Remove unnecessary whitespace

Reviewed-by: kvn, asmehra

.github/workflows/build-alpine-linux.yml

@@ -97,6 +97,7 @@ jobs:
           --with-zlib=system
           --with-jmod-compress=zip-1
           --with-external-symbols-in-bundles=none
+          --with-native-debug-symbols-level=1
           ${{ inputs.extra-conf-options }} ${{ inputs.configure-arguments }} || (
           echo "Dumping config.log:" &&
           cat config.log &&

.github/workflows/build-cross-compile.yml

@@ -180,6 +180,7 @@ jobs:
           --with-sysroot=sysroot
           --with-jmod-compress=zip-1
           --with-external-symbols-in-bundles=none
+          --with-native-debug-symbols-level=1
           CC=${{ matrix.gnu-arch }}-linux-gnu${{ matrix.gnu-abi}}-gcc-${{ inputs.gcc-major-version }}
           CXX=${{ matrix.gnu-arch }}-linux-gnu${{ matrix.gnu-abi}}-g++-${{ inputs.gcc-major-version }}
           ${{ inputs.extra-conf-options }} ${{ inputs.configure-arguments }} || (

.github/workflows/build-linux.yml

@@ -144,6 +144,7 @@ jobs:
           --with-zlib=system
           --with-jmod-compress=zip-1
           --with-external-symbols-in-bundles=none
+          --with-native-debug-symbols-level=1
           ${{ inputs.extra-conf-options }} ${{ inputs.configure-arguments }} || (
           echo "Dumping config.log:" &&
           cat config.log &&

.github/workflows/build-macos.yml

@@ -111,6 +111,7 @@ jobs:
           --with-zlib=system
           --with-jmod-compress=zip-1
           --with-external-symbols-in-bundles=none
+          --with-native-debug-symbols-level=1
           ${{ inputs.extra-conf-options }} ${{ inputs.configure-arguments }} || (
           echo "Dumping config.log:" &&
           cat config.log &&

doc/testing.html

@@ -72,6 +72,7 @@ id="toc-notes-for-specific-tests">Notes for Specific Tests</a>
 <li><a href="#non-us-locale" id="toc-non-us-locale">Non-US
 locale</a></li>
 <li><a href="#pkcs11-tests" id="toc-pkcs11-tests">PKCS11 Tests</a></li>
+<li><a href="#sctp-tests" id="toc-sctp-tests">SCTP Tests</a></li>
 <li><a href="#testing-ahead-of-time-optimizations"
 id="toc-testing-ahead-of-time-optimizations">Testing Ahead-of-time
 Optimizations</a></li>
@@ -621,6 +622,21 @@ element of the appropriate <code>@Artifact</code> class. (See
     JTREG=&quot;JAVA_OPTIONS=-Djdk.test.lib.artifacts.nsslib-linux_aarch64=/path/to/NSS-libs&quot;</code></pre>
 <p>For more notes about the PKCS11 tests, please refer to
 test/jdk/sun/security/pkcs11/README.</p>
+<h3 id="sctp-tests">SCTP Tests</h3>
+<p>The SCTP tests require the SCTP runtime library, which is often not
+installed by default in popular Linux distributions. Without this
+library, the SCTP tests will be skipped. If you want to enable the SCTP
+tests, you should install the SCTP library before running the tests.</p>
+<p>For distributions using the .deb packaging format and the apt tool
+(such as Debian, Ubuntu, etc.), try this:</p>
+<pre><code>sudo apt install libsctp1
+sudo modprobe sctp
+lsmod | grep sctp</code></pre>
+<p>For distributions using the .rpm packaging format and the dnf tool
+(such as Fedora, Red Hat, etc.), try this:</p>
+<pre><code>sudo dnf install -y lksctp-tools
+sudo modprobe sctp
+lsmod | grep sctp</code></pre>
 <h3 id="testing-ahead-of-time-optimizations">Testing Ahead-of-time
 Optimizations</h3>
 <p>One way to improve test coverage of ahead-of-time (AOT) optimizations

doc/testing.md

@@ -640,6 +640,32 @@ $ make test TEST="jtreg:sun/security/pkcs11/Secmod/AddTrustedCert.java" \
 For more notes about the PKCS11 tests, please refer to
 test/jdk/sun/security/pkcs11/README.
 
+
+### SCTP Tests
+
+The SCTP tests require the SCTP runtime library, which is often not installed
+by default in popular Linux distributions. Without this library, the SCTP tests
+will be skipped. If you want to enable the SCTP tests, you should install the
+SCTP library before running the tests.
+
+For distributions using the .deb packaging format and the apt tool
+(such as Debian, Ubuntu, etc.), try this:
+
+```
+sudo apt install libsctp1
+sudo modprobe sctp
+lsmod | grep sctp
+```
+
+For distributions using the .rpm packaging format and the dnf tool
+(such as Fedora, Red Hat, etc.), try this:
+
+```
+sudo dnf install -y lksctp-tools
+sudo modprobe sctp
+lsmod | grep sctp
+```
+
 ### Testing Ahead-of-time Optimizations
 
 One way to improve test coverage of ahead-of-time (AOT) optimizations in

make/autoconf/flags-cflags.m4

@@ -69,6 +69,19 @@ AC_DEFUN([FLAGS_SETUP_DEBUG_SYMBOLS],
   # Debug prefix mapping if supported by compiler
   DEBUG_PREFIX_CFLAGS=
 
+  UTIL_ARG_WITH(NAME: native-debug-symbols-level, TYPE: literal,
+    DEFAULT: [auto], VALID_VALUES: [auto 1 2 3],
+    CHECK_AVAILABLE: [
+      if test x$TOOLCHAIN_TYPE = xmicrosoft; then
+        AVAILABLE=false
+      fi
+    ],
+    DESC: [set the native debug symbol level (GCC and Clang only)],
+    DEFAULT_DESC: [toolchain default],
+    IF_AUTO: [
+      RESULT=""
+    ])
+
   # Debug symbols
   if test "x$TOOLCHAIN_TYPE" = xgcc; then
     if test "x$ALLOW_ABSOLUTE_PATHS_IN_OUTPUT" = "xfalse"; then
@@ -93,8 +106,9 @@ AC_DEFUN([FLAGS_SETUP_DEBUG_SYMBOLS],
       )
     fi
 
-    CFLAGS_DEBUG_SYMBOLS="-g -gdwarf-4"
-    ASFLAGS_DEBUG_SYMBOLS="-g"
+    # Debug info level should follow the debug format to be effective.
+    CFLAGS_DEBUG_SYMBOLS="-gdwarf-4 -g${NATIVE_DEBUG_SYMBOLS_LEVEL}"
+    ASFLAGS_DEBUG_SYMBOLS="-g${NATIVE_DEBUG_SYMBOLS_LEVEL}"
   elif test "x$TOOLCHAIN_TYPE" = xclang; then
     if test "x$ALLOW_ABSOLUTE_PATHS_IN_OUTPUT" = "xfalse"; then
       # Check if compiler supports -fdebug-prefix-map. If so, use that to make
@@ -113,8 +127,9 @@ AC_DEFUN([FLAGS_SETUP_DEBUG_SYMBOLS],
     FLAGS_COMPILER_CHECK_ARGUMENTS(ARGUMENT: [${GDWARF_FLAGS}],
         IF_FALSE: [GDWARF_FLAGS=""])
 
-    CFLAGS_DEBUG_SYMBOLS="-g ${GDWARF_FLAGS}"
-    ASFLAGS_DEBUG_SYMBOLS="-g"
+    # Debug info level should follow the debug format to be effective.
+    CFLAGS_DEBUG_SYMBOLS="${GDWARF_FLAGS} -g${NATIVE_DEBUG_SYMBOLS_LEVEL}"
+    ASFLAGS_DEBUG_SYMBOLS="-g${NATIVE_DEBUG_SYMBOLS_LEVEL}"
   elif test "x$TOOLCHAIN_TYPE" = xmicrosoft; then
     CFLAGS_DEBUG_SYMBOLS="-Z7"
   fi

make/common/Utils.gmk

@@ -114,7 +114,7 @@ EscapeDollar = $(subst $$,\$$,$(subst \$$,$$,$(strip $1)))
 
 ################################################################################
 # This macro works just like EscapeDollar above, but for #.
-EscapeHash = $(subst \#,\\\#,$(subst \\\#,\#,$(strip $1)))
+EscapeHash = $(subst $(HASH),\$(HASH),$(subst \$(HASH),$(HASH),$(strip $1)))
 
 ################################################################################
 # This macro translates $ into $$ to protect the string from make itself.

make/hotspot/lib/CompileGtest.gmk

@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2016, 2025, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2016, 2026, Oracle and/or its affiliates. All rights reserved.
 # DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 #
 # This code is free software; you can redistribute it and/or modify it
@@ -61,7 +61,8 @@ $(eval $(call SetupJdkLibrary, BUILD_GTEST_LIBGTEST, \
     INCLUDE_FILES := gtest-all.cc gmock-all.cc, \
     DISABLED_WARNINGS_gcc := format-nonliteral maybe-uninitialized undef \
         unused-result zero-as-null-pointer-constant, \
-    DISABLED_WARNINGS_clang := format-nonliteral undef unused-result, \
+    DISABLED_WARNINGS_clang := format-nonliteral undef unused-result \
+        zero-as-null-pointer-constant, \
     DISABLED_WARNINGS_microsoft := 4530, \
     DEFAULT_CFLAGS := false, \
     CFLAGS := $(JVM_CFLAGS) \

make/langtools/tools/propertiesparser/gen/ClassGenerator.java

@@ -286,7 +286,7 @@ public class ClassGenerator {
                         diagnosticFlags.isEmpty() ?
                           StubKind.DIAGNOSTIC_FLAGS_EMPTY.format() :
                           StubKind.DIAGNOSTIC_FLAGS_NON_EMPTY.format(diagnosticFlags),
-                        StubKind.LINT_CATEGORY.format("\"" + lintCategory + "\""),
+                        StubKind.LINT_CATEGORY.format(toLintFieldName(lintCategory)),
                         "\"" + keyParts[0] + "\"",
                         "\"" + Stream.of(keyParts).skip(2).collect(Collectors.joining(".")) + "\"",
                         javadoc);
@@ -314,7 +314,7 @@ public class ClassGenerator {
                             diagnosticFlags.isEmpty() ?
                               StubKind.DIAGNOSTIC_FLAGS_EMPTY.format() :
                               StubKind.DIAGNOSTIC_FLAGS_NON_EMPTY.format(diagnosticFlags),
-                            StubKind.LINT_CATEGORY.format("\"" + lintCategory + "\""),
+                            StubKind.LINT_CATEGORY.format(toLintFieldName(lintCategory)),
                             "\"" + keyParts[0] + "\"",
                             "\"" + Stream.of(keyParts).skip(2).collect(Collectors.joining(".")) + "\"",
                             argNames.stream().collect(Collectors.joining(", ")));
@@ -329,6 +329,11 @@ public class ClassGenerator {
         }
     }
 
+    String toLintFieldName(String lintCategory) {
+        return lintCategory.toUpperCase()
+                .replaceAll("-", "_");
+    }
+
     /**
      * Form the name of a factory method/field given a resource key.
      */

make/langtools/tools/propertiesparser/resources/templates.properties

@@ -87,7 +87,7 @@ suppress.warnings=\
   @SuppressWarnings("rawtypes")\n
 
 lint.category=\
-  LintCategory.get({0}).get()
+  LintCategory.{0}
 
 diagnostic.flags.empty=\
   EnumSet.noneOf(DiagnosticFlag.class)

make/modules/jdk.security.auth/Lib.gmk

@@ -31,13 +31,14 @@ include LibCommon.gmk
 ## Build libjaas
 ################################################################################
 
-$(eval $(call SetupJdkLibrary, BUILD_LIBJAAS, \
-    NAME := jaas, \
-    OPTIMIZATION := LOW, \
-    EXTRA_HEADER_DIRS := java.base:libjava, \
-    LIBS_windows := advapi32.lib mpr.lib netapi32.lib user32.lib, \
-))
-
-TARGETS += $(BUILD_LIBJAAS)
+ifeq ($(call isTargetOs, windows), true)
+  $(eval $(call SetupJdkLibrary, BUILD_LIBJAAS, \
+      NAME := jaas, \
+      OPTIMIZATION := LOW, \
+      EXTRA_HEADER_DIRS := java.base:libjava, \
+      LIBS_windows := advapi32.lib mpr.lib netapi32.lib user32.lib, \
+  ))
 
+  TARGETS += $(BUILD_LIBJAAS)
+endif
 ################################################################################

src/hotspot/cpu/aarch64/immediate_aarch64.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2023, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2023, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2014, 2020, Red Hat Inc. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -23,13 +23,13 @@
  *
  */
 
-#include <stdlib.h> // do not reorder
-#include <stdint.h> // do not reorder
-
+#include "cppstdlib/cstdlib.hpp"
 #include "immediate_aarch64.hpp"
 #include "metaprogramming/primitiveConversions.hpp"
 #include "utilities/globalDefinitions.hpp"
 
+#include <stdint.h>
+
 // there are at most 2^13 possible logical immediate encodings
 // however, some combinations of immr and imms are invalid
 static const unsigned  LI_TABLE_SIZE = (1 << 13);

src/hotspot/cpu/aarch64/immediate_aarch64.hpp

@@ -1,4 +1,5 @@
 /*
+ * Copyright (c) 2025, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2014, Red Hat Inc. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -22,10 +23,10 @@
  *
  */
 
-#ifndef _IMMEDIATE_H
-#define _IMMEDIATE_H
+#ifndef CPU_AARCH64_IMMEDIATE_AARCH64_HPP
+#define CPU_AARCH64_IMMEDIATE_AARCH64_HPP
 
-#include <sys/types.h>
+#include <stdint.h>
 
 /*
  * functions to map backwards and forwards between logical or floating
@@ -51,4 +52,4 @@ uint32_t encoding_for_logical_immediate(uint64_t immediate);
 uint64_t fp_immediate_for_encoding(uint32_t imm8, int is_dp);
 uint32_t encoding_for_fp_immediate(float immediate);
 
-#endif // _IMMEDIATE_H
+#endif // CPU_AARCH64_IMMEDIATE_AARCH64_HPP

src/hotspot/cpu/aarch64/macroAssembler_aarch64.cpp

@@ -5782,6 +5782,9 @@ address MacroAssembler::arrays_equals(Register a1, Register a2, Register tmp3,
     //      return false;
     bind(A_IS_NOT_NULL);
     ldrw(cnt1, Address(a1, length_offset));
+    ldrw(tmp5, Address(a2, length_offset));
+    cmp(cnt1, tmp5);
+    br(NE, DONE); // If lengths differ, return false
     // Increase loop counter by diff between base- and actual start-offset.
     addw(cnt1, cnt1, extra_length);
     lea(a1, Address(a1, start_offset));
@@ -5848,6 +5851,9 @@ address MacroAssembler::arrays_equals(Register a1, Register a2, Register tmp3,
     cbz(a1, DONE);
     ldrw(cnt1, Address(a1, length_offset));
     cbz(a2, DONE);
+    ldrw(tmp5, Address(a2, length_offset));
+    cmp(cnt1, tmp5);
+    br(NE, DONE); // If lengths differ, return false
     // Increase loop counter by diff between base- and actual start-offset.
     addw(cnt1, cnt1, extra_length);
 
@@ -6259,14 +6265,10 @@ void MacroAssembler::fill_words(Register base, Register cnt, Register value)
 
 // Intrinsic for
 //
-// - sun.nio.cs.ISO_8859_1.Encoder#encodeISOArray0(byte[] sa, int sp, byte[] da, int dp, int len)
-//   Encodes char[] to byte[] in ISO-8859-1
-//
-// - java.lang.StringCoding#encodeISOArray0(byte[] sa, int sp, byte[] da, int dp, int len)
-//   Encodes byte[] (containing UTF-16) to byte[] in ISO-8859-1
-//
-// - java.lang.StringCoding#encodeAsciiArray0(char[] sa, int sp, byte[] da, int dp, int len)
-//   Encodes char[] to byte[] in ASCII
+// - sun/nio/cs/ISO_8859_1$Encoder.implEncodeISOArray
+//     return the number of characters copied.
+// - java/lang/StringUTF16.compress
+//     return index of non-latin1 character if copy fails, otherwise 'len'.
 //
 // This version always returns the number of characters copied, and does not
 // clobber the 'len' register. A successful copy will complete with the post-

src/hotspot/cpu/aarch64/sharedRuntime_aarch64.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2014, 2021, Red Hat Inc. All rights reserved.
  * Copyright (c) 2021, Azul Systems, Inc. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
@@ -722,22 +722,20 @@ void SharedRuntime::generate_i2c2i_adapters(MacroAssembler *masm,
 
   // Class initialization barrier for static methods
   entry_address[AdapterBlob::C2I_No_Clinit_Check] = nullptr;
-  if (VM_Version::supports_fast_class_init_checks()) {
-    Label L_skip_barrier;
+  assert(VM_Version::supports_fast_class_init_checks(), "sanity");
+  Label L_skip_barrier;
 
-    { // Bypass the barrier for non-static methods
-      __ ldrh(rscratch1, Address(rmethod, Method::access_flags_offset()));
-      __ andsw(zr, rscratch1, JVM_ACC_STATIC);
-      __ br(Assembler::EQ, L_skip_barrier); // non-static
-    }
+  // Bypass the barrier for non-static methods
+  __ ldrh(rscratch1, Address(rmethod, Method::access_flags_offset()));
+  __ andsw(zr, rscratch1, JVM_ACC_STATIC);
+  __ br(Assembler::EQ, L_skip_barrier); // non-static
 
-    __ load_method_holder(rscratch2, rmethod);
-    __ clinit_barrier(rscratch2, rscratch1, &L_skip_barrier);
-    __ far_jump(RuntimeAddress(SharedRuntime::get_handle_wrong_method_stub()));
+  __ load_method_holder(rscratch2, rmethod);
+  __ clinit_barrier(rscratch2, rscratch1, &L_skip_barrier);
+  __ far_jump(RuntimeAddress(SharedRuntime::get_handle_wrong_method_stub()));
 
-    __ bind(L_skip_barrier);
-    entry_address[AdapterBlob::C2I_No_Clinit_Check] = __ pc();
-  }
+  __ bind(L_skip_barrier);
+  entry_address[AdapterBlob::C2I_No_Clinit_Check] = __ pc();
 
   BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
   bs->c2i_entry_barrier(masm);
@@ -1508,7 +1506,8 @@ nmethod* SharedRuntime::generate_native_wrapper(MacroAssembler* masm,
   // SVC, HVC, or SMC.  Make it a NOP.
   __ nop();
 
-  if (VM_Version::supports_fast_class_init_checks() && method->needs_clinit_barrier()) {
+  if (method->needs_clinit_barrier()) {
+    assert(VM_Version::supports_fast_class_init_checks(), "sanity");
     Label L_skip_barrier;
     __ mov_metadata(rscratch2, method->method_holder()); // InstanceKlass*
     __ clinit_barrier(rscratch2, rscratch1, &L_skip_barrier);

src/hotspot/cpu/aarch64/templateTable_aarch64.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2014, Red Hat Inc. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -2290,7 +2290,8 @@ void TemplateTable::resolve_cache_and_index_for_method(int byte_no,
   __ subs(zr, temp, (int) code);  // have we resolved this bytecode?
 
   // Class initialization barrier for static methods
-  if (VM_Version::supports_fast_class_init_checks() && bytecode() == Bytecodes::_invokestatic) {
+  if (bytecode() == Bytecodes::_invokestatic) {
+    assert(VM_Version::supports_fast_class_init_checks(), "sanity");
     __ br(Assembler::NE, L_clinit_barrier_slow);
     __ ldr(temp, Address(Rcache, in_bytes(ResolvedMethodEntry::method_offset())));
     __ load_method_holder(temp, temp);
@@ -2340,8 +2341,8 @@ void TemplateTable::resolve_cache_and_index_for_field(int byte_no,
   __ subs(zr, temp, (int) code);  // have we resolved this bytecode?
 
   // Class initialization barrier for static fields
-  if (VM_Version::supports_fast_class_init_checks() &&
-      (bytecode() == Bytecodes::_getstatic || bytecode() == Bytecodes::_putstatic)) {
+  if (bytecode() == Bytecodes::_getstatic || bytecode() == Bytecodes::_putstatic) {
+    assert(VM_Version::supports_fast_class_init_checks(), "sanity");
     const Register field_holder = temp;
 
     __ br(Assembler::NE, L_clinit_barrier_slow);

src/hotspot/cpu/arm/frame_arm.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2008, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2008, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -356,10 +356,10 @@ frame frame::sender_for_interpreter_frame(RegisterMap* map) const {
 bool frame::is_interpreted_frame_valid(JavaThread* thread) const {
   assert(is_interpreted_frame(), "Not an interpreted frame");
   // These are reasonable sanity checks
-  if (fp() == 0 || (intptr_t(fp()) & (wordSize-1)) != 0) {
+  if (fp() == nullptr || (intptr_t(fp()) & (wordSize-1)) != 0) {
     return false;
   }
-  if (sp() == 0 || (intptr_t(sp()) & (wordSize-1)) != 0) {
+  if (sp() == nullptr || (intptr_t(sp()) & (wordSize-1)) != 0) {
     return false;
   }
   if (fp() + interpreter_frame_initial_sp_offset < sp()) {

src/hotspot/cpu/arm/nativeInst_arm_32.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2008, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2008, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -172,7 +172,7 @@ void NativeMovConstReg::set_data(intptr_t x, address pc) {
 
     address addr = oop_addr != nullptr ? (address)oop_addr : (address)metadata_addr;
 
-    if(pc == 0) {
+    if (pc == nullptr) {
       offset = addr - instruction_address() - 8;
     } else {
       offset = addr - pc - 8;
@@ -228,7 +228,7 @@ void NativeMovConstReg::set_data(intptr_t x, address pc) {
 
 void NativeMovConstReg::set_pc_relative_offset(address addr, address pc) {
   int offset;
-  if (pc == 0) {
+  if (pc == nullptr) {
     offset = addr - instruction_address() - 8;
   } else {
     offset = addr - pc - 8;

src/hotspot/cpu/arm/nativeInst_arm_32.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2008, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2008, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -371,7 +371,7 @@ class NativeMovConstReg: public NativeInstruction {
  public:
 
   intptr_t data() const;
-  void set_data(intptr_t x, address pc = 0);
+  void set_data(intptr_t x, address pc = nullptr);
   bool is_pc_relative() {
     return !is_movw();
   }

src/hotspot/cpu/ppc/interp_masm_ppc_64.cpp

@@ -1109,11 +1109,11 @@ void InterpreterMacroAssembler::verify_method_data_pointer() {
   lhz(R11_scratch1, in_bytes(DataLayout::bci_offset()), R28_mdx);
   ld(R12_scratch2, in_bytes(Method::const_offset()), R19_method);
   addi(R11_scratch1, R11_scratch1, in_bytes(ConstMethod::codes_offset()));
-  add(R11_scratch1, R12_scratch2, R12_scratch2);
+  add(R11_scratch1, R11_scratch1, R12_scratch2);
   cmpd(CR0, R11_scratch1, R14_bcp);
   beq(CR0, verify_continue);
 
-  call_VM_leaf(CAST_FROM_FN_PTR(address, InterpreterRuntime::verify_mdp ), R19_method, R14_bcp, R28_mdx);
+  call_VM_leaf(CAST_FROM_FN_PTR(address, InterpreterRuntime::verify_mdp), R19_method, R14_bcp, R28_mdx);
 
   bind(verify_continue);
 #endif

src/hotspot/cpu/ppc/macroAssembler_ppc.cpp

@@ -4535,7 +4535,7 @@ void MacroAssembler::push_cont_fastpath() {
   Label done;
   ld_ptr(R0, JavaThread::cont_fastpath_offset(), R16_thread);
   cmpld(CR0, R1_SP, R0);
-  ble(CR0, done);
+  ble(CR0, done);          // if (SP <= _cont_fastpath) goto done;
   st_ptr(R1_SP, JavaThread::cont_fastpath_offset(), R16_thread);
   bind(done);
 }
@@ -4546,7 +4546,7 @@ void MacroAssembler::pop_cont_fastpath() {
   Label done;
   ld_ptr(R0, JavaThread::cont_fastpath_offset(), R16_thread);
   cmpld(CR0, R1_SP, R0);
-  ble(CR0, done);
+  blt(CR0, done);          // if (SP < _cont_fastpath) goto done;
   li(R0, 0);
   st_ptr(R0, JavaThread::cont_fastpath_offset(), R16_thread);
   bind(done);

src/hotspot/cpu/ppc/sharedRuntime_ppc.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2012, 2025 SAP SE. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -1237,26 +1237,24 @@ void SharedRuntime::generate_i2c2i_adapters(MacroAssembler *masm,
 
   // Class initialization barrier for static methods
   entry_address[AdapterBlob::C2I_No_Clinit_Check] = nullptr;
-  if (VM_Version::supports_fast_class_init_checks()) {
-    Label L_skip_barrier;
+  assert(VM_Version::supports_fast_class_init_checks(), "sanity");
+  Label L_skip_barrier;
 
-    { // Bypass the barrier for non-static methods
-      __ lhz(R0, in_bytes(Method::access_flags_offset()), R19_method);
-      __ andi_(R0, R0, JVM_ACC_STATIC);
-      __ beq(CR0, L_skip_barrier); // non-static
-    }
+  // Bypass the barrier for non-static methods
+  __ lhz(R0, in_bytes(Method::access_flags_offset()), R19_method);
+  __ andi_(R0, R0, JVM_ACC_STATIC);
+  __ beq(CR0, L_skip_barrier); // non-static
 
-    Register klass = R11_scratch1;
-    __ load_method_holder(klass, R19_method);
-    __ clinit_barrier(klass, R16_thread, &L_skip_barrier /*L_fast_path*/);
+  Register klass = R11_scratch1;
+  __ load_method_holder(klass, R19_method);
+  __ clinit_barrier(klass, R16_thread, &L_skip_barrier /*L_fast_path*/);
 
-    __ load_const_optimized(klass, SharedRuntime::get_handle_wrong_method_stub(), R0);
-    __ mtctr(klass);
-    __ bctr();
+  __ load_const_optimized(klass, SharedRuntime::get_handle_wrong_method_stub(), R0);
+  __ mtctr(klass);
+  __ bctr();
 
-    __ bind(L_skip_barrier);
-    entry_address[AdapterBlob::C2I_No_Clinit_Check] = __ pc();
-  }
+  __ bind(L_skip_barrier);
+  entry_address[AdapterBlob::C2I_No_Clinit_Check] = __ pc();
 
   BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
   bs->c2i_entry_barrier(masm, /* tmp register*/ ic_klass, /* tmp register*/ receiver_klass, /* tmp register*/ code);
@@ -2210,7 +2208,8 @@ nmethod *SharedRuntime::generate_native_wrapper(MacroAssembler *masm,
   // --------------------------------------------------------------------------
   vep_start_pc = (intptr_t)__ pc();
 
-  if (VM_Version::supports_fast_class_init_checks() && method->needs_clinit_barrier()) {
+  if (method->needs_clinit_barrier()) {
+    assert(VM_Version::supports_fast_class_init_checks(), "sanity");
     Label L_skip_barrier;
     Register klass = r_temp_1;
     // Notify OOP recorder (don't need the relocation)

src/hotspot/cpu/ppc/templateTable_ppc_64.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2014, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2013, 2025 SAP SE. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -2199,7 +2199,8 @@ void TemplateTable::resolve_cache_and_index_for_method(int byte_no, Register Rca
   __ isync(); // Order load wrt. succeeding loads.
 
   // Class initialization barrier for static methods
-  if (VM_Version::supports_fast_class_init_checks() && bytecode() == Bytecodes::_invokestatic) {
+  if (bytecode() == Bytecodes::_invokestatic) {
+    assert(VM_Version::supports_fast_class_init_checks(), "sanity");
     const Register method = Rscratch;
     const Register klass  = Rscratch;
 
@@ -2244,8 +2245,8 @@ void TemplateTable::resolve_cache_and_index_for_field(int byte_no, Register Rcac
   __ isync(); // Order load wrt. succeeding loads.
 
   // Class initialization barrier for static fields
-  if (VM_Version::supports_fast_class_init_checks() &&
-      (bytecode() == Bytecodes::_getstatic || bytecode() == Bytecodes::_putstatic)) {
+  if (bytecode() == Bytecodes::_getstatic || bytecode() == Bytecodes::_putstatic) {
+    assert(VM_Version::supports_fast_class_init_checks(), "sanity");
     const Register field_holder = R4_ARG2;
 
     // InterpreterRuntime::resolve_get_put sets field_holder and finally release-stores put_code.

src/hotspot/cpu/riscv/c2_MacroAssembler_riscv.cpp

@@ -2813,14 +2813,10 @@ void C2_MacroAssembler::char_array_compress_v(Register src, Register dst, Regist
 
 // Intrinsic for
 //
-// - sun.nio.cs.ISO_8859_1.Encoder#encodeISOArray0(byte[] sa, int sp, byte[] da, int dp, int len)
-//   Encodes char[] to byte[] in ISO-8859-1
-//
-// - java.lang.StringCoding#encodeISOArray0(byte[] sa, int sp, byte[] da, int dp, int len)
-//   Encodes byte[] (containing UTF-16) to byte[] in ISO-8859-1
-//
-// - java.lang.StringCoding#encodeAsciiArray0(char[] sa, int sp, byte[] da, int dp, int len)
-//   Encodes char[] to byte[] in ASCII
+// - sun/nio/cs/ISO_8859_1$Encoder.implEncodeISOArray
+//     return the number of characters copied.
+// - java/lang/StringUTF16.compress
+//     return index of non-latin1 character if copy fails, otherwise 'len'.
 //
 // This version always returns the number of characters copied. A successful
 // copy will complete with the post-condition: 'res' == 'len', while an

src/hotspot/cpu/riscv/sharedRuntime_riscv.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2014, 2020, Red Hat Inc. All rights reserved.
  * Copyright (c) 2020, 2023, Huawei Technologies Co., Ltd. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
@@ -213,7 +213,7 @@ void RegisterSaver::restore_live_registers(MacroAssembler* masm) {
 // Is vector's size (in bytes) bigger than a size saved by default?
 // riscv does not ovlerlay the floating-point registers on vector registers like aarch64.
 bool SharedRuntime::is_wide_vector(int size) {
-  return UseRVV;
+  return UseRVV && size > 0;
 }
 
 // ---------------------------------------------------------------------------
@@ -637,22 +637,20 @@ void SharedRuntime::generate_i2c2i_adapters(MacroAssembler *masm,
 
   // Class initialization barrier for static methods
   entry_address[AdapterBlob::C2I_No_Clinit_Check] = nullptr;
-  if (VM_Version::supports_fast_class_init_checks()) {
-    Label L_skip_barrier;
+  assert(VM_Version::supports_fast_class_init_checks(), "sanity");
+  Label L_skip_barrier;
 
-    { // Bypass the barrier for non-static methods
-      __ load_unsigned_short(t0, Address(xmethod, Method::access_flags_offset()));
-      __ test_bit(t1, t0, exact_log2(JVM_ACC_STATIC));
-      __ beqz(t1, L_skip_barrier); // non-static
-    }
+  // Bypass the barrier for non-static methods
+  __ load_unsigned_short(t0, Address(xmethod, Method::access_flags_offset()));
+  __ test_bit(t1, t0, exact_log2(JVM_ACC_STATIC));
+  __ beqz(t1, L_skip_barrier); // non-static
 
-    __ load_method_holder(t1, xmethod);
-    __ clinit_barrier(t1, t0, &L_skip_barrier);
-    __ far_jump(RuntimeAddress(SharedRuntime::get_handle_wrong_method_stub()));
+  __ load_method_holder(t1, xmethod);
+  __ clinit_barrier(t1, t0, &L_skip_barrier);
+  __ far_jump(RuntimeAddress(SharedRuntime::get_handle_wrong_method_stub()));
 
-    __ bind(L_skip_barrier);
-    entry_address[AdapterBlob::C2I_No_Clinit_Check] = __ pc();
-  }
+  __ bind(L_skip_barrier);
+  entry_address[AdapterBlob::C2I_No_Clinit_Check] = __ pc();
 
   BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
   bs->c2i_entry_barrier(masm);
@@ -1443,7 +1441,8 @@ nmethod* SharedRuntime::generate_native_wrapper(MacroAssembler* masm,
     __ nop();  // 4 bytes
   }
 
-  if (VM_Version::supports_fast_class_init_checks() && method->needs_clinit_barrier()) {
+  if (method->needs_clinit_barrier()) {
+    assert(VM_Version::supports_fast_class_init_checks(), "sanity");
     Label L_skip_barrier;
     __ mov_metadata(t1, method->method_holder()); // InstanceKlass*
     __ clinit_barrier(t1, t0, &L_skip_barrier);

src/hotspot/cpu/riscv/templateTable_riscv.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2014, Red Hat Inc. All rights reserved.
  * Copyright (c) 2020, 2023, Huawei Technologies Co., Ltd. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
@@ -2192,7 +2192,8 @@ void TemplateTable::resolve_cache_and_index_for_method(int byte_no,
   __ mv(t0, (int) code);
 
   // Class initialization barrier for static methods
-  if (VM_Version::supports_fast_class_init_checks() && bytecode() == Bytecodes::_invokestatic) {
+  if (bytecode() == Bytecodes::_invokestatic) {
+    assert(VM_Version::supports_fast_class_init_checks(), "sanity");
     __ bne(temp, t0, L_clinit_barrier_slow);  // have we resolved this bytecode?
     __ ld(temp, Address(Rcache, in_bytes(ResolvedMethodEntry::method_offset())));
     __ load_method_holder(temp, temp);
@@ -2243,8 +2244,8 @@ void TemplateTable::resolve_cache_and_index_for_field(int byte_no,
   __ mv(t0, (int) code);  // have we resolved this bytecode?
 
   // Class initialization barrier for static fields
-  if (VM_Version::supports_fast_class_init_checks() &&
-      (bytecode() == Bytecodes::_getstatic || bytecode() == Bytecodes::_putstatic)) {
+  if (bytecode() == Bytecodes::_getstatic || bytecode() == Bytecodes::_putstatic) {
+    assert(VM_Version::supports_fast_class_init_checks(), "sanity");
     const Register field_holder = temp;
 
     __ bne(temp, t0, L_clinit_barrier_slow);

src/hotspot/cpu/riscv/vm_version_riscv.cpp

@@ -167,11 +167,6 @@ void VM_Version::common_initialize() {
       (unaligned_scalar.value() == MISALIGNED_SCALAR_FAST));
   }
 
-  if (FLAG_IS_DEFAULT(AlignVector)) {
-    FLAG_SET_DEFAULT(AlignVector,
-      unaligned_vector.value() != MISALIGNED_VECTOR_FAST);
-  }
-
 #ifdef __riscv_ztso
   // Hotspot is compiled with TSO support, it will only run on hardware which
   // supports Ztso
@@ -242,6 +237,11 @@ void VM_Version::c2_initialize() {
     }
   }
 
+  if (FLAG_IS_DEFAULT(AlignVector)) {
+    FLAG_SET_DEFAULT(AlignVector,
+      unaligned_vector.value() != MISALIGNED_VECTOR_FAST);
+  }
+
   // NOTE: Make sure codes dependent on UseRVV are put after MaxVectorSize initialize,
   //       as there are extra checks inside it which could disable UseRVV
   //       in some situations.

src/hotspot/cpu/s390/sharedRuntime_s390.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2016, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2016, 2024 SAP SE. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -1567,7 +1567,8 @@ nmethod *SharedRuntime::generate_native_wrapper(MacroAssembler *masm,
   //---------------------------------------------------------------------
   wrapper_VEPStart = __ offset();
 
-  if (VM_Version::supports_fast_class_init_checks() && method->needs_clinit_barrier()) {
+  if (method->needs_clinit_barrier()) {
+    assert(VM_Version::supports_fast_class_init_checks(), "sanity");
     Label L_skip_barrier;
     Register klass = Z_R1_scratch;
     // Notify OOP recorder (don't need the relocation)
@@ -2378,24 +2379,22 @@ void SharedRuntime::generate_i2c2i_adapters(MacroAssembler *masm,
 
   // Class initialization barrier for static methods
   entry_address[AdapterBlob::C2I_No_Clinit_Check] = nullptr;
-  if (VM_Version::supports_fast_class_init_checks()) {
-    Label L_skip_barrier;
+  assert(VM_Version::supports_fast_class_init_checks(), "sanity");
+  Label L_skip_barrier;
 
-    { // Bypass the barrier for non-static methods
-      __ testbit_ushort(Address(Z_method, Method::access_flags_offset()), JVM_ACC_STATIC_BIT);
-      __ z_bfalse(L_skip_barrier); // non-static
-    }
+  // Bypass the barrier for non-static methods
+  __ testbit_ushort(Address(Z_method, Method::access_flags_offset()), JVM_ACC_STATIC_BIT);
+  __ z_bfalse(L_skip_barrier); // non-static
 
-    Register klass = Z_R11;
-    __ load_method_holder(klass, Z_method);
-    __ clinit_barrier(klass, Z_thread, &L_skip_barrier /*L_fast_path*/);
+  Register klass = Z_R11;
+  __ load_method_holder(klass, Z_method);
+  __ clinit_barrier(klass, Z_thread, &L_skip_barrier /*L_fast_path*/);
 
-    __ load_const_optimized(klass, SharedRuntime::get_handle_wrong_method_stub());
-    __ z_br(klass);
+  __ load_const_optimized(klass, SharedRuntime::get_handle_wrong_method_stub());
+  __ z_br(klass);
 
-    __ bind(L_skip_barrier);
-    entry_address[AdapterBlob::C2I_No_Clinit_Check] = __ pc();
-  }
+  __ bind(L_skip_barrier);
+  entry_address[AdapterBlob::C2I_No_Clinit_Check] = __ pc();
 
   gen_c2i_adapter(masm, total_args_passed, comp_args_on_stack, sig_bt, regs, skip_fixup);
   return;

src/hotspot/cpu/s390/templateTable_s390.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2016, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2016, 2024 SAP SE. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -2377,7 +2377,8 @@ void TemplateTable::resolve_cache_and_index_for_method(int byte_no,
   __ z_cli(Address(Rcache, bc_offset), code);
 
   // Class initialization barrier for static methods
-  if (VM_Version::supports_fast_class_init_checks() && bytecode() == Bytecodes::_invokestatic) {
+  if (bytecode() == Bytecodes::_invokestatic) {
+    assert(VM_Version::supports_fast_class_init_checks(), "sanity");
     const Register method = Z_R1_scratch;
     const Register klass  = Z_R1_scratch;
     __ z_brne(L_clinit_barrier_slow);
@@ -2427,8 +2428,8 @@ void TemplateTable::resolve_cache_and_index_for_field(int byte_no,
   __ z_cli(Address(cache, code_offset), code);
 
   // Class initialization barrier for static fields
-  if (VM_Version::supports_fast_class_init_checks() &&
-      (bytecode() == Bytecodes::_getstatic || bytecode() == Bytecodes::_putstatic)) {
+  if (bytecode() == Bytecodes::_getstatic || bytecode() == Bytecodes::_putstatic) {
+    assert(VM_Version::supports_fast_class_init_checks(), "sanity");
     const Register field_holder = index;
 
     __ z_brne(L_clinit_barrier_slow);

src/hotspot/cpu/x86/c2_stubGenerator_x86_64_string.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2024, 2025, Intel Corporation. All rights reserved.
+ * Copyright (c) 2024, 2026, Intel Corporation. All rights reserved.
  *
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -1330,10 +1330,12 @@ static void big_case_loop_helper(bool sizeKnown, int size, Label &noMatch, Label
   // Clarification:  The BYTE_K compare above compares haystack[(n-32):(n-1)].  We need to
   // compare haystack[(k-1):(k-1+31)].  Subtracting either index gives shift value of
   // (k + 31 - n):  x = (k-1+31)-(n-1) = k-1+31-n+1 = k+31-n.
+  // When isU is set, similarly, shift is from haystack[(n-32):(n-1)] to [(k-2):(k-2+31)]
+
   if (sizeKnown) {
-    __ movl(temp2, 31 + size);
+    __ movl(temp2, (isU ? 30 : 31) + size);
   } else {
-    __ movl(temp2, 31);
+    __ movl(temp2, isU ? 30 : 31);
     __ addl(temp2, needleLen);
   }
   __ subl(temp2, hsLength);

src/hotspot/cpu/x86/macroAssembler_x86.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -6086,7 +6086,7 @@ void MacroAssembler::generate_fill(BasicType t, bool aligned,
           vpbroadcastd(xtmp, xtmp, Assembler::AVX_512bit);
 
           subptr(count, 16 << shift);
-          jccb(Assembler::less, L_check_fill_32_bytes);
+          jcc(Assembler::less, L_check_fill_32_bytes);
           align(16);
 
           BIND(L_fill_64_bytes_loop_avx3);
@@ -6251,46 +6251,32 @@ void MacroAssembler::evpbroadcast(BasicType type, XMMRegister dst, Register src,
   }
 }
 
-// Encode given char[]/byte[] to byte[] in ISO_8859_1 or ASCII
-//
-// @IntrinsicCandidate
-// int sun.nio.cs.ISO_8859_1.Encoder#encodeISOArray0(
-//         char[] sa, int sp, byte[] da, int dp, int len) {
-//     int i = 0;
-//     for (; i < len; i++) {
-//         char c = sa[sp++];
-//         if (c > '\u00FF')
-//             break;
-//         da[dp++] = (byte) c;
-//     }
-//     return i;
-// }
-//
-// @IntrinsicCandidate
-// int java.lang.StringCoding.encodeISOArray0(
-//         byte[] sa, int sp, byte[] da, int dp, int len) {
-//   int i = 0;
-//   for (; i < len; i++) {
-//     char c = StringUTF16.getChar(sa, sp++);
-//     if (c > '\u00FF')
-//       break;
-//     da[dp++] = (byte) c;
-//   }
-//   return i;
-// }
-//
-// @IntrinsicCandidate
-// int java.lang.StringCoding.encodeAsciiArray0(
-//         char[] sa, int sp, byte[] da, int dp, int len) {
-//   int i = 0;
-//   for (; i < len; i++) {
-//     char c = sa[sp++];
-//     if (c >= '\u0080')
-//       break;
-//     da[dp++] = (byte) c;
-//   }
-//   return i;
-// }
+// encode char[] to byte[] in ISO_8859_1 or ASCII
+   //@IntrinsicCandidate
+   //private static int implEncodeISOArray(byte[] sa, int sp,
+   //byte[] da, int dp, int len) {
+   //  int i = 0;
+   //  for (; i < len; i++) {
+   //    char c = StringUTF16.getChar(sa, sp++);
+   //    if (c > '\u00FF')
+   //      break;
+   //    da[dp++] = (byte)c;
+   //  }
+   //  return i;
+   //}
+   //
+   //@IntrinsicCandidate
+   //private static int implEncodeAsciiArray(char[] sa, int sp,
+   //    byte[] da, int dp, int len) {
+   //  int i = 0;
+   //  for (; i < len; i++) {
+   //    char c = sa[sp++];
+   //    if (c >= '\u0080')
+   //      break;
+   //    da[dp++] = (byte)c;
+   //  }
+   //  return i;
+   //}
 void MacroAssembler::encode_iso_array(Register src, Register dst, Register len,
   XMMRegister tmp1Reg, XMMRegister tmp2Reg,
   XMMRegister tmp3Reg, XMMRegister tmp4Reg,

src/hotspot/cpu/x86/register_x86.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2000, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -32,14 +32,10 @@ const KRegister::KRegisterImpl         all_KRegisterImpls    [KRegister::number_
 
 const char * Register::RegisterImpl::name() const {
   static const char *const names[number_of_registers] = {
-#ifdef _LP64
     "rax", "rcx", "rdx", "rbx", "rsp", "rbp", "rsi", "rdi",
     "r8",  "r9",  "r10", "r11", "r12", "r13", "r14", "r15",
     "r16", "r17", "r18", "r19", "r20", "r21", "r22", "r23",
     "r24", "r25", "r26", "r27", "r28", "r29", "r30", "r31"
-#else
-    "eax", "ecx", "edx", "ebx", "esp", "ebp", "esi", "edi"
-#endif // _LP64
   };
   return is_valid() ? names[encoding()] : "noreg";
 }
@@ -54,11 +50,9 @@ const char* FloatRegister::FloatRegisterImpl::name() const {
 const char* XMMRegister::XMMRegisterImpl::name() const {
   static const char *const names[number_of_registers] = {
     "xmm0",    "xmm1",  "xmm2",  "xmm3",  "xmm4",  "xmm5",  "xmm6",  "xmm7"
-#ifdef _LP64
     ,"xmm8",   "xmm9",  "xmm10", "xmm11", "xmm12", "xmm13", "xmm14", "xmm15"
     ,"xmm16",  "xmm17", "xmm18", "xmm19", "xmm20", "xmm21", "xmm22", "xmm23"
     ,"xmm24",  "xmm25", "xmm26", "xmm27", "xmm28", "xmm29", "xmm30", "xmm31"
-#endif // _LP64
   };
   return is_valid() ? names[encoding()] : "xnoreg";
 }

src/hotspot/cpu/x86/register_x86.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000, 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2000, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -34,7 +34,7 @@
 class VMRegImpl;
 typedef VMRegImpl* VMReg;
 
-// The implementation of integer registers for the x86/x64 architectures.
+// The implementation of integer registers for the x64 architectures.
 class Register {
 private:
   int _encoding;
@@ -44,11 +44,9 @@ private:
 public:
   inline friend constexpr Register as_Register(int encoding);
 
-  enum {
-    number_of_registers      = LP64_ONLY( 32 ) NOT_LP64( 8 ),
-    number_of_byte_registers = LP64_ONLY( 32 ) NOT_LP64( 4 ),
-    max_slots_per_register   = LP64_ONLY(  2 ) NOT_LP64( 1 )
-  };
+  static const int number_of_registers      = 32;
+  static const int number_of_byte_registers = 32;
+  static const int max_slots_per_register   =  2;
 
   class RegisterImpl: public AbstractRegisterImpl {
     friend class Register;
@@ -79,11 +77,9 @@ public:
 
   // Actually available GP registers for use, depending on actual CPU capabilities and flags.
   static int available_gp_registers() {
-#ifdef _LP64
     if (!UseAPX) {
       return number_of_registers / 2;
     }
-#endif // _LP64
     return number_of_registers;
   }
 };
@@ -116,9 +112,8 @@ constexpr Register rsp = as_Register(4);
 constexpr Register rbp = as_Register(5);
 constexpr Register rsi = as_Register(6);
 constexpr Register rdi = as_Register(7);
-#ifdef _LP64
-constexpr Register r8  = as_Register( 8);
-constexpr Register r9  = as_Register( 9);
+constexpr Register r8  = as_Register(8);
+constexpr Register r9  = as_Register(9);
 constexpr Register r10 = as_Register(10);
 constexpr Register r11 = as_Register(11);
 constexpr Register r12 = as_Register(12);
@@ -141,7 +136,6 @@ constexpr Register r28 = as_Register(28);
 constexpr Register r29 = as_Register(29);
 constexpr Register r30 = as_Register(30);
 constexpr Register r31 = as_Register(31);
-#endif // _LP64
 
 
 // The implementation of x87 floating point registers for the ia32 architecture.
@@ -154,10 +148,8 @@ private:
 public:
   inline friend constexpr FloatRegister as_FloatRegister(int encoding);
 
-  enum {
-    number_of_registers    = 8,
-    max_slots_per_register = 2
-  };
+  static const int number_of_registers    = 8;
+  static const int max_slots_per_register = 2;
 
   class FloatRegisterImpl: public AbstractRegisterImpl {
     friend class FloatRegister;
@@ -217,10 +209,8 @@ private:
 public:
   inline friend constexpr XMMRegister as_XMMRegister(int encoding);
 
-  enum {
-    number_of_registers    = LP64_ONLY( 32 ) NOT_LP64(  8 ),
-    max_slots_per_register = LP64_ONLY( 16 ) NOT_LP64( 16 )   // 512-bit
-  };
+  static const int number_of_registers    =  32;
+  static const int max_slots_per_register =  16; // 512-bit
 
   class XMMRegisterImpl: public AbstractRegisterImpl {
     friend class XMMRegister;
@@ -250,11 +240,9 @@ public:
 
   // Actually available XMM registers for use, depending on actual CPU capabilities and flags.
   static int available_xmm_registers() {
-#ifdef _LP64
     if (UseAVX < 3) {
       return number_of_registers / 2;
     }
-#endif // _LP64
     return number_of_registers;
   }
 };
@@ -287,7 +275,6 @@ constexpr XMMRegister xmm4  = as_XMMRegister( 4);
 constexpr XMMRegister xmm5  = as_XMMRegister( 5);
 constexpr XMMRegister xmm6  = as_XMMRegister( 6);
 constexpr XMMRegister xmm7  = as_XMMRegister( 7);
-#ifdef _LP64
 constexpr XMMRegister xmm8  = as_XMMRegister( 8);
 constexpr XMMRegister xmm9  = as_XMMRegister( 9);
 constexpr XMMRegister xmm10 = as_XMMRegister(10);
@@ -312,7 +299,6 @@ constexpr XMMRegister xmm28 = as_XMMRegister(28);
 constexpr XMMRegister xmm29 = as_XMMRegister(29);
 constexpr XMMRegister xmm30 = as_XMMRegister(30);
 constexpr XMMRegister xmm31 = as_XMMRegister(31);
-#endif // _LP64
 
 
 // The implementation of AVX-512 opmask registers.
@@ -394,25 +380,17 @@ constexpr KRegister k7 = as_KRegister(7);
 // Define a class that exports it.
 class ConcreteRegisterImpl : public AbstractRegisterImpl {
  public:
-  enum {
-    max_gpr = Register::number_of_registers * Register::max_slots_per_register,
-    max_fpr = max_gpr + FloatRegister::number_of_registers * FloatRegister::max_slots_per_register,
-    max_xmm = max_fpr + XMMRegister::number_of_registers * XMMRegister::max_slots_per_register,
-    max_kpr = max_xmm + KRegister::number_of_registers * KRegister::max_slots_per_register,
+    static const int max_gpr = Register::number_of_registers * Register::max_slots_per_register;
+    static const int max_fpr = max_gpr + FloatRegister::number_of_registers * FloatRegister::max_slots_per_register;
+    static const int max_xmm = max_fpr + XMMRegister::number_of_registers * XMMRegister::max_slots_per_register;
+    static const int max_kpr = max_xmm + KRegister::number_of_registers * KRegister::max_slots_per_register;
 
     // A big enough number for C2: all the registers plus flags
     // This number must be large enough to cover REG_COUNT (defined by c2) registers.
     // There is no requirement that any ordering here matches any ordering c2 gives
     // it's optoregs.
-
-    // x86_32.ad defines additional dummy FILL0-FILL7 registers, in order to tally
-    // REG_COUNT (computed by ADLC based on the number of reg_defs seen in .ad files)
-    // with ConcreteRegisterImpl::number_of_registers additional count of 8 is being
-    // added for 32 bit jvm.
-    number_of_registers = max_kpr +       // gpr/fpr/xmm/kpr
-                          NOT_LP64( 8 + ) // FILL0-FILL7 in x86_32.ad
-                          1               // eflags
-  };
+    static const int number_of_registers = max_kpr + // gpr/fpr/xmm/kpr
+                                           1;        // eflags
 };
 
 template <>

src/hotspot/cpu/x86/sharedRuntime_x86_64.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -1043,26 +1043,24 @@ void SharedRuntime::generate_i2c2i_adapters(MacroAssembler *masm,
 
   // Class initialization barrier for static methods
   entry_address[AdapterBlob::C2I_No_Clinit_Check] = nullptr;
-  if (VM_Version::supports_fast_class_init_checks()) {
-    Label L_skip_barrier;
-    Register method = rbx;
+  assert(VM_Version::supports_fast_class_init_checks(), "sanity");
+  Label L_skip_barrier;
+  Register method = rbx;
 
-    { // Bypass the barrier for non-static methods
-      Register flags = rscratch1;
-      __ load_unsigned_short(flags, Address(method, Method::access_flags_offset()));
-      __ testl(flags, JVM_ACC_STATIC);
-      __ jcc(Assembler::zero, L_skip_barrier); // non-static
-    }
+  // Bypass the barrier for non-static methods
+  Register flags = rscratch1;
+  __ load_unsigned_short(flags, Address(method, Method::access_flags_offset()));
+  __ testl(flags, JVM_ACC_STATIC);
+  __ jcc(Assembler::zero, L_skip_barrier); // non-static
 
-    Register klass = rscratch1;
-    __ load_method_holder(klass, method);
-    __ clinit_barrier(klass, &L_skip_barrier /*L_fast_path*/);
+  Register klass = rscratch1;
+  __ load_method_holder(klass, method);
+  __ clinit_barrier(klass, &L_skip_barrier /*L_fast_path*/);
 
-    __ jump(RuntimeAddress(SharedRuntime::get_handle_wrong_method_stub())); // slow path
+  __ jump(RuntimeAddress(SharedRuntime::get_handle_wrong_method_stub())); // slow path
 
-    __ bind(L_skip_barrier);
-    entry_address[AdapterBlob::C2I_No_Clinit_Check] = __ pc();
-  }
+  __ bind(L_skip_barrier);
+  entry_address[AdapterBlob::C2I_No_Clinit_Check] = __ pc();
 
   BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
   bs->c2i_entry_barrier(masm);
@@ -1904,7 +1902,8 @@ nmethod* SharedRuntime::generate_native_wrapper(MacroAssembler* masm,
 
   int vep_offset = ((intptr_t)__ pc()) - start;
 
-  if (VM_Version::supports_fast_class_init_checks() && method->needs_clinit_barrier()) {
+  if (method->needs_clinit_barrier()) {
+    assert(VM_Version::supports_fast_class_init_checks(), "sanity");
     Label L_skip_barrier;
     Register klass = r10;
     __ mov_metadata(klass, method->method_holder()); // InstanceKlass*
@@ -3602,4 +3601,3 @@ RuntimeStub* SharedRuntime::generate_jfr_return_lease() {
 }
 
 #endif // INCLUDE_JFR
-

src/hotspot/cpu/x86/stubGenerator_x86_64_kyber.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2025, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -64,6 +64,39 @@ static address kyberAvx512ConstsAddr(int offset) {
 
 const Register scratch = r10;
 
+ATTRIBUTE_ALIGNED(64) static const uint8_t kyberAvx512_12To16Dup[] = {
+// 0 - 63
+    0, 1, 1, 2, 3, 4, 4, 5, 6, 7, 7, 8, 9, 10, 10, 11, 12, 13, 13, 14, 15, 16,
+    16, 17, 18, 19, 19, 20, 21, 22, 22, 23, 24, 25, 25, 26, 27, 28, 28, 29, 30,
+    31, 31, 32, 33, 34, 34, 35, 36, 37, 37, 38, 39, 40, 40, 41, 42, 43, 43, 44,
+    45, 46, 46, 47
+  };
+
+static address kyberAvx512_12To16DupAddr() {
+  return (address) kyberAvx512_12To16Dup;
+}
+
+ATTRIBUTE_ALIGNED(64) static const uint16_t kyberAvx512_12To16Shift[] = {
+// 0 - 31
+    0, 4, 0, 4, 0, 4, 0, 4, 0, 4, 0, 4, 0, 4, 0, 4, 0, 4, 0, 4, 0, 4, 0, 4, 0,
+    4, 0, 4, 0, 4, 0, 4
+  };
+
+static address kyberAvx512_12To16ShiftAddr() {
+  return (address) kyberAvx512_12To16Shift;
+}
+
+ATTRIBUTE_ALIGNED(64) static const uint64_t kyberAvx512_12To16And[] = {
+// 0 - 7
+    0x0FFF0FFF0FFF0FFF, 0x0FFF0FFF0FFF0FFF, 0x0FFF0FFF0FFF0FFF,
+    0x0FFF0FFF0FFF0FFF, 0x0FFF0FFF0FFF0FFF, 0x0FFF0FFF0FFF0FFF,
+    0x0FFF0FFF0FFF0FFF, 0x0FFF0FFF0FFF0FFF
+  };
+
+static address kyberAvx512_12To16AndAddr() {
+  return (address) kyberAvx512_12To16And;
+}
+
 ATTRIBUTE_ALIGNED(64) static const uint16_t kyberAvx512NttPerms[] = {
 // 0
     0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
@@ -822,10 +855,65 @@ address generate_kyber12To16_avx512(StubGenerator *stubgen,
 
   const Register perms = r11;
 
-  Label Loop;
+  Label Loop, VBMILoop;
 
   __ addptr(condensed, condensedOffs);
 
+  if (VM_Version::supports_avx512_vbmi()) {
+    // mask load for the first 48 bytes of each vector
+    __ mov64(rax, 0x0000FFFFFFFFFFFF);
+    __ kmovql(k1, rax);
+
+    __ lea(perms, ExternalAddress(kyberAvx512_12To16DupAddr()));
+    __ evmovdqub(xmm20, Address(perms), Assembler::AVX_512bit);
+
+    __ lea(perms, ExternalAddress(kyberAvx512_12To16ShiftAddr()));
+    __ evmovdquw(xmm21, Address(perms), Assembler::AVX_512bit);
+
+    __ lea(perms, ExternalAddress(kyberAvx512_12To16AndAddr()));
+    __ evmovdquq(xmm22, Address(perms), Assembler::AVX_512bit);
+
+    __ align(OptoLoopAlignment);
+    __ BIND(VBMILoop);
+
+      __ evmovdqub(xmm0, k1, Address(condensed, 0), false,
+                   Assembler::AVX_512bit);
+      __ evmovdqub(xmm1, k1, Address(condensed, 48), false,
+                   Assembler::AVX_512bit);
+      __ evmovdqub(xmm2, k1, Address(condensed, 96), false,
+                   Assembler::AVX_512bit);
+      __ evmovdqub(xmm3, k1, Address(condensed, 144), false,
+                   Assembler::AVX_512bit);
+
+      __ evpermb(xmm4, k0, xmm20, xmm0, false, Assembler::AVX_512bit);
+      __ evpermb(xmm5, k0, xmm20, xmm1, false, Assembler::AVX_512bit);
+      __ evpermb(xmm6, k0, xmm20, xmm2, false, Assembler::AVX_512bit);
+      __ evpermb(xmm7, k0, xmm20, xmm3, false, Assembler::AVX_512bit);
+
+      __ evpsrlvw(xmm4, xmm4, xmm21, Assembler::AVX_512bit);
+      __ evpsrlvw(xmm5, xmm5, xmm21, Assembler::AVX_512bit);
+      __ evpsrlvw(xmm6, xmm6, xmm21, Assembler::AVX_512bit);
+      __ evpsrlvw(xmm7, xmm7, xmm21, Assembler::AVX_512bit);
+
+      __ evpandq(xmm0, xmm22, xmm4, Assembler::AVX_512bit);
+      __ evpandq(xmm1, xmm22, xmm5, Assembler::AVX_512bit);
+      __ evpandq(xmm2, xmm22, xmm6, Assembler::AVX_512bit);
+      __ evpandq(xmm3, xmm22, xmm7, Assembler::AVX_512bit);
+
+      store4regs(parsed, 0, xmm0_3, _masm);
+
+      __ addptr(condensed, 192);
+      __ addptr(parsed, 256);
+      __ subl(parsedLength, 128);
+      __ jcc(Assembler::greater, VBMILoop);
+
+    __ leave(); // required for proper stackwalking of RuntimeStub frame
+    __ mov64(rax, 0); // return 0
+    __ ret(0);
+
+    return start;
+  }
+
   __ lea(perms, ExternalAddress(kyberAvx512_12To16PermsAddr()));
 
   load4regs(xmm24_27, perms, 0, _masm);

src/hotspot/cpu/x86/templateTable_x86.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -2216,7 +2216,8 @@ void TemplateTable::resolve_cache_and_index_for_method(int byte_no,
   __ cmpl(temp, code);  // have we resolved this bytecode?
 
   // Class initialization barrier for static methods
-  if (VM_Version::supports_fast_class_init_checks() && bytecode() == Bytecodes::_invokestatic) {
+  if (bytecode() == Bytecodes::_invokestatic) {
+    assert(VM_Version::supports_fast_class_init_checks(), "sanity");
     const Register method = temp;
     const Register klass  = temp;
 
@@ -2264,8 +2265,8 @@ void TemplateTable::resolve_cache_and_index_for_field(int byte_no,
   __ cmpl(temp, code);  // have we resolved this bytecode?
 
   // Class initialization barrier for static fields
-  if (VM_Version::supports_fast_class_init_checks() &&
-      (bytecode() == Bytecodes::_getstatic || bytecode() == Bytecodes::_putstatic)) {
+  if (bytecode() == Bytecodes::_getstatic || bytecode() == Bytecodes::_putstatic) {
+    assert(VM_Version::supports_fast_class_init_checks(), "sanity");
     const Register field_holder = temp;
 
     __ jcc(Assembler::notEqual, L_clinit_barrier_slow);

src/hotspot/cpu/x86/vmreg_x86.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2006, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2006, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -32,9 +32,7 @@ void VMRegImpl::set_regName() {
   int i;
   for (i = 0; i < ConcreteRegisterImpl::max_gpr ; ) {
     regName[i++] = reg->name();
-#ifdef AMD64
     regName[i++] = reg->name();
-#endif // AMD64
     reg = reg->successor();
   }
 

src/hotspot/cpu/x86/vmreg_x86.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2006, 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2006, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -52,14 +52,8 @@ inline bool is_KRegister() {
 }
 
 inline Register as_Register() {
-
-  assert( is_Register(), "must be");
-  // Yuk
-#ifdef AMD64
+  assert(is_Register(), "must be");
   return ::as_Register(value() >> 1);
-#else
-  return ::as_Register(value());
-#endif // AMD64
 }
 
 inline FloatRegister as_FloatRegister() {
@@ -82,9 +76,6 @@ inline KRegister as_KRegister() {
 
 inline   bool is_concrete() {
   assert(is_reg(), "must be");
-#ifndef AMD64
-  if (is_Register()) return true;
-#endif // AMD64
   // Do not use is_XMMRegister() here as it depends on the UseAVX setting.
   if (value() >= ConcreteRegisterImpl::max_fpr && value() < ConcreteRegisterImpl::max_xmm) {
     int base = value() - ConcreteRegisterImpl::max_fpr;

src/hotspot/cpu/x86/vmreg_x86.inline.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2006, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2006, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -26,7 +26,7 @@
 #define CPU_X86_VMREG_X86_INLINE_HPP
 
 inline VMReg Register::RegisterImpl::as_VMReg() const {
-  return VMRegImpl::as_VMReg(encoding() LP64_ONLY( << 1 ));
+  return VMRegImpl::as_VMReg(encoding() << 1);
 }
 
 inline VMReg FloatRegister::FloatRegisterImpl::as_VMReg() const {

src/hotspot/cpu/x86/x86.ad

@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2011, 2025, Oracle and/or its affiliates. All rights reserved.
+// Copyright (c) 2011, 2026, Oracle and/or its affiliates. All rights reserved.
 // DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 //
 // This code is free software; you can redistribute it and/or modify it
@@ -2633,17 +2633,19 @@ bool Matcher::supports_vector_calling_convention(void) {
   return EnableVectorSupport;
 }
 
+static bool is_ndd_demotable_opr1(const MachNode* mdef) {
+  return ((mdef->flags() & Node::PD::Flag_ndd_demotable_opr1) != 0);
+}
+
+static bool is_ndd_demotable_opr2(const MachNode* mdef) {
+  return ((mdef->flags() & Node::PD::Flag_ndd_demotable_opr2) != 0);
+}
+
+#ifdef ASSERT
 static bool is_ndd_demotable(const MachNode* mdef) {
-  return ((mdef->flags() & Node::PD::Flag_ndd_demotable) != 0);
-}
-
-static bool is_ndd_demotable_commutative(const MachNode* mdef) {
-  return ((mdef->flags() & Node::PD::Flag_ndd_demotable_commutative) != 0);
-}
-
-static bool is_demotion_candidate(const MachNode* mdef) {
-  return (is_ndd_demotable(mdef) || is_ndd_demotable_commutative(mdef));
+  return (is_ndd_demotable_opr1(mdef) || is_ndd_demotable_opr2(mdef));
 }
+#endif
 
 bool Matcher::is_register_biasing_candidate(const MachNode* mdef,
                                             int oper_index) {
@@ -2653,8 +2655,8 @@ bool Matcher::is_register_biasing_candidate(const MachNode* mdef,
 
   if (mdef->num_opnds() <= oper_index || mdef->operand_index(oper_index) < 0 ||
       mdef->in(mdef->operand_index(oper_index)) == nullptr) {
-    assert(oper_index != 1 || !is_demotion_candidate(mdef), "%s", mdef->Name());
-    assert(oper_index != 2 || !is_ndd_demotable_commutative(mdef), "%s", mdef->Name());
+    assert(oper_index != 1 || !is_ndd_demotable_opr1(mdef), "%s", mdef->Name());
+    assert(oper_index != 2 || !is_ndd_demotable_opr2(mdef), "%s", mdef->Name());
     return false;
   }
 
@@ -2662,14 +2664,13 @@ bool Matcher::is_register_biasing_candidate(const MachNode* mdef,
   // address computation. Biasing def towards any address component will not
   // result in NDD demotion by assembler.
   if (mdef->operand_num_edges(oper_index) != 1) {
-    assert(!is_ndd_demotable(mdef), "%s", mdef->Name());
     return false;
   }
 
   // Demotion candidate must be register mask compatible with definition.
   const RegMask& oper_mask = mdef->in_RegMask(mdef->operand_index(oper_index));
   if (!oper_mask.overlap(mdef->out_RegMask())) {
-    assert(!is_demotion_candidate(mdef), "%s", mdef->Name());
+    assert(!is_ndd_demotable(mdef), "%s", mdef->Name());
     return false;
   }
 
@@ -2681,12 +2682,12 @@ bool Matcher::is_register_biasing_candidate(const MachNode* mdef,
   // EVEX prefix with shorter REX/REX2 encoding. Demotion candidates
   // are decorated with a special flag by instruction selector.
   case 1:
-    return is_demotion_candidate(mdef);
+    return is_ndd_demotable_opr1(mdef);
 
   // Definition operand of commutative operation can be biased towards second
   // operand.
   case 2:
-    return is_ndd_demotable_commutative(mdef);
+    return is_ndd_demotable_opr2(mdef);
 
   // Current scheme only selects up to two biasing candidates
   default:
@@ -2888,9 +2889,9 @@ public:
     Flag_clears_zero_flag     = Node::_last_flag << 9,
     Flag_clears_overflow_flag = Node::_last_flag << 10,
     Flag_clears_sign_flag     = Node::_last_flag << 11,
-    Flag_ndd_demotable        = Node::_last_flag << 12,
-    Flag_ndd_demotable_commutative = Node::_last_flag << 13,
-    _last_flag                = Flag_ndd_demotable_commutative
+    Flag_ndd_demotable_opr1   = Node::_last_flag << 12,
+    Flag_ndd_demotable_opr2   = Node::_last_flag << 13,
+    _last_flag                = Flag_ndd_demotable_opr2
   };
 };
 
@@ -9872,7 +9873,7 @@ instruct addI_rReg_ndd(rRegI dst, rRegI src1, rRegI src2, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (AddI src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable_commutative);
+  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable_opr1, PD::Flag_ndd_demotable_opr2);
 
   format %{ "eaddl    $dst, $src1, $src2\t# int ndd" %}
   ins_encode %{
@@ -9900,7 +9901,7 @@ instruct addI_rReg_rReg_imm_ndd(rRegI dst, rRegI src1, immI src2, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (AddI src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable);
+  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable_opr1);
 
   format %{ "eaddl    $dst, $src1, $src2\t# int ndd" %}
   ins_encode %{
@@ -9943,7 +9944,7 @@ instruct addI_rReg_rReg_mem_ndd(rRegI dst, rRegI src1, memory src2, rFlagsReg cr
   predicate(UseAPX);
   match(Set dst (AddI src1 (LoadI src2)));
   effect(KILL cr);
-  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable_commutative);
+  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable_opr1, PD::Flag_ndd_demotable_opr2);
 
   ins_cost(150);
   format %{ "eaddl    $dst, $src1, $src2\t# int ndd" %}
@@ -10000,7 +10001,7 @@ instruct incI_rReg_ndd(rRegI dst, rRegI src, immI_1 val, rFlagsReg cr)
   predicate(UseAPX && UseIncDec);
   match(Set dst (AddI src val));
   effect(KILL cr);
-  flag(PD::Flag_ndd_demotable);
+  flag(PD::Flag_ndd_demotable_opr1);
 
   format %{ "eincl    $dst, $src\t# int ndd" %}
   ins_encode %{
@@ -10055,7 +10056,7 @@ instruct decI_rReg_ndd(rRegI dst, rRegI src, immI_M1 val, rFlagsReg cr)
   predicate(UseAPX && UseIncDec);
   match(Set dst (AddI src val));
   effect(KILL cr);
-  flag(PD::Flag_ndd_demotable);
+  flag(PD::Flag_ndd_demotable_opr1);
 
   format %{ "edecl    $dst, $src\t# int ndd" %}
   ins_encode %{
@@ -10162,7 +10163,7 @@ instruct addL_rReg_ndd(rRegL dst, rRegL src1, rRegL src2, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (AddL src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable_commutative);
+  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable_opr1, PD::Flag_ndd_demotable_opr2);
 
   format %{ "eaddq    $dst, $src1, $src2\t# long ndd" %}
   ins_encode %{
@@ -10190,7 +10191,7 @@ instruct addL_rReg_rReg_imm_ndd(rRegL dst, rRegL src1, immL32 src2, rFlagsReg cr
   predicate(UseAPX);
   match(Set dst (AddL src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable);
+  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable_opr1);
 
   format %{ "eaddq    $dst, $src1, $src2\t# long ndd" %}
   ins_encode %{
@@ -10233,7 +10234,7 @@ instruct addL_rReg_rReg_mem_ndd(rRegL dst, rRegL src1, memory src2, rFlagsReg cr
   predicate(UseAPX);
   match(Set dst (AddL src1 (LoadL src2)));
   effect(KILL cr);
-  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable_commutative);
+  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable_opr1, PD::Flag_ndd_demotable_opr2);
 
   ins_cost(150);
   format %{ "eaddq    $dst, $src1, $src2\t# long ndd" %}
@@ -10289,7 +10290,7 @@ instruct incL_rReg_ndd(rRegL dst, rRegI src, immL1 val, rFlagsReg cr)
   predicate(UseAPX && UseIncDec);
   match(Set dst (AddL src val));
   effect(KILL cr);
-  flag(PD::Flag_ndd_demotable);
+  flag(PD::Flag_ndd_demotable_opr1);
 
   format %{ "eincq    $dst, $src\t# long ndd" %}
   ins_encode %{
@@ -10344,7 +10345,7 @@ instruct decL_rReg_ndd(rRegL dst, rRegL src, immL_M1 val, rFlagsReg cr)
   predicate(UseAPX && UseIncDec);
   match(Set dst (AddL src val));
   effect(KILL cr);
-  flag(PD::Flag_ndd_demotable);
+  flag(PD::Flag_ndd_demotable_opr1);
 
   format %{ "edecq    $dst, $src\t# long ndd" %}
   ins_encode %{
@@ -11059,7 +11060,7 @@ instruct subI_rReg_ndd(rRegI dst, rRegI src1, rRegI src2, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (SubI src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable);
+  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable_opr1);
 
   format %{ "esubl    $dst, $src1, $src2\t# int ndd" %}
   ins_encode %{
@@ -11073,7 +11074,7 @@ instruct subI_rReg_rReg_imm_ndd(rRegI dst, rRegI src1, immI src2, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (SubI src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable);
+  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable_opr1);
 
   format %{ "esubl    $dst, $src1, $src2\t# int ndd" %}
   ins_encode %{
@@ -11116,7 +11117,7 @@ instruct subI_rReg_rReg_mem_ndd(rRegI dst, rRegI src1, memory src2, rFlagsReg cr
   predicate(UseAPX);
   match(Set dst (SubI src1 (LoadI src2)));
   effect(KILL cr);
-  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable);
+  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable_opr1);
 
   ins_cost(150);
   format %{ "esubl    $dst, $src1, $src2\t# int ndd" %}
@@ -11174,7 +11175,7 @@ instruct subL_rReg_ndd(rRegL dst, rRegL src1, rRegL src2, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (SubL src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable);
+  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable_opr1);
 
   format %{ "esubq    $dst, $src1, $src2\t# long ndd" %}
   ins_encode %{
@@ -11188,7 +11189,7 @@ instruct subL_rReg_rReg_imm_ndd(rRegL dst, rRegL src1, immL32 src2, rFlagsReg cr
   predicate(UseAPX);
   match(Set dst (SubL src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable);
+  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable_opr1);
 
   format %{ "esubq    $dst, $src1, $src2\t# long ndd" %}
   ins_encode %{
@@ -11231,7 +11232,7 @@ instruct subL_rReg_rReg_mem_ndd(rRegL dst, rRegL src1, memory src2, rFlagsReg cr
   predicate(UseAPX);
   match(Set dst (SubL src1 (LoadL src2)));
   effect(KILL cr);
-  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable);
+  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_carry_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable_opr1);
 
   ins_cost(150);
   format %{ "esubq    $dst, $src1, $src2\t# long ndd" %}
@@ -11303,7 +11304,7 @@ instruct negI_rReg_ndd(rRegI dst, rRegI src, immI_0 zero, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (SubI zero src));
   effect(KILL cr);
-  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable);
+  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable_opr2);
 
   format %{ "enegl    $dst, $src\t# int ndd" %}
   ins_encode %{
@@ -11331,7 +11332,7 @@ instruct negI_rReg_2_ndd(rRegI dst, rRegI src, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (NegI src));
   effect(KILL cr);
-  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable);
+  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable_opr1);
 
   format %{ "enegl    $dst, $src\t# int ndd" %}
   ins_encode %{
@@ -11372,7 +11373,7 @@ instruct negL_rReg_ndd(rRegL dst, rRegL src, immL0 zero, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (SubL zero src));
   effect(KILL cr);
-  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable);
+  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable_opr2);
 
   format %{ "enegq    $dst, $src\t# long ndd" %}
   ins_encode %{
@@ -11400,7 +11401,7 @@ instruct negL_rReg_2_ndd(rRegL dst, rRegL src, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (NegL src));
   effect(KILL cr);
-  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable);
+  flag(PD::Flag_sets_overflow_flag, PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_ndd_demotable_opr1);
 
   format %{ "enegq    $dst, $src\t# long ndd" %}
   ins_encode %{
@@ -11445,7 +11446,7 @@ instruct mulI_rReg_ndd(rRegI dst, rRegI src1, rRegI src2, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (MulI src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_ndd_demotable_commutative);
+  flag(PD::Flag_ndd_demotable_opr1, PD::Flag_ndd_demotable_opr2);
 
   ins_cost(300);
   format %{ "eimull   $dst, $src1, $src2\t# int ndd" %}
@@ -11487,7 +11488,7 @@ instruct mulI_rReg_rReg_mem_ndd(rRegI dst, rRegI src1, memory src2, rFlagsReg cr
   predicate(UseAPX);
   match(Set dst (MulI src1 (LoadI src2)));
   effect(KILL cr);
-  flag(PD::Flag_ndd_demotable);
+  flag(PD::Flag_ndd_demotable_opr1, PD::Flag_ndd_demotable_opr2);
 
   ins_cost(350);
   format %{ "eimull   $dst, $src1, $src2\t# int ndd" %}
@@ -11539,7 +11540,7 @@ instruct mulL_rReg_ndd(rRegL dst, rRegL src1, rRegL src2, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (MulL src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_ndd_demotable_commutative);
+  flag(PD::Flag_ndd_demotable_opr1, PD::Flag_ndd_demotable_opr2);
 
   ins_cost(300);
   format %{ "eimulq   $dst, $src1, $src2\t# long ndd" %}
@@ -11581,7 +11582,7 @@ instruct mulL_rReg_rReg_mem_ndd(rRegL dst, rRegL src1, memory src2, rFlagsReg cr
   predicate(UseAPX);
   match(Set dst (MulL src1 (LoadL src2)));
   effect(KILL cr);
-  flag(PD::Flag_ndd_demotable_commutative);
+  flag(PD::Flag_ndd_demotable_opr1, PD::Flag_ndd_demotable_opr2);
 
   ins_cost(350);
   format %{ "eimulq   $dst, $src1, $src2 \t# long" %}
@@ -11856,7 +11857,7 @@ instruct salI_rReg_immI2_ndd(rRegI dst, rRegI src, immI2 shift, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (LShiftI src shift));
   effect(KILL cr);
-  flag(PD::Flag_ndd_demotable);
+  flag(PD::Flag_ndd_demotable_opr1);
 
   format %{ "esall    $dst, $src, $shift\t# int(ndd)" %}
   ins_encode %{
@@ -11885,7 +11886,7 @@ instruct salI_rReg_imm_ndd(rRegI dst, rRegI src, immI8 shift, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (LShiftI src shift));
   effect(KILL cr);
-  flag(PD::Flag_ndd_demotable);
+  flag(PD::Flag_ndd_demotable_opr1);
 
   format %{ "esall    $dst, $src, $shift\t# int (ndd)" %}
   ins_encode %{
@@ -11992,7 +11993,7 @@ instruct sarI_rReg_imm_ndd(rRegI dst, rRegI src, immI8 shift, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (RShiftI src shift));
   effect(KILL cr);
-  flag(PD::Flag_ndd_demotable);
+  flag(PD::Flag_ndd_demotable_opr1);
 
   format %{ "esarl    $dst, $src, $shift\t# int (ndd)" %}
   ins_encode %{
@@ -12099,7 +12100,7 @@ instruct shrI_rReg_imm_ndd(rRegI dst, rRegI src, immI8 shift, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (URShiftI src shift));
   effect(KILL cr);
-  flag(PD::Flag_ndd_demotable);
+  flag(PD::Flag_ndd_demotable_opr1);
 
   format %{ "eshrl    $dst, $src, $shift\t # int (ndd)" %}
   ins_encode %{
@@ -12207,7 +12208,7 @@ instruct salL_rReg_immI2_ndd(rRegL dst, rRegL src, immI2 shift, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (LShiftL src shift));
   effect(KILL cr);
-  flag(PD::Flag_ndd_demotable);
+  flag(PD::Flag_ndd_demotable_opr1);
 
   format %{ "esalq    $dst, $src, $shift\t# long (ndd)" %}
   ins_encode %{
@@ -12236,7 +12237,7 @@ instruct salL_rReg_imm_ndd(rRegL dst, rRegL src, immI8 shift, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (LShiftL src shift));
   effect(KILL cr);
-  flag(PD::Flag_ndd_demotable);
+  flag(PD::Flag_ndd_demotable_opr1);
 
   format %{ "esalq    $dst, $src, $shift\t# long (ndd)" %}
   ins_encode %{
@@ -12343,7 +12344,7 @@ instruct sarL_rReg_imm_ndd(rRegL dst, rRegL src, immI shift, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (RShiftL src shift));
   effect(KILL cr);
-  flag(PD::Flag_ndd_demotable);
+  flag(PD::Flag_ndd_demotable_opr1);
 
   format %{ "esarq    $dst, $src, $shift\t# long (ndd)" %}
   ins_encode %{
@@ -12450,7 +12451,7 @@ instruct shrL_rReg_imm_ndd(rRegL dst, rRegL src, immI8 shift, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (URShiftL src shift));
   effect(KILL cr);
-  flag(PD::Flag_ndd_demotable);
+  flag(PD::Flag_ndd_demotable_opr1);
 
   format %{ "eshrq    $dst, $src, $shift\t# long (ndd)" %}
   ins_encode %{
@@ -12622,7 +12623,7 @@ instruct rolI_rReg_Var_ndd(rRegI dst, rRegI src, rcx_RegI shift, rFlagsReg cr)
   predicate(UseAPX && n->bottom_type()->basic_type() == T_INT);
   match(Set dst (RotateLeft src shift));
   effect(KILL cr);
-  flag(PD::Flag_ndd_demotable);
+  flag(PD::Flag_ndd_demotable_opr1);
 
   format %{ "eroll    $dst, $src, $shift\t# rotate left (int ndd)" %}
   ins_encode %{
@@ -12687,7 +12688,7 @@ instruct rorI_rReg_Var_ndd(rRegI dst, rRegI src, rcx_RegI shift, rFlagsReg cr)
   predicate(UseAPX && n->bottom_type()->basic_type() == T_INT);
   match(Set dst (RotateRight src shift));
   effect(KILL cr);
-  flag(PD::Flag_ndd_demotable);
+  flag(PD::Flag_ndd_demotable_opr1);
 
   format %{ "erorl    $dst, $src, $shift\t# rotate right(int ndd)" %}
   ins_encode %{
@@ -12754,7 +12755,7 @@ instruct rolL_rReg_Var_ndd(rRegL dst, rRegL src, rcx_RegI shift, rFlagsReg cr)
   predicate(UseAPX && n->bottom_type()->basic_type() == T_LONG);
   match(Set dst (RotateLeft src shift));
   effect(KILL cr);
-  flag(PD::Flag_ndd_demotable);
+  flag(PD::Flag_ndd_demotable_opr1);
 
   format %{ "erolq    $dst, $src, $shift\t# rotate left(long ndd)" %}
   ins_encode %{
@@ -12819,7 +12820,7 @@ instruct rorL_rReg_Var_ndd(rRegL dst, rRegL src, rcx_RegI shift, rFlagsReg cr)
   predicate(UseAPX && n->bottom_type()->basic_type() == T_LONG);
   match(Set dst (RotateRight src shift));
   effect(KILL cr);
-  flag(PD::Flag_ndd_demotable);
+  flag(PD::Flag_ndd_demotable_opr1);
 
   format %{ "erorq    $dst, $src, $shift\t# rotate right(long ndd)" %}
   ins_encode %{
@@ -12897,7 +12898,7 @@ instruct andI_rReg_ndd(rRegI dst, rRegI src1, rRegI src2, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (AndI src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_commutative);
+  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_opr1, PD::Flag_ndd_demotable_opr2);
 
   format %{ "eandl     $dst, $src1, $src2\t# int ndd" %}
   ins_encode %{
@@ -12990,7 +12991,7 @@ instruct andI_rReg_rReg_imm_ndd(rRegI dst, rRegI src1, immI src2, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (AndI src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable);
+  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_opr1);
 
   format %{ "eandl    $dst, $src1, $src2\t# int ndd" %}
   ins_encode %{
@@ -13034,7 +13035,7 @@ instruct andI_rReg_rReg_mem_ndd(rRegI dst, rRegI src1, memory src2, rFlagsReg cr
   predicate(UseAPX);
   match(Set dst (AndI src1 (LoadI src2)));
   effect(KILL cr);
-  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_commutative);
+  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_opr1, PD::Flag_ndd_demotable_opr2);
 
   ins_cost(150);
   format %{ "eandl    $dst, $src1, $src2\t# int ndd" %}
@@ -13234,7 +13235,7 @@ instruct orI_rReg_ndd(rRegI dst, rRegI src1, rRegI src2, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (OrI src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_commutative);
+  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_opr1, PD::Flag_ndd_demotable_opr2);
 
   format %{ "eorl     $dst, $src1, $src2\t# int ndd" %}
   ins_encode %{
@@ -13263,7 +13264,7 @@ instruct orI_rReg_rReg_imm_ndd(rRegI dst, rRegI src1, immI src2, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (OrI src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable);
+  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_opr1);
 
   format %{ "eorl     $dst, $src1, $src2\t# int ndd" %}
   ins_encode %{
@@ -13277,7 +13278,7 @@ instruct orI_rReg_imm_rReg_ndd(rRegI dst, immI src1, rRegI src2, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (OrI src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable);
+  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_opr1);
 
   format %{ "eorl     $dst, $src2, $src1\t# int ndd" %}
   ins_encode %{
@@ -13321,7 +13322,7 @@ instruct orI_rReg_rReg_mem_ndd(rRegI dst, rRegI src1, memory src2, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (OrI src1 (LoadI src2)));
   effect(KILL cr);
-  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable);
+  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_opr1, PD::Flag_ndd_demotable_opr2);
 
   ins_cost(150);
   format %{ "eorl     $dst, $src1, $src2\t# int ndd" %}
@@ -13397,7 +13398,7 @@ instruct xorI_rReg_ndd(rRegI dst, rRegI src1, rRegI src2, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (XorI src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_commutative);
+  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_opr1, PD::Flag_ndd_demotable_opr2);
 
   format %{ "exorl    $dst, $src1, $src2\t# int ndd" %}
   ins_encode %{
@@ -13423,7 +13424,7 @@ instruct xorI_rReg_im1_ndd(rRegI dst, rRegI src, immI_M1 imm)
 %{
   match(Set dst (XorI src imm));
   predicate(UseAPX);
-  flag(PD::Flag_ndd_demotable);
+  flag(PD::Flag_ndd_demotable_opr1);
 
   format %{ "enotl    $dst, $src" %}
   ins_encode %{
@@ -13454,7 +13455,7 @@ instruct xorI_rReg_rReg_imm_ndd(rRegI dst, rRegI src1, immI src2, rFlagsReg cr)
   predicate(UseAPX && n->in(2)->bottom_type()->is_int()->get_con() != -1);
   match(Set dst (XorI src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable);
+  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_opr1);
 
   format %{ "exorl    $dst, $src1, $src2\t# int ndd" %}
   ins_encode %{
@@ -13500,7 +13501,7 @@ instruct xorI_rReg_rReg_mem_ndd(rRegI dst, rRegI src1, memory src2, rFlagsReg cr
   predicate(UseAPX);
   match(Set dst (XorI src1 (LoadI src2)));
   effect(KILL cr);
-  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable);
+  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_opr1, PD::Flag_ndd_demotable_opr2);
 
   ins_cost(150);
   format %{ "exorl    $dst, $src1, $src2\t# int ndd" %}
@@ -13579,7 +13580,7 @@ instruct andL_rReg_ndd(rRegL dst, rRegL src1, rRegL src2, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (AndL src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_commutative);
+  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_opr1, PD::Flag_ndd_demotable_opr2);
 
   format %{ "eandq     $dst, $src1, $src2\t# long ndd" %}
   ins_encode %{
@@ -13635,7 +13636,7 @@ instruct andL_rReg_rReg_imm_ndd(rRegL dst, rRegL src1, immL32 src2, rFlagsReg cr
   predicate(UseAPX);
   match(Set dst (AndL src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable);
+  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_opr1);
 
   format %{ "eandq    $dst, $src1, $src2\t# long ndd" %}
   ins_encode %{
@@ -13679,7 +13680,7 @@ instruct andL_rReg_rReg_mem_ndd(rRegL dst, rRegL src1, memory src2, rFlagsReg cr
   predicate(UseAPX);
   match(Set dst (AndL src1 (LoadL src2)));
   effect(KILL cr);
-  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_commutative);
+  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_opr1, PD::Flag_ndd_demotable_opr2);
 
   ins_cost(150);
   format %{ "eandq    $dst, $src1, $src2\t# long ndd" %}
@@ -13882,7 +13883,7 @@ instruct orL_rReg_ndd(rRegL dst, rRegL src1, rRegL src2, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (OrL src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_commutative);
+  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_opr1, PD::Flag_ndd_demotable_opr2);
 
   format %{ "eorq     $dst, $src1, $src2\t# long ndd" %}
   ins_encode %{
@@ -13937,7 +13938,7 @@ instruct orL_rReg_rReg_imm_ndd(rRegL dst, rRegL src1, immL32 src2, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (OrL src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable);
+  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_opr1);
 
   format %{ "eorq     $dst, $src1, $src2\t# long ndd" %}
   ins_encode %{
@@ -13951,7 +13952,7 @@ instruct orL_rReg_imm_rReg_ndd(rRegL dst, immL32 src1, rRegL src2, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (OrL src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable);
+  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_opr1);
 
   format %{ "eorq     $dst, $src2, $src1\t# long ndd" %}
   ins_encode %{
@@ -13996,7 +13997,7 @@ instruct orL_rReg_rReg_mem_ndd(rRegL dst, rRegL src1, memory src2, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (OrL src1 (LoadL src2)));
   effect(KILL cr);
-  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_commutative);
+  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_opr1, PD::Flag_ndd_demotable_opr2);
 
   ins_cost(150);
   format %{ "eorq     $dst, $src1, $src2\t# long ndd" %}
@@ -14075,7 +14076,7 @@ instruct xorL_rReg_ndd(rRegL dst, rRegL src1, rRegL src2, rFlagsReg cr)
   predicate(UseAPX);
   match(Set dst (XorL src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_commutative);
+  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_opr1, PD::Flag_ndd_demotable_opr2);
 
   format %{ "exorq    $dst, $src1, $src2\t# long ndd" %}
   ins_encode %{
@@ -14101,7 +14102,7 @@ instruct xorL_rReg_im1_ndd(rRegL dst,rRegL src, immL_M1 imm)
 %{
   predicate(UseAPX);
   match(Set dst (XorL src imm));
-  flag(PD::Flag_ndd_demotable);
+  flag(PD::Flag_ndd_demotable_opr1);
 
   format %{ "enotq   $dst, $src" %}
   ins_encode %{
@@ -14132,7 +14133,7 @@ instruct xorL_rReg_rReg_imm(rRegL dst, rRegL src1, immL32 src2, rFlagsReg cr)
   predicate(UseAPX && n->in(2)->bottom_type()->is_long()->get_con() != -1L);
   match(Set dst (XorL src1 src2));
   effect(KILL cr);
-  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable);
+  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_opr1);
 
   format %{ "exorq    $dst, $src1, $src2\t# long ndd" %}
   ins_encode %{
@@ -14178,7 +14179,7 @@ instruct xorL_rReg_rReg_mem_ndd(rRegL dst, rRegL src1, memory src2, rFlagsReg cr
   predicate(UseAPX);
   match(Set dst (XorL src1 (LoadL src2)));
   effect(KILL cr);
-  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_commutative);
+  flag(PD::Flag_sets_sign_flag, PD::Flag_sets_zero_flag, PD::Flag_sets_parity_flag, PD::Flag_clears_overflow_flag, PD::Flag_clears_carry_flag, PD::Flag_ndd_demotable_opr1, PD::Flag_ndd_demotable_opr2);
 
   ins_cost(150);
   format %{ "exorq    $dst, $src1, $src2\t# long ndd" %}
@@ -16633,7 +16634,7 @@ instruct minI_rReg_ndd(rRegI dst, rRegI src1, rRegI src2)
   predicate(UseAPX);
   match(Set dst (MinI src1 src2));
   effect(DEF dst, USE src1, USE src2);
-  flag(PD::Flag_ndd_demotable);
+  flag(PD::Flag_ndd_demotable_opr1);
 
   ins_cost(200);
   expand %{
@@ -16685,7 +16686,7 @@ instruct maxI_rReg_ndd(rRegI dst, rRegI src1, rRegI src2)
   predicate(UseAPX);
   match(Set dst (MaxI src1 src2));
   effect(DEF dst, USE src1, USE src2);
-  flag(PD::Flag_ndd_demotable);
+  flag(PD::Flag_ndd_demotable_opr1);
 
   ins_cost(200);
   expand %{

src/hotspot/os/aix/libodm_aix.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2015, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2015, 2019 SAP SE. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -23,15 +23,15 @@
  *
  */
 
+#include "cppstdlib/cstdlib.hpp"
 #include "libodm_aix.hpp"
 #include "misc_aix.hpp"
-#include <stdlib.h>
-#include <dlfcn.h>
-#include <string.h>
 #include "runtime/arguments.hpp"
 #include "runtime/os.hpp"
 #include "utilities/permitForbiddenFunctions.hpp"
 
+#include <dlfcn.h>
+#include <string.h>
 
 dynamicOdm::dynamicOdm() {
   const char* libodmname = "/usr/lib/libodm.a(shr_64.o)";

src/hotspot/os/aix/libperfstat_aix.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2022, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2012, 2024 SAP SE. All rights reserved.
  * Copyright (c) 2022, IBM Corp.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
@@ -32,8 +32,9 @@
 #ifndef OS_AIX_LIBPERFSTAT_AIX_HPP
 #define OS_AIX_LIBPERFSTAT_AIX_HPP
 
+#include "cppstdlib/cstdlib.hpp"
+
 #include <sys/types.h>
-#include <stdlib.h>
 
 ///////////////////////////////////////////////////////////////////////////////////////////////
 // These are excerpts from the AIX 7.1 libperfstat.h -

src/hotspot/os/aix/os_aix.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2012, 2025 SAP SE. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -258,10 +258,18 @@ bool os::free_memory(physical_memory_size_type& value) {
   return Aix::available_memory(value);
 }
 
+bool os::Machine::free_memory(physical_memory_size_type& value) {
+  return Aix::available_memory(value);
+}
+
 bool os::available_memory(physical_memory_size_type& value) {
   return Aix::available_memory(value);
 }
 
+bool os::Machine::available_memory(physical_memory_size_type& value) {
+  return Aix::available_memory(value);
+}
+
 bool os::Aix::available_memory(physical_memory_size_type& value) {
   os::Aix::meminfo_t mi;
   if (os::Aix::get_meminfo(&mi)) {
@@ -273,6 +281,10 @@ bool os::Aix::available_memory(physical_memory_size_type& value) {
 }
 
 bool os::total_swap_space(physical_memory_size_type& value) {
+  return Machine::total_swap_space(value);
+}
+
+bool os::Machine::total_swap_space(physical_memory_size_type& value) {
   perfstat_memory_total_t memory_info;
   if (libperfstat::perfstat_memory_total(nullptr, &memory_info, sizeof(perfstat_memory_total_t), 1) == -1) {
     return false;
@@ -282,6 +294,10 @@ bool os::total_swap_space(physical_memory_size_type& value) {
 }
 
 bool os::free_swap_space(physical_memory_size_type& value) {
+  return Machine::free_swap_space(value);
+}
+
+bool os::Machine::free_swap_space(physical_memory_size_type& value) {
   perfstat_memory_total_t memory_info;
   if (libperfstat::perfstat_memory_total(nullptr, &memory_info, sizeof(perfstat_memory_total_t), 1) == -1) {
     return false;
@@ -294,6 +310,10 @@ physical_memory_size_type os::physical_memory() {
   return Aix::physical_memory();
 }
 
+physical_memory_size_type os::Machine::physical_memory() {
+  return Aix::physical_memory();
+}
+
 size_t os::rss() { return (size_t)0; }
 
 // Cpu architecture string
@@ -2264,6 +2284,10 @@ int os::active_processor_count() {
     return ActiveProcessorCount;
   }
 
+  return Machine::active_processor_count();
+}
+
+int os::Machine::active_processor_count() {
   int online_cpus = ::sysconf(_SC_NPROCESSORS_ONLN);
   assert(online_cpus > 0 && online_cpus <= processor_count(), "sanity check");
   return online_cpus;

src/hotspot/os/aix/os_perf_aix.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2022, 2024, IBM Corp.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -23,6 +23,7 @@
  *
  */
 
+#include "cppstdlib/cstdlib.hpp"
 #include "jvm.h"
 #include "libperfstat_aix.hpp"
 #include "memory/allocation.inline.hpp"
@@ -46,7 +47,6 @@
 #include <sys/resource.h>
 #include <sys/stat.h>
 #include <sys/types.h>
-#include <stdlib.h>
 #include <unistd.h>
 
 typedef struct {

src/hotspot/os/bsd/memMapPrinter_macosx.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2023, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2023, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2023, 2024, Red Hat, Inc. and/or its affiliates.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -25,6 +25,7 @@
 
 #if defined(__APPLE__)
 
+#include "cppstdlib/cstdlib.hpp"
 #include "nmt/memMapPrinter.hpp"
 #include "runtime/os.hpp"
 #include "utilities/align.hpp"
@@ -34,7 +35,6 @@
 
 #include <limits.h>
 #include <stdio.h>
-#include <stdlib.h>
 #include <libproc.h>
 #include <unistd.h>
 
@@ -132,7 +132,7 @@ public:
   static const char* tagToStr(uint32_t user_tag) {
     switch (user_tag) {
       case 0:
-        return 0;
+        return nullptr;
       X1(MALLOC, malloc);
       X1(MALLOC_SMALL, malloc_small);
       X1(MALLOC_LARGE, malloc_large);

src/hotspot/os/bsd/os_bsd.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -137,10 +137,18 @@ bool os::available_memory(physical_memory_size_type& value) {
   return Bsd::available_memory(value);
 }
 
+bool os::Machine::available_memory(physical_memory_size_type& value) {
+  return Bsd::available_memory(value);
+}
+
 bool os::free_memory(physical_memory_size_type& value) {
   return Bsd::available_memory(value);
 }
 
+bool os::Machine::free_memory(physical_memory_size_type& value) {
+  return Bsd::available_memory(value);
+}
+
 // Available here means free. Note that this number is of no much use. As an estimate
 // for future memory pressure it is far too conservative, since MacOS will use a lot
 // of unused memory for caches, and return it willingly in case of needs.
@@ -181,6 +189,10 @@ void os::Bsd::print_uptime_info(outputStream* st) {
 }
 
 bool os::total_swap_space(physical_memory_size_type& value) {
+  return Machine::total_swap_space(value);
+}
+
+bool os::Machine::total_swap_space(physical_memory_size_type& value) {
 #if defined(__APPLE__)
   struct xsw_usage vmusage;
   size_t size = sizeof(vmusage);
@@ -195,6 +207,10 @@ bool os::total_swap_space(physical_memory_size_type& value) {
 }
 
 bool os::free_swap_space(physical_memory_size_type& value) {
+  return Machine::free_swap_space(value);
+}
+
+bool os::Machine::free_swap_space(physical_memory_size_type& value) {
 #if defined(__APPLE__)
   struct xsw_usage vmusage;
   size_t size = sizeof(vmusage);
@@ -212,6 +228,10 @@ physical_memory_size_type os::physical_memory() {
   return Bsd::physical_memory();
 }
 
+physical_memory_size_type os::Machine::physical_memory() {
+  return Bsd::physical_memory();
+}
+
 size_t os::rss() {
   size_t rss = 0;
 #ifdef __APPLE__
@@ -608,7 +628,7 @@ static void *thread_native_entry(Thread *thread) {
   log_info(os, thread)("Thread finished (tid: %zu, pthread id: %zu).",
     os::current_thread_id(), (uintx) pthread_self());
 
-  return 0;
+  return nullptr;
 }
 
 bool os::create_thread(Thread* thread, ThreadType thr_type,
@@ -1400,7 +1420,7 @@ int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *pa
 #elif defined(__APPLE__)
   for (uint32_t i = 1; i < _dyld_image_count(); i++) {
     // Value for top_address is returned as 0 since we don't have any information about module size
-    if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), (address)0, param)) {
+    if (callback(_dyld_get_image_name(i), (address)_dyld_get_image_header(i), nullptr, param)) {
       return 1;
     }
   }
@@ -2189,6 +2209,10 @@ int os::active_processor_count() {
     return ActiveProcessorCount;
   }
 
+  return Machine::active_processor_count();
+}
+
+int os::Machine::active_processor_count() {
   return _processor_count;
 }
 

src/hotspot/os/linux/cgroupSubsystem_linux.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2019, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -631,22 +631,20 @@ void CgroupSubsystemFactory::cleanup(CgroupInfo* cg_infos) {
  * return:
  *    true if there were no errors. false otherwise.
  */
-bool CgroupSubsystem::active_processor_count(int& value) {
-  int cpu_count;
-  int result = -1;
-
+bool CgroupSubsystem::active_processor_count(double& value) {
   // We use a cache with a timeout to avoid performing expensive
   // computations in the event this function is called frequently.
   // [See 8227006].
-  CachingCgroupController<CgroupCpuController>* contrl = cpu_controller();
-  CachedMetric* cpu_limit = contrl->metrics_cache();
+  CachingCgroupController<CgroupCpuController, double>* contrl = cpu_controller();
+  CachedMetric<double>* cpu_limit = contrl->metrics_cache();
   if (!cpu_limit->should_check_metric()) {
-    value = (int)cpu_limit->value();
-    log_trace(os, container)("CgroupSubsystem::active_processor_count (cached): %d", value);
+    value = cpu_limit->value();
+    log_trace(os, container)("CgroupSubsystem::active_processor_count (cached): %.2f", value);
     return true;
   }
 
-  cpu_count = os::Linux::active_processor_count();
+  int cpu_count = os::Linux::active_processor_count();
+  double result = -1;
   if (!CgroupUtil::processor_count(contrl->controller(), cpu_count, result)) {
     return false;
   }
@@ -671,8 +669,8 @@ bool CgroupSubsystem::active_processor_count(int& value) {
  */
 bool CgroupSubsystem::memory_limit_in_bytes(physical_memory_size_type upper_bound,
                                             physical_memory_size_type& value) {
-  CachingCgroupController<CgroupMemoryController>* contrl = memory_controller();
-  CachedMetric* memory_limit = contrl->metrics_cache();
+  CachingCgroupController<CgroupMemoryController, physical_memory_size_type>* contrl = memory_controller();
+  CachedMetric<physical_memory_size_type>* memory_limit = contrl->metrics_cache();
   if (!memory_limit->should_check_metric()) {
     value = memory_limit->value();
     return true;

src/hotspot/os/linux/cgroupSubsystem_linux.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2019, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -181,20 +181,21 @@ class CgroupController: public CHeapObj<mtInternal> {
     static bool limit_from_str(char* limit_str, physical_memory_size_type& value);
 };
 
+template <typename MetricType>
 class CachedMetric : public CHeapObj<mtInternal>{
   private:
-    volatile physical_memory_size_type _metric;
+    volatile MetricType _metric;
     volatile jlong _next_check_counter;
   public:
     CachedMetric() {
-      _metric = value_unlimited;
+      _metric = static_cast<MetricType>(value_unlimited);
       _next_check_counter = min_jlong;
     }
     bool should_check_metric() {
       return os::elapsed_counter() > _next_check_counter;
     }
-    physical_memory_size_type value() { return _metric; }
-    void set_value(physical_memory_size_type value, jlong timeout) {
+    MetricType value() { return _metric; }
+    void set_value(MetricType value, jlong timeout) {
       _metric = value;
       // Metric is unlikely to change, but we want to remain
       // responsive to configuration changes. A very short grace time
@@ -205,19 +206,19 @@ class CachedMetric : public CHeapObj<mtInternal>{
     }
 };
 
-template <class T>
+template <class T, typename MetricType>
 class CachingCgroupController : public CHeapObj<mtInternal> {
   private:
     T* _controller;
-    CachedMetric* _metrics_cache;
+    CachedMetric<MetricType>* _metrics_cache;
 
   public:
     CachingCgroupController(T* cont) {
       _controller = cont;
-      _metrics_cache = new CachedMetric();
+      _metrics_cache = new CachedMetric<MetricType>();
     }
 
-    CachedMetric* metrics_cache() { return _metrics_cache; }
+    CachedMetric<MetricType>* metrics_cache() { return _metrics_cache; }
     T* controller() { return _controller; }
 };
 
@@ -277,7 +278,7 @@ class CgroupMemoryController: public CHeapObj<mtInternal> {
 class CgroupSubsystem: public CHeapObj<mtInternal> {
   public:
     bool memory_limit_in_bytes(physical_memory_size_type upper_bound, physical_memory_size_type& value);
-    bool active_processor_count(int& value);
+    bool active_processor_count(double& value);
 
     virtual bool pids_max(uint64_t& value) = 0;
     virtual bool pids_current(uint64_t& value) = 0;
@@ -286,8 +287,8 @@ class CgroupSubsystem: public CHeapObj<mtInternal> {
     virtual char * cpu_cpuset_cpus() = 0;
     virtual char * cpu_cpuset_memory_nodes() = 0;
     virtual const char * container_type() = 0;
-    virtual CachingCgroupController<CgroupMemoryController>* memory_controller() = 0;
-    virtual CachingCgroupController<CgroupCpuController>* cpu_controller() = 0;
+    virtual CachingCgroupController<CgroupMemoryController, physical_memory_size_type>* memory_controller() = 0;
+    virtual CachingCgroupController<CgroupCpuController, double>* cpu_controller() = 0;
     virtual CgroupCpuacctController* cpuacct_controller() = 0;
 
     bool cpu_quota(int& value);

src/hotspot/os/linux/cgroupUtil_linux.cpp

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2024, 2025, Red Hat, Inc.
+ * Copyright (c) 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -25,9 +26,8 @@
 #include "cgroupUtil_linux.hpp"
 #include "os_linux.hpp"
 
-bool CgroupUtil::processor_count(CgroupCpuController* cpu_ctrl, int upper_bound, int& value) {
+bool CgroupUtil::processor_count(CgroupCpuController* cpu_ctrl, int upper_bound, double& value) {
   assert(upper_bound > 0, "upper bound of cpus must be positive");
-  int limit_count = upper_bound;
   int quota = -1;
   int period = -1;
   if (!cpu_ctrl->cpu_quota(quota)) {
@@ -37,20 +37,15 @@ bool CgroupUtil::processor_count(CgroupCpuController* cpu_ctrl, int upper_bound,
     return false;
   }
   int quota_count = 0;
-  int result = upper_bound;
+  double result = upper_bound;
 
-  if (quota > -1 && period > 0) {
-    quota_count = ceilf((float)quota / (float)period);
-    log_trace(os, container)("CPU Quota count based on quota/period: %d", quota_count);
+  if (quota > 0 && period > 0) { // Use quotas
+    double cpu_quota = static_cast<double>(quota) / period;
+    log_trace(os, container)("CPU Quota based on quota/period: %.2f", cpu_quota);
+    result = MIN2(result, cpu_quota);
   }
 
-  // Use quotas
-  if (quota_count != 0) {
-    limit_count = quota_count;
-  }
-
-  result = MIN2(upper_bound, limit_count);
-  log_trace(os, container)("OSContainer::active_processor_count: %d", result);
+  log_trace(os, container)("OSContainer::active_processor_count: %.2f", result);
   value = result;
   return true;
 }
@@ -73,11 +68,11 @@ physical_memory_size_type CgroupUtil::get_updated_mem_limit(CgroupMemoryControll
 
 // Get an updated cpu limit. The return value is strictly less than or equal to the
 // passed in 'lowest' value.
-int CgroupUtil::get_updated_cpu_limit(CgroupCpuController* cpu,
+double CgroupUtil::get_updated_cpu_limit(CgroupCpuController* cpu,
                                      int lowest,
                                      int upper_bound) {
   assert(lowest > 0 && lowest <= upper_bound, "invariant");
-  int cpu_limit_val = -1;
+  double cpu_limit_val = -1;
   if (CgroupUtil::processor_count(cpu, upper_bound, cpu_limit_val) && cpu_limit_val != upper_bound) {
     assert(cpu_limit_val <= upper_bound, "invariant");
     if (lowest > cpu_limit_val) {
@@ -172,7 +167,7 @@ void CgroupUtil::adjust_controller(CgroupCpuController* cpu) {
   assert(cg_path[0] == '/', "cgroup path must start with '/'");
   int host_cpus = os::Linux::active_processor_count();
   int lowest_limit = host_cpus;
-  int cpus = get_updated_cpu_limit(cpu, lowest_limit, host_cpus);
+  double cpus = get_updated_cpu_limit(cpu, lowest_limit, host_cpus);
   int orig_limit = lowest_limit != host_cpus ? lowest_limit : host_cpus;
   char* limit_cg_path = nullptr;
   while ((last_slash = strrchr(cg_path, '/')) != cg_path) {

src/hotspot/os/linux/cgroupUtil_linux.hpp

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2024, Red Hat, Inc.
+ * Copyright (c) 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -31,7 +32,7 @@
 class CgroupUtil: AllStatic {
 
   public:
-    static bool processor_count(CgroupCpuController* cpu, int upper_bound, int& value);
+    static bool processor_count(CgroupCpuController* cpu, int upper_bound, double& value);
     // Given a memory controller, adjust its path to a point in the hierarchy
     // that represents the closest memory limit.
     static void adjust_controller(CgroupMemoryController* m);
@@ -42,9 +43,7 @@ class CgroupUtil: AllStatic {
     static physical_memory_size_type get_updated_mem_limit(CgroupMemoryController* m,
                                                            physical_memory_size_type lowest,
                                                            physical_memory_size_type upper_bound);
-    static int get_updated_cpu_limit(CgroupCpuController* c,
-                                     int lowest,
-                                     int upper_bound);
+    static double get_updated_cpu_limit(CgroupCpuController* c, int lowest, int upper_bound);
 };
 
 #endif // CGROUP_UTIL_LINUX_HPP

src/hotspot/os/linux/cgroupV1Subsystem_linux.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2019, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -328,8 +328,8 @@ CgroupV1Subsystem::CgroupV1Subsystem(CgroupV1Controller* cpuset,
     _pids(pids) {
   CgroupUtil::adjust_controller(memory);
   CgroupUtil::adjust_controller(cpu);
-  _memory = new CachingCgroupController<CgroupMemoryController>(memory);
-  _cpu = new CachingCgroupController<CgroupCpuController>(cpu);
+  _memory = new CachingCgroupController<CgroupMemoryController, physical_memory_size_type>(memory);
+  _cpu = new CachingCgroupController<CgroupCpuController, double>(cpu);
 }
 
 bool CgroupV1Subsystem::is_containerized() {

src/hotspot/os/linux/cgroupV1Subsystem_linux.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2019, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -214,15 +214,15 @@ class CgroupV1Subsystem: public CgroupSubsystem {
     const char * container_type() override {
       return "cgroupv1";
     }
-    CachingCgroupController<CgroupMemoryController>* memory_controller() override { return _memory; }
-    CachingCgroupController<CgroupCpuController>* cpu_controller() override { return _cpu; }
+    CachingCgroupController<CgroupMemoryController, physical_memory_size_type>* memory_controller() override { return _memory; }
+    CachingCgroupController<CgroupCpuController, double>* cpu_controller() override { return _cpu; }
     CgroupCpuacctController* cpuacct_controller() override { return _cpuacct; }
 
   private:
     /* controllers */
-    CachingCgroupController<CgroupMemoryController>* _memory = nullptr;
+    CachingCgroupController<CgroupMemoryController, physical_memory_size_type>* _memory = nullptr;
     CgroupV1Controller* _cpuset = nullptr;
-    CachingCgroupController<CgroupCpuController>* _cpu = nullptr;
+    CachingCgroupController<CgroupCpuController, double>* _cpu = nullptr;
     CgroupV1CpuacctController* _cpuacct = nullptr;
     CgroupV1Controller* _pids = nullptr;
 

src/hotspot/os/linux/cgroupV2Subsystem_linux.cpp

@@ -1,6 +1,6 @@
 /*
  * Copyright (c) 2020, 2025, Red Hat Inc.
- * Copyright (c) 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2025, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -156,8 +156,8 @@ CgroupV2Subsystem::CgroupV2Subsystem(CgroupV2MemoryController * memory,
                                      _unified(unified) {
   CgroupUtil::adjust_controller(memory);
   CgroupUtil::adjust_controller(cpu);
-  _memory = new CachingCgroupController<CgroupMemoryController>(memory);
-  _cpu = new CachingCgroupController<CgroupCpuController>(cpu);
+  _memory = new CachingCgroupController<CgroupMemoryController, physical_memory_size_type>(memory);
+  _cpu = new CachingCgroupController<CgroupCpuController, double>(cpu);
   _cpuacct = cpuacct;
 }
 

src/hotspot/os/linux/cgroupV2Subsystem_linux.hpp

@@ -1,6 +1,6 @@
 /*
  * Copyright (c) 2020, 2024, Red Hat Inc.
- * Copyright (c) 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2025, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -152,8 +152,8 @@ class CgroupV2Subsystem: public CgroupSubsystem {
     /* One unified controller */
     CgroupV2Controller _unified;
     /* Caching wrappers for cpu/memory metrics */
-    CachingCgroupController<CgroupMemoryController>* _memory = nullptr;
-    CachingCgroupController<CgroupCpuController>* _cpu = nullptr;
+    CachingCgroupController<CgroupMemoryController, physical_memory_size_type>* _memory = nullptr;
+    CachingCgroupController<CgroupCpuController, double>* _cpu = nullptr;
 
     CgroupCpuacctController* _cpuacct = nullptr;
 
@@ -175,8 +175,8 @@ class CgroupV2Subsystem: public CgroupSubsystem {
     const char * container_type() override {
       return "cgroupv2";
     }
-    CachingCgroupController<CgroupMemoryController>* memory_controller() override { return _memory; }
-    CachingCgroupController<CgroupCpuController>* cpu_controller() override { return _cpu; }
+    CachingCgroupController<CgroupMemoryController, physical_memory_size_type>* memory_controller() override { return _memory; }
+    CachingCgroupController<CgroupCpuController, double>* cpu_controller() override { return _cpu; }
     CgroupCpuacctController* cpuacct_controller() override { return _cpuacct; };
 };
 

src/hotspot/os/linux/gc/z/zPhysicalMemoryBacking_linux.cpp

@@ -66,9 +66,6 @@
 #endif
 
 // open(2) flags
-#ifndef O_CLOEXEC
-#define O_CLOEXEC                        02000000
-#endif
 #ifndef O_TMPFILE
 #define O_TMPFILE                        (020000000 | O_DIRECTORY)
 #endif

src/hotspot/os/linux/osContainer_linux.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2017, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -86,8 +86,8 @@ void OSContainer::init() {
     //  2.) On a physical Linux system with a limit enforced by other means (like systemd slice)
     physical_memory_size_type mem_limit_val = value_unlimited;
     (void)memory_limit_in_bytes(mem_limit_val);  // discard error and use default
-    int host_cpus = os::Linux::active_processor_count();
-    int cpus = host_cpus;
+    double host_cpus = os::Linux::active_processor_count();
+    double cpus = host_cpus;
     (void)active_processor_count(cpus);  // discard error and use default
     any_mem_cpu_limit_present = mem_limit_val != value_unlimited || host_cpus != cpus;
     if (any_mem_cpu_limit_present) {
@@ -127,8 +127,7 @@ bool OSContainer::available_memory_in_bytes(physical_memory_size_type& value) {
   return false;
 }
 
-bool OSContainer::available_swap_in_bytes(physical_memory_size_type host_free_swap,
-                                          physical_memory_size_type& value) {
+bool OSContainer::available_swap_in_bytes(physical_memory_size_type& value) {
   physical_memory_size_type mem_limit = 0;
   physical_memory_size_type mem_swap_limit = 0;
   if (memory_limit_in_bytes(mem_limit) &&
@@ -179,8 +178,7 @@ bool OSContainer::available_swap_in_bytes(physical_memory_size_type host_free_sw
     assert(num < 25, "buffer too small");
     mem_limit_buf[num] = '\0';
     log_trace(os,container)("OSContainer::available_swap_in_bytes: container_swap_limit=%s"
-                            " container_mem_limit=%s, host_free_swap: " PHYS_MEM_TYPE_FORMAT,
-                            mem_swap_buf, mem_limit_buf, host_free_swap);
+                            " container_mem_limit=%s", mem_swap_buf, mem_limit_buf);
   }
   return false;
 }
@@ -252,7 +250,7 @@ char * OSContainer::cpu_cpuset_memory_nodes() {
   return cgroup_subsystem->cpu_cpuset_memory_nodes();
 }
 
-bool OSContainer::active_processor_count(int& value) {
+bool OSContainer::active_processor_count(double& value) {
   assert(cgroup_subsystem != nullptr, "cgroup subsystem not available");
   return cgroup_subsystem->active_processor_count(value);
 }
@@ -291,11 +289,13 @@ template<typename T> struct metric_fmt;
 template<> struct metric_fmt<unsigned long long int> { static constexpr const char* fmt = "%llu"; };
 template<> struct metric_fmt<unsigned long int> { static constexpr const char* fmt = "%lu"; };
 template<> struct metric_fmt<int> { static constexpr const char* fmt = "%d"; };
+template<> struct metric_fmt<double> { static constexpr const char* fmt = "%.2f"; };
 template<> struct metric_fmt<const char*> { static constexpr const char* fmt = "%s"; };
 
 template void OSContainer::print_container_metric<unsigned long long int>(outputStream*, const char*, unsigned long long int, const char*);
 template void OSContainer::print_container_metric<unsigned long int>(outputStream*, const char*, unsigned long int, const char*);
 template void OSContainer::print_container_metric<int>(outputStream*, const char*, int, const char*);
+template void OSContainer::print_container_metric<double>(outputStream*, const char*, double, const char*);
 template void OSContainer::print_container_metric<const char*>(outputStream*, const char*, const char*, const char*);
 
 template <typename T>
@@ -304,12 +304,13 @@ void OSContainer::print_container_metric(outputStream* st, const char* metrics,
   constexpr int longest_value = max_length - 11; // Max length - shortest "metric: " string ("cpu_quota: ")
   char value_str[longest_value + 1] = {};
   os::snprintf_checked(value_str, longest_value, metric_fmt<T>::fmt, value);
-  st->print("%s: %*s", metrics, max_length - static_cast<int>(strlen(metrics)) - 2, value_str); // -2 for the ": "
-  if (unit[0] != '\0') {
-    st->print_cr(" %s", unit);
-  } else {
-    st->print_cr("");
-  }
+
+  const int pad_width = max_length - static_cast<int>(strlen(metrics)) - 2; // -2 for the ": "
+  const char* unit_prefix = unit[0] != '\0' ? " " : "";
+
+  char line[128] = {};
+  os::snprintf_checked(line, sizeof(line), "%s: %*s%s%s", metrics, pad_width, value_str, unit_prefix, unit);
+  st->print_cr("%s", line);
 }
 
 void OSContainer::print_container_helper(outputStream* st, MetricResult& res, const char* metrics) {

src/hotspot/os/linux/osContainer_linux.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2017, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -72,8 +72,7 @@ class OSContainer: AllStatic {
   static const char * container_type();
 
   static bool available_memory_in_bytes(physical_memory_size_type& value);
-  static bool available_swap_in_bytes(physical_memory_size_type host_free_swap,
-                                      physical_memory_size_type& value);
+  static bool available_swap_in_bytes(physical_memory_size_type& value);
   static bool memory_limit_in_bytes(physical_memory_size_type& value);
   static bool memory_and_swap_limit_in_bytes(physical_memory_size_type& value);
   static bool memory_and_swap_usage_in_bytes(physical_memory_size_type& value);
@@ -84,7 +83,7 @@ class OSContainer: AllStatic {
   static bool rss_usage_in_bytes(physical_memory_size_type& value);
   static bool cache_usage_in_bytes(physical_memory_size_type& value);
 
-  static bool active_processor_count(int& value);
+  static bool active_processor_count(double& value);
 
   static char * cpu_cpuset_cpus();
   static char * cpu_cpuset_memory_nodes();

src/hotspot/os/linux/os_linux.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2015, 2024 SAP SE. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -27,6 +27,7 @@
 #include "code/vtableStubs.hpp"
 #include "compiler/compileBroker.hpp"
 #include "compiler/disassembler.hpp"
+#include "cppstdlib/cstdlib.hpp"
 #include "hugepages.hpp"
 #include "interpreter/interpreter.hpp"
 #include "jvm.h"
@@ -96,7 +97,6 @@
 # include <signal.h>
 # include <stdint.h>
 # include <stdio.h>
-# include <stdlib.h>
 # include <string.h>
 # include <sys/ioctl.h>
 # include <sys/ipc.h>
@@ -211,15 +211,58 @@ static bool suppress_primordial_thread_resolution = false;
 
 // utility functions
 
+bool os::is_containerized() {
+  return OSContainer::is_containerized();
+}
+
+bool os::Container::memory_limit(physical_memory_size_type& value) {
+  physical_memory_size_type result = 0;
+  if (OSContainer::memory_limit_in_bytes(result) && result != value_unlimited) {
+    value = result;
+    return true;
+  }
+  return false;
+}
+
+bool os::Container::memory_soft_limit(physical_memory_size_type& value) {
+  physical_memory_size_type result = 0;
+  if (OSContainer::memory_soft_limit_in_bytes(result) && result != 0 && result != value_unlimited) {
+    value = result;
+    return true;
+  }
+  return false;
+}
+
+bool os::Container::memory_throttle_limit(physical_memory_size_type& value) {
+  physical_memory_size_type result = 0;
+  if (OSContainer::memory_throttle_limit_in_bytes(result) && result != value_unlimited) {
+    value = result;
+    return true;
+  }
+  return false;
+}
+
+bool os::Container::used_memory(physical_memory_size_type& value) {
+  return OSContainer::memory_usage_in_bytes(value);
+}
+
 bool os::available_memory(physical_memory_size_type& value) {
-  if (OSContainer::is_containerized() && OSContainer::available_memory_in_bytes(value)) {
+  if (is_containerized() && Container::available_memory(value)) {
     log_trace(os)("available container memory: " PHYS_MEM_TYPE_FORMAT, value);
     return true;
   }
 
+  return Machine::available_memory(value);
+}
+
+bool os::Machine::available_memory(physical_memory_size_type& value) {
   return Linux::available_memory(value);
 }
 
+bool os::Container::available_memory(physical_memory_size_type& value) {
+  return OSContainer::available_memory_in_bytes(value);
+}
+
 bool os::Linux::available_memory(physical_memory_size_type& value) {
   physical_memory_size_type avail_mem = 0;
 
@@ -251,11 +294,15 @@ bool os::Linux::available_memory(physical_memory_size_type& value) {
 }
 
 bool os::free_memory(physical_memory_size_type& value) {
-  if (OSContainer::is_containerized() && OSContainer::available_memory_in_bytes(value)) {
+  if (is_containerized() && Container::available_memory(value)) {
     log_trace(os)("free container memory: " PHYS_MEM_TYPE_FORMAT, value);
     return true;
   }
 
+  return Machine::free_memory(value);
+}
+
+bool os::Machine::free_memory(physical_memory_size_type& value) {
   return Linux::free_memory(value);
 }
 
@@ -274,21 +321,30 @@ bool os::Linux::free_memory(physical_memory_size_type& value) {
 }
 
 bool os::total_swap_space(physical_memory_size_type& value) {
-  if (OSContainer::is_containerized()) {
-    physical_memory_size_type mem_swap_limit = value_unlimited;
-    physical_memory_size_type memory_limit = value_unlimited;
-    if (OSContainer::memory_and_swap_limit_in_bytes(mem_swap_limit) &&
-        OSContainer::memory_limit_in_bytes(memory_limit)) {
-      if (memory_limit != value_unlimited && mem_swap_limit != value_unlimited &&
-          mem_swap_limit >= memory_limit /* ensure swap is >= 0 */) {
-        value = mem_swap_limit - memory_limit;
-        return true;
-      }
-    }
-  } // fallback to the host swap space if the container returned unlimited
+  if (is_containerized() && Container::total_swap_space(value)) {
+    return true;
+  } // fallback to the host swap space if the container value fails
+  return Machine::total_swap_space(value);
+}
+
+bool os::Machine::total_swap_space(physical_memory_size_type& value) {
   return Linux::host_swap(value);
 }
 
+bool os::Container::total_swap_space(physical_memory_size_type& value) {
+  physical_memory_size_type mem_swap_limit = value_unlimited;
+  physical_memory_size_type memory_limit = value_unlimited;
+  if (OSContainer::memory_and_swap_limit_in_bytes(mem_swap_limit) &&
+      OSContainer::memory_limit_in_bytes(memory_limit)) {
+    if (memory_limit != value_unlimited && mem_swap_limit != value_unlimited &&
+        mem_swap_limit >= memory_limit /* ensure swap is >= 0 */) {
+      value = mem_swap_limit - memory_limit;
+      return true;
+    }
+  }
+  return false;
+}
+
 static bool host_free_swap_f(physical_memory_size_type& value) {
   struct sysinfo si;
   int ret = sysinfo(&si);
@@ -309,32 +365,45 @@ bool os::free_swap_space(physical_memory_size_type& value) {
     return false;
   }
   physical_memory_size_type host_free_swap_val = MIN2(total_swap_space, host_free_swap);
-  if (OSContainer::is_containerized()) {
-    if (OSContainer::available_swap_in_bytes(host_free_swap_val, value)) {
+  if (is_containerized()) {
+    if (Container::free_swap_space(value)) {
       return true;
     }
     // Fall through to use host value
     log_trace(os,container)("os::free_swap_space: containerized value unavailable"
                             " returning host value: " PHYS_MEM_TYPE_FORMAT, host_free_swap_val);
   }
+
   value = host_free_swap_val;
   return true;
 }
 
+bool os::Machine::free_swap_space(physical_memory_size_type& value) {
+  return host_free_swap_f(value);
+}
+
+bool os::Container::free_swap_space(physical_memory_size_type& value) {
+  return OSContainer::available_swap_in_bytes(value);
+}
+
 physical_memory_size_type os::physical_memory() {
-  if (OSContainer::is_containerized()) {
+  if (is_containerized()) {
     physical_memory_size_type mem_limit = value_unlimited;
-    if (OSContainer::memory_limit_in_bytes(mem_limit) && mem_limit != value_unlimited) {
+    if (Container::memory_limit(mem_limit) && mem_limit != value_unlimited) {
       log_trace(os)("total container memory: " PHYS_MEM_TYPE_FORMAT, mem_limit);
       return mem_limit;
     }
   }
 
-  physical_memory_size_type phys_mem = Linux::physical_memory();
+  physical_memory_size_type phys_mem = Machine::physical_memory();
   log_trace(os)("total system memory: " PHYS_MEM_TYPE_FORMAT, phys_mem);
   return phys_mem;
 }
 
+physical_memory_size_type os::Machine::physical_memory() {
+  return Linux::physical_memory();
+}
+
 // Returns the resident set size (RSS) of the process.
 // Falls back to using VmRSS from /proc/self/status if /proc/self/smaps_rollup is unavailable.
 // Note: On kernels with memory cgroups or shared memory, VmRSS may underreport RSS.
@@ -2439,20 +2508,21 @@ bool os::Linux::print_container_info(outputStream* st) {
   OSContainer::print_container_metric(st, "cpu_memory_nodes", p != nullptr ? p : "not supported");
   free(p);
 
-  int i = -1;
-  bool supported = OSContainer::active_processor_count(i);
+  double cpus = -1;
+  bool supported = OSContainer::active_processor_count(cpus);
   if (supported) {
-    assert(i > 0, "must be");
+    assert(cpus > 0, "must be");
     if (ActiveProcessorCount > 0) {
       OSContainer::print_container_metric(st, "active_processor_count", ActiveProcessorCount, "(from -XX:ActiveProcessorCount)");
     } else {
-      OSContainer::print_container_metric(st, "active_processor_count", i);
+      OSContainer::print_container_metric(st, "active_processor_count", cpus);
     }
   } else {
     OSContainer::print_container_metric(st, "active_processor_count", "not supported");
   }
 
 
+  int i = -1;
   supported = OSContainer::cpu_quota(i);
   if (supported && i > 0) {
     OSContainer::print_container_metric(st, "cpu_quota", i);
@@ -4737,15 +4807,26 @@ int os::active_processor_count() {
     return ActiveProcessorCount;
   }
 
-  int active_cpus = -1;
-  if (OSContainer::is_containerized() && OSContainer::active_processor_count(active_cpus)) {
-    log_trace(os)("active_processor_count: determined by OSContainer: %d",
-                   active_cpus);
-  } else {
-    active_cpus = os::Linux::active_processor_count();
+  if (is_containerized()) {
+    double cpu_quota;
+    if (Container::processor_count(cpu_quota)) {
+      int active_cpus = ceilf(cpu_quota); // Round fractional CPU quota up.
+      assert(active_cpus <= Machine::active_processor_count(), "must be");
+      log_trace(os)("active_processor_count: determined by OSContainer: %d",
+                     active_cpus);
+      return active_cpus;
+    }
   }
 
-  return active_cpus;
+  return Machine::active_processor_count();
+}
+
+int os::Machine::active_processor_count() {
+  return os::Linux::active_processor_count();
+}
+
+bool os::Container::processor_count(double& value) {
+  return OSContainer::active_processor_count(value);
 }
 
 static bool should_warn_invalid_processor_id() {
@@ -4878,36 +4959,18 @@ int os::open(const char *path, int oflag, int mode) {
   // All file descriptors that are opened in the Java process and not
   // specifically destined for a subprocess should have the close-on-exec
   // flag set.  If we don't set it, then careless 3rd party native code
-  // might fork and exec without closing all appropriate file descriptors,
-  // and this in turn might:
-  //
-  // - cause end-of-file to fail to be detected on some file
-  //   descriptors, resulting in mysterious hangs, or
-  //
-  // - might cause an fopen in the subprocess to fail on a system
-  //   suffering from bug 1085341.
-  //
-  // (Yes, the default setting of the close-on-exec flag is a Unix
-  // design flaw)
-  //
-  // See:
-  // 1085341: 32-bit stdio routines should support file descriptors >255
-  // 4843136: (process) pipe file descriptor from Runtime.exec not being closed
-  // 6339493: (process) Runtime.exec does not close all file descriptors on Solaris 9
-  //
-  // Modern Linux kernels (after 2.6.23 2007) support O_CLOEXEC with open().
-  // O_CLOEXEC is preferable to using FD_CLOEXEC on an open file descriptor
-  // because it saves a system call and removes a small window where the flag
-  // is unset.  On ancient Linux kernels the O_CLOEXEC flag will be ignored
-  // and we fall back to using FD_CLOEXEC (see below).
-#ifdef O_CLOEXEC
+  // might fork and exec without closing all appropriate file descriptors.
   oflag |= O_CLOEXEC;
-#endif
 
   int fd = ::open(path, oflag, mode);
-  if (fd == -1) return -1;
+  // No further checking is needed if open() returned an error or
+  // access mode is not read only.
+  if (fd == -1 || (oflag & O_ACCMODE) != O_RDONLY) {
+    return fd;
+  }
 
-  //If the open succeeded, the file might still be a directory
+  // If the open succeeded and is read only, the file might be a directory
+  // which the JVM doesn't allow to be read.
   {
     struct stat buf;
     int ret = ::fstat(fd, &buf);
@@ -4925,21 +4988,6 @@ int os::open(const char *path, int oflag, int mode) {
     }
   }
 
-#ifdef FD_CLOEXEC
-  // Validate that the use of the O_CLOEXEC flag on open above worked.
-  // With recent kernels, we will perform this check exactly once.
-  static sig_atomic_t O_CLOEXEC_is_known_to_work = 0;
-  if (!O_CLOEXEC_is_known_to_work) {
-    int flags = ::fcntl(fd, F_GETFD);
-    if (flags != -1) {
-      if ((flags & FD_CLOEXEC) != 0)
-        O_CLOEXEC_is_known_to_work = 1;
-      else
-        ::fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
-    }
-  }
-#endif
-
   return fd;
 }
 

src/hotspot/os/linux/os_perf_linux.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -22,6 +22,7 @@
  *
  */
 
+#include "cppstdlib/cstdlib.hpp"
 #include "jvm.h"
 #include "memory/allocation.inline.hpp"
 #include "os_linux.inline.hpp"
@@ -40,7 +41,6 @@
 #include <pthread.h>
 #include <stdarg.h>
 #include <stdio.h>
-#include <stdlib.h>
 #include <string.h>
 #include <sys/resource.h>
 #include <sys/stat.h>

src/hotspot/os/posix/forbiddenFunctions_posix.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2024, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2024, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -36,15 +36,12 @@
 #include <unistd.h>
 #endif
 
+// POSIX puts _exit in <unistd.h>.
+FORBID_IMPORTED_NORETURN_C_FUNCTION(void _exit(int), /* not noexcept */, "use os::exit")
+
 // If needed, add os::strndup and use that instead.
 FORBID_C_FUNCTION(char* strndup(const char*, size_t), noexcept, "don't use");
 
-// These are unimplementable for Windows, and they aren't useful for a
-// POSIX implementation of NMT either.
-// https://stackoverflow.com/questions/62962839/stdaligned-alloc-missing-from-visual-studio-2019
-FORBID_C_FUNCTION(int posix_memalign(void**, size_t, size_t), noexcept, "don't use");
-FORBID_C_FUNCTION(void* aligned_alloc(size_t, size_t), noexcept, "don't use");
-
 // realpath with a null second argument mallocs a string for the result.
 // With a non-null second argument, there is a risk of buffer overrun.
 PRAGMA_DIAG_PUSH

src/hotspot/os/posix/os_posix.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -23,6 +23,7 @@
  */
 
 #include "classfile/classLoader.hpp"
+#include "cppstdlib/cstdlib.hpp"
 #include "interpreter/interpreter.hpp"
 #include "jvm.h"
 #include "jvmtifiles/jvmti.h"
@@ -457,12 +458,10 @@ char* os::map_memory_to_file(char* base, size_t size, int fd) {
     warning("Failed mmap to file. (%s)", os::strerror(errno));
     return nullptr;
   }
-  if (base != nullptr && addr != base) {
-    if (!os::release_memory(addr, size)) {
-      warning("Could not release memory on unsuccessful file mapping");
-    }
-    return nullptr;
-  }
+
+  // The requested address should be the same as the returned address when using MAP_FIXED
+  // as per POSIX.
+  assert(base == nullptr || addr == base, "base should equal addr when using MAP_FIXED");
   return addr;
 }
 

src/hotspot/os/posix/perfMemory_posix.cpp

@@ -1,6 +1,6 @@
 /*
- * Copyright (c) 2001, 2025, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2012, 2021 SAP SE. All rights reserved.
+ * Copyright (c) 2001, 2026, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2026 SAP SE. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -112,6 +112,10 @@ static void save_memory_to_file(char* addr, size_t size) {
     result = ::close(fd);
     if (result == OS_ERR) {
       warning("Could not close %s: %s\n", destfile, os::strerror(errno));
+    } else {
+      if (!successful_write) {
+        remove(destfile);
+      }
     }
   }
   FREE_C_HEAP_ARRAY(char, destfile);
@@ -946,9 +950,10 @@ static int create_sharedmem_file(const char* dirname, const char* filename, size
     if (result == -1 ) break;
     if (!os::write(fd, &zero_int, 1)) {
       if (errno == ENOSPC) {
-        warning("Insufficient space for shared memory file:\n   %s\nTry using the -Djava.io.tmpdir= option to select an alternate temp location.\n", filename);
+        warning("Insufficient space for shared memory file: %s/%s\n", dirname, filename);
       }
       result = OS_ERR;
+      remove(filename);
       break;
     }
   }

src/hotspot/os/posix/permitForbiddenFunctions_posix.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2024, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2024, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -25,15 +25,20 @@
 #ifndef OS_POSIX_PERMITFORBIDDENFUNCTIONS_POSIX_HPP
 #define OS_POSIX_PERMITFORBIDDENFUNCTIONS_POSIX_HPP
 
+#include "cppstdlib/cstdlib.hpp"
 #include "utilities/compilerWarnings.hpp"
 #include "utilities/globalDefinitions.hpp"
 
+#include <unistd.h>
+
 // Provide wrappers for some functions otherwise forbidden from use in HotSpot.
 // See forbiddenFunctions.hpp for details.
 
 namespace permit_forbidden_function {
 BEGIN_ALLOW_FORBIDDEN_FUNCTIONS
 
+[[noreturn]] inline void _exit(int status) { ::_exit(status); }
+
 // Used by the POSIX implementation of os::realpath.
 inline char* realpath(const char* path, char* resolved_path) {
   return ::realpath(path, resolved_path);

src/hotspot/os/posix/signals_posix.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2020, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -951,6 +951,32 @@ struct enum_sigcode_desc_t {
   const char* s_desc;
 };
 
+#if defined(LINUX)
+// Additional kernel si_code definitions that are only exported by
+// more recent glibc distributions, so we have to hard-code the values.
+#ifndef BUS_MCEERR_AR // glibc 2.17
+#define BUS_MCEERR_AR 4
+#define BUS_MCEERR_AO 5
+#endif
+
+#ifndef SEGV_PKUERR // glibc 2.27
+#define SEGV_PKUERR 4
+#endif
+
+#ifndef SYS_SECCOMP // glibc 2.28
+#define SYS_SECCOMP 1
+#endif
+
+#ifndef TRAP_BRANCH // glibc 2.30
+#define TRAP_BRANCH 3
+#endif
+
+#ifndef TRAP_HWBKPT // not glibc version specific - gdb related
+#define TRAP_HWBKPT 4
+#endif
+
+#endif // LINUX
+
 static bool get_signal_code_description(const siginfo_t* si, enum_sigcode_desc_t* out) {
 
   const struct {
@@ -976,6 +1002,7 @@ static bool get_signal_code_description(const siginfo_t* si, enum_sigcode_desc_t
     { SIGSEGV, SEGV_ACCERR,  "SEGV_ACCERR",  "Invalid permissions for mapped object." },
 #if defined(LINUX)
     { SIGSEGV, SEGV_BNDERR,  "SEGV_BNDERR",  "Failed address bound checks." },
+    { SIGSEGV, SEGV_PKUERR,  "SEGV_PKUERR",  "Protection key checking failure." },
 #endif
 #if defined(AIX)
     // no explanation found what keyerr would be
@@ -984,8 +1011,18 @@ static bool get_signal_code_description(const siginfo_t* si, enum_sigcode_desc_t
     { SIGBUS,  BUS_ADRALN,   "BUS_ADRALN",   "Invalid address alignment." },
     { SIGBUS,  BUS_ADRERR,   "BUS_ADRERR",   "Nonexistent physical address." },
     { SIGBUS,  BUS_OBJERR,   "BUS_OBJERR",   "Object-specific hardware error." },
+#if defined(LINUX)
+    { SIGBUS,  BUS_MCEERR_AR,"BUS_MCEERR_AR","Hardware memory error consumed on a machine check: action required." },
+    { SIGBUS,  BUS_MCEERR_AO,"BUS_MCEERR_AO","Hardware memory error detected in process but not consumed: action optional." },
+
+    { SIGSYS,  SYS_SECCOMP,  "SYS_SECCOMP",  "Secure computing (seccomp) filter failure." },
+#endif
     { SIGTRAP, TRAP_BRKPT,   "TRAP_BRKPT",   "Process breakpoint." },
     { SIGTRAP, TRAP_TRACE,   "TRAP_TRACE",   "Process trace trap." },
+#if defined(LINUX)
+    { SIGTRAP, TRAP_BRANCH,  "TRAP_BRANCH",  "Process taken branch trap." },
+    { SIGTRAP, TRAP_HWBKPT,  "TRAP_HWBKPT",  "Hardware breakpoint/watchpoint." },
+#endif
     { SIGCHLD, CLD_EXITED,   "CLD_EXITED",   "Child has exited." },
     { SIGCHLD, CLD_KILLED,   "CLD_KILLED",   "Child has terminated abnormally and did not create a core file." },
     { SIGCHLD, CLD_DUMPED,   "CLD_DUMPED",   "Child has terminated abnormally and created a core file." },
@@ -993,6 +1030,7 @@ static bool get_signal_code_description(const siginfo_t* si, enum_sigcode_desc_t
     { SIGCHLD, CLD_STOPPED,  "CLD_STOPPED",  "Child has stopped." },
     { SIGCHLD, CLD_CONTINUED,"CLD_CONTINUED","Stopped child has continued." },
 #ifdef SIGPOLL
+    { SIGPOLL, POLL_IN,      "POLL_IN",      "Data input available." },
     { SIGPOLL, POLL_OUT,     "POLL_OUT",     "Output buffers available." },
     { SIGPOLL, POLL_MSG,     "POLL_MSG",     "Input message available." },
     { SIGPOLL, POLL_ERR,     "POLL_ERR",     "I/O error." },

src/hotspot/os/windows/os_windows.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -30,6 +30,7 @@
 #include "code/vtableStubs.hpp"
 #include "compiler/compileBroker.hpp"
 #include "compiler/disassembler.hpp"
+#include "cppstdlib/cstdlib.hpp"
 #include "interpreter/interpreter.hpp"
 #include "jvm.h"
 #include "jvmtifiles/jvmti.h"
@@ -838,10 +839,18 @@ bool os::available_memory(physical_memory_size_type& value) {
   return win32::available_memory(value);
 }
 
+bool os::Machine::available_memory(physical_memory_size_type& value) {
+  return win32::available_memory(value);
+}
+
 bool os::free_memory(physical_memory_size_type& value) {
   return win32::available_memory(value);
 }
 
+bool os::Machine::free_memory(physical_memory_size_type& value) {
+  return win32::available_memory(value);
+}
+
 bool os::win32::available_memory(physical_memory_size_type& value) {
   // Use GlobalMemoryStatusEx() because GlobalMemoryStatus() may return incorrect
   // value if total memory is larger than 4GB
@@ -857,7 +866,11 @@ bool os::win32::available_memory(physical_memory_size_type& value) {
   }
 }
 
-bool os::total_swap_space(physical_memory_size_type& value) {
+bool os::total_swap_space(physical_memory_size_type& value)  {
+  return Machine::total_swap_space(value);
+}
+
+bool os::Machine::total_swap_space(physical_memory_size_type& value) {
   MEMORYSTATUSEX ms;
   ms.dwLength = sizeof(ms);
   BOOL res = GlobalMemoryStatusEx(&ms);
@@ -871,6 +884,10 @@ bool os::total_swap_space(physical_memory_size_type& value) {
 }
 
 bool os::free_swap_space(physical_memory_size_type& value) {
+  return Machine::free_swap_space(value);
+}
+
+bool os::Machine::free_swap_space(physical_memory_size_type& value) {
   MEMORYSTATUSEX ms;
   ms.dwLength = sizeof(ms);
   BOOL res = GlobalMemoryStatusEx(&ms);
@@ -887,6 +904,10 @@ physical_memory_size_type os::physical_memory() {
   return win32::physical_memory();
 }
 
+physical_memory_size_type os::Machine::physical_memory() {
+  return win32::physical_memory();
+}
+
 size_t os::rss() {
   size_t rss = 0;
   PROCESS_MEMORY_COUNTERS_EX pmex;
@@ -910,6 +931,10 @@ int os::active_processor_count() {
     return ActiveProcessorCount;
   }
 
+  return Machine::active_processor_count();
+}
+
+int os::Machine::active_processor_count() {
   bool schedules_all_processor_groups = win32::is_windows_11_or_greater() || win32::is_windows_server_2022_or_greater();
   if (UseAllWindowsProcessorGroups && !schedules_all_processor_groups && !win32::processor_group_warning_displayed()) {
     win32::set_processor_group_warning_displayed(true);

src/hotspot/os/windows/permitForbiddenFunctions_windows.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2024, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2024, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -25,6 +25,7 @@
 #ifndef OS_WINDOWS_PERMITFORBIDDENFUNCTIONS_WINDOWS_HPP
 #define OS_WINDOWS_PERMITFORBIDDENFUNCTIONS_WINDOWS_HPP
 
+#include "cppstdlib/cstdlib.hpp"
 #include "utilities/compilerWarnings.hpp"
 #include "utilities/globalDefinitions.hpp"
 
@@ -34,6 +35,8 @@
 namespace permit_forbidden_function {
 BEGIN_ALLOW_FORBIDDEN_FUNCTIONS
 
+[[noreturn]] inline void _exit(int status) { ::_exit(status); }
+
 // Used by the Windows implementation of os::realpath.
 inline char* _fullpath(char* absPath, const char* relPath, size_t maxLength) {
   return ::_fullpath(absPath, relPath, maxLength);

src/hotspot/os/windows/vmError_windows.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -24,6 +24,7 @@
 
 #include "cds/aotMetaspace.hpp"
 #include "cds/cdsConfig.hpp"
+#include "cppstdlib/cstdlib.hpp"
 #include "runtime/arguments.hpp"
 #include "runtime/javaThread.hpp"
 #include "runtime/os.hpp"

src/hotspot/os_cpu/aix_ppc/prefetch_aix_ppc.inline.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2012, 2013 SAP SE. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -26,8 +26,7 @@
 #ifndef OS_CPU_AIX_PPC_PREFETCH_AIX_PPC_INLINE_HPP
 #define OS_CPU_AIX_PPC_PREFETCH_AIX_PPC_INLINE_HPP
 
-#include "runtime/prefetch.hpp"
-
+// Included in runtime/prefetch.inline.hpp
 
 inline void Prefetch::read(const void *loc, intx interval) {
 #if !defined(USE_XLC_BUILTINS)

src/hotspot/os_cpu/bsd_aarch64/os_bsd_aarch64.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2014, Red Hat Inc. All rights reserved.
  * Copyright (c) 2021, Azul Systems, Inc. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
@@ -29,6 +29,7 @@
 #include "classfile/vmSymbols.hpp"
 #include "code/codeCache.hpp"
 #include "code/vtableStubs.hpp"
+#include "cppstdlib/cstdlib.hpp"
 #include "interpreter/interpreter.hpp"
 #include "jvm.h"
 #include "logging/log.hpp"
@@ -63,7 +64,6 @@
 # include <signal.h>
 # include <errno.h>
 # include <dlfcn.h>
-# include <stdlib.h>
 # include <stdio.h>
 # include <unistd.h>
 # include <sys/resource.h>

src/hotspot/os_cpu/bsd_aarch64/prefetch_bsd_aarch64.inline.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2014, Red Hat Inc. All rights reserved.
  * Copyright (c) 2021, Azul Systems, Inc. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
@@ -27,8 +27,7 @@
 #ifndef OS_CPU_BSD_AARCH64_PREFETCH_BSD_AARCH64_INLINE_HPP
 #define OS_CPU_BSD_AARCH64_PREFETCH_BSD_AARCH64_INLINE_HPP
 
-#include "runtime/prefetch.hpp"
-
+// Included in runtime/prefetch.inline.hpp
 
 inline void Prefetch::read (const void *loc, intx interval) {
   if (interval >= 0)

src/hotspot/os_cpu/bsd_x86/os_bsd_x86.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -26,6 +26,7 @@
 #include "classfile/vmSymbols.hpp"
 #include "code/codeCache.hpp"
 #include "code/vtableStubs.hpp"
+#include "cppstdlib/cstdlib.hpp"
 #include "interpreter/interpreter.hpp"
 #include "jvm.h"
 #include "logging/log.hpp"
@@ -58,7 +59,6 @@
 # include <signal.h>
 # include <errno.h>
 # include <dlfcn.h>
-# include <stdlib.h>
 # include <stdio.h>
 # include <unistd.h>
 # include <sys/resource.h>

src/hotspot/os_cpu/bsd_x86/prefetch_bsd_x86.inline.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -25,8 +25,7 @@
 #ifndef OS_CPU_BSD_X86_PREFETCH_BSD_X86_INLINE_HPP
 #define OS_CPU_BSD_X86_PREFETCH_BSD_X86_INLINE_HPP
 
-#include "runtime/prefetch.hpp"
-
+// Included in runtime/prefetch.inline.hpp
 
 inline void Prefetch::read (const void *loc, intx interval) {
   __asm__ ("prefetcht0 (%0,%1,1)" : : "r" (loc), "r" (interval));

src/hotspot/os_cpu/bsd_zero/prefetch_bsd_zero.inline.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright 2007, 2008 Red Hat, Inc.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -26,7 +26,7 @@
 #ifndef OS_CPU_BSD_ZERO_PREFETCH_BSD_ZERO_INLINE_HPP
 #define OS_CPU_BSD_ZERO_PREFETCH_BSD_ZERO_INLINE_HPP
 
-#include "runtime/prefetch.hpp"
+// Included in runtime/prefetch.inline.hpp
 
 inline void Prefetch::read(const void* loc, intx interval) {
 }

src/hotspot/os_cpu/linux_aarch64/os_linux_aarch64.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2014, Red Hat Inc. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -28,6 +28,7 @@
 #include "code/codeCache.hpp"
 #include "code/vtableStubs.hpp"
 #include "code/nativeInst.hpp"
+#include "cppstdlib/cstdlib.hpp"
 #include "interpreter/interpreter.hpp"
 #include "jvm.h"
 #include "memory/allocation.inline.hpp"
@@ -59,7 +60,6 @@
 # include <signal.h>
 # include <errno.h>
 # include <dlfcn.h>
-# include <stdlib.h>
 # include <stdio.h>
 # include <unistd.h>
 # include <sys/resource.h>

src/hotspot/os_cpu/linux_aarch64/prefetch_linux_aarch64.inline.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2014, Red Hat Inc. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -26,8 +26,7 @@
 #ifndef OS_CPU_LINUX_AARCH64_PREFETCH_LINUX_AARCH64_INLINE_HPP
 #define OS_CPU_LINUX_AARCH64_PREFETCH_LINUX_AARCH64_INLINE_HPP
 
-#include "runtime/prefetch.hpp"
-
+// Included in runtime/prefetch.inline.hpp
 
 inline void Prefetch::read (const void *loc, intx interval) {
   if (interval >= 0)

src/hotspot/os_cpu/linux_arm/os_linux_arm.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2008, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2008, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -25,6 +25,7 @@
 #include "asm/assembler.inline.hpp"
 #include "classfile/vmSymbols.hpp"
 #include "code/vtableStubs.hpp"
+#include "cppstdlib/cstdlib.hpp"
 #include "interpreter/interpreter.hpp"
 #include "jvm.h"
 #include "memory/allocation.inline.hpp"
@@ -57,7 +58,6 @@
 # include <signal.h>
 # include <errno.h>
 # include <dlfcn.h>
-# include <stdlib.h>
 # include <stdio.h>
 # include <unistd.h>
 # include <sys/resource.h>

src/hotspot/os_cpu/linux_arm/prefetch_linux_arm.inline.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2008, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2008, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -25,7 +25,7 @@
 #ifndef OS_CPU_LINUX_ARM_PREFETCH_LINUX_ARM_INLINE_HPP
 #define OS_CPU_LINUX_ARM_PREFETCH_LINUX_ARM_INLINE_HPP
 
-#include "runtime/prefetch.hpp"
+// Included in runtime/prefetch.inline.hpp
 
 inline void Prefetch::read (const void *loc, intx interval) {
 #if defined(__ARM_ARCH_7A__) || defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_5TE__)

src/hotspot/os_cpu/linux_ppc/os_linux_ppc.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2012, 2025 SAP SE. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -28,6 +28,7 @@
 #include "classfile/vmSymbols.hpp"
 #include "code/codeCache.hpp"
 #include "code/vtableStubs.hpp"
+#include "cppstdlib/cstdlib.hpp"
 #include "interpreter/interpreter.hpp"
 #include "jvm.h"
 #include "memory/allocation.inline.hpp"
@@ -62,7 +63,6 @@
 # include <signal.h>
 # include <errno.h>
 # include <dlfcn.h>
-# include <stdlib.h>
 # include <stdio.h>
 # include <unistd.h>
 # include <sys/resource.h>

src/hotspot/os_cpu/linux_ppc/prefetch_linux_ppc.inline.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2012, 2013 SAP SE. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -26,8 +26,7 @@
 #ifndef OS_CPU_LINUX_PPC_PREFETCH_LINUX_PPC_INLINE_HPP
 #define OS_CPU_LINUX_PPC_PREFETCH_LINUX_PPC_INLINE_HPP
 
-#include "runtime/prefetch.hpp"
-
+// Included in runtime/prefetch.inline.hpp
 
 inline void Prefetch::read(const void *loc, intx interval) {
   __asm__ __volatile__ (

src/hotspot/os_cpu/linux_riscv/os_linux_riscv.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2020, 2022, Huawei Technologies Co., Ltd. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -28,6 +28,7 @@
 #include "code/codeCache.hpp"
 #include "code/nativeInst.hpp"
 #include "code/vtableStubs.hpp"
+#include "cppstdlib/cstdlib.hpp"
 #include "interpreter/interpreter.hpp"
 #include "jvm.h"
 #include "memory/allocation.inline.hpp"
@@ -61,7 +62,6 @@
 # include <pthread.h>
 # include <signal.h>
 # include <stdio.h>
-# include <stdlib.h>
 # include <sys/mman.h>
 # include <sys/resource.h>
 # include <sys/socket.h>

src/hotspot/os_cpu/linux_riscv/prefetch_linux_riscv.inline.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2019, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2020, 2021, Huawei Technologies Co., Ltd. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -26,7 +26,7 @@
 #ifndef OS_CPU_LINUX_RISCV_VM_PREFETCH_LINUX_RISCV_INLINE_HPP
 #define OS_CPU_LINUX_RISCV_VM_PREFETCH_LINUX_RISCV_INLINE_HPP
 
-#include "runtime/prefetch.hpp"
+// Included in runtime/prefetch.inline.hpp
 
 inline void Prefetch::read (const void *loc, intx interval) {
   if (interval >= 0 && UseZicbop) {

src/hotspot/os_cpu/linux_s390/os_linux_s390.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2016, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2016, 2024 SAP SE. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -30,6 +30,7 @@
 #include "code/nativeInst.hpp"
 #include "code/vtableStubs.hpp"
 #include "compiler/disassembler.hpp"
+#include "cppstdlib/cstdlib.hpp"
 #include "interpreter/interpreter.hpp"
 #include "jvm.h"
 #include "memory/allocation.inline.hpp"
@@ -62,7 +63,6 @@
 # include <signal.h>
 # include <errno.h>
 # include <dlfcn.h>
-# include <stdlib.h>
 # include <stdio.h>
 # include <unistd.h>
 # include <sys/resource.h>

src/hotspot/os_cpu/linux_s390/prefetch_linux_s390.inline.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2016, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2016 SAP SE. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -26,7 +26,7 @@
 #ifndef OS_CPU_LINUX_S390_PREFETCH_LINUX_S390_INLINE_HPP
 #define OS_CPU_LINUX_S390_PREFETCH_LINUX_S390_INLINE_HPP
 
-#include "runtime/prefetch.hpp"
+// Included in runtime/prefetch.inline.hpp
 
 inline void Prefetch::read(const void* loc, intx interval) {
   // No prefetch instructions on z/Architecture -> implement trivially.

src/hotspot/os_cpu/linux_x86/os_linux_x86.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1999, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -26,6 +26,7 @@
 #include "classfile/vmSymbols.hpp"
 #include "code/codeCache.hpp"
 #include "code/vtableStubs.hpp"
+#include "cppstdlib/cstdlib.hpp"
 #include "interpreter/interpreter.hpp"
 #include "jvm.h"
 #include "logging/log.hpp"
@@ -59,7 +60,6 @@
 # include <signal.h>
 # include <errno.h>
 # include <dlfcn.h>
-# include <stdlib.h>
 # include <stdio.h>
 # include <unistd.h>
 # include <sys/resource.h>

src/hotspot/os_cpu/linux_x86/prefetch_linux_x86.inline.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -25,8 +25,7 @@
 #ifndef OS_CPU_LINUX_X86_PREFETCH_LINUX_X86_INLINE_HPP
 #define OS_CPU_LINUX_X86_PREFETCH_LINUX_X86_INLINE_HPP
 
-#include "runtime/prefetch.hpp"
-
+// Included in runtime/prefetch.inline.hpp
 
 inline void Prefetch::read (const void *loc, intx interval) {
   __asm__ ("prefetcht0 (%0,%1,1)" : : "r" (loc), "r" (interval));

src/hotspot/os_cpu/linux_zero/prefetch_linux_zero.inline.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2026, Oracle and/or its affiliates. All rights reserved.
  * Copyright 2007, 2008 Red Hat, Inc.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
@@ -26,7 +26,7 @@
 #ifndef OS_CPU_LINUX_ZERO_PREFETCH_LINUX_ZERO_INLINE_HPP
 #define OS_CPU_LINUX_ZERO_PREFETCH_LINUX_ZERO_INLINE_HPP
 
-#include "runtime/prefetch.hpp"
+// Included in runtime/prefetch.inline.hpp
 
 inline void Prefetch::read(const void* loc, intx interval) {
 }

src/hotspot/os_cpu/windows_aarch64/os_windows_aarch64.cpp

@@ -1,6 +1,6 @@
 /*
  * Copyright (c) 2020, Microsoft Corporation. All rights reserved.
- * Copyright (c) 2022, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2022, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -28,6 +28,7 @@
 #include "code/codeCache.hpp"
 #include "code/vtableStubs.hpp"
 #include "code/nativeInst.hpp"
+#include "cppstdlib/cstdlib.hpp"
 #include "interpreter/interpreter.hpp"
 #include "jvm.h"
 #include "memory/allocation.inline.hpp"
@@ -54,7 +55,6 @@
 # include <sys/types.h>
 # include <signal.h>
 # include <errno.h>
-# include <stdlib.h>
 # include <stdio.h>
 # include <intrin.h>
 

src/hotspot/os_cpu/windows_aarch64/prefetch_windows_aarch64.inline.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, Microsoft Corporation. All rights reserved.
+ * Copyright (c) 2020, 2026, Microsoft Corporation. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -25,8 +25,7 @@
 #ifndef OS_CPU_WINDOWS_AARCH64_PREFETCH_WINDOWS_AARCH64_INLINE_HPP
 #define OS_CPU_WINDOWS_AARCH64_PREFETCH_WINDOWS_AARCH64_INLINE_HPP
 
-#include "runtime/prefetch.hpp"
-
+// Included in runtime/prefetch.inline.hpp
 
 inline void Prefetch::read (const void *loc, intx interval) {
 }

src/hotspot/os_cpu/windows_x86/prefetch_windows_x86.inline.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2003, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -25,7 +25,7 @@
 #ifndef OS_CPU_WINDOWS_X86_PREFETCH_WINDOWS_X86_INLINE_HPP
 #define OS_CPU_WINDOWS_X86_PREFETCH_WINDOWS_X86_INLINE_HPP
 
-#include "runtime/prefetch.hpp"
+// Included in runtime/prefetch.inline.hpp
 
 inline void Prefetch::read (const void *loc, intx interval) {}
 inline void Prefetch::write(void *loc, intx interval) {}

src/hotspot/share/cds/aotConstantPoolResolver.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2022, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2022, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -116,6 +116,10 @@ bool AOTConstantPoolResolver::is_class_resolution_deterministic(InstanceKlass* c
       return false;
     }
   } else if (resolved_class->is_objArray_klass()) {
+    if (CDSConfig::is_dumping_dynamic_archive()) {
+      // This is difficult to handle. See JDK-8374639
+      return false;
+    }
     Klass* elem = ObjArrayKlass::cast(resolved_class)->bottom_klass();
     if (elem->is_instance_klass()) {
       return is_class_resolution_deterministic(cp_holder, InstanceKlass::cast(elem));

src/hotspot/share/cds/aotGrowableArray.cpp

@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2026, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#include "cds/aotGrowableArray.hpp"
+#include "cds/aotMetaspace.hpp"
+#include "memory/allocation.inline.hpp"
+#include "utilities/growableArray.hpp"
+
+void AOTGrowableArrayHelper::deallocate(void* mem) {
+  if (!AOTMetaspace::in_aot_cache(mem)) {
+    GrowableArrayCHeapAllocator::deallocate(mem);
+  }
+}

src/hotspot/share/cds/aotGrowableArray.hpp

@@ -0,0 +1,76 @@
+/*
+ * Copyright (c) 2026, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#ifndef SHARE_AOT_AOTGROWABLEARRAY_HPP
+#define SHARE_AOT_AOTGROWABLEARRAY_HPP
+
+#include <memory/metaspaceClosureType.hpp>
+#include <utilities/growableArray.hpp>
+
+class AOTGrowableArrayHelper {
+public:
+  static void deallocate(void* mem);
+};
+
+// An AOTGrowableArray<T> provides the same functionality as a GrowableArray<T> that
+// uses the C heap allocator. In addition, AOTGrowableArray<T> can be iterated with
+// MetaspaceClosure. This type should be used for growable arrays that need to be
+// stored in the AOT cache. See ModuleEntry::_reads for an example.
+template <typename E>
+class AOTGrowableArray : public GrowableArrayWithAllocator<E, AOTGrowableArray<E>> {
+  friend class VMStructs;
+  friend class GrowableArrayWithAllocator<E, AOTGrowableArray>;
+
+  static E* allocate(int max, MemTag mem_tag) {
+    return (E*)GrowableArrayCHeapAllocator::allocate(max, sizeof(E), mem_tag);
+  }
+
+  E* allocate() {
+    return allocate(this->_capacity, mtClass);
+  }
+
+  void deallocate(E* mem) {
+#if INCLUDE_CDS
+    AOTGrowableArrayHelper::deallocate(mem);
+#else
+    GrowableArrayCHeapAllocator::deallocate(mem);
+#endif
+  }
+
+public:
+  AOTGrowableArray(int initial_capacity, MemTag mem_tag) :
+      GrowableArrayWithAllocator<E, AOTGrowableArray>(
+          allocate(initial_capacity, mem_tag),
+          initial_capacity) {}
+
+  AOTGrowableArray() : AOTGrowableArray(0, mtClassShared) {}
+
+  // methods required by MetaspaceClosure
+  void metaspace_pointers_do(MetaspaceClosure* it);
+  int size_in_heapwords() const { return (int)heap_word_size(sizeof(*this)); }
+  MetaspaceClosureType type() const { return MetaspaceClosureType::GrowableArrayType; }
+  static bool is_read_only_by_default() { return false; }
+};
+
+#endif // SHARE_AOT_AOTGROWABLEARRAY_HPP

src/hotspot/share/cds/aotGrowableArray.inline.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -22,17 +22,16 @@
  *
  */
 
-#ifndef SHARE_GC_G1_G1CONCURRENTMARKOBJARRAYPROCESSOR_INLINE_HPP
-#define SHARE_GC_G1_G1CONCURRENTMARKOBJARRAYPROCESSOR_INLINE_HPP
+#ifndef SHARE_CDS_AOTGROWABLEARRAY_INLINE_HPP
+#define SHARE_CDS_AOTGROWABLEARRAY_INLINE_HPP
 
-#include "gc/g1/g1ConcurrentMarkObjArrayProcessor.hpp"
+#include "cds/aotGrowableArray.hpp"
 
-#include "gc/shared/gc_globals.hpp"
-#include "oops/oop.inline.hpp"
-#include "oops/oopsHierarchy.hpp"
+#include "memory/metaspaceClosure.hpp"
 
-inline bool G1CMObjArrayProcessor::should_be_sliced(oop obj) {
-  return obj->is_objArray() && ((objArrayOop)obj)->size() >= 2 * ObjArrayMarkingStride;
+template <typename E>
+void AOTGrowableArray<E>::metaspace_pointers_do(MetaspaceClosure* it) {
+  it->push_c_array(AOTGrowableArray<E>::data_addr(), AOTGrowableArray<E>::capacity());
 }
 
-#endif // SHARE_GC_G1_G1CONCURRENTMARKOBJARRAYPROCESSOR_INLINE_HPP
+#endif // SHARE_CDS_AOTGROWABLEARRAY_INLINE_HPP

src/hotspot/share/cds/aotMapLogger.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2025, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -29,6 +29,8 @@
 #include "cds/aotStreamedHeapWriter.hpp"
 #include "cds/cdsConfig.hpp"
 #include "cds/filemap.hpp"
+#include "classfile/moduleEntry.hpp"
+#include "classfile/packageEntry.hpp"
 #include "classfile/systemDictionaryShared.hpp"
 #include "classfile/vmClasses.hpp"
 #include "logging/log.hpp"
@@ -141,7 +143,7 @@ public:
       info._buffered_addr = ref->obj();
       info._requested_addr = ref->obj();
       info._bytes = ref->size() * BytesPerWord;
-      info._type = ref->msotype();
+      info._type = ref->type();
       _objs.append(info);
     }
 
@@ -214,7 +216,7 @@ void AOTMapLogger::dumptime_log_metaspace_region(const char* name, DumpRegion* r
       info._buffered_addr = src_info->buffered_addr();
       info._requested_addr = info._buffered_addr + _buffer_to_requested_delta;
       info._bytes = src_info->size_in_bytes();
-      info._type = src_info->msotype();
+      info._type = src_info->type();
       objs.append(info);
     }
 
@@ -332,43 +334,52 @@ void AOTMapLogger::log_metaspace_objects_impl(address region_base, address regio
     address buffered_addr = info._buffered_addr;
     address requested_addr = info._requested_addr;
     int bytes = info._bytes;
-    MetaspaceObj::Type type = info._type;
-    const char* type_name = MetaspaceObj::type_name(type);
+    MetaspaceClosureType type = info._type;
+    const char* type_name = MetaspaceClosure::type_name(type);
 
     log_as_hex(last_obj_base, buffered_addr, last_obj_base + _buffer_to_requested_delta);
 
     switch (type) {
-    case MetaspaceObj::ClassType:
+    case MetaspaceClosureType::ClassType:
       log_klass((Klass*)src, requested_addr, type_name, bytes, current);
       break;
-    case MetaspaceObj::ConstantPoolType:
+    case MetaspaceClosureType::ConstantPoolType:
       log_constant_pool((ConstantPool*)src, requested_addr, type_name, bytes, current);
       break;
-    case MetaspaceObj::ConstantPoolCacheType:
+    case MetaspaceClosureType::ConstantPoolCacheType:
       log_constant_pool_cache((ConstantPoolCache*)src, requested_addr, type_name, bytes, current);
       break;
-    case MetaspaceObj::ConstMethodType:
+    case MetaspaceClosureType::ConstMethodType:
       log_const_method((ConstMethod*)src, requested_addr, type_name, bytes, current);
       break;
-    case MetaspaceObj::MethodType:
+    case MetaspaceClosureType::MethodType:
       log_method((Method*)src, requested_addr, type_name, bytes, current);
       break;
-    case MetaspaceObj::MethodCountersType:
+    case MetaspaceClosureType::MethodCountersType:
       log_method_counters((MethodCounters*)src, requested_addr, type_name, bytes, current);
       break;
-    case MetaspaceObj::MethodDataType:
+    case MetaspaceClosureType::MethodDataType:
       log_method_data((MethodData*)src, requested_addr, type_name, bytes, current);
       break;
-    case MetaspaceObj::SymbolType:
+    case MetaspaceClosureType::ModuleEntryType:
+      log_module_entry((ModuleEntry*)src, requested_addr, type_name, bytes, current);
+      break;
+    case MetaspaceClosureType::PackageEntryType:
+      log_package_entry((PackageEntry*)src, requested_addr, type_name, bytes, current);
+      break;
+    case MetaspaceClosureType::GrowableArrayType:
+      log_growable_array((GrowableArrayBase*)src, requested_addr, type_name, bytes, current);
+      break;
+    case MetaspaceClosureType::SymbolType:
       log_symbol((Symbol*)src, requested_addr, type_name, bytes, current);
       break;
-    case MetaspaceObj::KlassTrainingDataType:
+    case MetaspaceClosureType::KlassTrainingDataType:
       log_klass_training_data((KlassTrainingData*)src, requested_addr, type_name, bytes, current);
       break;
-    case MetaspaceObj::MethodTrainingDataType:
+    case MetaspaceClosureType::MethodTrainingDataType:
       log_method_training_data((MethodTrainingData*)src, requested_addr, type_name, bytes, current);
       break;
-    case MetaspaceObj::CompileTrainingDataType:
+    case MetaspaceClosureType::CompileTrainingDataType:
       log_compile_training_data((CompileTrainingData*)src, requested_addr, type_name, bytes, current);
       break;
     default:
@@ -421,6 +432,27 @@ void AOTMapLogger::log_method_data(MethodData* md, address requested_addr, const
   log_debug(aot, map)(_LOG_PREFIX " %s", p2i(requested_addr), type_name, bytes,  md->method()->external_name());
 }
 
+void AOTMapLogger::log_module_entry(ModuleEntry* mod, address requested_addr, const char* type_name,
+                                   int bytes, Thread* current) {
+  ResourceMark rm(current);
+  log_debug(aot, map)(_LOG_PREFIX " %s", p2i(requested_addr), type_name, bytes,
+                      mod->name_as_C_string());
+}
+
+void AOTMapLogger::log_package_entry(PackageEntry* pkg, address requested_addr, const char* type_name,
+                                   int bytes, Thread* current) {
+  ResourceMark rm(current);
+  log_debug(aot, map)(_LOG_PREFIX " %s - %s", p2i(requested_addr), type_name, bytes,
+                      pkg->module()->name_as_C_string(), pkg->name_as_C_string());
+}
+
+void AOTMapLogger::log_growable_array(GrowableArrayBase* arr, address requested_addr, const char* type_name,
+                                      int bytes, Thread* current) {
+  ResourceMark rm(current);
+  log_debug(aot, map)(_LOG_PREFIX " %d (%d)", p2i(requested_addr), type_name, bytes,
+                      arr->length(), arr->capacity());
+}
+
 void AOTMapLogger::log_klass(Klass* k, address requested_addr, const char* type_name,
                              int bytes, Thread* current) {
   ResourceMark rm(current);

src/hotspot/share/cds/aotMapLogger.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2025, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -28,6 +28,7 @@
 #include "cds/archiveBuilder.hpp"
 #include "memory/allocation.hpp"
 #include "memory/allStatic.hpp"
+#include "memory/metaspaceClosureType.hpp"
 #include "oops/oopsHierarchy.hpp"
 #include "utilities/globalDefinitions.hpp"
 #include "utilities/growableArray.hpp"
@@ -37,9 +38,13 @@ class ArchiveStreamedHeapInfo;
 class CompileTrainingData;
 class DumpRegion;
 class FileMapInfo;
+class GrowableArrayBase;
 class KlassTrainingData;
+class MethodCounters;
 class MethodTrainingData;
+class ModuleEntry;
 class outputStream;
+class PackageEntry;
 
 // Write detailed info to a mapfile to analyze contents of the AOT cache/CDS archive.
 // -Xlog:aot+map* can be used both when creating an AOT cache, or when using an AOT cache.
@@ -62,7 +67,7 @@ class AOTMapLogger : AllStatic {
     address _buffered_addr;
     address _requested_addr;
     int _bytes;
-    MetaspaceObj::Type _type;
+    MetaspaceClosureType _type;
   };
 
 public:
@@ -142,6 +147,9 @@ private:
   Thread* current);
   static void log_klass(Klass* k, address requested_addr, const char* type_name, int bytes, Thread* current);
   static void log_method(Method* m, address requested_addr, const char* type_name, int bytes, Thread* current);
+  static void log_module_entry(ModuleEntry* mod, address requested_addr, const char* type_name, int bytes, Thread* current);
+  static void log_package_entry(PackageEntry* pkg, address requested_addr, const char* type_name, int bytes, Thread* current);
+  static void log_growable_array(GrowableArrayBase* arr, address requested_addr, const char* type_name, int bytes, Thread* current);
   static void log_symbol(Symbol* s, address requested_addr, const char* type_name, int bytes, Thread* current);
   static void log_klass_training_data(KlassTrainingData* ktd, address requested_addr, const char* type_name, int bytes, Thread* current);
   static void log_method_training_data(MethodTrainingData* mtd, address requested_addr, const char* type_name, int bytes, Thread* current);

src/hotspot/share/cds/aotMappedHeapWriter.cpp

@@ -696,7 +696,7 @@ template <typename T> void AOTMappedHeapWriter::relocate_field_in_buffer(T* fiel
     // We use zero-based, 0-shift encoding, so the narrowOop is just the lower
     // 32 bits of request_referent
     intptr_t addr = cast_from_oop<intptr_t>(request_referent);
-    *((narrowOop*)field_addr_in_buffer) = checked_cast<narrowOop>(addr);
+    *((narrowOop*)field_addr_in_buffer) = CompressedOops::narrow_oop_cast(addr);
   } else {
     store_requested_oop_in_buffer<T>(field_addr_in_buffer, request_referent);
   }

src/hotspot/share/cds/aotMetaspace.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -698,6 +698,9 @@ public:
     Universe::metaspace_pointers_do(it);
     vmSymbols::metaspace_pointers_do(it);
     TrainingData::iterate_roots(it);
+    if (CDSConfig::is_dumping_full_module_graph()) {
+      ClassLoaderDataShared::iterate_roots(it);
+    }
 
     // The above code should find all the symbols that are referenced by the
     // archived classes. We just need to add the extra symbols which
@@ -795,6 +798,10 @@ void VM_PopulateDumpSharedSpace::doit() {
   _builder.make_klasses_shareable();
   AOTMetaspace::make_method_handle_intrinsics_shareable();
 
+  if (CDSConfig::is_dumping_full_module_graph()) {
+    ClassLoaderDataShared::remove_unshareable_info();
+  }
+
   dump_java_heap_objects();
   dump_shared_symbol_table(_builder.symbols());
 
@@ -1135,6 +1142,7 @@ void AOTMetaspace::dump_static_archive_impl(StaticArchiveBuilder& builder, TRAPS
     HeapShared::init_heap_writer();
     if (CDSConfig::is_dumping_full_module_graph()) {
       ClassLoaderDataShared::ensure_module_entry_tables_exist();
+      ClassLoaderDataShared::build_tables(CHECK);
       HeapShared::reset_archived_object_states(CHECK);
     }
 
@@ -2159,7 +2167,6 @@ void AOTMetaspace::initialize_shared_spaces() {
     intptr_t* buffer = (intptr_t*)dynamic_mapinfo->serialized_data();
     ReadClosure rc(&buffer, (intptr_t)SharedBaseAddress);
     DynamicArchive::serialize(&rc);
-    DynamicArchive::setup_array_klasses();
   }
 
   LogStreamHandle(Info, aot) lsh;

src/hotspot/share/cds/archiveBuilder.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2020, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -243,7 +243,7 @@ bool ArchiveBuilder::gather_klass_and_symbol(MetaspaceClosure::Ref* ref, bool re
   if (get_follow_mode(ref) != make_a_copy) {
     return false;
   }
-  if (ref->msotype() == MetaspaceObj::ClassType) {
+  if (ref->type() == MetaspaceClosureType::ClassType) {
     Klass* klass = (Klass*)ref->obj();
     assert(klass->is_klass(), "must be");
     if (!is_excluded(klass)) {
@@ -252,7 +252,7 @@ bool ArchiveBuilder::gather_klass_and_symbol(MetaspaceClosure::Ref* ref, bool re
         assert(klass->is_instance_klass(), "must be");
       }
     }
-  } else if (ref->msotype() == MetaspaceObj::SymbolType) {
+  } else if (ref->type() == MetaspaceClosureType::SymbolType) {
     // Make sure the symbol won't be GC'ed while we are dumping the archive.
     Symbol* sym = (Symbol*)ref->obj();
     sym->increment_refcount();
@@ -271,11 +271,6 @@ void ArchiveBuilder::gather_klasses_and_symbols() {
   aot_log_info(aot)("Gathering classes and symbols ... ");
   GatherKlassesAndSymbols doit(this);
   iterate_roots(&doit);
-#if INCLUDE_CDS_JAVA_HEAP
-  if (CDSConfig::is_dumping_full_module_graph()) {
-    ClassLoaderDataShared::iterate_symbols(&doit);
-  }
-#endif
   doit.finish();
 
   if (CDSConfig::is_dumping_static_archive()) {
@@ -446,14 +441,14 @@ bool ArchiveBuilder::gather_one_source_obj(MetaspaceClosure::Ref* ref, bool read
   }
 
 #ifdef ASSERT
-  if (ref->msotype() == MetaspaceObj::MethodType) {
+  if (ref->type() == MetaspaceClosureType::MethodType) {
     Method* m = (Method*)ref->obj();
     assert(!RegeneratedClasses::has_been_regenerated((address)m->method_holder()),
            "Should not archive methods in a class that has been regenerated");
   }
 #endif
 
-  if (ref->msotype() == MetaspaceObj::MethodDataType) {
+  if (ref->type() == MetaspaceClosureType::MethodDataType) {
     MethodData* md = (MethodData*)ref->obj();
     md->clean_method_data(false /* always_clean */);
   }
@@ -554,16 +549,16 @@ ArchiveBuilder::FollowMode ArchiveBuilder::get_follow_mode(MetaspaceClosure::Ref
   if (CDSConfig::is_dumping_dynamic_archive() && AOTMetaspace::in_aot_cache(obj)) {
     // Don't dump existing shared metadata again.
     return point_to_it;
-  } else if (ref->msotype() == MetaspaceObj::MethodDataType ||
-             ref->msotype() == MetaspaceObj::MethodCountersType ||
-             ref->msotype() == MetaspaceObj::KlassTrainingDataType ||
-             ref->msotype() == MetaspaceObj::MethodTrainingDataType ||
-             ref->msotype() == MetaspaceObj::CompileTrainingDataType) {
+  } else if (ref->type() == MetaspaceClosureType::MethodDataType ||
+             ref->type() == MetaspaceClosureType::MethodCountersType ||
+             ref->type() == MetaspaceClosureType::KlassTrainingDataType ||
+             ref->type() == MetaspaceClosureType::MethodTrainingDataType ||
+             ref->type() == MetaspaceClosureType::CompileTrainingDataType) {
     return (TrainingData::need_data() || TrainingData::assembling_data()) ? make_a_copy : set_to_null;
-  } else if (ref->msotype() == MetaspaceObj::AdapterHandlerEntryType) {
+  } else if (ref->type() == MetaspaceClosureType::AdapterHandlerEntryType) {
     return CDSConfig::is_dumping_adapters() ? make_a_copy : set_to_null;
   } else {
-    if (ref->msotype() == MetaspaceObj::ClassType) {
+    if (ref->type() == MetaspaceClosureType::ClassType) {
       Klass* klass = (Klass*)ref->obj();
       assert(klass->is_klass(), "must be");
       if (RegeneratedClasses::has_been_regenerated(klass)) {
@@ -571,7 +566,12 @@ ArchiveBuilder::FollowMode ArchiveBuilder::get_follow_mode(MetaspaceClosure::Ref
       }
       if (is_excluded(klass)) {
         ResourceMark rm;
-        log_debug(cds, dynamic)("Skipping class (excluded): %s", klass->external_name());
+        aot_log_trace(aot)("pointer set to null: class (excluded): %s", klass->external_name());
+        return set_to_null;
+      }
+      if (klass->is_array_klass() && CDSConfig::is_dumping_dynamic_archive()) {
+        ResourceMark rm;
+        aot_log_trace(aot)("pointer set to null: array class not supported in dynamic region: %s", klass->external_name());
         return set_to_null;
       }
     }
@@ -615,15 +615,6 @@ void ArchiveBuilder::dump_rw_metadata() {
   ResourceMark rm;
   aot_log_info(aot)("Allocating RW objects ... ");
   make_shallow_copies(&_rw_region, &_rw_src_objs);
-
-#if INCLUDE_CDS_JAVA_HEAP
-  if (CDSConfig::is_dumping_full_module_graph()) {
-    // Archive the ModuleEntry's and PackageEntry's of the 3 built-in loaders
-    char* start = rw_region()->top();
-    ClassLoaderDataShared::allocate_archived_tables();
-    alloc_stats()->record_modules(rw_region()->top() - start, /*read_only*/false);
-  }
-#endif
 }
 
 void ArchiveBuilder::dump_ro_metadata() {
@@ -632,15 +623,6 @@ void ArchiveBuilder::dump_ro_metadata() {
 
   start_dump_region(&_ro_region);
   make_shallow_copies(&_ro_region, &_ro_src_objs);
-
-#if INCLUDE_CDS_JAVA_HEAP
-  if (CDSConfig::is_dumping_full_module_graph()) {
-    char* start = ro_region()->top();
-    ClassLoaderDataShared::init_archived_tables();
-    alloc_stats()->record_modules(ro_region()->top() - start, /*read_only*/true);
-  }
-#endif
-
   RegeneratedClasses::record_regenerated_objects();
 }
 
@@ -658,7 +640,7 @@ void ArchiveBuilder::make_shallow_copy(DumpRegion *dump_region, SourceObjInfo* s
   size_t alignment = SharedSpaceObjectAlignment; // alignment for the dest pointer
 
   char* oldtop = dump_region->top();
-  if (src_info->msotype() == MetaspaceObj::ClassType) {
+  if (src_info->type() == MetaspaceClosureType::ClassType) {
     // Allocate space for a pointer directly in front of the future InstanceKlass, so
     // we can do a quick lookup from InstanceKlass* -> RunTimeClassInfo*
     // without building another hashtable. See RunTimeClassInfo::get_for()
@@ -674,7 +656,7 @@ void ArchiveBuilder::make_shallow_copy(DumpRegion *dump_region, SourceObjInfo* s
       alignment = nth_bit(ArchiveBuilder::precomputed_narrow_klass_shift());
     }
 #endif
-  } else if (src_info->msotype() == MetaspaceObj::SymbolType) {
+  } else if (src_info->type() == MetaspaceClosureType::SymbolType) {
     // Symbols may be allocated by using AllocateHeap, so their sizes
     // may be less than size_in_bytes() indicates.
     bytes = ((Symbol*)src)->byte_size();
@@ -684,7 +666,7 @@ void ArchiveBuilder::make_shallow_copy(DumpRegion *dump_region, SourceObjInfo* s
   memcpy(dest, src, bytes);
 
   // Update the hash of buffered sorted symbols for static dump so that the symbols have deterministic contents
-  if (CDSConfig::is_dumping_static_archive() && (src_info->msotype() == MetaspaceObj::SymbolType)) {
+  if (CDSConfig::is_dumping_static_archive() && (src_info->type() == MetaspaceClosureType::SymbolType)) {
     Symbol* buffered_symbol = (Symbol*)dest;
     assert(((Symbol*)src)->is_permanent(), "archived symbols must be permanent");
     buffered_symbol->update_identity_hash();
@@ -699,7 +681,7 @@ void ArchiveBuilder::make_shallow_copy(DumpRegion *dump_region, SourceObjInfo* s
     }
   }
 
-  intptr_t* archived_vtable = CppVtables::get_archived_vtable(src_info->msotype(), (address)dest);
+  intptr_t* archived_vtable = CppVtables::get_archived_vtable(src_info->type(), (address)dest);
   if (archived_vtable != nullptr) {
     *(address*)dest = (address)archived_vtable;
     ArchivePtrMarker::mark_pointer((address*)dest);
@@ -709,7 +691,7 @@ void ArchiveBuilder::make_shallow_copy(DumpRegion *dump_region, SourceObjInfo* s
   src_info->set_buffered_addr((address)dest);
 
   char* newtop = dump_region->top();
-  _alloc_stats.record(src_info->msotype(), int(newtop - oldtop), src_info->read_only());
+  _alloc_stats.record(src_info->type(), int(newtop - oldtop), src_info->read_only());
 
   DEBUG_ONLY(_alloc_stats.verify((int)dump_region->used(), src_info->read_only()));
 }
@@ -984,8 +966,6 @@ void ArchiveBuilder::make_klasses_shareable() {
 
 #undef STATS_FORMAT
 #undef STATS_PARAMS
-
-  DynamicArchive::make_array_klasses_shareable();
 }
 
 void ArchiveBuilder::make_training_data_shareable() {
@@ -994,15 +974,15 @@ void ArchiveBuilder::make_training_data_shareable() {
       return;
     }
 
-    if (info.msotype() == MetaspaceObj::KlassTrainingDataType ||
-        info.msotype() == MetaspaceObj::MethodTrainingDataType ||
-        info.msotype() == MetaspaceObj::CompileTrainingDataType) {
+    if (info.type() == MetaspaceClosureType::KlassTrainingDataType ||
+        info.type() == MetaspaceClosureType::MethodTrainingDataType ||
+        info.type() == MetaspaceClosureType::CompileTrainingDataType) {
       TrainingData* buffered_td = (TrainingData*)info.buffered_addr();
       buffered_td->remove_unshareable_info();
-    } else if (info.msotype() == MetaspaceObj::MethodDataType) {
+    } else if (info.type() == MetaspaceClosureType::MethodDataType) {
       MethodData* buffered_mdo = (MethodData*)info.buffered_addr();
       buffered_mdo->remove_unshareable_info();
-    } else if (info.msotype() == MetaspaceObj::MethodCountersType) {
+    } else if (info.type() == MetaspaceClosureType::MethodCountersType) {
       MethodCounters* buffered_mc = (MethodCounters*)info.buffered_addr();
       buffered_mc->remove_unshareable_info();
     }

src/hotspot/share/cds/archiveBuilder.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2025, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2020, 2026, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -134,13 +134,13 @@ private:
     int _size_in_bytes;
     int _id; // Each object has a unique serial ID, starting from zero. The ID is assigned
              // when the object is added into _source_objs.
-    MetaspaceObj::Type _msotype;
+    MetaspaceClosureType _type;
     address _source_addr;    // The source object to be copied.
     address _buffered_addr;  // The copy of this object insider the buffer.
   public:
     SourceObjInfo(MetaspaceClosure::Ref* ref, bool read_only, FollowMode follow_mode) :
       _ptrmap_start(0), _ptrmap_end(0), _read_only(read_only), _has_embedded_pointer(false), _follow_mode(follow_mode),
-      _size_in_bytes(ref->size() * BytesPerWord), _id(0), _msotype(ref->msotype()),
+      _size_in_bytes(ref->size() * BytesPerWord), _id(0), _type(ref->type()),
       _source_addr(ref->obj()) {
       if (follow_mode == point_to_it) {
         _buffered_addr = ref->obj();
@@ -155,7 +155,7 @@ private:
     SourceObjInfo(address src, SourceObjInfo* renegerated_obj_info) :
       _ptrmap_start(0), _ptrmap_end(0), _read_only(false),
       _follow_mode(renegerated_obj_info->_follow_mode),
-      _size_in_bytes(0), _msotype(renegerated_obj_info->_msotype),
+      _size_in_bytes(0), _type(renegerated_obj_info->_type),
       _source_addr(src),  _buffered_addr(renegerated_obj_info->_buffered_addr) {}
 
     bool should_copy() const { return _follow_mode == make_a_copy; }
@@ -182,7 +182,7 @@ private:
       }
       return _buffered_addr;
     }
-    MetaspaceObj::Type msotype() const { return _msotype; }
+    MetaspaceClosureType type() const { return _type; }
     FollowMode follow_mode() const { return _follow_mode; }
   };