diff --git a/make/autoconf/flags-cflags.m4 b/make/autoconf/flags-cflags.m4
index e9959196acb..cfea63f0e3b 100644
--- a/make/autoconf/flags-cflags.m4
+++ b/make/autoconf/flags-cflags.m4
@@ -51,6 +51,14 @@ AC_DEFUN([FLAGS_SETUP_SHARED_LIBS],
       SET_SHARED_LIBRARY_NAME='-Wl,-install_name,@rpath/[$]1'
       SET_SHARED_LIBRARY_MAPFILE='-Wl,-exported_symbols_list,[$]1'
 
+    elif test "x$OPENJDK_TARGET_OS" = xaix; then
+      # Linking is different on aix
+      SHARED_LIBRARY_FLAGS="-shared -Wl,-bM:SRE -Wl,-bnoentry"
+      SET_EXECUTABLE_ORIGIN=""
+      SET_SHARED_LIBRARY_ORIGIN=''
+      SET_SHARED_LIBRARY_NAME=''
+      SET_SHARED_LIBRARY_MAPFILE=''
+
     else
       # Default works for linux, might work on other platforms as well.
       SHARED_LIBRARY_FLAGS='-shared'
@@ -206,7 +214,6 @@ AC_DEFUN([FLAGS_SETUP_WARNINGS],
       WARNINGS_ENABLE_ALL="-Wall -Wextra -Wformat=2 $WARNINGS_ENABLE_ADDITIONAL"
 
       DISABLED_WARNINGS="unknown-warning-option unused-parameter unused"
-
       ;;
 
     xlc)
@@ -284,9 +291,15 @@ AC_DEFUN([FLAGS_SETUP_OPTIMIZATION],
       C_O_FLAG_NONE="${C_O_FLAG_NONE} ${DISABLE_FORTIFY_CFLAGS}"
     fi
   elif test "x$TOOLCHAIN_TYPE" = xclang; then
-    C_O_FLAG_HIGHEST_JVM="-O3"
-    C_O_FLAG_HIGHEST="-O3"
-    C_O_FLAG_HI="-O3"
+    if test "x$OPENJDK_TARGET_OS" = xaix; then
+      C_O_FLAG_HIGHEST_JVM="-O3 -finline-functions"
+      C_O_FLAG_HIGHEST="-O3 -finline-functions"
+      C_O_FLAG_HI="-O3 -finline-functions"
+    else
+      C_O_FLAG_HIGHEST_JVM="-O3"
+      C_O_FLAG_HIGHEST="-O3"
+      C_O_FLAG_HI="-O3"
+    fi
     C_O_FLAG_NORM="-O2"
     C_O_FLAG_DEBUG_JVM="-O0"
     C_O_FLAG_SIZE="-Os"
@@ -458,6 +471,9 @@ AC_DEFUN([FLAGS_SETUP_CFLAGS_HELPER],
       # so for debug we build with '-qpic=large -bbigtoc'.
       DEBUG_CFLAGS_JVM="-qpic=large"
     fi
+    if test "x$TOOLCHAIN_TYPE" = xclang && test "x$OPENJDK_TARGET_OS" = xaix; then
+      DEBUG_CFLAGS_JVM="-fpic -mcmodel=large"
+    fi
   fi
 
   if test "x$DEBUG_LEVEL" != xrelease; then
@@ -493,6 +509,12 @@ AC_DEFUN([FLAGS_SETUP_CFLAGS_HELPER],
         -fvisibility=hidden -fno-strict-aliasing -fno-omit-frame-pointer"
   fi
 
+  if test "x$TOOLCHAIN_TYPE" = xclang && test "x$OPENJDK_TARGET_OS" = xaix; then
+    # clang compiler on aix needs -ffunction-sections
+    TOOLCHAIN_CFLAGS_JVM="$TOOLCHAIN_CFLAGS_JVM -ffunction-sections -ftls-model -fno-math-errno -fstack-protector"
+    TOOLCHAIN_CFLAGS_JDK="-ffunction-sections -fsigned-char -fstack-protector"
+  fi
+
   if test "x$TOOLCHAIN_TYPE" = xgcc; then
     TOOLCHAIN_CFLAGS_JVM="$TOOLCHAIN_CFLAGS_JVM -fstack-protector"
     TOOLCHAIN_CFLAGS_JDK="-pipe -fstack-protector"
@@ -601,6 +623,9 @@ AC_DEFUN([FLAGS_SETUP_CFLAGS_HELPER],
   if test "x$TOOLCHAIN_TYPE" = xgcc || test "x$TOOLCHAIN_TYPE" = xclang; then
     PICFLAG="-fPIC"
     PIEFLAG="-fPIE"
+  elif test "x$TOOLCHAIN_TYPE" = xclang && test "x$OPENJDK_TARGET_OS" = xaix; then
+    JVM_PICFLAG="-fpic -mcmodel=large -Wl,-bbigtoc
+    JDK_PICFLAG="-fpic
   elif test "x$TOOLCHAIN_TYPE" = xxlc; then
     # '-qpic' defaults to 'qpic=small'. This means that the compiler generates only
     # one instruction for accessing the TOC. If the TOC grows larger than 64K, the linker
diff --git a/make/autoconf/flags-ldflags.m4 b/make/autoconf/flags-ldflags.m4
index c1e7218ca2c..e5c345fdef1 100644
--- a/make/autoconf/flags-ldflags.m4
+++ b/make/autoconf/flags-ldflags.m4
@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2011, 2022, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2011, 2023, 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
@@ -75,7 +75,11 @@ AC_DEFUN([FLAGS_SETUP_LDFLAGS_HELPER],
   elif test "x$TOOLCHAIN_TYPE" = xclang; then
     BASIC_LDFLAGS_JVM_ONLY="-mno-omit-leaf-frame-pointer -mstack-alignment=16 \
         -fPIC"
-
+    if test "x$OPENJDK_TARGET_OS" = xaix; then
+      BASIC_LDFLAGS="-Wl,-b64 -Wl,-brtl -Wl,-bnorwexec -Wl,-bnolibpath -Wl,-bnoexpall \
+        -Wl,-bernotok -Wl,-bdatapsize:64k -Wl,-btextpsize:64k -Wl,-bstackpsize:64k"
+      BASIC_LDFLAGS_JVM_ONLY="$BASIC_LDFLAGS_JVM_ONLY -Wl,-lC_r -Wl,-bbigtoc"
+    fi
   elif test "x$TOOLCHAIN_TYPE" = xxlc; then
     BASIC_LDFLAGS="-b64 -brtl -bnorwexec -bnolibpath -bnoexpall -bernotok -btextpsize:64K \
         -bdatapsize:64K -bstackpsize:64K"
@@ -88,7 +92,8 @@ AC_DEFUN([FLAGS_SETUP_LDFLAGS_HELPER],
     BASIC_LDFLAGS_JVM_ONLY="-opt:icf,8 -subsystem:windows"
   fi
 
-  if test "x$TOOLCHAIN_TYPE" = xgcc || test "x$TOOLCHAIN_TYPE" = xclang; then
+  if (test "x$TOOLCHAIN_TYPE" = xgcc || test "x$TOOLCHAIN_TYPE" = xclang) \
+      && test "x$OPENJDK_TARGET_OS" != xaix; then
     if test -n "$HAS_NOEXECSTACK"; then
       BASIC_LDFLAGS="$BASIC_LDFLAGS -Wl,-z,noexecstack"
     fi
@@ -116,6 +121,14 @@ AC_DEFUN([FLAGS_SETUP_LDFLAGS_HELPER],
     if test "x$DEBUG_LEVEL" != xrelease; then
       DEBUGLEVEL_LDFLAGS_JVM_ONLY="$DEBUGLEVEL_LDFLAGS_JVM_ONLY -bbigtoc"
     fi
+
+  elif test "x$TOOLCHAIN_TYPE" = xclang && test "x$OPENJDK_TARGET_OS" = xaix; then
+    # We need '-fpic' or '-fpic -mcmodel=large -Wl,-bbigtoc' if the TOC overflows.
+    # Hotspot now overflows its 64K TOC (currently only for debug),
+    # so we build with '-fpic -mcmodel=large -Wl,-bbigtoc'.
+    if test "x$DEBUG_LEVEL" != xrelease; then
+      DEBUGLEVEL_LDFLAGS_JVM_ONLY="$DEBUGLEVEL_LDFLAGS_JVM_ONLY -Wl,-bbigtoc"
+    fi
   fi
 
   # Setup LDFLAGS for linking executables
diff --git a/make/autoconf/toolchain.m4 b/make/autoconf/toolchain.m4
index 1ae0902e3f3..c89aab11d4b 100644
--- a/make/autoconf/toolchain.m4
+++ b/make/autoconf/toolchain.m4
@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2011, 2022, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2011, 2023, 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
@@ -40,7 +40,7 @@ VALID_TOOLCHAINS_all="gcc clang xlc microsoft"
 # These toolchains are valid on different platforms
 VALID_TOOLCHAINS_linux="gcc clang"
 VALID_TOOLCHAINS_macosx="clang"
-VALID_TOOLCHAINS_aix="xlc"
+VALID_TOOLCHAINS_aix="xlc clang"
 VALID_TOOLCHAINS_windows="microsoft"
 
 # Toolchain descriptions
@@ -234,6 +234,25 @@ AC_DEFUN_ONCE([TOOLCHAIN_DETERMINE_TOOLCHAIN_TYPE],
   # First toolchain type in the list is the default
   DEFAULT_TOOLCHAIN=${VALID_TOOLCHAINS%% *}
 
+  # On AIX the default toolchain depends on the installed (found) compiler
+  #   xlclang++     -> xlc toolchain
+  #   ibm-clang++_r -> clang toolchain
+  # The compiler is searched on the PATH and TOOLCHAIN_PATH
+  # xlclang++ has precedence over ibm-clang++_r if both are installed
+  if test "x$OPENJDK_TARGET_OS" = xaix; then
+    DEFAULT_TOOLCHAIN="clang"
+    if test "x$TOOLCHAIN_PATH" != x; then
+      if test -e ${TOOLCHAIN_PATH}/xlclang++; then
+        DEFAULT_TOOLCHAIN="xlc"
+      fi
+    else
+      UTIL_LOOKUP_PROGS(XLCLANG_TEST_PATH, xlclang++)
+      if test "x$XLCLANG_TEST_PATH" != x; then
+        DEFAULT_TOOLCHAIN="xlc"
+      fi
+    fi
+  fi
+
   if test "x$with_toolchain_type" = xlist; then
     # List all toolchains
     AC_MSG_NOTICE([The following toolchains are valid on this platform:])
@@ -263,22 +282,40 @@ AC_DEFUN_ONCE([TOOLCHAIN_DETERMINE_TOOLCHAIN_TYPE],
     if test "x$TOOLCHAIN_PATH" != x; then
       XLC_TEST_PATH=${TOOLCHAIN_PATH}/
     fi
-
-    XLCLANG_VERSION_OUTPUT=`${XLC_TEST_PATH}xlclang++ -qversion 2>&1 | $HEAD -n 1`
-    $ECHO "$XLCLANG_VERSION_OUTPUT" | $GREP "IBM XL C/C++ for AIX" > /dev/null
-    if test $? -eq 0; then
-      AC_MSG_NOTICE([xlclang++ output: $XLCLANG_VERSION_OUTPUT])
+    if test "x$TOOLCHAIN_TYPE" = xclang; then
+      TOOLCHAIN_DESCRIPTION_clang="IBM Open XL C/C++"
+      XLCLANG_VERSION_OUTPUT=`${XLC_TEST_PATH}ibm-clang++_r --version 2>&1 | $HEAD -n 1`
+      $ECHO "$XLCLANG_VERSION_OUTPUT" | $GREP "IBM Open XL C/C++ for AIX" > /dev/null
+      if test $? -eq 0; then
+        AC_MSG_NOTICE([ibm-clang++_r output: $XLCLANG_VERSION_OUTPUT])
+      else
+        AC_MSG_ERROR([ibm-clang++_r version output check failed, output: $XLCLANG_VERSION_OUTPUT])
+      fi
     else
-      AC_MSG_ERROR([xlclang++ version output check failed, output: $XLCLANG_VERSION_OUTPUT])
+      XLCLANG_VERSION_OUTPUT=`${XLC_TEST_PATH}xlclang++ -qversion 2>&1 | $HEAD -n 1`
+      $ECHO "$XLCLANG_VERSION_OUTPUT" | $GREP "IBM XL C/C++ for AIX" > /dev/null
+      if test $? -eq 0; then
+        AC_MSG_NOTICE([xlclang++ output: $XLCLANG_VERSION_OUTPUT])
+      else
+        AC_MSG_ERROR([xlclang++ version output check failed, output: $XLCLANG_VERSION_OUTPUT])
+      fi
     fi
   fi
 
-  TOOLCHAIN_CC_BINARY_clang="clang"
+  if test "x$OPENJDK_TARGET_OS" = xaix; then
+    TOOLCHAIN_CC_BINARY_clang="ibm-clang_r"
+  else
+    TOOLCHAIN_CC_BINARY_clang="clang"
+  fi
   TOOLCHAIN_CC_BINARY_gcc="gcc"
   TOOLCHAIN_CC_BINARY_microsoft="cl"
   TOOLCHAIN_CC_BINARY_xlc="xlclang"
 
-  TOOLCHAIN_CXX_BINARY_clang="clang++"
+  if test "x$OPENJDK_TARGET_OS" = xaix; then
+    TOOLCHAIN_CXX_BINARY_clang="ibm-clang++_r"
+  else
+    TOOLCHAIN_CXX_BINARY_clang="clang++"
+  fi
   TOOLCHAIN_CXX_BINARY_gcc="g++"
   TOOLCHAIN_CXX_BINARY_microsoft="cl"
   TOOLCHAIN_CXX_BINARY_xlc="xlclang++"
@@ -966,7 +1003,11 @@ AC_DEFUN_ONCE([TOOLCHAIN_MISC_CHECKS],
   # Setup hotspot lecagy names for toolchains
   HOTSPOT_TOOLCHAIN_TYPE=$TOOLCHAIN_TYPE
   if test "x$TOOLCHAIN_TYPE" = xclang; then
-    HOTSPOT_TOOLCHAIN_TYPE=gcc
+    if test "x$OPENJDK_TARGET_OS" = xaix; then
+      HOTSPOT_TOOLCHAIN_TYPE=xlc
+    else
+      HOTSPOT_TOOLCHAIN_TYPE=gcc
+    fi
   elif test "x$TOOLCHAIN_TYPE" = xmicrosoft; then
     HOTSPOT_TOOLCHAIN_TYPE=visCPP
   fi
diff --git a/make/hotspot/gensrc/GensrcAdlc.gmk b/make/hotspot/gensrc/GensrcAdlc.gmk
index 5c8989e3efd..1005bc5000b 100644
--- a/make/hotspot/gensrc/GensrcAdlc.gmk
+++ b/make/hotspot/gensrc/GensrcAdlc.gmk
@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2013, 2022, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2013, 2023, Oracle and/or its affiliates. All rights reserved.
 # DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 #
 # This code is free software; you can redistribute it and/or modify it
@@ -37,8 +37,13 @@ ifeq ($(call check-jvm-feature, compiler2), true)
   ifeq ($(call isBuildOs, linux), true)
     ADLC_CFLAGS := -fno-exceptions -DLINUX
   else ifeq ($(call isBuildOs, aix), true)
-    ADLC_LDFLAGS += -q64
-    ADLC_CFLAGS := -qnortti -qeh -q64 -DAIX
+    ifeq ($(TOOLCHAIN_TYPE), clang)
+      ADLC_LDFLAGS += -m64
+      ADLC_CFLAGS := -fno-rtti -fexceptions -ffunction-sections -m64 -DAIX
+    else
+      ADLC_LDFLAGS += -q64
+      ADLC_CFLAGS := -qnortti -qeh -q64 -DAIX
+    endif
   else ifeq ($(call isBuildOs, windows), true)
     ADLC_LDFLAGS += -nologo
     ADLC_CFLAGS := -nologo -EHsc
diff --git a/make/hotspot/lib/JvmOverrideFiles.gmk b/make/hotspot/lib/JvmOverrideFiles.gmk
index 377018cdb51..b50d6f8bb36 100644
--- a/make/hotspot/lib/JvmOverrideFiles.gmk
+++ b/make/hotspot/lib/JvmOverrideFiles.gmk
@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2013, 2021, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2013, 2023, 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
@@ -109,7 +109,11 @@ else ifeq ($(call isTargetOs, macosx), true)
   endif
 
 else ifeq ($(call isTargetOs, aix), true)
-  BUILD_LIBJVM_synchronizer.cpp_CXXFLAGS := -qnoinline
+  ifeq ($(TOOLCHAIN_TYPE), clang)
+    BUILD_LIBJVM_synchronizer.cpp_CXXFLAGS := -fno-inline
+  else
+    BUILD_LIBJVM_synchronizer.cpp_CXXFLAGS := -qnoinline
+  endif
   BUILD_LIBJVM_sharedRuntimeTrans.cpp_CXXFLAGS := $(CXX_O_FLAG_NONE)
   # Disable aggressive optimizations for functions in sharedRuntimeTrig.cpp
   # and sharedRuntimeTrans.cpp on ppc64.
diff --git a/src/hotspot/share/utilities/globalDefinitions_xlc.hpp b/src/hotspot/share/utilities/globalDefinitions_xlc.hpp
index 518a09f90a7..edeb730132b 100644
--- a/src/hotspot/share/utilities/globalDefinitions_xlc.hpp
+++ b/src/hotspot/share/utilities/globalDefinitions_xlc.hpp
@@ -1,6 +1,6 @@
 /*
- * Copyright (c) 1998, 2022, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2012, 2021 SAP SE. All rights reserved.
+ * Copyright (c) 1998, 2023, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2023 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
@@ -56,14 +56,23 @@
   #if __ibmxl_version__ < 16
   #error "xlc < 16 not supported"
   #endif
+#elif defined(__open_xl_version__)
+  #if __open_xl_version__ < 17
+  #error "open xlc < 17 not supported"
+  #endif
 #else
-  #error "xlc < 16 not supported, macro __ibmxl_version__ not found"
+  #error "xlc version not supported, macro __ibmxl_version__ or __open_xl_version__ not found"
 #endif
 
 #ifndef _AIX
 #error "missing AIX-specific definition _AIX"
 #endif
 
+// Shortcut for the new xlc 17 compiler
+#if defined(AIX) && defined(__open_xl_version__) && __open_xl_version__ >= 17
+#define AIX_XLC_GE_17
+#endif
+
 // Use XLC compiler builtins instead of inline assembler
 #define USE_XLC_BUILTINS