8381811: [S390] Add support for JDK-8200555

Reviewed-by: mdoerr, amitkumar

src/hotspot/cpu/s390/gc/g1/g1BarrierSetAssembler_s390.cpp

@@ -281,6 +281,7 @@ void G1BarrierSetAssembler::load_at(MacroAssembler* masm, DecoratorSet decorator
   if (on_oop && on_reference && L_handle_null == nullptr) { L_handle_null = &done; }
   CardTableBarrierSetAssembler::load_at(masm, decorators, type, src, dst, tmp1, tmp2, L_handle_null);
   if (on_oop && on_reference) {
+    assert(tmp1 != noreg && tmp2 != noreg, "need temp registers for G1 pre-barrier");
     // Generate the G1 pre-barrier code to log the value of
     // the referent field in an SATB buffer.
     g1_write_barrier_pre(masm, decorators | IS_NOT_NULL,

src/hotspot/cpu/s390/interp_masm_s390.cpp

@@ -411,7 +411,7 @@ void InterpreterMacroAssembler::load_resolved_reference_at_index(Register result
   // Load pointer for resolved_references[] objArray.
   z_lg(result, in_bytes(ConstantPool::cache_offset()), result);
   z_lg(result, in_bytes(ConstantPoolCache::resolved_references_offset()), result);
-  resolve_oop_handle(result); // Load resolved references array itself.
+  resolve_oop_handle(result, Z_R0_scratch, Z_R1_scratch); // Load resolved references array itself.
 #ifdef ASSERT
   NearLabel index_ok;
   z_lgf(Z_R0, Address(result, arrayOopDesc::length_offset_in_bytes()));

src/hotspot/cpu/s390/macroAssembler_s390.cpp

@@ -4705,16 +4705,8 @@ void MacroAssembler::oop_decoder(Register Rdst, Register Rsrc, bool maybenull, R
 }
 
 // ((OopHandle)result).resolve();
-void MacroAssembler::resolve_oop_handle(Register result) {
-  // OopHandle::resolve is an indirection.
-  z_lg(result, 0, result);
-}
-
-void MacroAssembler::load_mirror_from_const_method(Register mirror, Register const_method) {
-  mem2reg_opt(mirror, Address(const_method, ConstMethod::constants_offset()));
-  mem2reg_opt(mirror, Address(mirror, ConstantPool::pool_holder_offset()));
-  mem2reg_opt(mirror, Address(mirror, Klass::java_mirror_offset()));
-  resolve_oop_handle(mirror);
+void MacroAssembler::resolve_oop_handle(Register result, Register tmp1, Register tmp2) {
+  access_load_at(T_OBJECT, IN_NATIVE, Address(result, 0), result, tmp1, tmp2);
 }
 
 void MacroAssembler::load_method_holder(Register holder, Register method) {
@@ -5886,6 +5878,28 @@ void MacroAssembler::asm_assert_frame_size(Register expected_size, Register tmp,
 #endif // ASSERT
 }
 
+#ifdef ASSERT
+bool is_excluded(Register excluded_register[], Register reg, int n) {
+  for (int i = 0; i < n; i++) {
+    if (excluded_register[i] == reg) {
+      return true;
+    }
+  }
+  return false;
+}
+
+void MacroAssembler::clobber_volatile_registers(Register excluded_register[], int n) {
+  const int magic_number = 0x82;
+
+  for (int i = 0; i < 6 /* R0 to R5 */; i++) {
+    Register reg = as_Register(i);
+    if (!is_excluded(excluded_register, reg, n)) {
+      load_const_optimized(reg, magic_number);
+    }
+  }
+}
+#endif // ASSERT
+
 // Save and restore functions: Exclude Z_R0.
 void MacroAssembler::save_volatile_regs(Register dst, int offset, bool include_fp, bool include_flags) {
   z_stmg(Z_R1, Z_R5, offset, dst); offset += 5 * BytesPerWord;

src/hotspot/cpu/s390/macroAssembler_s390.hpp

@@ -484,6 +484,10 @@ class MacroAssembler: public Assembler {
   // Pop current C frame and restore return PC register (Z_R14).
   void pop_frame_restore_retPC(int frame_size_in_bytes);
 
+#ifdef ASSERT
+  void clobber_volatile_registers(Register excluded_register[], int n);
+#endif // ASSERT
+
   //
   // Calls
   //
@@ -885,8 +889,7 @@ class MacroAssembler: public Assembler {
   void oop_decoder(Register Rdst, Register Rsrc, bool maybenull,
                    Register Rbase = Z_R1, int pow2_offset = -1);
 
-  void resolve_oop_handle(Register result);
-  void load_mirror_from_const_method(Register mirror, Register const_method);
+  void resolve_oop_handle(Register result, Register tmp1, Register tmp2);
   void load_method_holder(Register holder, Register method);
 
   //--------------------------

src/hotspot/cpu/s390/templateInterpreterGenerator_s390.cpp

@@ -1113,6 +1113,7 @@ void TemplateInterpreterGenerator::generate_fixed_frame(bool native_call) {
   {
   // locals
   const Register local_addr = Z_ARG4;
+  const Register constants_addr = Z_ARG2;
 
   BLOCK_COMMENT("generate_fixed_frame: initialize interpreter state {");
 
@@ -1128,8 +1129,8 @@ void TemplateInterpreterGenerator::generate_fixed_frame(bool native_call) {
   __ z_stg(Z_R10, _z_ijava_state_neg(sender_sp), fp);
 
   // Load cp cache and save it at the end of this block.
-  __ z_lg(Z_R1_scratch, Address(const_method, ConstMethod::constants_offset()));
-  __ z_lg(Z_R1_scratch, Address(Z_R1_scratch, ConstantPool::cache_offset()));
+  __ z_lg(constants_addr, Address(const_method, ConstMethod::constants_offset()));
+  __ z_lg(Z_R1_scratch, Address(constants_addr, ConstantPool::cache_offset()));
 
   // z_ijava_state->method = method;
   __ z_stg(Z_method, _z_ijava_state_neg(method), fp);
@@ -1192,7 +1193,9 @@ void TemplateInterpreterGenerator::generate_fixed_frame(bool native_call) {
   __ z_stg(Z_R1_scratch, _z_ijava_state_neg(cpoolCache), fp);
 
   // Get mirror and store it in the frame as GC root for this Method*.
-  __ load_mirror_from_const_method(Z_R1_scratch, const_method);
+  __ mem2reg_opt(Z_R1_scratch, Address(constants_addr, ConstantPool::pool_holder_offset()));
+  __ mem2reg_opt(Z_R1_scratch, Address(Z_R1_scratch, Klass::java_mirror_offset()));
+  __ resolve_oop_handle(Z_R1_scratch, Z_R0_scratch, Z_R1_scratch);
   __ z_stg(Z_R1_scratch, _z_ijava_state_neg(mirror), fp);
 
   BLOCK_COMMENT("} generate_fixed_frame: initialize interpreter state");
@@ -2028,7 +2031,7 @@ address TemplateInterpreterGenerator::generate_currentThread() {
   uint64_t entry_off = __ offset();
 
   __ z_lg(Z_RET, Address(Z_thread, JavaThread::threadObj_offset()));
-  __ resolve_oop_handle(Z_RET);
+  __ resolve_oop_handle(Z_RET, Z_R0_scratch, Z_R1_scratch);
 
   // Restore caller sp for c2i case.
   __ resize_frame_absolute(Z_R10, Z_R0, true); // Cut the stack back to where the caller started.

src/hotspot/cpu/s390/templateTable_s390.cpp

@@ -480,8 +480,9 @@ void TemplateTable::fast_aldc(LdcType type) {
 
   // Convert null sentinel to null.
   __ load_const_optimized(Z_R1_scratch, (intptr_t)Universe::the_null_sentinel_addr());
-  __ resolve_oop_handle(Z_R1_scratch);
-  __ z_cg(Z_tos, Address(Z_R1_scratch));
+  __ z_lg(Z_R1_scratch, Address(Z_R1_scratch));
+  __ resolve_oop_handle(Z_R1_scratch, Z_R0_scratch, Z_R1_scratch);
+  __ z_cgr(Z_tos, Z_R1_scratch);
   __ z_brne(L_resolved);
   __ clear_reg(Z_tos);
   __ z_bru(L_resolved);
@@ -2478,7 +2479,7 @@ void TemplateTable::load_resolved_field_entry(Register obj,
   if (is_static) {
     __ load_sized_value(obj, Address(cache, ResolvedFieldEntry::field_holder_offset()), sizeof(void*), false);
     __ load_sized_value(obj, Address(obj, in_bytes(Klass::java_mirror_offset())), sizeof(void*), false);
-    __ resolve_oop_handle(obj);
+    __ resolve_oop_handle(obj, Z_R0_scratch, Z_R1_scratch);
   }
 }