Remove isolate pointer from context objects.

runtime/vm/stub_code_x64.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/assembler.h"
 #include "vm/compiler.h"
 #include "vm/dart_entry.h"
@@ skipping 26 matching lines @@
 // Must preserve callee saved registers R12 and R13.
 void StubCode::GenerateCallToRuntimeStub(Assembler* assembler) {
   ASSERT((R12 != CTX) && (R13 != CTX));
   const intptr_t isolate_offset = NativeArguments::isolate_offset();
   const intptr_t argc_tag_offset = NativeArguments::argc_tag_offset();
   const intptr_t argv_offset = NativeArguments::argv_offset();
   const intptr_t retval_offset = NativeArguments::retval_offset();
 
   __ EnterFrame(0);
 
-  // Load current Isolate pointer from Context structure into RAX.
-  __ movq(RAX, FieldAddress(CTX, Context::isolate_offset()));
+  __ LoadIsolate(RAX);
 
   // Save exit frame information to enable stack walking as we are about
   // to transition to Dart VM C++ code.
   __ movq(Address(RAX, Isolate::top_exit_frame_info_offset()), RSP);
 
   // Save current Context pointer into Isolate structure.
   __ movq(Address(RAX, Isolate::top_context_offset()), CTX);
 
   // Cache Isolate pointer into CTX while executing runtime code.
   __ movq(CTX, RAX);
@@ skipping 90 matching lines @@
       NativeArguments::isolate_offset() + native_args_struct_offset;
   const intptr_t argc_tag_offset =
       NativeArguments::argc_tag_offset() + native_args_struct_offset;
   const intptr_t argv_offset =
       NativeArguments::argv_offset() + native_args_struct_offset;
   const intptr_t retval_offset =
       NativeArguments::retval_offset() + native_args_struct_offset;
 
   __ EnterFrame(0);
 
-  // Load current Isolate pointer from Context structure into R8.
-  __ movq(R8, FieldAddress(CTX, Context::isolate_offset()));
+  __ LoadIsolate(R8);
 
   // Save exit frame information to enable stack walking as we are about
   // to transition to native code.
   __ movq(Address(R8, Isolate::top_exit_frame_info_offset()), RSP);
 
 // Save current Context pointer into Isolate structure.
   __ movq(Address(R8, Isolate::top_context_offset()), CTX);
 
   // Cache Isolate pointer into CTX while executing native code.
   __ movq(CTX, R8);
@@ skipping 67 matching lines @@
       NativeArguments::isolate_offset() + native_args_struct_offset;
   const intptr_t argc_tag_offset =
       NativeArguments::argc_tag_offset() + native_args_struct_offset;
   const intptr_t argv_offset =
       NativeArguments::argv_offset() + native_args_struct_offset;
   const intptr_t retval_offset =
       NativeArguments::retval_offset() + native_args_struct_offset;
 
   __ EnterFrame(0);
 
-  // Load current Isolate pointer from Context structure into R8.
-  __ movq(R8, FieldAddress(CTX, Context::isolate_offset()));
+  __ LoadIsolate(R8);
 
   // Save exit frame information to enable stack walking as we are about
   // to transition to native code.
   __ movq(Address(R8, Isolate::top_exit_frame_info_offset()), RSP);
 
   // Save current Context pointer into Isolate structure.
   __ movq(Address(R8, Isolate::top_context_offset()), CTX);
 
   // Cache Isolate pointer into CTX while executing native code.
   __ movq(CTX, R8);
@@ skipping 712 matching lines @@
       __ orq(R13,
              Immediate(RawObject::ClassIdTag::encode(cid)));
       __ movq(FieldAddress(RAX, Context::tags_offset()), R13);  // Tags.
     }
 
     // Setup up number of context variables field.
     // RAX: new object.
     // R10: number of context variables as integer value (not object).
     __ movq(FieldAddress(RAX, Context::num_variables_offset()), R10);
 
-    // Setup isolate field.
-    // RAX: new object.
-    // R10: number of context variables.
-    // R13: Isolate, not an object.
-    __ LoadIsolate(R13);
-    __ movq(FieldAddress(RAX, Context::isolate_offset()), R13);
-
     // Setup the parent field.
     // RAX: new object.
     // R10: number of context variables.
     __ movq(FieldAddress(RAX, Context::parent_offset()), R12);
 
     // Initialize the context variables.
     // RAX: new object.
     // R10: number of context variables.
     {
       Label loop, entry;
@@ skipping 748 matching lines @@
   __ popq(RAX);  // Address of original.
   __ LeaveStubFrame();
   __ jmp(RAX);   // Jump to original stub.
 }
 
 
 // Called only from unoptimized code.
 void StubCode::GenerateDebugStepCheckStub(Assembler* assembler) {
   // Check single stepping.
   Label stepping, done_stepping;
-  __ movq(RAX, FieldAddress(CTX, Context::isolate_offset()));
+  __ LoadIsolate(RAX);
   __ movzxb(RAX, Address(RAX, Isolate::single_step_offset()));
   __ cmpq(RAX, Immediate(0));
   __ j(NOT_EQUAL, &stepping, Assembler::kNearJump);
   __ Bind(&done_stepping);
   __ ret();
 
   __ Bind(&stepping);
   __ EnterStubFrame();
   __ CallRuntime(kSingleStepHandlerRuntimeEntry, 0);
   __ LeaveStubFrame();
@@ skipping 246 matching lines @@
 
 // Called only from unoptimized code. All relevant registers have been saved.
 // TOS + 0: return address
 // TOS + 1: right argument.
 // TOS + 2: left argument.
 // Returns ZF set.
 void StubCode::GenerateUnoptimizedIdenticalWithNumberCheckStub(
     Assembler* assembler) {
   // Check single stepping.
   Label stepping, done_stepping;
-  __ movq(RAX, FieldAddress(CTX, Context::isolate_offset()));
+  __ LoadIsolate(RAX);
   __ movzxb(RAX, Address(RAX, Isolate::single_step_offset()));
   __ cmpq(RAX, Immediate(0));
   __ j(NOT_EQUAL, &stepping);
   __ Bind(&done_stepping);
 
   const Register left = RAX;
   const Register right = RDX;
 
   __ movq(left, Address(RSP, 2 * kWordSize));
   __ movq(right, Address(RSP, 1 * kWordSize));
@@ skipping 20 matching lines @@
 
   __ movq(left, Address(RSP, 2 * kWordSize));
   __ movq(right, Address(RSP, 1 * kWordSize));
   GenerateIdenticalWithNumberCheckStub(assembler, left, right);
   __ ret();
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64