VM: Cache instructions entry point in RawFunction/RawCode.

runtime/vm/stub_code_ia32.cc

Index: runtime/vm/stub_code_ia32.cc
diff --git a/runtime/vm/stub_code_ia32.cc b/runtime/vm/stub_code_ia32.cc
index bc91284f25d78ccf6079d6453d433e1a2a382d6b..4dd59c40d199aebbbe61662f087a8982b03f9428 100644
--- a/runtime/vm/stub_code_ia32.cc
+++ b/runtime/vm/stub_code_ia32.cc
@@ -276,8 +276,7 @@ void StubCode::GenerateCallStaticFunctionStub(Assembler* assembler) {
   // Remove the stub frame as we are about to jump to the dart function.
   __ LeaveFrame();
 
-  __ movl(ECX, FieldAddress(EAX, Code::instructions_offset()));
-  __ addl(ECX, Immediate(Instructions::HeaderSize() - kHeapObjectTag));
+  __ movl(ECX, FieldAddress(EAX, Code::entry_point_offset()));
   __ jmp(ECX);
 }
 
@@ -296,8 +295,7 @@ void StubCode::GenerateFixCallersTargetStub(Assembler* assembler) {
   __ CallRuntime(kFixCallersTargetRuntimeEntry, 0);
   __ popl(EAX);  // Get Code object.
   __ popl(EDX);  // Restore arguments descriptor array.
-  __ movl(EAX, FieldAddress(EAX, Code::instructions_offset()));
-  __ addl(EAX, Immediate(Instructions::HeaderSize() - kHeapObjectTag));
+  __ movl(EAX, FieldAddress(EAX, Code::entry_point_offset()));
   __ LeaveFrame();
   __ jmp(EAX);
   __ int3();
@@ -313,8 +311,7 @@ void StubCode::GenerateFixAllocationStubTargetStub(Assembler* assembler) {
   __ pushl(raw_null);  // Setup space on stack for return value.
   __ CallRuntime(kFixAllocationStubTargetRuntimeEntry, 0);
   __ popl(EAX);  // Get Code object.
-  __ movl(EAX, FieldAddress(EAX, Code::instructions_offset()));
-  __ addl(EAX, Immediate(Instructions::HeaderSize() - kHeapObjectTag));
+  __ movl(EAX, FieldAddress(EAX, Code::entry_point_offset()));
   __ LeaveFrame();
   __ jmp(EAX);
   __ int3();
@@ -536,8 +533,7 @@ void StubCode::GenerateMegamorphicMissStub(Assembler* assembler) {
     __ Bind(&call_target_function);
   }
 
-  __ movl(EBX, FieldAddress(EAX, Function::instructions_offset()));
-  __ addl(EBX, Immediate(Instructions::HeaderSize() - kHeapObjectTag));
+  __ movl(EBX, FieldAddress(EAX, Function::entry_point_offset()));
   __ jmp(EBX);
 }
 
@@ -1451,8 +1447,7 @@ void StubCode::GenerateNArgsCheckInlineCacheStub(
   __ Bind(&call_target_function);
   __ Comment("Call target");
   // EAX: Target function.
-  __ movl(EBX, FieldAddress(EAX, Function::instructions_offset()));
-  __ addl(EBX, Immediate(Instructions::HeaderSize() - kHeapObjectTag));
+  __ movl(EBX, FieldAddress(EAX, Function::entry_point_offset()));
   if (range_collection_mode == kCollectRanges) {
     __ EnterStubFrame();
     __ pushl(ECX);
@@ -1645,10 +1640,7 @@ void StubCode::GenerateZeroArgsUnoptimizedStaticCallStub(Assembler* assembler) {
 
   // Get function and call it, if possible.
   __ movl(EAX, Address(EBX, target_offset));
-  __ movl(EBX, FieldAddress(EAX, Function::instructions_offset()));
-
-  // EBX: Target instructions.
-  __ addl(EBX, Immediate(Instructions::HeaderSize() - kHeapObjectTag));
+  __ movl(EBX, FieldAddress(EAX, Function::entry_point_offset()));
   __ jmp(EBX);
 
   if (FLAG_support_debugger) {
@@ -1696,8 +1688,7 @@ void StubCode::GenerateLazyCompileStub(Assembler* assembler) {
   __ popl(EDX);  // Restore arguments descriptor array.
   __ LeaveFrame();
 
-  __ movl(EAX, FieldAddress(EAX, Function::instructions_offset()));
-  __ addl(EAX, Immediate(Instructions::HeaderSize() - kHeapObjectTag));
+  __ movl(EAX, FieldAddress(EAX, Function::entry_point_offset()));
   __ jmp(EAX);
 }
 
@@ -1915,8 +1906,7 @@ void StubCode::GenerateOptimizeFunctionStub(Assembler* assembler) {
   __ popl(EAX);  // Discard argument.
   __ popl(EAX);  // Get Code object
   __ popl(EDX);  // Restore argument descriptor.
-  __ movl(EAX, FieldAddress(EAX, Code::instructions_offset()));
-  __ addl(EAX, Immediate(Instructions::HeaderSize() - kHeapObjectTag));
+  __ movl(EAX, FieldAddress(EAX, Code::entry_point_offset()));
   __ LeaveFrame();
   __ jmp(EAX);
   __ int3();
@@ -2073,10 +2063,7 @@ void StubCode::EmitMegamorphicLookup(
   // illegal class id was found, the target is a cache miss handler that can
   // be invoked as a normal Dart function.
   __ movl(EAX, FieldAddress(EDI, ECX, TIMES_4, base + kWordSize));
-  __ movl(target, FieldAddress(EAX, Function::instructions_offset()));
-  // TODO(srdjan): Evaluate performance impact of moving the instruction below
-  // to the call site, instead of having it here.
-  __ addl(target, Immediate(Instructions::HeaderSize() - kHeapObjectTag));
+  __ movl(target, FieldAddress(EAX, Function::entry_point_offset()));
 }