Introduce StackArgumentsAccessor class for X64

src/x64/ic-x64.cc

Index: src/x64/ic-x64.cc
diff --git a/src/x64/ic-x64.cc b/src/x64/ic-x64.cc
index 6e238c76ecebaf7e5800e54153d57b4587dbd434..85fb1a0c36283b5104c3f760080c8017eb2947a0 100644
--- a/src/x64/ic-x64.cc
+++ b/src/x64/ic-x64.cc
@@ -905,7 +905,7 @@ void CallICBase::GenerateNormal(MacroAssembler* masm, int argc) {
   Label miss;
 
   // Get the receiver of the function from the stack.
-  __ movq(rdx, Operand(rsp, (argc + 1) * kPointerSize));
+  __ movq(rdx, StackOperandForArgument((argc + 1) * kPointerSize));
 
   GenerateNameDictionaryReceiverCheck(masm, rdx, rax, rbx, &miss);
 
@@ -941,7 +941,7 @@ void CallICBase::GenerateMiss(MacroAssembler* masm,
   }
 
   // Get the receiver of the function from the stack; 1 ~ return address.
-  __ movq(rdx, Operand(rsp, (argc + 1) * kPointerSize));
+  __ movq(rdx, StackOperandForArgument((argc + 1) * kPointerSize));
 
   // Enter an internal frame.
   {
@@ -965,7 +965,8 @@ void CallICBase::GenerateMiss(MacroAssembler* masm,
   // This can happen only for regular CallIC but not KeyedCallIC.
   if (id == IC::kCallIC_Miss) {
     Label invoke, global;
-    __ movq(rdx, Operand(rsp, (argc + 1) * kPointerSize));  // receiver
+    // Get the receiver of the function from the stack; 1 ~ return address.

[danno, 2013/07/31 07:48:37]

I don't understand the comment, what do you mean by "1 ~ return address"? Just
use StackOperandForReceiver as described below, then I don't think you need a
comment at all.

+    __ movq(rdx, StackOperandForArgument((argc + 1) * kPointerSize));
     __ JumpIfSmi(rdx, &invoke);
     __ CmpObjectType(rdx, JS_GLOBAL_OBJECT_TYPE, rcx);
     __ j(equal, &global);
@@ -975,7 +976,7 @@ void CallICBase::GenerateMiss(MacroAssembler* masm,
     // Patch the receiver on the stack.
     __ bind(&global);
     __ movq(rdx, FieldOperand(rdx, GlobalObject::kGlobalReceiverOffset));
-    __ movq(Operand(rsp, (argc + 1) * kPointerSize), rdx);
+    __ movq(StackOperandForArgument((argc + 1) * kPointerSize), rdx);
     __ bind(&invoke);
   }
 
@@ -1006,7 +1007,7 @@ void CallIC::GenerateMegamorphic(MacroAssembler* masm,
   // -----------------------------------
 
   // Get the receiver of the function from the stack; 1 ~ return address.
-  __ movq(rdx, Operand(rsp, (argc + 1) * kPointerSize));
+  __ movq(rdx, StackOperandForArgument((argc + 1) * kPointerSize));
   GenerateMonomorphicCacheProbe(masm, argc, Code::CALL_IC, extra_ic_state);
   GenerateMiss(masm, argc, extra_ic_state);
 }
@@ -1024,7 +1025,7 @@ void KeyedCallIC::GenerateMegamorphic(MacroAssembler* masm, int argc) {
   // -----------------------------------
 
   // Get the receiver of the function from the stack; 1 ~ return address.
-  __ movq(rdx, Operand(rsp, (argc + 1) * kPointerSize));
+  __ movq(rdx, StackOperandForArgument((argc + 1) * kPointerSize));
 
   Label do_call, slow_call, slow_load;
   Label check_number_dictionary, check_name, lookup_monomorphic_cache;
@@ -1302,7 +1303,7 @@ void KeyedCallIC::GenerateNonStrictArguments(MacroAssembler* masm,
   // rsp[(argc + 1) * 8] : argument 0 = receiver
   // -----------------------------------
   Label slow, notin;
-  __ movq(rdx, Operand(rsp, (argc + 1) * kPointerSize));
+  __ movq(rdx, StackOperandForArgument((argc + 1) * kPointerSize));

[danno, 2013/07/31 07:48:37]

Just to make it even prettier/more readible, how about introducing a
StackOperandForReceiver where you just pass argc, and it calls
StackOperandForArgument with (argc+1)?

   Operand mapped_location = GenerateMappedArgumentsLookup(
       masm, rdx, rcx, rbx, rax, r8, &notin, &slow);
   __ movq(rdi, mapped_location);