Port r7868 (constant masking) to x64.

src/x64/full-codegen-x64.cc

Index: src/x64/full-codegen-x64.cc
diff --git a/src/x64/full-codegen-x64.cc b/src/x64/full-codegen-x64.cc
index a55788d10668a6ee9a97d57d3789f4ed5e5867c8..cebc09f778d6909d56d2402687320b68a5a97b4d 100644
--- a/src/x64/full-codegen-x64.cc
+++ b/src/x64/full-codegen-x64.cc
@@ -222,7 +222,7 @@ void FullCodeGenerator::Generate() {
     __ lea(rdx,
            Operand(rbp, StandardFrameConstants::kCallerSPOffset + offset));
     __ push(rdx);
-    __ Push(Smi::FromInt(num_parameters));
+    __ SafePush(Smi::FromInt(num_parameters));
     // Arguments to ArgumentsAccessStub:
     //   function, receiver address, parameter count.
     // The stub will rewrite receiver and parameter count if the previous
@@ -504,12 +504,20 @@ void FullCodeGenerator::EffectContext::Plug(Handle<Object> lit) const {
 
 void FullCodeGenerator::AccumulatorValueContext::Plug(
     Handle<Object> lit) const {
-  __ Move(result_register(), lit);
+  if (lit->IsSmi()) {
+    __ SafeMove(result_register(), Smi::cast(*lit));
+  } else {
+    __ Move(result_register(), lit);
+  }
 }
 
 
 void FullCodeGenerator::StackValueContext::Plug(Handle<Object> lit) const {
-  __ Push(lit);
+  if (lit->IsSmi()) {
+    __ SafePush(Smi::cast(*lit));
+  } else {
+    __ Push(lit);
+  }
 }
 
 
@@ -2455,7 +2463,7 @@ void FullCodeGenerator::VisitCallNew(CallNew* expr) {
   SetSourcePosition(expr->position());
 
   // Load function and argument count into rdi and rax.
-  __ Set(rax, arg_count);
+  __ SafeSet(rax, arg_count);
   __ movq(rdi, Operand(rsp, arg_count * kPointerSize));
 
   // Record call targets in unoptimized code, but not in the snapshot.
@@ -2812,7 +2820,7 @@ void FullCodeGenerator::EmitArguments(CallRuntime* expr) {
   // parameter count in rax.
   VisitForAccumulatorValue(args->at(0));
   __ movq(rdx, rax);
-  __ Move(rax, Smi::FromInt(info_->scope()->num_parameters()));
+  __ SafeMove(rax, Smi::FromInt(info_->scope()->num_parameters()));

[Erik Corry, 2012/06/26 12:26:40]

Can this ever make a difference when kMaxNumFunctionParameters is 32k?

   ArgumentsAccessStub stub(ArgumentsAccessStub::READ_ELEMENT);
   __ CallStub(&stub);
   context()->Plug(rax);
@@ -2824,7 +2832,7 @@ void FullCodeGenerator::EmitArgumentsLength(CallRuntime* expr) {
 
   Label exit;
   // Get the number of formal parameters.
-  __ Move(rax, Smi::FromInt(info_->scope()->num_parameters()));
+  __ SafeMove(rax, Smi::FromInt(info_->scope()->num_parameters()));
 
   // Check if the calling frame is an arguments adaptor frame.
   __ movq(rbx, Operand(rbp, StandardFrameConstants::kCallerFPOffset));