Fix calls of strict mode function with an implicit receiver.

src/x64/lithium-codegen-x64.cc

Index: src/x64/lithium-codegen-x64.cc
diff --git a/src/x64/lithium-codegen-x64.cc b/src/x64/lithium-codegen-x64.cc
index 7c78a4e790dd11e32ce90f37781478729c5339cb..97177de6ea3577b68f48a4933c649de2b3aab0c2 100644
--- a/src/x64/lithium-codegen-x64.cc
+++ b/src/x64/lithium-codegen-x64.cc
@@ -140,6 +140,21 @@ bool LCodeGen::GeneratePrologue() {
   }
 #endif
 
+  // Strict mode functions need to replace the receiver with undefined
+  // when called as functions (without an explicit receiver
+  // object). rcx is zero for method calls and non-zero for function
+  // calls.
+  if (info_->is_strict_mode()) {
+    Label ok;
+    __ testq(rcx, rcx);
+    __ j(zero, &ok, Label::kNear);
+    // +1 for return address.
+    int receiver_offset = (scope()->num_parameters() + 1) * kPointerSize;
+    __ LoadRoot(kScratchRegister, Heap::kUndefinedValueRootIndex);
+    __ movq(Operand(rsp, receiver_offset), kScratchRegister);
+    __ bind(&ok);
+  }
+
   __ push(rbp);  // Caller's frame pointer.
   __ movq(rbp, rsp);
   __ push(rsi);  // Callee's context.
@@ -2688,7 +2703,8 @@ void LCodeGen::DoGlobalReceiver(LGlobalReceiver* instr) {
 
 void LCodeGen::CallKnownFunction(Handle<JSFunction> function,
                                  int arity,
-                                 LInstruction* instr) {
+                                 LInstruction* instr,
+                                 CallKind call_kind) {
   // Change context if needed.
   bool change_context =
       (info()->closure()->context() != function->context()) ||
@@ -2708,6 +2724,7 @@ void LCodeGen::CallKnownFunction(Handle<JSFunction> function,
   RecordPosition(pointers->position());
 
   // Invoke function.
+  __ SetCallKind(rcx, call_kind);
   if (*function == *info()->closure()) {
     __ CallSelf();
   } else {
@@ -2725,7 +2742,10 @@ void LCodeGen::CallKnownFunction(Handle<JSFunction> function,
 void LCodeGen::DoCallConstantFunction(LCallConstantFunction* instr) {
   ASSERT(ToRegister(instr->result()).is(rax));
   __ Move(rdi, instr->function());
-  CallKnownFunction(instr->function(), instr->arity(), instr);
+  CallKnownFunction(instr->function(),
+                    instr->arity(),
+                    instr,
+                    CALL_AS_METHOD);
 }
 
 
@@ -3076,10 +3096,11 @@ void LCodeGen::DoCallNamed(LCallNamed* instr) {
   ASSERT(ToRegister(instr->result()).is(rax));
 
   int arity = instr->arity();
-  Handle<Code> ic = isolate()->stub_cache()->ComputeCallInitialize(
-      arity, NOT_IN_LOOP);
+  RelocInfo::Mode mode = RelocInfo::CODE_TARGET;
+  Handle<Code> ic =
+      isolate()->stub_cache()->ComputeCallInitialize(arity, NOT_IN_LOOP, mode);
   __ Move(rcx, instr->name());
-  CallCode(ic, RelocInfo::CODE_TARGET, instr);
+  CallCode(ic, mode, instr);
   __ movq(rsi, Operand(rbp, StandardFrameConstants::kContextOffset));
 }
 
@@ -3088,7 +3109,7 @@ void LCodeGen::DoCallFunction(LCallFunction* instr) {
   ASSERT(ToRegister(instr->result()).is(rax));
 
   int arity = instr->arity();
-  CallFunctionStub stub(arity, NOT_IN_LOOP, RECEIVER_MIGHT_BE_VALUE);
+  CallFunctionStub stub(arity, NOT_IN_LOOP, RECEIVER_MIGHT_BE_IMPLICIT);
   CallCode(stub.GetCode(), RelocInfo::CODE_TARGET, instr);
   __ movq(rsi, Operand(rbp, StandardFrameConstants::kContextOffset));
   __ Drop(1);
@@ -3098,10 +3119,11 @@ void LCodeGen::DoCallFunction(LCallFunction* instr) {
 void LCodeGen::DoCallGlobal(LCallGlobal* instr) {
   ASSERT(ToRegister(instr->result()).is(rax));
   int arity = instr->arity();
-  Handle<Code> ic = isolate()->stub_cache()->ComputeCallInitialize(
-      arity, NOT_IN_LOOP);
+  RelocInfo::Mode mode = RelocInfo::CODE_TARGET_CONTEXT;
+  Handle<Code> ic =
+      isolate()->stub_cache()->ComputeCallInitialize(arity, NOT_IN_LOOP, mode);
   __ Move(rcx, instr->name());
-  CallCode(ic, RelocInfo::CODE_TARGET_CONTEXT, instr);
+  CallCode(ic, mode, instr);
   __ movq(rsi, Operand(rbp, StandardFrameConstants::kContextOffset));
 }
 
@@ -3109,7 +3131,7 @@ void LCodeGen::DoCallGlobal(LCallGlobal* instr) {
 void LCodeGen::DoCallKnownGlobal(LCallKnownGlobal* instr) {
   ASSERT(ToRegister(instr->result()).is(rax));
   __ Move(rdi, instr->target());
-  CallKnownFunction(instr->target(), instr->arity(), instr);
+  CallKnownFunction(instr->target(), instr->arity(), instr, CALL_AS_FUNCTION);
 }