Add support for keyed-call on arrays of fast elements

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 dc6ddf9f7e41595e10b58c033e04fdc4cd958e93..242f7493401e86cb96bf214a2dde9eb071e52268 100644
--- a/src/x64/lithium-codegen-x64.cc
+++ b/src/x64/lithium-codegen-x64.cc
@@ -415,11 +415,23 @@ Handle<Object> LCodeGen::ToHandle(LConstantOperand* op) const {
 }
 
 
+static int ArgumentsOffsetWithoutFrame(int index) {
+  ASSERT(index < 0);
+  return -(index + 1) * kPointerSize + kPCOnStackSize;
+}
+
+
 Operand LCodeGen::ToOperand(LOperand* op) const {
   // Does not handle registers. In X64 assembler, plain registers are not
   // representable as an Operand.
   ASSERT(op->IsStackSlot() || op->IsDoubleStackSlot());
-  return Operand(rbp, StackSlotOffset(op->index()));
+  if (NeedsEagerFrame()) {
+    return Operand(rbp, StackSlotOffset(op->index()));
+  } else {
+    // Retrieve parameter without eager stack-frame relative to the
+    // stack-pointer.
+    return Operand(rsp, ArgumentsOffsetWithoutFrame(op->index()));
+  }
 }
 
 
@@ -3910,7 +3922,12 @@ void LCodeGen::DoCallFunction(LCallFunction* instr) {
 
   int arity = instr->arity();
   CallFunctionStub stub(arity, NO_CALL_FUNCTION_FLAGS);
-  CallCode(stub.GetCode(isolate()), RelocInfo::CODE_TARGET, instr);
+  if (instr->hydrogen()->IsTailCall()) {
+    if (NeedsEagerFrame()) __ leave();
+    __ jmp(stub.GetCode(isolate()), RelocInfo::CODE_TARGET);
+  } else {
+    CallCode(stub.GetCode(isolate()), RelocInfo::CODE_TARGET, instr);
+  }
 }