Customized support for feedback on calls to Array.

src/x64/code-stubs-x64.cc

Index: src/x64/code-stubs-x64.cc
diff --git a/src/x64/code-stubs-x64.cc b/src/x64/code-stubs-x64.cc
index 0e53eb390ed1bafc32a948c663c84e7b528f4650..af8d21beb571d267b8888d81076cccb875324c29 100644
--- a/src/x64/code-stubs-x64.cc
+++ b/src/x64/code-stubs-x64.cc
@@ -2228,16 +2228,17 @@ static void EmitWrapCase(MacroAssembler* masm,
 }
 
 
-void CallFunctionStub::Generate(MacroAssembler* masm) {
+static void CallFunctionNoFeedback(MacroAssembler* masm,
+                                   int argc, bool needs_checks,
+                                   bool call_as_method) {
   // rdi : the function to call
 
   // wrap_and_call can only be true if we are compiling a monomorphic method.
   Isolate* isolate = masm->isolate();
   Label slow, non_function, wrap, cont;
-  int argc = argc_;
   StackArgumentsAccessor args(rsp, argc);
 
-  if (NeedsChecks()) {
+  if (needs_checks) {
     // Check that the function really is a JavaScript function.
     __ JumpIfSmi(rdi, &non_function);
 
@@ -2249,15 +2250,15 @@ void CallFunctionStub::Generate(MacroAssembler* masm) {
   // Fast-case: Just invoke the function.
   ParameterCount actual(argc);
 
-  if (CallAsMethod()) {
-    if (NeedsChecks()) {
+  if (call_as_method) {
+    if (needs_checks) {
       EmitContinueIfStrictOrNative(masm, &cont);
     }
 
     // Load the receiver from the stack.
     __ movp(rax, args.GetReceiverOperand());
 
-    if (NeedsChecks()) {
+    if (needs_checks) {
       __ JumpIfSmi(rax, &wrap);
 
       __ CmpObjectType(rax, FIRST_SPEC_OBJECT_TYPE, rcx);
@@ -2271,19 +2272,24 @@ void CallFunctionStub::Generate(MacroAssembler* masm) {
 
   __ InvokeFunction(rdi, actual, JUMP_FUNCTION, NullCallWrapper());
 
-  if (NeedsChecks()) {
+  if (needs_checks) {
     // Slow-case: Non-function called.
     __ bind(&slow);
     EmitSlowCase(isolate, masm, &args, argc, &non_function);
   }
 
-  if (CallAsMethod()) {
+  if (call_as_method) {
     __ bind(&wrap);
     EmitWrapCase(masm, &args, &cont);
   }
 }
 
 
+void CallFunctionStub::Generate(MacroAssembler* masm) {
+  CallFunctionNoFeedback(masm, argc_, NeedsChecks(), CallAsMethod());
+}
+
+
 void CallConstructStub::Generate(MacroAssembler* masm) {
   // rax : number of arguments
   // rbx : feedback vector
@@ -2358,6 +2364,52 @@ static void EmitLoadTypeFeedbackVector(MacroAssembler* masm, Register vector) {
 }
 
 
+void CallICStub::Generate_MonomorphicArray(MacroAssembler* masm, Label* miss) {
+  // rdi - function
+  // rbx - feedback vector
+  // rdx - slot id
+  __ LoadGlobalFunction(Context::ARRAY_FUNCTION_INDEX, rcx);
+  __ cmpq(rdi, rcx);
+  __ j(not_equal, miss);
+
+  __ movq(rax, Immediate(arg_count()));
+  __ movp(rbx, FieldOperand(rbx, rdx, times_pointer_size,
+                            FixedArray::kHeaderSize));
+
+  // Verify that ecx contains an AllocationSite
+  __ AssertUndefinedOrAllocationSite(rbx);
+  ArrayConstructorStub stub(masm->isolate(), arg_count());
+  __ TailCallStub(&stub);
+}
+
+
+void CallICStub::Generate_CustomFeedbackCall(MacroAssembler* masm) {
+  // rdi - function
+  // rbx - feedback vector
+  // rdx - slot id
+  Label miss;
+
+  if (state_.stub_type() == CallIC::MONOMORPHIC_ARRAY) {
+    Generate_MonomorphicArray(masm, &miss);
+  } else {
+    // So far there is only one customer for our custom feedback scheme.
+    UNREACHABLE();
+  }
+
+  __ bind(&miss);
+  GenerateMiss(masm);
+
+  // The slow case, we need this no matter what to complete a call after a miss.
+  CallFunctionNoFeedback(masm,
+                         arg_count(),
+                         true,
+                         CallAsMethod());
+
+  // Unreachable.
+  __ int3();
+}
+
+
 void CallICStub::Generate(MacroAssembler* masm) {
   // rdi - function
   // rbx - vector
@@ -2372,6 +2424,12 @@ void CallICStub::Generate(MacroAssembler* masm) {
 
   EmitLoadTypeFeedbackVector(masm, rbx);
 
+  // the MONOMORPHIC_ARRAY case is handled with a helper function.
+  if (state_.stub_type() != CallIC::DEFAULT) {
+    Generate_CustomFeedbackCall(masm);
+    return;
+  }
+
   // The checks. First, does rdi match the recorded monomorphic target?
   __ SmiToInteger32(rdx, rdx);
   __ cmpq(rdi, FieldOperand(rbx, rdx, times_pointer_size,