Skip the CallFunctionStub when the callee function can be statically determined.

src/compiler/linkage.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/code-stubs.h"
 #include "src/compiler.h"
 #include "src/compiler/linkage.h"
 #include "src/compiler/node.h"
 #include "src/compiler/pipeline.h"
 #include "src/scopes.h"
@@ skipping 24 matching lines @@
   return os << d.kind() << ":" << d.debug_name() << ":r" << d.ReturnCount()
             << "j" << d.JSParameterCount() << "i" << d.InputCount() << "f"
             << d.FrameStateCount();
 }
 
 
 CallDescriptor* Linkage::ComputeIncoming(Zone* zone, CompilationInfo* info) {
   if (info->function() != NULL) {
     // If we already have the function literal, use the number of parameters
     // plus the receiver.
-    return GetJSCallDescriptor(1 + info->function()->parameter_count(), zone);
+    return GetJSCallDescriptor(1 + info->function()->parameter_count(), zone,
+                               CallDescriptor::kNoFlags);
   }
   if (!info->closure().is_null()) {
     // If we are compiling a JS function, use a JS call descriptor,
     // plus the receiver.
     SharedFunctionInfo* shared = info->closure()->shared();
-    return GetJSCallDescriptor(1 + shared->formal_parameter_count(), zone);
+    return GetJSCallDescriptor(1 + shared->formal_parameter_count(), zone,
+                               CallDescriptor::kNoFlags);
   }
   if (info->code_stub() != NULL) {
     // Use the code stub interface descriptor.
     CallInterfaceDescriptor descriptor =
         info->code_stub()->GetCallInterfaceDescriptor();
     return GetStubCallDescriptor(descriptor, 0, CallDescriptor::kNoFlags, zone);
   }
   return NULL;  // TODO(titzer): ?
 }
 
@@ skipping 19 matching lines @@
     // No frame. Retrieve all parameters relative to stack pointer.
     DCHECK(spill_slot < 0);  // Must be a parameter.
     int register_save_area_size = frame->GetRegisterSaveAreaSize();
     int offset = register_save_area_size - (spill_slot + 1) * kPointerSize +
                  kPCOnStackSize + extra;
     return FrameOffset::FromStackPointer(offset);
   }
 }
 
 
-CallDescriptor* Linkage::GetJSCallDescriptor(int parameter_count) const {
-  return GetJSCallDescriptor(parameter_count, zone_);
+CallDescriptor* Linkage::GetJSCallDescriptor(
+    int parameter_count, CallDescriptor::Flags flags) const {
+  return GetJSCallDescriptor(parameter_count, zone_, flags);
 }
 
 
 CallDescriptor* Linkage::GetRuntimeCallDescriptor(
     Runtime::FunctionId function, int parameter_count,
     Operator::Properties properties) const {
   return GetRuntimeCallDescriptor(function, parameter_count, properties, zone_);
 }
 
 
@@ skipping 138 matching lines @@
 
 CallDescriptor* Linkage::GetSimplifiedCDescriptor(Zone* zone,
                                                   MachineSignature* sig) {
   UNIMPLEMENTED();
   return NULL;
 }
 #endif  // !V8_TURBOFAN_BACKEND
 }
 }
 }  // namespace v8::internal::compiler