[csa] Add CSA::CallBuiltin and Builtins::CallableFor

src/builtins/builtins.cc

 // Copyright 2012 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/builtins/builtins.h"
 #include "src/api.h"
 #include "src/assembler-inl.h"
+#include "src/callable.h"
 #include "src/code-events.h"
 #include "src/compiler/code-assembler.h"
 #include "src/ic/ic-state.h"
 #include "src/interface-descriptors.h"
 #include "src/isolate.h"
 #include "src/macro-assembler.h"
 #include "src/objects-inl.h"
 
 namespace v8 {
 namespace internal {
@@ skipping 250 matching lines @@
     case OrdinaryToPrimitiveHint::kNumber:
       return OrdinaryToPrimitive_Number();
     case OrdinaryToPrimitiveHint::kString:
       return OrdinaryToPrimitive_String();
   }
   UNREACHABLE();
   return Handle<Code>::null();
 }
 
 // static
+Callable Builtins::CallableFor(Isolate* isolate, Name name) {
+  switch (name) {
+#define CASE(Name, _, __, InterfaceDescriptor, ...)                      \
+  case k##Name: {                                                        \
+    Handle<Code> code(Code::cast(isolate->builtins()->builtins_[name])); \

[caitp, 2017/03/16 13:30:06]

Is there any way we could push args in excess of 4 to the stack? It would be
helpful for moving InternelPerformPromiseThen to a stub without doing extra type
checks and loads.

+    auto descriptor = InterfaceDescriptor##Descriptor(isolate);          \
+    return Callable(code, descriptor);                                   \
+  }
+    BUILTIN_LIST_TFS(CASE)
+#undef CASE
+    default:
+      UNREACHABLE();
+      return Callable(Handle<Code>::null(), VoidDescriptor(isolate));
+  }
+}
+
+// static
 const char* Builtins::name(int index) {
   switch (index) {
 #define CASE(Name, ...) \
   case k##Name:         \
     return #Name;
     BUILTIN_LIST_ALL(CASE)
 #undef CASE
     default:
       UNREACHABLE();
       break;
@@ skipping 88 matching lines @@
   // TODO(jochen): Remove this.
   if (responsible_context.is_null()) {
     return true;
   }
   if (*responsible_context == target->context()) return true;
   return isolate->MayAccess(responsible_context, target_global_proxy);
 }
 
 }  // namespace internal
 }  // namespace v8