Encapsulate megamorphic load/tail-call in hydrogen

src/arm/lithium-codegen-arm.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/v8.h"
 
 #include "src/arm/lithium-codegen-arm.h"
 #include "src/arm/lithium-gap-resolver-arm.h"
 #include "src/base/bits.h"
 #include "src/code-stubs.h"
 #include "src/hydrogen-osr.h"
+#include "src/ic/stub-cache.h"
 
 namespace v8 {
 namespace internal {
 
 
 class SafepointGenerator FINAL : public CallWrapper {
  public:
   SafepointGenerator(LCodeGen* codegen,
                      LPointerMap* pointers,
                      Safepoint::DeoptMode mode)
@@ skipping 3940 matching lines @@
   } else {
     CallKnownFunction(known_function,
                       instr->hydrogen()->formal_parameter_count(),
                       instr->arity(),
                       instr,
                       R1_CONTAINS_TARGET);
   }
 }
 
 
+void LCodeGen::DoTailCallThroughMegamorphicCache(
+    LTailCallThroughMegamorphicCache* instr) {
+  Register receiver = ToRegister(instr->receiver());
+  Register name = ToRegister(instr->name());
+  DCHECK(receiver.is(LoadDescriptor::ReceiverRegister()));
+  DCHECK(name.is(LoadDescriptor::NameRegister()));
+  DCHECK(receiver.is(r1));
+  DCHECK(name.is(r2));
+
+  Register scratch = r3;
+  Register extra = r4;
+  Register extra2 = r5;
+  Register extra3 = r6;
+
+  // Important for the tail-call.
+  bool must_teardown_frame = NeedsEagerFrame();
+
+  // The probe will tail call to a handler if found.
+  isolate()->stub_cache()->GenerateProbe(masm(), instr->hydrogen()->flags(),
+                                         must_teardown_frame, receiver, name,
+                                         scratch, extra, extra2, extra3);
+
+  // Tail call to miss if we ended up here.
+  if (must_teardown_frame) __ LeaveFrame(StackFrame::INTERNAL);
+  LoadIC::GenerateMiss(masm());
+}
+
+
 void LCodeGen::DoCallWithDescriptor(LCallWithDescriptor* instr) {
   DCHECK(ToRegister(instr->result()).is(r0));
 
   LPointerMap* pointers = instr->pointer_map();
   SafepointGenerator generator(this, pointers, Safepoint::kLazyDeopt);
 
   if (instr->target()->IsConstantOperand()) {
     LConstantOperand* target = LConstantOperand::cast(instr->target());
     Handle<Code> code = Handle<Code>::cast(ToHandle(target));
     generator.BeforeCall(__ CallSize(code, RelocInfo::CODE_TARGET));
@@ skipping 1898 matching lines @@
   __ Push(scope_info);
   __ push(ToRegister(instr->function()));
   CallRuntime(Runtime::kPushBlockContext, 2, instr);
   RecordSafepoint(Safepoint::kNoLazyDeopt);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal