Encapsulate megamorphic load/tail-call in hydrogen

src/ia32/lithium-codegen-ia32.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"
 
 #if V8_TARGET_ARCH_IA32
 
 #include "src/base/bits.h"
 #include "src/code-stubs.h"
 #include "src/codegen.h"
 #include "src/deoptimizer.h"
 #include "src/hydrogen-osr.h"
 #include "src/ia32/lithium-codegen-ia32.h"
+#include "src/ic/stub-cache.h"
 
 namespace v8 {
 namespace internal {
 
 // When invoking builtins, we need to record the safepoint in the middle of
 // the invoke instruction sequence generated by the macro assembler.
 class SafepointGenerator FINAL : public CallWrapper {
  public:
   SafepointGenerator(LCodeGen* codegen,
                      LPointerMap* pointers,
@@ skipping 3115 matching lines @@
   XMMRegister result = ToDoubleRegister(instr->result());
   __ movsd(result, double_load_operand);
 }
 
 
 void LCodeGen::DoLoadKeyedFixedArray(LLoadKeyed* instr) {
   Register result = ToRegister(instr->result());
 
   // Load the result.
   __ mov(result,
-         BuildFastArrayOperand(instr->elements(),
-                               instr->key(),
+         BuildFastArrayOperand(instr->elements(), instr->key(),
                                instr->hydrogen()->key()->representation(),
-                               FAST_ELEMENTS,
-                               instr->base_offset()));
+                               FAST_ELEMENTS, instr->base_offset()));
 
   // Check for the hole value.
   if (instr->hydrogen()->RequiresHoleCheck()) {
     if (IsFastSmiElementsKind(instr->hydrogen()->elements_kind())) {
       __ test(result, Immediate(kSmiTagMask));
       DeoptimizeIf(not_equal, instr->environment());
     } else {
       __ cmp(result, factory()->the_hole_value());
       DeoptimizeIf(equal, instr->environment());
     }
@@ skipping 275 matching lines @@
     LPointerMap* pointers = instr->pointer_map();
     SafepointGenerator generator(
         this, pointers, Safepoint::kLazyDeopt);
     ParameterCount count(arity);
     ParameterCount expected(formal_parameter_count);
     __ InvokeFunction(function, expected, count, CALL_FUNCTION, generator);
   }
 }
 
 
+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()));
+
+  Register scratch = ebx;
+  Register extra = eax;
+  DCHECK(!scratch.is(receiver) && !scratch.is(name));
+  DCHECK(!extra.is(receiver) && !extra.is(name));
+
+  // 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);
+
+  // Tail call to miss if we ended up here.
+  if (must_teardown_frame) __ leave();
+  LoadIC::GenerateMiss(masm());
+}
+
+
 void LCodeGen::DoCallWithDescriptor(LCallWithDescriptor* instr) {
   DCHECK(ToRegister(instr->result()).is(eax));
 
   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 2210 matching lines @@
   CallRuntime(Runtime::kPushBlockContext, 2, instr);
   RecordSafepoint(Safepoint::kNoLazyDeopt);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32