[fullcodegen] Implement control flow across do-expressions.

src/full-codegen/x64/full-codegen-x64.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.
 
 #if V8_TARGET_ARCH_X64
 
 #include "src/ast/scopes.h"
 #include "src/code-factory.h"
 #include "src/code-stubs.h"
 #include "src/codegen.h"
@@ skipping 929 matching lines @@
   PrepareForBailoutForId(stmt->ExitId(), NO_REGISTERS);
 }
 
 
 void FullCodeGenerator::VisitForInStatement(ForInStatement* stmt) {
   Comment cmnt(masm_, "[ ForInStatement");
   SetStatementPosition(stmt, SKIP_BREAK);
 
   FeedbackVectorSlot slot = stmt->ForInFeedbackSlot();
 
-  Label loop, exit;
-  ForIn loop_statement(this, stmt);
-  increment_loop_depth();
-
   // Get the object to enumerate over.
   SetExpressionAsStatementPosition(stmt->enumerable());
   VisitForAccumulatorValue(stmt->enumerable());
-  OperandStackDepthIncrement(ForIn::kElementCount);
+  OperandStackDepthIncrement(5);
+
+  Label loop, exit;
+  Iteration loop_statement(this, stmt);
+  increment_loop_depth();
 
   // If the object is null or undefined, skip over the loop, otherwise convert
   // it to a JS receiver.  See ECMA-262 version 5, section 12.6.4.
   Label convert, done_convert;
   __ JumpIfSmi(rax, &convert, Label::kNear);
   __ CmpObjectType(rax, FIRST_JS_RECEIVER_TYPE, rcx);
   __ j(above_equal, &done_convert, Label::kNear);
   __ CompareRoot(rax, Heap::kNullValueRootIndex);
   __ j(equal, &exit);
   __ CompareRoot(rax, Heap::kUndefinedValueRootIndex);
@@ skipping 140 matching lines @@
   // Generate code for going to the next element by incrementing the
   // index (smi) stored on top of the stack.
   __ bind(loop_statement.continue_label());
   __ SmiAddConstant(Operand(rsp, 0 * kPointerSize), Smi::FromInt(1));
 
   EmitBackEdgeBookkeeping(stmt, &loop);
   __ jmp(&loop);
 
   // Remove the pointers stored on the stack.
   __ bind(loop_statement.break_label());
-  __ addp(rsp, Immediate(5 * kPointerSize));
-  OperandStackDepthDecrement(ForIn::kElementCount);
+  DropOperands(5);
 
   // Exit and decrement the loop depth.
   PrepareForBailoutForId(stmt->ExitId(), NO_REGISTERS);
   __ bind(&exit);
   decrement_loop_depth();
 }
 
 
 void FullCodeGenerator::EmitNewClosure(Handle<SharedFunctionInfo> info,
                                        bool pretenure) {
@@ skipping 691 matching lines @@
   SetExpressionPosition(expr);
 
   // Evaluate yielded value first; the initial iterator definition depends on
   // this.  It stays on the stack while we update the iterator.
   VisitForStackValue(expr->expression());
 
   switch (expr->yield_kind()) {
     case Yield::kSuspend:
       // Pop value from top-of-stack slot; box result into result register.
       EmitCreateIteratorResult(false);
-      __ Push(result_register());
+      PushOperand(result_register());
       // Fall through.
     case Yield::kInitial: {
       Label suspend, continuation, post_runtime, resume;
 
       __ jmp(&suspend);
       __ bind(&continuation);
       // When we arrive here, the stack top is the resume mode and
       // result_register() holds the input value (the argument given to the
       // respective resume operation).
       __ RecordGeneratorContinuation();
       __ Pop(rbx);
       __ SmiCompare(rbx, Smi::FromInt(JSGeneratorObject::RETURN));
       __ j(not_equal, &resume);
       __ Push(result_register());
       EmitCreateIteratorResult(true);
       EmitUnwindAndReturn();
 
       __ bind(&suspend);
+      OperandStackDepthIncrement(1);  // Not popped on this path.
       VisitForAccumulatorValue(expr->generator_object());
       DCHECK(continuation.pos() > 0 && Smi::IsValid(continuation.pos()));
       __ Move(FieldOperand(rax, JSGeneratorObject::kContinuationOffset),
               Smi::FromInt(continuation.pos()));
       __ movp(FieldOperand(rax, JSGeneratorObject::kContextOffset), rsi);
       __ movp(rcx, rsi);
       __ RecordWriteField(rax, JSGeneratorObject::kContextOffset, rcx, rdx,
                           kDontSaveFPRegs);
       __ leap(rbx, Operand(rbp, StandardFrameConstants::kExpressionsOffset));
       __ cmpp(rsp, rbx);
       __ j(equal, &post_runtime);
       __ Push(rax);  // generator object
       __ CallRuntime(Runtime::kSuspendJSGeneratorObject, 1);
       __ movp(context_register(),
               Operand(rbp, StandardFrameConstants::kContextOffset));
       __ bind(&post_runtime);
 
       PopOperand(result_register());
       EmitReturnSequence();
 
       __ bind(&resume);
       context()->Plug(result_register());
       break;
     }
 
     case Yield::kFinal: {
       // Pop value from top-of-stack slot, box result into result register.
-      OperandStackDepthDecrement(1);
       EmitCreateIteratorResult(true);
       EmitUnwindAndReturn();
       break;
     }
 
     case Yield::kDelegating:
       UNREACHABLE();
   }
 }
 
@@ skipping 119 matching lines @@
   __ bind(&done_allocate);
   __ LoadNativeContextSlot(Context::ITERATOR_RESULT_MAP_INDEX, rbx);
   __ movp(FieldOperand(rax, HeapObject::kMapOffset), rbx);
   __ LoadRoot(rbx, Heap::kEmptyFixedArrayRootIndex);
   __ movp(FieldOperand(rax, JSObject::kPropertiesOffset), rbx);
   __ movp(FieldOperand(rax, JSObject::kElementsOffset), rbx);
   __ Pop(FieldOperand(rax, JSIteratorResult::kValueOffset));
   __ LoadRoot(FieldOperand(rax, JSIteratorResult::kDoneOffset),
               done ? Heap::kTrueValueRootIndex : Heap::kFalseValueRootIndex);
   STATIC_ASSERT(JSIteratorResult::kSize == 5 * kPointerSize);
+  OperandStackDepthDecrement(1);
 }
 
 
 void FullCodeGenerator::EmitNamedPropertyLoad(Property* prop) {
   SetExpressionPosition(prop);
   Literal* key = prop->key()->AsLiteral();
   DCHECK(!key->value()->IsSmi());
   DCHECK(!prop->IsSuperAccess());
 
   __ Move(LoadDescriptor::NameRegister(), key->value());
@@ skipping 2093 matching lines @@
   DCHECK_EQ(isolate->builtins()->OsrAfterStackCheck()->entry(),
             Assembler::target_address_at(call_target_address,
                                          unoptimized_code));
   return OSR_AFTER_STACK_CHECK;
 }
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X64