[fullcodegen] Implement control flow across do-expressions.

src/full-codegen/mips/full-codegen-mips.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_MIPS
 
 // Note on Mips implementation:
 //
 // The result_register() for mips is the 'v0' register, which is defined
 // by the ABI to contain function return values. However, the first
@@ skipping 972 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());
   __ mov(a0, result_register());
-  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(a0, &convert);
   __ GetObjectType(a0, a1, a1);
   __ Branch(USE_DELAY_SLOT, &done_convert, ge, a1,
             Operand(FIRST_JS_RECEIVER_TYPE));
   __ LoadRoot(at, Heap::kNullValueRootIndex);  // In delay slot.
   __ Branch(USE_DELAY_SLOT, &exit, eq, a0, Operand(at));
@@ skipping 867 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(a1);
       __ Branch(&resume, ne, a1,
                 Operand(Smi::FromInt(JSGeneratorObject::RETURN)));
       __ 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()));
       __ li(a1, Operand(Smi::FromInt(continuation.pos())));
       __ sw(a1, FieldMemOperand(v0, JSGeneratorObject::kContinuationOffset));
       __ sw(cp, FieldMemOperand(v0, JSGeneratorObject::kContextOffset));
       __ mov(a1, cp);
       __ RecordWriteField(v0, JSGeneratorObject::kContextOffset, a1, a2,
                           kRAHasBeenSaved, kDontSaveFPRegs);
       __ Addu(a1, fp, Operand(StandardFrameConstants::kExpressionsOffset));
       __ Branch(&post_runtime, eq, sp, Operand(a1));
       __ push(v0);  // generator object
       __ CallRuntime(Runtime::kSuspendJSGeneratorObject, 1);
       __ lw(cp, MemOperand(fp, 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 129 matching lines @@
 
   __ Allocate(JSIteratorResult::kSize, v0, a2, a3, &allocate, TAG_OBJECT);
   __ jmp(&done_allocate);
 
   __ bind(&allocate);
   __ Push(Smi::FromInt(JSIteratorResult::kSize));
   __ CallRuntime(Runtime::kAllocateInNewSpace);
 
   __ bind(&done_allocate);
   __ LoadNativeContextSlot(Context::ITERATOR_RESULT_MAP_INDEX, a1);
-  __ pop(a2);
+  PopOperand(a2);
   __ LoadRoot(a3,
               done ? Heap::kTrueValueRootIndex : Heap::kFalseValueRootIndex);
   __ LoadRoot(t0, Heap::kEmptyFixedArrayRootIndex);
   __ sw(a1, FieldMemOperand(v0, HeapObject::kMapOffset));
   __ sw(t0, FieldMemOperand(v0, JSObject::kPropertiesOffset));
   __ sw(t0, FieldMemOperand(v0, JSObject::kElementsOffset));
   __ sw(a2, FieldMemOperand(v0, JSIteratorResult::kValueOffset));
   __ sw(a3, FieldMemOperand(v0, JSIteratorResult::kDoneOffset));
   STATIC_ASSERT(JSIteratorResult::kSize == 5 * kPointerSize);
 }
@@ skipping 2163 matching lines @@
          reinterpret_cast<uint32_t>(
              isolate->builtins()->OsrAfterStackCheck()->entry()));
   return OSR_AFTER_STACK_CHECK;
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS