[fullcodegen] Implement control flow across do-expressions.

src/full-codegen/arm64/full-codegen-arm64.cc

 // Copyright 2013 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_ARM64
 
 #include "src/ast/scopes.h"
 #include "src/code-factory.h"
 #include "src/code-stubs.h"
 #include "src/codegen.h"
@@ skipping 979 matching lines @@
 
 void FullCodeGenerator::VisitForInStatement(ForInStatement* stmt) {
   ASM_LOCATION("FullCodeGenerator::VisitForInStatement");
   Comment cmnt(masm_, "[ ForInStatement");
   SetStatementPosition(stmt, SKIP_BREAK);
 
   FeedbackVectorSlot slot = stmt->ForInFeedbackSlot();
 
   // TODO(all): This visitor probably needs better comments and a revisit.
 
-  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(x0, &convert);
   __ JumpIfObjectType(x0, x10, x11, FIRST_JS_RECEIVER_TYPE, &done_convert, ge);
   __ JumpIfRoot(x0, Heap::kNullValueRootIndex, &exit);
   __ JumpIfRoot(x0, Heap::kUndefinedValueRootIndex, &exit);
   __ Bind(&convert);
   ToObjectStub stub(isolate());
@@ skipping 2849 matching lines @@
   VisitForStackValue(expr->expression());
 
   // TODO(jbramley): Tidy this up once the merge is done, using named registers
   // and suchlike. The implementation changes a little by bleeding_edge so I
   // don't want to spend too much time on it now.
 
   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;
 
       __ B(&suspend);
       // TODO(jbramley): This label is bound here because the following code
       // looks at its pos(). Is it possible to do something more efficient here,
       // perhaps using Adr?
       __ 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(x1);
       __ Cmp(x1, Smi::FromInt(JSGeneratorObject::RETURN));
       __ B(ne, &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()));
       __ Mov(x1, Smi::FromInt(continuation.pos()));
       __ Str(x1, FieldMemOperand(x0, JSGeneratorObject::kContinuationOffset));
       __ Str(cp, FieldMemOperand(x0, JSGeneratorObject::kContextOffset));
       __ Mov(x1, cp);
       __ RecordWriteField(x0, JSGeneratorObject::kContextOffset, x1, x2,
                           kLRHasBeenSaved, kDontSaveFPRegs);
       __ Add(x1, fp, StandardFrameConstants::kExpressionsOffset);
       __ Cmp(__ StackPointer(), x1);
       __ B(eq, &post_runtime);
       __ Push(x0);  // generator object
       __ CallRuntime(Runtime::kSuspendJSGeneratorObject, 1);
       __ Ldr(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 137 matching lines @@
   __ Push(Smi::FromInt(JSIteratorResult::kSize));
   __ CallRuntime(Runtime::kAllocateInNewSpace);
 
   __ Bind(&done_allocate);
   Register map_reg = x1;
   Register result_value = x2;
   Register boolean_done = x3;
   Register empty_fixed_array = x4;
   Register untagged_result = x5;
   __ LoadNativeContextSlot(Context::ITERATOR_RESULT_MAP_INDEX, map_reg);
-  __ Pop(result_value);
+  PopOperand(result_value);
   __ LoadRoot(boolean_done,
               done ? Heap::kTrueValueRootIndex : Heap::kFalseValueRootIndex);
   __ LoadRoot(empty_fixed_array, Heap::kEmptyFixedArrayRootIndex);
   STATIC_ASSERT(JSObject::kPropertiesOffset + kPointerSize ==
                 JSObject::kElementsOffset);
   STATIC_ASSERT(JSIteratorResult::kValueOffset + kPointerSize ==
                 JSIteratorResult::kDoneOffset);
   __ ObjectUntag(untagged_result, result);
   __ Str(map_reg, MemOperand(untagged_result, HeapObject::kMapOffset));
   __ Stp(empty_fixed_array, empty_fixed_array,
@@ skipping 211 matching lines @@
   }
 
   return INTERRUPT;
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_ARM64