PPC: [fullcodegen] Implement control flow across do-expressions.

Port ee8108b7

Original commit message:
    This implements proper handling of local control flow (i.e. break and
    continue) that spans the boundary of a do-expression. We can no longer
    determine the number of operands to be dropped from the nesting of
    statements alone, instead we use the new precise operand stack depth
    tracking.

R=mstarzinger@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com
TEST=mjsunit/harmony/do-expressions-control
BUG=v8:4488
LOG=n

Review URL: https://codereview.chromium.org/1735623002

Cr-Commit-Position: refs/heads/master@{#34264}

src/full-codegen/ppc/full-codegen-ppc.cc

@@ -955,14 +955,14 @@ void FullCodeGenerator::VisitForInStatement(ForInStatement* stmt) {
 
   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.
@@ -1825,7 +1825,7 @@ void FullCodeGenerator::VisitYield(Yield* expr) {
     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;
@@ -1844,6 +1844,7 @@ void FullCodeGenerator::VisitYield(Yield* expr) {
       EmitUnwindAndReturn();
 
       __ bind(&suspend);
+      OperandStackDepthIncrement(1);  // Not popped on this path.
       VisitForAccumulatorValue(expr->generator_object());
       DCHECK(continuation.pos() > 0 && Smi::IsValid(continuation.pos()));
       __ LoadSmiLiteral(r4, Smi::FromInt(continuation.pos()));
@@ -1870,7 +1871,6 @@ void FullCodeGenerator::VisitYield(Yield* expr) {
 
     case Yield::kFinal: {
       // Pop value from top-of-stack slot, box result into result register.
-      OperandStackDepthDecrement(1);
       EmitCreateIteratorResult(true);
       EmitUnwindAndReturn();
       break;
@@ -2038,7 +2038,7 @@ void FullCodeGenerator::EmitCreateIteratorResult(bool done) {
 
   __ bind(&done_allocate);
   __ LoadNativeContextSlot(Context::ITERATOR_RESULT_MAP_INDEX, r4);
-  __ pop(r5);
+  PopOperand(r5);
   __ LoadRoot(r6,
               done ? Heap::kTrueValueRootIndex : Heap::kFalseValueRootIndex);
   __ LoadRoot(r7, Heap::kEmptyFixedArrayRootIndex);