PPC: use Cmpi to handle case when kMaxRegularHeapObjectSize > 16bits

R=joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com, mbrandy@us.ibm.com

BUG=
LOG=N

Review-Url: https://codereview.chromium.org/2069363002
Cr-Commit-Position: refs/heads/master@{#37022}

src/ppc/code-stubs-ppc.cc

@@ -4695,7 +4695,7 @@ void FastNewRestParameterStub::Generate(MacroAssembler* masm) {
     // Fall back to %AllocateInNewSpace (if not too big).
     Label too_big_for_new_space;
     __ bind(&allocate);
-    __ cmpi(r10, Operand(Page::kMaxRegularHeapObjectSize));
+    __ Cmpi(r10, Operand(Page::kMaxRegularHeapObjectSize), r0);
     __ bgt(&too_big_for_new_space);
     {
       FrameAndConstantPoolScope scope(masm, StackFrame::INTERNAL);
@@ -5086,7 +5086,7 @@ void FastNewStrictArgumentsStub::Generate(MacroAssembler* masm) {
   // Fall back to %AllocateInNewSpace (if not too big).
   Label too_big_for_new_space;
   __ bind(&allocate);
-  __ cmpi(r10, Operand(Page::kMaxRegularHeapObjectSize));
+  __ Cmpi(r10, Operand(Page::kMaxRegularHeapObjectSize), r0);
   __ bgt(&too_big_for_new_space);
   {
     FrameAndConstantPoolScope scope(masm, StackFrame::INTERNAL);