PPC: Use register arguments for RestParamAccessStub

Port 82ca2a41

Original commit message:
    This is preferable because in TurboFan we need to call it, and can't pass
    untagged external pointers on the stack.

R=mvstanton@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com
BUG=

Review URL: https://codereview.chromium.org/1553143002

Cr-Commit-Position: refs/heads/master@{#33092}

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

@@ -273,11 +273,15 @@ void FullCodeGenerator::Generate() {
     int num_parameters = info->scope()->num_parameters();
     int offset = num_parameters * kPointerSize;
 
-    __ addi(r6, fp, Operand(StandardFrameConstants::kCallerSPOffset + offset));
-    __ LoadSmiLiteral(r5, Smi::FromInt(num_parameters));
-    __ LoadSmiLiteral(r4, Smi::FromInt(rest_index));
-    __ LoadSmiLiteral(r3, Smi::FromInt(language_mode()));
-    __ Push(r6, r5, r4, r3);
+    __ LoadSmiLiteral(RestParamAccessDescriptor::parameter_count(),
+                      Operand(Smi::FromInt(num_parameters)));
+    __ addi(RestParamAccessDescriptor::parameter_pointer(), fp,
+            Operand(StandardFrameConstants::kCallerSPOffset + offset));
+    __ LoadSmiLiteral(RestParamAccessDescriptor::rest_parameter_index(),
+                      Operand(Smi::FromInt(rest_index)));
+    __ LoadSmiLiteral(RestParamAccessDescriptor::language_mode(),
+                      Operand(Smi::FromInt(language_mode())));
+    DCHECK(r4.is(RestParamAccessDescriptor::language_mode()));
     function_in_register_r4 = false;
 
     RestParamAccessStub stub(isolate());

src/ppc/code-stubs-ppc.cc

@@ -1977,27 +1977,25 @@ void ArgumentsAccessStub::GenerateNewStrict(MacroAssembler* masm) {
 
 
 void RestParamAccessStub::GenerateNew(MacroAssembler* masm) {
-  // Stack layout on entry.
-  //  sp[0] : language mode
-  //  sp[4] : index of rest parameter
-  //  sp[8] : number of parameters
-  //  sp[12] : receiver displacement
+  // r5 : number of parameters (tagged)
+  // r6 : parameters pointer
+  // r7 : rest parameter index (tagged)
+  // r4 : language mode (tagged)
 
   Label runtime;
-  __ LoadP(r5, MemOperand(fp, StandardFrameConstants::kCallerFPOffset));
-  __ LoadP(r6, MemOperand(r5, StandardFrameConstants::kContextOffset));
-  __ CmpSmiLiteral(r6, Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR), r0);
+  __ LoadP(r8, MemOperand(fp, StandardFrameConstants::kCallerFPOffset));
+  __ LoadP(r3, MemOperand(r8, StandardFrameConstants::kContextOffset));
+  __ CmpSmiLiteral(r3, Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR), r0);
   __ bne(&runtime);
 
   // Patch the arguments.length and the parameters pointer.
-  __ LoadP(r4, MemOperand(r5, ArgumentsAdaptorFrameConstants::kLengthOffset));
-  __ StoreP(r4, MemOperand(sp, 2 * kPointerSize));
-  __ SmiToPtrArrayOffset(r0, r4);
-  __ add(r6, r5, r0);
+  __ LoadP(r5, MemOperand(r8, ArgumentsAdaptorFrameConstants::kLengthOffset));
+  __ SmiToPtrArrayOffset(r0, r5);
+  __ add(r6, r8, r0);
   __ addi(r6, r6, Operand(StandardFrameConstants::kCallerSPOffset));
-  __ StoreP(r6, MemOperand(sp, 3 * kPointerSize));
 
   __ bind(&runtime);
+  __ Push(r5, r6, r7, r4);
   __ TailCallRuntime(Runtime::kNewRestParam);
 }
 

src/ppc/interface-descriptors-ppc.cc

@@ -63,6 +63,12 @@ const Register ArgumentsAccessNewDescriptor::parameter_count() { return r5; }
 const Register ArgumentsAccessNewDescriptor::parameter_pointer() { return r6; }
 
 
+const Register RestParamAccessDescriptor::parameter_count() { return r5; }
+const Register RestParamAccessDescriptor::parameter_pointer() { return r6; }
+const Register RestParamAccessDescriptor::rest_parameter_index() { return r7; }
+const Register RestParamAccessDescriptor::language_mode() { return r4; }
+
+
 const Register ApiGetterDescriptor::function_address() { return r5; }