PPC: Handle StepIn for constructors through PrepareStep just like for regular calls

Port 14ec485c

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

Review URL: https://codereview.chromium.org/1455563005

Cr-Commit-Position: refs/heads/master@{#32060}

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

@@ -3054,7 +3054,7 @@ void FullCodeGenerator::VisitCallNew(CallNew* expr) {
 
   // Call the construct call builtin that handles allocation and
   // constructor invocation.
-  SetConstructCallPosition(expr);
+  SetConstructCallPosition(expr, arg_count);
 
   // Load function and argument count into r4 and r3.
   __ mov(r3, Operand(arg_count));
@@ -3090,7 +3090,7 @@ void FullCodeGenerator::EmitSuperConstructorCall(Call* expr) {
 
   // Call the construct call builtin that handles allocation and
   // constructor invocation.
-  SetConstructCallPosition(expr);
+  SetConstructCallPosition(expr, arg_count);
 
   // Load new target into r7.
   VisitForAccumulatorValue(super_call_ref->new_target_var());
@@ -3822,21 +3822,23 @@ void FullCodeGenerator::EmitDefaultConstructorCallSuper(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   DCHECK(args->length() == 2);
 
-  // Evaluate new.target.
+  // Evaluate new.target and super constructor.
   VisitForStackValue(args->at(0));
+  VisitForStackValue(args->at(1));
 
-  // Evaluate super constructor (to stack and r4).
-  VisitForAccumulatorValue(args->at(1));
-  __ push(result_register());
-  __ mr(r4, result_register());
-
-  // Load new target into r6.
-  __ LoadP(r6, MemOperand(sp, 1 * kPointerSize));
+  // Call the construct call builtin that handles allocation and
+  // constructor invocation.
+  SetConstructCallPosition(expr, 0);
 
   // Check if the calling frame is an arguments adaptor frame.
   Label adaptor_frame, args_set_up, runtime;
   __ LoadP(r5, MemOperand(fp, StandardFrameConstants::kCallerFPOffset));
   __ LoadP(r7, MemOperand(r5, StandardFrameConstants::kContextOffset));
+
+  // Load super constructor, new target into r4, r6.
+  __ LoadP(r4, MemOperand(sp));
+  __ LoadP(r6, MemOperand(sp, 1 * kPointerSize));
+
   __ CmpSmiLiteral(r7, Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR), r0);
   __ beq(&adaptor_frame);
 

src/ppc/builtins-ppc.cc

@@ -375,13 +375,6 @@ static void Generate_JSConstructStubHelper(MacroAssembler* masm,
     // the preconditions is not met, the code bails out to the runtime call.
     Label rt_call, allocated;
     if (FLAG_inline_new) {
-      ExternalReference debug_step_in_fp =
-          ExternalReference::debug_step_in_fp_address(isolate);
-      __ mov(r5, Operand(debug_step_in_fp));
-      __ LoadP(r5, MemOperand(r5));
-      __ cmpi(r5, Operand::Zero());
-      __ bne(&rt_call);
-
       // Verify that the new target is a JSFunction.
       __ CompareObjectType(r6, r8, r7, JS_FUNCTION_TYPE);
       __ bne(&rt_call);
@@ -684,21 +677,6 @@ void Builtins::Generate_JSConstructStubForDerived(MacroAssembler* masm) {
     __ bdnz(&loop);
     __ bind(&no_args);
 
-    // Handle step in.
-    Label skip_step_in;
-    ExternalReference debug_step_in_fp =
-        ExternalReference::debug_step_in_fp_address(masm->isolate());
-    __ mov(r5, Operand(debug_step_in_fp));
-    __ LoadP(r5, MemOperand(r5));
-    __ and_(r0, r5, r5, SetRC);
-    __ beq(&skip_step_in, cr0);
-
-    __ Push(r3, r4, r4);
-    __ CallRuntime(Runtime::kHandleStepInForDerivedConstructors, 1);
-    __ Pop(r3, r4);
-
-    __ bind(&skip_step_in);
-
     // Call the function.
     // r3: number of arguments
     // r4: constructor function