[builtins] Remove some (now) unused code from C++ builtin adaptor.

src/ppc/builtins-ppc.cc

Index: src/ppc/builtins-ppc.cc
diff --git a/src/ppc/builtins-ppc.cc b/src/ppc/builtins-ppc.cc
index 590a242aee5ff083c1d466e19ccb420baafae008..4e23f38102c9eb4d3702d1d84c2c844678ad64e6 100644
--- a/src/ppc/builtins-ppc.cc
+++ b/src/ppc/builtins-ppc.cc
@@ -21,8 +21,6 @@ void Builtins::Generate_Adaptor(MacroAssembler* masm, CFunctionId id,
                                 BuiltinExtraArguments extra_args) {
   // ----------- S t a t e -------------
   //  -- r3                 : number of arguments excluding receiver
-  //                          (only guaranteed when the called function
-  //                           is not marked as DontAdaptArguments)
   //  -- r4                 : called function
   //  -- sp[0]              : last argument
   //  -- ...
@@ -31,13 +29,6 @@ void Builtins::Generate_Adaptor(MacroAssembler* masm, CFunctionId id,
   // -----------------------------------
   __ AssertFunction(r4);
 
-  // Make sure we operate in the context of the called function (for example
-  // ConstructStubs implemented in C++ will be run in the context of the caller
-  // instead of the callee, due to the way that [[Construct]] is defined for
-  // ordinary functions).
-  // TODO(bmeurer): Can we make this more robust?
-  __ LoadP(cp, FieldMemOperand(r4, JSFunction::kContextOffset));
-
   // Insert extra arguments.
   int num_extra_args = 0;
   if (extra_args == NEEDS_CALLED_FUNCTION) {
@@ -48,24 +39,7 @@ void Builtins::Generate_Adaptor(MacroAssembler* masm, CFunctionId id,
   }
 
   // JumpToExternalReference expects r3 to contain the number of arguments
-  // including the receiver and the extra arguments.  But r3 is only valid
-  // if the called function is marked as DontAdaptArguments, otherwise we
-  // need to load the argument count from the SharedFunctionInfo.
-  __ LoadP(r5, FieldMemOperand(r4, JSFunction::kSharedFunctionInfoOffset));
-  __ LoadWordArith(
-      r5, FieldMemOperand(r5, SharedFunctionInfo::kFormalParameterCountOffset));
-#if !V8_TARGET_ARCH_PPC64
-  __ SmiUntag(r5);
-#endif
-  __ cmpi(r5, Operand(SharedFunctionInfo::kDontAdaptArgumentsSentinel));
-  if (CpuFeatures::IsSupported(ISELECT)) {
-    __ isel(ne, r3, r5, r3);
-  } else {
-    Label skip;
-    __ beq(&skip);
-    __ mr(r3, r5);
-    __ bind(&skip);
-  }
+  // including the receiver and the extra arguments.
   __ addi(r3, r3, Operand(num_extra_args + 1));
 
   __ JumpToExternalReference(ExternalReference(id, masm->isolate()));