PPC: [turbofan] Further fixing ES6 tail call elimination in Turbofan.

src/compiler/ppc/code-generator-ppc.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/compiler/code-generator.h"
 
 #include "src/ast/scopes.h"
 #include "src/compiler/code-generator-impl.h"
 #include "src/compiler/gap-resolver.h"
 #include "src/compiler/node-matchers.h"
@@ skipping 667 matching lines @@
   if (sp_slot_delta < 0) {
     __ Add(sp, sp, sp_slot_delta * kPointerSize, r0);
     frame_access_state()->IncreaseSPDelta(-sp_slot_delta);
   }
   if (frame()->needs_frame()) {
     __ RestoreFrameStateForTailCall();
   }
   frame_access_state()->SetFrameAccessToSP();
 }
 
+void CodeGenerator::AssemblePopArgumentsAdaptorFrame(Register args_reg,
+                                                     Register scratch1,
+                                                     Register scratch2,
+                                                     Register scratch3) {
+  DCHECK(!AreAliased(args_reg, scratch1, scratch2, scratch3));
+  Label done;
+
+  // Check if current frame is an arguments adaptor frame.
+  __ LoadP(scratch1, MemOperand(fp, StandardFrameConstants::kContextOffset));
+  __ CmpSmiLiteral(scratch1, Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR), r0);
+  __ bne(&done);
+
+  // Load arguments count from current arguments adaptor frame (note, it
+  // does not include receiver).
+  Register caller_args_count_reg = scratch1;
+  __ LoadP(caller_args_count_reg,
+           MemOperand(fp, ArgumentsAdaptorFrameConstants::kLengthOffset));
+  __ SmiUntag(caller_args_count_reg);
+
+  ParameterCount callee_args_count(args_reg);
+  __ PrepareForTailCall(callee_args_count, caller_args_count_reg, scratch2,
+                        scratch3);
+  __ bind(&done);
+}
 
 // Assembles an instruction after register allocation, producing machine code.
 void CodeGenerator::AssembleArchInstruction(Instruction* instr) {
   PPCOperandConverter i(this, instr);
   ArchOpcode opcode = ArchOpcodeField::decode(instr->opcode());
 
   switch (opcode) {
     case kArchCallCodeObject: {
       v8::internal::Assembler::BlockTrampolinePoolScope block_trampoline_pool(
           masm());
       EnsureSpaceForLazyDeopt();
       if (HasRegisterInput(instr, 0)) {
         __ addi(ip, i.InputRegister(0),
                 Operand(Code::kHeaderSize - kHeapObjectTag));
         __ Call(ip);
       } else {
         __ Call(Handle<Code>::cast(i.InputHeapObject(0)),
                 RelocInfo::CODE_TARGET);
       }
       RecordCallPosition(instr);
       DCHECK_EQ(LeaveRC, i.OutputRCBit());
       frame_access_state()->ClearSPDelta();
       break;
     }
+    case kArchTailCallCodeObjectFromJSFunction:
     case kArchTailCallCodeObject: {
       int stack_param_delta = i.InputInt32(instr->InputCount() - 1);
       AssembleDeconstructActivationRecord(stack_param_delta);
+      if (opcode == kArchTailCallCodeObjectFromJSFunction) {
+        AssemblePopArgumentsAdaptorFrame(kJavaScriptCallArgCountRegister,
+                                         i.TempRegister(0), i.TempRegister(1),
+                                         i.TempRegister(2));
+      }
       if (HasRegisterInput(instr, 0)) {
         __ addi(ip, i.InputRegister(0),
                 Operand(Code::kHeaderSize - kHeapObjectTag));
         __ Jump(ip);
       } else {
         // We cannot use the constant pool to load the target since
         // we've already restored the caller's frame.
         ConstantPoolUnavailableScope constant_pool_unavailable(masm());
         __ Jump(Handle<Code>::cast(i.InputHeapObject(0)),
                 RelocInfo::CODE_TARGET);
@@ skipping 14 matching lines @@
         __ cmp(cp, kScratchReg);
         __ Assert(eq, kWrongFunctionContext);
       }
       __ LoadP(ip, FieldMemOperand(func, JSFunction::kCodeEntryOffset));
       __ Call(ip);
       RecordCallPosition(instr);
       DCHECK_EQ(LeaveRC, i.OutputRCBit());
       frame_access_state()->ClearSPDelta();
       break;
     }
+    case kArchTailCallJSFunctionFromJSFunction:
     case kArchTailCallJSFunction: {
       Register func = i.InputRegister(0);
       if (FLAG_debug_code) {
         // Check the function's context matches the context argument.
         __ LoadP(kScratchReg,
                  FieldMemOperand(func, JSFunction::kContextOffset));
         __ cmp(cp, kScratchReg);
         __ Assert(eq, kWrongFunctionContext);
       }
       int stack_param_delta = i.InputInt32(instr->InputCount() - 1);
       AssembleDeconstructActivationRecord(stack_param_delta);
+      if (opcode == kArchTailCallJSFunctionFromJSFunction) {
+        AssemblePopArgumentsAdaptorFrame(kJavaScriptCallArgCountRegister,
+                                         i.TempRegister(0), i.TempRegister(1),
+                                         i.TempRegister(2));
+      }
       __ LoadP(ip, FieldMemOperand(func, JSFunction::kCodeEntryOffset));
       __ Jump(ip);
       DCHECK_EQ(LeaveRC, i.OutputRCBit());
       frame_access_state()->ClearSPDelta();
       break;
     }
     case kArchPrepareCallCFunction: {
       int const num_parameters = MiscField::decode(instr->opcode());
       __ PrepareCallCFunction(num_parameters, kScratchReg);
       // Frame alignment requires using FP-relative frame addressing.
@@ skipping 1141 matching lines @@
       padding_size -= v8::internal::Assembler::kInstrSize;
     }
   }
 }
 
 #undef __
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8