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

src/compiler/arm64/code-generator-arm64.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/arm64/frames-arm64.h"
 #include "src/arm64/macro-assembler-arm64.h"
 #include "src/ast/scopes.h"
 #include "src/compiler/code-generator-impl.h"
@@ skipping 471 matching lines @@
     __ Claim(-sp_slot_delta);
     frame_access_state()->IncreaseSPDelta(-sp_slot_delta);
   }
   if (frame()->needs_frame()) {
     __ Ldr(lr, MemOperand(fp, StandardFrameConstants::kCallerPCOffset));
     __ Ldr(fp, MemOperand(fp, StandardFrameConstants::kCallerFPOffset));
   }
   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.
+  __ Ldr(scratch1, MemOperand(fp, StandardFrameConstants::kContextOffset));
+  __ Cmp(scratch1, Operand(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
+  __ B(ne, &done);
+
+  // Load arguments count from current arguments adaptor frame (note, it
+  // does not include receiver).
+  Register caller_args_count_reg = scratch1;
+  __ Ldr(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) {
   Arm64OperandConverter i(this, instr);
   InstructionCode opcode = instr->opcode();
   ArchOpcode arch_opcode = ArchOpcodeField::decode(opcode);
   switch (arch_opcode) {
     case kArchCallCodeObject: {
       EnsureSpaceForLazyDeopt();
       if (instr->InputAt(0)->IsImmediate()) {
         __ Call(Handle<Code>::cast(i.InputHeapObject(0)),
                 RelocInfo::CODE_TARGET);
       } else {
         Register target = i.InputRegister(0);
         __ Add(target, target, Code::kHeaderSize - kHeapObjectTag);
         __ Call(target);
       }
       // TODO(titzer): this is ugly. JSSP should be a caller-save register
       // in this case, but it is not possible to express in the register
       // allocator.
       CallDescriptor::Flags flags =
           static_cast<CallDescriptor::Flags>(MiscField::decode(opcode));
       if (flags & CallDescriptor::kRestoreJSSP) {
         __ mov(jssp, csp);
       }
       frame_access_state()->ClearSPDelta();
       RecordCallPosition(instr);
       break;
     }
+    case kArchTailCallCodeObjectFromJSFunction: {
+      int stack_param_delta = i.InputInt32(instr->InputCount() - 1);
+      AssembleDeconstructActivationRecord(stack_param_delta);
+      AssemblePopArgumentsAdaptorFrame(kJavaScriptCallArgCountRegister,
+                                       i.TempRegister(0), i.TempRegister(1),
+                                       i.TempRegister(2));
+      if (instr->InputAt(0)->IsImmediate()) {
+        __ Jump(Handle<Code>::cast(i.InputHeapObject(0)),
+                RelocInfo::CODE_TARGET);
+      } else {
+        Register target = i.InputRegister(0);
+        __ Add(target, target, Code::kHeaderSize - kHeapObjectTag);
+        __ Jump(target);
+      }
+      frame_access_state()->ClearSPDelta();
+      break;
+    }
     case kArchTailCallCodeObject: {
       int stack_param_delta = i.InputInt32(instr->InputCount() - 1);
       AssembleDeconstructActivationRecord(stack_param_delta);
       if (instr->InputAt(0)->IsImmediate()) {
         __ Jump(Handle<Code>::cast(i.InputHeapObject(0)),
                 RelocInfo::CODE_TARGET);
       } else {
         Register target = i.InputRegister(0);
         __ Add(target, target, Code::kHeaderSize - kHeapObjectTag);
         __ Jump(target);
@@ skipping 19 matching lines @@
       // allocator.
       CallDescriptor::Flags flags =
           static_cast<CallDescriptor::Flags>(MiscField::decode(opcode));
       if (flags & CallDescriptor::kRestoreJSSP) {
         __ mov(jssp, csp);
       }
       frame_access_state()->ClearSPDelta();
       RecordCallPosition(instr);
       break;
     }
+    case kArchTailCallJSFunctionFromJSFunction: {
+      Register func = i.InputRegister(0);
+      if (FLAG_debug_code) {
+        // Check the function's context matches the context argument.
+        UseScratchRegisterScope scope(masm());
+        Register temp = scope.AcquireX();
+        __ Ldr(temp, FieldMemOperand(func, JSFunction::kContextOffset));
+        __ cmp(cp, temp);
+        __ Assert(eq, kWrongFunctionContext);
+      }
+      int stack_param_delta = i.InputInt32(instr->InputCount() - 1);
+      AssembleDeconstructActivationRecord(stack_param_delta);
+      AssemblePopArgumentsAdaptorFrame(kJavaScriptCallArgCountRegister,
+                                       i.TempRegister(0), i.TempRegister(1),
+                                       i.TempRegister(2));
+      __ Ldr(x10, FieldMemOperand(func, JSFunction::kCodeEntryOffset));
+      __ Jump(x10);
+      frame_access_state()->ClearSPDelta();
+      break;
+    }
     case kArchTailCallJSFunction: {
       Register func = i.InputRegister(0);
       if (FLAG_debug_code) {
         // Check the function's context matches the context argument.
         UseScratchRegisterScope scope(masm());
         Register temp = scope.AcquireX();
         __ Ldr(temp, FieldMemOperand(func, JSFunction::kContextOffset));
         __ cmp(cp, temp);
         __ Assert(eq, kWrongFunctionContext);
       }
@@ skipping 1159 matching lines @@
       padding_size -= kInstructionSize;
     }
   }
 }
 
 #undef __
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8