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

src/compiler/mips64/code-generator-mips64.cc

Index: src/compiler/mips64/code-generator-mips64.cc
diff --git a/src/compiler/mips64/code-generator-mips64.cc b/src/compiler/mips64/code-generator-mips64.cc
index 373a1a6abce6efacd5e6a6f00d62f25a4723aa65..c1f5148e6701b3332d844eac27458cf4ee0a89e5 100644
--- a/src/compiler/mips64/code-generator-mips64.cc
+++ b/src/compiler/mips64/code-generator-mips64.cc
@@ -501,13 +501,37 @@ void CodeGenerator::AssemblePrepareTailCall(int stack_param_delta) {
   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.
+  __ ld(scratch3, MemOperand(fp, StandardFrameConstants::kContextOffset));
+  __ Branch(&done, ne, scratch3,
+            Operand(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
+
+  // Load arguments count from current arguments adaptor frame (note, it
+  // does not include receiver).
+  Register caller_args_count_reg = scratch1;
+  __ ld(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) {
   MipsOperandConverter i(this, instr);
   InstructionCode opcode = instr->opcode();
-
-  switch (ArchOpcodeField::decode(opcode)) {
+  ArchOpcode arch_opcode = ArchOpcodeField::decode(opcode);
+  switch (arch_opcode) {
     case kArchCallCodeObject: {
       EnsureSpaceForLazyDeopt();
       if (instr->InputAt(0)->IsImmediate()) {
@@ -521,9 +545,15 @@ void CodeGenerator::AssembleArchInstruction(Instruction* instr) {
       frame_access_state()->ClearSPDelta();
       break;
     }
+    case kArchTailCallCodeObjectFromJSFunction:
     case kArchTailCallCodeObject: {
       int stack_param_delta = i.InputInt32(instr->InputCount() - 1);
       AssembleDeconstructActivationRecord(stack_param_delta);
+      if (arch_opcode == kArchTailCallCodeObjectFromJSFunction) {
+        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);
@@ -548,6 +578,7 @@ void CodeGenerator::AssembleArchInstruction(Instruction* instr) {
       frame_access_state()->ClearSPDelta();
       break;
     }
+    case kArchTailCallJSFunctionFromJSFunction:
     case kArchTailCallJSFunction: {
       Register func = i.InputRegister(0);
       if (FLAG_debug_code) {
@@ -557,6 +588,11 @@ void CodeGenerator::AssembleArchInstruction(Instruction* instr) {
       }
       int stack_param_delta = i.InputInt32(instr->InputCount() - 1);
       AssembleDeconstructActivationRecord(stack_param_delta);
+      if (arch_opcode == kArchTailCallJSFunctionFromJSFunction) {
+        AssemblePopArgumentsAdaptorFrame(kJavaScriptCallArgCountRegister,
+                                         i.TempRegister(0), i.TempRegister(1),
+                                         i.TempRegister(2));
+      }
       __ ld(at, FieldMemOperand(func, JSFunction::kCodeEntryOffset));
       __ Jump(at);
       frame_access_state()->ClearSPDelta();