[turbofan] Frame elision for code stubs

src/compiler/x64/code-generator-x64.cc

 // Copyright 2013 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 584 matching lines @@
   do {                                                           \
     if (instr->InputAt(4)->IsRegister()) {                       \
       Register value = i.InputRegister(4);                       \
       ASSEMBLE_CHECKED_STORE_INTEGER_IMPL(asm_instr, Register);  \
     } else {                                                     \
       Immediate value = i.InputImmediate(4);                     \
       ASSEMBLE_CHECKED_STORE_INTEGER_IMPL(asm_instr, Immediate); \
     }                                                            \
   } while (false)
 
+void CodeGenerator::AssembleDeconstructFrame() {
+  __ movq(rsp, rbp);
+  __ popq(rbp);
+}
+
+void CodeGenerator::SetupStackPointer() {}
 
 void CodeGenerator::AssembleDeconstructActivationRecord(int stack_param_delta) {
   int sp_slot_delta = TailCallFrameStackSlotDelta(stack_param_delta);
   if (sp_slot_delta > 0) {
     __ addq(rsp, Immediate(sp_slot_delta * kPointerSize));
   }
   frame_access_state()->SetFrameAccessToDefault();
 }
 
 
 void CodeGenerator::AssemblePrepareTailCall(int stack_param_delta) {
   int sp_slot_delta = TailCallFrameStackSlotDelta(stack_param_delta);
   if (sp_slot_delta < 0) {
     __ subq(rsp, Immediate(-sp_slot_delta * kPointerSize));
     frame_access_state()->IncreaseSPDelta(-sp_slot_delta);
   }
-  if (frame()->needs_frame()) {
+  if (frame_access_state()->has_frame()) {
     __ movq(rbp, MemOperand(rbp, 0));
   }
   frame_access_state()->SetFrameAccessToSP();
 }
 
 void CodeGenerator::AssemblePopArgumentsAdaptorFrame(Register args_reg,
                                                      Register scratch1,
                                                      Register scratch2,
                                                      Register scratch3) {
   DCHECK(!AreAliased(args_reg, scratch1, scratch2, scratch3));
@@ skipping 136 matching lines @@
     case kArchRet:
       AssembleReturn();
       break;
     case kArchStackPointer:
       __ movq(i.OutputRegister(), rsp);
       break;
     case kArchFramePointer:
       __ movq(i.OutputRegister(), rbp);
       break;
     case kArchParentFramePointer:
-      if (frame_access_state()->frame()->needs_frame()) {
+      if (frame_access_state()->has_frame()) {
         __ movq(i.OutputRegister(), Operand(rbp, 0));
       } else {
         __ movq(i.OutputRegister(), rbp);
       }
       break;
     case kArchTruncateDoubleToI: {
       auto result = i.OutputRegister();
       auto input = i.InputDoubleRegister(0);
       auto ool = new (zone()) OutOfLineTruncateDoubleToI(this, result, input);
       __ Cvttsd2siq(result, input);
@@ skipping 958 matching lines @@
       break;
     case kX64StackCheck:
       __ CompareRoot(rsp, Heap::kStackLimitRootIndex);
       break;
   }
 }  // NOLINT(readability/fn_size)
 
 
 // Assembles branches after this instruction.
 void CodeGenerator::AssembleArchBranch(Instruction* instr, BranchInfo* branch) {
+  AssembleDeconstructFrameIfNeeded();
   X64OperandConverter i(this, instr);
   Label::Distance flabel_distance =
       branch->fallthru ? Label::kNear : Label::kFar;
   Label* tlabel = branch->true_label;
   Label* flabel = branch->false_label;
   switch (branch->condition) {
     case kUnorderedEqual:
       __ j(parity_even, flabel, flabel_distance);
     // Fall through.
     case kEqual:
@@ skipping 37 matching lines @@
       break;
     default:
       UNREACHABLE();
       break;
   }
   if (!branch->fallthru) __ jmp(flabel, flabel_distance);
 }
 
 
 void CodeGenerator::AssembleArchJump(RpoNumber target) {
+  AssembleDeconstructFrameIfNeeded();
   if (!IsNextInAssemblyOrder(target)) __ jmp(GetLabel(target));
 }
 
 
 // Assembles boolean materializations after this instruction.
 void CodeGenerator::AssembleArchBoolean(Instruction* instr,
                                         FlagsCondition condition) {
   X64OperandConverter i(this, instr);
   Label done;
 
@@ skipping 98 matching lines @@
 
 namespace {
 
 static const int kQuadWordSize = 16;
 
 }  // namespace
 
 
 void CodeGenerator::AssemblePrologue() {
   CallDescriptor* descriptor = linkage()->GetIncomingDescriptor();
-  if (frame()->needs_frame()) {
+  if (frame_access_state()->has_frame()) {
     if (descriptor->IsCFunctionCall()) {
       __ pushq(rbp);
       __ movq(rbp, rsp);
     } else if (descriptor->IsJSFunctionCall()) {
       __ Prologue(this->info()->GeneratePreagedPrologue());
     } else {
       __ StubPrologue(info()->GetOutputStackFrameType());
     }
-  } else {
-    frame()->SetElidedFrameSizeInSlots(kPCOnStackSize / kPointerSize);
   }
-  frame_access_state()->SetFrameAccessToDefault();
-
   int stack_shrink_slots = frame()->GetSpillSlotCount();
   if (info()->is_osr()) {
     // TurboFan OSR-compiled functions cannot be entered directly.
     __ Abort(kShouldNotDirectlyEnterOsrFunction);
 
     // Unoptimized code jumps directly to this entrypoint while the unoptimized
     // frame is still on the stack. Optimized code uses OSR values directly from
     // the unoptimized frame. Thus, all that needs to be done is to allocate the
     // remaining stack slots.
     if (FLAG_code_comments) __ RecordComment("-- OSR entrypoint --");
@@ skipping 59 matching lines @@
       if (!((1 << i) & saves_fp)) continue;
       __ movdqu(XMMRegister::from_code(i),
                 Operand(rsp, kQuadWordSize * slot_idx));
       slot_idx++;
     }
     // Adjust the stack pointer.
     __ addp(rsp, Immediate(stack_size));
   }
 
   if (descriptor->IsCFunctionCall()) {
-    __ movq(rsp, rbp);  // Move stack pointer back to frame pointer.
-    __ popq(rbp);       // Pop caller's frame pointer.
-  } else if (frame()->needs_frame()) {
-    // Canonicalize JSFunction return sites for now.
-    if (return_label_.is_bound()) {
-      __ jmp(&return_label_);
-      return;
-    } else {
-      __ bind(&return_label_);
-      __ movq(rsp, rbp);  // Move stack pointer back to frame pointer.
-      __ popq(rbp);       // Pop caller's frame pointer.
-    }
+    AssembleDeconstructFrameIfNeeded();
+  } else if (frame_access_state()->has_frame()) {
+    if (AssembleDeconstructFrameUsingReturnLabel()) return;
   }
   size_t pop_size = descriptor->StackParameterCount() * kPointerSize;
   // Might need rcx for scratch if pop_size is too big.
   DCHECK_EQ(0u, descriptor->CalleeSavedRegisters() & rcx.bit());
   __ Ret(static_cast<int>(pop_size), rcx);
 }
 
 
 void CodeGenerator::AssembleMove(InstructionOperand* source,
                                  InstructionOperand* destination) {
@@ skipping 198 matching lines @@
     int padding_size = last_lazy_deopt_pc_ + space_needed - current_pc;
     __ Nop(padding_size);
   }
 }
 
 #undef __
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8