[Interpreter] Remove InterpreterExitTrampoline and replace with returning to the entry trampoline.

src/x64/builtins-x64.cc

 // Copyright 2012 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.
 
 #if V8_TARGET_ARCH_X64
 
 #include "src/code-factory.h"
 #include "src/codegen.h"
 #include "src/deoptimizer.h"
 #include "src/full-codegen/full-codegen.h"
@@ skipping 681 matching lines @@
   __ Move(
       kInterpreterDispatchTableRegister,
       ExternalReference::interpreter_dispatch_table_address(masm->isolate()));
 
   // Dispatch to the first bytecode handler for the function.
   __ movzxbp(rbx, Operand(kInterpreterBytecodeArrayRegister,
                           kInterpreterBytecodeOffsetRegister, times_1, 0));
   __ movp(rbx, Operand(kInterpreterDispatchTableRegister, rbx,
                        times_pointer_size, 0));
   __ call(rbx);
+  masm->isolate()->heap()->SetInterpreterEntryReturnPCOffset(masm->pc_offset());
 
-  // Even though the first bytecode handler was called, we will never return.
-  __ Abort(kUnexpectedReturnFromBytecodeHandler);
+  // The return value is in rax.
+
+  // Get the arguments + reciever count.
+  __ movp(rbx, Operand(rbp, InterpreterFrameConstants::kBytecodeArrayFromFp));
+  __ movl(rbx, FieldOperand(rbx, BytecodeArray::kParameterSizeOffset));
+
+  // Leave the frame (also dropping the register file).
+  __ leave();
+
+  // Drop receiver + arguments and return.
+  __ PopReturnAddressTo(rcx);
+  __ addp(rsp, rbx);
+  __ PushReturnAddressFrom(rcx);
+  __ ret(0);
 
   // Load debug copy of the bytecode array.
   __ bind(&load_debug_bytecode_array);
   Register debug_info = kInterpreterBytecodeArrayRegister;
   __ movp(debug_info, FieldOperand(rax, SharedFunctionInfo::kDebugInfoOffset));
   __ movp(kInterpreterBytecodeArrayRegister,
           FieldOperand(debug_info, DebugInfo::kAbstractCodeIndex));
   __ jmp(&bytecode_array_loaded);
 
   // If the bytecode array is no longer present, then the underlying function
   // has been switched to a different kind of code and we heal the closure by
   // switching the code entry field over to the new code object as well.
   __ bind(&bytecode_array_not_present);
   __ leave();  // Leave the frame so we can tail call.
   __ movp(rcx, FieldOperand(rdi, JSFunction::kSharedFunctionInfoOffset));
   __ movp(rcx, FieldOperand(rcx, SharedFunctionInfo::kCodeOffset));
   __ leap(rcx, FieldOperand(rcx, Code::kHeaderSize));
   __ movp(FieldOperand(rdi, JSFunction::kCodeEntryOffset), rcx);
   __ RecordWriteCodeEntryField(rdi, rcx, r15);
   __ jmp(rcx);
 }
 
-
-void Builtins::Generate_InterpreterExitTrampoline(MacroAssembler* masm) {
-  // The return value is in accumulator, which is already in rax.
-
-  // Leave the frame (also dropping the register file).
-  __ leave();
-
-  // Drop receiver + arguments and return.
-  __ movl(rbx, FieldOperand(kInterpreterBytecodeArrayRegister,
-                            BytecodeArray::kParameterSizeOffset));
-  __ PopReturnAddressTo(rcx);
-  __ addp(rsp, rbx);
-  __ PushReturnAddressFrom(rcx);
-  __ ret(0);
-}
-
-
 static void Generate_InterpreterPushArgs(MacroAssembler* masm,
                                          bool push_receiver) {
   // ----------- S t a t e -------------
   //  -- rax : the number of arguments (not including the receiver)
   //  -- rbx : the address of the first argument to be pushed. Subsequent
   //           arguments should be consecutive above this, in the same order as
   //           they are to be pushed onto the stack.
   // -----------------------------------
 
   // Find the address of the last argument.
@@ skipping 10 matching lines @@
   Label loop_header, loop_check;
   __ j(always, &loop_check);
   __ bind(&loop_header);
   __ Push(Operand(rbx, 0));
   __ subp(rbx, Immediate(kPointerSize));
   __ bind(&loop_check);
   __ cmpp(rbx, rcx);
   __ j(greater, &loop_header, Label::kNear);
 }
 
-
 // static
 void Builtins::Generate_InterpreterPushArgsAndCallImpl(
     MacroAssembler* masm, TailCallMode tail_call_mode) {
   // ----------- S t a t e -------------
   //  -- rax : the number of arguments (not including the receiver)
   //  -- rbx : the address of the first argument to be pushed. Subsequent
   //           arguments should be consecutive above this, in the same order as
   //           they are to be pushed onto the stack.
   //  -- rdi : the target to call (can be any Object).
   // -----------------------------------
 
   // Pop return address to allow tail-call after pushing arguments.
   __ PopReturnAddressTo(kScratchRegister);
 
   Generate_InterpreterPushArgs(masm, true);
 
   // Call the target.
   __ PushReturnAddressFrom(kScratchRegister);  // Re-push return address.
   __ Jump(masm->isolate()->builtins()->Call(ConvertReceiverMode::kAny,
                                             tail_call_mode),
           RelocInfo::CODE_TARGET);
 }
 
-
 // static
 void Builtins::Generate_InterpreterPushArgsAndConstruct(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- rax : the number of arguments (not including the receiver)
   //  -- rdx : the new target (either the same as the constructor or
   //           the JSFunction on which new was invoked initially)
   //  -- rdi : the constructor to call (can be any Object)
   //  -- rbx : the address of the first argument to be pushed. Subsequent
   //           arguments should be consecutive above this, in the same order as
   //           they are to be pushed onto the stack.
   // -----------------------------------
 
   // Pop return address to allow tail-call after pushing arguments.
   __ PopReturnAddressTo(kScratchRegister);
 
   // Push slot for the receiver to be constructed.
   __ Push(Immediate(0));
 
   Generate_InterpreterPushArgs(masm, false);
 
   // Push return address in preparation for the tail-call.
   __ PushReturnAddressFrom(kScratchRegister);
 
   // Call the constructor (rax, rdx, rdi passed on).
   __ Jump(masm->isolate()->builtins()->Construct(), RelocInfo::CODE_TARGET);
 }
 
+void Builtins::Generate_InterpreterEnterBytecodeDispatch(MacroAssembler* masm) {
+  // Set the return address to the correct point in the interpreter entry
+  // trampoline.
+  Smi* interpreter_entry_return_pc_offset(
+      masm->isolate()->heap()->interpreter_entry_return_pc_offset());
+  DCHECK_NE(interpreter_entry_return_pc_offset, Smi::FromInt(0));
+  __ Move(rbx, masm->isolate()->builtins()->InterpreterEntryTrampoline());
+  __ addp(rbx, Immediate(interpreter_entry_return_pc_offset->value() +
+                         Code::kHeaderSize - kHeapObjectTag));
+  __ Push(rbx);
 
-static void Generate_EnterBytecodeDispatch(MacroAssembler* masm) {
   // Initialize dispatch table register.
   __ Move(
       kInterpreterDispatchTableRegister,
       ExternalReference::interpreter_dispatch_table_address(masm->isolate()));
 
   // Get the bytecode array pointer from the frame.
   __ movp(kInterpreterBytecodeArrayRegister,
           Operand(rbp, InterpreterFrameConstants::kBytecodeArrayFromFp));
 
   if (FLAG_debug_code) {
@@ skipping 11 matching lines @@
                     kInterpreterBytecodeOffsetRegister);
 
   // Dispatch to the target bytecode.
   __ movzxbp(rbx, Operand(kInterpreterBytecodeArrayRegister,
                           kInterpreterBytecodeOffsetRegister, times_1, 0));
   __ movp(rbx, Operand(kInterpreterDispatchTableRegister, rbx,
                        times_pointer_size, 0));
   __ jmp(rbx);
 }
 
-
-static void Generate_InterpreterNotifyDeoptimizedHelper(
-    MacroAssembler* masm, Deoptimizer::BailoutType type) {
-  // Enter an internal frame.
-  {
-    FrameScope scope(masm, StackFrame::INTERNAL);
-
-    // Pass the deoptimization type to the runtime system.
-    __ Push(Smi::FromInt(static_cast<int>(type)));
-    __ CallRuntime(Runtime::kNotifyDeoptimized);
-    // Tear down internal frame.
-  }
-
-  // Drop state (we don't use these for interpreter deopts) and and pop the
-  // accumulator value into the accumulator register and push PC at top
-  // of stack (to simulate initial call to bytecode handler in interpreter entry
-  // trampoline).
-  __ Pop(rbx);
-  __ Drop(1);
-  __ Pop(kInterpreterAccumulatorRegister);
-  __ Push(rbx);
-
-  // Enter the bytecode dispatch.
-  Generate_EnterBytecodeDispatch(masm);
-}
-
-
-void Builtins::Generate_InterpreterNotifyDeoptimized(MacroAssembler* masm) {
-  Generate_InterpreterNotifyDeoptimizedHelper(masm, Deoptimizer::EAGER);
-}
-
-
-void Builtins::Generate_InterpreterNotifySoftDeoptimized(MacroAssembler* masm) {
-  Generate_InterpreterNotifyDeoptimizedHelper(masm, Deoptimizer::SOFT);
-}
-
-
-void Builtins::Generate_InterpreterNotifyLazyDeoptimized(MacroAssembler* masm) {
-  Generate_InterpreterNotifyDeoptimizedHelper(masm, Deoptimizer::LAZY);
-}
-
-void Builtins::Generate_InterpreterEnterBytecodeDispatch(MacroAssembler* masm) {
-  // Set the address of the interpreter entry trampoline as a return address.
-  // This simulates the initial call to bytecode handlers in interpreter entry
-  // trampoline. The return will never actually be taken, but our stack walker
-  // uses this address to determine whether a frame is interpreted.
-  __ Push(masm->isolate()->builtins()->InterpreterEntryTrampoline());
-
-  Generate_EnterBytecodeDispatch(masm);
-}
-
-
 void Builtins::Generate_CompileLazy(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- rax : argument count (preserved for callee)
   //  -- rdx : new target (preserved for callee)
   //  -- rdi : target function (preserved for callee)
   // -----------------------------------
   // First lookup code, maybe we don't need to compile!
   Label gotta_call_runtime;
   Label maybe_call_runtime;
   Label try_shared;
@@ skipping 253 matching lines @@
 
     __ CallRuntime(Runtime::kNotifyDeoptimized);
     // Tear down internal frame.
   }
 
   // Get the full codegen state from the stack and untag it.
   __ SmiToInteger32(kScratchRegister, Operand(rsp, kPCOnStackSize));
 
   // Switch on the state.
   Label not_no_registers, not_tos_rax;
-  __ cmpp(kScratchRegister, Immediate(FullCodeGenerator::NO_REGISTERS));
+  __ cmpp(kScratchRegister,
+          Immediate(static_cast<int>(Deoptimizer::BailoutState::NO_REGISTERS)));
   __ j(not_equal, &not_no_registers, Label::kNear);
   __ ret(1 * kPointerSize);  // Remove state.
 
   __ bind(&not_no_registers);
+  DCHECK_EQ(kInterpreterAccumulatorRegister.code(), rax.code());
   __ movp(rax, Operand(rsp, kPCOnStackSize + kPointerSize));
-  __ cmpp(kScratchRegister, Immediate(FullCodeGenerator::TOS_REG));
+  __ cmpp(kScratchRegister,
+          Immediate(static_cast<int>(Deoptimizer::BailoutState::TOS_REGISTER)));
   __ j(not_equal, &not_tos_rax, Label::kNear);
   __ ret(2 * kPointerSize);  // Remove state, rax.
 
   __ bind(&not_tos_rax);
   __ Abort(kNoCasesLeft);
 }
 
 
 void Builtins::Generate_NotifyDeoptimized(MacroAssembler* masm) {
   Generate_NotifyDeoptimizedHelper(masm, Deoptimizer::EAGER);
@@ skipping 1754 matching lines @@
   __ ret(0);
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X64