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

src/arm/builtins-arm.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_ARM
 
 #include "src/codegen.h"
 #include "src/debug/debug.h"
 #include "src/deoptimizer.h"
 #include "src/full-codegen/full-codegen.h"
@@ skipping 941 matching lines @@
 
 void Builtins::Generate_JSEntryTrampoline(MacroAssembler* masm) {
   Generate_JSEntryTrampolineHelper(masm, false);
 }
 
 
 void Builtins::Generate_JSConstructEntryTrampoline(MacroAssembler* masm) {
   Generate_JSEntryTrampolineHelper(masm, true);
 }
 
-
 // Generate code for entering a JS function with the interpreter.
 // On entry to the function the receiver and arguments have been pushed on the
 // stack left to right.  The actual argument count matches the formal parameter
 // count expected by the function.
 //
 // The live registers are:
 //   o r1: the JS function object being called.
 //   o r3: the new target
 //   o cp: our context
 //   o pp: the caller's constant pool pointer (if enabled)
@@ skipping 80 matching lines @@
   __ mov(kInterpreterDispatchTableRegister,
          Operand(ExternalReference::interpreter_dispatch_table_address(
              masm->isolate())));
 
   // Dispatch to the first bytecode handler for the function.
   __ ldrb(r1, MemOperand(kInterpreterBytecodeArrayRegister,
                          kInterpreterBytecodeOffsetRegister));
   __ ldr(ip, MemOperand(kInterpreterDispatchTableRegister, r1, LSL,
                         kPointerSizeLog2));
   __ Call(ip);
+  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 r0.
+
+  // Get the arguments + reciever count.
+  __ ldr(r2, MemOperand(fp, InterpreterFrameConstants::kBytecodeArrayFromFp));
+  __ ldr(r2, FieldMemOperand(r2, BytecodeArray::kParameterSizeOffset));
+
+  // Leave the frame (also dropping the register file).
+  __ LeaveFrame(StackFrame::JAVA_SCRIPT);
+
+  __ add(sp, sp, r2, LeaveCC);
+  __ Jump(lr);
 
   // 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);
   __ LeaveFrame(StackFrame::JAVA_SCRIPT);
   __ ldr(r4, FieldMemOperand(r1, JSFunction::kSharedFunctionInfoOffset));
   __ ldr(r4, FieldMemOperand(r4, SharedFunctionInfo::kCodeOffset));
   __ add(r4, r4, Operand(Code::kHeaderSize - kHeapObjectTag));
   __ str(r4, FieldMemOperand(r1, JSFunction::kCodeEntryOffset));
   __ RecordWriteCodeEntryField(r1, r4, r5);
   __ Jump(r4);
 }
 
-
-void Builtins::Generate_InterpreterExitTrampoline(MacroAssembler* masm) {
-  // The return value is in accumulator, which is already in r0.
-
-  // Leave the frame (also dropping the register file).
-  __ LeaveFrame(StackFrame::JAVA_SCRIPT);
-
-  // Drop receiver + arguments and return.
-  __ ldr(ip, FieldMemOperand(kInterpreterBytecodeArrayRegister,
-                             BytecodeArray::kParameterSizeOffset));
-  __ add(sp, sp, ip, LeaveCC);
-  __ Jump(lr);
-}
-
-
 static void Generate_InterpreterPushArgs(MacroAssembler* masm, Register index,
                                          Register limit, Register scratch) {
   Label loop_header, loop_check;
   __ b(al, &loop_check);
   __ bind(&loop_header);
   __ ldr(scratch, MemOperand(index, -kPointerSize, PostIndex));
   __ push(scratch);
   __ bind(&loop_check);
   __ cmp(index, limit);
   __ b(gt, &loop_header);
 }
 
-
 // static
 void Builtins::Generate_InterpreterPushArgsAndCallImpl(
     MacroAssembler* masm, TailCallMode tail_call_mode) {
   // ----------- S t a t e -------------
   //  -- r0 : the number of arguments (not including the receiver)
   //  -- r2 : 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.
   //  -- r1 : the target to call (can be any Object).
   // -----------------------------------
 
   // Find the address of the last argument.
   __ add(r3, r0, Operand(1));  // Add one for receiver.
   __ mov(r3, Operand(r3, LSL, kPointerSizeLog2));
   __ sub(r3, r2, r3);
 
   // Push the arguments.
   Generate_InterpreterPushArgs(masm, r2, r3, r4);
 
   // Call the target.
   __ 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 -------------
   // -- r0 : argument count (not including receiver)
   // -- r3 : new target
   // -- r1 : constructor to call
   // -- r2 : address of the first argument
   // -----------------------------------
 
   // Find the address of the last argument.
   __ mov(r4, Operand(r0, LSL, kPointerSizeLog2));
   __ sub(r4, r2, r4);
 
   // Push a slot for the receiver to be constructed.
   __ mov(ip, Operand::Zero());
   __ push(ip);
 
   // Push the arguments.
   Generate_InterpreterPushArgs(masm, r2, r4, r5);
 
   // Call the constructor with r0, r1, and r3 unmodified.
   __ 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(r2, masm->isolate()->builtins()->InterpreterEntryTrampoline());
+  __ add(lr, r2, Operand(interpreter_entry_return_pc_offset->value() +
+                         Code::kHeaderSize - kHeapObjectTag));
 
-static void Generate_EnterBytecodeDispatch(MacroAssembler* masm) {
   // Initialize the dispatch table register.
   __ mov(kInterpreterDispatchTableRegister,
          Operand(ExternalReference::interpreter_dispatch_table_address(
              masm->isolate())));
 
   // Get the bytecode array pointer from the frame.
   __ ldr(kInterpreterBytecodeArrayRegister,
          MemOperand(fp, InterpreterFrameConstants::kBytecodeArrayFromFp));
 
   if (FLAG_debug_code) {
@@ skipping 11 matching lines @@
   __ SmiUntag(kInterpreterBytecodeOffsetRegister);
 
   // Dispatch to the target bytecode.
   __ ldrb(r1, MemOperand(kInterpreterBytecodeArrayRegister,
                          kInterpreterBytecodeOffsetRegister));
   __ ldr(ip, MemOperand(kInterpreterDispatchTableRegister, r1, LSL,
                         kPointerSizeLog2));
   __ mov(pc, ip);
 }
 
-
-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.
-    __ mov(r1, Operand(Smi::FromInt(static_cast<int>(type))));
-    __ push(r1);
-    __ 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.
-  __ Drop(1);
-  __ Pop(kInterpreterAccumulatorRegister);
-
-  // 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.
-  __ Move(lr, masm->isolate()->builtins()->InterpreterEntryTrampoline());
-
-  Generate_EnterBytecodeDispatch(masm);
-}
-
-
 void Builtins::Generate_CompileLazy(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- r0 : argument count (preserved for callee)
   //  -- r3 : new target (preserved for callee)
   //  -- r1 : target function (preserved for callee)
   // -----------------------------------
   // First lookup code, maybe we don't need to compile!
   Label gotta_call_runtime, gotta_call_runtime_no_stack;
   Label maybe_call_runtime;
   Label try_shared;
@@ skipping 269 matching lines @@
     __ mov(r0, Operand(Smi::FromInt(static_cast<int>(type))));
     __ push(r0);
     __ CallRuntime(Runtime::kNotifyDeoptimized);
   }
 
   // Get the full codegen state from the stack and untag it -> r6.
   __ ldr(r6, MemOperand(sp, 0 * kPointerSize));
   __ SmiUntag(r6);
   // Switch on the state.
   Label with_tos_register, unknown_state;
-  __ cmp(r6, Operand(FullCodeGenerator::NO_REGISTERS));
+  __ cmp(r6,
+         Operand(static_cast<int>(Deoptimizer::BailoutState::NO_REGISTERS)));
   __ b(ne, &with_tos_register);
   __ add(sp, sp, Operand(1 * kPointerSize));  // Remove state.
   __ Ret();
 
   __ bind(&with_tos_register);
+  DCHECK_EQ(kInterpreterAccumulatorRegister.code(), r0.code());
   __ ldr(r0, MemOperand(sp, 1 * kPointerSize));
-  __ cmp(r6, Operand(FullCodeGenerator::TOS_REG));
+  __ cmp(r6,
+         Operand(static_cast<int>(Deoptimizer::BailoutState::TOS_REGISTER)));
   __ b(ne, &unknown_state);
   __ add(sp, sp, Operand(2 * kPointerSize));  // Remove state.
   __ Ret();
 
   __ bind(&unknown_state);
   __ stop("no cases left");
 }
 
 
 void Builtins::Generate_NotifyDeoptimized(MacroAssembler* masm) {
@@ skipping 1263 matching lines @@
   }
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_ARM