JumpToFrame refactor

runtime/vm/stub_code_arm.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"
 #if defined(TARGET_ARCH_ARM)
 
 #include "vm/assembler.h"
 #include "vm/code_generator.h"
 #include "vm/cpu.h"
@@ skipping 1832 matching lines @@
 }
 
 
 // Return the current stack pointer address, used to do stack alignment checks.
 void StubCode::GenerateGetStackPointerStub(Assembler* assembler) {
   __ mov(R0, Operand(SP));
   __ Ret();
 }
 
 
-// Jump to the exception or error handler.
+// Jump to a frame on the call stack.
 // LR: return address.
 // R0: program_counter.
 // R1: stack_pointer.
 // R2: frame_pointer.
-// R3: error object.
-// SP + 0: address of stacktrace object.
-// SP + 4: thread.
+// R3: thread.
 // Does not return.
-void StubCode::GenerateJumpToExceptionHandlerStub(Assembler* assembler) {
+void StubCode::GenerateJumpToFrameStub(Assembler* assembler) {
   ASSERT(kExceptionObjectReg == R0);
   ASSERT(kStackTraceObjectReg == R1);
   __ mov(IP, Operand(R1));      // Copy Stack pointer into IP.
   __ mov(LR, Operand(R0));      // Program counter.
-  __ mov(R0, Operand(R3));      // Exception object.
-  __ ldr(R1, Address(SP, 0));   // StackTrace object.
-  __ ldr(THR, Address(SP, 4));  // Thread.
+  __ mov(THR, Operand(R3));     // Thread.
   __ mov(FP, Operand(R2));      // Frame_pointer.
   __ mov(SP, Operand(IP));      // Set Stack pointer.
   // Set the tag.
   __ LoadImmediate(R2, VMTag::kDartTagId);
   __ StoreToOffset(kWord, R2, THR, Thread::vm_tag_offset());
   // Clear top exit frame.
   __ LoadImmediate(R2, 0);
   __ StoreToOffset(kWord, R2, THR, Thread::top_exit_frame_info_offset());
   // Restore the pool pointer.
   __ RestoreCodePointer();
   __ LoadPoolPointer();
+  __ bx(LR);  // Jump to continuation point.
+}
+
+
+// Run an exception handler.  Execution comes from JumpToFrame
+// stub or from the simulator.
+//
+// The arguments are stored in the Thread object.
+// Does not return.
+void StubCode::GenerateRunExceptionHandlerStub(Assembler* assembler) {
+  __ LoadFromOffset(kWord, LR, THR, Thread::resume_pc_offset());
+  __ LoadImmediate(R2, 0);
+
+  // Exception object.
+  __ LoadFromOffset(kWord, R0, THR, Thread::active_exception_offset());
+  __ StoreToOffset(kWord, R2, THR, Thread::active_exception_offset());
+
+  // Stacktrace object.
+  __ LoadFromOffset(kWord, R1, THR, Thread::active_stacktrace_offset());
+  __ StoreToOffset(kWord, R2, THR, Thread::active_stacktrace_offset());
+
   __ bx(LR);  // Jump to the exception handler code.
 }
 
 
 // Calls to the runtime to optimize the given function.
 // R8: function to be reoptimized.
 // R4: argument descriptor (preserved).
 void StubCode::GenerateOptimizeFunctionStub(Assembler* assembler) {
   __ EnterStubFrame();
   __ Push(R4);
@@ skipping 350 matching lines @@
 }
 
 
 void StubCode::GenerateFrameAwaitingMaterializationStub(Assembler* assembler) {
   __ bkpt(0);
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM