JumpToFrame refactor

runtime/vm/stub_code_ia32.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_IA32)
 
 #include "vm/assembler.h"
 #include "vm/compiler.h"
 #include "vm/dart_entry.h"
@@ skipping 1774 matching lines @@
 
 // Return the current stack pointer address, used to do stack alignment checks.
 // TOS + 0: return address
 // Result in EAX.
 void StubCode::GenerateGetStackPointerStub(Assembler* assembler) {
   __ leal(EAX, Address(ESP, kWordSize));
   __ ret();
 }
 
 
-// Jump to the exception or error handler.
+// Jump to a frame on the call stack.
 // TOS + 0: return address
 // TOS + 1: program_counter
 // TOS + 2: stack_pointer
 // TOS + 3: frame_pointer
-// TOS + 4: exception object
-// TOS + 5: stacktrace object
-// TOS + 6: thread
+// TOS + 4: thread
 // No Result.
-void StubCode::GenerateJumpToExceptionHandlerStub(Assembler* assembler) {
-  ASSERT(kExceptionObjectReg == EAX);
-  ASSERT(kStackTraceObjectReg == EDX);
-  __ movl(THR, Address(ESP, 6 * kWordSize));  // Load target thread.
-  __ movl(kStackTraceObjectReg, Address(ESP, 5 * kWordSize));
-  __ movl(kExceptionObjectReg, Address(ESP, 4 * kWordSize));
+void StubCode::GenerateJumpToFrameStub(Assembler* assembler) {
+  __ movl(THR, Address(ESP, 4 * kWordSize));  // Load target thread.
   __ movl(EBP, Address(ESP, 3 * kWordSize));  // Load target frame_pointer.
   __ movl(EBX, Address(ESP, 1 * kWordSize));  // Load target PC into EBX.
   __ movl(ESP, Address(ESP, 2 * kWordSize));  // Load target stack_pointer.
   // Set tag.
   __ movl(Assembler::VMTagAddress(), Immediate(VMTag::kDartTagId));
   // Clear top exit frame.
   __ movl(Address(THR, Thread::top_exit_frame_info_offset()), Immediate(0));
   __ jmp(EBX);  // Jump to the exception handler code.
 }
 
 
+// Run an exception handler.  Execution comes from JumpToFrame stub.
+//
+// The arguments are stored in the Thread object.
+// No result.
+void StubCode::GenerateRunExceptionHandlerStub(Assembler* assembler) {
+  ASSERT(kExceptionObjectReg == EAX);
+  ASSERT(kStackTraceObjectReg == EDX);
+  __ movl(EBX, Address(THR, Thread::resume_pc_offset()));
+
+  // Load the exception from the current thread.
+  Address exception_addr(THR, Thread::active_exception_offset());
+  __ movl(kExceptionObjectReg, exception_addr);
+  __ movl(exception_addr, Immediate(0));
+
+  // Load the stacktrace from the current thread.
+  Address stacktrace_addr(THR, Thread::active_stacktrace_offset());
+  __ movl(kStackTraceObjectReg, stacktrace_addr);
+  __ movl(stacktrace_addr, Immediate(0));
+
+  __ jmp(EBX);  // Jump to continuation point.
+}
+
+
 // Calls to the runtime to optimize the given function.
 // EBX: function to be reoptimized.
 // EDX: argument descriptor (preserved).
 void StubCode::GenerateOptimizeFunctionStub(Assembler* assembler) {
   __ EnterStubFrame();
   __ pushl(EDX);
   __ pushl(Immediate(0));  // Setup space on stack for return value.
   __ pushl(EBX);
   __ CallRuntime(kOptimizeInvokedFunctionRuntimeEntry, 1);
   __ popl(EAX);  // Discard argument.
@@ skipping 222 matching lines @@
 }
 
 
 void StubCode::GenerateFrameAwaitingMaterializationStub(Assembler* assembler) {
   __ int3();
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_IA32