Revert "Revert "JumpToFrame refactor"" + Fix

runtime/vm/stub_code_mips.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_MIPS)
 
 #include "vm/assembler.h"
 #include "vm/code_generator.h"
 #include "vm/compiler.h"
@@ skipping 1967 matching lines @@
   __ Ret();
   __ delay_slot()->mov(V0, SP);
 }
 
 
 // Jump to the exception or error handler.
 // RA: return address.
 // A0: program_counter.
 // A1: stack_pointer.
 // A2: frame_pointer.
-// A3: error object.
-// SP + 4*kWordSize: address of stacktrace object.
-// SP + 5*kWordSize: address of thread.
+// A3: thread.
 // Does not return.
-void StubCode::GenerateJumpToExceptionHandlerStub(Assembler* assembler) {
+void StubCode::GenerateJumpToFrameStub(Assembler* assembler) {
   ASSERT(kExceptionObjectReg == V0);
   ASSERT(kStackTraceObjectReg == V1);
-  __ mov(V0, A3);  // Exception object.
-  // MIPS ABI reserves stack space for all arguments. The StackTrace object is
-  // the last of five arguments, so it is first pushed on the stack.
-  __ lw(V1, Address(SP, 4 * kWordSize));   // StackTrace object.
-  __ mov(FP, A2);                          // Frame_pointer.
-  __ lw(THR, Address(SP, 5 * kWordSize));  // Thread.
+  __ mov(FP, A2);   // Frame_pointer.
+  __ mov(THR, A3);  // Thread.
   // Set tag.
   __ LoadImmediate(A2, VMTag::kDartTagId);
   __ sw(A2, Assembler::VMTagAddress());
   // Clear top exit frame.
   __ sw(ZR, Address(THR, Thread::top_exit_frame_info_offset()));
   // Restore pool pointer.
   __ RestoreCodePointer();
   __ LoadPoolPointer();
-  __ jr(A0);                     // Jump to the exception handler code.
+  __ jr(A0);                     // Jump to the program counter.
   __ delay_slot()->mov(SP, A1);  // Stack pointer.
 }
 
 
+// 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) {
+  __ lw(A0, Address(THR, Thread::resume_pc_offset()));
+  __ LoadImmediate(A2, 0);
+
+  // Load the exception from the current thread.
+  Address exception_addr(THR, Thread::active_exception_offset());
+  __ lw(V0, exception_addr);
+  __ sw(A2, exception_addr);
+
+  // Load the stacktrace from the current thread.
+  Address stacktrace_addr(THR, Thread::active_stacktrace_offset());
+  __ lw(V1, stacktrace_addr);
+
+  __ jr(A0);  // Jump to continuation point.
+  __ delay_slot()->sw(A2, stacktrace_addr);
+}
+
+
 // Calls to the runtime to optimize the given function.
 // T0: function to be reoptimized.
 // S4: argument descriptor (preserved).
 void StubCode::GenerateOptimizeFunctionStub(Assembler* assembler) {
   __ Comment("OptimizeFunctionStub");
   __ EnterStubFrame();
   __ addiu(SP, SP, Immediate(-3 * kWordSize));
   __ sw(S4, Address(SP, 2 * kWordSize));
   // Setup space on stack for return value.
   __ sw(ZR, Address(SP, 1 * kWordSize));
@@ skipping 357 matching lines @@
 }
 
 
 void StubCode::GenerateFrameAwaitingMaterializationStub(Assembler* assembler) {
   __ break_(0);
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_MIPS