Port a couple more stubs to x64.

runtime/vm/cpu_x64.cc

-// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
+// Copyright (c) 2012, 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_X64)
 
 #include "vm/cpu.h"
 
+#include "vm/constants_x64.h"
+#include "vm/heap.h"
+#include "vm/isolate.h"
+#include "vm/object.h"
+
 namespace dart {
 
 void CPU::FlushICache(uword start, uword size) {
   // Nothing to be done here.
 }
 
 
-void CPU::JumpToExceptionHandler(uword pc,
-                                 uword sp,
-                                 uword fp,
+void CPU::JumpToExceptionHandler(uword program_counter,
+                                 uword stack_pointer,
+                                 uword frame_pointer,
                                  const Instance& exception_object,
                                  const Instance& stacktrace_object) {
+  NoGCScope no_gc;

[Ivan Posva, 2012/01/13 06:27:40]

This is also in the ia32 code, but I was wondering how the destructor for this
stack object is ever called.

Tracing what happens, I realized that since NoGCScope is a StackResource and it
will be unwound by the general unwinding code below. That is rather twisted and
probably needs a comment somewhere. How about adding this here, below and in the
cpu_ia32.cc file?

 // The no_gc StackResource is unwound through the tear down of stack resources
below.
NoGCScope no_gc; 

[regis, 2012/01/13 18:57:31]

Done here, below, and in cpu_ia32.cc.

+  RawInstance* exception = exception_object.raw();
+  RawInstance* stacktrace = stacktrace_object.raw();
+
+  // Prepare for unwinding frames by destroying all the stack resources
+  // in the previous frames.
+  Isolate* isolate = Isolate::Current();
+  while (isolate->top_resource() != NULL &&
+         (reinterpret_cast<uword>(isolate->top_resource()) < stack_pointer)) {
+    isolate->top_resource()->~StackResource();
+  }
+
+  // Set up the appropriate register state and jump to the handler.
+  ASSERT(kExceptionObjectReg == RAX);
+  ASSERT(kStackTraceObjectReg == RDX);
+#if defined(TARGET_OS_WINDOWS)
   UNIMPLEMENTED();
+#else
+  asm volatile("mov %[exception], %%rax;"
+               "mov %[stacktrace], %%rdx;"
+               "mov %[pc], %%rbx;"
+               "mov %[fp], %%rcx;"
+               "mov %[sp], %%rdi;"
+               "mov %%rcx, %%rbp;"
+               "mov %%rdi, %%rsp;"
+               "jmp *%%rbx;"
+               :
+               : [exception] "m" (exception),
+                 [stacktrace] "m" (stacktrace),
+                 [pc] "m" (program_counter),
+                 [sp] "m" (stack_pointer),
+                 [fp] "m" (frame_pointer));
+#endif
+  UNREACHABLE();
 }
 
 
 void CPU::JumpToUnhandledExceptionHandler(
-    uword pc,
-    uword sp,
-    uword fp,
-    const UnhandledException& unhandled_exception) {
+    uword program_counter,
+    uword stack_pointer,
+    uword frame_pointer,
+    const UnhandledException& unhandled_exception_object) {
+  NoGCScope no_gc;
+  ASSERT(!unhandled_exception_object.IsNull());
+  RawUnhandledException* unhandled_exception = unhandled_exception_object.raw();
+
+  // Prepare for unwinding frames by destroying all the stack resources
+  // in the previous frames.
+  Isolate* isolate = Isolate::Current();
+  while (isolate->top_resource() != NULL &&
+         (reinterpret_cast<uword>(isolate->top_resource()) < stack_pointer)) {
+    isolate->top_resource()->~StackResource();
+  }
+
+  // Set up the unhandled exception object as the return value in EAX

[Ivan Posva, 2012/01/13 06:27:40]

EAX -> RAX

[regis, 2012/01/13 18:57:31]

Done.

+  // and continue from the invocation stub.
+#if defined(TARGET_OS_WINDOWS)
   UNIMPLEMENTED();
+#else
+  asm volatile("mov %[unhandled_exception], %%rax;"
+               "mov %[pc], %%rbx;"
+               "mov %[fp], %%rcx;"
+               "mov %[sp], %%rdi;"
+               "mov %%rcx, %%rbp;"
+               "mov %%rdi, %%rsp;"
+               "jmp *%%rbx;"
+               :
+               : [unhandled_exception] "m" (unhandled_exception),
+                 [pc] "m" (program_counter),
+                 [sp] "m" (stack_pointer),
+                 [fp] "m" (frame_pointer));
+#endif
+  UNREACHABLE();
 }
 
 
 const char* CPU::Id() {
   return "x64";
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64