Print stop message.

runtime/vm/assembler_ia32.cc

Index: runtime/vm/assembler_ia32.cc
===================================================================
--- runtime/vm/assembler_ia32.cc	(revision 3058)
+++ runtime/vm/assembler_ia32.cc	(working copy)
@@ -9,9 +9,13 @@
 #include "vm/heap.h"
 #include "vm/memory_region.h"
 #include "vm/runtime_entry.h"
+#include "vm/stub_code.h"
 
 namespace dart {
 
+DEFINE_FLAG(bool, print_stop_message, true, "Print stop message.");
+
+
 class DirectCallRelocation : public AssemblerFixup {
  public:
   void Process(const MemoryRegion& region, int position) {
@@ -1438,6 +1442,11 @@
 
 
 void Assembler::Stop(const char* message) {
+  if (FLAG_print_stop_message) {
+    pushl(Immediate(reinterpret_cast<int32_t>(message)));
+    call(&StubCode::PrintStopMessageLabel());
+    popl(EAX);

[Ivan Posva, 2012/01/09 17:26:42]

This destroys whatever was in EAX.

[regis, 2012/01/10 00:09:16]

Done.

+  }
   // Emit the message address as immediate operand in the test rax instruction,
   // followed by the int3 instruction.
   // Execution can be resumed with the 'cont' command in gdb.