Consolidate debug stubs

runtime/vm/code_generator.cc

Index: runtime/vm/code_generator.cc
===================================================================
--- runtime/vm/code_generator.cc	(revision 23045)
+++ runtime/vm/code_generator.cc	(working copy)
@@ -809,25 +809,21 @@
 
 // Gets called from debug stub when code reaches a breakpoint before
 // calling a closure.

[siva, 2013/05/23 01:11:26]

The comment is a bit dated....

[hausner, 2013/05/23 18:32:12]

Done.

-DEFINE_RUNTIME_ENTRY(BreakpointClosureHandler, 0) {
+DEFINE_RUNTIME_ENTRY(BreakpointRuntimeHandler, 0) {
   ASSERT(arguments.ArgCount() ==
-         kBreakpointClosureHandlerRuntimeEntry.argument_count());
+         kBreakpointRuntimeHandlerRuntimeEntry.argument_count());
   ASSERT(isolate->debugger() != NULL);
+  DartFrameIterator iterator;
+  StackFrame* caller_frame = iterator.NextFrame();
+  ASSERT(caller_frame != NULL);
+  uword orig_stub =
+      isolate->debugger()->GetPatchedStubAddress(caller_frame->pc());
   isolate->debugger()->SignalBpReached();
+  ASSERT((orig_stub & kSmiTagMask) == kSmiTag);

[siva, 2013/05/23 01:11:26]

Is this assert guaranteed to hold always?

[hausner, 2013/05/23 18:32:12]

The assert is here to make sure we catch a case where it's not the case :). The
beginning of a stub or function should always be at an even address.

+  arguments.SetReturn(Smi::Handle(reinterpret_cast<RawSmi*>(orig_stub)));
 }
 
 
-// Gets called from debug stub when code reaches a breakpoint
-// at the stub call to update the ic cache on equality comparison
-// with null.
-DEFINE_RUNTIME_ENTRY(BreakpointEqualNullHandler, 0) {
-  ASSERT(arguments.ArgCount() ==
-         kBreakpointEqualNullHandlerRuntimeEntry.argument_count());
-  ASSERT(isolate->debugger() != NULL);
-  isolate->debugger()->SignalBpReached();
-}
-
-
 // Gets called from debug stub when code reaches a breakpoint.
 DEFINE_RUNTIME_ENTRY(BreakpointStaticHandler, 0) {
   ASSERT(arguments.ArgCount() ==