Begin implementing flag --deoptimize-filter=FUNC for ia32.

runtime/vm/code_generator.cc

Index: runtime/vm/code_generator.cc
diff --git a/runtime/vm/code_generator.cc b/runtime/vm/code_generator.cc
index 7e96333cb67938709e21e6c212f31826b218adc0..923587480c83ad15e5092ec1b31250dfd0c8ac2d 100644
--- a/runtime/vm/code_generator.cc
+++ b/runtime/vm/code_generator.cc
@@ -60,6 +60,8 @@ DECLARE_FLAG(bool, report_usage_count);
 DEFINE_FLAG(bool, use_osr, true, "Use on-stack replacement.");
 DEFINE_FLAG(bool, trace_osr, false, "Trace attempts at on-stack replacement.");
 
+DECLARE_FLAG(charp, deoptimize_filter);
+
 
 DEFINE_RUNTIME_ENTRY(TraceFunctionEntry, 1) {
   const Function& function = Function::CheckedHandle(arguments.ArgAt(0));
@@ -1223,6 +1225,28 @@ DEFINE_RUNTIME_ENTRY(StackOverflow, 0) {
       frame->set_pc(optimized_entry);
     }
   }
+
+  if (FLAG_deoptimize_filter != NULL) {
+    DartFrameIterator iterator;
+    StackFrame* frame = iterator.NextFrame();
+    ASSERT(frame != NULL);
+    const Code& code = Code::Handle(frame->LookupDartCode());
+    ASSERT(!code.IsNull());
+    if (code.is_optimized()) {
+      const Function& function = Function::Handle(code.function());
+      ASSERT(!function.IsNull());
+      if (strstr(function.ToFullyQualifiedCString(),
+                 FLAG_deoptimize_filter) != NULL) {
+        if (FLAG_trace_deoptimization || FLAG_trace_deoptimization_verbose) {
+          OS::PrintErr("*** Forcing deoptimization (%s)\n",
+                       function.ToFullyQualifiedCString());
+          // TODO(turnidge): Consider changing to DeoptimizeAt for
+          // just the top frame.
+          DeoptimizeAll();
+        }
+      }
+    }
+  }
 }