Very first steps for a debugger

runtime/vm/code_generator.cc

 // Copyright (c) 2011, 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/code_generator.h"
 
 #include "vm/code_index_table.h"
 #include "vm/code_patcher.h"
 #include "vm/compiler.h"
 #include "vm/dart_api_impl.h"
@@ skipping 451 matching lines @@
 DEFINE_RUNTIME_ENTRY(ResolveCompileInstanceFunction, 1) {
   ASSERT(arguments.Count() ==
          kResolveCompileInstanceFunctionRuntimeEntry.argument_count());
   const Instance& receiver = Instance::CheckedHandle(arguments.At(0));
   const Code& code = Code::Handle(
       ResolveCompileInstanceCallTarget(isolate, receiver));
   arguments.SetReturn(Code::Handle(code.raw()));
 }
 
 
+// Gets called from debug stub when code reaches a breakpoint.
+DEFINE_RUNTIME_ENTRY(BreakpointHandler, 0) {
+  ASSERT(arguments.Count() == kBreakpointHandlerRuntimeEntry.argument_count());
+  DartFrameIterator iterator;
+  DartFrame* frame = iterator.NextFrame();
+  Function& func = Function::Handle();
+  ASSERT(frame != NULL);
+  OS::Print(">>> Breakpoint at 0x%08x\n", frame->pc());
+  while (frame != NULL) {
+    ASSERT(frame->IsValid());
+    ASSERT(frame->IsDartFrame());
+    func = frame->LookupDartFunction();
+    OS::Print("  func %s\n", String::Handle(func.name()).ToCString());
+    frame = iterator.NextFrame();
+  }
+}
+
+
 // Handles inline cache misses by updating the IC data array of the call
 // site.
 //   Arg0: Receiver object.
 //   Returns: target function with compiled code or 0.
 // Modifies the instance call to hold the updated IC data array.
 DEFINE_RUNTIME_ENTRY(InlineCacheMissHandler, 1) {
   ASSERT(arguments.Count() ==
       kInlineCacheMissHandlerRuntimeEntry.argument_count());
   const Instance& receiver = Instance::CheckedHandle(arguments.At(0));
   const Code& target_code =
@@ skipping 530 matching lines @@
       }
     }
   }
   // The cache is null terminated, therefore the loop above should never
   // terminate by itself.
   UNREACHABLE();
   return Code::null();
 }
 
 }  // namespace dart