Fix stack walking when top frame has null method pointer.

Changed the do-while loop to just a while loop in the stack walk. This
fixes the case where the top frame has a null method pointer, which can
happen during instrumentation.

Change-Id: If7d67cd315d31bac4c1bbe31d6e385612b182935

1 files changed, 2 insertions, 2 deletions

diff --git a/src/stack.cc b/src/stack.cc
index e962dec8b6..228f96d31d 100644
--- a/src/stack.cc
+++ b/src/stack.cc
@@ -221,7 +221,7 @@ void StackVisitor::WalkStack(bool include_transitions) {
       // Can't be both a shadow and a quick fragment.
       DCHECK(current_fragment->GetTopShadowFrame() == NULL);
       AbstractMethod* method = *cur_quick_frame_;
-      do {
+      while (method != NULL) {
         SanityCheckFrame();
         bool should_continue = VisitFrame();
         if (UNLIKELY(!should_continue)) {
@@ -253,7 +253,7 @@ void StackVisitor::WalkStack(bool include_transitions) {
         cur_quick_frame_ = reinterpret_cast<AbstractMethod**>(next_frame);
         cur_depth_++;
         method = *cur_quick_frame_;
-      } while (method != NULL);
+      }
     } else if (cur_shadow_frame_ != NULL) {
       do {
         SanityCheckFrame();