One more iteration of PcDescriptor iterator improvement: do not copy record but access individual …

runtime/vm/stack_frame.cc

Index: runtime/vm/stack_frame.cc
===================================================================
--- runtime/vm/stack_frame.cc	(revision 38356)
+++ runtime/vm/stack_frame.cc	(working copy)
@@ -226,11 +226,11 @@
   descriptors = code.pc_descriptors();
   PcDescriptors::Iterator iter(descriptors, RawPcDescriptors::kAnyKind);
   while (iter.HasNext()) {
-    RawPcDescriptors::PcDescriptorRec rec;
-    iter.NextRec(&rec);
-    if ((rec.pc() == pc()) && (rec.try_index() != -1)) {
+    const uword current_pc = iter.NextPc();
+    const intptr_t current_try_index = iter.current_try_index();
+    if ((current_pc == pc()) && (current_try_index != -1)) {
       RawExceptionHandlers::HandlerInfo handler_info;
-      handlers.GetHandlerInfo(rec.try_index(), &handler_info);
+      handlers.GetHandlerInfo(current_try_index, &handler_info);
       *handler_pc = handler_info.handler_pc;
       *needs_stacktrace = handler_info.needs_stacktrace;
       *has_catch_all = handler_info.has_catch_all;
@@ -251,10 +251,9 @@
   ASSERT(!descriptors.IsNull());
   PcDescriptors::Iterator iter(descriptors, RawPcDescriptors::kAnyKind);
   while (iter.HasNext()) {
-    RawPcDescriptors::PcDescriptorRec rec;
-    iter.NextRec(&rec);
-    if (rec.pc() == pc()) {
-      return rec.token_pos();
+    const uword current_pc = iter.NextPc();
+    if (current_pc == pc()) {
+      return iter.current_token_pos();
     }
   }
   return -1;