Partial ia32 implementation of optimized try/catch (by Kevin Millikin)

src/frames.cc

Index: src/frames.cc
diff --git a/src/frames.cc b/src/frames.cc
index 18dc54164afc1a92bdefb7e5d837efd0b0850794..9f55733ad82ce289b37211e11afc0e2651c5a567 100644
--- a/src/frames.cc
+++ b/src/frames.cc
@@ -618,12 +618,6 @@ bool StandardFrame::IsExpressionInsideHandler(int n) const {
 
 
 void OptimizedFrame::Iterate(ObjectVisitor* v) const {
-#ifdef DEBUG
-  // Make sure that optimized frames do not contain any stack handlers.
-  StackHandlerIterator it(this, top_handler());
-  ASSERT(it.done());
-#endif
-
   // Make sure that we're not doing "safe" stack frame iteration. We cannot
   // possibly find pointers in optimized frames in that state.
   ASSERT(!SafeStackFrameIterator::is_active(isolate()));
@@ -669,8 +663,22 @@ void OptimizedFrame::Iterate(ObjectVisitor* v) const {
   uint8_t* safepoint_bits = safepoint_entry.bits();
   safepoint_bits += kNumSafepointRegisters >> kBitsPerByteLog2;
 
-  // Visit the rest of the parameters.
-  v->VisitPointers(parameters_base, parameters_limit);
+  // Visit the rest of the parameters and the exception handlers.
+  StackHandlerIterator handler_iterator(this, top_handler());
+  Object** next_parameter = parameters_base;
+  while (!handler_iterator.done()) {
+    // For each handler, visit the parameters down to the top of the handler
+    // and the handler itself.
+    StackHandler* handler = handler_iterator.handler();
+    Address handler_top = handler->address();
+    v->VisitPointers(next_parameter, reinterpret_cast<Object**>(handler_top));
+    handler->Iterate(v, code);
+    next_parameter =
+        reinterpret_cast<Object**>(handler_top + StackHandlerConstants::kSize);
+    handler_iterator.Advance();
+  }
+  // And visit all remaining parameters.
+  v->VisitPointers(next_parameter, parameters_limit);
 
   // Visit pointer spill slots and locals.
   for (unsigned index = 0; index < stack_slots; index++) {
@@ -878,6 +886,7 @@ void OptimizedFrame::Summarize(List<FrameSummary>* frames) {
       BailoutId ast_id = BailoutId(it.Next());
       JSFunction* function = LiteralAt(literal_array, it.Next());
       it.Next();  // Skip height.
+      it.Next();  // Skip handler count.
 
       // The translation commands are ordered and the receiver is always
       // at the first position. Since we are always at a call when we need
@@ -1002,6 +1011,7 @@ void OptimizedFrame::GetFunctions(List<JSFunction*>* functions) {
       it.Next();  // Skip ast id.
       JSFunction* function = LiteralAt(literal_array, it.Next());
       it.Next();  // Skip height.
+      it.Next();  // Skip handler count;
       functions->Add(function);
     } else {
       // Skip over operands to advance to the next opcode.