Fix stub frame walking: when materializing the frame content during deoptimization, the stack is no…

runtime/vm/raw_object.cc

Index: runtime/vm/raw_object.cc
diff --git a/runtime/vm/raw_object.cc b/runtime/vm/raw_object.cc
index 98553cd9adb70b4d858ff4aa5cd41ba695b4991a..437ab7e7225eda6d2d7cddf17f3ec18e532cc35a 100644
--- a/runtime/vm/raw_object.cc
+++ b/runtime/vm/raw_object.cc
@@ -535,11 +535,8 @@ intptr_t RawCode::VisitCodePointers(RawCode* raw_obj,
 
   RawCode* obj = raw_obj->ptr();
   intptr_t length = Code::PtrOffBits::decode(obj->state_bits_);
-#if defined(TARGET_ARCH_IA32)
-  // On IA32 only we embed pointers to objects directly in the generated
-  // instructions. The variable portion of a Code object describes where to
-  // find those pointers for tracing.
   if (Code::AliveBit::decode(obj->state_bits_)) {
+    // Also visit all the embedded pointers in the corresponding instructions.
     uword entry_point = reinterpret_cast<uword>(obj->instructions_->ptr()) +
         Instructions::HeaderSize();
     for (intptr_t i = 0; i < length; i++) {
@@ -549,12 +546,6 @@ intptr_t RawCode::VisitCodePointers(RawCode* raw_obj,
     }
   }
   return Code::InstanceSize(length);
-#else
-  // On all other architectures, objects are referenced indirectly through
-  // either an ObjectPool or Thread.
-  ASSERT(length == 0);
-  return Code::InstanceSize(0);
-#endif
 }