Debugger: use debug break slots to break at function exit.

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index e53df91d0ba67f99ba9bb1f422a4b68ff9fed72d..6b65537759dde7388ff8f34a63db62f836b5c96c 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -10763,11 +10763,9 @@ void ObjectVisitor::VisitCell(RelocInfo* rinfo) {
 
 
 void ObjectVisitor::VisitDebugTarget(RelocInfo* rinfo) {
-  DCHECK((RelocInfo::IsJSReturn(rinfo->rmode()) &&
-          rinfo->IsPatchedReturnSequence()) ||
-         (RelocInfo::IsDebugBreakSlot(rinfo->rmode()) &&
-          rinfo->IsPatchedDebugBreakSlotSequence()));
-  Object* target = Code::GetCodeFromTargetAddress(rinfo->call_address());
+  DCHECK(RelocInfo::IsDebugBreakSlot(rinfo->rmode()) &&
+         rinfo->IsPatchedDebugBreakSlotSequence());
+  Object* target = Code::GetCodeFromTargetAddress(rinfo->debug_call_address());
   Object* old_target = target;
   VisitPointer(&target);
   CHECK_EQ(target, old_target);  // VisitPointer doesn't change Code* *target.
@@ -10811,7 +10809,7 @@ void Code::InvalidateEmbeddedObjects() {
 
 void Code::Relocate(intptr_t delta) {
   for (RelocIterator it(this, RelocInfo::kApplyMask); !it.done(); it.next()) {
-    it.rinfo()->apply(delta, SKIP_ICACHE_FLUSH);
+    it.rinfo()->apply(delta);
   }
   CpuFeatures::FlushICache(instruction_start(), instruction_size());
 }
@@ -10864,7 +10862,7 @@ void Code::CopyFrom(const CodeDesc& desc) {
       Code* code = Code::cast(*p);
       it.rinfo()->set_code_age_stub(code, SKIP_ICACHE_FLUSH);
     } else {
-      it.rinfo()->apply(delta, SKIP_ICACHE_FLUSH);
+      it.rinfo()->apply(delta);
     }
   }
   CpuFeatures::FlushICache(instruction_start(), instruction_size());