Indirectly dispatch all backtracking jumps through the same block.

runtime/vm/intermediate_language.h

Index: runtime/vm/intermediate_language.h
diff --git a/runtime/vm/intermediate_language.h b/runtime/vm/intermediate_language.h
index 0f0cfdb8d13eaff760112adcd63f7464f7e50684..743314e72025aea46a76a0253bb416cf06b76606 100644
--- a/runtime/vm/intermediate_language.h
+++ b/runtime/vm/intermediate_language.h
@@ -2227,17 +2227,7 @@ class IndirectGotoInstr : public TemplateInstruction<1, NoThrow> {
   virtual void PrintTo(BufferFormatter* f) const;
 
   const GrowableObjectArray& offsets() const { return offsets_; }
-  void SetOffsetCount(Isolate* isolate, intptr_t count) {
-    if (offsets_.Capacity() < count) {
-      offsets_.Grow(count, Heap::kOld);
-    }
-    if (offsets_.Length() < count) {
-      offsets_.SetLength(count);
-    }
-  }
-  void SetOffsetAt(Isolate* isolate, intptr_t index, intptr_t offset) {
-    offsets_.SetAt(index, Smi::ZoneHandle(isolate, Smi::New(offset)));
-  }
+  void ComputeOffsetTable(Isolate* isolate);
 
  private:
   GrowableArray<TargetEntryInstr*> successors_;