VM: Add smi fast path operations for precompiled code

runtime/vm/object.h

Index: runtime/vm/object.h
diff --git a/runtime/vm/object.h b/runtime/vm/object.h
index 3c2b7c20a13e2194fcb94969c143bc3a61492201..188f9f970d3fe81075f9b9fbfe50a1b4952eda10 100644
--- a/runtime/vm/object.h
+++ b/runtime/vm/object.h
@@ -4164,10 +4164,10 @@ class Stackmap : public Object {
     StoreNonPointer(&raw_ptr()->pc_offset_, value);
   }
 
-  intptr_t RegisterBitCount() const { return raw_ptr()->register_bit_count_; }
-  void SetRegisterBitCount(intptr_t register_bit_count) const {
-    ASSERT(register_bit_count < kMaxInt32);
-    StoreNonPointer(&raw_ptr()->register_bit_count_, register_bit_count);
+  intptr_t SlowPathBitCount() const { return raw_ptr()->slow_path_bit_count_; }
+  void SetSlowPathBitCount(intptr_t bit_count) const {
+    ASSERT(bit_count < kMaxInt32);
+    StoreNonPointer(&raw_ptr()->slow_path_bit_count_, bit_count);
   }
 
   bool Equals(const Stackmap& other) const {