src/hotspot/cpu/x86/gc/shared/cardTableBarrierSetAssembler_x86.cpp

@@ -116,22 +116,28 @@
  }
  
  void CardTableBarrierSetAssembler::oop_store_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type,
                                                  Address dst, Register val, Register tmp1, Register tmp2, Register tmp3) {
    bool in_heap = (decorators & IN_HEAP) != 0;
- 
    bool is_array = (decorators & IS_ARRAY) != 0;
    bool on_anonymous = (decorators & ON_UNKNOWN_OOP_REF) != 0;
    bool precise = is_array || on_anonymous;
  
    bool needs_post_barrier = val != noreg && in_heap;
  
    BarrierSetAssembler::store_at(masm, decorators, type, dst, val, noreg, noreg, noreg);
    if (needs_post_barrier) {
      // flatten object address if needed
      if (!precise || (dst.index() == noreg && dst.disp() == 0)) {
-       store_check(masm, dst.base(), dst);
+       if (tmp3 != noreg) {
+         // Called by MacroAssembler::pack_inline_helper. We cannot corrupt the dst.base() register
+         __ movptr(tmp3, dst.base());
+         store_check(masm, tmp3, dst);
+       } else {
+         // It's OK to corrupt the dst.base() register.
+         store_check(masm, dst.base(), dst);
+       }
      } else {
        __ lea(tmp1, dst);
        store_check(masm, tmp1, dst);
      }
    }