Fix precondition check for NEWREF.

A check for nil value is not enough. Must check for ptr == niltv.

diff --git a/src/lj_record.c b/src/lj_record.c
index 540686979a52d6645b62304416dde3fbd71a013f..29c024bfece663faacf36366183ae6d69553e786 100644 (file)
--- a/src/lj_record.c
+++ b/src/lj_record.c
@@ -995,10 +995,10 @@ static TRef rec_idx(jit_State *J, RecordIndex *ix)
        cTValue *mo = lj_tab_getstr(mt, strref(J2G(J)->mmname[MM_newindex]));
        hasmm = mo && !tvisnil(mo);
       }
-      if (hasmm || oldv == niltvg(J2G(J)))
+      if (hasmm)
        emitir(IRTG(loadop, IRT_NIL), xref, 0);  /* Guard for nil value. */
       else if (xrefop == IR_HREF)
-       emitir(IRTG(IR_NE, IRT_PTR), xref, lj_ir_kptr(J, niltvg(J2G(J))));
+       emitir(IRTG(oldv == niltvg(J2G(J)) ? IR_EQ : IR_NE, IRT_PTR), xref, lj_ir_kptr(J, niltvg(J2G(J))));
       if (ix->idxchain && rec_mm_lookup(J, ix, MM_newindex)) { /* Metamethod? */
        lua_assert(hasmm);
        goto handlemm;