Emit sunk IR_NEWREF only once per key on snapshot replay.

Thanks to Sergey Kaplun and Peter Cawley. #1128

diff --git a/src/lj_snap.c b/src/lj_snap.c
index a6cd93d49f85178df4ee19ed7f57a89277e057e9..5a5c481bc1285544c2b3d442c2f9557b983c6f9b 100644 (file)
--- a/src/lj_snap.c
+++ b/src/lj_snap.c
@@ -575,9 +575,21 @@ void lj_snap_replay(jit_State *J, GCtrace *T)
                if (irr->o == IR_HREFK || irr->o == IR_AREF) {
                  IRIns *irf = &T->ir[irr->op1];
                  tmp = emitir(irf->ot, tmp, irf->op2);
+               } else if (irr->o == IR_NEWREF) {
+                 IRRef allocref = tref_ref(tr);
+                 IRRef keyref = tref_ref(key);
+                 IRRef newref_ref = J->chain[IR_NEWREF];
+                 IRIns *newref = &J->cur.ir[newref_ref];
+                 lua_assert(irref_isk(keyref));
+                 if (newref_ref > allocref && newref->op2 == keyref) {
+                   lua_assert(newref->op1 == allocref);
+                   tmp = newref_ref;
+                   goto skip_newref;
+                 }
                }
              }
              tmp = emitir(irr->ot, tmp, key);
+           skip_newref:
              val = snap_pref(J, T, map, nent, seen, irs->op2);
              if (val == 0) {
                IRIns *irc = &T->ir[irs->op2];