More completely fixed the 0-key thing.

Unfortunately this degrades hash table lookup performance by
about 8%, which affects the streaming benchmark for googlemessage1
by about 5%.  We could get this back at the cost of some memory,
but it would be nice to avoid that.

1 files changed, 1 insertions, 2 deletions

diff --git a/src/upb_table.h b/src/upb_table.h
index 1918e20..e667f0d 100644
--- a/src/upb_table.h
+++ b/src/upb_table.h
@@ -100,12 +100,11 @@ INLINE uint32_t upb_inttable_bucket(upb_inttable *t, upb_inttable_key_t k) {
  * ability to optimize. */
 INLINE void *upb_inttable_fastlookup(upb_inttable *t, uint32_t key,
                                      uint32_t entry_size) {
-  assert(key != 0);
   uint32_t bucket = upb_inttable_bucket(t, key);
   upb_inttable_entry *e;
   do {
     e = (upb_inttable_entry*)UPB_INDEX(t->t.entries, bucket-1, entry_size);
-    if(e->key == key) return e;
+    if(e->key == key && e->has_entry) return e;
   } while((bucket = e->next) != UPB_END_OF_CHAIN);
   return NULL;  /* Not found. */
 }