nir/validate: Only walk uses once

Ostensibly faster.

Signed-off-by: Alyssa Rosenzweig <alyssa@collabora.com>
Reviewed-by: Faith Ekstrand <faith.ekstrand@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/22343>

diff --git a/src/compiler/nir/nir_validate.c b/src/compiler/nir/nir_validate.c
index f051b2363217f8bc0bbb0127fdd3e5b2e9f83f4b..d343021a93caa7c0af0598b629e09315b0a3ce49 100644 (file)
--- a/src/compiler/nir/nir_validate.c
+++ b/src/compiler/nir/nir_validate.c
@@ -528,16 +528,17 @@ validate_deref_instr(nir_deref_instr *instr, validate_state *state)
     */
    validate_dest(&instr->dest, state, 0, 0);
 
-   /* Deref instructions as if conditions don't make sense because if
-    * conditions expect well-formed Booleans.  If you want to compare with
-    * NULL, an explicit comparison operation should be used.
-    */
-   validate_assert(state, !nir_ssa_def_used_by_if(&instr->dest.ssa));
-
    /* Certain modes cannot be used as sources for phi instructions because
     * way too many passes assume that they can always chase deref chains.
     */
-   nir_foreach_use(use, &instr->dest.ssa) {
+   nir_foreach_use_including_if(use, &instr->dest.ssa) {
+      /* Deref instructions as if conditions don't make sense because if
+       * conditions expect well-formed Booleans.  If you want to compare with
+       * NULL, an explicit comparison operation should be used.
+       */
+      if (!validate_assert(state, !use->is_if))
+         continue;
+
       if (use->parent_instr->type == nir_instr_type_phi) {
          validate_assert(state, !(instr->modes & (nir_var_shader_in |
                                                   nir_var_shader_out |