nir/unsigned_upper_bound: don't require dominance metadata

Instead, determine if it's a merge or loop exit phi.

Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9808>

2 files changed, 2 insertions, 11 deletions

diff --git a/src/compiler/nir/nir_opt_offsets.c b/src/compiler/nir/nir_opt_offsets.c
index 4047ee5daae..88b7b2a2862 100644
--- a/src/compiler/nir/nir_opt_offsets.c
+++ b/src/compiler/nir/nir_opt_offsets.c
@@ -51,9 +51,6 @@ try_extract_const_addition(nir_builder *b, nir_instr *instr, opt_offsets_state *
          state->range_ht = _mesa_pointer_hash_table_create(NULL);
       }
 
-      /* Dominance metadata is needed by nir_unsigned_upper_bound to chase phis */
-      nir_metadata_require(b->impl, nir_metadata_dominance);
-
       /* Check if there can really be an unsigned wrap. */
       nir_ssa_scalar src0 = {alu->src[0].src.ssa, 0};
       nir_ssa_scalar src1 = {alu->src[1].src.ssa, 0};
diff --git a/src/compiler/nir/nir_range_analysis.c b/src/compiler/nir/nir_range_analysis.c
index 1d7eb99283e..6936b49c9de 100644
--- a/src/compiler/nir/nir_range_analysis.c
+++ b/src/compiler/nir/nir_range_analysis.c
@@ -1402,16 +1402,10 @@ nir_unsigned_upper_bound(nir_shader *shader, struct hash_table *range_ht,
    }
 
    if (scalar.def->parent_instr->type == nir_instr_type_phi) {
-      bool cyclic = false;
-      nir_foreach_phi_src(src, nir_instr_as_phi(scalar.def->parent_instr)) {
-         if (nir_block_dominates(scalar.def->parent_instr->block, src->pred)) {
-            cyclic = true;
-            break;
-         }
-      }
+      nir_cf_node *prev = nir_cf_node_prev(&scalar.def->parent_instr->block->cf_node);
 
       uint32_t res = 0;
-      if (cyclic) {
+      if (!prev || prev->type == nir_cf_node_block) {
          _mesa_hash_table_insert(range_ht, key, (void*)(uintptr_t)max);
 
          struct set *visited = _mesa_pointer_set_create(NULL);