nir/find_array_copies: Use correct parent array length

instr->type is the type of the array element, not the type of the array
being dereferenced. Rather than fishing out the parent type, just use
parent->num_children which should be the length plus 1. While we're here
add another assert for the issue fixed by the previous commit.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111251
Fixes: 156306e5e62 ("nir/find_array_copies: Handle wildcards and overlapping copies")
Reviewed-by: Jason Ekstrand <[email protected]>

1 files changed, 3 insertions, 2 deletions

diff --git a/src/compiler/nir/nir_opt_find_array_copies.c b/src/compiler/nir/nir_opt_find_array_copies.c
index 28f77335d99..63609715c3a 100644
--- a/src/compiler/nir/nir_opt_find_array_copies.c
+++ b/src/compiler/nir/nir_opt_find_array_copies.c
@@ -100,14 +100,15 @@ node_for_deref(nir_deref_instr *instr, struct match_node *parent,
    }
 
    case nir_deref_type_array_wildcard:
-      idx = glsl_get_length(instr->type);
+      idx = parent->num_children - 1;
       break;
 
    case nir_deref_type_array:
       if (nir_src_is_const(instr->arr.index)) {
          idx = nir_src_as_uint(instr->arr.index);
+         assert(idx < parent->num_children - 1);
       } else {
-         idx = glsl_get_length(instr->type);
+         idx = parent->num_children - 1;
       }
       break;