nir/find_array_copies: Reject copies with mismatched lengths

copy_deref for wildcard dereferences requires the same
arrays lengths otherwise it leads to a crash in optimizations
like 'nir_opt_copy_prop_vars' because these optimizations expect
'copy_deref' just for arrays with the same lengths.

v2: check was moved to 'try_match_deref' to fix aoa cases
                 (Jason Ekstrand <jason@jlekstrand.net>)
v3: -fixed comment
    -the condition merged with other one
                 (Jason Ekstrand <jason@jlekstrand.net>)

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111286
Signed-off-by: Andrii Simiklit <andrii.simiklit@globallogic.com>
This commit is contained in:
Andrii Simiklit 2019-08-07 13:56:38 +03:00 committed by Jason Ekstrand
parent c4a4f3db5a
commit ff2225cf88
1 changed files with 8 additions and 4 deletions

View File

@ -260,7 +260,8 @@ clobber(struct match_node *node, struct match_state *state)
static bool
try_match_deref(nir_deref_path *base_path, int *path_array_idx,
nir_deref_path *deref_path, int arr_idx)
nir_deref_path *deref_path, int arr_idx,
nir_deref_instr *dst)
{
for (int i = 0; ; i++) {
nir_deref_instr *b = base_path->path[i];
@ -292,11 +293,13 @@ try_match_deref(nir_deref_path *base_path, int *path_array_idx,
/* If we don't have an index into the path yet or if this entry in
* the path is at the array index, see if this is a candidate. We're
* looking for an index which is zero in the base deref and arr_idx
* in the search deref.
* in the search deref and has a matching array size.
*/
if ((*path_array_idx < 0 || *path_array_idx == i) &&
const_b_idx && b_idx == 0 &&
const_d_idx && d_idx == arr_idx) {
const_d_idx && d_idx == arr_idx &&
glsl_get_length(nir_deref_instr_parent(b)->type) ==
glsl_get_length(nir_deref_instr_parent(dst)->type)) {
*path_array_idx = i;
continue;
}
@ -398,7 +401,8 @@ handle_write(nir_deref_instr *dst, nir_deref_instr *src,
nir_deref_path_init(&src_path, src, state->dead_ctx);
bool result = try_match_deref(&dst_node->first_src_path,
&dst_node->src_wildcard_idx,
&src_path, dst_node->next_array_idx);
&src_path, dst_node->next_array_idx,
*instr);
nir_deref_path_finish(&src_path);
if (!result)
goto reset;