From f6008645f6e2bad4aeb7bdacfbddbf0217754b3c Mon Sep 17 00:00:00 2001
From: Emma Anholt <emma@anholt.net>
Date: Tue, 6 Jan 2026 12:59:25 -0800
Subject: [PATCH] nir: Fix constant evaluation of non-32-bit bitfield_extract.

Caught by nir_opt_algebraic_pattern_tests.

Fixes: 226b0e28dbe9 ("nir: generalize bitfield insert/extract sizes")
Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/39076>
---
 src/compiler/nir/nir_opcodes.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/compiler/nir/nir_opcodes.py b/src/compiler/nir/nir_opcodes.py
index 77ceacf83be..46ac53905b7 100644
--- a/src/compiler/nir/nir_opcodes.py
+++ b/src/compiler/nir/nir_opcodes.py
@@ -1169,7 +1169,7 @@ unsigned base = src0;
 int offset = src1, bits = src2;
 if (bits == 0) {
    dst = 0;
-} else if (bits < 0 || offset < 0 || offset + bits > 32) {
+} else if (bits < 0 || offset < 0 || offset + bits > bit_size) {
    dst = 0; /* undefined per the spec */
 } else {
    dst = (base >> offset) & ((1ull << bits) - 1);
@@ -1181,7 +1181,7 @@ int base = src0;
 int offset = src1, bits = src2;
 if (bits == 0) {
    dst = 0;
-} else if (offset < 0 || bits < 0 || offset + bits > 32) {
+} else if (offset < 0 || bits < 0 || offset + bits > bit_size) {
    dst = 0;
 } else {
    dst = (base << (32 - offset - bits)) >> (32 - bits); /* use sign-extending shift */