From feffd0e445a375aa23d15bf27a0ba5a3d53d3e8b Mon Sep 17 00:00:00 2001
From: Emma Anholt <emma@anholt.net>
Date: Tue, 23 Dec 2025 15:57:03 -0800
Subject: [PATCH] nir: Avoid UB of (int)0xff << 24 evaluating usadd_4x8_vc4.

Caught by UBSan on introduction of nir_opt_algebraic_pattern_test.

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/39184>
---
 src/compiler/nir/nir_opcodes.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/compiler/nir/nir_opcodes.py b/src/compiler/nir/nir_opcodes.py
index 4f4ee3d6ebc..a70b106af40 100644
--- a/src/compiler/nir/nir_opcodes.py
+++ b/src/compiler/nir/nir_opcodes.py
@@ -1502,7 +1502,7 @@ if (!isnormal(dst))
 binop("usadd_4x8_vc4", tint32, _2src_commutative + associative, """
 dst = 0;
 for (int i = 0; i < 32; i += 8) {
-   dst |= MIN2(((src0 >> i) & 0xff) + ((src1 >> i) & 0xff), 0xff) << i;
+   dst |= (uint32_t)MIN2(((src0 >> i) & 0xff) + ((src1 >> i) & 0xff), 0xff) << i;
 }
 """)