Mesa (master): util: Fix UBSan failure on _mesa_unorm_to_unorm.

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Module: Mesa
Branch: master
Commit: 05652703807758cb48a09cb6bbd29bacb0dfa870
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=05652703807758cb48a09cb6bbd29bacb0dfa870

Author: Eric Anholt <eric at anholt.net>
Date:   Wed Aug 12 14:30:18 2020 -0700

util: Fix UBSan failure on _mesa_unorm_to_unorm.

It complains about shifting 1<<31 being undefined, so make it a 1u.

Reviewed-by: Marek Olšák <marek.olsak at amd.com>
Acked-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer at amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6297>

---

 src/util/format/format_utils.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/util/format/format_utils.h b/src/util/format/format_utils.h
index e752bf2563a..fa1d30060d9 100644
--- a/src/util/format/format_utils.h
+++ b/src/util/format/format_utils.h
@@ -94,7 +94,7 @@ _mesa_unorm_to_unorm(unsigned x, unsigned src_bits, unsigned dst_bits)
    if (src_bits < dst_bits) {
       return EXTEND_NORMALIZED_INT(x, src_bits, dst_bits);
    } else if (src_bits > dst_bits) {
-      unsigned src_half = (1 << (src_bits - 1)) - 1;
+      unsigned src_half = (1u << (src_bits - 1)) - 1;
 
       if (src_bits + dst_bits > sizeof(x) * 8) {
          assert(src_bits + dst_bits <= sizeof(uint64_t) * 8);