[Mesa-dev] [PATCH 1/3] nir: fix algebraic optimizations

[Connor Abbott]

From: Connor Abbott <cwabbott0 at gmail.com>

The optimizations are only valid for 32-bit integers. They were
mistakenly firing for 64-bit integers as well.

Cc: mesa-stable at lists.freedesktop.org
---
 src/compiler/nir/nir_opt_algebraic.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/compiler/nir/nir_opt_algebraic.py b/src/compiler/nir/nir_opt_algebraic.py
index df58542..ad75228 100644
--- a/src/compiler/nir/nir_opt_algebraic.py
+++ b/src/compiler/nir/nir_opt_algebraic.py
@@ -250,8 +250,8 @@ optimizations = [
    (('ishr', a, 0), a),
    (('ushr', 0, a), 0),
    (('ushr', a, 0), a),
-   (('iand', 0xff, ('ushr', a, 24)), ('ushr', a, 24)),
-   (('iand', 0xffff, ('ushr', a, 16)), ('ushr', a, 16)),
+   (('iand', 0xff, ('ushr at 32', a, 24)), ('ushr', a, 24)),
+   (('iand', 0xffff, ('ushr at 32', a, 16)), ('ushr', a, 16)),
    # Exponential/logarithmic identities
    (('~fexp2', ('flog2', a)), a), # 2^lg2(a) = a
    (('~flog2', ('fexp2', a)), a), # lg2(2^a) = a
-- 
2.9.4