From e41eb8950b0c8bb19f0298fe387fe31a0c4fc343 Mon Sep 17 00:00:00 2001
From: "Thomas H.P. Andersen" <phomes@gmail.com>
Date: Tue, 29 Jun 2021 00:54:40 +0200
Subject: [PATCH] nir/ifind_msb_rev: fix input check

ifind_msb_rev was introduced in a5747f8ab357ff00c630b937b221e5fb59d90289.

ifind_msb_rev guards against src0 being both 0 or -1 at the same time.
That is always true. This patch changes it to check for those values
individually.

Spotted from a compile warning.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>

Fixes: a5747f8ab35 (\"nir: add opcodes for *find_msb_rev and lowering\")
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11630>
(cherry picked from commit ffea62260415c9e1b5c8fa076ac0285c0145447e)
---
 .pick_status.json               | 2 +-
 src/compiler/nir/nir_opcodes.py | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/.pick_status.json b/.pick_status.json
index aa65ffb077d..94f67c1f659 100644
--- a/.pick_status.json
+++ b/.pick_status.json
@@ -4036,7 +4036,7 @@
         "description": "nir/ifind_msb_rev: fix input check",
         "nominated": true,
         "nomination_type": 1,
-        "resolution": 0,
+        "resolution": 1,
         "main_sha": null,
         "because_sha": "a5747f8ab357ff00c630b937b221e5fb59d90289"
     },
diff --git a/src/compiler/nir/nir_opcodes.py b/src/compiler/nir/nir_opcodes.py
index 88194f762f0..b977e17a8e8 100644
--- a/src/compiler/nir/nir_opcodes.py
+++ b/src/compiler/nir/nir_opcodes.py
@@ -489,7 +489,7 @@ for (int bit = 31; bit >= 0; bit--) {
 
 unop_convert("ifind_msb_rev", tint32, tuint, """
 dst = -1;
-if (src0 != 0 || src0 != -1) {
+if (src0 != 0 && src0 != -1) {
    for (int bit = 0; bit < 31; bit++) {
       /* If src0 < 0, we're looking for the first 0 bit.
        * if src0 >= 0, we're looking for the first 1 bit.