From 6e6e71ddf9e7356162206ace2009011a509527ea Mon Sep 17 00:00:00 2001
From: Iago Toral Quiroga <itoral@igalia.com>
Date: Fri, 5 Mar 2021 13:18:02 +0100
Subject: [PATCH] broadcom/compiler: fix flags check for ldvary merge
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

We were checking that the previous instruction doesn't write flags,
but we also need to check it doesn't read them.

Fixes: 1784dd22a32 ('broadcom/compiler: pipeline smooth ldvary sequences')
Reviewed-by: Alejandro Piñeiro <apinheiro@igalia.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9431>
---
 src/broadcom/compiler/qpu_schedule.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/broadcom/compiler/qpu_schedule.c b/src/broadcom/compiler/qpu_schedule.c
index 90dba7f48b0..bc0ade2cbf0 100644
--- a/src/broadcom/compiler/qpu_schedule.c
+++ b/src/broadcom/compiler/qpu_schedule.c
@@ -1644,6 +1644,8 @@ fixup_pipelined_ldvary(struct v3d_compile *c,
          */
         if (v3d_qpu_writes_flags(&prev->qpu))
                 return false;
+        if (v3d_qpu_reads_flags(&prev->qpu))
+                return false;
 
         /* Move the ldvary to the previous instruction and remove it from the
          * current one.