Mesa (master): aco: don't move memory accesses to before control barriers

[GitLab Mirror]

Module: Mesa
Branch: master
Commit: 7b4c24eb679e248894751f30e2ea842dcf3f21f3
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=7b4c24eb679e248894751f30e2ea842dcf3f21f3

Author: Rhys Perry <pendingchaos02 at gmail.com>
Date:   Tue Aug  4 19:20:21 2020 +0100

aco: don't move memory accesses to before control barriers

Fixes random failures of dEQP-VK.image.qualifiers.volatile.cube_array.r32i
and similar tests on Vega.

fossil-db (Navi):
Totals from 6 (0.00% of 135946) affected shaders:
VMEM: 1218 -> 1110 (-8.87%); split: +2.46%, -11.33%
SMEM: 174 -> 189 (+8.62%)
Copies: 84 -> 87 (+3.57%)

Signed-off-by: Rhys Perry <pendingchaos02 at gmail.com>
Reviewed-by: Daniel Schürmann <daniel at schuermann.dev>
Fixes: cd392a10d05 ('radv/aco,aco: use scoped barriers')
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6174>

---

 src/amd/compiler/aco_scheduler.cpp | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/amd/compiler/aco_scheduler.cpp b/src/amd/compiler/aco_scheduler.cpp
index 52b64f02116..9d6810672b5 100644
--- a/src/amd/compiler/aco_scheduler.cpp
+++ b/src/amd/compiler/aco_scheduler.cpp
@@ -495,6 +495,12 @@ HazardResult perform_hazard_query(hazard_query *query, Instruction *instr, bool
    if (first->bar_classes && second->bar_classes)
       return hazard_fail_barrier;
 
+   /* Don't move memory accesses to before control barriers. I don't think
+    * this is necessary for the Vulkan memory model, but it might be for GLSL450. */
+   unsigned control_classes = storage_buffer | storage_atomic_counter | storage_image | storage_shared;
+   if (first->has_control_barrier && ((second->access_atomic | second->access_relaxed) & control_classes))
+      return hazard_fail_barrier;
+
    /* don't move memory loads/stores past potentially aliasing loads/stores */
    unsigned aliasing_storage = instr->format == Format::SMEM ?
                                query->aliasing_storage_smem :