radv: fix alpha-to-coverage when there is unused color attachments
When alphaToCoverage is enabled, we should always write the alpha
channel of MRT0 if it's unused. This now matches RadeonSI.
This fixes the new CTS:
dEQP-VK.pipeline.multisample.alpha_to_coverage_unused_attachment.samples_*.alpha_invisible
Cc: 19.0 19.1 <mesa-stable@lists.freedesktop.org>
Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-By: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl
(cherry picked from commit 91aa25f4625014ddf194578fc1c1d0a505e5f8db)
diff --git a/src/amd/vulkan/radv_pipeline.c b/src/amd/vulkan/radv_pipeline.c
index f25a5f5..773ccd8 100644
--- a/src/amd/vulkan/radv_pipeline.c
+++ b/src/amd/vulkan/radv_pipeline.c
@@ -524,7 +524,7 @@
col_format |= cf << (4 * i);
}
- if (!col_format && blend->need_src_alpha & (1 << 0)) {
+ if (!(col_format & 0xf) && blend->need_src_alpha & (1 << 0)) {
/* When a subpass doesn't have any color attachments, write the
* alpha channel of MRT0 when alpha coverage is enabled because
* the depth attachment needs it.
