For some R8 formats, it's useless to export two channels when no alpha blending is used. I assume the CB should automatically clamps its inputs.
29077 shaders in 15096 tests Totals: SGPRS: 1321106 -> 1320970 (-0.01 %) VGPRS: 935936 -> 935948 (0.00 %) Spilled SGPRs: 25186 -> 25204 (0.07 %) Code Size: 49813556 -> 49796944 (-0.03 %) bytes Max Waves: 242091 -> 242088 (-0.00 %) Totals from affected shaders: SGPRS: 170608 -> 170472 (-0.08 %) VGPRS: 99752 -> 99764 (0.01 %) Spilled SGPRs: 10377 -> 10395 (0.17 %) Code Size: 6332492 -> 6315880 (-0.26 %) bytes Max Waves: 12317 -> 12314 (-0.02 %) This helps some Rise Of Tomb Raider shaders, especially when an expcnt instruction is added between two MRT exports. Signed-off-by: Samuel Pitoiset <samuel.pitoi...@gmail.com> --- src/amd/vulkan/radv_pipeline.c | 27 ++++++++++++++++++++++----- 1 file changed, 22 insertions(+), 5 deletions(-) diff --git a/src/amd/vulkan/radv_pipeline.c b/src/amd/vulkan/radv_pipeline.c index 138e153f9a4..25281c3c6da 100644 --- a/src/amd/vulkan/radv_pipeline.c +++ b/src/amd/vulkan/radv_pipeline.c @@ -372,9 +372,10 @@ static bool is_dual_src(VkBlendFactor factor) } } -static unsigned si_choose_spi_color_format(VkFormat vk_format, - bool blend_enable, - bool blend_need_alpha) +static unsigned si_choose_spi_color_format(struct radv_device *device, + VkFormat vk_format, + bool blend_enable, + bool blend_need_alpha) { const struct vk_format_description *desc = vk_format_description(vk_format); unsigned format, ntype, swap; @@ -486,6 +487,20 @@ static unsigned si_choose_spi_color_format(VkFormat vk_format, unreachable("unhandled blend format"); } + if (device && /* NULL for internal meta formats */ + !device->physical_device->rbplus_allowed) { + /* Try to select better export formats for chips without Rb+. */ + if (desc->nr_channels == 1 && + desc->channel[0].size == 8 && + swap == V_028C70_SWAP_STD && /* R */ + !vk_format_is_srgb(vk_format)) { + /* Do not need to export two channels for some R8 + * formats when alpha blending isn't used. + */ + blend = normal = V_028714_SPI_SHADER_32_R; + } + } + if (blend_enable && blend_need_alpha) return blend_alpha; else if(blend_need_alpha) @@ -516,7 +531,8 @@ radv_pipeline_compute_spi_color_formats(struct radv_pipeline *pipeline, bool blend_enable = blend->blend_enable_4bit & (0xfu << (i * 4)); - cf = si_choose_spi_color_format(attachment->format, + cf = si_choose_spi_color_format(pipeline->device, + attachment->format, blend_enable, blend->need_src_alpha & (1 << i)); } @@ -586,7 +602,8 @@ const VkFormat radv_fs_key_format_exemplars[NUM_META_FS_KEYS] = { unsigned radv_format_meta_fs_key(VkFormat format) { - unsigned col_format = si_choose_spi_color_format(format, false, false); + unsigned col_format = + si_choose_spi_color_format(NULL, format, false, false); assert(col_format != V_028714_SPI_SHADER_32_AR); if (col_format >= V_028714_SPI_SHADER_32_AR) -- 2.20.1 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev