From: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Date: Thu, 11 Jun 2020 14:27:17 +0000 (+0200)
Subject: radv: compute CB_SHADER_MASK from the fragment shader outputs
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=70cc80805ce5b027bece7334349ae8b028bf2862;p=mesa.git

radv: compute CB_SHADER_MASK from the fragment shader outputs

The fragment shader doesn't necessarily output the number of components
expected by the target format.

Fixes new dEQP-VK.draw.output_location.*.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5427>
---

diff --git a/src/amd/vulkan/radv_pipeline.c b/src/amd/vulkan/radv_pipeline.c
index 76244ecf503..fcc23aacd37 100644
--- a/src/amd/vulkan/radv_pipeline.c
+++ b/src/amd/vulkan/radv_pipeline.c
@@ -530,7 +530,6 @@ radv_pipeline_compute_spi_color_formats(struct radv_pipeline *pipeline,
 	if (blend->mrt0_is_dual_src)
 		col_format |= (col_format & 0xf) << 4;
 
-	blend->cb_shader_mask = ac_get_cb_shader_mask(col_format);
 	blend->spi_shader_col_format = col_format;
 }
 
@@ -5119,6 +5118,11 @@ radv_pipeline_init(struct radv_pipeline *pipeline,
 			blend.spi_shader_col_format = V_028714_SPI_SHADER_32_R;
 	}
 
+	blend.cb_shader_mask = ps->info.ps.cb_shader_mask;
+	if (blend.mrt0_is_dual_src) {
+		blend.cb_shader_mask |= (blend.cb_shader_mask & 0xf) << 4;
+	}
+
 	if (extra &&
 	    (extra->custom_blend_mode == V_028808_CB_ELIMINATE_FAST_CLEAR ||
 	     extra->custom_blend_mode == V_028808_CB_FMASK_DECOMPRESS ||
diff --git a/src/amd/vulkan/radv_shader.h b/src/amd/vulkan/radv_shader.h
index 7a621f732ef..ee4b01a34c2 100644
--- a/src/amd/vulkan/radv_shader.h
+++ b/src/amd/vulkan/radv_shader.h
@@ -310,6 +310,7 @@ struct radv_shader_info {
 		uint32_t explicit_shaded_mask;
 		uint32_t float16_shaded_mask;
 		uint32_t num_interp;
+		uint32_t cb_shader_mask;
 		bool can_discard;
 		bool early_fragment_test;
 		bool post_depth_coverage;
diff --git a/src/amd/vulkan/radv_shader_info.c b/src/amd/vulkan/radv_shader_info.c
index c7e26ba176f..dc4aea1d219 100644
--- a/src/amd/vulkan/radv_shader_info.c
+++ b/src/amd/vulkan/radv_shader_info.c
@@ -537,6 +537,17 @@ gather_info_output_decl_ps(const nir_shader *nir, const nir_variable *var,
 	default:
 		break;
 	}
+
+	if (idx >= FRAG_RESULT_DATA0 && idx <= FRAG_RESULT_DATA7) {
+		unsigned num_components = glsl_get_component_slots(glsl_without_array(var->type));
+		unsigned num_slots = glsl_count_attribute_slots(var->type, false);
+		unsigned write_mask = (1 << num_components) - 1;
+		unsigned slot = idx - FRAG_RESULT_DATA0;
+
+		for (unsigned i = 0; i < num_slots; i++) {
+			info->ps.cb_shader_mask |= write_mask << ((slot + i) * 4);
+		}
+	}
 }
 
 static void
@@ -834,4 +845,18 @@ radv_nir_shader_info_pass(const struct nir_shader *nir,
 	}
 
 	info->float_controls_mode = nir->info.float_controls_execution_mode;
+
+	if (nir->info.stage == MESA_SHADER_FRAGMENT) {
+		/* If the i-th output is used, all previous outputs must be
+		 * non-zero to match the target format.
+		 * TODO: compact MRT to avoid holes and to remove this
+		 * workaround.
+		 */
+		unsigned num_targets = (util_last_bit(info->ps.cb_shader_mask) + 3) / 4;
+		for (unsigned i = 0; i < num_targets; i++) {
+			if (!(info->ps.cb_shader_mask & (0xf << (i * 4)))) {
+				info->ps.cb_shader_mask |= 0xf << (i * 4);
+			}
+		}
+	}
 }