Mesa (master): radeonsi: Use param export count from si_llvm_export_vs in si_shader_vs

[Michel Dänzer]

Module: Mesa
Branch: master
Commit: 248b26429f52d0f19949a083aa3e0aeebcbe2138
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=248b26429f52d0f19949a083aa3e0aeebcbe2138

Author: Michel Dänzer <michel.daenzer at amd.com>
Date:   Mon Jul  6 17:23:07 2015 +0900

radeonsi: Use param export count from si_llvm_export_vs in si_shader_vs

This eliminates the error prone logic in si_shader_vs recalculating this
value.

It also fixes TGSI_SEMANTIC_CLIPDIST outputs incorrectly not being
counted for VS exports. They need to be counted because they are passed
to the pixel shader as parameters as well.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91193
Reviewed-by: Marek Olšák <marek.olsak at amd.com>

---

 src/gallium/drivers/radeonsi/si_shader.c        |    2 ++
 src/gallium/drivers/radeonsi/si_shader.h        |    1 +
 src/gallium/drivers/radeonsi/si_state_shaders.c |   25 +++--------------------
 3 files changed, 6 insertions(+), 22 deletions(-)

diff --git a/src/gallium/drivers/radeonsi/si_shader.c b/src/gallium/drivers/radeonsi/si_shader.c
index 4d97b58..753b238 100644
--- a/src/gallium/drivers/radeonsi/si_shader.c
+++ b/src/gallium/drivers/radeonsi/si_shader.c
@@ -1218,6 +1218,8 @@ handle_semantic:
 		}
 	}
 
+	shader->nr_param_exports = param_count;
+
 	/* We need to add the position output manually if it's missing. */
 	if (!pos_args[0][0]) {
 		pos_args[0][0] = lp_build_const_int32(base->gallivm, 0xf); /* writemask */
diff --git a/src/gallium/drivers/radeonsi/si_shader.h b/src/gallium/drivers/radeonsi/si_shader.h
index b4339ae..8d309b4 100644
--- a/src/gallium/drivers/radeonsi/si_shader.h
+++ b/src/gallium/drivers/radeonsi/si_shader.h
@@ -165,6 +165,7 @@ struct si_shader {
 
 	bool			uses_instanceid;
 	unsigned		nr_pos_exports;
+	unsigned		nr_param_exports;
 	bool			is_gs_copy_shader;
 	bool			dx10_clamp_mode; /* convert NaNs to 0 */
 };
diff --git a/src/gallium/drivers/radeonsi/si_state_shaders.c b/src/gallium/drivers/radeonsi/si_state_shaders.c
index eef3baa..a842d9d 100644
--- a/src/gallium/drivers/radeonsi/si_state_shaders.c
+++ b/src/gallium/drivers/radeonsi/si_state_shaders.c
@@ -148,10 +148,9 @@ static void si_shader_gs(struct si_shader *shader)
 
 static void si_shader_vs(struct si_shader *shader)
 {
-	struct tgsi_shader_info *info = &shader->selector->info;
 	struct si_pm4_state *pm4;
 	unsigned num_sgprs, num_user_sgprs;
-	unsigned nparams, i, vgpr_comp_cnt;
+	unsigned nparams, vgpr_comp_cnt;
 	uint64_t va;
 	unsigned window_space =
 	   shader->selector->info.properties[TGSI_PROPERTY_VS_WINDOW_SPACE_POSITION];
@@ -180,26 +179,8 @@ static void si_shader_vs(struct si_shader *shader)
 	}
 	assert(num_sgprs <= 104);
 
-	/* Certain attributes (position, psize, etc.) don't count as params.
-	 * VS is required to export at least one param and r600_shader_from_tgsi()
-	 * takes care of adding a dummy export.
-	 */
-	for (nparams = 0, i = 0 ; i < info->num_outputs; i++) {
-		switch (info->output_semantic_name[i]) {
-		case TGSI_SEMANTIC_CLIPVERTEX:
-		case TGSI_SEMANTIC_CLIPDIST:
-		case TGSI_SEMANTIC_CULLDIST:
-		case TGSI_SEMANTIC_POSITION:
-		case TGSI_SEMANTIC_PSIZE:
-		case TGSI_SEMANTIC_EDGEFLAG:
-			break;
-		default:
-			nparams++;
-		}
-	}
-	if (nparams < 1)
-		nparams = 1;
-
+	/* VS is required to export at least one param. */
+	nparams = MAX2(shader->nr_param_exports, 1);
 	si_pm4_set_reg(pm4, R_0286C4_SPI_VS_OUT_CONFIG,
 		       S_0286C4_VS_EXPORT_COUNT(nparams - 1));