[Mesa-dev] [PATCH v2] radv/gfx10: fix VS input VGPRs with the legacy path

[Samuel Pitoiset]

For some reasons, InstanceID is VGPR3 although StepRate0 is set to 1.

v2: fix instanceID

Signed-off-by: Samuel Pitoiset <samuel.pitoiset at gmail.com>
---
 src/amd/vulkan/radv_nir_to_llvm.c | 12 +++++++++---
 src/amd/vulkan/radv_shader.c      |  2 +-
 2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/src/amd/vulkan/radv_nir_to_llvm.c b/src/amd/vulkan/radv_nir_to_llvm.c
index 336bae28614..cf73cdc692b 100644
--- a/src/amd/vulkan/radv_nir_to_llvm.c
+++ b/src/amd/vulkan/radv_nir_to_llvm.c
@@ -852,9 +852,15 @@ declare_vs_input_vgprs(struct radv_shader_context *ctx, struct arg_info *args)
 			}
 		} else {
 			if (ctx->ac.chip_class >= GFX10) {
-				add_arg(args, ARG_VGPR, ctx->ac.i32, NULL); /* user vgpr */
-				add_arg(args, ARG_VGPR, ctx->ac.i32, NULL); /* user vgpr */
-				add_arg(args, ARG_VGPR, ctx->ac.i32, &ctx->abi.instance_id);
+				if (ctx->options->key.vs_common_out.as_ngg) {
+					add_arg(args, ARG_VGPR, ctx->ac.i32, NULL); /* user vgpr */
+					add_arg(args, ARG_VGPR, ctx->ac.i32, NULL); /* user vgpr */
+					add_arg(args, ARG_VGPR, ctx->ac.i32, &ctx->abi.instance_id);
+				} else {
+					add_arg(args, ARG_VGPR, ctx->ac.i32, NULL); /* unused */
+					add_arg(args, ARG_VGPR, ctx->ac.i32, &ctx->vs_prim_id);
+					add_arg(args, ARG_VGPR, ctx->ac.i32, &ctx->abi.instance_id);
+				}
 			} else {
 				add_arg(args, ARG_VGPR, ctx->ac.i32, &ctx->abi.instance_id);
 				add_arg(args, ARG_VGPR, ctx->ac.i32, &ctx->vs_prim_id);
diff --git a/src/amd/vulkan/radv_shader.c b/src/amd/vulkan/radv_shader.c
index 3adaf52e152..3d1b56e7f60 100644
--- a/src/amd/vulkan/radv_shader.c
+++ b/src/amd/vulkan/radv_shader.c
@@ -765,7 +765,7 @@ static void radv_postprocess_config(const struct radv_physical_device *pdevice,
 			if (info->vs.export_prim_id) {
 				vgpr_comp_cnt = 2;
 			} else if (info->info.vs.needs_instance_id) {
-				vgpr_comp_cnt = 1;
+				vgpr_comp_cnt = pdevice->rad_info.chip_class >= GFX10 ? 3 : 1;
 			} else {
 				vgpr_comp_cnt = 0;
 			}
-- 
2.22.0