radv/gfx10: make use the output usage mask when exporting NGG GS params

It shouldn't matter much because output varyings should have been
compacted during NIR shader linking but it mirrors what the driver
does when emitting NGG GS vertex parameters.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>

diff --git a/src/amd/vulkan/radv_nir_to_llvm.c b/src/amd/vulkan/radv_nir_to_llvm.c
index 10cc82eb8d9ca810c8a34ae83830fe217ace441e..0c13860fe281000cda00f7ccdb43905f884b093b 100644 (file)
--- a/src/amd/vulkan/radv_nir_to_llvm.c
+++ b/src/amd/vulkan/radv_nir_to_llvm.c
@@ -3489,16 +3489,21 @@ static void gfx10_ngg_gs_emit_epilogue_2(struct radv_shader_context *ctx)
                unsigned out_idx = 0;
                gep_idx[1] = ctx->ac.i32_0;
                for (unsigned i = 0; i < AC_LLVM_MAX_OUTPUTS; ++i) {
+                       unsigned output_usage_mask =
+                               ctx->shader_info->gs.output_usage_mask[i];
+                       int length = util_last_bit(output_usage_mask);
+
                        if (!(ctx->output_mask & (1ull << i)))
                                continue;
 
                        outputs[noutput].slot_name = i;
                        outputs[noutput].slot_index = i == VARYING_SLOT_CLIP_DIST1;
-
-                       outputs[noutput].usage_mask = ctx->shader_info->gs.output_usage_mask[i];
-                       int length = util_last_bit(outputs[noutput].usage_mask);
+                       outputs[noutput].usage_mask = output_usage_mask;
 
                        for (unsigned j = 0; j < length; j++, out_idx++) {
+                               if (!(output_usage_mask & (1 << j)))
+                                       continue;
+
                                gep_idx[2] = LLVMConstInt(ctx->ac.i32, out_idx, false);
                                tmp = LLVMBuildGEP(builder, vertexptr, gep_idx, 3, "");
                                tmp = LLVMBuildLoad(builder, tmp, "");