radeonsi: only export from GS copy shader for vertex stream 0

When running the copy shader for vertex streams != 0, the SX does not need
any data from us (there is no rasterization for the higher vertex streams,
only streamout).

Reviewed-by: Marek Olšák <marek.olsak@amd.com>

diff --git a/src/gallium/drivers/radeonsi/si_shader.c b/src/gallium/drivers/radeonsi/si_shader.c
index 7c8fad1..daff629 100644 (file)
--- a/src/gallium/drivers/radeonsi/si_shader.c
+++ b/src/gallium/drivers/radeonsi/si_shader.c
@@ -6421,26 +6421,33 @@ si_generate_gs_copy_shader(struct si_screen *sscreen,
                }
        }
 
-       if (gs_selector->so.num_outputs) {
-               for (int stream = 0; stream < 4; stream++) {
-                       struct lp_build_if_state if_ctx_stream;
+       for (int stream = 0; stream < 4; stream++) {
+               struct lp_build_if_state if_ctx_stream;
 
-                       if (!gsinfo->num_stream_output_components[stream])
-                               continue;
+               if (!gsinfo->num_stream_output_components[stream])
+                       continue;
+
+               if (stream > 0 && !gs_selector->so.num_outputs)
+                       continue;
 
-                       LLVMValueRef is_stream =
-                               LLVMBuildICmp(builder, LLVMIntEQ,
-                                             stream_id,
-                                             lp_build_const_int32(gallivm, stream), "");
+               LLVMValueRef is_stream =
+                       LLVMBuildICmp(builder, LLVMIntEQ,
+                                     stream_id,
+                                     lp_build_const_int32(gallivm, stream), "");
 
-                       lp_build_if(&if_ctx_stream, gallivm, is_stream);
+               lp_build_if(&if_ctx_stream, gallivm, is_stream);
+
+               if (gs_selector->so.num_outputs) {
                        si_llvm_emit_streamout(&ctx, outputs,
                                               gsinfo->num_outputs,
                                               stream);
-                       lp_build_endif(&if_ctx_stream);
                }
+
+               if (stream == 0)
+                       si_llvm_export_vs(bld_base, outputs, gsinfo->num_outputs);
+
+               lp_build_endif(&if_ctx_stream);
        }
-       si_llvm_export_vs(bld_base, outputs, gsinfo->num_outputs);
 
        LLVMBuildRetVoid(gallivm->builder);