st/glsl_to_nir: disable io lowering to temps for tess

Lowering these to temps makes a big mess, and results in some
piglit test failures. Also the radeonsi backend (the only backend
to support tess) has support for indirects so there is no need to
lower them anyway.

Fixes the following piglit tests on radeonsi:

tests/spec/arb_tessellation_shader/execution/variable-indexing/tes-input-array-vec3-index-rd.shader_test
tests/spec/arb_tessellation_shader/execution/variable-indexing/tes-input-array-vec4-index-rd.shader_test

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

diff --git a/src/mesa/state_tracker/st_glsl_to_nir.cpp b/src/mesa/state_tracker/st_glsl_to_nir.cpp
index 1c5de3d..bd6d588 100644 (file)
--- a/src/mesa/state_tracker/st_glsl_to_nir.cpp
+++ b/src/mesa/state_tracker/st_glsl_to_nir.cpp
@@ -490,9 +490,12 @@ st_nir_get_mesa_program(struct gl_context *ctx,
    set_st_program(prog, shader_program, nir);
    prog->nir = nir;
 
-   NIR_PASS_V(nir, nir_lower_io_to_temporaries,
-              nir_shader_get_entrypoint(nir),
-              true, true);
+   if (nir->info.stage != MESA_SHADER_TESS_CTRL &&
+       nir->info.stage != MESA_SHADER_TESS_EVAL) {
+      NIR_PASS_V(nir, nir_lower_io_to_temporaries,
+                 nir_shader_get_entrypoint(nir),
+                 true, true);
+   }
    NIR_PASS_V(nir, nir_lower_global_vars_to_local);
    NIR_PASS_V(nir, nir_split_var_copies);
    NIR_PASS_V(nir, nir_lower_var_copies);
@@ -665,7 +668,8 @@ st_finalize_nir(struct st_context *st, struct gl_program *prog,
 
    NIR_PASS_V(nir, nir_split_var_copies);
    NIR_PASS_V(nir, nir_lower_var_copies);
-   if (nir->info.stage != MESA_SHADER_TESS_CTRL)
+   if (nir->info.stage != MESA_SHADER_TESS_CTRL &&
+       nir->info.stage != MESA_SHADER_TESS_EVAL)
       NIR_PASS_V(nir, nir_lower_io_arrays_to_elements_no_indirects);
 
    if (nir->info.stage == MESA_SHADER_VERTEX) {