1 /*
2  * Copyright © 2015 Red Hat
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the next
12  * paragraph) shall be included in all copies or substantial portions of the
13  * Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
21  * SOFTWARE.
22  */
23 
24 #include "nir.h"
25 #include "nir_builder.h"
26 
27 static void
lower_impl(nir_function_impl * impl)28 lower_impl(nir_function_impl *impl)
29 {
30    nir_shader *shader = impl->function->shader;
31    nir_builder b;
32    nir_variable *in, *out;
33    nir_ssa_def *def;
34 
35    nir_builder_init(&b, impl);
36    b.cursor = nir_before_cf_list(&impl->body);
37 
38    in  = nir_variable_create(shader, nir_var_shader_in,
39                              glsl_vec4_type(), "edgeflag_in");
40    in->data.location = VERT_ATTRIB_EDGEFLAG;
41 
42    out = nir_variable_create(shader, nir_var_shader_out,
43                              glsl_vec4_type(), "edgeflag_out");
44    out->data.location = VARYING_SLOT_EDGE;
45 
46    def = nir_load_var(&b, in);
47    nir_store_var(&b, out, def, 0xf);
48 
49    nir_metadata_preserve(impl, nir_metadata_block_index |
50                                nir_metadata_dominance);
51 }
52 
nir_lower_passthrough_edgeflags(nir_shader * shader)53 void nir_lower_passthrough_edgeflags(nir_shader *shader)
54 {
55    lower_impl(nir_shader_get_entrypoint(shader));
56 }
57