mesa/src/compiler/nir/nir_lower_passthrough_edgef...

105 lines
3.7 KiB
C

/*
* Copyright © 2015 Red Hat
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include "nir.h"
#include "nir_builder.h"
static void
lower_impl(nir_function_impl *impl)
{
nir_shader *shader = impl->function->shader;
nir_builder b;
nir_variable *in, *out;
nir_ssa_def *def;
nir_builder_init(&b, impl);
b.cursor = nir_before_cf_list(&impl->body);
/* The edge flag is the last input in st/mesa. This code is also called by
* i965 which calls it before any input locations are assigned.
*/
assert(shader->num_inputs == 0 ||
shader->num_inputs == util_bitcount64(shader->info.inputs_read));
/* Lowered IO only uses intrinsics. It doesn't use variables. */
if (shader->info.io_lowered) {
assert(shader->num_outputs ==
util_bitcount64(shader->info.outputs_written));
/* Load an edge flag. */
nir_io_semantics load_sem = {0};
load_sem.location = VERT_ATTRIB_EDGEFLAG;
load_sem.num_slots = 1;
nir_ssa_def *load =
nir_load_input(&b, 1, 32, nir_imm_int(&b, 0),
.base = shader->num_inputs++,
.component = 0,
.dest_type = nir_type_float32,
.io_semantics = load_sem);
/* Store an edge flag. */
nir_io_semantics semantics = {0};
semantics.location = VARYING_SLOT_EDGE;
semantics.num_slots = 1;
nir_store_output(&b, load, nir_imm_int(&b, 0),
.base = shader->num_outputs++,
.component = 0,
.io_semantics = semantics,
.src_type = nir_type_float32,
.write_mask = 0x1);
nir_metadata_preserve(impl, nir_metadata_block_index |
nir_metadata_dominance);
return;
}
in = nir_variable_create(shader, nir_var_shader_in,
glsl_vec4_type(), "edgeflag_in");
in->data.location = VERT_ATTRIB_EDGEFLAG;
in->data.driver_location = shader->num_inputs++;
shader->info.inputs_read |= VERT_BIT_EDGEFLAG;
out = nir_variable_create(shader, nir_var_shader_out,
glsl_vec4_type(), "edgeflag_out");
out->data.location = VARYING_SLOT_EDGE;
shader->info.outputs_written |= VARYING_BIT_EDGE;
def = nir_load_var(&b, in);
nir_store_var(&b, out, def, 0xf);
nir_metadata_preserve(impl, nir_metadata_block_index |
nir_metadata_dominance);
}
void nir_lower_passthrough_edgeflags(nir_shader *shader)
{
assert(shader->info.stage == MESA_SHADER_VERTEX);
shader->info.vs.needs_edge_flag = true;
lower_impl(nir_shader_get_entrypoint(shader));
}