mesa/src/freedreno/ir3/ir3_nir_lower_load_barycent...

107 lines
3.7 KiB
C

/*
* Copyright © 2019 Google, Inc.
*
* 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 "compiler/nir/nir_builder.h"
#include "ir3_nir.h"
/**
* This pass lowers load_barycentric_at_offset to dsx.3d/dsy.3d and alu
* instructions.
*/
static nir_ssa_def *
load(nir_builder *b, unsigned ncomp, nir_intrinsic_op op)
{
nir_intrinsic_instr *load_size = nir_intrinsic_instr_create(b->shader, op);
nir_ssa_dest_init(&load_size->instr, &load_size->dest, ncomp, 32, NULL);
nir_builder_instr_insert(b, &load_size->instr);
return &load_size->dest.ssa;
}
static nir_ssa_def *
ir3_nir_lower_load_barycentric_at_offset_instr(nir_builder *b, nir_instr *instr,
void *data)
{
nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr);
enum glsl_interp_mode interp_mode = nir_intrinsic_interp_mode(intr);
#define chan(var, c) nir_channel(b, var, c)
nir_ssa_def *off = intr->src[0].ssa;
/* note: at_offset is defined to be relative to the center of the pixel */
nir_ssa_def *ij = nir_load_barycentric_pixel(b, 32, .interp_mode = interp_mode);
nir_ssa_def *s = load(b, 1, nir_intrinsic_load_persp_center_rhw_ir3);
s = nir_frcp(b, s);
/* scaled ij with s as 3rd component: */
nir_ssa_def *sij =
nir_vec3(b, nir_fmul(b, chan(ij, 0), s), nir_fmul(b, chan(ij, 1), s), s);
nir_ssa_def *foo = nir_fddx(b, sij);
nir_ssa_def *bar = nir_fddy(b, sij);
if (b->shader->info.stage == MESA_SHADER_FRAGMENT)
b->shader->info.fs.needs_quad_helper_invocations = true;
nir_ssa_def *x, *y, *z, *i, *j;
x = nir_ffma(b, chan(off, 0), chan(foo, 0), chan(sij, 0));
y = nir_ffma(b, chan(off, 0), chan(foo, 1), chan(sij, 1));
z = nir_ffma(b, chan(off, 0), chan(foo, 2), chan(sij, 2));
x = nir_ffma(b, chan(off, 1), chan(bar, 0), x);
y = nir_ffma(b, chan(off, 1), chan(bar, 1), y);
z = nir_ffma(b, chan(off, 1), chan(bar, 2), z);
/* convert back into primitive space: */
z = nir_frcp(b, z);
i = nir_fmul(b, z, x);
j = nir_fmul(b, z, y);
ij = nir_vec2(b, i, j);
return ij;
}
static bool
ir3_nir_lower_load_barycentric_at_offset_filter(const nir_instr *instr,
const void *data)
{
return (instr->type == nir_instr_type_intrinsic &&
nir_instr_as_intrinsic(instr)->intrinsic ==
nir_intrinsic_load_barycentric_at_offset);
}
bool
ir3_nir_lower_load_barycentric_at_offset(nir_shader *shader)
{
assert(shader->info.stage == MESA_SHADER_FRAGMENT);
return nir_shader_lower_instructions(
shader, ir3_nir_lower_load_barycentric_at_offset_filter,
ir3_nir_lower_load_barycentric_at_offset_instr, NULL);
}