/*
* Copyright © 2014 Intel Corporation
*
* 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 "brw_nir.h"
#include "brw_shader.h"
#include "dev/gen_debug.h"
#include "compiler/glsl_types.h"
#include "compiler/nir/nir_builder.h"
#include "util/u_math.h"
static bool
is_input(nir_intrinsic_instr *intrin)
{
return intrin->intrinsic == nir_intrinsic_load_input ||
intrin->intrinsic == nir_intrinsic_load_per_vertex_input ||
intrin->intrinsic == nir_intrinsic_load_interpolated_input;
}
static bool
is_output(nir_intrinsic_instr *intrin)
{
return intrin->intrinsic == nir_intrinsic_load_output ||
intrin->intrinsic == nir_intrinsic_load_per_vertex_output ||
intrin->intrinsic == nir_intrinsic_store_output ||
intrin->intrinsic == nir_intrinsic_store_per_vertex_output;
}
/**
* In many cases, we just add the base and offset together, so there's no
* reason to keep them separate. Sometimes, combining them is essential:
* if a shader only accesses part of a compound variable (such as a matrix
* or array), the variable's base may not actually exist in the VUE map.
*
* This pass adds constant offsets to instr->const_index[0], and resets
* the offset source to 0. Non-constant offsets remain unchanged - since
* we don't know what part of a compound variable is accessed, we allocate
* storage for the entire thing.
*/
static bool
add_const_offset_to_base_block(nir_block *block, nir_builder *b,
nir_variable_mode mode)
{
nir_foreach_instr_safe(instr, block) {
if (instr->type != nir_instr_type_intrinsic)
continue;
nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
if ((mode == nir_var_shader_in && is_input(intrin)) ||
(mode == nir_var_shader_out && is_output(intrin))) {
nir_src *offset = nir_get_io_offset_src(intrin);
if (nir_src_is_const(*offset)) {
intrin->const_index[0] += nir_src_as_uint(*offset);
b->cursor = nir_before_instr(&intrin->instr);
nir_instr_rewrite_src(&intrin->instr, offset,
nir_src_for_ssa(nir_imm_int(b, 0)));
}
}
}
return true;
}
static void
add_const_offset_to_base(nir_shader *nir, nir_variable_mode mode)
{
nir_foreach_function(f, nir) {
if (f->impl) {
nir_builder b;
nir_builder_init(&b, f->impl);
nir_foreach_block(block, f->impl) {
add_const_offset_to_base_block(block, &b, mode);
}
}
}
}
static bool
remap_tess_levels(nir_builder *b, nir_intrinsic_instr *intr,
GLenum primitive_mode)
{
const int location = nir_intrinsic_base(intr);
const unsigned component = nir_intrinsic_component(intr);
bool out_of_bounds;
if (location == VARYING_SLOT_TESS_LEVEL_INNER) {
switch (primitive_mode) {
case GL_QUADS:
/* gl_TessLevelInner[0..1] lives at DWords 3-2 (reversed). */
nir_intrinsic_set_base(intr, 0);
nir_intrinsic_set_component(intr, 3 - component);
out_of_bounds = false;
break;
case GL_TRIANGLES:
/* gl_TessLevelInner[0] lives at DWord 4. */
nir_intrinsic_set_base(intr, 1);
out_of_bounds = component > 0;
break;
case GL_ISOLINES:
out_of_bounds = true;
break;
default:
unreachable("Bogus tessellation domain");
}
} else if (location == VARYING_SLOT_TESS_LEVEL_OUTER) {
if (primitive_mode == GL_ISOLINES) {
/* gl_TessLevelOuter[0..1] lives at DWords 6-7 (in order). */
nir_intrinsic_set_base(intr, 1);
nir_intrinsic_set_component(intr, 2 + nir_intrinsic_component(intr));
out_of_bounds = component > 1;
} else {
/* Triangles use DWords 7-5 (reversed); Quads use 7-4 (reversed) */
nir_intrinsic_set_base(intr, 1);
nir_intrinsic_set_component(intr, 3 - nir_intrinsic_component(intr));
out_of_bounds = component == 3 && primitive_mode == GL_TRIANGLES;
}
} else {
return false;
}
if (out_of_bounds) {
if (nir_intrinsic_infos[intr->intrinsic].has_dest) {
b->cursor = nir_before_instr(&intr->instr);
nir_ssa_def *undef = nir_ssa_undef(b, 1, 32);
nir_ssa_def_rewrite_uses(&intr->dest.ssa, nir_src_for_ssa(undef));
}
nir_instr_remove(&intr->instr);
}
return true;
}
static bool
remap_patch_urb_offsets(nir_block *block, nir_builder *b,
const struct brw_vue_map *vue_map,
GLenum tes_primitive_mode)
{
const bool is_passthrough_tcs = b->shader->info.name &&
strcmp(b->shader->info.name, "passthrough") == 0;
nir_foreach_instr_safe(instr, block) {
if (instr->type != nir_instr_type_intrinsic)
continue;
nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
gl_shader_stage stage = b->shader->info.stage;
if ((stage == MESA_SHADER_TESS_CTRL && is_output(intrin)) ||
(stage == MESA_SHADER_TESS_EVAL && is_input(intrin))) {
if (!is_passthrough_tcs &&
remap_tess_levels(b, intrin, tes_primitive_mode))
continue;
int vue_slot = vue_map->varying_to_slot[intrin->const_index[0]];
assert(vue_slot != -1);
intrin->const_index[0] = vue_slot;
nir_src *vertex = nir_get_io_vertex_index_src(intrin);
if (vertex) {
if (nir_src_is_const(*vertex)) {
intrin->const_index[0] += nir_src_as_uint(*vertex) *
vue_map->num_per_vertex_slots;
} else {
b->cursor = nir_before_instr(&intrin->instr);
/* Multiply by the number of per-vertex slots. */
nir_ssa_def *vertex_offset =
nir_imul(b,
nir_ssa_for_src(b, *vertex, 1),
nir_imm_int(b,
vue_map->num_per_vertex_slots));
/* Add it to the existing offset */
nir_src *offset = nir_get_io_offset_src(intrin);
nir_ssa_def *total_offset =
nir_iadd(b, vertex_offset,
nir_ssa_for_src(b, *offset, 1));
nir_instr_rewrite_src(&intrin->instr, offset,
nir_src_for_ssa(total_offset));
}
}
}
}
return true;
}
void
brw_nir_lower_vs_inputs(nir_shader *nir,
const uint8_t *vs_attrib_wa_flags)
{
/* Start with the location of the variable's base. */
foreach_list_typed(nir_variable, var, node, &nir->inputs) {
var->data.driver_location = var->data.location;
}
/* Now use nir_lower_io to walk dereference chains. Attribute arrays are
* loaded as one vec4 or dvec4 per element (or matrix column), depending on
* whether it is a double-precision type or not.
*/
nir_lower_io(nir, nir_var_shader_in, type_size_vec4, 0);
/* This pass needs actual constants */
nir_opt_constant_folding(nir);
add_const_offset_to_base(nir, nir_var_shader_in);
brw_nir_apply_attribute_workarounds(nir, vs_attrib_wa_flags);
/* The last step is to remap VERT_ATTRIB_* to actual registers */
/* Whether or not we have any system generated values. gl_DrawID is not
* included here as it lives in its own vec4.
*/
const bool has_sgvs =
nir->info.system_values_read &
(BITFIELD64_BIT(SYSTEM_VALUE_FIRST_VERTEX) |
BITFIELD64_BIT(SYSTEM_VALUE_BASE_INSTANCE) |
BITFIELD64_BIT(SYSTEM_VALUE_VERTEX_ID_ZERO_BASE) |
BITFIELD64_BIT(SYSTEM_VALUE_INSTANCE_ID));
const unsigned num_inputs = util_bitcount64(nir->info.inputs_read);
nir_foreach_function(function, nir) {
if (!function->impl)
continue;
nir_builder b;
nir_builder_init(&b, function->impl);
nir_foreach_block(block, function->impl) {
nir_foreach_instr_safe(instr, block) {
if (instr->type != nir_instr_type_intrinsic)
continue;
nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
switch (intrin->intrinsic) {
case nir_intrinsic_load_first_vertex:
case nir_intrinsic_load_base_instance:
case nir_intrinsic_load_vertex_id_zero_base:
case nir_intrinsic_load_instance_id:
case nir_intrinsic_load_is_indexed_draw:
case nir_intrinsic_load_draw_id: {
b.cursor = nir_after_instr(&intrin->instr);
/* gl_VertexID and friends are stored by the VF as the last
* vertex element. We convert them to load_input intrinsics at
* the right location.
*/
nir_intrinsic_instr *load =
nir_intrinsic_instr_create(nir, nir_intrinsic_load_input);
load->src[0] = nir_src_for_ssa(nir_imm_int(&b, 0));
nir_intrinsic_set_base(load, num_inputs);
switch (intrin->intrinsic) {
case nir_intrinsic_load_first_vertex:
nir_intrinsic_set_component(load, 0);
break;
case nir_intrinsic_load_base_instance:
nir_intrinsic_set_component(load, 1);
break;
case nir_intrinsic_load_vertex_id_zero_base:
nir_intrinsic_set_component(load, 2);
break;
case nir_intrinsic_load_instance_id:
nir_intrinsic_set_component(load, 3);
break;
case nir_intrinsic_load_draw_id:
case nir_intrinsic_load_is_indexed_draw:
/* gl_DrawID and IsIndexedDraw are stored right after
* gl_VertexID and friends if any of them exist.
*/
nir_intrinsic_set_base(load, num_inputs + has_sgvs);
if (intrin->intrinsic == nir_intrinsic_load_draw_id)
nir_intrinsic_set_component(load, 0);
else
nir_intrinsic_set_component(load, 1);
break;
default:
unreachable("Invalid system value intrinsic");
}
load->num_components = 1;
nir_ssa_dest_init(&load->instr, &load->dest, 1, 32, NULL);
nir_builder_instr_insert(&b, &load->instr);
nir_ssa_def_rewrite_uses(&intrin->dest.ssa,
nir_src_for_ssa(&load->dest.ssa));
nir_instr_remove(&intrin->instr);
break;
}
case nir_intrinsic_load_input: {
/* Attributes come in a contiguous block, ordered by their
* gl_vert_attrib value. That means we can compute the slot
* number for an attribute by masking out the enabled attributes
* before it and counting the bits.
*/
int attr = nir_intrinsic_base(intrin);
int slot = util_bitcount64(nir->info.inputs_read &
BITFIELD64_MASK(attr));
nir_intrinsic_set_base(intrin, slot);
break;
}
default:
break; /* Nothing to do */
}
}
}
}
}
void
brw_nir_lower_vue_inputs(nir_shader *nir,
const struct brw_vue_map *vue_map)
{
foreach_list_typed(nir_variable, var, node, &nir->inputs) {
var->data.driver_location = var->data.location;
}
/* Inputs are stored in vec4 slots, so use type_size_vec4(). */
nir_lower_io(nir, nir_var_shader_in, type_size_vec4, 0);
/* This pass needs actual constants */
nir_opt_constant_folding(nir);
add_const_offset_to_base(nir, nir_var_shader_in);
nir_foreach_function(function, nir) {
if (!function->impl)
continue;
nir_foreach_block(block, function->impl) {
nir_foreach_instr(instr, block) {
if (instr->type != nir_instr_type_intrinsic)
continue;
nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
if (intrin->intrinsic == nir_intrinsic_load_input ||
intrin->intrinsic == nir_intrinsic_load_per_vertex_input) {
/* Offset 0 is the VUE header, which contains
* VARYING_SLOT_LAYER [.y], VARYING_SLOT_VIEWPORT [.z], and
* VARYING_SLOT_PSIZ [.w].
*/
int varying = nir_intrinsic_base(intrin);
int vue_slot;
switch (varying) {
case VARYING_SLOT_PSIZ:
nir_intrinsic_set_base(intrin, 0);
nir_intrinsic_set_component(intrin, 3);
break;
default:
vue_slot = vue_map->varying_to_slot[varying];
assert(vue_slot != -1);
nir_intrinsic_set_base(intrin, vue_slot);
break;
}
}
}
}
}
}
void
brw_nir_lower_tes_inputs(nir_shader *nir, const struct brw_vue_map *vue_map)
{
foreach_list_typed(nir_variable, var, node, &nir->inputs) {
var->data.driver_location = var->data.location;
}
nir_lower_io(nir, nir_var_shader_in, type_size_vec4, 0);
/* This pass needs actual constants */
nir_opt_constant_folding(nir);
add_const_offset_to_base(nir, nir_var_shader_in);
nir_foreach_function(function, nir) {
if (function->impl) {
nir_builder b;
nir_builder_init(&b, function->impl);
nir_foreach_block(block, function->impl) {
remap_patch_urb_offsets(block, &b, vue_map,
nir->info.tess.primitive_mode);
}
}
}
}
void
brw_nir_lower_fs_inputs(nir_shader *nir,
const struct gen_device_info *devinfo,
const struct brw_wm_prog_key *key)
{
foreach_list_typed(nir_variable, var, node, &nir->inputs) {
var->data.driver_location = var->data.location;
/* Apply default interpolation mode.
*
* Everything defaults to smooth except for the legacy GL color
* built-in variables, which might be flat depending on API state.
*/
if (var->data.interpolation == INTERP_MODE_NONE) {
const bool flat = key->flat_shade &&
(var->data.location == VARYING_SLOT_COL0 ||
var->data.location == VARYING_SLOT_COL1);
var->data.interpolation = flat ? INTERP_MODE_FLAT
: INTERP_MODE_SMOOTH;
}
/* On Ironlake and below, there is only one interpolation mode.
* Centroid interpolation doesn't mean anything on this hardware --
* there is no multisampling.
*/
if (devinfo->gen < 6) {
var->data.centroid = false;
var->data.sample = false;
}
}
nir_lower_io_options lower_io_options = 0;
if (key->persample_interp)
lower_io_options |= nir_lower_io_force_sample_interpolation;
nir_lower_io(nir, nir_var_shader_in, type_size_vec4, lower_io_options);
/* This pass needs actual constants */
nir_opt_constant_folding(nir);
add_const_offset_to_base(nir, nir_var_shader_in);
}
void
brw_nir_lower_vue_outputs(nir_shader *nir)
{
nir_foreach_variable(var, &nir->outputs) {
var->data.driver_location = var->data.location;
}
nir_lower_io(nir, nir_var_shader_out, type_size_vec4, 0);
}
void
brw_nir_lower_tcs_outputs(nir_shader *nir, const struct brw_vue_map *vue_map,
GLenum tes_primitive_mode)
{
nir_foreach_variable(var, &nir->outputs) {
var->data.driver_location = var->data.location;
}
nir_lower_io(nir, nir_var_shader_out, type_size_vec4, 0);
/* This pass needs actual constants */
nir_opt_constant_folding(nir);
add_const_offset_to_base(nir, nir_var_shader_out);
nir_foreach_function(function, nir) {
if (function->impl) {
nir_builder b;
nir_builder_init(&b, function->impl);
nir_foreach_block(block, function->impl) {
remap_patch_urb_offsets(block, &b, vue_map, tes_primitive_mode);
}
}
}
}
void
brw_nir_lower_fs_outputs(nir_shader *nir)
{
nir_foreach_variable(var, &nir->outputs) {
var->data.driver_location =
SET_FIELD(var->data.index, BRW_NIR_FRAG_OUTPUT_INDEX) |
SET_FIELD(var->data.location, BRW_NIR_FRAG_OUTPUT_LOCATION);
}
nir_lower_io(nir, nir_var_shader_out, type_size_dvec4, 0);
}
#define OPT(pass, ...) ({ \
bool this_progress = false; \
NIR_PASS(this_progress, nir, pass, ##__VA_ARGS__); \
if (this_progress) \
progress = true; \
this_progress; \
})
static nir_variable_mode
brw_nir_no_indirect_mask(const struct brw_compiler *compiler,
gl_shader_stage stage)
{
nir_variable_mode indirect_mask = 0;
if (compiler->glsl_compiler_options[stage].EmitNoIndirectInput)
indirect_mask |= nir_var_shader_in;
if (compiler->glsl_compiler_options[stage].EmitNoIndirectOutput)
indirect_mask |= nir_var_shader_out;
if (compiler->glsl_compiler_options[stage].EmitNoIndirectTemp)
indirect_mask |= nir_var_function_temp;
return indirect_mask;
}
nir_shader *
brw_nir_optimize(nir_shader *nir, const struct brw_compiler *compiler,
bool is_scalar, bool allow_copies)
{
nir_variable_mode indirect_mask =
brw_nir_no_indirect_mask(compiler, nir->info.stage);
bool progress;
do {
progress = false;
OPT(nir_split_array_vars, nir_var_function_temp);
OPT(nir_shrink_vec_array_vars, nir_var_function_temp);
OPT(nir_opt_deref);
OPT(nir_lower_vars_to_ssa);
if (allow_copies) {
/* Only run this pass in the first call to brw_nir_optimize. Later
* calls assume that we've lowered away any copy_deref instructions
* and we don't want to introduce any more.
*/
OPT(nir_opt_find_array_copies);
}
OPT(nir_opt_copy_prop_vars);
OPT(nir_opt_dead_write_vars);
OPT(nir_opt_combine_stores, nir_var_all);
if (is_scalar) {
OPT(nir_lower_alu_to_scalar);
}
OPT(nir_copy_prop);
if (is_scalar) {
OPT(nir_lower_phis_to_scalar);
}
OPT(nir_copy_prop);
OPT(nir_opt_dce);
OPT(nir_opt_cse);
OPT(nir_opt_combine_stores, nir_var_all);
/* Passing 0 to the peephole select pass causes it to convert
* if-statements that contain only move instructions in the branches
* regardless of the count.
*
* Passing 1 to the peephole select pass causes it to convert
* if-statements that contain at most a single ALU instruction (total)
* in both branches. Before Gen6, some math instructions were
* prohibitively expensive and the results of compare operations need an
* extra resolve step. For these reasons, this pass is more harmful
* than good on those platforms.
*
* For indirect loads of uniforms (push constants), we assume that array
* indices will nearly always be in bounds and the cost of the load is
* low. Therefore there shouldn't be a performance benefit to avoid it.
* However, in vec4 tessellation shaders, these loads operate by
* actually pulling from memory.
*/
const bool is_vec4_tessellation = !is_scalar &&
(nir->info.stage == MESA_SHADER_TESS_CTRL ||
nir->info.stage == MESA_SHADER_TESS_EVAL);
OPT(nir_opt_peephole_select, 0, !is_vec4_tessellation, false);
OPT(nir_opt_peephole_select, 1, !is_vec4_tessellation,
compiler->devinfo->gen >= 6);
OPT(nir_opt_intrinsics);
OPT(nir_opt_idiv_const, 32);
OPT(nir_opt_algebraic);
OPT(nir_opt_constant_folding);
OPT(nir_opt_dead_cf);
if (OPT(nir_opt_trivial_continues)) {
/* If nir_opt_trivial_continues makes progress, then we need to clean
* things up if we want any hope of nir_opt_if or nir_opt_loop_unroll
* to make progress.
*/
OPT(nir_copy_prop);
OPT(nir_opt_dce);
}
OPT(nir_opt_if, false);
if (nir->options->max_unroll_iterations != 0) {
OPT(nir_opt_loop_unroll, indirect_mask);
}
OPT(nir_opt_remove_phis);
OPT(nir_opt_undef);
OPT(nir_lower_pack);
} while (progress);
/* Workaround Gfxbench unused local sampler variable which will trigger an
* assert in the opt_large_constants pass.
*/
OPT(nir_remove_dead_variables, nir_var_function_temp);
return nir;
}
static unsigned
lower_bit_size_callback(const nir_alu_instr *alu, UNUSED void *data)
{
assert(alu->dest.dest.is_ssa);
if (alu->dest.dest.ssa.bit_size >= 32)
return 0;
const struct brw_compiler *compiler = (const struct brw_compiler *) data;
switch (alu->op) {
case nir_op_idiv:
case nir_op_imod:
case nir_op_irem:
case nir_op_udiv:
case nir_op_umod:
case nir_op_fceil:
case nir_op_ffloor:
case nir_op_ffract:
case nir_op_fround_even:
case nir_op_ftrunc:
return 32;
case nir_op_frcp:
case nir_op_frsq:
case nir_op_fsqrt:
case nir_op_fpow:
case nir_op_fexp2:
case nir_op_flog2:
case nir_op_fsin:
case nir_op_fcos:
return compiler->devinfo->gen < 9 ? 32 : 0;
default:
return 0;
}
}
/* Does some simple lowering and runs the standard suite of optimizations
*
* This is intended to be called more-or-less directly after you get the
* shader out of GLSL or some other source. While it is geared towards i965,
* it is not at all generator-specific except for the is_scalar flag. Even
* there, it is safe to call with is_scalar = false for a shader that is
* intended for the FS backend as long as nir_optimize is called again with
* is_scalar = true to scalarize everything prior to code gen.
*/
nir_shader *
brw_preprocess_nir(const struct brw_compiler *compiler, nir_shader *nir,
const nir_shader *softfp64)
{
const struct gen_device_info *devinfo = compiler->devinfo;
UNUSED bool progress; /* Written by OPT */
const bool is_scalar = compiler->scalar_stage[nir->info.stage];
if (is_scalar) {
OPT(nir_lower_alu_to_scalar);
}
if (nir->info.stage == MESA_SHADER_GEOMETRY)
OPT(nir_lower_gs_intrinsics);
/* See also brw_nir_trig_workarounds.py */
if (compiler->precise_trig &&
!(devinfo->gen >= 10 || devinfo->is_kabylake))
OPT(brw_nir_apply_trig_workarounds);
static const nir_lower_tex_options tex_options = {
.lower_txp = ~0,
.lower_txf_offset = true,
.lower_rect_offset = true,
.lower_tex_without_implicit_lod = true,
.lower_txd_cube_map = true,
.lower_txb_shadow_clamp = true,
.lower_txd_shadow_clamp = true,
.lower_txd_offset_clamp = true,
.lower_tg4_offsets = true,
};
OPT(nir_lower_tex, &tex_options);
OPT(nir_normalize_cubemap_coords);
OPT(nir_lower_global_vars_to_local);
OPT(nir_split_var_copies);
OPT(nir_split_struct_vars, nir_var_function_temp);
nir = brw_nir_optimize(nir, compiler, is_scalar, true);
bool lowered_64bit_ops = false;
do {
progress = false;
OPT(nir_lower_int64, nir->options->lower_int64_options);
OPT(nir_lower_doubles, softfp64, nir->options->lower_doubles_options);
/* Necessary to lower add -> sub and div -> mul/rcp */
OPT(nir_opt_algebraic);
lowered_64bit_ops |= progress;
} while (progress);
/* This needs to be run after the first optimization pass but before we
* lower indirect derefs away
*/
if (compiler->supports_shader_constants) {
OPT(nir_opt_large_constants, NULL, 32);
}
OPT(nir_lower_bit_size, lower_bit_size_callback, (void *)compiler);
if (is_scalar) {
OPT(nir_lower_load_const_to_scalar);
}
/* Lower a bunch of stuff */
OPT(nir_lower_var_copies);
OPT(nir_lower_system_values);
const nir_lower_subgroups_options subgroups_options = {
.subgroup_size = BRW_SUBGROUP_SIZE,
.ballot_bit_size = 32,
.lower_to_scalar = true,
.lower_subgroup_masks = true,
.lower_vote_trivial = !is_scalar,
.lower_shuffle = true,
};
OPT(nir_lower_subgroups, &subgroups_options);
OPT(nir_lower_clip_cull_distance_arrays);
nir_variable_mode indirect_mask =
brw_nir_no_indirect_mask(compiler, nir->info.stage);
OPT(nir_lower_indirect_derefs, indirect_mask);
/* Lower array derefs of vectors for SSBO and UBO loads. For both UBOs and
* SSBOs, our back-end is capable of loading an entire vec4 at a time and
* we would like to take advantage of that whenever possible regardless of
* whether or not the app gives us full loads. This should allow the
* optimizer to combine UBO and SSBO load operations and save us some send
* messages.
*/
OPT(nir_lower_array_deref_of_vec,
nir_var_mem_ubo | nir_var_mem_ssbo,
nir_lower_direct_array_deref_of_vec_load);
/* Get rid of split copies */
nir = brw_nir_optimize(nir, compiler, is_scalar, false);
return nir;
}
void
brw_nir_link_shaders(const struct brw_compiler *compiler,
nir_shader **producer, nir_shader **consumer)
{
nir_lower_io_arrays_to_elements(*producer, *consumer);
nir_validate_shader(*producer, "after nir_lower_io_arrays_to_elements");
nir_validate_shader(*consumer, "after nir_lower_io_arrays_to_elements");
const bool p_is_scalar =
compiler->scalar_stage[(*producer)->info.stage];
const bool c_is_scalar =
compiler->scalar_stage[(*consumer)->info.stage];
if (p_is_scalar && c_is_scalar) {
NIR_PASS_V(*producer, nir_lower_io_to_scalar_early, nir_var_shader_out);
NIR_PASS_V(*consumer, nir_lower_io_to_scalar_early, nir_var_shader_in);
*producer = brw_nir_optimize(*producer, compiler, p_is_scalar, false);
*consumer = brw_nir_optimize(*consumer, compiler, c_is_scalar, false);
}
if (nir_link_opt_varyings(*producer, *consumer))
*consumer = brw_nir_optimize(*consumer, compiler, c_is_scalar, false);
NIR_PASS_V(*producer, nir_remove_dead_variables, nir_var_shader_out);
NIR_PASS_V(*consumer, nir_remove_dead_variables, nir_var_shader_in);
if (nir_remove_unused_varyings(*producer, *consumer)) {
NIR_PASS_V(*producer, nir_lower_global_vars_to_local);
NIR_PASS_V(*consumer, nir_lower_global_vars_to_local);
/* The backend might not be able to handle indirects on
* temporaries so we need to lower indirects on any of the
* varyings we have demoted here.
*/
NIR_PASS_V(*producer, nir_lower_indirect_derefs,
brw_nir_no_indirect_mask(compiler, (*producer)->info.stage));
NIR_PASS_V(*consumer, nir_lower_indirect_derefs,
brw_nir_no_indirect_mask(compiler, (*consumer)->info.stage));
*producer = brw_nir_optimize(*producer, compiler, p_is_scalar, false);
*consumer = brw_nir_optimize(*consumer, compiler, c_is_scalar, false);
}
NIR_PASS_V(*producer, nir_lower_io_to_vector, nir_var_shader_out);
NIR_PASS_V(*producer, nir_opt_combine_stores, nir_var_shader_out);
NIR_PASS_V(*consumer, nir_lower_io_to_vector, nir_var_shader_in);
if ((*producer)->info.stage != MESA_SHADER_TESS_CTRL) {
/* Calling lower_io_to_vector creates output variable writes with
* write-masks. On non-TCS outputs, the back-end can't handle it and we
* need to call nir_lower_io_to_temporaries to get rid of them. This,
* in turn, creates temporary variables and extra copy_deref intrinsics
* that we need to clean up.
*/
NIR_PASS_V(*producer, nir_lower_io_to_temporaries,
nir_shader_get_entrypoint(*producer), true, false);
NIR_PASS_V(*producer, nir_lower_global_vars_to_local);
NIR_PASS_V(*producer, nir_split_var_copies);
NIR_PASS_V(*producer, nir_lower_var_copies);
}
}
/* Prepare the given shader for codegen
*
* This function is intended to be called right before going into the actual
* backend and is highly backend-specific. Also, once this function has been
* called on a shader, it will no longer be in SSA form so most optimizations
* will not work.
*/
nir_shader *
brw_postprocess_nir(nir_shader *nir, const struct brw_compiler *compiler,
bool is_scalar)
{
const struct gen_device_info *devinfo = compiler->devinfo;
bool debug_enabled =
(INTEL_DEBUG & intel_debug_flag_for_shader_stage(nir->info.stage));
UNUSED bool progress; /* Written by OPT */
OPT(brw_nir_lower_mem_access_bit_sizes);
OPT(nir_lower_int64, nir->options->lower_int64_options);
do {
progress = false;
OPT(nir_opt_algebraic_before_ffma);
} while (progress);
nir = brw_nir_optimize(nir, compiler, is_scalar, false);
if (devinfo->gen >= 6) {
/* Try and fuse multiply-adds */
OPT(brw_nir_opt_peephole_ffma);
}
if (OPT(nir_opt_comparison_pre)) {
OPT(nir_copy_prop);
OPT(nir_opt_dce);
OPT(nir_opt_cse);
/* Do the select peepehole again. nir_opt_comparison_pre (combined with
* the other optimization passes) will have removed at least one
* instruction from one of the branches of the if-statement, so now it
* might be under the threshold of conversion to bcsel.
*
* See brw_nir_optimize for the explanation of is_vec4_tessellation.
*/
const bool is_vec4_tessellation = !is_scalar &&
(nir->info.stage == MESA_SHADER_TESS_CTRL ||
nir->info.stage == MESA_SHADER_TESS_EVAL);
OPT(nir_opt_peephole_select, 0, is_vec4_tessellation, false);
OPT(nir_opt_peephole_select, 1, is_vec4_tessellation,
compiler->devinfo->gen >= 6);
}
OPT(nir_opt_algebraic_late);
OPT(brw_nir_lower_conversions);
OPT(nir_lower_to_source_mods, nir_lower_all_source_mods);
OPT(nir_copy_prop);
OPT(nir_opt_dce);
OPT(nir_opt_move_comparisons);
OPT(nir_lower_bool_to_int32);
OPT(nir_lower_locals_to_regs);
if (unlikely(debug_enabled)) {
/* Re-index SSA defs so we print more sensible numbers. */
nir_foreach_function(function, nir) {
if (function->impl)
nir_index_ssa_defs(function->impl);
}
fprintf(stderr, "NIR (SSA form) for %s shader:\n",
_mesa_shader_stage_to_string(nir->info.stage));
nir_print_shader(nir, stderr);
}
OPT(nir_convert_from_ssa, true);
if (!is_scalar) {
OPT(nir_move_vec_src_uses_to_dest);
OPT(nir_lower_vec_to_movs);
}
OPT(nir_opt_dce);
/* This is the last pass we run before we start emitting stuff. It
* determines when we need to insert boolean resolves on Gen <= 5. We
* run it last because it stashes data in instr->pass_flags and we don't
* want that to be squashed by other NIR passes.
*/
if (devinfo->gen <= 5)
brw_nir_analyze_boolean_resolves(nir);
nir_sweep(nir);
if (unlikely(debug_enabled)) {
fprintf(stderr, "NIR (final form) for %s shader:\n",
_mesa_shader_stage_to_string(nir->info.stage));
nir_print_shader(nir, stderr);
}
return nir;
}
nir_shader *
brw_nir_apply_sampler_key(nir_shader *nir,
const struct brw_compiler *compiler,
const struct brw_sampler_prog_key_data *key_tex,
bool is_scalar)
{
const struct gen_device_info *devinfo = compiler->devinfo;
nir_lower_tex_options tex_options = {
.lower_txd_clamp_bindless_sampler = true,
.lower_txd_clamp_if_sampler_index_not_lt_16 = true,
};
/* Iron Lake and prior require lowering of all rectangle textures */
if (devinfo->gen < 6)
tex_options.lower_rect = true;
/* Prior to Broadwell, our hardware can't actually do GL_CLAMP */
if (devinfo->gen < 8) {
tex_options.saturate_s = key_tex->gl_clamp_mask[0];
tex_options.saturate_t = key_tex->gl_clamp_mask[1];
tex_options.saturate_r = key_tex->gl_clamp_mask[2];
}
/* Prior to Haswell, we have to fake texture swizzle */
for (unsigned s = 0; s < MAX_SAMPLERS; s++) {
if (key_tex->swizzles[s] == SWIZZLE_NOOP)
continue;
tex_options.swizzle_result |= (1 << s);
for (unsigned c = 0; c < 4; c++)
tex_options.swizzles[s][c] = GET_SWZ(key_tex->swizzles[s], c);
}
/* Prior to Haswell, we have to lower gradients on shadow samplers */
tex_options.lower_txd_shadow = devinfo->gen < 8 && !devinfo->is_haswell;
tex_options.lower_y_uv_external = key_tex->y_uv_image_mask;
tex_options.lower_y_u_v_external = key_tex->y_u_v_image_mask;
tex_options.lower_yx_xuxv_external = key_tex->yx_xuxv_image_mask;
tex_options.lower_xy_uxvx_external = key_tex->xy_uxvx_image_mask;
tex_options.lower_ayuv_external = key_tex->ayuv_image_mask;
tex_options.lower_xyuv_external = key_tex->xyuv_image_mask;
/* Setup array of scaling factors for each texture. */
memcpy(&tex_options.scale_factors, &key_tex->scale_factors,
sizeof(tex_options.scale_factors));
if (nir_lower_tex(nir, &tex_options)) {
nir_validate_shader(nir, "after nir_lower_tex");
nir = brw_nir_optimize(nir, compiler, is_scalar, false);
}
return nir;
}
enum brw_reg_type
brw_type_for_nir_type(const struct gen_device_info *devinfo, nir_alu_type type)
{
switch (type) {
case nir_type_uint:
case nir_type_uint32:
return BRW_REGISTER_TYPE_UD;
case nir_type_bool:
case nir_type_int:
case nir_type_bool32:
case nir_type_int32:
return BRW_REGISTER_TYPE_D;
case nir_type_float:
case nir_type_float32:
return BRW_REGISTER_TYPE_F;
case nir_type_float16:
return BRW_REGISTER_TYPE_HF;
case nir_type_float64:
return BRW_REGISTER_TYPE_DF;
case nir_type_int64:
return devinfo->gen < 8 ? BRW_REGISTER_TYPE_DF : BRW_REGISTER_TYPE_Q;
case nir_type_uint64:
return devinfo->gen < 8 ? BRW_REGISTER_TYPE_DF : BRW_REGISTER_TYPE_UQ;
case nir_type_int16:
return BRW_REGISTER_TYPE_W;
case nir_type_uint16:
return BRW_REGISTER_TYPE_UW;
case nir_type_int8:
return BRW_REGISTER_TYPE_B;
case nir_type_uint8:
return BRW_REGISTER_TYPE_UB;
default:
unreachable("unknown type");
}
return BRW_REGISTER_TYPE_F;
}
/* Returns the glsl_base_type corresponding to a nir_alu_type.
* This is used by both brw_vec4_nir and brw_fs_nir.
*/
enum glsl_base_type
brw_glsl_base_type_for_nir_type(nir_alu_type type)
{
switch (type) {
case nir_type_float:
case nir_type_float32:
return GLSL_TYPE_FLOAT;
case nir_type_float16:
return GLSL_TYPE_FLOAT16;
case nir_type_float64:
return GLSL_TYPE_DOUBLE;
case nir_type_int:
case nir_type_int32:
return GLSL_TYPE_INT;
case nir_type_uint:
case nir_type_uint32:
return GLSL_TYPE_UINT;
case nir_type_int16:
return GLSL_TYPE_INT16;
case nir_type_uint16:
return GLSL_TYPE_UINT16;
default:
unreachable("bad type");
}
}
nir_shader *
brw_nir_create_passthrough_tcs(void *mem_ctx, const struct brw_compiler *compiler,
const nir_shader_compiler_options *options,
const struct brw_tcs_prog_key *key)
{
nir_builder b;
nir_builder_init_simple_shader(&b, mem_ctx, MESA_SHADER_TESS_CTRL,
options);
nir_shader *nir = b.shader;
nir_variable *var;
nir_intrinsic_instr *load;
nir_intrinsic_instr *store;
nir_ssa_def *zero = nir_imm_int(&b, 0);
nir_ssa_def *invoc_id = nir_load_invocation_id(&b);
nir->info.inputs_read = key->outputs_written &
~(VARYING_BIT_TESS_LEVEL_INNER | VARYING_BIT_TESS_LEVEL_OUTER);
nir->info.outputs_written = key->outputs_written;
nir->info.tess.tcs_vertices_out = key->input_vertices;
nir->info.name = ralloc_strdup(nir, "passthrough");
nir->num_uniforms = 8 * sizeof(uint32_t);
var = nir_variable_create(nir, nir_var_uniform, glsl_vec4_type(), "hdr_0");
var->data.location = 0;
var = nir_variable_create(nir, nir_var_uniform, glsl_vec4_type(), "hdr_1");
var->data.location = 1;
/* Write the patch URB header. */
for (int i = 0; i <= 1; i++) {
load = nir_intrinsic_instr_create(nir, nir_intrinsic_load_uniform);
load->num_components = 4;
load->src[0] = nir_src_for_ssa(zero);
nir_ssa_dest_init(&load->instr, &load->dest, 4, 32, NULL);
nir_intrinsic_set_base(load, i * 4 * sizeof(uint32_t));
nir_builder_instr_insert(&b, &load->instr);
store = nir_intrinsic_instr_create(nir, nir_intrinsic_store_output);
store->num_components = 4;
store->src[0] = nir_src_for_ssa(&load->dest.ssa);
store->src[1] = nir_src_for_ssa(zero);
nir_intrinsic_set_base(store, VARYING_SLOT_TESS_LEVEL_INNER - i);
nir_intrinsic_set_write_mask(store, WRITEMASK_XYZW);
nir_builder_instr_insert(&b, &store->instr);
}
/* Copy inputs to outputs. */
uint64_t varyings = nir->info.inputs_read;
while (varyings != 0) {
const int varying = ffsll(varyings) - 1;
load = nir_intrinsic_instr_create(nir,
nir_intrinsic_load_per_vertex_input);
load->num_components = 4;
load->src[0] = nir_src_for_ssa(invoc_id);
load->src[1] = nir_src_for_ssa(zero);
nir_ssa_dest_init(&load->instr, &load->dest, 4, 32, NULL);
nir_intrinsic_set_base(load, varying);
nir_builder_instr_insert(&b, &load->instr);
store = nir_intrinsic_instr_create(nir,
nir_intrinsic_store_per_vertex_output);
store->num_components = 4;
store->src[0] = nir_src_for_ssa(&load->dest.ssa);
store->src[1] = nir_src_for_ssa(invoc_id);
store->src[2] = nir_src_for_ssa(zero);
nir_intrinsic_set_base(store, varying);
nir_intrinsic_set_write_mask(store, WRITEMASK_XYZW);
nir_builder_instr_insert(&b, &store->instr);
varyings &= ~BITFIELD64_BIT(varying);
}
nir_validate_shader(nir, "in brw_nir_create_passthrough_tcs");
nir = brw_preprocess_nir(compiler, nir, NULL);
return nir;
}