/*
* 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 "compiler/glsl_types.h"
#include "compiler/nir/nir_builder.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);
nir_const_value *const_offset = nir_src_as_const_value(*offset);
if (const_offset) {
intrin->const_index[0] += const_offset->u32[0];
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_vs_attrs(nir_block *block, shader_info *nir_info)
{
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) {
/* 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 = intrin->const_index[0];
int slot = _mesa_bitcount_64(nir_info->inputs_read &
BITFIELD64_MASK(attr));
intrin->const_index[0] = 4 * slot;
}
}
return true;
}
static bool
remap_inputs_with_vue_map(nir_block *block, const struct brw_vue_map *vue_map)
{
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) {
int vue_slot = vue_map->varying_to_slot[intrin->const_index[0]];
assert(vue_slot != -1);
intrin->const_index[0] = vue_slot;
}
}
return true;
}
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->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) {
nir_const_value *const_vertex = nir_src_as_const_value(*vertex);
if (const_vertex) {
intrin->const_index[0] += const_vertex->u32[0] *
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,
bool is_scalar,
bool use_legacy_snorm_formula,
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, use_legacy_snorm_formula,
vs_attrib_wa_flags);
if (is_scalar) {
/* Finally, translate VERT_ATTRIB_* values into the actual registers. */
nir_foreach_function(function, nir) {
if (function->impl) {
nir_foreach_block(block, function->impl) {
remap_vs_attrs(block, nir->info);
}
}
}
}
}
void
brw_nir_lower_vue_inputs(nir_shader *nir, bool is_scalar,
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);
if (is_scalar || nir->stage != MESA_SHADER_GEOMETRY) {
/* 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_foreach_block(block, function->impl) {
remap_inputs_with_vue_map(block, vue_map);
}
}
}
}
}
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,
bool is_scalar)
{
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);
}
void
brw_nir_lower_cs_shared(nir_shader *nir)
{
nir_assign_var_locations(&nir->shared, &nir->num_shared,
type_size_scalar_bytes);
nir_lower_io(nir, nir_var_shared, type_size_scalar_bytes, 0);
}
#define OPT(pass, ...) ({ \
bool this_progress = false; \
NIR_PASS(this_progress, nir, pass, ##__VA_ARGS__); \
if (this_progress) \
progress = true; \
this_progress; \
})
#define OPT_V(pass, ...) NIR_PASS_V(nir, pass, ##__VA_ARGS__)
static nir_shader *
nir_optimize(nir_shader *nir, const struct brw_compiler *compiler,
bool is_scalar)
{
nir_variable_mode indirect_mask = 0;
if (compiler->glsl_compiler_options[nir->stage].EmitNoIndirectInput)
indirect_mask |= nir_var_shader_in;
if (compiler->glsl_compiler_options[nir->stage].EmitNoIndirectOutput)
indirect_mask |= nir_var_shader_out;
if (compiler->glsl_compiler_options[nir->stage].EmitNoIndirectTemp)
indirect_mask |= nir_var_local;
bool progress;
do {
progress = false;
OPT_V(nir_lower_vars_to_ssa);
OPT(nir_opt_copy_prop_vars);
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_peephole_select, 0);
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);
if (nir->options->max_unroll_iterations != 0) {
OPT(nir_opt_loop_unroll, indirect_mask);
}
OPT(nir_opt_remove_phis);
OPT(nir_opt_undef);
OPT_V(nir_lower_doubles, nir_lower_drcp |
nir_lower_dsqrt |
nir_lower_drsq |
nir_lower_dtrunc |
nir_lower_dfloor |
nir_lower_dceil |
nir_lower_dfract |
nir_lower_dround_even |
nir_lower_dmod);
OPT_V(nir_lower_double_pack);
} while (progress);
return nir;
}
/* 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 struct gen_device_info *devinfo = compiler->devinfo;
bool progress; /* Written by OPT and OPT_V */
(void)progress;
const bool is_scalar = compiler->scalar_stage[nir->stage];
if (nir->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_txd_cube_map = true,
};
OPT(nir_lower_tex, &tex_options);
OPT(nir_normalize_cubemap_coords);
OPT(nir_lower_global_vars_to_local);
OPT(nir_split_var_copies);
nir = nir_optimize(nir, compiler, is_scalar);
if (is_scalar) {
OPT_V(nir_lower_load_const_to_scalar);
}
/* Lower a bunch of stuff */
OPT_V(nir_lower_var_copies);
OPT_V(nir_lower_clip_cull_distance_arrays);
nir_variable_mode indirect_mask = 0;
if (compiler->glsl_compiler_options[nir->stage].EmitNoIndirectInput)
indirect_mask |= nir_var_shader_in;
if (compiler->glsl_compiler_options[nir->stage].EmitNoIndirectOutput)
indirect_mask |= nir_var_shader_out;
if (compiler->glsl_compiler_options[nir->stage].EmitNoIndirectTemp)
indirect_mask |= nir_var_local;
nir_lower_indirect_derefs(nir, indirect_mask);
/* Get rid of split copies */
nir = nir_optimize(nir, compiler, is_scalar);
OPT(nir_remove_dead_variables, nir_var_local);
return nir;
}
/* 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->stage));
bool progress; /* Written by OPT and OPT_V */
(void)progress;
nir = nir_optimize(nir, compiler, is_scalar);
if (devinfo->gen >= 6) {
/* Try and fuse multiply-adds */
OPT(brw_nir_opt_peephole_ffma);
}
OPT(nir_opt_algebraic_late);
OPT_V(nir_lower_to_source_mods);
OPT(nir_copy_prop);
OPT(nir_opt_dce);
OPT(nir_opt_move_comparisons);
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->stage));
nir_print_shader(nir, stderr);
}
OPT_V(nir_convert_from_ssa, true);
if (!is_scalar) {
OPT_V(nir_move_vec_src_uses_to_dest);
OPT(nir_lower_vec_to_movs);
}
/* 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->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 = { 0 };
/* 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;
if (nir_lower_tex(nir, &tex_options)) {
nir_validate_shader(nir);
nir = nir_optimize(nir, compiler, is_scalar);
}
return nir;
}
enum brw_reg_type
brw_type_for_nir_type(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_float64:
return BRW_REGISTER_TYPE_DF;
case nir_type_int64:
case nir_type_uint64:
/* TODO we should only see these in moves, so for now it's ok, but when
* we add actual 64-bit integer support we should fix this.
*/
return BRW_REGISTER_TYPE_DF;
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_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;
default:
unreachable("bad type");
}
}