/*
* Copyright © 2015 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 "main/mtypes.h"
#include "nir.h"
static void
set_io_mask(nir_shader *shader, nir_variable *var, int offset, int len,
bool is_output_read)
{
for (int i = 0; i < len; i++) {
assert(var->data.location != -1);
int idx = var->data.location + offset + i;
bool is_patch_generic = var->data.patch &&
idx != VARYING_SLOT_TESS_LEVEL_INNER &&
idx != VARYING_SLOT_TESS_LEVEL_OUTER &&
idx != VARYING_SLOT_BOUNDING_BOX0 &&
idx != VARYING_SLOT_BOUNDING_BOX1;
uint64_t bitfield;
if (is_patch_generic) {
assert(idx >= VARYING_SLOT_PATCH0 && idx < VARYING_SLOT_TESS_MAX);
bitfield = BITFIELD64_BIT(idx - VARYING_SLOT_PATCH0);
}
else {
assert(idx < VARYING_SLOT_MAX);
bitfield = BITFIELD64_BIT(idx);
}
if (var->data.mode == nir_var_shader_in) {
if (is_patch_generic)
shader->info.patch_inputs_read |= bitfield;
else
shader->info.inputs_read |= bitfield;
if (shader->info.stage == MESA_SHADER_FRAGMENT) {
shader->info.fs.uses_sample_qualifier |= var->data.sample;
}
} else {
assert(var->data.mode == nir_var_shader_out);
if (is_output_read) {
if (is_patch_generic) {
shader->info.patch_outputs_read |= bitfield;
} else {
shader->info.outputs_read |= bitfield;
}
} else {
if (is_patch_generic) {
shader->info.patch_outputs_written |= bitfield;
} else if (!var->data.read_only) {
shader->info.outputs_written |= bitfield;
}
}
if (var->data.fb_fetch_output)
shader->info.outputs_read |= bitfield;
}
}
}
/**
* Mark an entire variable as used. Caller must ensure that the variable
* represents a shader input or output.
*/
static void
mark_whole_variable(nir_shader *shader, nir_variable *var, bool is_output_read)
{
const struct glsl_type *type = var->type;
if (nir_is_per_vertex_io(var, shader->info.stage)) {
assert(glsl_type_is_array(type));
type = glsl_get_array_element(type);
}
const unsigned slots =
var->data.compact ? DIV_ROUND_UP(glsl_get_length(type), 4)
: glsl_count_attribute_slots(type, false);
set_io_mask(shader, var, 0, slots, is_output_read);
}
static unsigned
get_io_offset(nir_deref_var *deref)
{
unsigned offset = 0;
nir_deref *tail = &deref->deref;
while (tail->child != NULL) {
tail = tail->child;
if (tail->deref_type == nir_deref_type_array) {
nir_deref_array *deref_array = nir_deref_as_array(tail);
if (deref_array->deref_array_type == nir_deref_array_type_indirect) {
return -1;
}
offset += glsl_count_attribute_slots(tail->type, false) *
deref_array->base_offset;
}
/* TODO: we can get the offset for structs here see nir_lower_io() */
}
return offset;
}
/**
* Try to mark a portion of the given varying as used. Caller must ensure
* that the variable represents a shader input or output.
*
* If the index can't be interpreted as a constant, or some other problem
* occurs, then nothing will be marked and false will be returned.
*/
static bool
try_mask_partial_io(nir_shader *shader, nir_deref_var *deref, bool is_output_read)
{
nir_variable *var = deref->var;
const struct glsl_type *type = var->type;
if (nir_is_per_vertex_io(var, shader->info.stage)) {
assert(glsl_type_is_array(type));
type = glsl_get_array_element(type);
}
/* The code below only handles:
*
* - Indexing into matrices
* - Indexing into arrays of (arrays, matrices, vectors, or scalars)
*
* For now, we just give up if we see varying structs and arrays of structs
* here marking the entire variable as used.
*/
if (!(glsl_type_is_matrix(type) ||
(glsl_type_is_array(type) && !var->data.compact &&
(glsl_type_is_numeric(glsl_without_array(type)) ||
glsl_type_is_boolean(glsl_without_array(type)))))) {
/* If we don't know how to handle this case, give up and let the
* caller mark the whole variable as used.
*/
return false;
}
unsigned offset = get_io_offset(deref);
if (offset == -1)
return false;
unsigned num_elems;
unsigned elem_width = 1;
unsigned mat_cols = 1;
if (glsl_type_is_array(type)) {
num_elems = glsl_get_aoa_size(type);
if (glsl_type_is_matrix(glsl_without_array(type)))
mat_cols = glsl_get_matrix_columns(glsl_without_array(type));
} else {
num_elems = glsl_get_matrix_columns(type);
}
/* double element width for double types that takes two slots */
if (glsl_type_is_dual_slot(glsl_without_array(type))) {
elem_width *= 2;
}
if (offset >= num_elems * elem_width * mat_cols) {
/* Constant index outside the bounds of the matrix/array. This could
* arise as a result of constant folding of a legal GLSL program.
*
* Even though the spec says that indexing outside the bounds of a
* matrix/array results in undefined behaviour, we don't want to pass
* out-of-range values to set_io_mask() (since this could result in
* slots that don't exist being marked as used), so just let the caller
* mark the whole variable as used.
*/
return false;
}
set_io_mask(shader, var, offset, elem_width, is_output_read);
return true;
}
static void
gather_intrinsic_info(nir_intrinsic_instr *instr, nir_shader *shader)
{
switch (instr->intrinsic) {
case nir_intrinsic_discard:
case nir_intrinsic_discard_if:
assert(shader->info.stage == MESA_SHADER_FRAGMENT);
shader->info.fs.uses_discard = true;
break;
case nir_intrinsic_interp_var_at_centroid:
case nir_intrinsic_interp_var_at_sample:
case nir_intrinsic_interp_var_at_offset:
case nir_intrinsic_load_var:
case nir_intrinsic_store_var: {
nir_variable *var = instr->variables[0]->var;
if (var->data.mode == nir_var_shader_in ||
var->data.mode == nir_var_shader_out) {
bool is_output_read = false;
if (var->data.mode == nir_var_shader_out &&
instr->intrinsic == nir_intrinsic_load_var)
is_output_read = true;
if (!try_mask_partial_io(shader, instr->variables[0], is_output_read))
mark_whole_variable(shader, var, is_output_read);
/* We need to track which input_reads bits correspond to a
* dvec3/dvec4 input attribute */
if (shader->info.stage == MESA_SHADER_VERTEX &&
var->data.mode == nir_var_shader_in &&
glsl_type_is_dual_slot(glsl_without_array(var->type))) {
for (uint i = 0; i < glsl_count_attribute_slots(var->type, false); i++) {
int idx = var->data.location + i;
shader->info.double_inputs_read |= BITFIELD64_BIT(idx);
}
}
}
break;
}
case nir_intrinsic_load_draw_id:
case nir_intrinsic_load_frag_coord:
case nir_intrinsic_load_front_face:
case nir_intrinsic_load_vertex_id:
case nir_intrinsic_load_vertex_id_zero_base:
case nir_intrinsic_load_base_vertex:
case nir_intrinsic_load_base_instance:
case nir_intrinsic_load_instance_id:
case nir_intrinsic_load_sample_id:
case nir_intrinsic_load_sample_pos:
case nir_intrinsic_load_sample_mask_in:
case nir_intrinsic_load_primitive_id:
case nir_intrinsic_load_invocation_id:
case nir_intrinsic_load_local_invocation_id:
case nir_intrinsic_load_local_invocation_index:
case nir_intrinsic_load_work_group_id:
case nir_intrinsic_load_num_work_groups:
case nir_intrinsic_load_tess_coord:
case nir_intrinsic_load_tess_level_outer:
case nir_intrinsic_load_tess_level_inner:
case nir_intrinsic_load_patch_vertices_in:
shader->info.system_values_read |=
(1ull << nir_system_value_from_intrinsic(instr->intrinsic));
break;
case nir_intrinsic_end_primitive:
case nir_intrinsic_end_primitive_with_counter:
assert(shader->info.stage == MESA_SHADER_GEOMETRY);
shader->info.gs.uses_end_primitive = 1;
break;
default:
break;
}
}
static void
gather_tex_info(nir_tex_instr *instr, nir_shader *shader)
{
switch (instr->op) {
case nir_texop_tg4:
shader->info.uses_texture_gather = true;
break;
case nir_texop_txf:
case nir_texop_txf_ms:
case nir_texop_txf_ms_mcs:
shader->info.textures_used_by_txf |=
((1 << MAX2(instr->texture_array_size, 1)) - 1) <<
instr->texture_index;
break;
default:
break;
}
}
static void
gather_alu_info(nir_alu_instr *instr, nir_shader *shader)
{
switch (instr->op) {
case nir_op_fddx:
case nir_op_fddy:
shader->info.uses_fddx_fddy = true;
break;
default:
break;
}
}
static void
gather_info_block(nir_block *block, nir_shader *shader)
{
nir_foreach_instr(instr, block) {
switch (instr->type) {
case nir_instr_type_alu:
gather_alu_info(nir_instr_as_alu(instr), shader);
break;
case nir_instr_type_intrinsic:
gather_intrinsic_info(nir_instr_as_intrinsic(instr), shader);
break;
case nir_instr_type_tex:
gather_tex_info(nir_instr_as_tex(instr), shader);
break;
case nir_instr_type_call:
assert(!"nir_shader_gather_info only works if functions are inlined");
break;
default:
break;
}
}
}
void
nir_shader_gather_info(nir_shader *shader, nir_function_impl *entrypoint)
{
shader->info.num_textures = 0;
shader->info.num_images = 0;
nir_foreach_variable(var, &shader->uniforms) {
const struct glsl_type *type = var->type;
unsigned count = 1;
if (glsl_type_is_array(type)) {
count = glsl_get_aoa_size(type);
type = glsl_without_array(type);
}
if (glsl_type_is_image(type)) {
shader->info.num_images += count;
} else if (glsl_type_is_sampler(type)) {
shader->info.num_textures += count;
}
}
shader->info.inputs_read = 0;
shader->info.outputs_written = 0;
shader->info.outputs_read = 0;
shader->info.patch_outputs_read = 0;
shader->info.double_inputs_read = 0;
shader->info.patch_inputs_read = 0;
shader->info.patch_outputs_written = 0;
shader->info.system_values_read = 0;
if (shader->info.stage == MESA_SHADER_FRAGMENT) {
shader->info.fs.uses_sample_qualifier = false;
}
nir_foreach_block(block, entrypoint) {
gather_info_block(block, shader);
}
}