/*
* 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.
*
* Authors:
* Connor Abbott (cwabbott0@gmail.com)
* Jason Ekstrand (jason@jlekstrand.net)
*
*/
/*
* This lowering pass converts references to input/output variables with
* loads/stores to actual input/output intrinsics.
*
* NOTE: This pass really only works for scalar backends at the moment due
* to the way it packes the input/output data.
*/
#include "nir.h"
struct lower_io_state {
void *mem_ctx;
};
static unsigned
type_size(const struct glsl_type *type)
{
unsigned int size, i;
switch (glsl_get_base_type(type)) {
case GLSL_TYPE_UINT:
case GLSL_TYPE_INT:
case GLSL_TYPE_FLOAT:
case GLSL_TYPE_BOOL:
return glsl_get_components(type);
case GLSL_TYPE_ARRAY:
return type_size(glsl_get_array_element(type)) * glsl_get_length(type);
case GLSL_TYPE_STRUCT:
size = 0;
for (i = 0; i < glsl_get_length(type); i++) {
size += type_size(glsl_get_struct_field(type, i));
}
return size;
case GLSL_TYPE_SAMPLER:
return 0;
case GLSL_TYPE_ATOMIC_UINT:
return 0;
case GLSL_TYPE_INTERFACE:
return 0;
case GLSL_TYPE_IMAGE:
return 0;
case GLSL_TYPE_VOID:
case GLSL_TYPE_ERROR:
case GLSL_TYPE_DOUBLE:
unreachable("not reached");
}
return 0;
}
void
nir_assign_var_locations_scalar(struct exec_list *var_list, unsigned *size)
{
unsigned location = 0;
foreach_list_typed(nir_variable, var, node, var_list) {
/*
* UBO's have their own address spaces, so don't count them towards the
* number of global uniforms
*/
if (var->data.mode == nir_var_uniform && var->interface_type != NULL)
continue;
var->data.driver_location = location;
location += type_size(var->type);
}
*size = location;
}
static bool
deref_has_indirect(nir_deref_var *deref)
{
for (nir_deref *tail = deref->deref.child; tail; tail = tail->child) {
if (tail->deref_type == nir_deref_type_array) {
nir_deref_array *arr = nir_deref_as_array(tail);
if (arr->deref_array_type == nir_deref_array_type_indirect)
return true;
}
}
return false;
}
static bool
mark_indirect_uses_block(nir_block *block, void *void_state)
{
struct set *indirect_set = void_state;
nir_foreach_instr(block, instr) {
if (instr->type != nir_instr_type_intrinsic)
continue;
nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
for (unsigned i = 0;
i < nir_intrinsic_infos[intrin->intrinsic].num_variables; i++) {
if (deref_has_indirect(intrin->variables[i]))
_mesa_set_add(indirect_set, intrin->variables[i]->var);
}
}
return true;
}
/* Identical to nir_assign_var_locations_packed except that it assigns
* locations to the variables that are used 100% directly first and then
* assigns locations to variables that are used indirectly.
*/
void
nir_assign_var_locations_scalar_direct_first(nir_shader *shader,
struct exec_list *var_list,
unsigned *direct_size,
unsigned *size)
{
struct set *indirect_set = _mesa_set_create(NULL, _mesa_hash_pointer,
_mesa_key_pointer_equal);
nir_foreach_overload(shader, overload) {
if (overload->impl)
nir_foreach_block(overload->impl, mark_indirect_uses_block,
indirect_set);
}
unsigned location = 0;
foreach_list_typed(nir_variable, var, node, var_list) {
if (var->data.mode == nir_var_uniform && var->interface_type != NULL)
continue;
if (_mesa_set_search(indirect_set, var))
continue;
var->data.driver_location = location;
location += type_size(var->type);
}
*direct_size = location;
foreach_list_typed(nir_variable, var, node, var_list) {
if (var->data.mode == nir_var_uniform && var->interface_type != NULL)
continue;
if (!_mesa_set_search(indirect_set, var))
continue;
var->data.driver_location = location;
location += type_size(var->type);
}
*size = location;
_mesa_set_destroy(indirect_set, NULL);
}
static unsigned
get_io_offset(nir_deref_var *deref, nir_instr *instr, nir_src *indirect,
struct lower_io_state *state)
{
bool found_indirect = false;
unsigned base_offset = 0;
nir_deref *tail = &deref->deref;
while (tail->child != NULL) {
const struct glsl_type *parent_type = tail->type;
tail = tail->child;
if (tail->deref_type == nir_deref_type_array) {
nir_deref_array *deref_array = nir_deref_as_array(tail);
unsigned size = type_size(tail->type);
base_offset += size * deref_array->base_offset;
if (deref_array->deref_array_type == nir_deref_array_type_indirect) {
nir_load_const_instr *load_const =
nir_load_const_instr_create(state->mem_ctx, 1);
load_const->value.u[0] = size;
nir_instr_insert_before(instr, &load_const->instr);
nir_alu_instr *mul = nir_alu_instr_create(state->mem_ctx,
nir_op_imul);
mul->src[0].src.is_ssa = true;
mul->src[0].src.ssa = &load_const->def;
nir_src_copy(&mul->src[1].src, &deref_array->indirect,
state->mem_ctx);
mul->dest.write_mask = 1;
nir_ssa_dest_init(&mul->instr, &mul->dest.dest, 1, NULL);
nir_instr_insert_before(instr, &mul->instr);
if (found_indirect) {
nir_alu_instr *add = nir_alu_instr_create(state->mem_ctx,
nir_op_iadd);
add->src[0].src = *indirect;
add->src[1].src.is_ssa = true;
add->src[1].src.ssa = &mul->dest.dest.ssa;
add->dest.write_mask = 1;
nir_ssa_dest_init(&add->instr, &add->dest.dest, 1, NULL);
nir_instr_insert_before(instr, &add->instr);
indirect->is_ssa = true;
indirect->ssa = &add->dest.dest.ssa;
} else {
indirect->is_ssa = true;
indirect->ssa = &mul->dest.dest.ssa;
found_indirect = true;
}
}
} else if (tail->deref_type == nir_deref_type_struct) {
nir_deref_struct *deref_struct = nir_deref_as_struct(tail);
for (unsigned i = 0; i < deref_struct->index; i++)
base_offset += type_size(glsl_get_struct_field(parent_type, i));
}
}
return base_offset;
}
static bool
nir_lower_io_block(nir_block *block, void *void_state)
{
struct lower_io_state *state = void_state;
nir_foreach_instr_safe(block, instr) {
if (instr->type != nir_instr_type_intrinsic)
continue;
nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr);
switch (intrin->intrinsic) {
case nir_intrinsic_load_var: {
nir_variable_mode mode = intrin->variables[0]->var->data.mode;
if (mode != nir_var_shader_in && mode != nir_var_uniform)
continue;
bool has_indirect = deref_has_indirect(intrin->variables[0]);
/* Figure out the opcode */
nir_intrinsic_op load_op;
switch (mode) {
case nir_var_shader_in:
load_op = has_indirect ? nir_intrinsic_load_input_indirect :
nir_intrinsic_load_input;
break;
case nir_var_uniform:
load_op = has_indirect ? nir_intrinsic_load_uniform_indirect :
nir_intrinsic_load_uniform;
break;
default:
unreachable("Unknown variable mode");
}
nir_intrinsic_instr *load = nir_intrinsic_instr_create(state->mem_ctx,
load_op);
load->num_components = intrin->num_components;
nir_src indirect;
unsigned offset = get_io_offset(intrin->variables[0],
&intrin->instr, &indirect, state);
offset += intrin->variables[0]->var->data.driver_location;
load->const_index[0] = offset;
load->const_index[1] = 1;
if (has_indirect)
load->src[0] = indirect;
if (intrin->dest.is_ssa) {
nir_ssa_dest_init(&load->instr, &load->dest,
intrin->num_components, NULL);
nir_ssa_def_rewrite_uses(&intrin->dest.ssa,
nir_src_for_ssa(&load->dest.ssa),
state->mem_ctx);
} else {
nir_dest_copy(&load->dest, &intrin->dest, state->mem_ctx);
}
nir_instr_insert_before(&intrin->instr, &load->instr);
nir_instr_remove(&intrin->instr);
break;
}
case nir_intrinsic_store_var: {
if (intrin->variables[0]->var->data.mode != nir_var_shader_out)
continue;
bool has_indirect = deref_has_indirect(intrin->variables[0]);
nir_intrinsic_op store_op;
if (has_indirect) {
store_op = nir_intrinsic_store_output_indirect;
} else {
store_op = nir_intrinsic_store_output;
}
nir_intrinsic_instr *store = nir_intrinsic_instr_create(state->mem_ctx,
store_op);
store->num_components = intrin->num_components;
nir_src indirect;
unsigned offset = get_io_offset(intrin->variables[0],
&intrin->instr, &indirect, state);
offset += intrin->variables[0]->var->data.driver_location;
store->const_index[0] = offset;
store->const_index[1] = 1;
nir_src_copy(&store->src[0], &intrin->src[0], state->mem_ctx);
if (has_indirect)
store->src[1] = indirect;
nir_instr_insert_before(&intrin->instr, &store->instr);
nir_instr_remove(&intrin->instr);
break;
}
default:
break;
}
}
return true;
}
static void
nir_lower_io_impl(nir_function_impl *impl)
{
struct lower_io_state state;
state.mem_ctx = ralloc_parent(impl);
nir_foreach_block(impl, nir_lower_io_block, &state);
nir_metadata_preserve(impl, nir_metadata_block_index |
nir_metadata_dominance);
}
void
nir_lower_io(nir_shader *shader)
{
nir_foreach_overload(shader, overload) {
if (overload->impl)
nir_lower_io_impl(overload->impl);
}
}