[Mesa-dev] [PATCH 1/8] nir: add varying array splitting pass
Nicolai Hähnle
nhaehnle at gmail.com
Wed Nov 29 10:47:35 UTC 2017
On 21.11.2017 04:28, Timothy Arceri wrote:
> V2: fix matrix support, non-array matrices were being skipped in v1
> ---
> src/compiler/Makefile.sources | 1 +
> src/compiler/nir/meson.build | 1 +
> src/compiler/nir/nir.h | 1 +
> src/compiler/nir/nir_lower_io_arrays_to_elements.c | 373 +++++++++++++++++++++
> 4 files changed, 376 insertions(+)
> create mode 100644 src/compiler/nir/nir_lower_io_arrays_to_elements.c
>
> diff --git a/src/compiler/Makefile.sources b/src/compiler/Makefile.sources
> index 2ab8e163a2..c5094b7f19 100644
> --- a/src/compiler/Makefile.sources
> +++ b/src/compiler/Makefile.sources
> @@ -219,20 +219,21 @@ NIR_FILES = \
> nir/nir_lower_double_ops.c \
> nir/nir_lower_drawpixels.c \
> nir/nir_lower_global_vars_to_local.c \
> nir/nir_lower_gs_intrinsics.c \
> nir/nir_lower_load_const_to_scalar.c \
> nir/nir_lower_locals_to_regs.c \
> nir/nir_lower_idiv.c \
> nir/nir_lower_indirect_derefs.c \
> nir/nir_lower_int64.c \
> nir/nir_lower_io.c \
> + nir/nir_lower_io_arrays_to_elements.c \
> nir/nir_lower_io_to_temporaries.c \
> nir/nir_lower_io_to_scalar.c \
> nir/nir_lower_io_types.c \
> nir/nir_lower_passthrough_edgeflags.c \
> nir/nir_lower_patch_vertices.c \
> nir/nir_lower_phis_to_scalar.c \
> nir/nir_lower_regs_to_ssa.c \
> nir/nir_lower_returns.c \
> nir/nir_lower_samplers.c \
> nir/nir_lower_samplers_as_deref.c \
> diff --git a/src/compiler/nir/meson.build b/src/compiler/nir/meson.build
> index e5c8326aa0..b61a07773d 100644
> --- a/src/compiler/nir/meson.build
> +++ b/src/compiler/nir/meson.build
> @@ -107,20 +107,21 @@ files_libnir = files(
> 'nir_lower_double_ops.c',
> 'nir_lower_drawpixels.c',
> 'nir_lower_global_vars_to_local.c',
> 'nir_lower_gs_intrinsics.c',
> 'nir_lower_load_const_to_scalar.c',
> 'nir_lower_locals_to_regs.c',
> 'nir_lower_idiv.c',
> 'nir_lower_indirect_derefs.c',
> 'nir_lower_int64.c',
> 'nir_lower_io.c',
> + 'nir_lower_io_arrays_to_elements.c',
> 'nir_lower_io_to_temporaries.c',
> 'nir_lower_io_to_scalar.c',
> 'nir_lower_io_types.c',
> 'nir_lower_passthrough_edgeflags.c',
> 'nir_lower_patch_vertices.c',
> 'nir_lower_phis_to_scalar.c',
> 'nir_lower_regs_to_ssa.c',
> 'nir_lower_returns.c',
> 'nir_lower_samplers.c',
> 'nir_lower_samplers_as_deref.c',
> diff --git a/src/compiler/nir/nir.h b/src/compiler/nir/nir.h
> index f46f614711..c62af4afb9 100644
> --- a/src/compiler/nir/nir.h
> +++ b/src/compiler/nir/nir.h
> @@ -2475,20 +2475,21 @@ bool nir_lower_constant_initializers(nir_shader *shader,
> nir_variable_mode modes);
>
> bool nir_move_vec_src_uses_to_dest(nir_shader *shader);
> bool nir_lower_vec_to_movs(nir_shader *shader);
> void nir_lower_alpha_test(nir_shader *shader, enum compare_func func,
> bool alpha_to_one);
> bool nir_lower_alu_to_scalar(nir_shader *shader);
> bool nir_lower_load_const_to_scalar(nir_shader *shader);
> bool nir_lower_read_invocation_to_scalar(nir_shader *shader);
> bool nir_lower_phis_to_scalar(nir_shader *shader);
> +void nir_lower_io_arrays_to_elements(nir_shader *producer, nir_shader *consumer);
> void nir_lower_io_to_scalar(nir_shader *shader, nir_variable_mode mask);
> void nir_lower_io_to_scalar_early(nir_shader *shader, nir_variable_mode mask);
>
> bool nir_lower_samplers(nir_shader *shader,
> const struct gl_shader_program *shader_program);
> bool nir_lower_samplers_as_deref(nir_shader *shader,
> const struct gl_shader_program *shader_program);
>
> typedef struct nir_lower_subgroups_options {
> uint8_t subgroup_size;
> diff --git a/src/compiler/nir/nir_lower_io_arrays_to_elements.c b/src/compiler/nir/nir_lower_io_arrays_to_elements.c
> new file mode 100644
> index 0000000000..c41f300edb
> --- /dev/null
> +++ b/src/compiler/nir/nir_lower_io_arrays_to_elements.c
> @@ -0,0 +1,373 @@
> +/*
> + * Copyright © 2017 Timothy Arceri
> + *
> + * 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 "nir.h"
> +#include "nir_builder.h"
> +
> +/** @file nir_lower_io_arrays_to_elements.c
> + *
> + * Split arrays/matrices with direct indexing into individual elements. This
> + * will allow optimisation passes to better clean up unused elements.
> + *
> + */
> +
> +static unsigned
> +get_io_offset(nir_builder *b, nir_deref_var *deref, nir_variable *var,
> + unsigned *element_index)
> +{
> + nir_deref *tail = &deref->deref;
> +
> + /* For per-vertex input arrays (i.e. geometry shader inputs), skip the
> + * outermost array index. Process the rest normally.
> + */
> + if (nir_is_per_vertex_io(var, b->shader->info.stage)) {
> + tail = tail->child;
> + }
> +
> + unsigned offset = 0;
> + 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);
> + assert(deref_array->deref_array_type != nir_deref_array_type_indirect);
> +
> + unsigned size = glsl_count_attribute_slots(tail->type, false);
> + offset += size * deref_array->base_offset;
> +
> + unsigned num_elements = glsl_type_is_array(tail->type) ?
> + glsl_get_aoa_size(tail->type) : 1;
> +
> + num_elements *= glsl_type_is_matrix(glsl_without_array(tail->type)) ?
> + glsl_get_matrix_columns(glsl_without_array(tail->type)) : 1;
> +
> + *element_index += num_elements * deref_array->base_offset;
> + } else if (tail->deref_type == nir_deref_type_struct) {
> + /* TODO: we could also add struct splitting support to this pass */
> + break;
Maybe make this an assert to emphasize the point?
> + }
> + }
> +
> + return offset;
> +}
> +
> +static nir_variable **
> +get_array_elements(struct hash_table *ht, nir_variable *var,
> + gl_shader_stage stage)
> +{
> + nir_variable **elements;
> + struct hash_entry *entry = _mesa_hash_table_search(ht, var);
> + if (!entry) {
> + const struct glsl_type *type = var->type;
> + if (nir_is_per_vertex_io(var, stage)) {
> + assert(glsl_type_is_array(type));
> + type = glsl_get_array_element(type);
> + }
> +
> + unsigned num_elements = glsl_type_is_array(type) ?
> + glsl_get_aoa_size(type) : 1;
> +
> + num_elements *= glsl_type_is_matrix(glsl_without_array(type)) ?
> + glsl_get_matrix_columns(glsl_without_array(type)) : 1;
> +
> + elements = (nir_variable **) calloc(num_elements, sizeof(nir_variable *));
> + _mesa_hash_table_insert(ht, var, elements);
> + } else {
> + elements = (nir_variable **) entry->data;
> + }
> +
> + return elements;
> +}
> +
> +static void
> +create_array_deref(nir_intrinsic_instr *arr_intr,
> + nir_intrinsic_instr *element_intr)
> +{
> + assert(arr_intr->variables[0]->deref.child);
> +
> + nir_deref *parent = &element_intr->variables[0]->deref;
> + nir_deref_array *darr =
> + nir_deref_as_array(arr_intr->variables[0]->deref.child);
> + nir_deref_array *ndarr = nir_deref_array_create(parent);
> +
> + ndarr->deref.type = glsl_get_array_element(parent->type);
> + ndarr->deref_array_type = darr->deref_array_type;
> + ndarr->base_offset = darr->base_offset;
> +
> + if (ndarr->deref_array_type == nir_deref_array_type_indirect)
> + nir_src_copy(&ndarr->indirect, &darr->indirect, parent);
> +
> + element_intr->variables[0]->deref.child = &ndarr->deref;
> +}
> +
> +static void
> +lower_array(nir_builder *b, nir_intrinsic_instr *intr, nir_variable *var,
> + struct hash_table *varyings)
> +{
> + b->cursor = nir_before_instr(&intr->instr);
> +
> + nir_variable **elements =
> + get_array_elements(varyings, var, b->shader->info.stage);
> +
> + unsigned elements_index = 0;
> + unsigned io_offset = get_io_offset(b, intr->variables[0], var,
> + &elements_index);
> +
> + nir_variable *element = elements[elements_index];
> + if (!element) {
> + element = nir_variable_clone(var, b->shader);
> + element->data.location = var->data.location + io_offset;
> +
> + const struct glsl_type *type = glsl_without_array(element->type);
> +
> + /* This pass also splits matrices so we need give them a new type. */
> + if (glsl_type_is_matrix(type)) {
> + type = glsl_vector_type(glsl_get_base_type(type),
> + glsl_get_vector_elements(type));
> + }
> +
> + if (nir_is_per_vertex_io(var, b->shader->info.stage)) {
> + type = glsl_get_array_instance(type, glsl_get_length(element->type));
> + }
> +
> + element->type = type;
> + elements[elements_index] = element;
> +
> + nir_shader_add_variable(b->shader, element);
> + }
> +
> + nir_intrinsic_instr *element_intr =
> + nir_intrinsic_instr_create(b->shader, intr->intrinsic);
> + element_intr->num_components = intr->num_components;
> + element_intr->variables[0] = nir_deref_var_create(element_intr, element);
> +
> + if (var->data.mode == nir_var_shader_in) {
I believe this needs to be keyed off the intrinsic type rather than the
variable mode, since at least TCS output variables can also be read from.
> + nir_ssa_dest_init(&element_intr->instr, &element_intr->dest,
> + intr->num_components, intr->dest.ssa.bit_size, NULL);
> +
> + if (intr->intrinsic == nir_intrinsic_interp_var_at_offset ||
> + intr->intrinsic == nir_intrinsic_interp_var_at_sample)
> + nir_src_copy(element_intr->src, intr->src, &element_intr->instr);
&element_int->src[0], &intr->src[0] for clarity, I think.
> +
> + nir_ssa_def_rewrite_uses(&intr->dest.ssa,
> + nir_src_for_ssa(&element_intr->dest.ssa));
> + } else {
> + nir_intrinsic_set_write_mask(element_intr, nir_intrinsic_write_mask(intr));
> + element_intr->src[0] = intr->src[0];
I'm still not 100% up on my NIR, but doesn't this also need to be a
nir_src_copy? I think it makes a difference if there's an indirect
access involved.
> + }
> +
> + if (nir_is_per_vertex_io(var, b->shader->info.stage)) {
> + create_array_deref(intr, element_intr);
> + }
> +
> + nir_builder_instr_insert(b, &element_intr->instr);
> +
> + /* Remove the old load intrinsic */
> + nir_instr_remove(&intr->instr);
> +}
> +
> +static bool
> +deref_has_indirect(nir_builder *b, nir_variable *var, nir_deref_var *deref)
> +{
> + nir_deref *tail = &deref->deref;
> +
> + if (nir_is_per_vertex_io(var, b->shader->info.stage)) {
> + tail = tail->child;
> + }
> +
> + for (tail = tail->child; tail; tail = tail->child) {
> + if (tail->deref_type != nir_deref_type_array)
> + continue;
> +
> + nir_deref_array *arr = nir_deref_as_array(tail);
> + if (arr->deref_array_type == nir_deref_array_type_indirect)
> + return true;
> + }
> +
> + return false;
> +}
> +
> +/* Creates a mask of locations that contains arrays that are indexed via
> + * indirect indexing.
> + */
> +static void
> +create_indirects_mask(nir_shader *shader, uint64_t *indirects,
> + uint64_t *patch_indirects)
Shouldn't this take a nir_variable_mode to select either inputs or outputs?
Cheers,
Nicolai
> +{
> + nir_foreach_function(function, shader) {
> + if (function->impl) {
> + 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 *intr = nir_instr_as_intrinsic(instr);
> +
> + if (intr->intrinsic != nir_intrinsic_load_var &&
> + intr->intrinsic != nir_intrinsic_store_var &&
> + intr->intrinsic != nir_intrinsic_interp_var_at_centroid &&
> + intr->intrinsic != nir_intrinsic_interp_var_at_sample &&
> + intr->intrinsic != nir_intrinsic_interp_var_at_offset)
> + continue;
> +
> + nir_variable *var = intr->variables[0]->var;
> +
> + uint64_t loc_mask = 1 << var->data.location;
> + if (var->data.patch) {
> + if (deref_has_indirect(&b, var, intr->variables[0]))
> + patch_indirects[var->data.location_frac] |= loc_mask;
> + } else {
> + if (deref_has_indirect(&b, var, intr->variables[0]))
> + indirects[var->data.location_frac] |= loc_mask;
> + }
> + }
> + }
> + }
> + }
> +}
> +
> +static void
> +lower_io_arrays_to_elements(nir_shader *shader, nir_variable_mode mask,
> + uint64_t *indirects, uint64_t *patch_indirects,
> + struct hash_table *varyings)
> +{
> + nir_foreach_function(function, shader) {
> + if (function->impl) {
> + 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 *intr = nir_instr_as_intrinsic(instr);
> +
> + if (intr->intrinsic != nir_intrinsic_load_var &&
> + intr->intrinsic != nir_intrinsic_store_var &&
> + intr->intrinsic != nir_intrinsic_interp_var_at_centroid &&
> + intr->intrinsic != nir_intrinsic_interp_var_at_sample &&
> + intr->intrinsic != nir_intrinsic_interp_var_at_offset)
> + continue;
> +
> + nir_variable *var = intr->variables[0]->var;
> +
> + /* Skip indirects */
> + uint64_t loc_mask = 1 << var->data.location;
> + if (var->data.patch) {
> + if (patch_indirects[var->data.location_frac] & loc_mask)
> + continue;
> + } else {
> + if (indirects[var->data.location_frac] & loc_mask)
> + continue;
> + }
> +
> + nir_variable_mode mode = var->data.mode;
> +
> + const struct glsl_type *type = var->type;
> + if (nir_is_per_vertex_io(var, b.shader->info.stage)) {
> + assert(glsl_type_is_array(type));
> + type = glsl_get_array_element(type);
> + }
> +
> + /* Skip types we cannot split.
> + *
> + * TODO: Add support for struct splitting.
> + */
> + if ((!glsl_type_is_array(type) && !glsl_type_is_matrix(type))||
> + glsl_type_is_struct(glsl_without_array(type)))
> + continue;
> +
> + if (var->data.location < VARYING_SLOT_VAR0 &&
> + var->data.location >= 0)
> + continue;
> +
> + /* Don't bother splitting if we can't opt away any unused
> + * elements.
> + */
> + if (var->data.always_active_io)
> + continue;
> +
> + switch (intr->intrinsic) {
> + 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:
> + if ((mask & nir_var_shader_in && mode == nir_var_shader_in) ||
> + (mask & nir_var_shader_out && mode == nir_var_shader_out))
> + lower_array(&b, intr, var, varyings);
> + break;
> + default:
> + break;
> + }
> + }
> + }
> + }
> + }
> +}
> +
> +void
> +nir_lower_io_arrays_to_elements(nir_shader *producer, nir_shader *consumer)
> +{
> + struct hash_table *split_inputs =
> + _mesa_hash_table_create(NULL, _mesa_hash_pointer,
> + _mesa_key_pointer_equal);
> + struct hash_table *split_outputs =
> + _mesa_hash_table_create(NULL, _mesa_hash_pointer,
> + _mesa_key_pointer_equal);
> +
> + uint64_t indirects[4] = {0}, patch_indirects[4] = {0};
> + create_indirects_mask(producer, indirects, patch_indirects);
> + create_indirects_mask(consumer, indirects, patch_indirects);
> +
> + lower_io_arrays_to_elements(producer, nir_var_shader_out, indirects,
> + patch_indirects, split_outputs);
> +
> + lower_io_arrays_to_elements(consumer, nir_var_shader_in, indirects,
> + patch_indirects, split_inputs);
> +
> + /* Remove old input from the shaders inputs list */
> + struct hash_entry *entry;
> + hash_table_foreach(split_inputs, entry) {
> + nir_variable *var = (nir_variable *) entry->key;
> + exec_node_remove(&var->node);
> +
> + free(entry->data);
> + }
> +
> + /* Remove old output from the shaders outputs list */
> + hash_table_foreach(split_outputs, entry) {
> + nir_variable *var = (nir_variable *) entry->key;
> + exec_node_remove(&var->node);
> +
> + free(entry->data);
> + }
> +
> + _mesa_hash_table_destroy(split_inputs, NULL);
> + _mesa_hash_table_destroy(split_outputs, NULL);
> +}
>
--
Lerne, wie die Welt wirklich ist,
Aber vergiss niemals, wie sie sein sollte.
More information about the mesa-dev
mailing list