2 * Copyright © 2017 Timothy Arceri
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
25 #include "nir_builder.h"
26 #include "nir_deref.h"
28 /** @file nir_lower_io_arrays_to_elements.c
30 * Split arrays/matrices with direct indexing into individual elements. This
31 * will allow optimisation passes to better clean up unused elements.
36 get_io_offset(nir_builder
*b
, nir_deref_instr
*deref
, nir_variable
*var
,
37 unsigned *element_index
, unsigned *xfb_offset
,
38 nir_ssa_def
**vertex_index
)
41 nir_deref_path_init(&path
, deref
, NULL
);
43 assert(path
.path
[0]->deref_type
== nir_deref_type_var
);
44 nir_deref_instr
**p
= &path
.path
[1];
46 /* For per-vertex input arrays (i.e. geometry shader inputs), skip the
47 * outermost array index. Process the rest normally.
49 if (nir_is_per_vertex_io(var
, b
->shader
->info
.stage
)) {
50 *vertex_index
= nir_ssa_for_src(b
, (*p
)->arr
.index
, 1);
57 if ((*p
)->deref_type
== nir_deref_type_array
) {
58 /* must not be indirect dereference */
59 unsigned index
= nir_src_as_uint((*p
)->arr
.index
);
61 unsigned size
= glsl_count_attribute_slots((*p
)->type
, false);
62 offset
+= size
* index
;
64 xfb_offset
+= index
* glsl_get_component_slots((*p
)->type
) * 4;
66 unsigned num_elements
= glsl_type_is_array((*p
)->type
) ?
67 glsl_get_aoa_size((*p
)->type
) : 1;
69 num_elements
*= glsl_type_is_matrix(glsl_without_array((*p
)->type
)) ?
70 glsl_get_matrix_columns(glsl_without_array((*p
)->type
)) : 1;
72 *element_index
+= num_elements
* index
;
73 } else if ((*p
)->deref_type
== nir_deref_type_struct
) {
74 /* TODO: we could also add struct splitting support to this pass */
79 nir_deref_path_finish(&path
);
84 static nir_variable
**
85 get_array_elements(struct hash_table
*ht
, nir_variable
*var
,
86 gl_shader_stage stage
)
88 nir_variable
**elements
;
89 struct hash_entry
*entry
= _mesa_hash_table_search(ht
, var
);
91 const struct glsl_type
*type
= var
->type
;
92 if (nir_is_per_vertex_io(var
, stage
)) {
93 assert(glsl_type_is_array(type
));
94 type
= glsl_get_array_element(type
);
97 unsigned num_elements
= glsl_type_is_array(type
) ?
98 glsl_get_aoa_size(type
) : 1;
100 num_elements
*= glsl_type_is_matrix(glsl_without_array(type
)) ?
101 glsl_get_matrix_columns(glsl_without_array(type
)) : 1;
103 elements
= (nir_variable
**) calloc(num_elements
, sizeof(nir_variable
*));
104 _mesa_hash_table_insert(ht
, var
, elements
);
106 elements
= (nir_variable
**) entry
->data
;
113 lower_array(nir_builder
*b
, nir_intrinsic_instr
*intr
, nir_variable
*var
,
114 struct hash_table
*varyings
)
116 b
->cursor
= nir_before_instr(&intr
->instr
);
118 nir_variable
**elements
=
119 get_array_elements(varyings
, var
, b
->shader
->info
.stage
);
121 nir_ssa_def
*vertex_index
= NULL
;
122 unsigned elements_index
= 0;
123 unsigned xfb_offset
= 0;
124 unsigned io_offset
= get_io_offset(b
, nir_src_as_deref(intr
->src
[0]),
125 var
, &elements_index
, &xfb_offset
,
128 nir_variable
*element
= elements
[elements_index
];
130 element
= nir_variable_clone(var
, b
->shader
);
131 element
->data
.location
= var
->data
.location
+ io_offset
;
133 if (var
->data
.explicit_offset
)
134 element
->data
.offset
= var
->data
.offset
+ xfb_offset
;
136 const struct glsl_type
*type
= glsl_without_array(element
->type
);
138 /* This pass also splits matrices so we need give them a new type. */
139 if (glsl_type_is_matrix(type
))
140 type
= glsl_get_column_type(type
);
142 if (nir_is_per_vertex_io(var
, b
->shader
->info
.stage
)) {
143 type
= glsl_array_type(type
, glsl_get_length(element
->type
),
144 glsl_get_explicit_stride(element
->type
));
147 element
->type
= type
;
148 elements
[elements_index
] = element
;
150 nir_shader_add_variable(b
->shader
, element
);
153 nir_deref_instr
*element_deref
= nir_build_deref_var(b
, element
);
155 if (nir_is_per_vertex_io(var
, b
->shader
->info
.stage
)) {
156 assert(vertex_index
);
157 element_deref
= nir_build_deref_array(b
, element_deref
, vertex_index
);
160 nir_intrinsic_instr
*element_intr
=
161 nir_intrinsic_instr_create(b
->shader
, intr
->intrinsic
);
162 element_intr
->num_components
= intr
->num_components
;
163 element_intr
->src
[0] = nir_src_for_ssa(&element_deref
->dest
.ssa
);
165 if (intr
->intrinsic
!= nir_intrinsic_store_deref
) {
166 nir_ssa_dest_init(&element_intr
->instr
, &element_intr
->dest
,
167 intr
->num_components
, intr
->dest
.ssa
.bit_size
, NULL
);
169 if (intr
->intrinsic
== nir_intrinsic_interp_deref_at_offset
||
170 intr
->intrinsic
== nir_intrinsic_interp_deref_at_sample
||
171 intr
->intrinsic
== nir_intrinsic_interp_deref_at_vertex
) {
172 nir_src_copy(&element_intr
->src
[1], &intr
->src
[1],
173 &element_intr
->instr
);
176 nir_ssa_def_rewrite_uses(&intr
->dest
.ssa
,
177 nir_src_for_ssa(&element_intr
->dest
.ssa
));
179 nir_intrinsic_set_write_mask(element_intr
,
180 nir_intrinsic_write_mask(intr
));
181 nir_src_copy(&element_intr
->src
[1], &intr
->src
[1],
182 &element_intr
->instr
);
185 nir_builder_instr_insert(b
, &element_intr
->instr
);
187 /* Remove the old load intrinsic */
188 nir_instr_remove(&intr
->instr
);
192 deref_has_indirect(nir_builder
*b
, nir_variable
*var
, nir_deref_path
*path
)
194 assert(path
->path
[0]->deref_type
== nir_deref_type_var
);
195 nir_deref_instr
**p
= &path
->path
[1];
197 if (nir_is_per_vertex_io(var
, b
->shader
->info
.stage
)) {
202 if ((*p
)->deref_type
!= nir_deref_type_array
)
205 if (!nir_src_is_const((*p
)->arr
.index
))
212 /* Creates a mask of locations that contains arrays that are indexed via
216 create_indirects_mask(nir_shader
*shader
,
217 BITSET_WORD
*indirects
, nir_variable_mode mode
)
219 nir_foreach_function(function
, shader
) {
220 if (function
->impl
) {
222 nir_builder_init(&b
, function
->impl
);
224 nir_foreach_block(block
, function
->impl
) {
225 nir_foreach_instr_safe(instr
, block
) {
227 if (instr
->type
!= nir_instr_type_intrinsic
)
230 nir_intrinsic_instr
*intr
= nir_instr_as_intrinsic(instr
);
232 if (intr
->intrinsic
!= nir_intrinsic_load_deref
&&
233 intr
->intrinsic
!= nir_intrinsic_store_deref
&&
234 intr
->intrinsic
!= nir_intrinsic_interp_deref_at_centroid
&&
235 intr
->intrinsic
!= nir_intrinsic_interp_deref_at_sample
&&
236 intr
->intrinsic
!= nir_intrinsic_interp_deref_at_offset
&&
237 intr
->intrinsic
!= nir_intrinsic_interp_deref_at_vertex
)
240 nir_deref_instr
*deref
= nir_src_as_deref(intr
->src
[0]);
241 if (deref
->mode
!= mode
)
244 nir_variable
*var
= nir_deref_instr_get_variable(deref
);
247 nir_deref_path_init(&path
, deref
, NULL
);
249 int loc
= var
->data
.location
* 4 + var
->data
.location_frac
;
250 if (deref_has_indirect(&b
, var
, &path
))
251 BITSET_SET(indirects
, loc
);
253 nir_deref_path_finish(&path
);
261 lower_io_arrays_to_elements(nir_shader
*shader
, nir_variable_mode mask
,
262 BITSET_WORD
*indirects
,
263 struct hash_table
*varyings
,
264 bool after_cross_stage_opts
)
266 nir_foreach_function(function
, shader
) {
267 if (function
->impl
) {
269 nir_builder_init(&b
, function
->impl
);
271 nir_foreach_block(block
, function
->impl
) {
272 nir_foreach_instr_safe(instr
, block
) {
273 if (instr
->type
!= nir_instr_type_intrinsic
)
276 nir_intrinsic_instr
*intr
= nir_instr_as_intrinsic(instr
);
278 if (intr
->intrinsic
!= nir_intrinsic_load_deref
&&
279 intr
->intrinsic
!= nir_intrinsic_store_deref
&&
280 intr
->intrinsic
!= nir_intrinsic_interp_deref_at_centroid
&&
281 intr
->intrinsic
!= nir_intrinsic_interp_deref_at_sample
&&
282 intr
->intrinsic
!= nir_intrinsic_interp_deref_at_offset
&&
283 intr
->intrinsic
!= nir_intrinsic_interp_deref_at_vertex
)
286 nir_deref_instr
*deref
= nir_src_as_deref(intr
->src
[0]);
287 if (!(deref
->mode
& mask
))
290 nir_variable
*var
= nir_deref_instr_get_variable(deref
);
292 /* Drivers assume compact arrays are, in fact, arrays. */
293 if (var
->data
.compact
)
296 /* Per-view variables are expected to remain arrays. */
297 if (var
->data
.per_view
)
301 int loc
= var
->data
.location
* 4 + var
->data
.location_frac
;
302 if (BITSET_TEST(indirects
, loc
))
305 nir_variable_mode mode
= var
->data
.mode
;
307 const struct glsl_type
*type
= var
->type
;
308 if (nir_is_per_vertex_io(var
, b
.shader
->info
.stage
)) {
309 assert(glsl_type_is_array(type
));
310 type
= glsl_get_array_element(type
);
313 /* Skip types we cannot split.
315 * TODO: Add support for struct splitting.
317 if ((!glsl_type_is_array(type
) && !glsl_type_is_matrix(type
))||
318 glsl_type_is_struct_or_ifc(glsl_without_array(type
)))
322 if (!after_cross_stage_opts
&&
323 var
->data
.location
< VARYING_SLOT_VAR0
&&
324 var
->data
.location
>= 0)
327 /* Don't bother splitting if we can't opt away any unused
330 if (!after_cross_stage_opts
&& var
->data
.always_active_io
)
333 switch (intr
->intrinsic
) {
334 case nir_intrinsic_interp_deref_at_centroid
:
335 case nir_intrinsic_interp_deref_at_sample
:
336 case nir_intrinsic_interp_deref_at_offset
:
337 case nir_intrinsic_interp_deref_at_vertex
:
338 case nir_intrinsic_load_deref
:
339 case nir_intrinsic_store_deref
:
340 if ((mask
& nir_var_shader_in
&& mode
== nir_var_shader_in
) ||
341 (mask
& nir_var_shader_out
&& mode
== nir_var_shader_out
))
342 lower_array(&b
, intr
, var
, varyings
);
354 nir_lower_io_arrays_to_elements_no_indirects(nir_shader
*shader
,
357 struct hash_table
*split_inputs
= _mesa_pointer_hash_table_create(NULL
);
358 struct hash_table
*split_outputs
= _mesa_pointer_hash_table_create(NULL
);
360 BITSET_DECLARE(indirects
, 4 * VARYING_SLOT_TESS_MAX
) = {0};
362 lower_io_arrays_to_elements(shader
, nir_var_shader_out
,
363 indirects
, split_outputs
, true);
366 lower_io_arrays_to_elements(shader
, nir_var_shader_in
,
367 indirects
, split_inputs
, true);
369 /* Remove old input from the shaders inputs list */
370 hash_table_foreach(split_inputs
, entry
) {
371 nir_variable
*var
= (nir_variable
*) entry
->key
;
372 exec_node_remove(&var
->node
);
378 /* Remove old output from the shaders outputs list */
379 hash_table_foreach(split_outputs
, entry
) {
380 nir_variable
*var
= (nir_variable
*) entry
->key
;
381 exec_node_remove(&var
->node
);
386 _mesa_hash_table_destroy(split_inputs
, NULL
);
387 _mesa_hash_table_destroy(split_outputs
, NULL
);
389 nir_remove_dead_derefs(shader
);
393 nir_lower_io_arrays_to_elements(nir_shader
*producer
, nir_shader
*consumer
)
395 struct hash_table
*split_inputs
= _mesa_pointer_hash_table_create(NULL
);
396 struct hash_table
*split_outputs
= _mesa_pointer_hash_table_create(NULL
);
398 BITSET_DECLARE(indirects
, 4 * VARYING_SLOT_TESS_MAX
) = {0};
400 create_indirects_mask(producer
, indirects
, nir_var_shader_out
);
401 create_indirects_mask(consumer
, indirects
, nir_var_shader_in
);
403 lower_io_arrays_to_elements(producer
, nir_var_shader_out
,
404 indirects
, split_outputs
, false);
406 lower_io_arrays_to_elements(consumer
, nir_var_shader_in
,
407 indirects
, split_inputs
, false);
409 /* Remove old input from the shaders inputs list */
410 hash_table_foreach(split_inputs
, entry
) {
411 nir_variable
*var
= (nir_variable
*) entry
->key
;
412 exec_node_remove(&var
->node
);
417 /* Remove old output from the shaders outputs list */
418 hash_table_foreach(split_outputs
, entry
) {
419 nir_variable
*var
= (nir_variable
*) entry
->key
;
420 exec_node_remove(&var
->node
);
425 _mesa_hash_table_destroy(split_inputs
, NULL
);
426 _mesa_hash_table_destroy(split_outputs
, NULL
);
428 nir_remove_dead_derefs(producer
);
429 nir_remove_dead_derefs(consumer
);