1 /*
2 * Copyright © 2018 Intel Corporation
3 *
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:
10 *
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
13 * Software.
14 *
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
21 * IN THE SOFTWARE.
22 */
23
24 #include "nir.h"
25 #include "nir_builder.h"
26
27 static bool
assert_ssa_def_is_not_1bit(nir_def * def,UNUSED void * unused)28 assert_ssa_def_is_not_1bit(nir_def *def, UNUSED void *unused)
29 {
30 assert(def->bit_size > 1);
31 return true;
32 }
33
34 static bool
rewrite_1bit_ssa_def_to_32bit(nir_def * def,void * _progress)35 rewrite_1bit_ssa_def_to_32bit(nir_def *def, void *_progress)
36 {
37 bool *progress = _progress;
38 if (def->bit_size == 1) {
39 def->bit_size = 32;
40 *progress = true;
41 }
42 return true;
43 }
44
45 static uint32_t
get_bool_convert_opcode(uint32_t dst_bit_size)46 get_bool_convert_opcode(uint32_t dst_bit_size)
47 {
48 switch (dst_bit_size) {
49 case 32:
50 return nir_op_i2i32;
51 case 16:
52 return nir_op_i2i16;
53 case 8:
54 return nir_op_i2i8;
55 default:
56 unreachable("invalid boolean bit-size");
57 }
58 }
59
60 static void
make_sources_canonical(nir_builder * b,nir_alu_instr * alu,uint32_t start_idx)61 make_sources_canonical(nir_builder *b, nir_alu_instr *alu, uint32_t start_idx)
62 {
63 /* TODO: for now we take the bit-size of the first source as the canonical
64 * form but we could try to be smarter.
65 */
66 const nir_op_info *op_info = &nir_op_infos[alu->op];
67 uint32_t bit_size = nir_src_bit_size(alu->src[start_idx].src);
68 for (uint32_t i = start_idx + 1; i < op_info->num_inputs; i++) {
69 if (nir_src_bit_size(alu->src[i].src) != bit_size) {
70 b->cursor = nir_before_instr(&alu->instr);
71 nir_op convert_op = get_bool_convert_opcode(bit_size);
72 nir_def *new_src =
73 nir_build_alu(b, convert_op, alu->src[i].src.ssa, NULL, NULL, NULL);
74 /* Retain the write mask and swizzle of the original instruction so
75 * that we don’t unnecessarily create a vectorized instruction.
76 */
77 nir_alu_instr *conv_instr =
78 nir_instr_as_alu(nir_builder_last_instr(b));
79 conv_instr->def.num_components =
80 alu->def.num_components;
81 memcpy(conv_instr->src[0].swizzle,
82 alu->src[i].swizzle,
83 sizeof(conv_instr->src[0].swizzle));
84 nir_src_rewrite(&alu->src[i].src, new_src);
85 /* The swizzle will have been handled by the conversion instruction
86 * so we can reset it back to the default
87 */
88 for (unsigned j = 0; j < NIR_MAX_VEC_COMPONENTS; j++)
89 alu->src[i].swizzle[j] = j;
90 }
91 }
92 }
93
94 static bool
lower_alu_instr(nir_builder * b,nir_alu_instr * alu)95 lower_alu_instr(nir_builder *b, nir_alu_instr *alu)
96 {
97 const nir_op_info *op_info = &nir_op_infos[alu->op];
98
99 /* For operations that can take multiple boolean sources we need to ensure
100 * that all booleans have the same bit-size
101 */
102 switch (alu->op) {
103 case nir_op_mov:
104 case nir_op_vec2:
105 case nir_op_vec3:
106 case nir_op_vec4:
107 case nir_op_vec5:
108 case nir_op_vec8:
109 case nir_op_vec16:
110 case nir_op_inot:
111 case nir_op_iand:
112 case nir_op_ior:
113 case nir_op_ixor:
114 if (alu->def.bit_size > 1)
115 return false; /* Not a boolean instruction */
116 FALLTHROUGH;
117
118 case nir_op_ball_fequal2:
119 case nir_op_ball_fequal3:
120 case nir_op_ball_fequal4:
121 case nir_op_bany_fnequal2:
122 case nir_op_bany_fnequal3:
123 case nir_op_bany_fnequal4:
124 case nir_op_ball_iequal2:
125 case nir_op_ball_iequal3:
126 case nir_op_ball_iequal4:
127 case nir_op_bany_inequal2:
128 case nir_op_bany_inequal3:
129 case nir_op_bany_inequal4:
130 case nir_op_ieq:
131 case nir_op_ine:
132 make_sources_canonical(b, alu, 0);
133 break;
134
135 case nir_op_bcsel:
136 /* bcsel may be choosing between boolean sources too */
137 if (alu->def.bit_size == 1)
138 make_sources_canonical(b, alu, 1);
139 break;
140
141 default:
142 break;
143 }
144
145 /* Now that we have a canonical boolean bit-size, go on and rewrite the
146 * instruction to match the canonical bit-size.
147 */
148 uint32_t bit_size = nir_src_bit_size(alu->src[0].src);
149 assert(bit_size > 1);
150
151 nir_op opcode = alu->op;
152 switch (opcode) {
153 case nir_op_mov:
154 case nir_op_vec2:
155 case nir_op_vec3:
156 case nir_op_vec4:
157 case nir_op_vec5:
158 case nir_op_vec8:
159 case nir_op_vec16:
160 case nir_op_inot:
161 case nir_op_iand:
162 case nir_op_ior:
163 case nir_op_ixor:
164 /* Nothing to do here, we do not specialize these opcodes by bit-size */
165 break;
166
167 case nir_op_b2b1:
168 /* Since the canonical bit size is the size of the src, it's a no-op */
169 opcode = nir_op_mov;
170 break;
171
172 case nir_op_b2b32:
173 /* For up-converting booleans, sign-extend */
174 opcode = nir_op_i2i32;
175 break;
176
177 case nir_op_flt:
178 opcode = bit_size == 8 ? nir_op_flt8 : bit_size == 16 ? nir_op_flt16
179 : nir_op_flt32;
180 break;
181
182 case nir_op_fge:
183 opcode = bit_size == 8 ? nir_op_fge8 : bit_size == 16 ? nir_op_fge16
184 : nir_op_fge32;
185 break;
186
187 case nir_op_feq:
188 opcode = bit_size == 8 ? nir_op_feq8 : bit_size == 16 ? nir_op_feq16
189 : nir_op_feq32;
190 break;
191
192 case nir_op_fneu:
193 opcode = bit_size == 8 ? nir_op_fneu8 : bit_size == 16 ? nir_op_fneu16
194 : nir_op_fneu32;
195 break;
196
197 case nir_op_ilt:
198 opcode = bit_size == 8 ? nir_op_ilt8 : bit_size == 16 ? nir_op_ilt16
199 : nir_op_ilt32;
200 break;
201
202 case nir_op_ige:
203 opcode = bit_size == 8 ? nir_op_ige8 : bit_size == 16 ? nir_op_ige16
204 : nir_op_ige32;
205 break;
206
207 case nir_op_ieq:
208 opcode = bit_size == 8 ? nir_op_ieq8 : bit_size == 16 ? nir_op_ieq16
209 : nir_op_ieq32;
210 break;
211
212 case nir_op_ine:
213 opcode = bit_size == 8 ? nir_op_ine8 : bit_size == 16 ? nir_op_ine16
214 : nir_op_ine32;
215 break;
216
217 case nir_op_ult:
218 opcode = bit_size == 8 ? nir_op_ult8 : bit_size == 16 ? nir_op_ult16
219 : nir_op_ult32;
220 break;
221
222 case nir_op_uge:
223 opcode = bit_size == 8 ? nir_op_uge8 : bit_size == 16 ? nir_op_uge16
224 : nir_op_uge32;
225 break;
226
227 case nir_op_ball_fequal2:
228 opcode = bit_size == 8 ? nir_op_b8all_fequal2 : bit_size == 16 ? nir_op_b16all_fequal2
229 : nir_op_b32all_fequal2;
230 break;
231
232 case nir_op_ball_fequal3:
233 opcode = bit_size == 8 ? nir_op_b8all_fequal3 : bit_size == 16 ? nir_op_b16all_fequal3
234 : nir_op_b32all_fequal3;
235 break;
236
237 case nir_op_ball_fequal4:
238 opcode = bit_size == 8 ? nir_op_b8all_fequal4 : bit_size == 16 ? nir_op_b16all_fequal4
239 : nir_op_b32all_fequal4;
240 break;
241
242 case nir_op_bany_fnequal2:
243 opcode = bit_size == 8 ? nir_op_b8any_fnequal2 : bit_size == 16 ? nir_op_b16any_fnequal2
244 : nir_op_b32any_fnequal2;
245 break;
246
247 case nir_op_bany_fnequal3:
248 opcode = bit_size == 8 ? nir_op_b8any_fnequal3 : bit_size == 16 ? nir_op_b16any_fnequal3
249 : nir_op_b32any_fnequal3;
250 break;
251
252 case nir_op_bany_fnequal4:
253 opcode = bit_size == 8 ? nir_op_b8any_fnequal4 : bit_size == 16 ? nir_op_b16any_fnequal4
254 : nir_op_b32any_fnequal4;
255 break;
256
257 case nir_op_ball_iequal2:
258 opcode = bit_size == 8 ? nir_op_b8all_iequal2 : bit_size == 16 ? nir_op_b16all_iequal2
259 : nir_op_b32all_iequal2;
260 break;
261
262 case nir_op_ball_iequal3:
263 opcode = bit_size == 8 ? nir_op_b8all_iequal3 : bit_size == 16 ? nir_op_b16all_iequal3
264 : nir_op_b32all_iequal3;
265 break;
266
267 case nir_op_ball_iequal4:
268 opcode = bit_size == 8 ? nir_op_b8all_iequal4 : bit_size == 16 ? nir_op_b16all_iequal4
269 : nir_op_b32all_iequal4;
270 break;
271
272 case nir_op_bany_inequal2:
273 opcode = bit_size == 8 ? nir_op_b8any_inequal2 : bit_size == 16 ? nir_op_b16any_inequal2
274 : nir_op_b32any_inequal2;
275 break;
276
277 case nir_op_bany_inequal3:
278 opcode = bit_size == 8 ? nir_op_b8any_inequal3 : bit_size == 16 ? nir_op_b16any_inequal3
279 : nir_op_b32any_inequal3;
280 break;
281
282 case nir_op_bany_inequal4:
283 opcode = bit_size == 8 ? nir_op_b8any_inequal4 : bit_size == 16 ? nir_op_b16any_inequal4
284 : nir_op_b32any_inequal4;
285 break;
286
287 case nir_op_bcsel:
288 opcode = bit_size == 8 ? nir_op_b8csel : bit_size == 16 ? nir_op_b16csel
289 : nir_op_b32csel;
290
291 /* The destination of the selection may have a different bit-size from
292 * the bcsel condition.
293 */
294 bit_size = nir_src_bit_size(alu->src[1].src);
295 break;
296
297 default:
298 assert(alu->def.bit_size > 1);
299 for (unsigned i = 0; i < op_info->num_inputs; i++)
300 assert(alu->src[i].src.ssa->bit_size > 1);
301 return false;
302 }
303
304 alu->op = opcode;
305
306 if (alu->def.bit_size == 1)
307 alu->def.bit_size = bit_size;
308
309 return true;
310 }
311
312 static bool
lower_load_const_instr(nir_load_const_instr * load)313 lower_load_const_instr(nir_load_const_instr *load)
314 {
315 bool progress = false;
316
317 if (load->def.bit_size > 1)
318 return progress;
319
320 /* TODO: It is not clear if there is any case in which we can ever hit
321 * this path, so for now we just provide a 32-bit default.
322 *
323 * TODO2: after some changed on nir_const_value and other on upstream, we
324 * removed the initialization of a general value like this:
325 * nir_const_value value = load->value
326 *
327 * to initialize per value component. Need to confirm if that is correct,
328 * but look at the TOO before.
329 */
330 for (unsigned i = 0; i < load->def.num_components; i++) {
331 load->value[i].u32 = load->value[i].b ? NIR_TRUE : NIR_FALSE;
332 load->def.bit_size = 32;
333 progress = true;
334 }
335
336 return progress;
337 }
338
339 static bool
lower_phi_instr(nir_builder * b,nir_phi_instr * phi)340 lower_phi_instr(nir_builder *b, nir_phi_instr *phi)
341 {
342 if (phi->def.bit_size != 1)
343 return false;
344
345 /* Ensure all phi sources have a canonical bit-size. We choose the
346 * bit-size of the first phi source as the canonical form.
347 *
348 * TODO: maybe we can be smarter about how we choose the canonical form.
349 */
350 uint32_t dst_bit_size = 0;
351 nir_foreach_phi_src(phi_src, phi) {
352 uint32_t src_bit_size = nir_src_bit_size(phi_src->src);
353 if (dst_bit_size == 0) {
354 dst_bit_size = src_bit_size;
355 } else if (src_bit_size != dst_bit_size) {
356 b->cursor = nir_before_src(&phi_src->src);
357 nir_op convert_op = get_bool_convert_opcode(dst_bit_size);
358 nir_def *new_src =
359 nir_build_alu(b, convert_op, phi_src->src.ssa, NULL, NULL, NULL);
360 nir_src_rewrite(&phi_src->src, new_src);
361 }
362 }
363
364 phi->def.bit_size = dst_bit_size;
365
366 return true;
367 }
368
369 static bool
lower_tex_instr(nir_tex_instr * tex)370 lower_tex_instr(nir_tex_instr *tex)
371 {
372 bool progress = false;
373 rewrite_1bit_ssa_def_to_32bit(&tex->def, &progress);
374 if (tex->dest_type == nir_type_bool1) {
375 tex->dest_type = nir_type_bool32;
376 progress = true;
377 }
378 return progress;
379 }
380
381 static bool
nir_lower_bool_to_bitsize_instr(nir_builder * b,nir_instr * instr,UNUSED void * cb_data)382 nir_lower_bool_to_bitsize_instr(nir_builder *b,
383 nir_instr *instr,
384 UNUSED void *cb_data)
385 {
386 switch (instr->type) {
387 case nir_instr_type_alu:
388 return lower_alu_instr(b, nir_instr_as_alu(instr));
389
390 case nir_instr_type_load_const:
391 return lower_load_const_instr(nir_instr_as_load_const(instr));
392
393 case nir_instr_type_phi:
394 return lower_phi_instr(b, nir_instr_as_phi(instr));
395
396 case nir_instr_type_undef:
397 case nir_instr_type_intrinsic: {
398 bool progress = false;
399 nir_foreach_def(instr, rewrite_1bit_ssa_def_to_32bit, &progress);
400 return progress;
401 }
402
403 case nir_instr_type_tex:
404 return lower_tex_instr(nir_instr_as_tex(instr));
405
406 default:
407 nir_foreach_def(instr, assert_ssa_def_is_not_1bit, NULL);
408 return false;
409 }
410 }
411
412 bool
nir_lower_bool_to_bitsize(nir_shader * shader)413 nir_lower_bool_to_bitsize(nir_shader *shader)
414 {
415 return nir_shader_instructions_pass(shader, nir_lower_bool_to_bitsize_instr,
416 nir_metadata_control_flow,
417 NULL);
418 }
419