src/compiler/nir/nir_search_helpers.h

   1 /*
   2  * Copyright © 2016 Red Hat
   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  * Authors:
  24  *    Rob Clark <robclark@freedesktop.org>
  25  */
  26
  27 #ifndef _NIR_SEARCH_HELPERS_
  28 #define _NIR_SEARCH_HELPERS_
  29
  30 #include "nir.h"
  31 #include "util/bitscan.h"
  32 #include "nir_range_analysis.h"
  33 #include <math.h>
  34
  35 static inline bool
  36 is_pos_power_of_two(UNUSED struct hash_table *ht, nir_alu_instr *instr,
  37                     unsigned src, unsigned num_components,
  38                     const uint8_t *swizzle)
  39 {
  40    /* only constant srcs: */
  41    if (!nir_src_is_const(instr->src[src].src))
  42       return false;
  43
  44    for (unsigned i = 0; i < num_components; i++) {
  45       nir_alu_type type = nir_op_infos[instr->op].input_types[src];
  46       switch (nir_alu_type_get_base_type(type)) {
  47       case nir_type_int: {
  48          int64_t val = nir_src_comp_as_int(instr->src[src].src, swizzle[i]);
  49          if (val <= 0 || !util_is_power_of_two_or_zero64(val))
  50             return false;
  51          break;
  52       }
  53       case nir_type_uint: {
  54          uint64_t val = nir_src_comp_as_uint(instr->src[src].src, swizzle[i]);
  55          if (val == 0 || !util_is_power_of_two_or_zero64(val))
  56             return false;
  57          break;
  58       }
  59       default:
  60          return false;
  61       }
  62    }
  63
  64    return true;
  65 }
  66
  67 static inline bool
  68 is_neg_power_of_two(UNUSED struct hash_table *ht, nir_alu_instr *instr,
  69                     unsigned src, unsigned num_components,
  70                     const uint8_t *swizzle)
  71 {
  72    /* only constant srcs: */
  73    if (!nir_src_is_const(instr->src[src].src))
  74       return false;
  75
  76    for (unsigned i = 0; i < num_components; i++) {
  77       nir_alu_type type = nir_op_infos[instr->op].input_types[src];
  78       switch (nir_alu_type_get_base_type(type)) {
  79       case nir_type_int: {
  80          int64_t val = nir_src_comp_as_int(instr->src[src].src, swizzle[i]);
  81          if (val >= 0 || !util_is_power_of_two_or_zero64(-val))
  82             return false;
  83          break;
  84       }
  85       default:
  86          return false;
  87       }
  88    }
  89
  90    return true;
  91 }
  92
  93 #define MULTIPLE(test)                                                  \
  94 static inline bool                                                      \
  95 is_unsigned_multiple_of_ ## test(UNUSED struct hash_table *ht, nir_alu_instr *instr, \
  96                                  unsigned src, unsigned num_components, \
  97                                  const uint8_t *swizzle)                \
  98 {                                                                       \
  99    /* only constant srcs: */                                            \
 100    if (!nir_src_is_const(instr->src[src].src))                          \
 101       return false;                                                     \
 102                                                                         \
 103    for (unsigned i = 0; i < num_components; i++) {                      \
 104       uint64_t val = nir_src_comp_as_uint(instr->src[src].src, swizzle[i]); \
 105       if (val % test != 0)                                              \
 106          return false;                                                  \
 107    }                                                                    \
 108                                                                         \
 109    return true;                                                         \
 110 }
 111
 112 MULTIPLE(2)
 113 MULTIPLE(4)
 114 MULTIPLE(8)
 115 MULTIPLE(16)
 116 MULTIPLE(32)
 117 MULTIPLE(64)
 118
 119 static inline bool
 120 is_zero_to_one(UNUSED struct hash_table *ht, nir_alu_instr *instr, unsigned src,
 121                unsigned num_components,
 122                const uint8_t *swizzle)
 123 {
 124    /* only constant srcs: */
 125    if (!nir_src_is_const(instr->src[src].src))
 126       return false;
 127
 128    for (unsigned i = 0; i < num_components; i++) {
 129       switch (nir_op_infos[instr->op].input_types[src]) {
 130       case nir_type_float: {
 131          double val = nir_src_comp_as_float(instr->src[src].src, swizzle[i]);
 132          if (isnan(val) || val < 0.0f || val > 1.0f)
 133             return false;
 134          break;
 135       }
 136       default:
 137          return false;
 138       }
 139    }
 140
 141    return true;
 142 }
 143
 144 /**
 145  * Exclusive compare with (0, 1).
 146  *
 147  * This differs from \c is_zero_to_one because that function tests 0 <= src <=
 148  * 1 while this function tests 0 < src < 1.
 149  */
 150 static inline bool
 151 is_gt_0_and_lt_1(UNUSED struct hash_table *ht, nir_alu_instr *instr,
 152                  unsigned src, unsigned num_components,
 153                  const uint8_t *swizzle)
 154 {
 155    /* only constant srcs: */
 156    if (!nir_src_is_const(instr->src[src].src))
 157       return false;
 158
 159    for (unsigned i = 0; i < num_components; i++) {
 160       switch (nir_op_infos[instr->op].input_types[src]) {
 161       case nir_type_float: {
 162          double val = nir_src_comp_as_float(instr->src[src].src, swizzle[i]);
 163          if (isnan(val) || val <= 0.0f || val >= 1.0f)
 164             return false;
 165          break;
 166       }
 167       default:
 168          return false;
 169       }
 170    }
 171
 172    return true;
 173 }
 174
 175 static inline bool
 176 is_not_const_zero(UNUSED struct hash_table *ht, nir_alu_instr *instr,
 177                   unsigned src, unsigned num_components,
 178                   const uint8_t *swizzle)
 179 {
 180    if (nir_src_as_const_value(instr->src[src].src) == NULL)
 181       return true;
 182
 183    for (unsigned i = 0; i < num_components; i++) {
 184       nir_alu_type type = nir_op_infos[instr->op].input_types[src];
 185       switch (nir_alu_type_get_base_type(type)) {
 186       case nir_type_float:
 187          if (nir_src_comp_as_float(instr->src[src].src, swizzle[i]) == 0.0)
 188             return false;
 189          break;
 190       case nir_type_bool:
 191       case nir_type_int:
 192       case nir_type_uint:
 193          if (nir_src_comp_as_uint(instr->src[src].src, swizzle[i]) == 0)
 194             return false;
 195          break;
 196       default:
 197          return false;
 198       }
 199    }
 200
 201    return true;
 202 }
 203
 204 static inline bool
 205 is_not_const(UNUSED struct hash_table *ht, nir_alu_instr *instr, unsigned src,
 206              UNUSED unsigned num_components,
 207              UNUSED const uint8_t *swizzle)
 208 {
 209    return !nir_src_is_const(instr->src[src].src);
 210 }
 211
 212 static inline bool
 213 is_not_fmul(struct hash_table *ht, nir_alu_instr *instr, unsigned src,
 214             UNUSED unsigned num_components, UNUSED const uint8_t *swizzle)
 215 {
 216    nir_alu_instr *src_alu =
 217       nir_src_as_alu_instr(instr->src[src].src);
 218
 219    if (src_alu == NULL)
 220       return true;
 221
 222    if (src_alu->op == nir_op_fneg)
 223       return is_not_fmul(ht, src_alu, 0, 0, NULL);
 224
 225    return src_alu->op != nir_op_fmul;
 226 }
 227
 228 static inline bool
 229 is_fsign(nir_alu_instr *instr, unsigned src,
 230          UNUSED unsigned num_components, UNUSED const uint8_t *swizzle)
 231 {
 232    nir_alu_instr *src_alu =
 233       nir_src_as_alu_instr(instr->src[src].src);
 234
 235    if (src_alu == NULL)
 236       return false;
 237
 238    if (src_alu->op == nir_op_fneg)
 239       src_alu = nir_src_as_alu_instr(src_alu->src[0].src);
 240
 241    return src_alu != NULL && src_alu->op == nir_op_fsign;
 242 }
 243
 244 static inline bool
 245 is_not_const_and_not_fsign(struct hash_table *ht, nir_alu_instr *instr, unsigned src,
 246                            unsigned num_components, const uint8_t *swizzle)
 247 {
 248    return is_not_const(ht, instr, src, num_components, swizzle) &&
 249           !is_fsign(instr, src, num_components, swizzle);
 250 }
 251
 252 static inline bool
 253 is_used_once(nir_alu_instr *instr)
 254 {
 255    bool zero_if_use = list_is_empty(&instr->dest.dest.ssa.if_uses);
 256    bool zero_use = list_is_empty(&instr->dest.dest.ssa.uses);
 257
 258    if (zero_if_use && zero_use)
 259       return false;
 260
 261    if (!zero_if_use && list_is_singular(&instr->dest.dest.ssa.uses))
 262      return false;
 263
 264    if (!zero_use && list_is_singular(&instr->dest.dest.ssa.if_uses))
 265      return false;
 266
 267    if (!list_is_singular(&instr->dest.dest.ssa.if_uses) &&
 268        !list_is_singular(&instr->dest.dest.ssa.uses))
 269       return false;
 270
 271    return true;
 272 }
 273
 274 static inline bool
 275 is_used_by_if(nir_alu_instr *instr)
 276 {
 277    return !list_is_empty(&instr->dest.dest.ssa.if_uses);
 278 }
 279
 280 static inline bool
 281 is_not_used_by_if(nir_alu_instr *instr)
 282 {
 283    return list_is_empty(&instr->dest.dest.ssa.if_uses);
 284 }
 285
 286 static inline bool
 287 is_used_by_non_fsat(nir_alu_instr *instr)
 288 {
 289    nir_foreach_use(src, &instr->dest.dest.ssa) {
 290       const nir_instr *const user_instr = src->parent_instr;
 291
 292       if (user_instr->type != nir_instr_type_alu)
 293          return true;
 294
 295       const nir_alu_instr *const user_alu = nir_instr_as_alu(user_instr);
 296
 297       assert(instr != user_alu);
 298       if (user_alu->op != nir_op_fsat)
 299          return true;
 300    }
 301
 302    return false;
 303 }
 304
 305 /**
 306  * Returns true if a NIR ALU src represents a constant integer
 307  * of either 32 or 64 bits, and the higher word (bit-size / 2)
 308  * of all its components is zero.
 309  */
 310 static inline bool
 311 is_upper_half_zero(UNUSED struct hash_table *ht,
 312                    nir_alu_instr *instr, unsigned src,
 313                    unsigned num_components, const uint8_t *swizzle)
 314 {
 315    if (nir_src_as_const_value(instr->src[src].src) == NULL)
 316       return false;
 317
 318    for (unsigned i = 0; i < num_components; i++) {
 319       unsigned half_bit_size = nir_src_bit_size(instr->src[src].src) / 2;
 320       uint32_t high_bits = ((1 << half_bit_size) - 1) << half_bit_size;
 321       if ((nir_src_comp_as_uint(instr->src[src].src,
 322                                 swizzle[i]) & high_bits) != 0) {
 323          return false;
 324       }
 325    }
 326
 327    return true;
 328 }
 329
 330 /**
 331  * Returns true if a NIR ALU src represents a constant integer
 332  * of either 32 or 64 bits, and the lower word (bit-size / 2)
 333  * of all its components is zero.
 334  */
 335 static inline bool
 336 is_lower_half_zero(UNUSED struct hash_table *ht,
 337                    nir_alu_instr *instr, unsigned src,
 338                    unsigned num_components, const uint8_t *swizzle)
 339 {
 340    if (nir_src_as_const_value(instr->src[src].src) == NULL)
 341       return false;
 342
 343    for (unsigned i = 0; i < num_components; i++) {
 344       uint32_t low_bits =
 345          (1 << (nir_src_bit_size(instr->src[src].src) / 2)) - 1;
 346       if ((nir_src_comp_as_int(instr->src[src].src, swizzle[i]) & low_bits) != 0)
 347          return false;
 348    }
 349
 350    return true;
 351 }
 352
 353 static inline bool
 354 no_signed_wrap(nir_alu_instr *instr)
 355 {
 356    return instr->no_signed_wrap;
 357 }
 358
 359 static inline bool
 360 no_unsigned_wrap(nir_alu_instr *instr)
 361 {
 362    return instr->no_unsigned_wrap;
 363 }
 364
 365 static inline bool
 366 is_integral(struct hash_table *ht, nir_alu_instr *instr, unsigned src,
 367             UNUSED unsigned num_components, UNUSED const uint8_t *swizzle)
 368 {
 369    const struct ssa_result_range r = nir_analyze_range(ht, instr, src);
 370
 371    return r.is_integral;
 372 }
 373
 374 #define RELATION(r)                                                     \
 375 static inline bool                                                      \
 376 is_ ## r (struct hash_table *ht, nir_alu_instr *instr, unsigned src,                           \
 377           UNUSED unsigned num_components, UNUSED const uint8_t *swizzle) \
 378 {                                                                       \
 379    const struct ssa_result_range v = nir_analyze_range(ht, instr, src);  \
 380    return v.range == r;                                                 \
 381 }
 382
 383 RELATION(lt_zero)
 384 RELATION(le_zero)
 385 RELATION(gt_zero)
 386 RELATION(ge_zero)
 387 RELATION(ne_zero)
 388
 389 static inline bool
 390 is_not_negative(struct hash_table *ht, nir_alu_instr *instr, unsigned src,
 391                 UNUSED unsigned num_components, UNUSED const uint8_t *swizzle)
 392 {
 393    const struct ssa_result_range v = nir_analyze_range(ht, instr, src);
 394    return v.range == ge_zero || v.range == gt_zero || v.range == eq_zero;
 395 }
 396
 397 static inline bool
 398 is_not_positive(struct hash_table *ht, nir_alu_instr *instr, unsigned src,
 399                 UNUSED unsigned num_components, UNUSED const uint8_t *swizzle)
 400 {
 401    const struct ssa_result_range v = nir_analyze_range(ht, instr, src);
 402    return v.range == le_zero || v.range == lt_zero || v.range == eq_zero;
 403 }
 404
 405 static inline bool
 406 is_not_zero(struct hash_table *ht, nir_alu_instr *instr, unsigned src,
 407             UNUSED unsigned num_components, UNUSED const uint8_t *swizzle)
 408 {
 409    const struct ssa_result_range v = nir_analyze_range(ht, instr, src);
 410    return v.range == lt_zero || v.range == gt_zero || v.range == ne_zero;
 411 }
 412
 413 #endif /* _NIR_SEARCH_ */