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