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 <math.h>
  33
  34 static inline bool
  35 is_pos_power_of_two(nir_alu_instr *instr, unsigned src, unsigned num_components,
  36                     const uint8_t *swizzle)
  37 {
  38    /* only constant srcs: */
  39    if (!nir_src_is_const(instr->src[src].src))
  40       return false;
  41
  42    for (unsigned i = 0; i < num_components; i++) {
  43       switch (nir_op_infos[instr->op].input_types[src]) {
  44       case nir_type_int: {
  45          int64_t val = nir_src_comp_as_int(instr->src[src].src, swizzle[i]);
  46          if (val <= 0 || !util_is_power_of_two_or_zero64(val))
  47             return false;
  48          break;
  49       }
  50       case nir_type_uint: {
  51          uint64_t val = nir_src_comp_as_uint(instr->src[src].src, swizzle[i]);
  52          if (val == 0 || !util_is_power_of_two_or_zero64(val))
  53             return false;
  54          break;
  55       }
  56       default:
  57          return false;
  58       }
  59    }
  60
  61    return true;
  62 }
  63
  64 static inline bool
  65 is_neg_power_of_two(nir_alu_instr *instr, unsigned src, unsigned num_components,
  66                     const uint8_t *swizzle)
  67 {
  68    /* only constant srcs: */
  69    if (!nir_src_is_const(instr->src[src].src))
  70       return false;
  71
  72    for (unsigned i = 0; i < num_components; i++) {
  73       switch (nir_op_infos[instr->op].input_types[src]) {
  74       case nir_type_int: {
  75          int64_t val = nir_src_comp_as_int(instr->src[src].src, swizzle[i]);
  76          if (val >= 0 || !util_is_power_of_two_or_zero64(-val))
  77             return false;
  78          break;
  79       }
  80       default:
  81          return false;
  82       }
  83    }
  84
  85    return true;
  86 }
  87
  88 static inline bool
  89 is_zero_to_one(nir_alu_instr *instr, unsigned src, unsigned num_components,
  90                const uint8_t *swizzle)
  91 {
  92    /* only constant srcs: */
  93    if (!nir_src_is_const(instr->src[src].src))
  94       return false;
  95
  96    for (unsigned i = 0; i < num_components; i++) {
  97       switch (nir_op_infos[instr->op].input_types[src]) {
  98       case nir_type_float: {
  99          double val = nir_src_comp_as_float(instr->src[src].src, swizzle[i]);
 100          if (isnan(val) || val < 0.0f || val > 1.0f)
 101             return false;
 102          break;
 103       }
 104       default:
 105          return false;
 106       }
 107    }
 108
 109    return true;
 110 }
 111
 112 /**
 113  * Exclusive compare with (0, 1).
 114  *
 115  * This differs from \c is_zero_to_one because that function tests 0 <= src <=
 116  * 1 while this function tests 0 < src < 1.
 117  */
 118 static inline bool
 119 is_gt_0_and_lt_1(nir_alu_instr *instr, unsigned src, unsigned num_components,
 120                  const uint8_t *swizzle)
 121 {
 122    /* only constant srcs: */
 123    if (!nir_src_is_const(instr->src[src].src))
 124       return false;
 125
 126    for (unsigned i = 0; i < num_components; i++) {
 127       switch (nir_op_infos[instr->op].input_types[src]) {
 128       case nir_type_float: {
 129          double val = nir_src_comp_as_float(instr->src[src].src, swizzle[i]);
 130          if (isnan(val) || val <= 0.0f || val >= 1.0f)
 131             return false;
 132          break;
 133       }
 134       default:
 135          return false;
 136       }
 137    }
 138
 139    return true;
 140 }
 141
 142 static inline bool
 143 is_not_const_zero(nir_alu_instr *instr, unsigned src, unsigned num_components,
 144                   const uint8_t *swizzle)
 145 {
 146    if (nir_src_as_const_value(instr->src[src].src) == NULL)
 147       return true;
 148
 149    for (unsigned i = 0; i < num_components; i++) {
 150       switch (nir_op_infos[instr->op].input_types[src]) {
 151       case nir_type_float:
 152          if (nir_src_comp_as_float(instr->src[src].src, swizzle[i]) == 0.0)
 153             return false;
 154          break;
 155       case nir_type_bool:
 156       case nir_type_int:
 157       case nir_type_uint:
 158          if (nir_src_comp_as_uint(instr->src[src].src, swizzle[i]) == 0)
 159             return false;
 160          break;
 161       default:
 162          return false;
 163       }
 164    }
 165
 166    return true;
 167 }
 168
 169 static inline bool
 170 is_not_const(nir_alu_instr *instr, unsigned src, UNUSED unsigned num_components,
 171              UNUSED const uint8_t *swizzle)
 172 {
 173    return !nir_src_is_const(instr->src[src].src);
 174 }
 175
 176 static inline bool
 177 is_not_fmul(nir_alu_instr *instr, unsigned src,
 178             UNUSED unsigned num_components, UNUSED const uint8_t *swizzle)
 179 {
 180    nir_alu_instr *src_alu =
 181       nir_src_as_alu_instr(instr->src[src].src);
 182
 183    if (src_alu == NULL)
 184       return true;
 185
 186    if (src_alu->op == nir_op_fneg)
 187       return is_not_fmul(src_alu, 0, 0, NULL);
 188
 189    return src_alu->op != nir_op_fmul;
 190 }
 191
 192 static inline bool
 193 is_fsign(nir_alu_instr *instr, unsigned src,
 194          UNUSED unsigned num_components, UNUSED const uint8_t *swizzle)
 195 {
 196    nir_alu_instr *src_alu =
 197       nir_src_as_alu_instr(instr->src[src].src);
 198
 199    if (src_alu == NULL)
 200       return false;
 201
 202    if (src_alu->op == nir_op_fneg)
 203       src_alu = nir_src_as_alu_instr(src_alu->src[0].src);
 204
 205    return src_alu->op == nir_op_fsign;
 206 }
 207
 208 static inline bool
 209 is_not_const_and_not_fsign(nir_alu_instr *instr, unsigned src,
 210                            unsigned num_components, const uint8_t *swizzle)
 211 {
 212    return is_not_const(instr, src, num_components, swizzle) &&
 213           !is_fsign(instr, src, num_components, swizzle);
 214 }
 215
 216 static inline bool
 217 is_used_once(nir_alu_instr *instr)
 218 {
 219    bool zero_if_use = list_empty(&instr->dest.dest.ssa.if_uses);
 220    bool zero_use = list_empty(&instr->dest.dest.ssa.uses);
 221
 222    if (zero_if_use && zero_use)
 223       return false;
 224
 225    if (!zero_if_use && list_is_singular(&instr->dest.dest.ssa.uses))
 226      return false;
 227
 228    if (!zero_use && list_is_singular(&instr->dest.dest.ssa.if_uses))
 229      return false;
 230
 231    if (!list_is_singular(&instr->dest.dest.ssa.if_uses) &&
 232        !list_is_singular(&instr->dest.dest.ssa.uses))
 233       return false;
 234
 235    return true;
 236 }
 237
 238 static inline bool
 239 is_used_by_if(nir_alu_instr *instr)
 240 {
 241    return !list_empty(&instr->dest.dest.ssa.if_uses);
 242 }
 243
 244 static inline bool
 245 is_not_used_by_if(nir_alu_instr *instr)
 246 {
 247    return list_empty(&instr->dest.dest.ssa.if_uses);
 248 }
 249
 250 static inline bool
 251 is_used_by_non_fsat(nir_alu_instr *instr)
 252 {
 253    nir_foreach_use(src, &instr->dest.dest.ssa) {
 254       const nir_instr *const user_instr = src->parent_instr;
 255
 256       if (user_instr->type != nir_instr_type_alu)
 257          return true;
 258
 259       const nir_alu_instr *const user_alu = nir_instr_as_alu(user_instr);
 260
 261       assert(instr != user_alu);
 262       if (user_alu->op != nir_op_fsat)
 263          return true;
 264    }
 265
 266    return false;
 267 }
 268
 269 /**
 270  * Returns true if a NIR ALU src represents a constant integer
 271  * of either 32 or 64 bits, and the higher word (bit-size / 2)
 272  * of all its components is zero.
 273  */
 274 static inline bool
 275 is_upper_half_zero(nir_alu_instr *instr, unsigned src,
 276                    unsigned num_components, const uint8_t *swizzle)
 277 {
 278    if (nir_src_as_const_value(instr->src[src].src) == NULL)
 279       return false;
 280
 281    for (unsigned i = 0; i < num_components; i++) {
 282       unsigned half_bit_size = nir_src_bit_size(instr->src[src].src) / 2;
 283       uint32_t high_bits = ((1 << half_bit_size) - 1) << half_bit_size;
 284       if ((nir_src_comp_as_uint(instr->src[src].src,
 285                                 swizzle[i]) & high_bits) != 0) {
 286          return false;
 287       }
 288    }
 289
 290    return true;
 291 }
 292
 293 /**
 294  * Returns true if a NIR ALU src represents a constant integer
 295  * of either 32 or 64 bits, and the lower word (bit-size / 2)
 296  * of all its components is zero.
 297  */
 298 static inline bool
 299 is_lower_half_zero(nir_alu_instr *instr, unsigned src,
 300                    unsigned num_components, const uint8_t *swizzle)
 301 {
 302    if (nir_src_as_const_value(instr->src[src].src) == NULL)
 303       return false;
 304
 305    for (unsigned i = 0; i < num_components; i++) {
 306       uint32_t low_bits =
 307          (1 << (nir_src_bit_size(instr->src[src].src) / 2)) - 1;
 308       if ((nir_src_comp_as_int(instr->src[src].src, swizzle[i]) & low_bits) != 0)
 309          return false;
 310    }
 311
 312    return true;
 313 }
 314
 315 static inline bool
 316 no_signed_wrap(nir_alu_instr *instr)
 317 {
 318    return instr->no_signed_wrap;
 319 }
 320
 321 static inline bool
 322 no_unsigned_wrap(nir_alu_instr *instr)
 323 {
 324    return instr->no_unsigned_wrap;
 325 }
 326
 327 #endif /* _NIR_SEARCH_ */