1 /* 2 * Copyright 2014 Broadcom 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 /** 25 * @file vc4_opt_algebraic.c 26 * 27 * This is the optimization pass for miscellaneous changes to instructions 28 * where we can simplify the operation by some knowledge about the specific 29 * operations. 30 * 31 * Mostly this will be a matter of turning things into MOVs so that they can 32 * later be copy-propagated out. 33 */ 34 35 #include "vc4_qir.h" 36 #include "util/u_math.h" 37 38 static bool debug; 39 40 static void 41 dump_from(struct vc4_compile *c, struct qinst *inst) 42 { 43 if (!debug) 44 return; 45 46 fprintf(stderr, "optimizing: "); 47 qir_dump_inst(c, inst); 48 fprintf(stderr, "\n"); 49 } 50 51 static void 52 dump_to(struct vc4_compile *c, struct qinst *inst) 53 { 54 if (!debug) 55 return; 56 57 fprintf(stderr, "to: "); 58 qir_dump_inst(c, inst); 59 fprintf(stderr, "\n"); 60 } 61 62 static bool 63 is_constant_value(struct vc4_compile *c, struct qreg reg, 64 uint32_t val) 65 { 66 if (reg.file == QFILE_UNIF && 67 !reg.pack && 68 c->uniform_contents[reg.index] == QUNIFORM_CONSTANT && 69 c->uniform_data[reg.index] == val) { 70 return true; 71 } 72 73 if (reg.file == QFILE_SMALL_IMM && reg.index == val) 74 return true; 75 76 return false; 77 } 78 79 static bool 80 is_zero(struct vc4_compile *c, struct qreg reg) 81 { 82 reg = qir_follow_movs(c, reg); 83 return is_constant_value(c, reg, 0); 84 } 85 86 static bool 87 is_1f(struct vc4_compile *c, struct qreg reg) 88 { 89 reg = qir_follow_movs(c, reg); 90 return is_constant_value(c, reg, fui(1.0)); 91 } 92 93 static void 94 replace_with_mov(struct vc4_compile *c, struct qinst *inst, struct qreg arg) 95 { 96 dump_from(c, inst); 97 98 inst->src[0] = arg; 99 if (qir_has_implicit_tex_uniform(inst)) 100 inst->src[1] = inst->src[qir_get_tex_uniform_src(inst)]; 101 102 if (qir_is_mul(inst)) 103 inst->op = QOP_MMOV; 104 else if (qir_is_float_input(inst)) 105 inst->op = QOP_FMOV; 106 else 107 inst->op = QOP_MOV; 108 dump_to(c, inst); 109 } 110 111 static bool 112 replace_x_0_with_x(struct vc4_compile *c, 113 struct qinst *inst, 114 int arg) 115 { 116 if (!is_zero(c, inst->src[arg])) 117 return false; 118 replace_with_mov(c, inst, inst->src[1 - arg]); 119 return true; 120 } 121 122 static bool 123 replace_x_0_with_0(struct vc4_compile *c, 124 struct qinst *inst, 125 int arg) 126 { 127 if (!is_zero(c, inst->src[arg])) 128 return false; 129 replace_with_mov(c, inst, inst->src[arg]); 130 return true; 131 } 132 133 static bool 134 fmul_replace_one(struct vc4_compile *c, 135 struct qinst *inst, 136 int arg) 137 { 138 if (!is_1f(c, inst->src[arg])) 139 return false; 140 replace_with_mov(c, inst, inst->src[1 - arg]); 141 return true; 142 } 143 144 bool 145 qir_opt_algebraic(struct vc4_compile *c) 146 { 147 bool progress = false; 148 149 qir_for_each_inst_inorder(inst, c) { 150 switch (inst->op) { 151 case QOP_FMIN: 152 if (is_1f(c, inst->src[1]) && 153 inst->src[0].pack >= QPU_UNPACK_8D_REP && 154 inst->src[0].pack <= QPU_UNPACK_8D) { 155 replace_with_mov(c, inst, inst->src[0]); 156 progress = true; 157 } 158 break; 159 160 case QOP_FMAX: 161 if (is_zero(c, inst->src[1]) && 162 inst->src[0].pack >= QPU_UNPACK_8D_REP && 163 inst->src[0].pack <= QPU_UNPACK_8D) { 164 replace_with_mov(c, inst, inst->src[0]); 165 progress = true; 166 } 167 break; 168 169 case QOP_FSUB: 170 case QOP_SUB: 171 if (is_zero(c, inst->src[1])) { 172 replace_with_mov(c, inst, inst->src[0]); 173 progress = true; 174 } 175 break; 176 177 case QOP_ADD: 178 /* Kernel validation requires that we use an actual 179 * add instruction. 180 */ 181 if (inst->dst.file != QFILE_TEX_S_DIRECT && 182 (replace_x_0_with_x(c, inst, 0) || 183 replace_x_0_with_x(c, inst, 1))) { 184 progress = true; 185 break; 186 } 187 break; 188 189 case QOP_FADD: 190 if (replace_x_0_with_x(c, inst, 0) || 191 replace_x_0_with_x(c, inst, 1)) { 192 progress = true; 193 break; 194 } 195 196 /* FADD(a, FSUB(0, b)) -> FSUB(a, b) */ 197 if (inst->src[1].file == QFILE_TEMP && 198 c->defs[inst->src[1].index] && 199 c->defs[inst->src[1].index]->op == QOP_FSUB) { 200 struct qinst *fsub = c->defs[inst->src[1].index]; 201 if (is_zero(c, fsub->src[0])) { 202 dump_from(c, inst); 203 inst->op = QOP_FSUB; 204 inst->src[1] = fsub->src[1]; 205 progress = true; 206 dump_to(c, inst); 207 break; 208 } 209 } 210 211 /* FADD(FSUB(0, b), a) -> FSUB(a, b) */ 212 if (inst->src[0].file == QFILE_TEMP && 213 c->defs[inst->src[0].index] && 214 c->defs[inst->src[0].index]->op == QOP_FSUB) { 215 struct qinst *fsub = c->defs[inst->src[0].index]; 216 if (is_zero(c, fsub->src[0])) { 217 dump_from(c, inst); 218 inst->op = QOP_FSUB; 219 inst->src[0] = inst->src[1]; 220 inst->src[1] = fsub->src[1]; 221 dump_to(c, inst); 222 progress = true; 223 break; 224 } 225 } 226 break; 227 228 case QOP_FMUL: 229 if (!inst->dst.pack && 230 (replace_x_0_with_0(c, inst, 0) || 231 replace_x_0_with_0(c, inst, 1) || 232 fmul_replace_one(c, inst, 0) || 233 fmul_replace_one(c, inst, 1))) { 234 progress = true; 235 break; 236 } 237 break; 238 239 case QOP_MUL24: 240 if (!inst->dst.pack && 241 (replace_x_0_with_0(c, inst, 0) || 242 replace_x_0_with_0(c, inst, 1))) { 243 progress = true; 244 break; 245 } 246 break; 247 248 case QOP_AND: 249 if (replace_x_0_with_0(c, inst, 0) || 250 replace_x_0_with_0(c, inst, 1)) { 251 progress = true; 252 break; 253 } 254 255 if (is_constant_value(c, inst->src[0], ~0)) { 256 replace_with_mov(c, inst, inst->src[1]); 257 progress = true; 258 break; 259 } 260 if (is_constant_value(c, inst->src[1], ~0)) { 261 replace_with_mov(c, inst, inst->src[0]); 262 progress = true; 263 break; 264 } 265 break; 266 267 case QOP_OR: 268 if (replace_x_0_with_x(c, inst, 0) || 269 replace_x_0_with_x(c, inst, 1)) { 270 progress = true; 271 break; 272 } 273 break; 274 275 case QOP_RCP: 276 if (is_1f(c, inst->src[0])) { 277 replace_with_mov(c, inst, inst->src[0]); 278 progress = true; 279 break; 280 } 281 break; 282 283 default: 284 break; 285 } 286 } 287 288 return progress; 289 } 290
