1 /************************************************************************** 2 * 3 * Copyright 2009 VMware, Inc. 4 * All Rights Reserved. 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a 7 * copy of this software and associated documentation files (the 8 * "Software"), to deal in the Software without restriction, including 9 * without limitation the rights to use, copy, modify, merge, publish, 10 * distribute, sub license, and/or sell copies of the Software, and to 11 * permit persons to whom the Software is furnished to do so, subject to 12 * the following conditions: 13 * 14 * The above copyright notice and this permission notice (including the 15 * next paragraph) shall be included in all copies or substantial portions 16 * of the Software. 17 * 18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. 21 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR 22 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, 23 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE 24 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 25 * 26 **************************************************************************/ 27 28 29 /** 30 * @file 31 * Helper functions for packing/unpacking. 32 * 33 * Pack/unpacking is necessary for conversion between types of different 34 * bit width. 35 * 36 * They are also commonly used when an computation needs higher 37 * precision for the intermediate values. For example, if one needs the 38 * function: 39 * 40 * c = compute(a, b); 41 * 42 * to use more precision for intermediate results then one should implement it 43 * as: 44 * 45 * LLVMValueRef 46 * compute(LLVMBuilderRef builder struct lp_type type, LLVMValueRef a, LLVMValueRef b) 47 * { 48 * struct lp_type wide_type = lp_wider_type(type); 49 * LLVMValueRef al, ah, bl, bh, cl, ch, c; 50 * 51 * lp_build_unpack2(builder, type, wide_type, a, &al, &ah); 52 * lp_build_unpack2(builder, type, wide_type, b, &bl, &bh); 53 * 54 * cl = compute_half(al, bl); 55 * ch = compute_half(ah, bh); 56 * 57 * c = lp_build_pack2(bld->builder, wide_type, type, cl, ch); 58 * 59 * return c; 60 * } 61 * 62 * where compute_half() would do the computation for half the elements with 63 * twice the precision. 64 * 65 * @author Jose Fonseca <jfonseca (at) vmware.com> 66 */ 67 68 69 #include "util/u_debug.h" 70 #include "util/u_math.h" 71 #include "util/u_cpu_detect.h" 72 #include "util/u_memory.h" 73 74 #include "lp_bld_type.h" 75 #include "lp_bld_const.h" 76 #include "lp_bld_init.h" 77 #include "lp_bld_intr.h" 78 #include "lp_bld_arit.h" 79 #include "lp_bld_pack.h" 80 #include "lp_bld_swizzle.h" 81 82 83 /** 84 * Build shuffle vectors that match PUNPCKLxx and PUNPCKHxx instructions. 85 */ 86 static LLVMValueRef 87 lp_build_const_unpack_shuffle(struct gallivm_state *gallivm, 88 unsigned n, unsigned lo_hi) 89 { 90 LLVMValueRef elems[LP_MAX_VECTOR_LENGTH]; 91 unsigned i, j; 92 93 assert(n <= LP_MAX_VECTOR_LENGTH); 94 assert(lo_hi < 2); 95 96 /* TODO: cache results in a static table */ 97 98 for(i = 0, j = lo_hi*n/2; i < n; i += 2, ++j) { 99 elems[i + 0] = lp_build_const_int32(gallivm, 0 + j); 100 elems[i + 1] = lp_build_const_int32(gallivm, n + j); 101 } 102 103 return LLVMConstVector(elems, n); 104 } 105 106 /** 107 * Similar to lp_build_const_unpack_shuffle but for special AVX 256bit unpack. 108 * See comment above lp_build_interleave2_half for more details. 109 */ 110 static LLVMValueRef 111 lp_build_const_unpack_shuffle_half(struct gallivm_state *gallivm, 112 unsigned n, unsigned lo_hi) 113 { 114 LLVMValueRef elems[LP_MAX_VECTOR_LENGTH]; 115 unsigned i, j; 116 117 assert(n <= LP_MAX_VECTOR_LENGTH); 118 assert(lo_hi < 2); 119 120 for (i = 0, j = lo_hi*(n/4); i < n; i += 2, ++j) { 121 if (i == (n / 2)) 122 j += n / 4; 123 124 elems[i + 0] = lp_build_const_int32(gallivm, 0 + j); 125 elems[i + 1] = lp_build_const_int32(gallivm, n + j); 126 } 127 128 return LLVMConstVector(elems, n); 129 } 130 131 /** 132 * Similar to lp_build_const_unpack_shuffle_half, but for AVX512 133 * See comment above lp_build_interleave2_half for more details. 134 */ 135 static LLVMValueRef 136 lp_build_const_unpack_shuffle_16wide(struct gallivm_state *gallivm, 137 unsigned lo_hi) 138 { 139 LLVMValueRef elems[LP_MAX_VECTOR_LENGTH]; 140 unsigned i, j; 141 142 assert(lo_hi < 2); 143 144 // for the following lo_hi setting, convert 0 -> f to: 145 // 0: 0 16 4 20 8 24 12 28 1 17 5 21 9 25 13 29 146 // 1: 2 18 6 22 10 26 14 30 3 19 7 23 11 27 15 31 147 for (i = 0; i < 16; i++) { 148 j = ((i&0x06)<<1) + ((i&1)<<4) + (i>>3) + (lo_hi<<1); 149 150 elems[i] = lp_build_const_int32(gallivm, j); 151 } 152 153 return LLVMConstVector(elems, 16); 154 } 155 156 /** 157 * Build shuffle vectors that match PACKxx (SSE) instructions or 158 * VPERM (Altivec). 159 */ 160 static LLVMValueRef 161 lp_build_const_pack_shuffle(struct gallivm_state *gallivm, unsigned n) 162 { 163 LLVMValueRef elems[LP_MAX_VECTOR_LENGTH]; 164 unsigned i; 165 166 assert(n <= LP_MAX_VECTOR_LENGTH); 167 168 for(i = 0; i < n; ++i) 169 #ifdef PIPE_ARCH_LITTLE_ENDIAN 170 elems[i] = lp_build_const_int32(gallivm, 2*i); 171 #else 172 elems[i] = lp_build_const_int32(gallivm, 2*i+1); 173 #endif 174 175 return LLVMConstVector(elems, n); 176 } 177 178 /** 179 * Return a vector with elements src[start:start+size] 180 * Most useful for getting half the values out of a 256bit sized vector, 181 * otherwise may cause data rearrangement to happen. 182 */ 183 LLVMValueRef 184 lp_build_extract_range(struct gallivm_state *gallivm, 185 LLVMValueRef src, 186 unsigned start, 187 unsigned size) 188 { 189 LLVMValueRef elems[LP_MAX_VECTOR_LENGTH]; 190 unsigned i; 191 192 assert(size <= ARRAY_SIZE(elems)); 193 194 for (i = 0; i < size; ++i) 195 elems[i] = lp_build_const_int32(gallivm, i + start); 196 197 if (size == 1) { 198 return LLVMBuildExtractElement(gallivm->builder, src, elems[0], ""); 199 } 200 else { 201 return LLVMBuildShuffleVector(gallivm->builder, src, src, 202 LLVMConstVector(elems, size), ""); 203 } 204 } 205 206 /** 207 * Concatenates several (must be a power of 2) vectors (of same type) 208 * into a larger one. 209 * Most useful for building up a 256bit sized vector out of two 128bit ones. 210 */ 211 LLVMValueRef 212 lp_build_concat(struct gallivm_state *gallivm, 213 LLVMValueRef src[], 214 struct lp_type src_type, 215 unsigned num_vectors) 216 { 217 unsigned new_length, i; 218 LLVMValueRef tmp[LP_MAX_VECTOR_LENGTH/2]; 219 LLVMValueRef shuffles[LP_MAX_VECTOR_LENGTH]; 220 221 assert(src_type.length * num_vectors <= ARRAY_SIZE(shuffles)); 222 assert(util_is_power_of_two(num_vectors)); 223 224 new_length = src_type.length; 225 226 for (i = 0; i < num_vectors; i++) 227 tmp[i] = src[i]; 228 229 while (num_vectors > 1) { 230 num_vectors >>= 1; 231 new_length <<= 1; 232 for (i = 0; i < new_length; i++) { 233 shuffles[i] = lp_build_const_int32(gallivm, i); 234 } 235 for (i = 0; i < num_vectors; i++) { 236 tmp[i] = LLVMBuildShuffleVector(gallivm->builder, tmp[i*2], tmp[i*2 + 1], 237 LLVMConstVector(shuffles, new_length), ""); 238 } 239 } 240 241 return tmp[0]; 242 } 243 244 245 /** 246 * Combines vectors to reduce from num_srcs to num_dsts. 247 * Returns the number of src vectors concatenated in a single dst. 248 * 249 * num_srcs must be exactly divisible by num_dsts. 250 * 251 * e.g. For num_srcs = 4 and src = [x, y, z, w] 252 * num_dsts = 1 dst = [xyzw] return = 4 253 * num_dsts = 2 dst = [xy, zw] return = 2 254 */ 255 int 256 lp_build_concat_n(struct gallivm_state *gallivm, 257 struct lp_type src_type, 258 LLVMValueRef *src, 259 unsigned num_srcs, 260 LLVMValueRef *dst, 261 unsigned num_dsts) 262 { 263 int size = num_srcs / num_dsts; 264 unsigned i; 265 266 assert(num_srcs >= num_dsts); 267 assert((num_srcs % size) == 0); 268 269 if (num_srcs == num_dsts) { 270 for (i = 0; i < num_dsts; ++i) { 271 dst[i] = src[i]; 272 } 273 return 1; 274 } 275 276 for (i = 0; i < num_dsts; ++i) { 277 dst[i] = lp_build_concat(gallivm, &src[i * size], src_type, size); 278 } 279 280 return size; 281 } 282 283 284 /** 285 * Un-interleave vector. 286 * This will return a vector consisting of every second element 287 * (depending on lo_hi, beginning at 0 or 1). 288 * The returned vector size (elems and width) will only be half 289 * that of the source vector. 290 */ 291 LLVMValueRef 292 lp_build_uninterleave1(struct gallivm_state *gallivm, 293 unsigned num_elems, 294 LLVMValueRef a, 295 unsigned lo_hi) 296 { 297 LLVMValueRef shuffle, elems[LP_MAX_VECTOR_LENGTH]; 298 unsigned i; 299 assert(num_elems <= LP_MAX_VECTOR_LENGTH); 300 301 for (i = 0; i < num_elems / 2; ++i) 302 elems[i] = lp_build_const_int32(gallivm, 2*i + lo_hi); 303 304 shuffle = LLVMConstVector(elems, num_elems / 2); 305 306 return LLVMBuildShuffleVector(gallivm->builder, a, a, shuffle, ""); 307 } 308 309 310 /** 311 * Interleave vector elements. 312 * 313 * Matches the PUNPCKLxx and PUNPCKHxx SSE instructions 314 * (but not for 256bit AVX vectors). 315 */ 316 LLVMValueRef 317 lp_build_interleave2(struct gallivm_state *gallivm, 318 struct lp_type type, 319 LLVMValueRef a, 320 LLVMValueRef b, 321 unsigned lo_hi) 322 { 323 LLVMValueRef shuffle; 324 325 if (type.length == 2 && type.width == 128 && util_cpu_caps.has_avx) { 326 /* 327 * XXX: This is a workaround for llvm code generation deficiency. Strangely 328 * enough, while this needs vinsertf128/vextractf128 instructions (hence 329 * a natural match when using 2x128bit vectors) the "normal" unpack shuffle 330 * generates code ranging from atrocious (llvm 3.1) to terrible (llvm 3.2, 3.3). 331 * So use some different shuffles instead (the exact shuffles don't seem to 332 * matter, as long as not using 128bit wide vectors, works with 8x32 or 4x64). 333 */ 334 struct lp_type tmp_type = type; 335 LLVMValueRef srchalf[2], tmpdst; 336 tmp_type.length = 4; 337 tmp_type.width = 64; 338 a = LLVMBuildBitCast(gallivm->builder, a, lp_build_vec_type(gallivm, tmp_type), ""); 339 b = LLVMBuildBitCast(gallivm->builder, b, lp_build_vec_type(gallivm, tmp_type), ""); 340 srchalf[0] = lp_build_extract_range(gallivm, a, lo_hi * 2, 2); 341 srchalf[1] = lp_build_extract_range(gallivm, b, lo_hi * 2, 2); 342 tmp_type.length = 2; 343 tmpdst = lp_build_concat(gallivm, srchalf, tmp_type, 2); 344 return LLVMBuildBitCast(gallivm->builder, tmpdst, lp_build_vec_type(gallivm, type), ""); 345 } 346 347 shuffle = lp_build_const_unpack_shuffle(gallivm, type.length, lo_hi); 348 349 return LLVMBuildShuffleVector(gallivm->builder, a, b, shuffle, ""); 350 } 351 352 /** 353 * Interleave vector elements but with 256 (or 512) bit, 354 * treats it as interleave with 2 concatenated 128 (or 256) bit vectors. 355 * 356 * This differs to lp_build_interleave2 as that function would do the following (for lo): 357 * a0 b0 a1 b1 a2 b2 a3 b3, and this does not compile into an AVX unpack instruction. 358 * 359 * 360 * An example interleave 8x float with 8x float on AVX 256bit unpack: 361 * a0 a1 a2 a3 a4 a5 a6 a7 <-> b0 b1 b2 b3 b4 b5 b6 b7 362 * 363 * Equivalent to interleaving 2x 128 bit vectors 364 * a0 a1 a2 a3 <-> b0 b1 b2 b3 concatenated with a4 a5 a6 a7 <-> b4 b5 b6 b7 365 * 366 * So interleave-lo would result in: 367 * a0 b0 a1 b1 a4 b4 a5 b5 368 * 369 * And interleave-hi would result in: 370 * a2 b2 a3 b3 a6 b6 a7 b7 371 * 372 * For 512 bits, the following are true: 373 * 374 * Interleave-lo would result in (capital letters denote hex indices): 375 * a0 b0 a1 b1 a4 b4 a5 b5 a8 b8 a9 b9 aC bC aD bD 376 * 377 * Interleave-hi would result in: 378 * a2 b2 a3 b3 a6 b6 a7 b7 aA bA aB bB aE bE aF bF 379 */ 380 LLVMValueRef 381 lp_build_interleave2_half(struct gallivm_state *gallivm, 382 struct lp_type type, 383 LLVMValueRef a, 384 LLVMValueRef b, 385 unsigned lo_hi) 386 { 387 if (type.length * type.width == 256) { 388 LLVMValueRef shuffle = lp_build_const_unpack_shuffle_half(gallivm, type.length, lo_hi); 389 return LLVMBuildShuffleVector(gallivm->builder, a, b, shuffle, ""); 390 } else if ((type.length == 16) && (type.width == 32)) { 391 LLVMValueRef shuffle = lp_build_const_unpack_shuffle_16wide(gallivm, lo_hi); 392 return LLVMBuildShuffleVector(gallivm->builder, a, b, shuffle, ""); 393 } else { 394 return lp_build_interleave2(gallivm, type, a, b, lo_hi); 395 } 396 } 397 398 399 /** 400 * Double the bit width. 401 * 402 * This will only change the number of bits the values are represented, not the 403 * values themselves. 404 * 405 */ 406 void 407 lp_build_unpack2(struct gallivm_state *gallivm, 408 struct lp_type src_type, 409 struct lp_type dst_type, 410 LLVMValueRef src, 411 LLVMValueRef *dst_lo, 412 LLVMValueRef *dst_hi) 413 { 414 LLVMBuilderRef builder = gallivm->builder; 415 LLVMValueRef msb; 416 LLVMTypeRef dst_vec_type; 417 418 assert(!src_type.floating); 419 assert(!dst_type.floating); 420 assert(dst_type.width == src_type.width * 2); 421 assert(dst_type.length * 2 == src_type.length); 422 423 if(dst_type.sign && src_type.sign) { 424 /* Replicate the sign bit in the most significant bits */ 425 msb = LLVMBuildAShr(builder, src, lp_build_const_int_vec(gallivm, src_type, src_type.width - 1), ""); 426 } 427 else 428 /* Most significant bits always zero */ 429 msb = lp_build_zero(gallivm, src_type); 430 431 /* Interleave bits */ 432 #ifdef PIPE_ARCH_LITTLE_ENDIAN 433 *dst_lo = lp_build_interleave2(gallivm, src_type, src, msb, 0); 434 *dst_hi = lp_build_interleave2(gallivm, src_type, src, msb, 1); 435 436 #else 437 *dst_lo = lp_build_interleave2(gallivm, src_type, msb, src, 0); 438 *dst_hi = lp_build_interleave2(gallivm, src_type, msb, src, 1); 439 #endif 440 441 /* Cast the result into the new type (twice as wide) */ 442 443 dst_vec_type = lp_build_vec_type(gallivm, dst_type); 444 445 *dst_lo = LLVMBuildBitCast(builder, *dst_lo, dst_vec_type, ""); 446 *dst_hi = LLVMBuildBitCast(builder, *dst_hi, dst_vec_type, ""); 447 } 448 449 450 /** 451 * Double the bit width, with an order which fits the cpu nicely. 452 * 453 * This will only change the number of bits the values are represented, not the 454 * values themselves. 455 * 456 * The order of the results is not guaranteed, other than it will match 457 * the corresponding lp_build_pack2_native call. 458 */ 459 void 460 lp_build_unpack2_native(struct gallivm_state *gallivm, 461 struct lp_type src_type, 462 struct lp_type dst_type, 463 LLVMValueRef src, 464 LLVMValueRef *dst_lo, 465 LLVMValueRef *dst_hi) 466 { 467 LLVMBuilderRef builder = gallivm->builder; 468 LLVMValueRef msb; 469 LLVMTypeRef dst_vec_type; 470 471 assert(!src_type.floating); 472 assert(!dst_type.floating); 473 assert(dst_type.width == src_type.width * 2); 474 assert(dst_type.length * 2 == src_type.length); 475 476 if(dst_type.sign && src_type.sign) { 477 /* Replicate the sign bit in the most significant bits */ 478 msb = LLVMBuildAShr(builder, src, 479 lp_build_const_int_vec(gallivm, src_type, src_type.width - 1), ""); 480 } 481 else 482 /* Most significant bits always zero */ 483 msb = lp_build_zero(gallivm, src_type); 484 485 /* Interleave bits */ 486 #ifdef PIPE_ARCH_LITTLE_ENDIAN 487 if (src_type.length * src_type.width == 256 && util_cpu_caps.has_avx2) { 488 *dst_lo = lp_build_interleave2_half(gallivm, src_type, src, msb, 0); 489 *dst_hi = lp_build_interleave2_half(gallivm, src_type, src, msb, 1); 490 } else { 491 *dst_lo = lp_build_interleave2(gallivm, src_type, src, msb, 0); 492 *dst_hi = lp_build_interleave2(gallivm, src_type, src, msb, 1); 493 } 494 #else 495 *dst_lo = lp_build_interleave2(gallivm, src_type, msb, src, 0); 496 *dst_hi = lp_build_interleave2(gallivm, src_type, msb, src, 1); 497 #endif 498 499 /* Cast the result into the new type (twice as wide) */ 500 501 dst_vec_type = lp_build_vec_type(gallivm, dst_type); 502 503 *dst_lo = LLVMBuildBitCast(builder, *dst_lo, dst_vec_type, ""); 504 *dst_hi = LLVMBuildBitCast(builder, *dst_hi, dst_vec_type, ""); 505 } 506 507 508 /** 509 * Expand the bit width. 510 * 511 * This will only change the number of bits the values are represented, not the 512 * values themselves. 513 */ 514 void 515 lp_build_unpack(struct gallivm_state *gallivm, 516 struct lp_type src_type, 517 struct lp_type dst_type, 518 LLVMValueRef src, 519 LLVMValueRef *dst, unsigned num_dsts) 520 { 521 unsigned num_tmps; 522 unsigned i; 523 524 /* Register width must remain constant */ 525 assert(src_type.width * src_type.length == dst_type.width * dst_type.length); 526 527 /* We must not loose or gain channels. Only precision */ 528 assert(src_type.length == dst_type.length * num_dsts); 529 530 num_tmps = 1; 531 dst[0] = src; 532 533 while(src_type.width < dst_type.width) { 534 struct lp_type tmp_type = src_type; 535 536 tmp_type.width *= 2; 537 tmp_type.length /= 2; 538 539 for(i = num_tmps; i--; ) { 540 lp_build_unpack2(gallivm, src_type, tmp_type, dst[i], &dst[2*i + 0], 541 &dst[2*i + 1]); 542 } 543 544 src_type = tmp_type; 545 546 num_tmps *= 2; 547 } 548 549 assert(num_tmps == num_dsts); 550 } 551 552 553 /** 554 * Non-interleaved pack. 555 * 556 * This will move values as 557 * (LSB) (MSB) 558 * lo = l0 __ l1 __ l2 __.. __ ln __ 559 * hi = h0 __ h1 __ h2 __.. __ hn __ 560 * res = l0 l1 l2 .. ln h0 h1 h2 .. hn 561 * 562 * This will only change the number of bits the values are represented, not the 563 * values themselves. 564 * 565 * It is assumed the values are already clamped into the destination type range. 566 * Values outside that range will produce undefined results. Use 567 * lp_build_packs2 instead. 568 */ 569 LLVMValueRef 570 lp_build_pack2(struct gallivm_state *gallivm, 571 struct lp_type src_type, 572 struct lp_type dst_type, 573 LLVMValueRef lo, 574 LLVMValueRef hi) 575 { 576 LLVMBuilderRef builder = gallivm->builder; 577 LLVMTypeRef dst_vec_type = lp_build_vec_type(gallivm, dst_type); 578 LLVMValueRef shuffle; 579 LLVMValueRef res = NULL; 580 struct lp_type intr_type = dst_type; 581 582 assert(!src_type.floating); 583 assert(!dst_type.floating); 584 assert(src_type.width == dst_type.width * 2); 585 assert(src_type.length * 2 == dst_type.length); 586 587 /* Check for special cases first */ 588 if ((util_cpu_caps.has_sse2 || util_cpu_caps.has_altivec) && 589 src_type.width * src_type.length >= 128) { 590 const char *intrinsic = NULL; 591 boolean swap_intrinsic_operands = FALSE; 592 593 switch(src_type.width) { 594 case 32: 595 if (util_cpu_caps.has_sse2) { 596 if (dst_type.sign) { 597 intrinsic = "llvm.x86.sse2.packssdw.128"; 598 } else { 599 if (util_cpu_caps.has_sse4_1) { 600 intrinsic = "llvm.x86.sse41.packusdw"; 601 } 602 } 603 } else if (util_cpu_caps.has_altivec) { 604 if (dst_type.sign) { 605 intrinsic = "llvm.ppc.altivec.vpkswss"; 606 } else { 607 intrinsic = "llvm.ppc.altivec.vpkuwus"; 608 } 609 #ifdef PIPE_ARCH_LITTLE_ENDIAN 610 swap_intrinsic_operands = TRUE; 611 #endif 612 } 613 break; 614 case 16: 615 if (dst_type.sign) { 616 if (util_cpu_caps.has_sse2) { 617 intrinsic = "llvm.x86.sse2.packsswb.128"; 618 } else if (util_cpu_caps.has_altivec) { 619 intrinsic = "llvm.ppc.altivec.vpkshss"; 620 #ifdef PIPE_ARCH_LITTLE_ENDIAN 621 swap_intrinsic_operands = TRUE; 622 #endif 623 } 624 } else { 625 if (util_cpu_caps.has_sse2) { 626 intrinsic = "llvm.x86.sse2.packuswb.128"; 627 } else if (util_cpu_caps.has_altivec) { 628 intrinsic = "llvm.ppc.altivec.vpkshus"; 629 #ifdef PIPE_ARCH_LITTLE_ENDIAN 630 swap_intrinsic_operands = TRUE; 631 #endif 632 } 633 } 634 break; 635 /* default uses generic shuffle below */ 636 } 637 if (intrinsic) { 638 if (src_type.width * src_type.length == 128) { 639 LLVMTypeRef intr_vec_type = lp_build_vec_type(gallivm, intr_type); 640 if (swap_intrinsic_operands) { 641 res = lp_build_intrinsic_binary(builder, intrinsic, intr_vec_type, hi, lo); 642 } else { 643 res = lp_build_intrinsic_binary(builder, intrinsic, intr_vec_type, lo, hi); 644 } 645 if (dst_vec_type != intr_vec_type) { 646 res = LLVMBuildBitCast(builder, res, dst_vec_type, ""); 647 } 648 } 649 else { 650 int num_split = src_type.width * src_type.length / 128; 651 int i; 652 int nlen = 128 / src_type.width; 653 int lo_off = swap_intrinsic_operands ? nlen : 0; 654 int hi_off = swap_intrinsic_operands ? 0 : nlen; 655 struct lp_type ndst_type = lp_type_unorm(dst_type.width, 128); 656 struct lp_type nintr_type = lp_type_unorm(intr_type.width, 128); 657 LLVMValueRef tmpres[LP_MAX_VECTOR_WIDTH / 128]; 658 LLVMValueRef tmplo, tmphi; 659 LLVMTypeRef ndst_vec_type = lp_build_vec_type(gallivm, ndst_type); 660 LLVMTypeRef nintr_vec_type = lp_build_vec_type(gallivm, nintr_type); 661 662 assert(num_split <= LP_MAX_VECTOR_WIDTH / 128); 663 664 for (i = 0; i < num_split / 2; i++) { 665 tmplo = lp_build_extract_range(gallivm, 666 lo, i*nlen*2 + lo_off, nlen); 667 tmphi = lp_build_extract_range(gallivm, 668 lo, i*nlen*2 + hi_off, nlen); 669 tmpres[i] = lp_build_intrinsic_binary(builder, intrinsic, 670 nintr_vec_type, tmplo, tmphi); 671 if (ndst_vec_type != nintr_vec_type) { 672 tmpres[i] = LLVMBuildBitCast(builder, tmpres[i], ndst_vec_type, ""); 673 } 674 } 675 for (i = 0; i < num_split / 2; i++) { 676 tmplo = lp_build_extract_range(gallivm, 677 hi, i*nlen*2 + lo_off, nlen); 678 tmphi = lp_build_extract_range(gallivm, 679 hi, i*nlen*2 + hi_off, nlen); 680 tmpres[i+num_split/2] = lp_build_intrinsic_binary(builder, intrinsic, 681 nintr_vec_type, 682 tmplo, tmphi); 683 if (ndst_vec_type != nintr_vec_type) { 684 tmpres[i+num_split/2] = LLVMBuildBitCast(builder, tmpres[i+num_split/2], 685 ndst_vec_type, ""); 686 } 687 } 688 res = lp_build_concat(gallivm, tmpres, ndst_type, num_split); 689 } 690 return res; 691 } 692 } 693 694 /* generic shuffle */ 695 lo = LLVMBuildBitCast(builder, lo, dst_vec_type, ""); 696 hi = LLVMBuildBitCast(builder, hi, dst_vec_type, ""); 697 698 shuffle = lp_build_const_pack_shuffle(gallivm, dst_type.length); 699 700 res = LLVMBuildShuffleVector(builder, lo, hi, shuffle, ""); 701 702 return res; 703 } 704 705 706 /** 707 * Non-interleaved native pack. 708 * 709 * Similar to lp_build_pack2, but the ordering of values is not 710 * guaranteed, other than it will match lp_build_unpack2_native. 711 * 712 * In particular, with avx2, the lower and upper 128bits of the vectors will 713 * be packed independently, so that (with 32bit->16bit values) 714 * (LSB) (MSB) 715 * lo = l0 __ l1 __ l2 __ l3 __ l4 __ l5 __ l6 __ l7 __ 716 * hi = h0 __ h1 __ h2 __ h3 __ h4 __ h5 __ h6 __ h7 __ 717 * res = l0 l1 l2 l3 h0 h1 h2 h3 l4 l5 l6 l7 h4 h5 h6 h7 718 * 719 * This will only change the number of bits the values are represented, not the 720 * values themselves. 721 * 722 * It is assumed the values are already clamped into the destination type range. 723 * Values outside that range will produce undefined results. 724 */ 725 LLVMValueRef 726 lp_build_pack2_native(struct gallivm_state *gallivm, 727 struct lp_type src_type, 728 struct lp_type dst_type, 729 LLVMValueRef lo, 730 LLVMValueRef hi) 731 { 732 LLVMBuilderRef builder = gallivm->builder; 733 struct lp_type intr_type = dst_type; 734 const char *intrinsic = NULL; 735 736 assert(!src_type.floating); 737 assert(!dst_type.floating); 738 assert(src_type.width == dst_type.width * 2); 739 assert(src_type.length * 2 == dst_type.length); 740 741 /* At this point only have special case for avx2 */ 742 if (src_type.length * src_type.width == 256 && 743 util_cpu_caps.has_avx2) { 744 switch(src_type.width) { 745 case 32: 746 if (dst_type.sign) { 747 intrinsic = "llvm.x86.avx2.packssdw"; 748 } else { 749 intrinsic = "llvm.x86.avx2.packusdw"; 750 } 751 break; 752 case 16: 753 if (dst_type.sign) { 754 intrinsic = "llvm.x86.avx2.packsswb"; 755 } else { 756 intrinsic = "llvm.x86.avx2.packuswb"; 757 } 758 break; 759 } 760 } 761 if (intrinsic) { 762 LLVMTypeRef intr_vec_type = lp_build_vec_type(gallivm, intr_type); 763 return lp_build_intrinsic_binary(builder, intrinsic, intr_vec_type, 764 lo, hi); 765 } 766 else { 767 return lp_build_pack2(gallivm, src_type, dst_type, lo, hi); 768 } 769 } 770 771 /** 772 * Non-interleaved pack and saturate. 773 * 774 * Same as lp_build_pack2 but will saturate values so that they fit into the 775 * destination type. 776 */ 777 LLVMValueRef 778 lp_build_packs2(struct gallivm_state *gallivm, 779 struct lp_type src_type, 780 struct lp_type dst_type, 781 LLVMValueRef lo, 782 LLVMValueRef hi) 783 { 784 boolean clamp; 785 786 assert(!src_type.floating); 787 assert(!dst_type.floating); 788 assert(src_type.sign == dst_type.sign); 789 assert(src_type.width == dst_type.width * 2); 790 assert(src_type.length * 2 == dst_type.length); 791 792 clamp = TRUE; 793 794 /* All X86 SSE non-interleaved pack instructions take signed inputs and 795 * saturate them, so no need to clamp for those cases. */ 796 if(util_cpu_caps.has_sse2 && 797 src_type.width * src_type.length >= 128 && 798 src_type.sign && 799 (src_type.width == 32 || src_type.width == 16)) 800 clamp = FALSE; 801 802 if(clamp) { 803 struct lp_build_context bld; 804 unsigned dst_bits = dst_type.sign ? dst_type.width - 1 : dst_type.width; 805 LLVMValueRef dst_max = lp_build_const_int_vec(gallivm, src_type, 806 ((unsigned long long)1 << dst_bits) - 1); 807 lp_build_context_init(&bld, gallivm, src_type); 808 lo = lp_build_min(&bld, lo, dst_max); 809 hi = lp_build_min(&bld, hi, dst_max); 810 /* FIXME: What about lower bound? */ 811 } 812 813 return lp_build_pack2(gallivm, src_type, dst_type, lo, hi); 814 } 815 816 817 /** 818 * Truncate the bit width. 819 * 820 * TODO: Handle saturation consistently. 821 */ 822 LLVMValueRef 823 lp_build_pack(struct gallivm_state *gallivm, 824 struct lp_type src_type, 825 struct lp_type dst_type, 826 boolean clamped, 827 const LLVMValueRef *src, unsigned num_srcs) 828 { 829 LLVMValueRef (*pack2)(struct gallivm_state *gallivm, 830 struct lp_type src_type, 831 struct lp_type dst_type, 832 LLVMValueRef lo, 833 LLVMValueRef hi); 834 LLVMValueRef tmp[LP_MAX_VECTOR_LENGTH]; 835 unsigned i; 836 837 /* Register width must remain constant */ 838 assert(src_type.width * src_type.length == dst_type.width * dst_type.length); 839 840 /* We must not loose or gain channels. Only precision */ 841 assert(src_type.length * num_srcs == dst_type.length); 842 843 if(clamped) 844 pack2 = &lp_build_pack2; 845 else 846 pack2 = &lp_build_packs2; 847 848 for(i = 0; i < num_srcs; ++i) 849 tmp[i] = src[i]; 850 851 while(src_type.width > dst_type.width) { 852 struct lp_type tmp_type = src_type; 853 854 tmp_type.width /= 2; 855 tmp_type.length *= 2; 856 857 /* Take in consideration the sign changes only in the last step */ 858 if(tmp_type.width == dst_type.width) 859 tmp_type.sign = dst_type.sign; 860 861 num_srcs /= 2; 862 863 for(i = 0; i < num_srcs; ++i) 864 tmp[i] = pack2(gallivm, src_type, tmp_type, 865 tmp[2*i + 0], tmp[2*i + 1]); 866 867 src_type = tmp_type; 868 } 869 870 assert(num_srcs == 1); 871 872 return tmp[0]; 873 } 874 875 876 /** 877 * Truncate or expand the bitwidth. 878 * 879 * NOTE: Getting the right sign flags is crucial here, as we employ some 880 * intrinsics that do saturation. 881 */ 882 void 883 lp_build_resize(struct gallivm_state *gallivm, 884 struct lp_type src_type, 885 struct lp_type dst_type, 886 const LLVMValueRef *src, unsigned num_srcs, 887 LLVMValueRef *dst, unsigned num_dsts) 888 { 889 LLVMBuilderRef builder = gallivm->builder; 890 LLVMValueRef tmp[LP_MAX_VECTOR_LENGTH]; 891 unsigned i; 892 893 /* 894 * We don't support float <-> int conversion here. That must be done 895 * before/after calling this function. 896 */ 897 assert(src_type.floating == dst_type.floating); 898 899 /* 900 * We don't support double <-> float conversion yet, although it could be 901 * added with little effort. 902 */ 903 assert((!src_type.floating && !dst_type.floating) || 904 src_type.width == dst_type.width); 905 906 /* We must not loose or gain channels. Only precision */ 907 assert(src_type.length * num_srcs == dst_type.length * num_dsts); 908 909 assert(src_type.length <= LP_MAX_VECTOR_LENGTH); 910 assert(dst_type.length <= LP_MAX_VECTOR_LENGTH); 911 assert(num_srcs <= LP_MAX_VECTOR_LENGTH); 912 assert(num_dsts <= LP_MAX_VECTOR_LENGTH); 913 914 if (src_type.width > dst_type.width) { 915 /* 916 * Truncate bit width. 917 */ 918 919 /* Conversion must be M:1 */ 920 assert(num_dsts == 1); 921 922 if (src_type.width * src_type.length == dst_type.width * dst_type.length) { 923 /* 924 * Register width remains constant -- use vector packing intrinsics 925 */ 926 tmp[0] = lp_build_pack(gallivm, src_type, dst_type, TRUE, src, num_srcs); 927 } 928 else { 929 if (src_type.width / dst_type.width > num_srcs) { 930 /* 931 * First change src vectors size (with shuffle) so they have the 932 * same size as the destination vector, then pack normally. 933 * Note: cannot use cast/extract because llvm generates atrocious code. 934 */ 935 unsigned size_ratio = (src_type.width * src_type.length) / 936 (dst_type.length * dst_type.width); 937 unsigned new_length = src_type.length / size_ratio; 938 939 for (i = 0; i < size_ratio * num_srcs; i++) { 940 unsigned start_index = (i % size_ratio) * new_length; 941 tmp[i] = lp_build_extract_range(gallivm, src[i / size_ratio], 942 start_index, new_length); 943 } 944 num_srcs *= size_ratio; 945 src_type.length = new_length; 946 tmp[0] = lp_build_pack(gallivm, src_type, dst_type, TRUE, tmp, num_srcs); 947 } 948 else { 949 /* 950 * Truncate bit width but expand vector size - first pack 951 * then expand simply because this should be more AVX-friendly 952 * for the cases we probably hit. 953 */ 954 unsigned size_ratio = (dst_type.width * dst_type.length) / 955 (src_type.length * src_type.width); 956 unsigned num_pack_srcs = num_srcs / size_ratio; 957 dst_type.length = dst_type.length / size_ratio; 958 959 for (i = 0; i < size_ratio; i++) { 960 tmp[i] = lp_build_pack(gallivm, src_type, dst_type, TRUE, 961 &src[i*num_pack_srcs], num_pack_srcs); 962 } 963 tmp[0] = lp_build_concat(gallivm, tmp, dst_type, size_ratio); 964 } 965 } 966 } 967 else if (src_type.width < dst_type.width) { 968 /* 969 * Expand bit width. 970 */ 971 972 /* Conversion must be 1:N */ 973 assert(num_srcs == 1); 974 975 if (src_type.width * src_type.length == dst_type.width * dst_type.length) { 976 /* 977 * Register width remains constant -- use vector unpack intrinsics 978 */ 979 lp_build_unpack(gallivm, src_type, dst_type, src[0], tmp, num_dsts); 980 } 981 else { 982 /* 983 * Do it element-wise. 984 */ 985 assert(src_type.length * num_srcs == dst_type.length * num_dsts); 986 987 for (i = 0; i < num_dsts; i++) { 988 tmp[i] = lp_build_undef(gallivm, dst_type); 989 } 990 991 for (i = 0; i < src_type.length; ++i) { 992 unsigned j = i / dst_type.length; 993 LLVMValueRef srcindex = lp_build_const_int32(gallivm, i); 994 LLVMValueRef dstindex = lp_build_const_int32(gallivm, i % dst_type.length); 995 LLVMValueRef val = LLVMBuildExtractElement(builder, src[0], srcindex, ""); 996 997 if (src_type.sign && dst_type.sign) { 998 val = LLVMBuildSExt(builder, val, lp_build_elem_type(gallivm, dst_type), ""); 999 } else { 1000 val = LLVMBuildZExt(builder, val, lp_build_elem_type(gallivm, dst_type), ""); 1001 } 1002 tmp[j] = LLVMBuildInsertElement(builder, tmp[j], val, dstindex, ""); 1003 } 1004 } 1005 } 1006 else { 1007 /* 1008 * No-op 1009 */ 1010 1011 /* "Conversion" must be N:N */ 1012 assert(num_srcs == num_dsts); 1013 1014 for(i = 0; i < num_dsts; ++i) 1015 tmp[i] = src[i]; 1016 } 1017 1018 for(i = 0; i < num_dsts; ++i) 1019 dst[i] = tmp[i]; 1020 } 1021 1022 1023 /** 1024 * Expands src vector from src.length to dst_length 1025 */ 1026 LLVMValueRef 1027 lp_build_pad_vector(struct gallivm_state *gallivm, 1028 LLVMValueRef src, 1029 unsigned dst_length) 1030 { 1031 LLVMValueRef elems[LP_MAX_VECTOR_LENGTH]; 1032 LLVMValueRef undef; 1033 LLVMTypeRef type; 1034 unsigned i, src_length; 1035 1036 type = LLVMTypeOf(src); 1037 1038 if (LLVMGetTypeKind(type) != LLVMVectorTypeKind) { 1039 /* Can't use ShuffleVector on non-vector type */ 1040 undef = LLVMGetUndef(LLVMVectorType(type, dst_length)); 1041 return LLVMBuildInsertElement(gallivm->builder, undef, src, lp_build_const_int32(gallivm, 0), ""); 1042 } 1043 1044 undef = LLVMGetUndef(type); 1045 src_length = LLVMGetVectorSize(type); 1046 1047 assert(dst_length <= ARRAY_SIZE(elems)); 1048 assert(dst_length >= src_length); 1049 1050 if (src_length == dst_length) 1051 return src; 1052 1053 /* All elements from src vector */ 1054 for (i = 0; i < src_length; ++i) 1055 elems[i] = lp_build_const_int32(gallivm, i); 1056 1057 /* Undef fill remaining space */ 1058 for (i = src_length; i < dst_length; ++i) 1059 elems[i] = lp_build_const_int32(gallivm, src_length); 1060 1061 /* Combine the two vectors */ 1062 return LLVMBuildShuffleVector(gallivm->builder, src, undef, LLVMConstVector(elems, dst_length), ""); 1063 } 1064
