1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Copyright (c) 2010-2011, The Linux Foundation. All rights reserved. 4 */ 5 6 /* 7 * Description 8 * 9 * library function for memcpy where length bytes are copied from 10 * ptr_in to ptr_out. ptr_out is returned unchanged. 11 * Allows any combination of alignment on input and output pointers 12 * and length from 0 to 2^32-1 13 * 14 * Restrictions 15 * The arrays should not overlap, the program will produce undefined output 16 * if they do. 17 * For blocks less than 16 bytes a byte by byte copy is performed. For 18 * 8byte alignments, and length multiples, a dword copy is performed up to 19 * 96bytes 20 * History 21 * 22 * DJH 5/15/09 Initial version 1.0 23 * DJH 6/ 1/09 Version 1.1 modified ABI to inlcude R16-R19 24 * DJH 7/12/09 Version 1.2 optimized codesize down to 760 was 840 25 * DJH 10/14/09 Version 1.3 added special loop for aligned case, was 26 * overreading bloated codesize back up to 892 27 * DJH 4/20/10 Version 1.4 fixed Ldword_loop_epilog loop to prevent loads 28 * occurring if only 1 left outstanding, fixes bug 29 * # 3888, corrected for all alignments. Peeled off 30 * 1 32byte chunk from kernel loop and extended 8byte 31 * loop at end to solve all combinations and prevent 32 * over read. Fixed Ldword_loop_prolog to prevent 33 * overread for blocks less than 48bytes. Reduced 34 * codesize to 752 bytes 35 * DJH 4/21/10 version 1.5 1.4 fix broke code for input block ends not 36 * aligned to dword boundaries,underwriting by 1 37 * byte, added detection for this and fixed. A 38 * little bloat. 39 * DJH 4/23/10 version 1.6 corrected stack error, R20 was not being restored 40 * always, fixed the error of R20 being modified 41 * before it was being saved 42 * Natural c model 43 * =============== 44 * void * memcpy(char * ptr_out, char * ptr_in, int length) { 45 * int i; 46 * if(length) for(i=0; i < length; i++) { ptr_out[i] = ptr_in[i]; } 47 * return(ptr_out); 48 * } 49 * 50 * Optimized memcpy function 51 * ========================= 52 * void * memcpy(char * ptr_out, char * ptr_in, int len) { 53 * int i, prolog, kernel, epilog, mask; 54 * u8 offset; 55 * s64 data0, dataF8, data70; 56 * 57 * s64 * ptr8_in; 58 * s64 * ptr8_out; 59 * s32 * ptr4; 60 * s16 * ptr2; 61 * 62 * offset = ((int) ptr_in) & 7; 63 * ptr8_in = (s64 *) &ptr_in[-offset]; //read in the aligned pointers 64 * 65 * data70 = *ptr8_in++; 66 * dataF8 = *ptr8_in++; 67 * 68 * data0 = HEXAGON_P_valignb_PPp(dataF8, data70, offset); 69 * 70 * prolog = 32 - ((int) ptr_out); 71 * mask = 0x7fffffff >> HEXAGON_R_cl0_R(len); 72 * prolog = prolog & mask; 73 * kernel = len - prolog; 74 * epilog = kernel & 0x1F; 75 * kernel = kernel>>5; 76 * 77 * if (prolog & 1) { ptr_out[0] = (u8) data0; data0 >>= 8; ptr_out += 1;} 78 * ptr2 = (s16 *) &ptr_out[0]; 79 * if (prolog & 2) { ptr2[0] = (u16) data0; data0 >>= 16; ptr_out += 2;} 80 * ptr4 = (s32 *) &ptr_out[0]; 81 * if (prolog & 4) { ptr4[0] = (u32) data0; data0 >>= 32; ptr_out += 4;} 82 * 83 * offset = offset + (prolog & 7); 84 * if (offset >= 8) { 85 * data70 = dataF8; 86 * dataF8 = *ptr8_in++; 87 * } 88 * offset = offset & 0x7; 89 * 90 * prolog = prolog >> 3; 91 * if (prolog) for (i=0; i < prolog; i++) { 92 * data0 = HEXAGON_P_valignb_PPp(dataF8, data70, offset); 93 * ptr8_out = (s64 *) &ptr_out[0]; *ptr8_out = data0; ptr_out += 8; 94 * data70 = dataF8; 95 * dataF8 = *ptr8_in++; 96 * } 97 * if(kernel) { kernel -= 1; epilog += 32; } 98 * if(kernel) for(i=0; i < kernel; i++) { 99 * data0 = HEXAGON_P_valignb_PPp(dataF8, data70, offset); 100 * ptr8_out = (s64 *) &ptr_out[0]; *ptr8_out = data0; ptr_out += 8; 101 * data70 = *ptr8_in++; 102 * 103 * data0 = HEXAGON_P_valignb_PPp(data70, dataF8, offset); 104 * ptr8_out = (s64 *) &ptr_out[0]; *ptr8_out = data0; ptr_out += 8; 105 * dataF8 = *ptr8_in++; 106 * 107 * data0 = HEXAGON_P_valignb_PPp(dataF8, data70, offset); 108 * ptr8_out = (s64 *) &ptr_out[0]; *ptr8_out = data0; ptr_out += 8; 109 * data70 = *ptr8_in++; 110 * 111 * data0 = HEXAGON_P_valignb_PPp(data70, dataF8, offset); 112 * ptr8_out = (s64 *) &ptr_out[0]; *ptr8_out = data0; ptr_out += 8; 113 * dataF8 = *ptr8_in++; 114 * } 115 * epilogdws = epilog >> 3; 116 * if (epilogdws) for (i=0; i < epilogdws; i++) { 117 * data0 = HEXAGON_P_valignb_PPp(dataF8, data70, offset); 118 * ptr8_out = (s64 *) &ptr_out[0]; *ptr8_out = data0; ptr_out += 8; 119 * data70 = dataF8; 120 * dataF8 = *ptr8_in++; 121 * } 122 * data0 = HEXAGON_P_valignb_PPp(dataF8, data70, offset); 123 * 124 * ptr4 = (s32 *) &ptr_out[0]; 125 * if (epilog & 4) { ptr4[0] = (u32) data0; data0 >>= 32; ptr_out += 4;} 126 * ptr2 = (s16 *) &ptr_out[0]; 127 * if (epilog & 2) { ptr2[0] = (u16) data0; data0 >>= 16; ptr_out += 2;} 128 * if (epilog & 1) { *ptr_out++ = (u8) data0; } 129 * 130 * return(ptr_out - length); 131 * } 132 * 133 * Codesize : 784 bytes 134 */ 135 136 137 #define ptr_out R0 /* destination pounter */ 138 #define ptr_in R1 /* source pointer */ 139 #define len R2 /* length of copy in bytes */ 140 141 #define data70 R13:12 /* lo 8 bytes of non-aligned transfer */ 142 #define dataF8 R11:10 /* hi 8 bytes of non-aligned transfer */ 143 #define ldata0 R7:6 /* even 8 bytes chunks */ 144 #define ldata1 R25:24 /* odd 8 bytes chunks */ 145 #define data1 R7 /* lower 8 bytes of ldata1 */ 146 #define data0 R6 /* lower 8 bytes of ldata0 */ 147 148 #define ifbyte p0 /* if transfer has bytes in epilog/prolog */ 149 #define ifhword p0 /* if transfer has shorts in epilog/prolog */ 150 #define ifword p0 /* if transfer has words in epilog/prolog */ 151 #define noprolog p0 /* no prolog, xfer starts at 32byte */ 152 #define nokernel p1 /* no 32byte multiple block in the transfer */ 153 #define noepilog p0 /* no epilog, xfer ends on 32byte boundary */ 154 #define align p2 /* alignment of input rel to 8byte boundary */ 155 #define kernel1 p0 /* kernel count == 1 */ 156 157 #define dalign R25 /* rel alignment of input to output data */ 158 #define star3 R16 /* number bytes in prolog - dwords */ 159 #define rest R8 /* length - prolog bytes */ 160 #define back R7 /* nr bytes > dword boundary in src block */ 161 #define epilog R3 /* bytes in epilog */ 162 #define inc R15:14 /* inc kernel by -1 and defetch ptr by 32 */ 163 #define kernel R4 /* number of 32byte chunks in kernel */ 164 #define ptr_in_p_128 R5 /* pointer for prefetch of input data */ 165 #define mask R8 /* mask used to determine prolog size */ 166 #define shift R8 /* used to work a shifter to extract bytes */ 167 #define shift2 R5 /* in epilog to workshifter to extract bytes */ 168 #define prolog R15 /* bytes in prolog */ 169 #define epilogdws R15 /* number dwords in epilog */ 170 #define shiftb R14 /* used to extract bytes */ 171 #define offset R9 /* same as align in reg */ 172 #define ptr_out_p_32 R17 /* pointer to output dczero */ 173 #define align888 R14 /* if simple dword loop can be used */ 174 #define len8 R9 /* number of dwords in length */ 175 #define over R20 /* nr of bytes > last inp buf dword boundary */ 176 177 #define ptr_in_p_128kernel R5:4 /* packed fetch pointer & kernel cnt */ 178 179 .section .text 180 .p2align 4 181 .global memcpy 182 .type memcpy, @function 183 memcpy: 184 { 185 p2 = cmp.eq(len, #0); /* =0 */ 186 align888 = or(ptr_in, ptr_out); /* %8 < 97 */ 187 p0 = cmp.gtu(len, #23); /* %1, <24 */ 188 p1 = cmp.eq(ptr_in, ptr_out); /* attempt to overwrite self */ 189 } 190 { 191 p1 = or(p2, p1); 192 p3 = cmp.gtu(len, #95); /* %8 < 97 */ 193 align888 = or(align888, len); /* %8 < 97 */ 194 len8 = lsr(len, #3); /* %8 < 97 */ 195 } 196 { 197 dcfetch(ptr_in); /* zero/ptrin=ptrout causes fetch */ 198 p2 = bitsclr(align888, #7); /* %8 < 97 */ 199 if(p1) jumpr r31; /* =0 */ 200 } 201 { 202 p2 = and(p2,!p3); /* %8 < 97 */ 203 if (p2.new) len = add(len, #-8); /* %8 < 97 */ 204 if (p2.new) jump:NT .Ldwordaligned; /* %8 < 97 */ 205 } 206 { 207 if(!p0) jump .Lbytes23orless; /* %1, <24 */ 208 mask.l = #LO(0x7fffffff); 209 /* all bytes before line multiples of data */ 210 prolog = sub(#0, ptr_out); 211 } 212 { 213 /* save r31 on stack, decrement sp by 16 */ 214 allocframe(#24); 215 mask.h = #HI(0x7fffffff); 216 ptr_in_p_128 = add(ptr_in, #32); 217 back = cl0(len); 218 } 219 { 220 memd(sp+#0) = R17:16; /* save r16,r17 on stack6 */ 221 r31.l = #LO(.Lmemcpy_return); /* set up final return pointer */ 222 prolog &= lsr(mask, back); 223 offset = and(ptr_in, #7); 224 } 225 { 226 memd(sp+#8) = R25:24; /* save r25,r24 on stack */ 227 dalign = sub(ptr_out, ptr_in); 228 r31.h = #HI(.Lmemcpy_return); /* set up final return pointer */ 229 } 230 { 231 /* see if there if input buffer end if aligned */ 232 over = add(len, ptr_in); 233 back = add(len, offset); 234 memd(sp+#16) = R21:20; /* save r20,r21 on stack */ 235 } 236 { 237 noprolog = bitsclr(prolog, #7); 238 prolog = and(prolog, #31); 239 dcfetch(ptr_in_p_128); 240 ptr_in_p_128 = add(ptr_in_p_128, #32); 241 } 242 { 243 kernel = sub(len, prolog); 244 shift = asl(prolog, #3); 245 star3 = and(prolog, #7); 246 ptr_in = and(ptr_in, #-8); 247 } 248 { 249 prolog = lsr(prolog, #3); 250 epilog = and(kernel, #31); 251 ptr_out_p_32 = add(ptr_out, prolog); 252 over = and(over, #7); 253 } 254 { 255 p3 = cmp.gtu(back, #8); 256 kernel = lsr(kernel, #5); 257 dcfetch(ptr_in_p_128); 258 ptr_in_p_128 = add(ptr_in_p_128, #32); 259 } 260 { 261 p1 = cmp.eq(prolog, #0); 262 if(!p1.new) prolog = add(prolog, #1); 263 dcfetch(ptr_in_p_128); /* reserve the line 64bytes on */ 264 ptr_in_p_128 = add(ptr_in_p_128, #32); 265 } 266 { 267 nokernel = cmp.eq(kernel,#0); 268 dcfetch(ptr_in_p_128); /* reserve the line 64bytes on */ 269 ptr_in_p_128 = add(ptr_in_p_128, #32); 270 shiftb = and(shift, #8); 271 } 272 { 273 dcfetch(ptr_in_p_128); /* reserve the line 64bytes on */ 274 ptr_in_p_128 = add(ptr_in_p_128, #32); 275 if(nokernel) jump .Lskip64; 276 p2 = cmp.eq(kernel, #1); /* skip ovr if kernel == 0 */ 277 } 278 { 279 dczeroa(ptr_out_p_32); 280 /* don't advance pointer */ 281 if(!p2) ptr_out_p_32 = add(ptr_out_p_32, #32); 282 } 283 { 284 dalign = and(dalign, #31); 285 dczeroa(ptr_out_p_32); 286 } 287 .Lskip64: 288 { 289 data70 = memd(ptr_in++#16); 290 if(p3) dataF8 = memd(ptr_in+#8); 291 if(noprolog) jump .Lnoprolog32; 292 align = offset; 293 } 294 /* upto initial 7 bytes */ 295 { 296 ldata0 = valignb(dataF8, data70, align); 297 ifbyte = tstbit(shift,#3); 298 offset = add(offset, star3); 299 } 300 { 301 if(ifbyte) memb(ptr_out++#1) = data0; 302 ldata0 = lsr(ldata0, shiftb); 303 shiftb = and(shift, #16); 304 ifhword = tstbit(shift,#4); 305 } 306 { 307 if(ifhword) memh(ptr_out++#2) = data0; 308 ldata0 = lsr(ldata0, shiftb); 309 ifword = tstbit(shift,#5); 310 p2 = cmp.gtu(offset, #7); 311 } 312 { 313 if(ifword) memw(ptr_out++#4) = data0; 314 if(p2) data70 = dataF8; 315 if(p2) dataF8 = memd(ptr_in++#8); /* another 8 bytes */ 316 align = offset; 317 } 318 .Lnoprolog32: 319 { 320 p3 = sp1loop0(.Ldword_loop_prolog, prolog) 321 rest = sub(len, star3); /* whats left after the loop */ 322 p0 = cmp.gt(over, #0); 323 } 324 if(p0) rest = add(rest, #16); 325 .Ldword_loop_prolog: 326 { 327 if(p3) memd(ptr_out++#8) = ldata0; 328 ldata0 = valignb(dataF8, data70, align); 329 p0 = cmp.gt(rest, #16); 330 } 331 { 332 data70 = dataF8; 333 if(p0) dataF8 = memd(ptr_in++#8); 334 rest = add(rest, #-8); 335 }:endloop0 336 .Lkernel: 337 { 338 /* kernel is at least 32bytes */ 339 p3 = cmp.gtu(kernel, #0); 340 /* last itn. remove edge effects */ 341 if(p3.new) kernel = add(kernel, #-1); 342 /* dealt with in last dword loop */ 343 if(p3.new) epilog = add(epilog, #32); 344 } 345 { 346 nokernel = cmp.eq(kernel, #0); /* after adjustment, recheck */ 347 if(nokernel.new) jump:NT .Lepilog; /* likely not taken */ 348 inc = combine(#32, #-1); 349 p3 = cmp.gtu(dalign, #24); 350 } 351 { 352 if(p3) jump .Lodd_alignment; 353 } 354 { 355 loop0(.Loword_loop_25to31, kernel); 356 kernel1 = cmp.gtu(kernel, #1); 357 rest = kernel; 358 } 359 .falign 360 .Loword_loop_25to31: 361 { 362 dcfetch(ptr_in_p_128); /* prefetch 4 lines ahead */ 363 if(kernel1) ptr_out_p_32 = add(ptr_out_p_32, #32); 364 } 365 { 366 dczeroa(ptr_out_p_32); /* reserve the next 32bytes in cache */ 367 p3 = cmp.eq(kernel, rest); 368 } 369 { 370 /* kernel -= 1 */ 371 ptr_in_p_128kernel = vaddw(ptr_in_p_128kernel, inc); 372 /* kill write on first iteration */ 373 if(!p3) memd(ptr_out++#8) = ldata1; 374 ldata1 = valignb(dataF8, data70, align); 375 data70 = memd(ptr_in++#8); 376 } 377 { 378 memd(ptr_out++#8) = ldata0; 379 ldata0 = valignb(data70, dataF8, align); 380 dataF8 = memd(ptr_in++#8); 381 } 382 { 383 memd(ptr_out++#8) = ldata1; 384 ldata1 = valignb(dataF8, data70, align); 385 data70 = memd(ptr_in++#8); 386 } 387 { 388 memd(ptr_out++#8) = ldata0; 389 ldata0 = valignb(data70, dataF8, align); 390 dataF8 = memd(ptr_in++#8); 391 kernel1 = cmp.gtu(kernel, #1); 392 }:endloop0 393 { 394 memd(ptr_out++#8) = ldata1; 395 jump .Lepilog; 396 } 397 .Lodd_alignment: 398 { 399 loop0(.Loword_loop_00to24, kernel); 400 kernel1 = cmp.gtu(kernel, #1); 401 rest = add(kernel, #-1); 402 } 403 .falign 404 .Loword_loop_00to24: 405 { 406 dcfetch(ptr_in_p_128); /* prefetch 4 lines ahead */ 407 ptr_in_p_128kernel = vaddw(ptr_in_p_128kernel, inc); 408 if(kernel1) ptr_out_p_32 = add(ptr_out_p_32, #32); 409 } 410 { 411 dczeroa(ptr_out_p_32); /* reserve the next 32bytes in cache */ 412 } 413 { 414 memd(ptr_out++#8) = ldata0; 415 ldata0 = valignb(dataF8, data70, align); 416 data70 = memd(ptr_in++#8); 417 } 418 { 419 memd(ptr_out++#8) = ldata0; 420 ldata0 = valignb(data70, dataF8, align); 421 dataF8 = memd(ptr_in++#8); 422 } 423 { 424 memd(ptr_out++#8) = ldata0; 425 ldata0 = valignb(dataF8, data70, align); 426 data70 = memd(ptr_in++#8); 427 } 428 { 429 memd(ptr_out++#8) = ldata0; 430 ldata0 = valignb(data70, dataF8, align); 431 dataF8 = memd(ptr_in++#8); 432 kernel1 = cmp.gtu(kernel, #1); 433 }:endloop0 434 .Lepilog: 435 { 436 noepilog = cmp.eq(epilog,#0); 437 epilogdws = lsr(epilog, #3); 438 kernel = and(epilog, #7); 439 } 440 { 441 if(noepilog) jumpr r31; 442 if(noepilog) ptr_out = sub(ptr_out, len); 443 p3 = cmp.eq(epilogdws, #0); 444 shift2 = asl(epilog, #3); 445 } 446 { 447 shiftb = and(shift2, #32); 448 ifword = tstbit(epilog,#2); 449 if(p3) jump .Lepilog60; 450 if(!p3) epilog = add(epilog, #-16); 451 } 452 { 453 loop0(.Ldword_loop_epilog, epilogdws); 454 /* stop criteria is lsbs unless = 0 then its 8 */ 455 p3 = cmp.eq(kernel, #0); 456 if(p3.new) kernel= #8; 457 p1 = cmp.gt(over, #0); 458 } 459 /* if not aligned to end of buffer execute 1 more iteration */ 460 if(p1) kernel= #0; 461 .Ldword_loop_epilog: 462 { 463 memd(ptr_out++#8) = ldata0; 464 ldata0 = valignb(dataF8, data70, align); 465 p3 = cmp.gt(epilog, kernel); 466 } 467 { 468 data70 = dataF8; 469 if(p3) dataF8 = memd(ptr_in++#8); 470 epilog = add(epilog, #-8); 471 }:endloop0 472 /* copy last 7 bytes */ 473 .Lepilog60: 474 { 475 if(ifword) memw(ptr_out++#4) = data0; 476 ldata0 = lsr(ldata0, shiftb); 477 ifhword = tstbit(epilog,#1); 478 shiftb = and(shift2, #16); 479 } 480 { 481 if(ifhword) memh(ptr_out++#2) = data0; 482 ldata0 = lsr(ldata0, shiftb); 483 ifbyte = tstbit(epilog,#0); 484 if(ifbyte.new) len = add(len, #-1); 485 } 486 { 487 if(ifbyte) memb(ptr_out) = data0; 488 ptr_out = sub(ptr_out, len); /* return dest pointer */ 489 jumpr r31; 490 } 491 /* do byte copy for small n */ 492 .Lbytes23orless: 493 { 494 p3 = sp1loop0(.Lbyte_copy, len); 495 len = add(len, #-1); 496 } 497 .Lbyte_copy: 498 { 499 data0 = memb(ptr_in++#1); 500 if(p3) memb(ptr_out++#1) = data0; 501 }:endloop0 502 { 503 memb(ptr_out) = data0; 504 ptr_out = sub(ptr_out, len); 505 jumpr r31; 506 } 507 /* do dword copies for aligned in, out and length */ 508 .Ldwordaligned: 509 { 510 p3 = sp1loop0(.Ldword_copy, len8); 511 } 512 .Ldword_copy: 513 { 514 if(p3) memd(ptr_out++#8) = ldata0; 515 ldata0 = memd(ptr_in++#8); 516 }:endloop0 517 { 518 memd(ptr_out) = ldata0; 519 ptr_out = sub(ptr_out, len); 520 jumpr r31; /* return to function caller */ 521 } 522 .Lmemcpy_return: 523 r21:20 = memd(sp+#16); /* restore r20+r21 */ 524 { 525 r25:24 = memd(sp+#8); /* restore r24+r25 */ 526 r17:16 = memd(sp+#0); /* restore r16+r17 */ 527 } 528 deallocframe; /* restore r31 and incrment stack by 16 */ 529 jumpr r31 530