/* Optimized version of the memccpy() function. This file is part of the GNU C Library. Copyright (C) 2000, 2001, 2003 Free Software Foundation, Inc. Contributed by Dan Pop <Dan.Pop@cern.ch>. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */ /* Return: a pointer to the next byte after char in dest or NULL Inputs: in0: dest in1: src in2: char in3: byte count This implementation assumes little endian mode (UM.be = 0). This implementation assumes that it is safe to do read ahead in the src block, without getting beyond its limit. */ #include "sysdep.h" #undef ret #define OP_T_THRES 16 #define OPSIZ 8 #define saved_pr r17 #define saved_lc r18 #define dest r19 #define src r20 #define len r21 #define asrc r22 #define tmp r23 #define char r24 #define charx8 r25 #define saved_ec r26 #define sh2 r28 #define sh1 r29 #define loopcnt r30 #define value r31 #ifdef GAS_ALIGN_BREAKS_UNWIND_INFO /* Manually force proper loop-alignment. Note: be sure to double-check the code-layout after making any changes to this routine! */ # define ALIGN(n) { nop 0 } #else # define ALIGN(n) .align n #endif ENTRY(memccpy) .prologue alloc r2 = ar.pfs, 4, 40 - 4, 0, 40 #include "softpipe.h" .rotr r[MEMLAT + 7], tmp1[4], tmp2[4], val[4], tmp3[2], pos0[2] .rotp p[MEMLAT + 6 + 1] mov ret0 = r0 // return NULL if no match .save pr, saved_pr mov saved_pr = pr // save the predicate registers mov dest = in0 // dest .save ar.lc, saved_lc mov saved_lc = ar.lc // save the loop counter mov saved_ec = ar.ec // save the loop counter .body mov src = in1 // src extr.u char = in2, 0, 8 // char mov len = in3 // len sub tmp = r0, in0 // tmp = -dest cmp.ne p7, p0 = r0, r0 // clear p7 ;; and loopcnt = 7, tmp // loopcnt = -dest % 8 cmp.ge p6, p0 = OP_T_THRES, len // is len <= OP_T_THRES mov ar.ec = 0 // ec not guaranteed zero on entry (p6) br.cond.spnt .cpyfew // copy byte by byte ;; cmp.eq p6, p0 = loopcnt, r0 mux1 charx8 = char, @brcst (p6) br.cond.sptk .dest_aligned sub len = len, loopcnt // len -= -dest % 8 adds loopcnt = -1, loopcnt // --loopcnt ;; mov ar.lc = loopcnt .l1: // copy -dest % 8 bytes ld1 value = [src], 1 // value = *src++ ;; st1 [dest] = value, 1 // *dest++ = value cmp.eq p6, p0 = value, char (p6) br.cond.spnt .foundit br.cloop.dptk .l1 .dest_aligned: and sh1 = 7, src // sh1 = src % 8 and tmp = -8, len // tmp = len & -OPSIZ and asrc = -8, src // asrc = src & -OPSIZ -- align src shr.u loopcnt = len, 3 // loopcnt = len / 8 and len = 7, len ;; // len = len % 8 shl sh1 = sh1, 3 // sh1 = 8 * (src % 8) adds loopcnt = -1, loopcnt // --loopcnt mov pr.rot = 1 << 16 ;; // set rotating predicates sub sh2 = 64, sh1 // sh2 = 64 - sh1 mov ar.lc = loopcnt // set LC cmp.eq p6, p0 = sh1, r0 // is the src aligned? (p6) br.cond.sptk .src_aligned ;; add src = src, tmp // src += len & -OPSIZ mov ar.ec = MEMLAT + 6 + 1 // six more passes needed ld8 r[1] = [asrc], 8 // r[1] = w0 cmp.ne p6, p0 = r0, r0 ;; // clear p6 ALIGN(32) .l2: (p[0]) ld8.s r[0] = [asrc], 8 // r[0] = w1 (p[MEMLAT]) shr.u tmp1[0] = r[1 + MEMLAT], sh1 // tmp1 = w0 >> sh1 (p[MEMLAT]) shl tmp2[0] = r[0 + MEMLAT], sh2 // tmp2 = w1 << sh2 (p[MEMLAT+4]) xor tmp3[0] = val[1], charx8 (p[MEMLAT+5]) czx1.r pos0[0] = tmp3[1] (p[MEMLAT+6]) chk.s r[6 + MEMLAT], .recovery1 // our data isn't // valid - rollback! (p[MEMLAT+6]) cmp.ne p6, p0 = 8, pos0[1] (p6) br.cond.spnt .gotit (p[MEMLAT+6]) st8 [dest] = val[3], 8 // store val to dest (p[MEMLAT+3]) or val[0] = tmp1[3], tmp2[3] // val = tmp1 | tmp2 br.ctop.sptk .l2 br.cond.sptk .cpyfew .src_aligned: cmp.ne p6, p0 = r0, r0 // clear p6 mov ar.ec = MEMLAT + 2 + 1 ;; // set EC .l3: (p[0]) ld8.s r[0] = [src], 8 (p[MEMLAT]) xor tmp3[0] = r[MEMLAT], charx8 (p[MEMLAT+1]) czx1.r pos0[0] = tmp3[1] (p[MEMLAT+2]) cmp.ne p7, p0 = 8, pos0[1] (p[MEMLAT+2]) chk.s r[MEMLAT+2], .recovery2 (p7) br.cond.spnt .gotit .back2: (p[MEMLAT+2]) st8 [dest] = r[MEMLAT+2], 8 br.ctop.dptk .l3 .cpyfew: cmp.eq p6, p0 = len, r0 // is len == 0 ? adds len = -1, len // --len; (p6) br.cond.spnt .restore_and_exit ;; mov ar.lc = len .l4: ld1 value = [src], 1 ;; st1 [dest] = value, 1 cmp.eq p6, p0 = value, char (p6) br.cond.spnt .foundit br.cloop.dptk .l4 ;; .foundit: (p6) mov ret0 = dest .restore_and_exit: mov pr = saved_pr, -1 // restore the predicate registers mov ar.lc = saved_lc // restore the loop counter mov ar.ec = saved_ec ;; // restore the epilog counter br.ret.sptk.many b0 .gotit: .pred.rel "mutex" p6, p7 (p6) mov value = val[3] // if coming from l2 (p7) mov value = r[MEMLAT+2] // if coming from l3 mov ar.lc = pos0[1] ;; .l5: extr.u tmp = value, 0, 8 ;; st1 [dest] = tmp, 1 shr.u value = value, 8 br.cloop.sptk .l5 ;; mov ret0 = dest mov pr = saved_pr, -1 mov ar.lc = saved_lc br.ret.sptk.many b0 .recovery1: adds src = -(MEMLAT + 6 + 1) * 8, asrc mov loopcnt = ar.lc mov tmp = ar.ec ;; sub sh1 = (MEMLAT + 6 + 1), tmp shr.u sh2 = sh2, 3 ;; shl loopcnt = loopcnt, 3 sub src = src, sh2 shl sh1 = sh1, 3 shl tmp = tmp, 3 ;; add len = len, loopcnt add src = sh1, src ;; add len = tmp, len .back1: br.cond.sptk .cpyfew .recovery2: add tmp = -(MEMLAT + 3) * 8, src (p7) br.cond.spnt .gotit ;; ld8 r[MEMLAT+2] = [tmp] ;; xor pos0[1] = r[MEMLAT+2], charx8 ;; czx1.r pos0[1] = pos0[1] ;; cmp.ne p7, p6 = 8, pos0[1] (p7) br.cond.spnt .gotit br.cond.sptk .back2 END(memccpy)