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author | Adhemerval Zanella <adhemerval.zanella@linaro.org> | 2022-02-10 11:31:03 -0300 |
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committer | Adhemerval Zanella <adhemerval.zanella@linaro.org> | 2022-02-23 14:18:17 -0300 |
commit | c0d215f162049e7ab8e86e9d2d76c87e41a55ebd (patch) | |
tree | 9dc3e85c6061f9fd4b78acf4a33f7c6cb2df2661 | |
parent | f883dbaf1fba5b870331ce980fe2176242bea6f2 (diff) | |
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ia64: Remove bzero optimization
The symbol is not present current POSIX specification and compiler
already generates memset call. The arch specific implementation
is just to avoid the __bzero symbol creation (which ia64 abi does
not export).
-rw-r--r-- | string/bzero.c | 4 | ||||
-rw-r--r-- | sysdeps/ia64/bzero.S | 312 | ||||
-rw-r--r-- | sysdeps/ia64/bzero.c | 3 |
3 files changed, 5 insertions, 314 deletions
diff --git a/string/bzero.c b/string/bzero.c index eb2af49e9e..d8b79df1c7 100644 --- a/string/bzero.c +++ b/string/bzero.c @@ -17,12 +17,12 @@ #include <string.h> -#undef __bzero - /* Set N bytes of S to 0. */ void __bzero (void *s, size_t len) { memset (s, '\0', len); } +#ifndef __bzero weak_alias (__bzero, bzero) +#endif diff --git a/sysdeps/ia64/bzero.S b/sysdeps/ia64/bzero.S deleted file mode 100644 index cd01abb436..0000000000 --- a/sysdeps/ia64/bzero.S +++ /dev/null @@ -1,312 +0,0 @@ -/* Optimized version of the standard bzero() function. - This file is part of the GNU C Library. - Copyright (C) 2000-2022 Free Software Foundation, Inc. - - 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, see - <https://www.gnu.org/licenses/>. */ - -/* Return: dest - - Inputs: - in0: dest - in1: count - - The algorithm is fairly straightforward: set byte by byte until we - we get to a 16B-aligned address, then loop on 128 B chunks using an - early store as prefetching, then loop on 32B chucks, then clear remaining - words, finally clear remaining bytes. - Since a stf.spill f0 can store 16B in one go, we use this instruction - to get peak speed. */ - -#include <sysdep.h> -#undef ret - -#define dest in0 -#define cnt in1 - -#define tmp r31 -#define save_lc r30 -#define ptr0 r29 -#define ptr1 r28 -#define ptr2 r27 -#define ptr3 r26 -#define ptr9 r24 -#define loopcnt r23 -#define linecnt r22 -#define bytecnt r21 - -// This routine uses only scratch predicate registers (p6 - p15) -#define p_scr p6 // default register for same-cycle branches -#define p_unalgn p9 -#define p_y p11 -#define p_n p12 -#define p_yy p13 -#define p_nn p14 - -#define movi0 mov - -#define MIN1 15 -#define MIN1P1HALF 8 -#define LINE_SIZE 128 -#define LSIZE_SH 7 // shift amount -#define PREF_AHEAD 8 - -#define USE_FLP -#if defined(USE_INT) -#define store st8 -#define myval r0 -#elif defined(USE_FLP) -#define store stf8 -#define myval f0 -#endif - -.align 64 -ENTRY(bzero) -{ .mmi - .prologue - alloc tmp = ar.pfs, 2, 0, 0, 0 - lfetch.nt1 [dest] - .save ar.lc, save_lc - movi0 save_lc = ar.lc -} { .mmi - .body - mov ret0 = dest // return value - nop.m 0 - cmp.eq p_scr, p0 = cnt, r0 -;; } -{ .mmi - and ptr2 = -(MIN1+1), dest // aligned address - and tmp = MIN1, dest // prepare to check for alignment - tbit.nz p_y, p_n = dest, 0 // Do we have an odd address? (M_B_U) -} { .mib - mov ptr1 = dest - nop.i 0 -(p_scr) br.ret.dpnt.many rp // return immediately if count = 0 -;; } -{ .mib - cmp.ne p_unalgn, p0 = tmp, r0 -} { .mib // NB: # of bytes to move is 1 - sub bytecnt = (MIN1+1), tmp // higher than loopcnt - cmp.gt p_scr, p0 = 16, cnt // is it a minimalistic task? -(p_scr) br.cond.dptk.many .move_bytes_unaligned // go move just a few (M_B_U) -;; } -{ .mmi -(p_unalgn) add ptr1 = (MIN1+1), ptr2 // after alignment -(p_unalgn) add ptr2 = MIN1P1HALF, ptr2 // after alignment -(p_unalgn) tbit.nz.unc p_y, p_n = bytecnt, 3 // should we do a st8 ? -;; } -{ .mib -(p_y) add cnt = -8, cnt -(p_unalgn) tbit.nz.unc p_yy, p_nn = bytecnt, 2 // should we do a st4 ? -} { .mib -(p_y) st8 [ptr2] = r0,-4 -(p_n) add ptr2 = 4, ptr2 -;; } -{ .mib -(p_yy) add cnt = -4, cnt -(p_unalgn) tbit.nz.unc p_y, p_n = bytecnt, 1 // should we do a st2 ? -} { .mib -(p_yy) st4 [ptr2] = r0,-2 -(p_nn) add ptr2 = 2, ptr2 -;; } -{ .mmi - mov tmp = LINE_SIZE+1 // for compare -(p_y) add cnt = -2, cnt -(p_unalgn) tbit.nz.unc p_yy, p_nn = bytecnt, 0 // should we do a st1 ? -} { .mmi - nop.m 0 -(p_y) st2 [ptr2] = r0,-1 -(p_n) add ptr2 = 1, ptr2 -;; } - -{ .mmi -(p_yy) st1 [ptr2] = r0 - cmp.gt p_scr, p0 = tmp, cnt // is it a minimalistic task? -} { .mbb -(p_yy) add cnt = -1, cnt -(p_scr) br.cond.dpnt.many .fraction_of_line // go move just a few -;; } -{ .mib - nop.m 0 - shr.u linecnt = cnt, LSIZE_SH - nop.b 0 -;; } - - .align 32 -.l1b: // ------------------// L1B: store ahead into cache lines; fill later -{ .mmi - and tmp = -(LINE_SIZE), cnt // compute end of range - mov ptr9 = ptr1 // used for prefetching - and cnt = (LINE_SIZE-1), cnt // remainder -} { .mmi - mov loopcnt = PREF_AHEAD-1 // default prefetch loop - cmp.gt p_scr, p0 = PREF_AHEAD, linecnt // check against actual value -;; } -{ .mmi -(p_scr) add loopcnt = -1, linecnt - add ptr2 = 16, ptr1 // start of stores (beyond prefetch stores) - add ptr1 = tmp, ptr1 // first address beyond total range -;; } -{ .mmi - add tmp = -1, linecnt // next loop count - movi0 ar.lc = loopcnt -;; } -.pref_l1b: -{ .mib - stf.spill [ptr9] = f0, 128 // Do stores one cache line apart - nop.i 0 - br.cloop.dptk.few .pref_l1b -;; } -{ .mmi - add ptr0 = 16, ptr2 // Two stores in parallel - movi0 ar.lc = tmp -;; } -.l1bx: - { .mmi - stf.spill [ptr2] = f0, 32 - stf.spill [ptr0] = f0, 32 - ;; } - { .mmi - stf.spill [ptr2] = f0, 32 - stf.spill [ptr0] = f0, 32 - ;; } - { .mmi - stf.spill [ptr2] = f0, 32 - stf.spill [ptr0] = f0, 64 - cmp.lt p_scr, p0 = ptr9, ptr1 // do we need more prefetching? - ;; } -{ .mmb - stf.spill [ptr2] = f0, 32 -(p_scr) stf.spill [ptr9] = f0, 128 - br.cloop.dptk.few .l1bx -;; } -{ .mib - cmp.gt p_scr, p0 = 8, cnt // just a few bytes left ? -(p_scr) br.cond.dpnt.many .move_bytes_from_alignment -;; } - -.fraction_of_line: -{ .mib - add ptr2 = 16, ptr1 - shr.u loopcnt = cnt, 5 // loopcnt = cnt / 32 -;; } -{ .mib - cmp.eq p_scr, p0 = loopcnt, r0 - add loopcnt = -1, loopcnt -(p_scr) br.cond.dpnt.many .store_words -;; } -{ .mib - and cnt = 0x1f, cnt // compute the remaining cnt - movi0 ar.lc = loopcnt -;; } - .align 32 -.l2: // -----------------------------// L2A: store 32B in 2 cycles -{ .mmb - store [ptr1] = myval, 8 - store [ptr2] = myval, 8 -;; } { .mmb - store [ptr1] = myval, 24 - store [ptr2] = myval, 24 - br.cloop.dptk.many .l2 -;; } -.store_words: -{ .mib - cmp.gt p_scr, p0 = 8, cnt // just a few bytes left ? -(p_scr) br.cond.dpnt.many .move_bytes_from_alignment // Branch -;; } - -{ .mmi - store [ptr1] = myval, 8 // store - cmp.le p_y, p_n = 16, cnt // - add cnt = -8, cnt // subtract -;; } -{ .mmi -(p_y) store [ptr1] = myval, 8 // store -(p_y) cmp.le.unc p_yy, p_nn = 16, cnt -(p_y) add cnt = -8, cnt // subtract -;; } -{ .mmi // store -(p_yy) store [ptr1] = myval, 8 -(p_yy) add cnt = -8, cnt // subtract -;; } - -.move_bytes_from_alignment: -{ .mib - cmp.eq p_scr, p0 = cnt, r0 - tbit.nz.unc p_y, p0 = cnt, 2 // should we terminate with a st4 ? -(p_scr) br.cond.dpnt.few .restore_and_exit -;; } -{ .mib -(p_y) st4 [ptr1] = r0,4 - tbit.nz.unc p_yy, p0 = cnt, 1 // should we terminate with a st2 ? -;; } -{ .mib -(p_yy) st2 [ptr1] = r0,2 - tbit.nz.unc p_y, p0 = cnt, 0 // should we terminate with a st1 ? -;; } - -{ .mib -(p_y) st1 [ptr1] = r0 -;; } -.restore_and_exit: -{ .mib - nop.m 0 - movi0 ar.lc = save_lc - br.ret.sptk.many rp -;; } - -.move_bytes_unaligned: -{ .mmi - .pred.rel "mutex",p_y, p_n - .pred.rel "mutex",p_yy, p_nn -(p_n) cmp.le p_yy, p_nn = 4, cnt -(p_y) cmp.le p_yy, p_nn = 5, cnt -(p_n) add ptr2 = 2, ptr1 -} { .mmi -(p_y) add ptr2 = 3, ptr1 -(p_y) st1 [ptr1] = r0, 1 // fill 1 (odd-aligned) byte -(p_y) add cnt = -1, cnt // [15, 14 (or less) left] -;; } -{ .mmi -(p_yy) cmp.le.unc p_y, p0 = 8, cnt - add ptr3 = ptr1, cnt // prepare last store - movi0 ar.lc = save_lc -} { .mmi -(p_yy) st2 [ptr1] = r0, 4 // fill 2 (aligned) bytes -(p_yy) st2 [ptr2] = r0, 4 // fill 2 (aligned) bytes -(p_yy) add cnt = -4, cnt // [11, 10 (o less) left] -;; } -{ .mmi -(p_y) cmp.le.unc p_yy, p0 = 8, cnt - add ptr3 = -1, ptr3 // last store - tbit.nz p_scr, p0 = cnt, 1 // will there be a st2 at the end ? -} { .mmi -(p_y) st2 [ptr1] = r0, 4 // fill 2 (aligned) bytes -(p_y) st2 [ptr2] = r0, 4 // fill 2 (aligned) bytes -(p_y) add cnt = -4, cnt // [7, 6 (or less) left] -;; } -{ .mmi -(p_yy) st2 [ptr1] = r0, 4 // fill 2 (aligned) bytes -(p_yy) st2 [ptr2] = r0, 4 // fill 2 (aligned) bytes - // [3, 2 (or less) left] - tbit.nz p_y, p0 = cnt, 0 // will there be a st1 at the end ? -} { .mmi -(p_yy) add cnt = -4, cnt -;; } -{ .mmb -(p_scr) st2 [ptr1] = r0 // fill 2 (aligned) bytes -(p_y) st1 [ptr3] = r0 // fill last byte (using ptr3) - br.ret.sptk.many rp -;; } -END(bzero) diff --git a/sysdeps/ia64/bzero.c b/sysdeps/ia64/bzero.c new file mode 100644 index 0000000000..79771f3e91 --- /dev/null +++ b/sysdeps/ia64/bzero.c @@ -0,0 +1,3 @@ +/* ia64 does not export __bzero symbol. */ +#define __bzero bzero +#include <string/bzero.c> |