glibc/sysdeps/ia64/strcpy.S

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/* Optimized version of the standard strcpy() function.
This file is part of the GNU C Library.
Copyright (C) 2000-2020 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, see
Prefer https to http for gnu.org and fsf.org URLs Also, change sources.redhat.com to sourceware.org. This patch was automatically generated by running the following shell script, which uses GNU sed, and which avoids modifying files imported from upstream: sed -ri ' s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g ' \ $(find $(git ls-files) -prune -type f \ ! -name '*.po' \ ! -name 'ChangeLog*' \ ! -path COPYING ! -path COPYING.LIB \ ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \ ! -path manual/texinfo.tex ! -path scripts/config.guess \ ! -path scripts/config.sub ! -path scripts/install-sh \ ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \ ! -path INSTALL ! -path locale/programs/charmap-kw.h \ ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \ ! '(' -name configure \ -execdir test -f configure.ac -o -f configure.in ';' ')' \ ! '(' -name preconfigure \ -execdir test -f preconfigure.ac ';' ')' \ -print) and then by running 'make dist-prepare' to regenerate files built from the altered files, and then executing the following to cleanup: chmod a+x sysdeps/unix/sysv/linux/riscv/configure # Omit irrelevant whitespace and comment-only changes, # perhaps from a slightly-different Autoconf version. git checkout -f \ sysdeps/csky/configure \ sysdeps/hppa/configure \ sysdeps/riscv/configure \ sysdeps/unix/sysv/linux/csky/configure # Omit changes that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines git checkout -f \ sysdeps/powerpc/powerpc64/ppc-mcount.S \ sysdeps/unix/sysv/linux/s390/s390-64/syscall.S # Omit change that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
2019-09-07 05:40:42 +00:00
<https://www.gnu.org/licenses/>. */
/* Return: dest
Inputs:
in0: dest
in1: src
In this form, it assumes little endian mode. For big endian mode,
the two shifts in .l2 must be inverted:
shl value = r[1], sh1 // value = w0 << sh1
shr.u tmp = r[0], sh2 // tmp = w1 >> sh2
*/
#include <sysdep.h>
#undef ret
#define saved_lc r15
#define saved_pr r16
#define thresh r17
#define dest r19
#define src r20
#define len r21
#define asrc r22
#define tmp r23
#define pos r24
#define w0 r25
#define w1 r26
#define c r27
#define sh2 r28
#define sh1 r29
#define loopcnt r30
#define value r31
ENTRY(strcpy)
.prologue
alloc r2 = ar.pfs, 2, 0, 30, 32
#define MEMLAT 2
.rotr r[MEMLAT + 2]
.rotp p[MEMLAT + 1]
mov ret0 = in0 // return value = dest
.save pr, saved_pr
mov saved_pr = pr // save the predicate registers
.save ar.lc, saved_lc
mov saved_lc = ar.lc // save the loop counter
.body
sub tmp = r0, in0 ;; // tmp = -dest
mov dest = in0 // dest
mov src = in1 // src
and loopcnt = 7, tmp ;; // loopcnt = -dest % 8
cmp.eq p6, p0 = loopcnt, r0
adds loopcnt = -1, loopcnt // --loopcnt
(p6) br.cond.sptk .dest_aligned ;;
mov ar.lc = loopcnt
.l1: // copy -dest % 8 bytes
ld1 c = [src], 1 // c = *src++
;;
st1 [dest] = c, 1 // *dest++ = c
cmp.eq p6, p0 = c, r0
(p6) br.cond.dpnt .restore_and_exit
br.cloop.dptk .l1 ;;
.dest_aligned:
and sh1 = 7, src // sh1 = src % 8
mov ar.lc = -1 // "infinite" loop
and asrc = -8, src ;; // asrc = src & -OPSIZ -- align src
sub thresh = 8, sh1
mov pr.rot = 1 << 16 // set rotating predicates
cmp.ne p7, p0 = r0, r0 // clear p7
shl sh1 = sh1, 3 ;; // sh1 = 8 * (src % 8)
sub sh2 = 64, sh1 // sh2 = 64 - sh1
cmp.eq p6, p0 = sh1, r0 // is the src aligned?
(p6) br.cond.sptk .src_aligned ;;
ld8 r[1] = [asrc],8 ;;
.align 32
.l2:
ld8.s r[0] = [asrc], 8
shr.u value = r[1], sh1 ;; // value = w0 >> sh1
czx1.r pos = value ;; // do we have an "early" zero
cmp.lt p7, p0 = pos, thresh // in w0 >> sh1?
(p7) br.cond.dpnt .found0
chk.s r[0], .recovery2 // it is safe to do that only
.back2: // after the previous test
shl tmp = r[0], sh2 // tmp = w1 << sh2
;;
or value = value, tmp ;; // value |= tmp
czx1.r pos = value ;;
cmp.ne p7, p0 = 8, pos
(p7) br.cond.dpnt .found0
st8 [dest] = value, 8 // store val to dest
br.ctop.dptk .l2 ;;
.src_aligned:
.l3:
(p[0]) ld8.s r[0] = [src], 8
(p[MEMLAT]) chk.s r[MEMLAT], .recovery3
.back3:
(p[MEMLAT]) mov value = r[MEMLAT]
(p[MEMLAT]) czx1.r pos = r[MEMLAT] ;;
(p[MEMLAT]) cmp.ne p7, p0 = 8, pos
(p7) br.cond.dpnt .found0
(p[MEMLAT]) st8 [dest] = r[MEMLAT], 8
br.ctop.dptk .l3 ;;
.found0:
mov ar.lc = pos
.l4:
extr.u c = value, 0, 8 // c = value & 0xff
shr.u value = value, 8
;;
st1 [dest] = c, 1
br.cloop.dptk .l4 ;;
.restore_and_exit:
mov ar.lc = saved_lc // restore the loop counter
mov pr = saved_pr, -1 // restore the predicate registers
br.ret.sptk.many b0
.recovery2:
add tmp = -8, asrc ;;
ld8 r[0] = [tmp]
br.cond.sptk .back2
.recovery3:
add tmp = -(MEMLAT + 1) * 8, src ;;
ld8 r[MEMLAT] = [tmp]
br.cond.sptk .back3
END(strcpy)
libc_hidden_builtin_def (strcpy)