glibc/sysdeps/alpha/alphaev6/memcpy.S
Paul Eggert 5a82c74822 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 02:43:31 -07:00

256 lines
6.7 KiB
ArmAsm

/* Copyright (C) 2000-2019 Free Software Foundation, Inc.
This file is part of the GNU C Library.
EV6 optimized by Rick Gorton <rick.gorton@alpha-processor.com>.
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/>. */
/*
* Much of the information about 21264 scheduling/coding comes from:
* Compiler Writer's Guide for the Alpha 21264
* abbreviated as 'CWG' in other comments here
* ftp.digital.com/pub/Digital/info/semiconductor/literature/dsc-library.html
* Scheduling notation:
* E - either cluster
* U - upper subcluster; U0 - subcluster U0; U1 - subcluster U1
* L - lower subcluster; L0 - subcluster L0; L1 - subcluster L1
*
* Temp usage notes:
* $0 - destination address
* $1,$2, - scratch
*/
#include <sysdep.h>
.arch ev6
.set noreorder
.set noat
ENTRY(memcpy)
.prologue 0
mov $16, $0 # E : copy dest to return
ble $18, $nomoredata # U : done with the copy?
xor $16, $17, $1 # E : are source and dest alignments the same?
and $1, 7, $1 # E : are they the same mod 8?
bne $1, $misaligned # U : Nope - gotta do this the slow way
/* source and dest are same mod 8 address */
and $16, 7, $1 # E : Are both 0mod8?
beq $1, $both_0mod8 # U : Yes
nop # E :
/*
* source and dest are same misalignment. move a byte at a time
* until a 0mod8 alignment for both is reached.
* At least one byte more to move
*/
$head_align:
ldbu $1, 0($17) # L : grab a byte
subq $18, 1, $18 # E : count--
addq $17, 1, $17 # E : src++
stb $1, 0($16) # L :
addq $16, 1, $16 # E : dest++
and $16, 7, $1 # E : Are we at 0mod8 yet?
ble $18, $nomoredata # U : done with the copy?
bne $1, $head_align # U :
$both_0mod8:
cmple $18, 127, $1 # E : Can we unroll the loop?
bne $1, $no_unroll # U :
and $16, 63, $1 # E : get mod64 alignment
beq $1, $do_unroll # U : no single quads to fiddle
$single_head_quad:
ldq $1, 0($17) # L : get 8 bytes
subq $18, 8, $18 # E : count -= 8
addq $17, 8, $17 # E : src += 8
nop # E :
stq $1, 0($16) # L : store
addq $16, 8, $16 # E : dest += 8
and $16, 63, $1 # E : get mod64 alignment
bne $1, $single_head_quad # U : still not fully aligned
$do_unroll:
addq $16, 64, $7 # E : Initial (+1 trip) wh64 address
cmple $18, 127, $1 # E : Can we go through the unrolled loop?
bne $1, $tail_quads # U : Nope
nop # E :
$unroll_body:
wh64 ($7) # L1 : memory subsystem hint: 64 bytes at
# ($7) are about to be over-written
ldq $6, 0($17) # L0 : bytes 0..7
nop # E :
nop # E :
ldq $4, 8($17) # L : bytes 8..15
ldq $5, 16($17) # L : bytes 16..23
addq $7, 64, $7 # E : Update next wh64 address
nop # E :
ldq $3, 24($17) # L : bytes 24..31
addq $16, 64, $1 # E : fallback value for wh64
nop # E :
nop # E :
addq $17, 32, $17 # E : src += 32 bytes
stq $6, 0($16) # L : bytes 0..7
nop # E :
nop # E :
stq $4, 8($16) # L : bytes 8..15
stq $5, 16($16) # L : bytes 16..23
subq $18, 192, $2 # E : At least two more trips to go?
nop # E :
stq $3, 24($16) # L : bytes 24..31
addq $16, 32, $16 # E : dest += 32 bytes
nop # E :
nop # E :
ldq $6, 0($17) # L : bytes 0..7
ldq $4, 8($17) # L : bytes 8..15
cmovlt $2, $1, $7 # E : Latency 2, extra map slot - Use
# fallback wh64 address if < 2 more trips
nop # E :
ldq $5, 16($17) # L : bytes 16..23
ldq $3, 24($17) # L : bytes 24..31
addq $16, 32, $16 # E : dest += 32
subq $18, 64, $18 # E : count -= 64
addq $17, 32, $17 # E : src += 32
stq $6, -32($16) # L : bytes 0..7
stq $4, -24($16) # L : bytes 8..15
cmple $18, 63, $1 # E : At least one more trip?
stq $5, -16($16) # L : bytes 16..23
stq $3, -8($16) # L : bytes 24..31
nop # E :
beq $1, $unroll_body
$tail_quads:
$no_unroll:
.align 4
subq $18, 8, $18 # E : At least a quad left?
blt $18, $less_than_8 # U : Nope
nop # E :
nop # E :
$move_a_quad:
ldq $1, 0($17) # L : fetch 8
subq $18, 8, $18 # E : count -= 8
addq $17, 8, $17 # E : src += 8
nop # E :
stq $1, 0($16) # L : store 8
addq $16, 8, $16 # E : dest += 8
bge $18, $move_a_quad # U :
nop # E :
$less_than_8:
.align 4
addq $18, 8, $18 # E : add back for trailing bytes
ble $18, $nomoredata # U : All-done
nop # E :
nop # E :
/* Trailing bytes */
$tail_bytes:
subq $18, 1, $18 # E : count--
ldbu $1, 0($17) # L : fetch a byte
addq $17, 1, $17 # E : src++
nop # E :
stb $1, 0($16) # L : store a byte
addq $16, 1, $16 # E : dest++
bgt $18, $tail_bytes # U : more to be done?
nop # E :
/* branching to exit takes 3 extra cycles, so replicate exit here */
ret $31, ($26), 1 # L0 :
nop # E :
nop # E :
nop # E :
$misaligned:
mov $0, $4 # E : dest temp
and $0, 7, $1 # E : dest alignment mod8
beq $1, $dest_0mod8 # U : life doesnt totally suck
nop
$aligndest:
ble $18, $nomoredata # U :
ldbu $1, 0($17) # L : fetch a byte
subq $18, 1, $18 # E : count--
addq $17, 1, $17 # E : src++
stb $1, 0($4) # L : store it
addq $4, 1, $4 # E : dest++
and $4, 7, $1 # E : dest 0mod8 yet?
bne $1, $aligndest # U : go until we are aligned.
/* Source has unknown alignment, but dest is known to be 0mod8 */
$dest_0mod8:
subq $18, 8, $18 # E : At least a quad left?
blt $18, $misalign_tail # U : Nope
ldq_u $3, 0($17) # L : seed (rotating load) of 8 bytes
nop # E :
$mis_quad:
ldq_u $16, 8($17) # L : Fetch next 8
extql $3, $17, $3 # U : masking
extqh $16, $17, $1 # U : masking
bis $3, $1, $1 # E : merged bytes to store
subq $18, 8, $18 # E : count -= 8
addq $17, 8, $17 # E : src += 8
stq $1, 0($4) # L : store 8 (aligned)
mov $16, $3 # E : "rotate" source data
addq $4, 8, $4 # E : dest += 8
bge $18, $mis_quad # U : More quads to move
nop
nop
$misalign_tail:
addq $18, 8, $18 # E : account for tail stuff
ble $18, $nomoredata # U :
nop
nop
$misalign_byte:
ldbu $1, 0($17) # L : fetch 1
subq $18, 1, $18 # E : count--
addq $17, 1, $17 # E : src++
nop # E :
stb $1, 0($4) # L : store
addq $4, 1, $4 # E : dest++
bgt $18, $misalign_byte # U : more to go?
nop
$nomoredata:
ret $31, ($26), 1 # L0 :
nop # E :
nop # E :
nop # E :
END(memcpy)
libc_hidden_builtin_def (memcpy)