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| author | Richard Henderson <rth@twiddle.net> | 2014-02-12 06:54:57 -0800 |
|---|---|---|
| committer | Richard Henderson <rth@twiddle.net> | 2014-02-12 07:00:06 -0800 |
| commit | 68b7efaadb1b6045a56277ea62d324c20ac0b633 (patch) | |
| tree | 07b51c9866373430373fb90b252d46c23cc1707e /sysdeps/alpha/ffs.S | |
| parent | 8fd7b0d5591e59ed5cb3078b351bd49314a66cef (diff) | |
| download | glibc-68b7efaadb1b6045a56277ea62d324c20ac0b633.tar.gz glibc-68b7efaadb1b6045a56277ea62d324c20ac0b633.tar.xz glibc-68b7efaadb1b6045a56277ea62d324c20ac0b633.zip | |
Relocate alpha from ports to libc
Also fixed the following whitespace nits to satisfy the push: sysdeps/alpha/alphaev6/memset.S:142: space before tab in indent. sysdeps/alpha/configure:1: new blank line at EOF. sysdeps/alpha/fpu/e_sqrt.c:126: space before tab in indent. sysdeps/alpha/preconfigure:1: new blank line at EOF. sysdeps/unix/sysv/linux/alpha/syscalls.list:1: new blank line at EOF.
Diffstat (limited to 'sysdeps/alpha/ffs.S')
| -rw-r--r-- | sysdeps/alpha/ffs.S | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/sysdeps/alpha/ffs.S b/sysdeps/alpha/ffs.S new file mode 100644 index 0000000000..8d762efb36 --- /dev/null +++ b/sysdeps/alpha/ffs.S @@ -0,0 +1,91 @@ +/* Copyright (C) 1996-2014 Free Software Foundation, Inc. + Contributed by David Mosberger (davidm@cs.arizona.edu). + This file is part of the GNU C Library. + + 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 + <http://www.gnu.org/licenses/>. */ + +/* Finds the first bit set in an integer. Optimized for the Alpha + architecture. */ + +#include <sysdep.h> + + .set noreorder + .set noat + + +ENTRY(__ffs) +#ifdef PROF + ldgp gp, 0(pv) + lda AT, _mcount + jsr AT, (AT), _mcount + .prologue 1 + zap $16, 0xF0, $16 + br $ffsl..ng +#else + .prologue 0 + zap $16, 0xF0, $16 + # FALLTHRU +#endif +END(__ffs) + + .align 4 +ENTRY(ffsl) +#ifdef PROF + ldgp gp, 0(pv) + lda AT, _mcount + jsr AT, (AT), _mcount + .prologue 1 +$ffsl..ng: +#else + .prologue 0 +#endif + not $16, $1 # e0 : + ldi $2, -1 # .. e1 : + cmpbge $1, $2, $3 # e0 : bit N == 1 for byte N == 0 + clr $0 # .. e1 : + addq $3, 1, $4 # e0 : + bic $4, $3, $3 # e1 : bit N == 1 for first byte N != 0 + and $3, 0xF0, $4 # e0 : + and $3, 0xCC, $5 # .. e1 : + and $3, 0xAA, $6 # e0 : + cmovne $4, 4, $0 # .. e1 : + cmovne $5, 2, $5 # e0 : + cmovne $6, 1, $6 # .. e1 : + addl $0, $5, $0 # e0 : + addl $0, $6, $0 # e1 : $0 == N + extbl $16, $0, $1 # e0 : $1 == byte N + ldi $2, 1 # .. e1 : + negq $1, $3 # e0 : + and $3, $1, $3 # e1 : bit N == least bit set of byte N + and $3, 0xF0, $4 # e0 : + and $3, 0xCC, $5 # .. e1 : + and $3, 0xAA, $6 # e0 : + cmovne $4, 5, $2 # .. e1 : + cmovne $5, 2, $5 # e0 : + cmovne $6, 1, $6 # .. e1 : + s8addl $0, $2, $0 # e0 : mult byte ofs by 8 and sum + addl $5, $6, $5 # .. e1 : + addl $0, $5, $0 # e0 : + nop # .. e1 : + cmoveq $16, 0, $0 # e0 : trap input == 0 case. + ret # .. e1 : 18 + +END(ffsl) + +weak_alias (__ffs, ffs) +libc_hidden_def (__ffs) +libc_hidden_builtin_def (ffs) +weak_extern (ffsl) +weak_alias (ffsl, ffsll) |