diff options
Diffstat (limited to 'sysdeps/alpha/rawmemchr.S')
-rw-r--r-- | sysdeps/alpha/rawmemchr.S | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/sysdeps/alpha/rawmemchr.S b/sysdeps/alpha/rawmemchr.S new file mode 100644 index 0000000000..4a06421f48 --- /dev/null +++ b/sysdeps/alpha/rawmemchr.S @@ -0,0 +1,89 @@ +/* Copyright (C) 2000-2014 Free Software Foundation, Inc. + 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/>. */ + +/* Return pointer to first occurrence of CH in STR. */ + +#include <sysdep.h> + + .set noreorder + .set noat + +ENTRY(__rawmemchr) +#ifdef PROF + ldgp gp, 0(pv) + lda AT, _mcount + jsr AT, (AT), _mcount + .prologue 1 +#else + .prologue 0 +#endif + + zapnot a1, 1, a1 # e0 : zero extend the search character + ldq_u t0, 0(a0) # .. e1 : load first quadword + sll a1, 8, t5 # e0 : replicate the search character + andnot a0, 7, v0 # .. e1 : align our loop pointer + + or t5, a1, a1 # e0 : + lda t4, -1 # .. e1 : build garbage mask + sll a1, 16, t5 # e0 : + unop # : + + mskqh t4, a0, t4 # e0 : + or t5, a1, a1 # .. e1 : + sll a1, 32, t5 # e0 : + cmpbge zero, t4, t4 # .. e1 : bits set iff byte is garbage + + or t5, a1, a1 # e0 : + xor t0, a1, t1 # .. e1 : make bytes == c zero + cmpbge zero, t1, t3 # e0 : bits set iff byte == c + unop # : + + andnot t3, t4, t0 # e0 : clear garbage bits + fnop # .. fa : + unop # : + bne t0, $found # .. e1 (zdb) + + .align 4 +$loop: + ldq t0, 8(v0) # e0 : + addq v0, 8, v0 # .. e1 : + nop # e0 : + xor t0, a1, t1 # .. e1 (ev5 data stall) + + cmpbge zero, t1, t0 # e0 : bits set iff byte == c + beq t0, $loop # .. e1 (zdb) + +$found: + negq t0, t1 # e0 : clear all but least set bit + and t0, t1, t0 # e1 (stall) + and t0, 0xf0, t2 # e0 : binary search for that set bit + and t0, 0xcc, t3 # .. e1 : + + and t0, 0xaa, t4 # e0 : + cmovne t2, 4, t2 # .. e1 : + cmovne t3, 2, t3 # e0 : + cmovne t4, 1, t4 # .. e1 : + + addq t2, t3, t2 # e0 : + addq v0, t4, v0 # .. e1 : + addq v0, t2, v0 # e0 : + ret # .. e1 : + + END(__rawmemchr) + +libc_hidden_def (__rawmemchr) +weak_alias (__rawmemchr, rawmemchr) |