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Diffstat (limited to 'sysdeps/alpha/bzero.S')
| -rw-r--r-- | sysdeps/alpha/bzero.S | 120 |
1 files changed, 0 insertions, 120 deletions
diff --git a/sysdeps/alpha/bzero.S b/sysdeps/alpha/bzero.S deleted file mode 100644 index 87e575babb..0000000000 --- a/sysdeps/alpha/bzero.S +++ /dev/null @@ -1,120 +0,0 @@ -/* Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc. - Contributed by Richard Henderson (rth@tamu.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, write to the Free - Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA - 02111-1307 USA. */ - -/* Fill a block of memory with zeros. Optimized for the Alpha architecture: - - - memory accessed as aligned quadwords only - - destination memory not read unless needed for good cache behaviour - - basic blocks arranged to optimize branch prediction for full-quadword - aligned memory blocks. - - partial head and tail quadwords constructed with byte-mask instructions - - This is generally scheduled for the EV5 (got to look out for my own - interests :-), but with EV4 needs in mind. There *should* be no more - stalls for the EV4 than there are for the EV5. -*/ - - -#include <sysdep.h> - - .set noat - .set noreorder - - .text - -/* There is a problem with either gdb (as of 4.16) or gas (as of 2.7) that - doesn't like putting the entry point for a procedure somewhere in the - middle of the procedure descriptor. Work around this by putting the main - loop in its own procedure descriptor. */ - - /* On entry to this basic block: - t3 == loop counter - t4 == bytes in partial final word - a0 == possibly misaligned destination pointer */ - - .ent bzero_loop - .align 3 -bzero_loop: - .frame sp, 0, ra, 0 - .prologue 0 - - beq t3, $tail # - blbc t3, 0f # skip single store if count even - - stq_u zero, 0(a0) # e0 : store one word - subq t3, 1, t3 # .. e1 : - addq a0, 8, a0 # e0 : - beq t3, $tail # .. e1 : - -0: stq_u zero, 0(a0) # e0 : store two words - subq t3, 2, t3 # .. e1 : - stq_u zero, 8(a0) # e0 : - addq a0, 16, a0 # .. e1 : - bne t3, 0b # e1 : - -$tail: bne t4, 1f # is there a tail to do? - ret # no - -1: ldq_u t0, 0(a0) # yes, load original data - mskqh t0, t4, t0 # - stq_u t0, 0(a0) # - ret # - - .end bzero_loop - -ENTRY(__bzero) -#ifdef PROF - ldgp gp, 0(pv) - lda AT, _mcount - jsr AT, (AT), _mcount - .prologue 1 -#else - .prologue 0 -#endif - - mov a0, v0 # e0 : move return value in place - beq a1, $done # .. e1 : early exit for zero-length store - and a0, 7, t1 # e0 : - addq a1, t1, a1 # e1 : add dest misalignment to count - srl a1, 3, t3 # e0 : loop = count >> 3 - and a1, 7, t4 # .. e1 : find number of bytes in tail - unop # : - beq t1, bzero_loop # e1 : aligned head, jump right in - - ldq_u t0, 0(a0) # e0 : load original data to mask into - cmpult a1, 8, t2 # .. e1 : is this a sub-word set? - bne t2, $oneq # e1 : - - mskql t0, a0, t0 # e0 : we span words. finish this partial - subq t3, 1, t3 # e0 : - addq a0, 8, a0 # .. e1 : - stq_u t0, -8(a0) # e0 : - br bzero_loop # .. e1 : - - .align 3 -$oneq: - mskql t0, a0, t2 # e0 : - mskqh t0, a1, t3 # e0 : - or t2, t3, t0 # e1 : - stq_u t0, 0(a0) # e0 : - -$done: ret - - END(__bzero) -weak_alias (__bzero, bzero) |