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- /* memset.S: optimised assembly memset
- *
- * Copyright (C) 2003, 2004 Red Hat, Inc. All Rights Reserved.
- * Written by David Howells (dhowells@redhat.com)
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Library General Public
- * License as published by the Free Software Foundation; either
- * version 2 of the License, or (at your option) any later version.
- *
- * This 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
- * Library General Public License for more details.
- *
- * You should have received a copy of the GNU Library General Public
- * License along with this library; if not, see
- * <http://www.gnu.org/licenses/>.
- */
- #include <features.h>
- .text
- .p2align 4
- ###############################################################################
- #
- # void *memset(void *p, char ch, size_t count)
- #
- # - NOTE: must not use any stack. exception detection performs function return
- # to caller's fixup routine, aborting the remainder of the set
- # GR4, GR7, GR8, and GR11 must be managed
- #
- ###############################################################################
- .globl memset
- .type memset,@function
- memset:
- orcc.p gr10,gr0,gr5,icc3 ; GR5 = count
- andi gr9,#0xff,gr9
- or.p gr8,gr0,gr4 ; GR4 = address
- beqlr icc3,#0
- # conditionally write a byte to 2b-align the address
- setlos.p #1,gr6
- andicc gr4,#1,gr0,icc0
- ckne icc0,cc7
- cstb.p gr9,@(gr4,gr0) ,cc7,#1
- csubcc gr5,gr6,gr5 ,cc7,#1 ; also set ICC3
- cadd.p gr4,gr6,gr4 ,cc7,#1
- beqlr icc3,#0
- # conditionally write a word to 4b-align the address
- andicc.p gr4,#2,gr0,icc0
- subicc gr5,#2,gr0,icc1
- setlos.p #2,gr6
- ckne icc0,cc7
- slli.p gr9,#8,gr12 ; need to double up the pattern
- cknc icc1,cc5
- or.p gr9,gr12,gr12
- andcr cc7,cc5,cc7
- csth.p gr12,@(gr4,gr0) ,cc7,#1
- csubcc gr5,gr6,gr5 ,cc7,#1 ; also set ICC3
- cadd.p gr4,gr6,gr4 ,cc7,#1
- beqlr icc3,#0
- # conditionally write a dword to 8b-align the address
- andicc.p gr4,#4,gr0,icc0
- subicc gr5,#4,gr0,icc1
- setlos.p #4,gr6
- ckne icc0,cc7
- slli.p gr12,#16,gr13 ; need to quadruple-up the pattern
- cknc icc1,cc5
- or.p gr13,gr12,gr12
- andcr cc7,cc5,cc7
- cst.p gr12,@(gr4,gr0) ,cc7,#1
- csubcc gr5,gr6,gr5 ,cc7,#1 ; also set ICC3
- cadd.p gr4,gr6,gr4 ,cc7,#1
- beqlr icc3,#0
- or.p gr12,gr12,gr13 ; need to octuple-up the pattern
- # the address is now 8b-aligned - loop around writing 64b chunks
- setlos #8,gr7
- subi.p gr4,#8,gr4 ; store with update index does weird stuff
- setlos #64,gr6
- subicc gr5,#64,gr0,icc0
- 0: cknc icc0,cc7
- cstdu gr12,@(gr4,gr7) ,cc7,#1
- cstdu gr12,@(gr4,gr7) ,cc7,#1
- cstdu gr12,@(gr4,gr7) ,cc7,#1
- cstdu gr12,@(gr4,gr7) ,cc7,#1
- cstdu gr12,@(gr4,gr7) ,cc7,#1
- cstdu.p gr12,@(gr4,gr7) ,cc7,#1
- csubcc gr5,gr6,gr5 ,cc7,#1 ; also set ICC3
- cstdu.p gr12,@(gr4,gr7) ,cc7,#1
- subicc gr5,#64,gr0,icc0
- cstdu.p gr12,@(gr4,gr7) ,cc7,#1
- beqlr icc3,#0
- bnc icc0,#2,0b
- # now do 32-byte remnant
- subicc.p gr5,#32,gr0,icc0
- setlos #32,gr6
- cknc icc0,cc7
- cstdu.p gr12,@(gr4,gr7) ,cc7,#1
- csubcc gr5,gr6,gr5 ,cc7,#1 ; also set ICC3
- cstdu.p gr12,@(gr4,gr7) ,cc7,#1
- setlos #16,gr6
- cstdu.p gr12,@(gr4,gr7) ,cc7,#1
- subicc gr5,#16,gr0,icc0
- cstdu.p gr12,@(gr4,gr7) ,cc7,#1
- beqlr icc3,#0
- # now do 16-byte remnant
- cknc icc0,cc7
- cstdu.p gr12,@(gr4,gr7) ,cc7,#1
- csubcc gr5,gr6,gr5 ,cc7,#1 ; also set ICC3
- cstdu.p gr12,@(gr4,gr7) ,cc7,#1
- beqlr icc3,#0
- # now do 8-byte remnant
- subicc gr5,#8,gr0,icc1
- cknc icc1,cc7
- cstdu.p gr12,@(gr4,gr7) ,cc7,#1
- csubcc gr5,gr7,gr5 ,cc7,#1 ; also set ICC3
- setlos.p #4,gr7
- beqlr icc3,#0
- # now do 4-byte remnant
- subicc gr5,#4,gr0,icc0
- addi.p gr4,#4,gr4
- cknc icc0,cc7
- cstu.p gr12,@(gr4,gr7) ,cc7,#1
- csubcc gr5,gr7,gr5 ,cc7,#1 ; also set ICC3
- subicc.p gr5,#2,gr0,icc1
- beqlr icc3,#0
- # now do 2-byte remnant
- setlos #2,gr7
- addi.p gr4,#2,gr4
- cknc icc1,cc7
- csthu.p gr12,@(gr4,gr7) ,cc7,#1
- csubcc gr5,gr7,gr5 ,cc7,#1 ; also set ICC3
- subicc.p gr5,#1,gr0,icc0
- beqlr icc3,#0
- # now do 1-byte remnant
- setlos #0,gr7
- addi.p gr4,#2,gr4
- cknc icc0,cc7
- cstb.p gr12,@(gr4,gr0) ,cc7,#1
- bralr
- .size memset, .-memset
- libc_hidden_def(memset)
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