diff options
Diffstat (limited to 'arch/frv/lib/memset.S')
| -rw-r--r-- | arch/frv/lib/memset.S | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/arch/frv/lib/memset.S b/arch/frv/lib/memset.S new file mode 100644 index 00000000000..55a35263cbe --- /dev/null +++ b/arch/frv/lib/memset.S @@ -0,0 +1,182 @@ +/* memset.S: optimised assembly memset + * + * Copyright (C) 2003 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + + + .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,__memset_end + .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 +__memset_end: + + .size memset, __memset_end-memset + +############################################################################### +# +# clear memory in userspace +# - return the number of bytes that could not be cleared (0 on complete success) +# +# long __memset_user(void *p, size_t count) +# +############################################################################### + .globl __memset_user, __memset_user_error_lr, __memset_user_error_handler + .type __memset_user,@function +__memset_user: + movsg lr,gr11 + + # abuse memset to do the dirty work + or.p gr9,gr9,gr10 + setlos #0,gr9 + call memset +__memset_user_error_lr: + jmpl.p @(gr11,gr0) + setlos #0,gr8 + + # deal any exception generated by memset + # GR4 - memset's address tracking pointer + # GR7 - memset's step value (index register for store insns) + # GR8 - memset's original start address + # GR10 - memset's original count +__memset_user_error_handler: + add.p gr4,gr7,gr4 + add gr8,gr10,gr8 + jmpl.p @(gr11,gr0) + sub gr8,gr4,gr8 ; we return the amount left uncleared + + .size __memset_user, .-__memset_user |