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Diffstat (limited to 'arch/mips/lib/memset.S')
| -rw-r--r-- | arch/mips/lib/memset.S | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/arch/mips/lib/memset.S b/arch/mips/lib/memset.S new file mode 100644 index 0000000..3f8b8b3 --- /dev/null +++ b/arch/mips/lib/memset.S @@ -0,0 +1,166 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 1998, 1999, 2000 by Ralf Baechle + * Copyright (C) 1999, 2000 Silicon Graphics, Inc. + */ +#include <asm/asm.h> +#include <asm/asm-offsets.h> +#include <asm/regdef.h> + +#if LONGSIZE == 4 +#define LONG_S_L swl +#define LONG_S_R swr +#else +#define LONG_S_L sdl +#define LONG_S_R sdr +#endif + +#define EX(insn,reg,addr,handler) \ +9: insn reg, addr; \ + .section __ex_table,"a"; \ + PTR 9b, handler; \ + .previous + + .macro f_fill64 dst, offset, val, fixup + EX(LONG_S, \val, (\offset + 0 * LONGSIZE)(\dst), \fixup) + EX(LONG_S, \val, (\offset + 1 * LONGSIZE)(\dst), \fixup) + EX(LONG_S, \val, (\offset + 2 * LONGSIZE)(\dst), \fixup) + EX(LONG_S, \val, (\offset + 3 * LONGSIZE)(\dst), \fixup) + EX(LONG_S, \val, (\offset + 4 * LONGSIZE)(\dst), \fixup) + EX(LONG_S, \val, (\offset + 5 * LONGSIZE)(\dst), \fixup) + EX(LONG_S, \val, (\offset + 6 * LONGSIZE)(\dst), \fixup) + EX(LONG_S, \val, (\offset + 7 * LONGSIZE)(\dst), \fixup) +#if LONGSIZE == 4 + EX(LONG_S, \val, (\offset + 8 * LONGSIZE)(\dst), \fixup) + EX(LONG_S, \val, (\offset + 9 * LONGSIZE)(\dst), \fixup) + EX(LONG_S, \val, (\offset + 10 * LONGSIZE)(\dst), \fixup) + EX(LONG_S, \val, (\offset + 11 * LONGSIZE)(\dst), \fixup) + EX(LONG_S, \val, (\offset + 12 * LONGSIZE)(\dst), \fixup) + EX(LONG_S, \val, (\offset + 13 * LONGSIZE)(\dst), \fixup) + EX(LONG_S, \val, (\offset + 14 * LONGSIZE)(\dst), \fixup) + EX(LONG_S, \val, (\offset + 15 * LONGSIZE)(\dst), \fixup) +#endif + .endm + +/* + * memset(void *s, int c, size_t n) + * + * a0: start of area to clear + * a1: char to fill with + * a2: size of area to clear + */ + .set noreorder + .align 5 +LEAF(memset) + beqz a1, 1f + move v0, a0 /* result */ + + andi a1, 0xff /* spread fillword */ + LONG_SLL t1, a1, 8 + or a1, t1 + LONG_SLL t1, a1, 16 +#if LONGSIZE == 8 + or a1, t1 + LONG_SLL t1, a1, 32 +#endif + or a1, t1 +1: + +FEXPORT(__bzero) + sltiu t0, a2, LONGSIZE /* very small region? */ + bnez t0, small_memset + andi t0, a0, LONGMASK /* aligned? */ + + beqz t0, 1f + PTR_SUBU t0, LONGSIZE /* alignment in bytes */ + +#ifdef __MIPSEB__ + EX(LONG_S_L, a1, (a0), first_fixup) /* make word/dword aligned */ +#endif +#ifdef __MIPSEL__ + EX(LONG_S_R, a1, (a0), first_fixup) /* make word/dword aligned */ +#endif + PTR_SUBU a0, t0 /* long align ptr */ + PTR_ADDU a2, t0 /* correct size */ + +1: ori t1, a2, 0x3f /* # of full blocks */ + xori t1, 0x3f + beqz t1, memset_partial /* no block to fill */ + andi t0, a2, 0x40-LONGSIZE + + PTR_ADDU t1, a0 /* end address */ + .set reorder +1: PTR_ADDIU a0, 64 + f_fill64 a0, -64, a1, fwd_fixup + bne t1, a0, 1b + .set noreorder + +memset_partial: + PTR_LA t1, 2f /* where to start */ +#if LONGSIZE == 4 + PTR_SUBU t1, t0 +#else + .set noat + LONG_SRL AT, t0, 1 + PTR_SUBU t1, AT + .set noat +#endif + jr t1 + PTR_ADDU a0, t0 /* dest ptr */ + + .set push + .set noreorder + .set nomacro + f_fill64 a0, -64, a1, partial_fixup /* ... but first do longs ... */ +2: .set pop + andi a2, LONGMASK /* At most one long to go */ + + beqz a2, 1f + PTR_ADDU a0, a2 /* What's left */ +#ifdef __MIPSEB__ + EX(LONG_S_R, a1, -1(a0), last_fixup) +#endif +#ifdef __MIPSEL__ + EX(LONG_S_L, a1, -1(a0), last_fixup) +#endif +1: jr ra + move a2, zero + +small_memset: + beqz a2, 2f + PTR_ADDU t1, a0, a2 + +1: PTR_ADDIU a0, 1 /* fill bytewise */ + bne t1, a0, 1b + sb a1, -1(a0) + +2: jr ra /* done */ + move a2, zero + END(memset) + +first_fixup: + jr ra + nop + +fwd_fixup: + PTR_L t0, TI_TASK($28) + LONG_L t0, THREAD_BUADDR(t0) + andi a2, 0x3f + LONG_ADDU a2, t1 + jr ra + LONG_SUBU a2, t0 + +partial_fixup: + PTR_L t0, TI_TASK($28) + LONG_L t0, THREAD_BUADDR(t0) + andi a2, LONGMASK + LONG_ADDU a2, t1 + jr ra + LONG_SUBU a2, t0 + +last_fixup: + jr ra + andi v1, a2, LONGMASK |