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-rw-r--r--arch/mips/lib/memset.S166
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diff --git a/arch/mips/lib/memset.S b/arch/mips/lib/memset.S
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+++ b/arch/mips/lib/memset.S
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+/*
+ * 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