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@@ -0,0 +1,52 @@
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+/*
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+ * linux/arch/arm/lib/clear_user.S
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+ *
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+ * Copyright (C) 1995, 1996,1997,1998 Russell King
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+ *
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+ * This program is free software; you can redistribute it and/or modify
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+ * it under the terms of the GNU General Public License version 2 as
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+ * published by the Free Software Foundation.
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+ */
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+#include <linux/linkage.h>
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+#include <asm/assembler.h>
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+
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+ .text
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+
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+/* Prototype: int __arch_clear_user(void *addr, size_t sz)
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+ * Purpose : clear some user memory
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+ * Params : addr - user memory address to clear
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+ * : sz - number of bytes to clear
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+ * Returns : number of bytes NOT cleared
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+ */
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+ENTRY(__arch_clear_user)
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+ stmfd sp!, {r1, lr}
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+ mov r2, #0
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+ cmp r1, #4
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+ blt 2f
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+ ands ip, r0, #3
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+ beq 1f
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+ cmp ip, #2
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+USER( strbt r2, [r0], #1)
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+USER( strlebt r2, [r0], #1)
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+USER( strltbt r2, [r0], #1)
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+ rsb ip, ip, #4
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+ sub r1, r1, ip @ 7 6 5 4 3 2 1
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+1: subs r1, r1, #8 @ -1 -2 -3 -4 -5 -6 -7
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+USER( strplt r2, [r0], #4)
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+USER( strplt r2, [r0], #4)
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+ bpl 1b
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+ adds r1, r1, #4 @ 3 2 1 0 -1 -2 -3
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+USER( strplt r2, [r0], #4)
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+2: tst r1, #2 @ 1x 1x 0x 0x 1x 1x 0x
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+USER( strnebt r2, [r0], #1)
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+USER( strnebt r2, [r0], #1)
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+ tst r1, #1 @ x1 x0 x1 x0 x1 x0 x1
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+USER( strnebt r2, [r0], #1)
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+ mov r0, #0
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+ LOADREGS(fd,sp!, {r1, pc})
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+
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+ .section .fixup,"ax"
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+ .align 0
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+9001: LOADREGS(fd,sp!, {r0, pc})
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+ .previous
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+
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