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#       memset()                                        Author: Kees J. Bot
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/*	memset()					Author: Kees J. Bot */
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#                                                               2 Jan 1994
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# void *memset(void *s, int c, size_t n)
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/*								2 Jan 1994 */
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#       Set a chunk of memory to the same byte value.
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#
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/* void *memset(void *s, int c, size_t n) */
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/*	Set a chunk of memory to the same byte value. */
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/* */
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.intel_syntax
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.global _memset
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        .text
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#include "asm.h"
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	.align	16
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_memset:
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ENTRY(memset)
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        push  ebp
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	push	%ebp
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        mov ebp, esp
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	movl	%esp, %ebp
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        push  edi
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	push	%edi
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        mov     edi, [8+ebp]     # The string
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	movl	8(%ebp), %edi	/* The string */
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        movzx   eax, byte ptr [12+ebp]    # The fill byte
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	movzbl	12(%ebp), %eax	/* The fill byte */
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        mov     ecx, [16+ebp]    # Length
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	movl	16(%ebp), %ecx	/* Length */
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        cld
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	cld
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        cmp ecx, 16
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	cmpl	$16, %ecx
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        jb      sbyte           # Don't bother being smart with short arrays
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	jb	sbyte	/* Don't bother being smart with short arrays */
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        test  edi, 1
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	testl	$1, %edi
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        jnz     sbyte           # Bit 0 set, use byte store
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	jne	sbyte	/* Bit 0 set, use byte store */
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        test  edi, 2
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	testl	$2, %edi
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        jnz     sword           # Bit 1 set, use word store
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	jne	sword	/* Bit 1 set, use word store */
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slword:
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slword:
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        movb    ah, al
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	movb	%al, %ah
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        mov edx, eax
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	movl	%eax, %edx
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        sal edx, 16
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	sall	$16, %edx
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        or      eax, edx        # One byte to four bytes
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	orl	%edx, %eax	/* One byte to four bytes */
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	shrdl	$2, %ecx, %edx	/* Save low two bits of ecx in edx */
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        shrd    edx, ecx, 2     # Save low two bits of ecx in edx
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	shrl	$2, %ecx
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        shr ecx, 2
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        rep     stosd           # Store longwords.
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	rep stosl	/* Store longwords. */
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        shld    ecx, edx, 2     # Restore low two bits
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	shldl	$2, %edx, %ecx	/* Restore low two bits */
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        sword:
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sword:
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	movb	%al, %ah	/* One byte to two bytes */
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        movb    ah, al          # One byte to two bytes
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	shrl	$1, %ecx
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        shr ecx, 1
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        rep     stosw           # Store words
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	rep stosw	/* Store words */
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        adc     ecx, ecx        # One more byte?
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	adcl	%ecx, %ecx	/* One more byte? */
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sbyte:
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sbyte:
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        rep     stosb           # Store bytes
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	rep stosb	/* Store bytes */
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done:
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done:
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        mov     eax, [8+ebp]    # Return some value you have no need for
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	movl	8(%ebp), %eax	/* Return some value you have no need for */
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        pop edi
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	pop	%edi