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/* Copyright (C) 1995 DJ Delorie, see COPYING.DJ for details */

##include

#  .file "memset.s"

	.text

        .global _memset

	.align	4

_memset:

	pushl	%ebp

	movl	%esp,%ebp

	pushl	%edi

	movl	8(%ebp),%edi

	movl	12(%ebp),%eax

	movl	16(%ebp),%ecx

	cld

	# We will handle memsets of <= 15 bytes one byte at a time.

	# This avoids some extra overhead for small memsets, and

	# knowing we are setting > 15 bytes eliminates some annoying

	# checks in the "long move" case.

	cmpl	$15,%ecx

	jle	L3

	# Otherwise, tile the byte value out into %eax.

	# 0x41 -> 0x41414141, etc.

	movb	%al,%ah

	movl	%eax,%edx

	sall	$16,%eax

	movw	%dx,%ax

	jmp	L2

	# Handle any cruft necessary to get %edi long-aligned.

L1:	stosb

	decl	%ecx

L2:	testl	$3,%edi

	jnz	L1

	# Now slam out all of the longs.

	movl	%ecx,%edx

	shrl	$2,%ecx

	rep

	stosl

	# Finally, handle any trailing cruft.  We know the high three bytes

	# of %ecx must be zero, so just put the "slop count" in the low byte.

	movb	%dl,%cl

	andb	$3,%cl

L3:	rep

	stosb

	popl	%edi

	movl	8(%ebp),%eax

	leave

	ret