	.386
	.model use32 small
	public _strupr
	.code
_strupr:
	push	esi
	mov	esi,[esp+8]
lp:
	lodsb
	or	al,al
	jz	strx
	cmp	al,'a'
	jc	lp
	cmp	al,'z'
	ja	lp
	and	al, NOT 20h
	mov	[esi-1],al
	jmp	lp

strx:
	mov	eax,[esp + 8]
	pop	esi
	ret
	end