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From: rhm@druwy.ATT.COM (Roger Massey)
Newsgroups: comp.sys.ibm.pc
Subject: TC2.0 bugfree ?
Message-ID: <3785@druwy.ATT.COM>
Date: 20 Jan 89 00:39:46 GMT
Reply-To: rhm@druwy.UUCP (MasseyR)
Organization: AT&T, Denver, CO
Lines: 49

No bugs in TC2.0 ?

This small model C program :

sub( cp )
unsigned char 	*cp;
{
	int 	i;

	i = (*cp++ << 8) + *cp++;
}

generates the following code fragment (I left out some of the .asm):
	

_TEXT	segment	byte public 'CODE'
;	?debug	L 1
_sub	proc	near
	push	bp
	mov	bp,sp
	sub	sp,2
	push	si
	mov	si,word ptr [bp+4]
;	?debug	L 6
	mov	al,byte ptr [si]
	mov	ah,0
	mov	cl,8
	shl	ax,cl
	mov	dl,byte ptr [si]
	mov	dh,0
	add	ax,dx
	mov	word ptr [bp-2],ax
	inc	si
	inc	si
@1:
;	?debug	L 7
	pop	si
	mov	sp,bp
	pop	bp
	ret	
_sub	endp
_TEXT	ends


note that si (i.e. cp) is not incremented between references
but instead after both references.

Roger Massey
AT&T  Denver