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Bug#85535: acknowledged by developer (Bug#85535: fixed in gcc-3.3 1:3.3ds9-1)

reopen 85535

On Sat, May 17, 2003 at 04:51:38PM -0500, Debian Bug Tracking System wrote:
> This is an automatic notification regarding your Bug report
> #85535: [fixed in gcc-3.1, PR optimization/3508]: builtin memcmp() could be optimised,
> which was filed against the gcc package.
> It has been closed by one of the developers, namely
> Matthias Klose <doko@debian.org>.

Unfortunately this bug has only been special cased rather than fixed
in its full generality.  If we change one of the arguments to a
variable, the compiler still fails to produce the dword comparison
that I would expect:

-- a.c --
int foo(const char *s) {
	return !memcmp("abcd", s, 4);

-- gcc -S -O2 a.c --
	.string	"abcd"
	.p2align 2,,3
.globl foo
	.type	foo, @function
	pushl	%ebp
	movl	%esp, %ebp
	pushl	%edi
	pushl	%esi
	movl	8(%ebp), %edi
	movl	$.LC0, %esi
	movl	$4, %ecx
	sete	%al
	popl	%esi
	movzbl	%al, %eax
	popl	%edi
	.size	foo, .-foo
	.ident	"GCC: (GNU) 3.3 20030509 (Debian prerelease)"
Debian GNU/Linux 3.0 is out! ( http://www.debian.org/ )
Email:  Herbert Xu ~{PmV>HI~} <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

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