[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Bug#602785: marked as done (gcc-4.5: should optimize bitwise operations)

Your message dated Sat, 25 Aug 2012 12:01:11 +0000
with message-id <E1T5F39-0008M9-JI@franck.debian.org>
and subject line Bug#675431: Removed package(s) from unstable
has caused the Debian Bug report #602785,
regarding gcc-4.5: should optimize bitwise operations
to be marked as done.

This means that you claim that the problem has been dealt with.
If this is not the case it is now your responsibility to reopen the
Bug report if necessary, and/or fix the problem forthwith.

(NB: If you are a system administrator and have no idea what this
message is talking about, this may indicate a serious mail system
misconfiguration somewhere. Please contact owner@bugs.debian.org
immediately.)


-- 
602785: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=602785
Debian Bug Tracking System
Contact owner@bugs.debian.org with problems
--- Begin Message --- 
Package: gcc-4.5
Version: 4.5.1-9
Severity: wishlist

The attached file (not preprocessed because of the macros) uses two
macros F and G.  F and G are completely equivalent[0].  As a result, r1
and r2 are guaranteed to be exactly equal always.  I would like gcc, at
level -O3, to basically optimize the code to "return 0;".  At the very
least, I would like G to be optimized to use one fewer instruction, like
F.

I realize that this may be difficult, and that's why I filed it as
wishlist.

[0] MD5 specifies G as a component function, but most implementers use F
instead because it uses one fewer instruction.

-- System Information:
Debian Release: squeeze/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (1, 'experimental')
Architecture: amd64 (x86_64)

Kernel: Linux 2.6.36-rc6-amd64 (SMP w/2 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages gcc-4.5 depends on:
ii  binutils              2.20.51.20100617-1 The GNU assembler, linker and bina
ii  cpp-4.5               4.5.1-9            The GNU C preprocessor
ii  gcc-4.5-base          4.5.1-9            The GNU Compiler Collection (base 
ii  libc6                 2.11.2-7           Embedded GNU C Library: Shared lib
ii  libcloog-ppl0         0.15.9-2           the Chunky Loop Generator (runtime
ii  libelfg0              0.8.13-1           an ELF object file access library
ii  libgcc1               1:4.5.1-9          GCC support library
ii  libgmp3c2             2:4.3.2+dfsg-1     Multiprecision arithmetic library
ii  libgmpxx4ldbl         2:4.3.2+dfsg-1     Multiprecision arithmetic library 
ii  libgomp1              4.5.1-9            GCC OpenMP (GOMP) support library
ii  libmpc2               0.8.2-1+b1         multiple precision complex floatin
ii  libmpfr4              3.0.0-2            multiple precision floating-point 
ii  libppl-c2             0.10.2-9           Parma Polyhedra Library (C interfa
ii  libppl7               0.10.2-9           Parma Polyhedra Library (runtime l
ii  zlib1g                1:1.2.3.4.dfsg-3   compression library - runtime

Versions of packages gcc-4.5 recommends:
ii  libc6-dev                     2.11.2-7   Embedded GNU C Library: Developmen

Versions of packages gcc-4.5 suggests:
pn  binutils-gold                 <none>     (no description available)
pn  gcc-4.5-doc                   <none>     (no description available)
pn  gcc-4.5-locales               <none>     (no description available)
ii  gcc-4.5-multilib              4.5.1-9    The GNU C compiler (multilib files
pn  libgcc1-dbg                   <none>     (no description available)
pn  libgomp1-dbg                  <none>     (no description available)
ii  libmudflap0-4.5-dev           4.5.1-9    GCC mudflap support libraries (dev
pn  libmudflap0-dbg               <none>     (no description available)

-- no debconf information

-- 
brian m. carlson / brian with sandals: Houston, Texas, US
+1 832 623 2791 | http://www.crustytoothpaste.net/~bmc | My opinion only
OpenPGP: RSA v4 4096b: 88AC E9B2 9196 305B A994 7552 F1BA 225C 0223 B187

#include <stdio.h>
#include <stdlib.h>
#include <time.h>

#define F(x, y, z) ((z)^((x)&((y)^(z))))
#define G(x, y, z) (((x)&(y))|((~(x))&(z)))

int main(void)
{
	unsigned x, y, z, r1, r2;

	srand(time(NULL));
	x = rand();
	y = rand();
	z = rand();
	r1 = F(x, y, z);
	r2 = G(x, y, z);
	if (r1 != r2)
		abort();
	return 0;
}

Attachment: signature.asc
Description: Digital signature


--- End Message ---
--- Begin Message --- 
Version: 4.5.4-1+rm

Dear submitter,

as the package gcc-4.5 has just been removed from the Debian archive
unstable we hereby close the associated bug reports.  We are sorry
that we couldn't deal with your issue properly.

For details on the removal, please see http://bugs.debian.org/675431

The version of this package that was in Debian prior to this removal
can still be found using http://snapshot.debian.org/.

This message was generated automatically; if you believe that there is
a problem with it please contact the archive administrators by mailing
ftpmaster@debian.org.

Debian distribution maintenance software
pp.
Luca Falavigna (the ftpmaster behind the curtain)

--- End Message ---
Reply to: