Miscompilation of asm("{cntlz|cntlzw} %0, %1" ...) on PowerPC

[isanbard]

Bugzilla Link	1095
Resolution	FIXED
Resolved on	Feb 22, 2010 12:53
Version	trunk
OS	MacOS X

Extended Description

On my PowerBook G4, compiling this program:

#include <stdio.h>

int main()
{
unsigned long int ctz_x = 0x0000f000;
unsigned long int ctz_c;

asm("{cntlz|cntlzw} %0,%1"
: "=r" (ctz_c)
: "r" (ctz_x & -ctz_x));

printf("ctz_c == %d\n", ctz_c);
return 0;
}

results in the use of the mnemonic "cntlz" instead of "cntlzw". This produces an error when trying to
assemble the program:

cntlzw_miscompile.s:25:Invalid mnemonic 'cntlz'

GCC outputs "cntlzw" instead.

-bw

[isanbard]

This was found when trying to compile "gmp".

[isanbard]

Fixed with:

http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20070115/042747.html
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20070115/042748.html
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20070115/042749.html
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20070115/042750.html
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20070115/042751.html
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20070115/042752.html

-bw