-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On Wed, 23 Oct 2002 17:36:14 -0400, Jakub Jelinek wrote:
> > A test using a simple C source file: > > > > -march=i386 -mcpu=i586 and -march=i586 -mcpu=i586 > > were the same. > > > > -march=i386 -mcpu=i586 and -march=i386 -mcpu=i686 > > had a lot of differences. The instruction mix was very different. > > > > -march=i386 -mcpu=i586 and -march=i386 -mcpu=athlon > > Very different to. > > > > -march=i386 -mcpu=i686 was the same as -march=i386 -mcpu=athlon > > Most interesting to me, > > The mix is different. > > > > example > > i686 athlon > > movl -24(%edp), %edx andl -24(%edp), %eax > > andl %edx, %eax > > > > > > movl %eax, %edx imull $100, %eax, %edx > > movl %edx, %eax > > sall $2, %eax > > addl %edx, %eax > > leal 0(,%eax,4), %edx > > addl %edx, %eax > > leal 0(,%eax,4), %edx > > Do you have testcase and exact options for this? > $edx = 100*$eax is with -O2 -mcpu=i686: > leal (%eax,%eax,4), %edx > leal (%edx,%edx,4), %edx > sall $2, %edx > for me. I think Thomas didn't use -O2. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.6 (GNU/Linux) iD8DBQE9tyhV0iMVcrivHFQRAgCwAJ9P2Qd4iSy8yAGTCvvxiGr0j20F5gCdGodg O372/rBciVf8va/b9mbTZGA= =l1r1 -----END PGP SIGNATURE-----
