On Wed, Apr 25, 2012 at 9:14 PM, Jakub Jelinek <ja...@redhat.com> wrote:
> We have a splitter for reg1 = reg2 & 0xffffffff, but only if regnums > are different. But movl %edi, %edi is a cheaper variant of > andq $0xffffffff, %rdi even with the same register and doesn't clobber > flags, so this patch attempts to expand it as a zero extension early. > > Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? > > 2012-04-25 Jakub Jelinek <ja...@redhat.com> > > PR target/53110 > * config/i386/i386.md (and<mode>3): For andq $0xffffffff, reg > instead expand it as zero extension. Perhaps we can go all the way and also convert ANDs with $0xff and $0xffff to relevant zero_extend patterns, like in the referred splitter. Uros.
