> -----Original Message----- > From: Jeff Law [mailto:l...@redhat.com] > Sent: Thursday, March 5, 2020 11:37 PM > To: Yangfei (Felix) <felix.y...@huawei.com>; gcc-patches@gcc.gnu.org > Cc: Zhanghaijian (A) <z.zhanghaij...@huawei.com> > Subject: Re: [PATCH PR94026] combine missed opportunity to simplify > comparisons with zero > > On Wed, 2020-03-04 at 08:39 +0000, Yangfei (Felix) wrote: > > Hi, > > > > This is a simple fix for PR94026. > > With this fix, combine will try make an extraction if we are in a > > equality comparison and this is an AND > > with a constant which is power of two minus one. Shift here should > > be an constant. For example, combine > > will transform (compare (and (lshiftrt x 8) 6) 0) to (compare > > (zero_extract (x 2 9)) 0). > > > > Added one test case for this. Bootstrap and tested on both x86_64 > > and > > aarch64 Linux platform. > > Any suggestion? > > > > Thanks, > > Felix > > > > gcc: > > +2020-03-04 Felix Yang <felix.y...@huawei.com> > > + > > + PR rtl-optimization/94026 > > + * combine.c (make_compound_operation_int): Make an extraction > > + if we are in a equality comparison and this is an AND with a > > + constant which is power of two minus one. > > + > > > > gcc/testsuite: > > +2020-03-04 Felix Yang <felix.y...@huawei.com> > > + > > + PR rtl-optimization/94026 > > + * gcc.dg/pr94026.c: New test. > Just a note. We're in stage4 of our development cycle, meaning we focus on > regression bugfixes. I've queued this for evaluation in gcc-11. > jeff
Sure, this is intended for 11. Thanks for doing that : - ) Best regards, Felix
