Richard, Can you please commit this patch for me? I don't have write access yet, I'm still working on getting copyright assignment/disclaimer signed by my employer.
Thanks, Eugene -----Original Message----- From: Richard Biener <richard.guent...@gmail.com> Sent: Friday, January 15, 2021 3:55 AM To: Eugene Rozenfeld <eugene.rozenf...@microsoft.com> Cc: gabrav...@gmail.com; ja...@gcc.gnu.org; gcc-patches@gcc.gnu.org Subject: Re: [EXTERNAL] Re: [PATCH][tree-optimization]Optimize combination of comparisons to dec+compare On Thu, Jan 14, 2021 at 10:04 PM Eugene Rozenfeld <eugene.rozenf...@microsoft.com> wrote: > > I got more feedback for the patch from Gabriel Ravier and Jakub Jelinek in > https://nam06.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgcc.gnu.org%2Fbugzilla%2Fshow_bug.cgi%3Fid%3D96674&data=04%7C01%7CEugene.Rozenfeld%40microsoft.com%7Cf4b1e41de6b4469fd3bb08d8b94c5a20%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C637463084866262315%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=%2Fc77uS%2BNlNGmXwOmK729BByEW0VDiq1HEe8BA7DpI30%3D&reserved=0 > and re-worked it accordingly. > > The changes from the previous patch are: > 1. Switched the tests to use __attribute__((noipa)) instead of > __attribute__((noinline)) . > 2. Fixed a type in the pattern comment. > 3. Added :c for top-level bit_ior expression. > 4. Added :s for the subexpressions. > 5. Added a pattern for the negated expression: > x >= y && y != XXX_MIN --> x > y - 1 > and the corresponding tests. > > The new patch is attached. OK. Thanks, Richard. > Eugene > > -----Original Message----- > From: Richard Biener <richard.guent...@gmail.com> > Sent: Tuesday, January 5, 2021 4:21 AM > To: Eugene Rozenfeld <eugene.rozenf...@microsoft.com> > Cc: gcc-patches@gcc.gnu.org > Subject: [EXTERNAL] Re: [PATCH][tree-optimization]Optimize combination > of comparisons to dec+compare > > On Mon, Jan 4, 2021 at 9:50 PM Eugene Rozenfeld > <eugene.rozenf...@microsoft.com> wrote: > > > > Ping. > > > > -----Original Message----- > > From: Eugene Rozenfeld > > Sent: Tuesday, December 22, 2020 3:01 PM > > To: Richard Biener <richard.guent...@gmail.com>; > > gcc-patches@gcc.gnu.org > > Subject: RE: Optimize combination of comparisons to dec+compare > > > > Re-sending my question and re-attaching the patch. > > > > Richard, can you please clarify your feedback? > > Hmm, OK. > > The patch is OK. > > Thanks, > Richard. > > > > Thanks, > > > > Eugene > > > > -----Original Message----- > > From: Gcc-patches <gcc-patches-boun...@gcc.gnu.org> On Behalf Of > > Eugene Rozenfeld via Gcc-patches > > Sent: Tuesday, December 15, 2020 2:06 PM > > To: Richard Biener <richard.guent...@gmail.com> > > Cc: gcc-patches@gcc.gnu.org > > Subject: [EXTERNAL] Re: Optimize combination of comparisons to > > dec+compare > > > > Richard, > > > > > Do we already handle x < y || x <= CST to x <= y - CST? > > > > That is an invalid transformation: e.g., consider x=3, y=4, CST=2. > > Can you please clarify? > > > > Thanks, > > > > Eugene > > > > -----Original Message----- > > From: Richard Biener <richard.guent...@gmail.com> > > Sent: Thursday, December 10, 2020 12:21 AM > > To: Eugene Rozenfeld <eugene.rozenf...@microsoft.com> > > Cc: gcc-patches@gcc.gnu.org > > Subject: Re: Optimize combination of comparisons to dec+compare > > > > On Thu, Dec 10, 2020 at 1:52 AM Eugene Rozenfeld via Gcc-patches > > <gcc-patches@gcc.gnu.org> wrote: > > > > > > This patch adds a pattern for optimizing x < y || x == XXX_MIN to > > > x <= > > > y-1 if y is an integer with TYPE_OVERFLOW_WRAPS. > > > > Do we already handle x < y || x <= CST to x <= y - CST? > > That is, the XXX_MIN case is just a special-case of generic anti-range > > testing? For anti-range testing with signed types we pun to unsigned when > > possible. > > > > > This fixes pr96674. > > > > > > Tested on x86_64-pc-linux-gnu. > > > > > > For this function > > > > > > bool f(unsigned a, unsigned b) > > > { > > > return (b == 0) | (a < b); > > > } > > > > > > the code without the patch is > > > > > > test esi,esi > > > sete al > > > cmp esi,edi > > > seta dl > > > or eax,edx > > > ret > > > > > > the code with the patch is > > > > > > sub esi,0x1 > > > cmp esi,edi > > > setae al > > > ret > > > > > > Eugene > > > > > > gcc/ > > > PR tree-optimization/96674 > > > * match.pd: New pattern x < y || x == XXX_MIN --> x <= y - 1 > > > > > > gcc/testsuite > > > * gcc.dg/pr96674.c: New test. > > >
