Oh, yes...strange attributes #0 = { noinline nounwind optnone uwtable "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+fxsr,+mmx,+sse,+sse2,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" } How this can be avoided? it is always so after clang -s -emit-llvm 2017-07-05 16:49 GMT+02:00 Hal Finkel <hfinkel at anl.gov>:> > On 07/04/2017 04:25 AM, Anastasiya Ruzhanskaya via llvm-dev wrote: > > Hello, > I am developing now a compiler, based on llvm infrastructure, so I am > building my own sequence of llvm passes with some adjustable options. > > I can't find really clear info about some cases, so maybe you can help, > and write: > > 0) Why I should always delete attributes before applying optimizations > with opt command? With attributes specified no optimization can be applied. > > > You definitely shouldn't delete attributes in general. Does your attribute > set include optnone? > > -Hal > > > Where I can get real benefit from: > 1) Constant Hoisting > -only when we have some large reusable constants in program? > 2) argpomotion > - this option does not always replace all my args by reerence with values, > when I specify it. > > > _______________________________________________ > LLVM Developers mailing listllvm-dev at lists.llvm.orghttp://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev > > > -- > Hal Finkel > Lead, Compiler Technology and Programming Languages > Leadership Computing Facility > Argonne National Laboratory > >-------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20170705/6a9fd7c3/attachment.html>
On 07/05/2017 09:58 AM, Anastasiya Ruzhanskaya wrote:> Oh, yes...strange > |attributes #0 = { noinline nounwind optnone uwtable > "correctly-rounded-divide-sqrt-fp-math"="false" > "disable-tail-calls"="false" "less-precise-fpmad"="false" > "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" > "no-infs-fp-math"="false" "no-jump-tables"="false" > "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" > "no-trapping-math"="false" "stack-protector-buffer-size"="8" > "target-cpu"="x86-64" "target-features"="+fxsr,+mmx,+sse,+sse2,+x87" > "unsafe-fp-math"="false" "use-soft-float"="false" } > > | > |How this can be avoided? it is always so after clang -s -emit-llvm > |This is because clang defaults to -O0, and in that mode, does not produce IR that is intended to be optimized. You probably want to do: clang -S -emit-llvm -O3 -mllvm -disable-llvm-optzns to get out the unoptimized IR. -Hal> > > > 2017-07-05 16:49 GMT+02:00 Hal Finkel <hfinkel at anl.gov > <mailto:hfinkel at anl.gov>>: > > > On 07/04/2017 04:25 AM, Anastasiya Ruzhanskaya via llvm-dev wrote: >> Hello, >> I am developing now a compiler, based on llvm infrastructure, so >> I am building my own sequence of llvm passes with some adjustable >> options. >> >> I can't find really clear info about some cases, so maybe you can >> help, and write: >> >> 0) Why I should always delete attributes before applying >> optimizations with opt command? With attributes specified no >> optimization can be applied. > > You definitely shouldn't delete attributes in general. Does your > attribute set include optnone? > > -Hal > >> >> Where I can get real benefit from: >> 1) Constant Hoisting >> -only when we have some large reusable constants in program? >> 2) argpomotion >> - this option does not always replace all my args by reerence >> with values, when I specify it. >> >> >> _______________________________________________ >> LLVM Developers mailing list >> llvm-dev at lists.llvm.org <mailto:llvm-dev at lists.llvm.org> >> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev >> <http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev> > > -- > Hal Finkel > Lead, Compiler Technology and Programming Languages > Leadership Computing Facility > Argonne National Laboratory >-- Hal Finkel Lead, Compiler Technology and Programming Languages Leadership Computing Facility Argonne National Laboratory -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20170705/8ac37e52/attachment.html>
Great, thank you for your help! 2017-07-05 17:06 GMT+02:00 Hal Finkel <hfinkel at anl.gov>:> > On 07/05/2017 09:58 AM, Anastasiya Ruzhanskaya wrote: > > Oh, yes...strange > attributes #0 = { noinline nounwind optnone uwtable > "correctly-rounded-divide-sqrt-fp-math"="false" > "disable-tail-calls"="false" "less-precise-fpmad"="false" > "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" > "no-infs-fp-math"="false" "no-jump-tables"="false" > "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" > "no-trapping-math"="false" "stack-protector-buffer-size"="8" > "target-cpu"="x86-64" "target-features"="+fxsr,+mmx,+sse,+sse2,+x87" > "unsafe-fp-math"="false" "use-soft-float"="false" } > > How this can be avoided? it is always so after clang -s -emit-llvm > > > This is because clang defaults to -O0, and in that mode, does not produce > IR that is intended to be optimized. You probably want to do: > > clang -S -emit-llvm -O3 -mllvm -disable-llvm-optzns > > to get out the unoptimized IR. > > -Hal > > > > > > 2017-07-05 16:49 GMT+02:00 Hal Finkel <hfinkel at anl.gov>: > >> >> On 07/04/2017 04:25 AM, Anastasiya Ruzhanskaya via llvm-dev wrote: >> >> Hello, >> I am developing now a compiler, based on llvm infrastructure, so I am >> building my own sequence of llvm passes with some adjustable options. >> >> I can't find really clear info about some cases, so maybe you can help, >> and write: >> >> 0) Why I should always delete attributes before applying optimizations >> with opt command? With attributes specified no optimization can be applied. >> >> >> You definitely shouldn't delete attributes in general. Does your >> attribute set include optnone? >> >> -Hal >> >> >> Where I can get real benefit from: >> 1) Constant Hoisting >> -only when we have some large reusable constants in program? >> 2) argpomotion >> - this option does not always replace all my args by reerence with >> values, when I specify it. >> >> >> _______________________________________________ >> LLVM Developers mailing listllvm-dev at lists.llvm.orghttp://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev >> >> -- >> Hal Finkel >> Lead, Compiler Technology and Programming Languages >> Leadership Computing Facility >> Argonne National Laboratory >> >> -- > Hal Finkel > Lead, Compiler Technology and Programming Languages > Leadership Computing Facility > Argonne National Laboratory > >-------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20170706/63c8045c/attachment.html>