[PATCH] D42732: [x86] Fix nasty bug in the x86 backend that is essentially impossible to hit from IR but creates a minefield for MI passes.

[Chandler Carruth via llvm-commits]

Thanks Rafael, landing with those additional checks.

On Wed, Feb 7, 2018 at 3:28 PM Rafael Avila de Espindola via llvm-commits <
llvm-commits at lists.llvm.org> wrote:

> Chandler Carruth via Phabricator via llvm-commits
> <llvm-commits at lists.llvm.org> writes:
>
>
> > +# CHECK-LABEL: or:
> > +name: or
> > +alignment: 4
> > +tracksRegLiveness: true
> > +registers:
> > +  - { id: 0, class: gr64 }
> > +  - { id: 1, class: gr64 }
> > +  - { id: 2, class: gr64 }
> > +  - { id: 3, class: gr64 }
> > +  - { id: 4, class: gr32 }
> > +body: |
> > +  bb.0.entry:
> > +    %0:gr64 = MOV64rm $rip, 1, $noreg, @x, $noreg :: (load 8)
> > +    %1:gr64 = OR64ri8 %0, 7, implicit-def dead $eflags
> > +    %2:gr64 = MOV64rm $rip, 1, $noreg, target-flags(x86-gottpoff) @i,
> $noreg :: (load 8)
> > +    %3:gr64 = OR64rr %2, %1, implicit-def dead $eflags
> > +  ; CHECK-NOT: orq {{.*}}GOTTPOFF{{.*}}
>
> You probably also want to CHECK what is actually produced.
>
> > +    %4:gr32 = MOV32rm killed %3, 1, $noreg, 0, $fs :: (load 4)
> > +    $eax = COPY %4
> > +    RET 0, $eax
> > +
> > +...
> > +---
> > +# CHECK-LABEL: and:
> > +name: and
> > +alignment: 4
> > +tracksRegLiveness: true
> > +registers:
> > +  - { id: 0, class: gr64 }
> > +  - { id: 1, class: gr64 }
> > +  - { id: 2, class: gr64 }
> > +  - { id: 3, class: gr64 }
> > +  - { id: 4, class: gr32 }
> > +body: |
> > +  bb.0.entry:
> > +    %0:gr64 = MOV64rm $rip, 1, $noreg, @x, $noreg :: (load 8)
> > +    %1:gr64 = OR64ri8 %0, 7, implicit-def dead $eflags
> > +    %2:gr64 = MOV64rm $rip, 1, $noreg, target-flags(x86-gottpoff) @i,
> $noreg :: (load 8)
> > +    %3:gr64 = AND64rr %2, %1, implicit-def dead $eflags
> > +  ; CHECK-NOT: andq {{.*}}GOTTPOFF{{.*}}
>
> In here too.
>
>
> LGTM with that.
>
> Cheers,
> Rafael
> _______________________________________________
> llvm-commits mailing list
> llvm-commits at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-commits
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20180207/ead7b31b/attachment.html>