[Bug rtl-optimization/37262] Two branches of the same condition being emitted

["msebor at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=37262

--- Comment #7 from Martin Sebor <msebor at gcc dot gnu.org> ---
Yes, sorry, I meant to say "still there at -O1" because that's the optimization
level mentioned in comment #1.  (I had to guess at the level based on that.  I
also accidentally used -m32 when the target is powerpc64, probably because of
all the other old 32-bit powerpc bugs I've been looking at.)

The -O2 code for -m32 doesn't have the duplicate branch, though it does nicely
show the other unnecessary branches:

$ /build/gcc-5.x/gcc/xgcc -B /build/gcc-5.x/gcc -O2 -S -Wall -Wextra -Wpedantic
-m32 -o/dev/stdout t.c
...
_bfd_xcoff_canonicalize_dynamic_reloc:
        cmpwi 7,3,0
        bnelr 7
        cmplwi 7,4,2
        bgtlr 7
        bnelr 7
        b _bfd_abort

...and for -m64:

.L._bfd_xcoff_canonicalize_dynamic_reloc:
        cmpldi 7,3,2
        bgt 7,.L2
        beq 7,.L7
.L2:
        blr
        .p2align 4,,15
.L7:
        mflr 0
        std 0,16(1)
        stdu 1,-112(1)
        bl _bfd_abort
        nop
        addi 1,1,112
        ld 0,16(1)
        mtlr 0
        blr