[Bug target/87601] Missed opportunity for flag reuse and macro-op fusion on x86

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87601

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
        sub     rsi, 1
        test    esi, esi
        jne     .L3

To
        sub     rsi, 1
        jne     .L3

Is not the same, the first is a 64bit subtract followed by a 32bit compare. in
the 2nd case, you have a 64bit subtract with the 64bit compare happening.