[Bug target/51244] SH Target: Inefficient conditional branch

[oleg.endo@t-online.de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51244

--- Comment #5 from Oleg Endo <oleg.endo@t-online.de> 2011-12-28 02:44:05 UTC ---
(In reply to comment #2)
> (In reply to comment #1)
> > 
> > BTW, OT, (a != b || a != c) ? b : c could be reduced to b, I think.
> > 
> 
> Yes, very much so.
> It is reduced to "return b" for -m2, -m2e, -m2a, -m3, -m3e
> but not for -m1 and -m4*.

This seems to be due to the following in sh.h:

#define BRANCH_COST(speed_p, predictable_p) \
    (TARGET_SH5 ? 1 : ! TARGET_SH2 || TARGET_HARD_SH4 ? 2 : 1)