PATCH: [4.1/4.2 Regression]: Miscompiled FORTRAN program

[Jim Wilson]

H. J. Lu wrote:
>         PR rtl-optimization/25603
>         * reload.c (reg_inc_found_and_valid_p): New.
> 	(regno_clobbered_p): Handle REG_INC as 25603 workaround.

I don't believe this is safe.  If you look at the uses of 
regno_clobbered_p in reload.c, the comments clearly indicate that we are 
looking for registers used in clobbers.  So unconditionally adding code 
that handles REG_INC notes will break these uses.  You have to add the 
REG_INC support the same way that the sets support was added, by adding 
another argument (or reusing the sets argument), and then modifying the 
one place we know is broken (choose_reload_regs) to use the new argument 
(or new sets argument value).
-- 
Jim Wilson, GNU Tools Support, http://www.specifix.com