On Thu, Oct 29, 2015 at 12:52 PM, Segher Boessenkool
<seg...@kernel.crashing.org> wrote:
> The PIC reg (r30) needs to be saved whenever the prologue sets it up,
> not just if it is used elsewhere in the function. Without this patch
> the prologue for such a function will modify r30 without saving it
> first, leading to disaster back in its callers. This happened in the
> testsuite for -m32 libgfortran and libstdc++, bootstrapped with -mlra,
> many hundred times.
>
> Tested on powerpc64-linux, with LRA enabled by default (so that the
> target libraries are built with -mlra, the case that failed before
> this patch),
> {-m32/-mlra,-m32/-mno-lra,-m32/-mpowerpc64,-m64/-mlra,-m64/-mno-lra}.
> With this and the previous LRA patch there now are no differences
> between -mlra and -mno-lra testsuite runs (on big-endian power7, gcc110).
>
> Is this okay for trunk?
>
>
> Segher
>
>
> 2015-10-29 Segher Boessenkool <seg...@kernel.crashing.org>
>
> * config/rs6000/rs6000.c (rs6000_reg_live_or_pic_offset_p): Move this
> function earlier in the file.
> (first_reg_to_save): Use rs6000_reg_live_or_pic_offset_p instead of
> df_regs_ever_live_p.
Good catch!
Thanks, David
