[Bug rtl-optimization/57347] [4.8/4.9 Regression] wrong code for bitfield on x86_64-linux at -Os and above

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57347

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |jamborm at gcc dot gnu.org

--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
I don't find code in http://gcc.gnu.org/ml/gcc-patches/2012-11/msg00460.html to
handle bitfields, the comment talks about punting on them, but I couldn't find
anything that would try to punt.
ipa_load_from_parm_agg_1 seems to return just the bit offset (which is then
compared to the offsets in aggval chain), but not the access bitsize (if aggval
is guaranteed to contain values for all fields, then perhaps with bitsize it
would be enough to look for all v where v->offset is in [offset,
offset+bitsize)
and combine all those values together - is v->value always constant?).