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[Bug target/67712] [SH] __builtin_strncmp causes code bloat


https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67712

Oleg Endo <olegendo at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2017-08-16
     Ever confirmed|0                           |1

--- Comment #4 from Oleg Endo <olegendo at gcc dot gnu.org> ---
(In reply to Joseph S. Myers from comment #3)
> The patch committed limits the unrolling, but not necessarily as much as
> desirable (given the bug is about an 8-byte case and the limit is 32 bytes).

The unrolled byte checking tail doesn't seem to make sense at all.  It will run
for 4 bytes at most, because the 4-byte loop (at L5 with cmp/str in the above
example) will have already determined that there is a byte mismatch in one of
the 4 bytes.

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