[Bug rtl-optimization/64304] AArch64 miscompilation with -mgeneral-regs-only

[jiwang at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64304

Jiong Wang <jiwang at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2015-01-06
     Ever confirmed|0                           |1

--- Comment #2 from Jiong Wang <jiwang at gcc dot gnu.org> ---
a quick looks shows it's related with SHIFT_COUNT_TRUNCATED.

looks like generic code, especially combine pass, is with wrong usage of
SHIFT_COUNT_TRUNCATED in some situations.