------- Comment #2 from bonzini at gnu dot org 2009-07-14 10:51 -------
Here combine simplifies the zero extension from
(lshiftrt:SI (ashift:SI (subreg:SI (reg:QI 138) 0)
(const_int 24 [0x18]))
(const_int 24 [0x18]))
to (ne:SI (subreg:SI (reg:QI 138)). From there it cannot derive anymore that
nonzero_bits of the operand is 1 and thus the NE is redundant.
But shouldn't the subreg actually be a ZERO_EXTEND?
--
bonzini at gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |rsandifo at gcc dot gnu dot
| |org
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39715
