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[Bug rtl-optimization/29589] incorrect conversion of (ior (ashiftrt (plus ...))) in combine.c



------- Comment #1 from dje at transmeta dot com  2006-10-25 02:23 -------
Re: "We think may be what wanted is:" ...

That's just off the cuff speculation.  The curious things are:

- op1 is shifted outside the mode of the operation (0x3c << 31) (HOST_WIDE_INT
is 64 bits) and this value is the value AND'd with the result of nonzero_bits.

- nonzero_bits returns bits that may be one, not bits that are one, so it's not
clear this optimization is valid regardless of anything else


-- 

dje at transmeta dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|incorrect conversion of (ior|incorrect conversion of (ior
                   |(ashiftrt (plus ...))) in   |(ashiftrt (plus ...))) in
                   |combine.c                   |combine.c


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29589


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