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Re: [Patch][PR91504] Inlining misses some logical operation folding
On Mon, Aug 26, 2019 at 02:04:25PM +0200, Richard Biener wrote:
> On Mon, 26 Aug 2019, kamlesh kumar wrote:
> > +/* (~a & b) ^ a --> (a | b) */
> > +(simplify
> > + (bit_xor:c (bit_and:cs (bit_not @0) @1) @0)
> > + (bit_ior @0 @1))
> > +
>
> Are you sure?
>
> (~1804289383 & 846930886) ^ 1804289383 != 1804289383 | 846930886
Both are hex 7bfb67e7.
a|b = a|(b&~a) = a^(b&~a)
> if ((~a & b) ^ a != a | b)
!= has higher precedence than ^ and | (and &).
Segher