[Bug target/111252] LoongArch: Suboptimal code for (a & ~mask) | (b & mask) where mask is a constant with value ((1 << n) - 1) << m

[xry111 at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111252

--- Comment #5 from Xi Ruoyao <xry111 at gcc dot gnu.org> ---
(In reply to Xi Ruoyao from comment #4)

> Hmm, this seems a separate issue.  The compiler knows to optimize (a & mask)
> if mask is ((1 << a) - 1) << b iff a + b = 32 or b = 0, but not for any

I mean "32 or 64".

> other masks even if it's "expensive" to materialize the mask: