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Re: PING^3 for PR target/17836, PR c/10735, PR c++/16882, PR rtl-optimization/17860[3.4]


Paolo> This one at least seems wrong to me. Once more: unless Altivec is
on, Altivec vector types *won't have vector modes, but BLKmode*. The
"else if (ALTIVEC_VECTOR_MODE (mode))" won't trigger! That's why I did Why should parameters have stricter alignment if there is no SIMD
unit?

Because otherwise the non-Altivec ABI breaks depending on whether there is a SIMD unit or not.


	Also, while V2DI can be packed into an Altivec register and one
can apply a logical op, Altivec operations are not defined for those
types -- it is not part of the ABI.  There is no defined way to load and
store V2DI.  If you pun the type to load and store, you equally can pun
the type to perform logical ops.

The idea is that the middle-end can pun the types automatically, and use v4si insns to perform v2di ops. See tree-complex.c.


Paolo


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