[LLVMdev] Generating movq2dq using IRBuilder

[Dan Gohman]

On Jul 31, 2008, at 7:22 AM, Nicolas Capens wrote:

> In the same breath I’d also like to kindly ask if someone could have  
> a look at the reverse operations, namely trunk from 128 to 64 bit  
> using movdq2q, and 128 to 32 and 64 to 32 using movd. This also  
> seems related to Bug 2585. Thanks again.

The operations you're describing can be represented as insertelement
and extractelement in LLVM IR.

I don't know of anyone actively working on MMX tuning for LLVM, so
if you'd like to see it improve, consider yourself encouraged to
get involved directly :-).

Dan