SSE4a
- [ ] EXTRQ/​INSERTQ Combined mask-shift instructions.
- [ ] MOVNTSD/​MOVNTSS Scalar streaming store instructions.

Header is [<ammintrin.h>](https://gcc.gnu.org/git/?p=gcc.git;a=blob;f=gcc/config/i386/ammintrin.h;h=b94731a9e2ca64529189a3ed8b16a5147c27c652;hb=HEAD)