Auto merge of #125892 - workingjubilee:rollup-gytt1q7, r=workingjubilee

Rollup of 3 pull requests

Successful merges:

 - #125311 (Make repr(packed) vectors work with SIMD intrinsics)
 - #125849 (Migrate `run-make/emit-named-files` to `rmake.rs`)
 - #125851 (Add some more specific checks to the MIR validator)

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors