Auto merge of #117444 - matthiaskrgr:rollup-43s0spc, r=matthiaskrgr

Rollup of 5 pull requests

Successful merges:

 - #116267 (Some codegen cleanups around SIMD checks)
 - #116712 (When encountering unclosed delimiters during lexing, check for diff markers)
 - #117416 (Also consider TAIT to be uncomputable if the MIR body is tainted)
 - #117421 (coverage: Replace impossible `coverage::Error` with assertions)
 - #117438 (Do not ICE on constant evaluation failure in GVN.)

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

Author: bors