rust/library/core
bors 039d887928 Auto merge of #119911 - NCGThompson:is-statically-known, r=oli-obk
Replacement of #114390: Add new intrinsic `is_var_statically_known` and optimize pow for powers of two

This adds a new intrinsic `is_val_statically_known` that lowers to [``@llvm.is.constant.*`](https://llvm.org/docs/LangRef.html#llvm-is-constant-intrinsic).` It also applies the intrinsic in the int_pow methods to recognize and optimize the idiom `2isize.pow(x)`. See #114390 for more discussion.

While I have extended the scope of the power of two optimization from #114390, I haven't added any new uses for the intrinsic. That can be done in later pull requests.

Note: When testing or using the library, be sure to use `--stage 1` or higher. Otherwise, the intrinsic will be a noop and the doctests will be skipped. If you are trying out edits, you may be interested in [`--keep-stage 0`](https://rustc-dev-guide.rust-lang.org/building/suggested.html#faster-builds-with---keep-stage).

Fixes #47234
Resolves #114390
`@Centri3`
2024-01-25 05:16:53 +00:00
..
benches Auto merge of #85528 - the8472:iter-markers, r=dtolnay 2024-01-21 11:17:46 +00:00
src Auto merge of #119911 - NCGThompson:is-statically-known, r=oli-obk 2024-01-25 05:16:53 +00:00
tests Revert "Auto merge of #118133 - Urgau:stabilize_trait_upcasting, r=WaffleLapkin" 2024-01-22 14:24:31 +00:00
Cargo.toml Update rand in the stdlib tests, and remove the getrandom feature from it 2023-01-04 14:52:41 -08:00