bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

Rollup merge of #130715 - compiler-errors:mir-build-const-eval, r=BoxyUwU

Browse source 
Replace calls to `ty::Const::{try_}eval` in mir build/pattern analysis

We normalize consts in writeback: #130645. This means that consts are gonna be as normalized as they're ever gonna get in MIR building and pattern analysis. Therefore we can just use `try_to_target_usize` rather than calling `eval_target_usize`.

Regarding the `.expect` calls, I'm not totally certain whether they're correct given rigid unevaluated consts. But this PR shouldn't make *more* ICEs occur; we may have to squash these ICEs when mGCE comes around, tho 😺
This commit is contained in:
Matthias Krüger 2024-09-23 06:45:36 +02:00 • committed by GitHub
commit 0e08d7002b
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
4 changed files with 17 additions and 7 deletions
Download patch file Download diff file Expand all files Collapse all files

11
compiler/rustc_pattern_analysis/src/rustc.rs
View file

@ -352,7 +352,7 @@ impl<'p, 'tcx: 'p> RustcPatCtxt<'p, 'tcx> {
ty::Array(sub_ty, len) => {
// We treat arrays of a constant but unknown length like slices.
ConstructorSet::Slice {
array_len: len.try_eval_target_usize(cx.tcx, cx.param_env).map(|l| l as usize),
array_len: len.try_to_target_usize(cx.tcx).map(|l| l as usize),
subtype_is_empty: cx.is_uninhabited(*sub_ty),
}
}
@ -685,9 +685,12 @@ impl<'p, 'tcx: 'p> RustcPatCtxt<'p, 'tcx> {
}
PatKind::Array { prefix, slice, suffix } | PatKind::Slice { prefix, slice, suffix } => {
let array_len = match ty.kind() {
ty::Array(_, length) => {
Some(length.eval_target_usize(cx.tcx, cx.param_env) as usize)
}
ty::Array(_, length) => Some(
length
.try_to_target_usize(cx.tcx)
.expect("expected len of array pat to be definite")
as usize,
),
ty::Slice(_) => None,
_ => span_bug!(pat.span, "bad ty {} for slice pattern", ty.inner()),
};