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Auto merge of #88308 - eddyb:cooked-layouts, r=nagisa

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Morph `layout_raw` query into `layout_of`.

Before this PR, `LayoutCx::layout_of` wrapped the `layout_raw` query, to:
* normalize the type, before attempting to compute the layout
* pass the layout to `record_layout_for_printing`, for `-Zprint-type-sizes`

Moving those two responsibilities into the query may reduce overhead (due to cached calls skipping those steps), but I want to do a perf run to know.

One of the changes I had to make was changing the return type of the query, to be able to both get out the type produced by normalizing inside the query *and* to match the signature of the old `TyCtxt::layout_of`. This change may be worse, perf-wise, so that's another reason I want to check.

r? `@nagisa` cc `@oli-obk`
This commit is contained in:
bors 2021-08-26 15:24:01 +00:00
commit 4b9f4b221b
9 changed files with 56 additions and 96 deletions
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compiler/rustc_target/src/abi/mod.rs
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@ -1139,7 +1139,7 @@ impl Layout {
/// to that obtained from `layout_of(ty)`, as we need to produce
/// layouts for which Rust types do not exist, such as enum variants
/// or synthetic fields of enums (i.e., discriminants) and fat pointers.
#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash, HashStable_Generic)]
pub struct TyAndLayout<'a, Ty> {
pub ty: Ty,
pub layout: &'a Layout,