incr.comp.: Verify stability of incr. comp. hashes and clean up various other things.
The main contribution of this PR is that it adds the `-Z incremental-verify-ich` functionality. Normally, when the red-green tracking system determines that a certain query result has not changed, it does not re-compute the incr. comp. hash (ICH) for that query result because that hash is already known. `-Z incremental-verify-ich` tells the compiler to re-hash the query result and compare the new hash against the cached hash. This is a rather thorough way of
- testing hashing implementation stability,
- finding missing `[input]` annotations on `DepNodes`, and
- finding missing read-edges,
since both a missed read and a missing `[input]` annotation can lead to something being marked as green instead of red and thus will have a different hash than it should have.
Case in point, implementing this verification logic and activating it for all `src/test/incremental` tests has revealed several such oversights, all of which are fixed in this PR.
r? @nikomatsakis
DefaultImpl is a highly confusing name for what we now call auto impls,
as in `impl Send for ..`. The name auto impl is not formally decided
but for sanity anything is better than `DefaultImpl` which refers
neither to `default impl` nor to `impl Default`.
incr.comp.: Implement compiler diagnostic persistence.
This PR implements storing and loading diagnostics that the compiler generates and thus allows for emitting warnings during incremental compilation without actually re-evaluating the thing the warning originally came from. It also lays some groundwork for storing and loading type information and MIR in the incr. comp. cache.
~~It is still work in progress:~~
- ~~There's still some documentation to be added.~~
- ~~The way anonymous queries are handled might lead to duplicated emissions of warnings. Not sure if there is a better way or how frequent such duplication would be in practice.~~
Diagnostic message duplication is addressed separately in #45519.
r? @nikomatsakis
Create NormalizeTy query
As part of the effort to solve #44891, I've created the normalize_ty query.
As outlined in the issue this meant:
- renamed `normalize_associated_type()` to `normalize_associated_type_in()`
- created the `normalize_ty` query
- substituted the use of memoize with the query
This PR is not ready. While running tests, one of the incremental ones failed. [This](https://pastebin.com/vGhH6bv6) is the error I got.
This commit moves compression of the bytecode from the `link` module to the
`write` module, namely allowing it to be (a) cached by incremental compilation
and (b) produced in parallel. The parallelization may show up as some nice wins
during normal compilation and the caching in incremental mode should be
beneficial for incremental compiles! (no more need to recompress the entire
crate's bitcode on all builds)
remove or encapsulate the remaining non-query data in tcx
I wound up removing the existing cache around inhabitedness since it didn't seem to be adding much value. I reworked const rvalue promotion, but not that much (i.e., I did not split the computation into bits, as @eddyb had tossed out as a suggestion). But it's now demand driven, at least.
cc @michaelwoerister -- see the `forbid_reads` change in last commit
r? @eddyb -- since the trickiest of this PR is the work on const rvalue promotion
cc #44137
Queryify Vtable methods
This query might come with a downside: It converts an iterator to a Vec, which may increase the working set of rustc on programs that use many many traits (I think that's where this is used).
Incremental compilation auto assert (with except)
cc @michaelwoerister
bors merged part 1, so this is a WIP of part 2 of #45009 -- auto asserting DepNodes depending on the type of node rustc_clean/dirty is attached to
Framework:
- [x] finish auto-detection for specified DepNodes
- [x] finish auto-detection for remaining DepNodes
Test Refactors:
- [x] consts.rs
- [x] enum_constructors.rs
- [x] extern_mods.rs
- [x] inherent_impls.rs
- [x] statics.rs
- [x] struct_constructors.rs
- ~~**BLOCKED** trait_defs.rs, see FIXME~~
- ~~**BLOCKED** trait_impls.rs~~
- [x] type_defs.rs
- [x] enum_defs.rs
This adds auto-assertion to `rustc_clean/dirty` and also implements
more comprehensive testing for
- src/test/incremental/hashes/enum_constructors.rs
- src/test/incremental/hashes/enum_defs.rs
- src/test/incremental/hashes/extern_mods.rs
- src/test/incremental/hashes/inherent_impls.rs
- src/test/incremental/hashes/statics.rs
- src/test/incremental/hashes/struct_constructors.rs
- src/test/incremental/hashes/type_defs.rs
trait_defs.rs and trait_impl.rs are blocked on a hard to triage
compiler ICE (at least hard for a newbie like me) having to do
with some DepNodes not getting computed for traits.
A FIXME has been added in the source to reflect this continued
work.
groundwork for rustc_clean/dirty improvements
This is a WIP PR that needs mentoring from @michaelwoerister.
There are several TODOs but no outstanding questions (except for the main one -- **is this the right approach?**)
This is the plumbing for supporing groups in `rustc_clean(labels="...")`, as well as supporting an `except="..."` which will remove the excepted labels in the "clean" check and then assert that they are dirty (this is still TODO).
See the code TODO's and example comments for a rough design.
I'd like to know if this is the design you would like to do, and then I can go about actually filling out the groups and implementing the remaining logic.
