generate fewer basic blocks for variant switches
CC #33567
Adds a new field to TestKind::Switch that tracks the variants that are actually matched against. The other candidates target a common "otherwise" block.
This commit attempts to bring our prepends to PATH on Windows when loading
plugins because we've been seeing quite a few issues with failing to spawn a
process on Windows, the leading theory of which is that PATH is too large as a
result of this. Currently this is mostly a stab in the dark as it's not
confirmed to actually fix the problem, but it's probably not a bad change to
have anyway!
cc #33844Closes#17360
Fix a regression in the configuration folder
This fixes#34028, a regression caused by #33706 in which unconfigured impl items generated by a macro in an impl item position are not removed.
r? @nrc
Projection cache and better warnings for #32330
This PR does three things:
- it lays the groundwork for the more precise subtyping rules discussed in #32330, but does not enable them;
- it issues warnings when the result of a leak-check or subtyping check relies on a late-bound region which will late become early-bound when #32330 is fixed;
- it introduces a cache for projection in the inference context.
I'm not 100% happy with the approach taken by the cache here, but it seems like a step in the right direction. It results in big wins on some test cases, but not as big as previous versions -- I think because it is caching the `Vec<Obligation>` (whereas before I just returned the normalized type with an empty vector). However, that change was needed to fix an ICE in @alexcrichton's future-rs module (I haven't fully tracked the cause of that ICE yet). Also, because trans/the collector use a fresh inference context for every call to `fulfill_obligation`, they don't profit nearly as much from this cache as they ought to.
Still, here are the results from the future-rs `retry.rs`:
```
06:26 <nmatsakis> time: 6.246; rss: 44MB item-bodies checking
06:26 <nmatsakis> time: 54.783; rss: 63MB translation item collection
06:26 <nmatsakis> time: 140.086; rss: 86MB translation
06:26 <nmatsakis> time: 0.361; rss: 46MB item-bodies checking
06:26 <nmatsakis> time: 5.299; rss: 63MB translation item collection
06:26 <nmatsakis> time: 12.140; rss: 86MB translation
```
~~Another example is the example from #31849. For that, I get 34s to run item-bodies without any cache. The version of the cache included here takes 2s to run item-bodies type-checking. An alternative version which doesn't track nested obligations takes 0.2s, but that version ICEs on @alexcrichton's future-rs (and may well be incorrect, I've not fully convinced myself of that). So, a definite win, but I think there's definitely room for further progress.~~
Pushed a modified version which improves performance of the case from #31849:
```
lunch-box. time rustc --stage0 ~/tmp/issue-31849.rs -Z no-trans
real 0m33.539s
user 0m32.932s
sys 0m0.570s
lunch-box. time rustc --stage2 ~/tmp/issue-31849.rs -Z no-trans
real 0m0.195s
user 0m0.154s
sys 0m0.042s
```
Some sort of cache is also needed for unblocking further work on lazy normalization, since that will lean even more heavily on the cache, and will also require cycle detection.
r? @arielb1
Incr. comp. dep-node for traits, tests
Introduce new tests and also make dep-node for trait selection a bit more selective.
Fixes#33850
r? @michaelwoerister
MSVC requires unwinding code to be split to a tree of *funclets*, where each funclet
can only branch to itself or to to its parent.
Luckily, the code we generates matches this pattern. Recover that structure in
an analyze pass and translate according to that.
rustbuild: Clean more on `make clean`
Be sure to not use the old build cache for the bootstrap build system nor the
old caches of the compiler/cargo extractions (in case something went wrong).
Closes#33986
Support 16-bit pointers as well as i/usize
I'm opening this pull request to get some feedback from the community.
Although Rust doesn't support any platforms with a native 16-bit pointer at the moment, the [AVR-Rust][ar] fork is working towards that goal. Keeping this forked logic up-to-date with the changes in master has been onerous so I'd like to merge these changes so that they get carried along when refactoring happens. I do not believe this should increase the maintenance burden.
This is based on the original work of Dylan McKay (@dylanmckay).
[ar]: https://github.com/avr-rust/rust
Rename main thread from "<main>" to "main".
Fix issue #33789
We may need to discuss whether this counts as a breaking change since code may check the main thread name against "\<main\>". Discussion is in #33789
this introduces a DropAndReplace terminator as a fix to #30380. That terminator
is suppsoed to be translated by desugaring during drop elaboration, which is
not implemented in this commit, so this breaks `-Z orbit` temporarily.
Use Docker for Travis
The primary motivtion is to use system LLVM from ubuntu.com, instead of llvm.org.
Travis provides two environments: Ubuntu 12.04 LTS aka precise by default, and Ubuntu 14.04 LTS aka trusty if you specify dist: trusty. According to travis-ci/travis-ci#5821, Ubuntu 16.04 LTS aka xenial is unlikely to be available this year, and Travis recommends to use Docker.
LLVM 3.7 binary for 12.04 and 14.04 is not available from ubuntu.com, that's why we used llvm.org. But LLVM 3.7 binary for 16.04 is available from ubuntu.com, and we can use Docker to run on 16.04.
Fix#34009.
