Rollup of 9 pull requests #61758
Merged
Rollup of 9 pull requests #61758
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This should be used when trying to get at subsets of a larger span, especially when the larger span is not available in the code attempting to work with those subsets (especially common in the fmt_macros crate). This is usually a good replacement for (BytePos, BytePos) and (usize, usize) tuples. This commit also removes from_inner_byte_pos, since it took usize arguments, which is error prone.
We mistakenly pass cxxflags from the configuration to LLVM build as CMAKE_C_FLAGS.
...and are only included in a single variant.
This commit adds a script which we'll execute on Azure Pipelines which is intended to run in the background and passively collect CPU usage statistics for our builders. The intention here is that we can use this information over time to diagnose issues with builders, see where we can optimize our build, fix parallelism issues, etc. This might not end up being too useful in the long run but it's data we've wanted to collect for quite some time now, so here's a stab at it! Comments about how this is intended to work can be found in the python script used here to collect CPU usage statistics. Closes rust-lang#48828
also consistently mark all these is_* methods for inlining
…ddyb Generator optimization: Overlap locals that never have storage live at the same time The specific goal of this optimization is to optimize async fns which use `await!`. Notably, `await!` has an enclosing scope around the futures it awaits ([definition](https://github.com/rust-lang/rust/blob/08bfe16129b0621bc90184f8704523d4929695ef/src/libstd/macros.rs#L365-L381)), which we rely on to implement the optimization. More generally, the optimization allows overlapping the storage of some locals which are never storage-live at the same time. **We care about storage-liveness when computing the layout, because knowing a field is `StorageDead` is the only way to prove it will not be accessed, either directly or through a reference.** To determine whether we can overlap two locals in the generator layout, we look at whether they might *both* be `StorageLive` at any point in the MIR. We use the `MaybeStorageLive` dataflow analysis for this. We iterate over every location in the MIR, and build a bitset for each local of the locals it might potentially conflict with. Next, we assign every saved local to one or more variants. The variants correspond to suspension points, and we include the set of locals live across a given suspension point in the variant. (Note that we use liveness instead of storage-liveness here; this ensures that the local has actually been initialized in each variant it has been included in. If the local is not live across a suspension point, then it doesn't need to be included in that variant.). It's important to note that the variants are a "view" into our layout. For the layout computation, we use a simplified approach. 1. Start with the set of locals assigned to only one variant. The rest are disqualified. 2. For each pair of locals which may conflict *and are not assigned to the same variant*, we pick one local to disqualify from overlapping. Disqualified locals go into a non-overlapping "prefix" at the beginning of our layout. This means they always have space reserved for them. All the locals that are allowed to overlap in each variant are then laid out after this prefix, in the "overlap zone". So, if A and B were disqualified, and X, Y, and Z were all eligible for overlap, our generator might look something like this: You can think of a generator as an enum, where some fields are shared between variants. e.g. ```rust enum Generator { Unresumed, Poisoned, Returned, Suspend0(A, B, X), Suspend1(B), Suspend2(A, Y, Z), } ``` where every mention of `A` and `B` refer to the same field, which does not move when changing variants. Note that `A` and `B` would automatically be sent to the prefix in this example. Assuming that `X` is never `StorageLive` at the same time as either `Y` or `Z`, it would be allowed to overlap with them. Note that if two locals (`Y` and `Z` in this case) are assigned to the same variant in our generator, their memory would never overlap in the layout. Thus they can both be eligible for the overlapping section, even if they are storage-live at the same time. --- Depends on: - [x] rust-lang#59897 Multi-variant layouts for generators - [x] rust-lang#60840 Preserve local scopes in generator MIR - [x] rust-lang#61373 Emit StorageDead along unwind paths for generators Before merging: - [x] ~Wrap the types of all generator fields in `MaybeUninitialized` in layout::ty::field~ (opened rust-lang#60889) - [x] Make PR description more complete (e.g. explain why storage liveness is important and why we have to check every location) - [x] Clean up TODO - [x] Fix the layout code to enforce that the same field never moves around in the generator - [x] Add tests for async/await - [x] ~Reduce # bits we store by half, since the conflict relation is symmetric~ (note: decided not to do this, for simplicity) - [x] Store liveness information for each yield point in our `GeneratorLayout`, that way we can emit more useful debuginfo AND tell miri which fields are definitely initialized for a given variant (see discussion at rust-lang#59897 (comment))
…odrAus Implement Clone::clone_from for Option and Result See rust-lang#28481
…r=estebank Use Symbol, Span in libfmt_macros I'm not super happy with this, personally, but I think it might be a decent start -- happy to take suggestions as to how to expand this or change things further. r? @estebank Fixes rust-lang#60795
…=pietroalbini ci: Collect CPU usage statistics on Azure This commit adds a script which we'll execute on Azure Pipelines which is intended to run in the background and passively collect CPU usage statistics for our builders. The intention here is that we can use this information over time to diagnose issues with builders, see where we can optimize our build, fix parallelism issues, etc. This might not end up being too useful in the long run but it's data we've wanted to collect for quite some time now, so here's a stab at it! Comments about how this is intended to work can be found in the python script used here to collect CPU usage statistics. Closes rust-lang#48828
…n_rustc, r=oli-obk,Centril use pattern matching for slices destructuring refs rust-lang#61542 Use slices pattern where it seems to make sense .
implement nth_back for Range(Inclusive) This is part of rust-lang#54054.
is_fp and is_floating_point do the same thing, remove the former also consistently mark all these `is_*` methods for inlining
Pass cflags rather than cxxflags to LLVM as CMAKE_C_FLAGS We mistakenly pass cxxflags from the configuration to LLVM build as CMAKE_C_FLAGS.
Migrate rust-by-example to MdBook2
|
@bors r+ p=9 rollup=never |
|
📌 Commit 4748b5b has been approved by |
bors
added
the
S-waiting-on-bors
bors
added a commit
that referenced
this pull request
Jun 12, 2019
Rollup of 9 pull requests Successful merges: - #60187 (Generator optimization: Overlap locals that never have storage live at the same time) - #61348 (Implement Clone::clone_from for Option and Result) - #61568 (Use Symbol, Span in libfmt_macros) - #61632 (ci: Collect CPU usage statistics on Azure) - #61654 (use pattern matching for slices destructuring) - #61671 (implement nth_back for Range(Inclusive)) - #61688 (is_fp and is_floating_point do the same thing, remove the former) - #61705 (Pass cflags rather than cxxflags to LLVM as CMAKE_C_FLAGS) - #61734 (Migrate rust-by-example to MdBook2) Failed merges: r? @ghost
|
#60187 has been merged (conflict-prone might happen). |
|
☀️ Test successful - checks-travis, status-appveyor |
rust-highfive
added a commit
to rust-lang-nursery/rust-toolstate
that referenced
this pull request
Jun 12, 2019
Tested on commit rust-lang/rust@c4797fa. Direct link to PR: <rust-lang/rust#61758> 💔 rls on linux: test-pass → test-fail (cc @Xanewok, @rust-lang/infra).
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Successful merges:
Failed merges:
r? @ghost