Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Rollup of 8 pull requests #71933

Closed
wants to merge 24 commits into from

Conversation

Dylan-DPC-zz
Copy link

Successful merges:

Failed merges:

r? @ghost

ssomers and others added 24 commits April 25, 2020 00:05
- the new interface allows to define the stack size
This also abstracts checking for a command into `require`.

Before:

```
Updating only changed submodules
Submodules updated in 0.01 seconds
Traceback (most recent call last):
  File "./x.py", line 11, in <module>
    bootstrap.main()
  ...
  File "/home/joshua/src/rust/src/bootstrap/bootstrap.py", line 137, in run
    ret = subprocess.Popen(args, **kwargs)
  File "/usr/lib/python2.7/subprocess.py", line 394, in __init__
    errread, errwrite)
  File "/usr/lib/python2.7/subprocess.py", line 1047, in _execute_child
    raise child_exception
OSError: [Errno 2] No such file or directory
```

After:

```
error: unable to run `curl --version`: [Errno 2] No such file or directory
Please make sure it's installed and in the path.
```
- Round to zero, and representable values cast directly.
- `NaN` goes to 0
- Values beyond the limits of the type are saturated to the "nearest value"
  (essentially rounding to zero, in some sense) in the integral type, so e.g.
  `f32::INFINITY` would go to `{u,i}N::MAX.`
…nikic

Define UB in float-to-int casts to saturate

This closes rust-lang#10184 by defining the behavior there to saturate infinities and values exceeding the integral range (on the lower or upper end). `NaN` is sent to zero.
…r=Mark-Simulacrum

Btreemap iter intertwined

3 commits:

1. Introduced benchmarks for `BTreeMap::iter()`. Benchmarks named `iter_20` were of the whole iteration process, so I renamed them. Also the benchmarks of `range` that I wrote earlier weren't very good. I included an (awkwardly named) one that compares `iter()` to `range(..)` on the same set, because the contrast is surprising:
```
 name                                           ns/iter
 btree::map::range_unbounded_unbounded          28,176
 btree::map::range_unbounded_vs_iter            89,369
```
Both dig up the same pair of leaf edges. `range(..)` also checks that some keys are correctly ordered, the only thing `iter()` does more is to copy the map's length.

2. Slightly refactoring the code to what I find more readable (not in chronological order of discovery), boosts performance:
```
>cargo-benchcmp.exe benchcmp a1 a2 --threshold 5
 name                                   a1 ns/iter  a2 ns/iter  diff ns/iter   diff %  speedup
 btree::map::find_rand_100              18          17                    -1   -5.56%   x 1.06
 btree::map::first_and_last_10k         64          71                     7   10.94%   x 0.90
 btree::map::iter_0                     2,939       2,209               -730  -24.84%   x 1.33
 btree::map::iter_1                     6,845       2,696             -4,149  -60.61%   x 2.54
 btree::map::iter_100                   8,556       3,672             -4,884  -57.08%   x 2.33
 btree::map::iter_10k                   9,292       5,884             -3,408  -36.68%   x 1.58
 btree::map::iter_1m                    10,268      6,510             -3,758  -36.60%   x 1.58
 btree::map::iteration_mut_100000       478,575     453,050          -25,525   -5.33%   x 1.06
 btree::map::range_unbounded_unbounded  28,176      36,169             7,993   28.37%   x 0.78
 btree::map::range_unbounded_vs_iter    89,369      38,290           -51,079  -57.16%   x 2.33
 btree::set::clone_100_and_remove_all   4,801       4,245               -556  -11.58%   x 1.13
 btree::set::clone_10k_and_remove_all   529,450     496,030          -33,420   -6.31%   x 1.07
```
But you can tell from the `range_unbounded_*` lines that, despite an unwarranted, vengeful attack on the range_unbounded_unbounded benchmark, this change still doesn't allow `iter()` to catch up with `range(..)`.

3. I guess that `range(..)` copes so well because it intertwines the leftmost and rightmost descend towards leaf edges, doing the two root node accesses close together, perhaps exploiting a CPU's internal pipelining? So the third commit distils a version of `range_search` (which we can't use directly because of the `Ord` bound), and we get another boost:
```
cargo-benchcmp.exe benchcmp a2 a3 --threshold 5
 name                                   a2 ns/iter  a3 ns/iter  diff ns/iter   diff %  speedup
 btree::map::first_and_last_100         40          43                     3    7.50%   x 0.93
 btree::map::first_and_last_10k         71          64                    -7   -9.86%   x 1.11
 btree::map::iter_0                     2,209       1,719               -490  -22.18%   x 1.29
 btree::map::iter_1                     2,696       2,205               -491  -18.21%   x 1.22
 btree::map::iter_100                   3,672       2,943               -729  -19.85%   x 1.25
 btree::map::iter_10k                   5,884       3,929             -1,955  -33.23%   x 1.50
 btree::map::iter_1m                    6,510       5,532               -978  -15.02%   x 1.18
 btree::map::iteration_mut_100000       453,050     476,667           23,617    5.21%   x 0.95
 btree::map::range_included_excluded    405,075     371,297          -33,778   -8.34%   x 1.09
 btree::map::range_included_included    427,577     397,440          -30,137   -7.05%   x 1.08
 btree::map::range_unbounded_unbounded  36,169      28,175            -7,994  -22.10%   x 1.28
 btree::map::range_unbounded_vs_iter    38,290      30,838            -7,452  -19.46%   x 1.24
```
But I think this is just fake news from the microbenchmarking media. `iter()` is still trying to catch up with `range(..)`. And we can sure do without another function. So I would skip this 3rd commit.

r? @Mark-Simulacrum
…ruppe

use new interface to create threads on HermitCore

- the new interface allows to define the stack size
- increase the default stack size to 1 MByte
…lacrum

SipHasher with keys initialized to 0 should just use new()

I believe that is what the `new()` is for, for good reasons.
…lacrum

x.py: Give a more helpful error message if curl isn't installed

Before:

```
Updating only changed submodules
Submodules updated in 0.01 seconds
Traceback (most recent call last):
  File "./x.py", line 11, in <module>
    bootstrap.main()
  ...
  File "/home/joshua/src/rust/src/bootstrap/bootstrap.py", line 137, in run
    ret = subprocess.Popen(args, **kwargs)
  File "/usr/lib/python2.7/subprocess.py", line 394, in __init__
    errread, errwrite)
  File "/usr/lib/python2.7/subprocess.py", line 1047, in _execute_child
    raise child_exception
OSError: [Errno 2] No such file or directory
```

After:

```
Updating only changed submodules
Submodules updated in 0.01 seconds

spurious failure, trying again

spurious failure, trying again

spurious failure, trying again

spurious failure, trying again
failed to run: curl -s -y 30 -Y 10 --connect-timeout 30 --retry 3 -Sf -o /tmp/tmpSWF21P.sha256 https://static.rust-lang.org/dist/2020-04-22/rust-std-beta-x86_64-unknown-linux-gnu.tar.gz.sha256: [Errno 2] No such file or directory
Build completed unsuccessfully in 0:00:00
```
Explain our RwLock implementation

Turns out that [with the latest POSIX docs](https://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_rwlock_wrlock.html), our `RwLock` implementation is actually correct. However, we cannot fully rely on that due to bugs in older glibc (fix released in 2016). Update the comments to explain that.

I also clarified our Mutex docs a bit and fixed another instance of rust-lang#55865.

r? @Amanieu
Fixes rust-lang#53127
…crum

Add command aliases from Cargo to x.py commands

Fixes rust-lang#71357
…k-Simulacrum

Backport 1.43.1 release notes to master

r? @Mark-Simulacrum
@Dylan-DPC-zz
Copy link
Author

@bors r+ rollup=never p=8

@bors
Copy link
Contributor

bors commented May 5, 2020

📌 Commit 382faf9 has been approved by Dylan-DPC

@bors bors added the S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. label May 5, 2020
@bors
Copy link
Contributor

bors commented May 5, 2020

⌛ Testing commit 382faf9 with merge 2c169b21198718172ecf3cfb8682f98f737fbb6b...

@bors
Copy link
Contributor

bors commented May 5, 2020

💔 Test failed - checks-actions

@bors bors added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. and removed S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. labels May 5, 2020
@Dylan-DPC-zz Dylan-DPC-zz deleted the rollup-09v4fa9 branch May 5, 2020 23:57
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
S-waiting-on-review Status: Awaiting review from the assignee but also interested parties.
Projects
None yet
Development

Successfully merging this pull request may close these issues.