introduce a specializes cache
This query is frequently used during trait selection and caching the
result can be a reasonable performance win.
The one case I examined thus far was the mrusty package (v0.5.1), where I saw an improvement in "typeck item bodies" from ~8.3s to ~1.9s.
r? @aturon
syntax_ext: format: nest_level's are no more
Just noticed this while working on #33642 and here's a quick fix, shouldn't touch anything else. It's some historic code indeed...
When displaying the function parameters for a lifetime elision error message,
this changes it to first filter out the parameters that don't have elided
lifetimes.
Fixes#30255.
Warnings for issue #32330
This is an extension of the previous PR that issues warnings in more situations than before. It does not handle *all* cases of #32330 but I believe it issues warnings for all cases I've seen in practice.
Before merging I'd like to address:
- open a good issue explaining the problem and how to fix it (I have a [draft writeup][])
- work on the error message, which I think is not as clear as it could/should be (suggestions welcome)
r? @aturon
[draft writeup]: https://gist.github.com/nikomatsakis/631ec8b4af9a18b5d062d9d9b7d3d967
Added a big-picture explanation for thread::park() & co.
As I said in https://www.reddit.com/r/rust/comments/4ihvv1/hey_rust_programmers_got_a_question_ask_here/d372s4i, the current explanation of the `park()` and `unpark()` is a bit unclear. It says that they're used for blocking, but then it goes on explaining the semantics in detail, leaving the bigger picture a bit unclear.
I added a short high-level explanation that explains how the functions are used. I also exposed the full paths (`thread::park()` and `thread::Thread::unpark()`), because `unpark()`, being a method, is not directly visible at the module level.
Update i686-linux-android features to match android x86 ABI.
Based on [android's official x86 ABI info](http://developer.android.com/ndk/guides/abis.html#x86), the x86 baseline CPU can be safely updated to `pentiumpro`, with the addition of `MMX`, `SSE`, `SSE2`, `SSE3`, `SSSE3` features.
r? @alexcrichton
Replace the obligation forest with a graph
In the presence of caching, arbitrary nodes in the obligation forest can be merged, which makes it a general graph. Handle it as such, using cycle-detection algorithms in the processing.
I should do performance measurements sometime.
This was pretty much written as a proof-of-concept. Please help me write this in a less-ugly way. I should also add comments explaining what is going on.
r? @nikomatsakis
The abs_sub name is misleading: the function actually computes the
positive difference (`fdim` in C), not the `(x - y).abs()` that *many* people expect
from the name.
This function can be replaced with just `(x - y).max(0.0)`, mirroring
the `abs` version, but this behaves differently with NAN: `NAN.max(0.0)
== 0.0`, while `NAN.positive_diff(0.0) == NAN`. People who absolutely
need that behaviour can use the C function directly and/or talk to the libs
team (we haven't encountered a concrete use-case for this functionality).
Closes#30315.
add UI testing framework
This adds a framework for capturing and tracking the precise output of rustc, which allows us to check all manner of minor details with the output. It's pretty strict right now -- the output must match almost exactly -- and hence maybe a bit too strict. But I figure we can add wildcards or whatever later. There is also a script intended to make updating the references easy, though the script could make things a *bit* easier (in particular, it'd be nice if it would find the build directory for you automatically).
One thing I was wondering about is the best way to test colors. Since windows doesn't embed those in the output stream, this test framework can't test colors on windows -- so I figure we can just write tests that are ignored on windows and which pass `--color=always` or whatever to rustc.
cc @jonathandturner
r? @alexcrichton
Update aarch64-linux-android target to match android abi.
- Changed `target_env` to "gnu" to empty "" for all android targets because it does not matter for android.
- The PR #33048 added "max_atomic_width" for arm-android but missed recently added armv7-android. Add it there too.
- Added features `+neon,+fp-armv8` because they [must exist on `aarch64` android](http://developer.android.com/ndk/guides/cpu-features.html).
- Update libc to include https://github.com/rust-lang/libc/pull/282 so that rust's std lib works on android's aarch64 (the main issue there was incorrect structure alignment on 64-bit arm).
r? @alexcrichton
Fix fast path of float parsing on x87
The fast path of the float parser relies on the rounding to happen
exactly and directly to the correct number of bits. On x87, instead,
double rounding would occour as the FPU stack defaults to 80 bits of
precision.
This can be fixed by setting the precision of the FPU stack before
performing the int to float conversion. This can be achieved by
changing the value of the x87 control word. This is a somewhat common
operation that is in fact performed whenever a float needs to be
truncated to an integer, but it is undesirable to add its overhead for
code that does not rely on x87 for computations (i.e. on non-x86
architectures, or x86 architectures which perform FPU computations on
using SSE).
Fixes `num::dec2flt::fast_path_correct` (on x87).
