I'd really like to be able to do something like
```rust
struct MapChain<'next, K, V> {
info: BlockInfo,
map: HashMap<K, V>,
next: Option<&'next mut MapChain<'next, K, V>
}
```
but I can't get the lifetimes to work out.
The resulting symbol names aren't very pretty at all:
trait Trait { fn method(&self); }
impl<'a> Trait for ~[(&'a int, fn())] { fn method(&self) {} }
gives
Trait$$UP$$VEC$$TUP_2$$BP$int$$FN$$::method::...hash...::v0.0
However, at least it contain some reference to the Self type, unlike
`Trait$__extensions__::method:...`, which is what the symbol name used
to be for anything other than `impl Trait for foo::bar::Baz` (which
became, and still becomes, `Trait$Baz::method`).
I'd really like to be able to do something like
struct MapChain<'next, K, V> {
info: BlockInfo,
map: HashMap<K, V>,
next: Option<&'next mut MapChain<'next, K, V>
}
but I can't get the lifetimes to work out.
Note that this removes a number of run-pass tests which are exercising behavior
of the old runtime. This functionality no longer exists and is thoroughly tested
inside of libgreen and libnative. There isn't really the notion of "starting the
runtime" any more. The major notion now is "bootstrapping the initial task".
This extracts everything related to green scheduling from libstd and introduces
a new libgreen crate. This mostly involves deleting most of std::rt and moving
it to libgreen.
Along with the movement of code, this commit rearchitects many functions in the
scheduler in order to adapt to the fact that Local::take now *only* works on a
Task, not a scheduler. This mostly just involved threading the current green
task through in a few locations, but there were one or two spots where things
got hairy.
There are a few repercussions of this commit:
* tube/rc have been removed (the runtime implementation of rc)
* There is no longer a "single threaded" spawning mode for tasks. This is now
encompassed by 1:1 scheduling + communication. Convenience methods have been
introduced that are specific to libgreen to assist in the spawning of pools of
schedulers.
This uses quite a bit of unsafe code for speed and failure safety, and allocates `2*n` temporary storage.
[Performance](https://gist.github.com/huonw/5547f2478380288a28c2):
| n | new | priority_queue | quick3 |
|-------:|---------:|---------------:|---------:|
| 5 | 200 | 155 | 106 |
| 100 | 6490 | 8750 | 5810 |
| 10000 | 1300000 | 1790000 | 1060000 |
| 100000 | 16700000 | 23600000 | 12700000 |
| sorted | 520000 | 1380000 | 53900000 |
| trend | 1310000 | 1690000 | 1100000 |
(The times are in nanoseconds, having subtracted the set-up time (i.e. the `just_generate` bench target).)
I imagine that there is still significant room for improvement, particularly because both priority_queue and quick3 are doing a static call via `Ord` or `TotalOrd` for the comparisons, while this is using a (boxed) closure.
Also, this code does not `clone`, unlike `quick_sort3`; and is stable, unlike both of the others.
Right now the --crate-id and related flags are all process *after* the entire
crate is parsed. This is less than desirable when used with makefiles because it
means that just to learn the output name of the crate you have to parse the
entire crate (unnecessary).
This commit changes the behavior to lift the handling of these flags much sooner
in the compilation process. This allows us to not have to parse the entire crate
and only have to worry about parsing the crate attributes themselves. The
related methods have all been updated to take an array of attributes rather than
a crate.
Additionally, this ceases duplication of the "what output are we producing"
logic in order to correctly handle things in the case of --test.
Finally, this adds tests for all of this functionality to ensure that it does
not regress.
