NodeIds are sequential integers starting at zero, so we can achieve some
memory savings by just storing the items all in a line in a vector.
The occupancy for typical crates seems to be 75-80%, so we're already
more efficient than a HashMap (maximum occupancy 75%), not even counting
the extra book-keeping that HashMap does.
Previously an ExprLit was created *per byte* causing a huge increase in memory
bloat. This adds a new `lit_binary` to contain a literal of binary data, which
is currently only used by the include_bin! syntax extension. This massively
speeds up compilation times of the shootout-k-nucleotide-pipes test
before:
time: 469s
memory: 6GB
assertion failure in LLVM (section too large)
after:
time: 2.50s
memory: 124MB
Closes#2598
For the benefit of the pretty printer we want to keep track of how
string literals in the ast were originally represented in the source
code.
This commit changes parser functions so they don't extract strings from
the token stream without at least also returning what style of string
literal it was. This is stored in the resulting ast node for string
literals, obviously, for the package id in `extern mod = r"package id"`
view items, for the inline asm in `asm!()` invocations.
For `asm!()`'s other arguments or for `extern "Rust" fn()` items, I just
the style of string, because it seemed disproportionally cumbersome to
thread that information through the string processing that happens with
those string literals, given the limited advantage raw string literals
would provide in these positions.
The other syntax extensions don't seem to store passed string literals
in the ast, so they also discard the style of strings they parse.
According to http://huonw.github.io/isrustfastyet/mem/#012f909, the "const
marking" pass generates about 400MB of extra memory during compilation. It
appears that this is due to two different factors:
1. There is a `ccache` map in the ty::ctxt which is only ever used in this
pass, so this commit moves the map out of the ty::ctxt struct and into
just this pass's visitor. This turned out to not benefit that much in
memory (as indicated by http://i.imgur.com/Eo4iOzK.png), but it's helpful
to do nonetheless.
2. During const_eval, there are a lot of lookups into decoding inlined items
from external crates. There is no caching involved here, so the same
static or variant could be re-translated many times. After adding
separate caches for variants and statics, the memory peak of compiling
rustc decreased by 200MB (as evident by http://i.imgur.com/ULAUMtq.png)
The culmination of this is basically a slight reorganization of a caching map
for the const_eval pass along with a 200MB decrease in peak memory usage when
compiling librustc.
It is simply defined as `f64` across every platform right now.
A use case hasn't been presented for a `float` type defined as the
highest precision floating point type implemented in hardware on the
platform. Performance-wise, using the smallest precision correct for the
use case greatly saves on cache space and allows for fitting more
numbers into SSE/AVX registers.
If there was a use case, this could be implemented as simply a type
alias or a struct thanks to `#[cfg(...)]`.
Closes#6592
The mailing list thread, for reference:
https://mail.mozilla.org/pipermail/rust-dev/2013-July/004632.html
Like issue #9209, remove float::{from_str, from_str_radix} in favor of
the two corresponding traits. The same for modules f64 and f32.
New usage is
from_str::<float>("1.2e34")
- Made naming schemes consistent between Option, Result and Either
- Changed Options Add implementation to work like the maybe monad (return None if any of the inputs is None)
- Removed duplicate Option::get and renamed all related functions to use the term `unwrap` instead
This is preparation for removing `@fn`.
This does *not* use default methods yet, because I don't know
whether they work. If they do, a forthcoming PR will use them.
This also changes the precedence of `as`.
`crate => Crate`
`local => Local`
`blk => Block`
`crate_num => CrateNum`
`crate_cfg => CrateConfig`
Also, Crate and Local are not wrapped in spanned<T> anymore.
for cases where it's hard to decide what id to use for the lookup); modify
irrefutable bindings code to move or copy depending on the type, rather than
threading through a flag. Also updates how local variables and arguments are
registered. These changes were hard to isolate.
Mostly just low-haning fruit, i.e. function arguments that were @ even
though & would work just as well.
Reduces librustc.so size by 200k when compiling without -O, by 100k when
compiling with -O.
