This PR solves one of the pain points with c-style enums. Simplifies writing a fn to convert from an int/uint to an enum. It does this through a `#[deriving(FromPrimitive)]` syntax extension.
Before this is committed though, we need to discuss if `ToPrimitive`/`FromPrimitive` has the right design (cc #4819). I've changed all the `.to_int()` and `from_int()` style functions to return `Option<int>` so we can handle partial functions. For this PR though only enums and `extra::num::bigint::*` take advantage of returning None for unrepresentable values. In the long run it'd be better if `i64.to_i8()` returned `None` if the value was too large, but I'll save this for a future PR.
Closes#3868.
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.
Avoid cloning the stack on every `push_ctxt` call in trans
Rewrite the use of TLS variable for `push_ctxt` so that it uses a ~[]
instead of a @~[]. Before it cloned the whole vector on each push and
pop, which is unnecessary.
Rewrite the use of TLS variable for `push_ctxt` so that it uses a ~[]
instead of a @~[]. Before it cloned the whole vector on each push and
pop, which is unnecessary.
rustc: Use static strings in a few literals
Avoid allocating extra copies of strings by using "" instead of ~"" for
the debug options list and for the `time` function. This is a small
change, but it is in a path that's always executed.
Avoid allocating extra copies of strings by using "" instead of ~"" for
the debug options list and for the `time` function. This is a small
change, but it is in a path that's always executed.
This purges about 500 lines of visitor cruft from lint passes. All lints are
handled in a much more sane way at this point. The other huge bonus of this
commit is that there are no more @-boxes in the lint passes, fixing the 500MB
memory regression seen when the lint passes were refactored.
Closes#8589
This purges about 500 lines of visitor cruft from lint passes. All lints are
handled in a much more sane way at this point. The other huge bonus of this
commit is that there are no more @-boxes in the lint passes, fixing the 500MB
memory regression seen when the lint passes were refactored.
Closes#8589
This fixes two existing bugs along the way:
* The `transmute` intrinsic did not correctly handle casts of immediate
aggregates like newtype structs and tuples.
* The code for calling foreign functions used the wrong type to create
an `alloca` temporary
enum Foo { A, B }
fn foo() -> Foo { A }
Before:
; Function Attrs: nounwind uwtable
define void @_ZN3foo18hbedc642d5d9cf5aag4v0.0E(%enum.Foo* noalias nocapture sret, { i64, %tydesc*, i8*, i8*, i8 }* nocapture readnone) #0 {
"function top level":
%2 = getelementptr inbounds %enum.Foo* %0, i64 0, i32 0
store i64 0, i64* %2, align 8
ret void
}
After:
; Function Attrs: nounwind readnone uwtable
define %enum.Foo @_ZN3foo18hbedc642d5d9cf5aag4v0.0E({ i64, %tydesc*, i8*, i8*, i8 }* nocapture readnone) #0 {
"function top level":
ret %enum.Foo zeroinitializer
}
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
This change adds --soft-float option for generating
software floating point library calls.
It also implies using soft float ABI, that is the same as llc.
It is useful for targets that have no FPU.
This change adds -Z soft-float option for generating
software floating point library calls.
It also implies using soft float ABI, that is the same as llc.
It is useful for targets that have no FPU.
This is mostly an incremental change, picking off some uses of
@- or @mut-pointers that can be replaced by references.
Almost all of the builder functions in trans::build are updated,
mostly using `&Block` arguments instead of `@mut Block`.
Use &mut Block and &Block references where possible in the builder
functions in trans::build.
@mut Block remains in a few functions where I could not (not yet at
least) track down the runtime borrowck failures.
