This is in preparation for making discriminants not always be int (#1647), but it also makes compiles for a 64-bit target not behave differently — with respect to how many bits of discriminants are preserved — depending on the build host's word size, which is a nice property to have.
We may want to standardize how to abbreviate "discriminant" in a followup change.
This does two things: 1) stops compressing metadata, 2) stops copying the metadata section, instead holding a reference to the buffer returned by the LLVM section iterator.
Not compressing metadata requires something like 7x the storage space, but makes running tests about 9% faster. This has been a time improvement on all platforms I've tested, including windows. I considered leaving compression as an option but it doesn't seem to be worth the complexity since we don't currently have any use cases where we need to save that space.
In order to avoid copying the metadata section I had to hack up extra::ebml a bit to support unsafe buffers. We should probably move it into librustc so that it can evolve to support the compiler without worrying about having a crummy interface.
r? @graydon
Add new methods `.rsplit_iter()` and `.rsplitn_iter()` for &str.
Separate out CharSplitIterator and CharSplitNIterator,
CharSplitIterator (`split_iter` and `rsplit_iter`) is made double-ended
while `splitn_iter` and `rsplitn_iter` (limited to N splits) are not,
since these don't have the same symmetry.
With CharSplitIterator being double ended, derived iterators like
`line_iter` and `word_iter` are too.
Recent improvements to `&mut Trait` have made this work possible, and it solidifies that `ifmt` doesn't always have to return a string, but rather it's based around writers.
The method names in std::rt::io::extensions::WriterByteConversions are
the same as those in std::io::WriterUtils and a resolve error causes
rustc to fail after trying to find an impl of io::Writer instead of
trying to look for rt::io::Writer as well.
These new macros are all based on format! instead of fmt! and purely exist for
bootstrapping purposes. After the next snapshot, all uses of logging will be
migrated to these macros, and then after the next snapshot after that we can
drop the `2` suffix on everything
These aren't used for anything at the moment and cause some TLS hits
on some perf-critical code paths. Will need to put better thought into
it in the future.