This is a fairly large patch that implements all of the filesystem NB comments
and the relative paths changes (ex. adding weakly_canonical). These issues
and papers are all interrelated so their implementation couldn't be split up
nicely.
This patch upgrades <experimental/filesystem> to match the C++17 spec and not
the published experimental TS spec. Some of the changes in this patch are both
API and ABI breaking, however libc++ makes no guarantee about stability for
experimental implementations.
The major changes in this patch are:
* Implement NB comments for filesystem (P0492R2), including:
* Implement `perm_options` enum as part of NB comments, and update the
`permissions` function to match.
* Implement changes to `remove_filename` and `replace_filename`
* Implement changes to `path::stem()` and `path::extension()` which support
splitting examples like `.profile`.
* Change path iteration to return an empty path instead of '.' for trailing
separators.
* Change `operator/=` to handle absolute paths on the RHS.
* Change `absolute` to no longer accept a current path argument.
* Implement relative paths according to NB comments (P0219r1)
* Combine `path.cpp` and `operations.cpp` since some path functions require
access to the operations internals, and some fs operations require access
to the path parser.
llvm-svn: 329028
Summary:
This patch does the following:
1. Checks in a copy of the Google Benchmark library into the libc++ repo under `utils/google-benchmark`.
2. Teaches libc++ how to build Google Benchmark against both (A) in-tree libc++ and (B) the platforms native STL.
3. Allows performance benchmarks to be built as part of the libc++ build.
Building the benchmarks (and Google Benchmark) is off by default. It must be enabled using the CMake option `-DLIBCXX_INCLUDE_BENCHMARKS=ON`. When this option is enabled the tests under `libcxx/benchmarks` can be built using the `libcxx-benchmarks` target.
On Linux platforms where libstdc++ is the default STL the CMake option `-DLIBCXX_BUILD_BENCHMARKS_NATIVE_STDLIB=ON` can be used to build each benchmark test against libstdc++ as well. This is useful for comparing performance between standard libraries.
Support for benchmarks is currently very minimal. They must be manually run by the user and there is no mechanism for detecting performance regressions.
Known Issues:
* `-DLIBCXX_INCLUDE_BENCHMARKS=ON` is only supported for Clang, and not GCC, since the `-stdlib=libc++` option is needed to build Google Benchmark.
Reviewers: danalbert, dberlin, chandlerc, mclow.lists, jroelofs
Subscribers: chandlerc, dberlin, tberghammer, danalbert, srhines, hfinkel
Differential Revision: https://reviews.llvm.org/D22240
llvm-svn: 276049
Eric Fiselier