Reapply r278457 with test fixed to not abouse fs case sensitivity.
When the VFS uses a YAML file, the real file path for a
virtual file is described in the "external-contents" field. Example:
...
{
'type': 'file',
'name': 'a.h',
'external-contents': '/a/b/c/a.h'
}
Currently, when parsing umbrella directories, we use
vfs::recursive_directory_iterator to gather the header files to generate the
equivalent modules for. If the external contents for a header does not exist,
we currently are unable to build a module, since the VFS
vfs::recursive_directory_iterator will fail when it finds an entry without a
reliable real path.
Since the YAML file could be prepared ahead of time and shared among
different compiler invocations, an entry might not yet have a reliable
path in 'external-contents', breaking the iteration.
Give the VFS the capability to skip such entries whenever
'ignore-non-existent-contents' property is set in the YAML file.
rdar://problem/27531549
llvm-svn: 278543
When the VFS uses a YAML file, the real file path for a
virtual file is described in the "external-contents" field. Example:
...
{
'type': 'file',
'name': 'a.h',
'external-contents': '/a/b/c/a.h'
}
Currently, when parsing umbrella directories, we use
vfs::recursive_directory_iterator to gather the header files to generate the
equivalent modules for. If the external contents for a header does not exist,
we currently are unable to build a module, since the VFS
vfs::recursive_directory_iterator will fail when it finds an entry without a
reliable real path.
Since the YAML file could be prepared ahead of time and shared among
different compiler invocations, an entry might not yet have a reliable
path in 'external-contents', breaking the iteration.
Give the VFS the capability to skip such entries whenever
'ignore-non-existent-contents' property is set in the YAML file.
rdar://problem/27531549
llvm-svn: 278457
Add 'ignore-non-existent-contents' to tell the VFS whether an invalid path
obtained via 'external-contents' should cause iteration on the VFS to stop.
If 'true', the VFS should ignore the entry and continue with the next. Allows
YAML files to be shared across multiple compiler invocations regardless of
prior existent paths in 'external-contents'. This global value is overridable
on a per-file basis.
This adds the parsing and write test part, but use by VFS comes next.
Differential Revision: https://reviews.llvm.org/D23422
rdar://problem/27531549
llvm-svn: 278456
Differential Revision: http://reviews.llvm.org/D19843
Corresponding LLVM change: http://reviews.llvm.org/D19842
Re-commit after addressing issues with of generating too many warnings for Windows and asan test failures.
Patch by Eric Niebler
llvm-svn: 272562
Reapply r269100 and r269270, reverted due to
https://llvm.org/bugs/show_bug.cgi?id=27725. Isolate the testcase that
corresponds to the new feature side of this commit and skip it on
windows hosts until we find why it does not work on these platforms.
Original commit message:
The way we currently build the internal VFS overlay representation leads
to inefficient path search and might yield wrong answers when asked for
recursive or regular directory iteration.
Currently, when reading an YAML file, each YAML root entry is placed
inside a new root in the filesystem overlay. In the crash reproducer, a
simple "@import Foundation" currently maps to 43 roots, and when looking
up paths, we traverse a directory tree for each of these different
roots, until we find a match (or don't). This has two consequences:
- It's slow.
- Directory iteration gives incomplete results since it only return
results within one root - since contents of the same directory can be
declared inside different roots, the result isn't accurate.
This is in part fault of the way we currently write out the YAML file
when emitting the crash reproducer - we could generate only one root and
that would make it fast and correct again. However, we should not rely
on how the client writes the YAML, but provide a good internal
representation regardless.
Build a proper virtual directory tree out of the YAML representation,
allowing faster search and proper iteration. Besides the crash
reproducer, this potentially benefits other VFS clients.
llvm-svn: 269327
The way we currently build the internal VFS overlay representation leads
to inefficient path search and might yield wrong answers when asked for
recursive or regular directory iteration.
Currently, when reading an YAML file, each YAML root entry is placed
inside a new root in the filesystem overlay. In the crash reproducer, a
simple "@import Foundation" currently maps to 43 roots, and when looking
up paths, we traverse a directory tree for each of these different
roots, until we find a match (or don't). This has two consequences:
- It's slow.
- Directory iteration gives incomplete results since it only return
results within one root - since contents of the same directory can be
declared inside different roots, the result isn't accurate.
This is in part fault of the way we currently write out the YAML file
when emitting the crash reproducer - we could generate only one root and
that would make it fast and correct again. However, we should not rely
on how the client writes the YAML, but provide a good internal
representation regardless.
This patch builds a proper virtual directory tree out of the YAML
representation, allowing faster search and proper iteration. Besides the
crash reproducer, this potentially benefits other VFS clients.
llvm-svn: 269270
Bruno made a couple valiant attempts but the bot is still red.
This reverts r269100 (primary commit), r269108 (fix attempt), r269133
(fix attempt).
llvm-svn: 269160
The way we currently build the internal VFS overlay representation leads
to inefficient path search and might yield wrong answers when asked for
recursive or regular directory iteration.
Currently, when reading an YAML file, each YAML root entry is placed
inside a new root in the filesystem overlay. In the crash reproducer, a
simple "@import Foundation" currently maps to 43 roots, and when looking
up paths, we traverse a directory tree for each of these different
roots, until we find a match (or don't). This has two consequences:
- It's slow.
- Directory iteration gives incomplete results since it only return
results within one root - since contents of the same directory can be
declared inside different roots, the result isn't accurate.
This is in part fault of the way we currently write out the YAML file
when emitting the crash reproducer - we could generate only one root and
that would make it fast and correct again. However, we should not rely
on how the client writes the YAML, but provide a good internal
representation regardless.
This patch builds a proper virtual directory tree out of the YAML
representation, allowing faster search and proper iteration. Besides the
crash reproducer, this potentially benefits other VFS clients.
llvm-svn: 269100
Hide the real paths when rebuilding from VFS by setting up the crash
reproducer to use 'use-external-names' = false. This way we avoid
module redifinition errors and consistently use the same paths against
all modules.
With this change on Darwin we are able to simulate a crash for a simple
application using "Foundation/Foundation.h" (which relies on a bunch of
different frameworks and headers) and successfully rebuild all the
modules by relying solely at the VFS overlay.
llvm-svn: 266234
The VFS YAML files contain empty directory entries to describe that it's
returning from a subdirectory before describing new files in the parent.
In the future, we should properly sort and write YAML files avoiding
such empty dirs and mitigate the extra recurson cost. However, since
this is used by previous existing YAMLs, make the traversal work in
their presence.
rdar://problem/24499339
llvm-svn: 264970
The FileSystem::makeAbsolute function has been calculating the current
working directory unconditionally, even when it is not needed. This calls
down to llvm::sys::fs::current_path, which is relatively expensive
because it stats two directories, regardless of whether those paths are
already in the stat cache. The net effect is that when using the
VFS, every stat during header search turns into three stats. With this
change, we get back to a single stat for absolute directory paths.
llvm-svn: 264519
This reapplies r261552 and r263748. Fixed testcase to reapply.
The VFS overlay mapping between virtual paths and real paths is done through
the 'external-contents' entries in YAML files, which contains hardcoded paths
to the real files.
When a module compilation crashes, headers are dumped into <name>.cache/vfs
directory and are mapped via the <name>.cache/vfs/vfs.yaml. The script
generated for reproduction uses -ivfsoverlay pointing to file to gather the
mapping between virtual paths and files inside <name>.cache/vfs. Currently, we
are only capable of reproducing such crashes in the same machine as they
happen, because of the hardcoded paths in 'external-contents'.
To be able to reproduce a crash in another machine, this patch introduces a new
option in the VFS yaml file called 'overlay-relative'. When it's equal to
'true' it means that the provided path to the YAML file through the
-ivfsoverlay option should also be used to prefix the final path for every
'external-contents'.
Example, given the invocation snippet "... -ivfsoverlay
<name>.cache/vfs/vfs.yaml" and the following entry in the yaml file:
"overlay-relative": "true",
"roots": [
...
"type": "directory",
"name": "/usr/include",
"contents": [
{
"type": "file",
"name": "stdio.h",
"external-contents": "/usr/include/stdio.h"
},
...
Here, a file manager request for virtual "/usr/include/stdio.h", that will map
into real path "/<absolute_path_to>/<name>.cache/vfs/usr/include/stdio.h.
This is a useful feature for debugging module crashes in machines other than
the one where the error happened.
Differential Revision: http://reviews.llvm.org/D17457
rdar://problem/24499339
llvm-svn: 263893
This reapplies r261552.
The VFS overlay mapping between virtual paths and real paths is done through
the 'external-contents' entries in YAML files, which contains hardcoded paths
to the real files.
When a module compilation crashes, headers are dumped into <name>.cache/vfs
directory and are mapped via the <name>.cache/vfs/vfs.yaml. The script
generated for reproduction uses -ivfsoverlay pointing to file to gather the
mapping between virtual paths and files inside <name>.cache/vfs. Currently, we
are only capable of reproducing such crashes in the same machine as they
happen, because of the hardcoded paths in 'external-contents'.
To be able to reproduce a crash in another machine, this patch introduces a new
option in the VFS yaml file called 'overlay-relative'. When it's equal to
'true' it means that the provided path to the YAML file through the
-ivfsoverlay option should also be used to prefix the final path for every
'external-contents'.
Example, given the invocation snippet "... -ivfsoverlay
<name>.cache/vfs/vfs.yaml" and the following entry in the yaml file:
"overlay-relative": "true",
"roots": [
...
"type": "directory",
"name": "/usr/include",
"contents": [
{
"type": "file",
"name": "stdio.h",
"external-contents": "/usr/include/stdio.h"
},
...
Here, a file manager request for virtual "/usr/include/stdio.h", that will map
into real path "/<absolute_path_to>/<name>.cache/vfs/usr/include/stdio.h.
This is a useful feature for debugging module crashes in machines other than
the one where the error happened.
Differential Revision: http://reviews.llvm.org/D17457
rdar://problem/24499339
llvm-svn: 263748
This was applied twice r261551 and 263617 and later reverted because:
(1) Windows bot failing on unittests. Change the current behavior to do
not handle path traversals on windows.
(2) Windows bot failed to include llvm/Config/config.h in order to use
HAVE_REALPATH. Use LLVM_ON_UNIX instead, as done in lib/Basic/FileManager.cpp.
Handle ".", ".." and "./" with trailing slashes while collecting files
to be dumped into the vfs overlay directory.
Include the support for symlinks into components. Given the path:
/install-dir/bin/../lib/clang/3.8.0/include/altivec.h, if "bin"
component is a symlink, it's not safe to use `path::remove_dots` here,
and `realpath` is used to get the right answer. Since `realpath`
is expensive, we only do it at collecting time (which only happens
during the crash reproducer) and cache the base directory for fast lookups.
Overall, this makes the input to the VFS YAML file to be canonicalized
to never contain traversal components.
Differential Revision: http://reviews.llvm.org/D17104
rdar://problem/24499339
llvm-svn: 263686
Bruno Cardoso Lopes
Taewook Oh
Benjamin Kramer
Sean Silva
Bob Wilson