clang-scan-deps contains some command line parsing and modifications.
This patch adds support for clang-cl command options.
Differential Revision: https://reviews.llvm.org/D92191
Previously, given a CompilationDatabase with two commands for the same
source file we would report that file twice with the union of the
dependencies for each command both times.
This was due to the way `ClangTool` runs actions given an input source
file (see the comment in `DependencyScanningTool.cpp`). This commit adds
a `SingleCommandCompilationDatabase` that is created with each
`CompileCommand` in the original CDB, which is then used for each
`ClangTool` invocation. This gives us a single run of
`DependencyScanningAction` per `CompileCommand`.
I looked at using `AllTUsToolExecutor` which is a parallel tool
executor, but I'm not sure it's suitable for `clang-scan-deps` as it
does a lot more sharing of state than `AllTUsToolExecutor` expects.
Differential Revision: https://reviews.llvm.org/D69643
This commit adds an optimization to clang-scan-deps and clang's preprocessor that skips excluded preprocessor
blocks by bumping the lexer pointer, and not lexing the tokens until reaching appropriate #else/#endif directive.
The skip positions and lexer offsets are computed when the file is minimized, directly from the minimized tokens.
On an 18-core iMacPro with macOS Catalina Beta I got 10-15% speed-up from this optimization when running clang-scan-deps on
the compilation database for a recent LLVM and Clang (3511 files).
Differential Revision: https://reviews.llvm.org/D67127
llvm-svn: 371656
This commit implements the fast dependency scanning mode in clang-scan-deps: the
preprocessing is done on files that are minimized using the dependency directives source minimizer.
A shared file system cache is used to ensure that the file system requests and source minimization
is performed only once. The cache assumes that the underlying filesystem won't change during the course
of the scan (or if it will, it will not affect the output), and it can't be evicted. This means that the
service and workers can be used for a single run of a dependency scanner, and can't be reused across multiple,
incremental runs. This is something that we'll most likely support in the future though.
Note that the driver still utilizes the underlying real filesystem.
This commit is also still missing the fast skipped PP block skipping optimization that I mentioned at EuroLLVM talk.
Additionally, the file manager is still not reused by the threads as well.
Differential Revision: https://reviews.llvm.org/D63907
llvm-svn: 368086
dependencies over a JSON compilation database
This commit introduces an outline for the clang-scan-deps tool that will be
used to implement fast dependency discovery phase using implicit modules for
explicit module builds.
The initial version of the tool works by computing non-modular header dependencies
for files in the compilation database without any optimizations
(i.e. without source minimization from r362459).
The tool spawns a number of worker threads to run the clang compiler workers in parallel.
The immediate goal for clang-scan-deps is to create a ClangScanDeps library
which will be used to build up this tool to use the source minimization and
caching multi-threaded filesystem to implement the optimized non-incremental
dependency scanning phase for a non-modular build. This will allow us to do
benchmarks and comparisons for performance that the minimization and caching give us
Differential Revision: https://reviews.llvm.org/D60233
llvm-svn: 363204
Sylvain Audi