Follow-up to 6626f6fec3, this fixes the handling of -MT
* If no targets are provided, we need to invent one since cc1 expects
the driver to have handled it. The default is to use -o, quoting as
necessary for a make target.
* Fix the splitting for empty string, which was incorrectly treated as
{""} instead of {}.
* Add a way to test this behaviour in clang-scan-deps.
Differential Revision: https://reviews.llvm.org/D129607
When building modules, override secondary outputs (dependency file,
dependency targets, serialized diagnostic file) in addition to the pcm
file path. This avoids inheriting per-TU command-line options that
cause non-determinism in the results (non-deterministic command-line for
the module build, non-determinism in which TU's .diag and .d files will
contain the module outputs). In clang-scan-deps we infer whether to
generate dependency or serialized diagnostic files based on an original
command-line. In a real build system this should be modeled explicitly.
Differential Revision: https://reviews.llvm.org/D129389
Dependency scanning does not care about the order of submodules for
correctness, so sort the submodules so that we get the same
command-lines to build the module across different TUs. The order of
inferred submodules can vary depending on the order of #includes in the
including TU.
Differential Revision: https://reviews.llvm.org/D128008
Disable or canonicalize compiler options that are not relevant in
explicit module builds, similar to what we already did for the modules
cache path. This reduces uninteresting differences between
command-lines, which is particularly useful if there is a tool that can
cache the compilations.
Differential Revision: https://reviews.llvm.org/D127883
This fixes the underlying module dependencies, which had a
non-deterministic order, which was also visible in the order of calls to
DependencyConsumer methods. This was not directly observable in
the clang-scan-deps utility, because it was previously seeing a sorted
order from std::map in DependencyScanningTool. However, the underlying
API previously created a likely issue for any other clients. Note: if
you only apply the change from DependencyScanningTool, you can see the
issue in clang-scan-deps, and existing tests will fail
non-deterministicaly.
Differential Revision: https://reviews.llvm.org/D127243
This patch changes type of the `File` parameter in `PPCallbacks::InclusionDirective()` from `const FileEntry *` to `Optional<FileEntryRef>`.
With the API change in place, this patch then removes some uses of the deprecated `FileEntry::getName()` (e.g. in `DependencyGraph.cpp` and `ModuleDependencyCollector.cpp`).
Reviewed By: dexonsmith, bnbarham
Differential Revision: https://reviews.llvm.org/D123574
When pruning header search paths (to reduce the number of modules we need to build explicitly), we can't prune the search paths used in (transitive) dependencies of a module. Otherwise, we could end up with either of the following dependency graphs:
```
X:<hash1> -> Y:<hash2>
X:<hash1> -> Y:<hash3>
```
depending on the search paths of the translation unit we discovered `X` and `Y` from.
This patch fixes that.
Depends on D121295.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D121303
With explicit modules build, the '-fmodules-cache-path=' argument is unused.
This patch removes the argument to avoid warnings or errors (with '-Werror') stemming from that.
Depends on D118915.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D120474
The `clang-scan-deps` tool currently generates `-fmodule-file=` command-line arguments for the whole transitive closure of modular dependencies. This is not necessary, we only need to provide the direct dependencies on the command line. Information about transitive dependencies is stored within the `.pcm` files of direct dependencies. This makes the command lines shorter, but should be a NFC otherwise (unless there are bugs in the loading mechanism for explicit modules).
Depends on D120465.
Reviewed By: Bigcheese
Differential Revision: https://reviews.llvm.org/D118915
Since D113473, we don't report any module map files via `-fmodule-map-file=` in explicit builds. The ultimate goal here is to make sure Clang doesn't open/read/parse/evaluate unnecessary module maps.
However, implicit module maps still end up reading all reachable module maps. This patch disables implicit module maps in explicit builds.
Unfortunately, we still need to report some module map files that aren't encoded in PCM files of dependencies: module maps that are necessary to correctly evaluate includes in modules marked as `[no_undeclared_includes]`.
Depends on D120464.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D120465
This reverts commits:
- 04192422c4.
- 015e08c6ba
D114206 was landed before it was approved - and was landed knowing that
the test crashed on windows, without an xfail. The promised follow-up
commit with fixes has not appeared since it was promised on December 14th.
Make clang-scan-deps use the virtual path for module maps instead of the on disk
path. This is needed so that modulemap relative lookups are done correctly in
the actual module builds. The file dependencies still use the on disk path as
that's what matters for build invalidation.
Differential Revision: https://reviews.llvm.org/D114206
Some command-line codegen arguments are likely to differ between identical modules discovered from different translation units. This patch removes them to make builds deterministic and/or reduce the number of built modules.
Reviewed By: Bigcheese
Differential Revision: https://reviews.llvm.org/D112923
During explicit modules build, when all modules are provided via `-fmodule-file=<path>` and implicit modules and implicit module maps are disabled (`-fno-implicit-modules`, `-fno-implicit-module-maps`), we don't need to load the original module map files at all. This patch stops emitting the `-fmodule-map-file=` arguments we don't need, saving some compilation time due to avoiding parsing such module maps and making the command line shorter.
Reviewed By: bnbarham
Differential Revision: https://reviews.llvm.org/D113473
The dependency scanner works with multiple instances of `Compiler{Instance,Invocation}`. From names of the variables/members, their purpose is not obvious.
This patch gives descriptive name to the generated `CompilerInvocation` that can be used to derive the command-line to build a modular dependency.
Depends on D111725.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D111728
The dependency scanner works with multiple instances of `Compiler{Instance,Invocation}`. From names of the variables/members, their purpose is not obvious.
This patch gives a distinct name to the `CompilerInstance` that's used to run the implicit build during dependency scan.
Depends on D111724.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D111725
The `ModuleDepCollectorPP` class holds a reference to `ModuleDepCollector` as well as `ModuleDepCollector`'s `CompilerInstance`. The fact that these refer to the same object is non-obvious.
This patch removes the `CompilerInvocation` reference from `ModuleDepCollectorPP` and accesses it through `ModuleDepCollector` instead.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D111724
One of main goals of the dependency scanner is to be strict about module compatibility. This is achieved through strict context hash. This patch ensures that strict context hash is enabled not only during the scan itself (and its minimized implicit build), but also when actually reporting the dependency.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D111720
To reduce the number of explicit builds of a single module, we can try to squash multiple occurrences of the module with different command-lines (and context hashes) by removing benign command-line options. The greatest contributors to benign differences between command-lines are the header search paths.
In this patch, the lookup cache in `HeaderSearch` is used to identify paths that were actually used when implicitly building the module during scanning. This information is serialized into the unhashed control block of the implicitly-built PCM. The dependency scanner then loads this and may use it to prune the header search paths before computing the context hash of the module and generating the command-line.
We could also prune the header search paths when serializing `HeaderSearchOptions` into the PCM. That way, we could do it only once instead of every load of the PCM file by dependency scanner. However, that would result in a PCM file whose contents don't produce the same context hash as the original build, which is probably highly surprising.
There is an alternative approach to storing extra information into the PCM: wire up preprocessor callbacks to capture the used header search paths on-the-fly during preprocessing of modularized headers (similar to what we currently do for the main source file and textual headers). Right now, that's not compatible with the fact that we do an actual implicit build producing PCM files during dependency scanning. The second run of dependency scanner loads the PCM from the first run, skipping the preprocessing altogether, which would result in different results between runs. We can revisit this approach when we stop building implicitly during dependency scanning.
Depends on D102923.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D102488
There are a number of language and preprocessor options that are reset in the `CompilerInvocation` that describes the build of an implicit module. This patch uses the logic for explicit modules as well.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D108710
The `ASTReader` populates `Module::PresumedModuleMapFile` only for top-level modules, not submodules. To avoid generating empty `-fmodule-map-file=` arguments, make discovered modules depend on top-level precompiled modules. The granularity of submodules is not important here.
The documentation of `Module::PresumedModuleMapFile` says this field is non-empty only when building from preprocessed source. This means there can still be cases where the dependency scanner generates empty `-fmodule-map-file=` arguments. That's being addressed in separate patch: D108544.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D108647
In this patch, the dependency scanner starts collecting precompiled dependencies from all encountered submodules, not only from top-level modules.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D108540
Some files still contained the old University of Illinois Open Source
Licence header. This patch replaces that with the Apache 2 with LLVM
Exception licence.
Differential Revision: https://reviews.llvm.org/D107528
Whenever -fmodule-name=top_level_module name is parsed, and clang actually tries to
import top_level_module, the headers are imported textually and the module isn't actually
built. However, the dependency scanner could still record it as a potential dependency
if the module was reimported and thus recorded by the preprocessor callbacks.
This change avoids collecting this kind of module as a dependency by verifying that we don't
collect top level modules without actual PCM files.
Differential Revision: https://reviews.llvm.org/D106100
There's no need to pass `DependencyOutputOptions` to each call of `handleFileDependency`, since the options don't ever change.
This patch adds new `handleDependencyOutputOpts` method to the `DependencyConsumer` interface and the dependency scanner uses it to report the options only once.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D104104
One of the goals of the dependency scanner is to generate command-lines that can be used to explicitly build modular dependencies of a translation unit. The only modifications to these command-lines should be for the purposes of explicit modular build.
However, the current version of dependency scanner leaks its implementation details into the command-lines.
The first problem is that the `clang-scan-deps` tool adjusts the original textual command-line (adding `-Eonly -M -MT <target> -sys-header-deps -Wno-error -o /dev/null `, removing `--serialize-diagnostics`) in order to set up the `DependencyScanning` library. This has been addressed in D103461, D104012, D104030, D104031, D104033. With these patches, the `DependencyScanning` library receives the unmodified `CompilerInvocation`, sets it up and uses it for the implicit modular build.
Finally, to prevent leaking the implementation details to the resulting command-lines, this patch generates them from the **original** unmodified `CompilerInvocation` rather than from the one that drives the implicit build.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D104036
When a translation unit uses a PCH and imports the same modules as the PCH, we'd prefer to resolve to those modules instead of inventing new modules and reporting them as modular dependencies. Since the PCH modules have already been built nudge the compiler to reuse them when deciding whether to build a new module and don't report them as regular modular dependencies.
Depends on D103524 & D103802.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D103526
The `PreprocessOnlyAction` doesn't support loading the AST file of a precompiled header. This is problematic for dependency scanning, since the `#include` manufactured for the PCH is treated as textual. This means the PCH contents get scanned with each TU, which is redundant. Moreover, dependencies of the PCH end up being considered dependency of the TU.
To handle AST file of PCH properly, this patch creates new `FrontendAction` that behaves the same way `PreprocessorOnlyAction` does, but treats the manufactured PCH `#include` as a normal compilation would (by not claiming it only uses a preprocessor and creating the default AST consumer).
The AST file is now reported as a file dependency of the TU.
Depends on D103519.
Reviewed By: Bigcheese
Differential Revision: https://reviews.llvm.org/D103524
This reapplies commit 95033eb3 that reverted commit 1d9e8e13.
The tests were failing on Windows due to spaces and backslashes in paths not being handled carefully.
This patch adds support for inferred modules to the dependency scanner.
Effectively a cherry-pick of https://github.com/apple/llvm-project/pull/699 authored by @Bigcheese with libclang and other changes omitted.
Contains following changes:
1. [Clang][ScanDeps] Ignore __inferred_module.map dependency.
* This shows up with inferred modules, but it doesn't exist on disk, so don't report it as a dependency.
2. [Clang][ScanDeps] Use the module map a module was inferred from for inferred modules.
Also includes a smoke test that uses clang-scan-deps output to perform an explicit build. There's no intention to duplicate whatever `test/Modules` contains, just to verify the produced command-line does "work" (with very loose definition of work).
Split from D100934.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D102495
This patch eagerly constructs and modifies CompilerInvocation of modular dependencies in order to report the correct context hash instead of the hash of the original translation unit.
No functionality change here, since we currently don't modify CompilerInvocation in a way that affects the context hash.
Depends on D102473.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D102482
The context hash of modular dependencies can be different from the context hash of the original translation unit if we modify their `CompilerInvocation`s.
Stop assuming the TU's context hash everywhere.
No functionality change here, since we're still currently using the unmodified TU CompilerInvocation to compute the context hash.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D102473
Add option to `clang-scan-deps` to enable/disable generation of command-line arguments with absolute paths. This is essentially a revert of D100533, but with improved naming and added test.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D101051
This patch uses the new `CompilerInvocation::generateCC1CommandLine` to generate the full canonical command line for modular dependencies, instead of only appending additional arguments.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D100534
This patch removes the `-full-command-line` option from `clang-scan-deps`. It's only used with `-format=experimental-full`, where omitting the command lines doesn't make much sense. There are no tests without `-full-command-line`.
Depends on D100531.
Reviewed By: Bigcheese
Differential Revision: https://reviews.llvm.org/D100533
This patch simplifies (and renames) the `appendCommonModuleArguments` function.
It no longer tries to construct the command line for explicitly building modules. Instead, it only performs the DFS traversal of modular dependencies and queries the callbacks to collect paths to `.pcm` and `.modulemap` files.
This makes it more flexible and usable in two contexts:
* Generating additional command line arguments for the main TU in modular build. The `std::vector<std::string>` output parameters can be used to manually generate appropriate command line flags.
* Generate full command line for a module. The output parameters can be the corresponding parts of `CompilerInvocation`. (In a follow-up patch.)
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D100531
This patch documents how `ModuleDepCollector{,PP}` work and what their members store. Also renames somewhat vague `MainDeps` to `FileDeps` and `Deps` to `ModularDeps`.
Depends on D98943.
Reviewed By: Bigcheese
Differential Revision: https://reviews.llvm.org/D98950
This patch extracts the `ModuleName` and `ContextHash` members of `ClangModuleDep`, `FullDependencies` and `ModuleDeps` into a single struct `ModuleID`. This makes it easier to understand how the full dependency graph works.
Reviewed By: Bigcheese, dexonsmith
Differential Revision: https://reviews.llvm.org/D98943
`SourceManager::getFileEntryRefForID`'s remaining callers just want the
filename component, which is coming from the `FileInfo`. Replace the API
with `getNonBuiltinFilenameForID`, which also removes another use of
`FileEntryRef::FileEntryRef` outside of `FileManager`.
Both callers are collecting file dependencies, and one of them relied on
this API to filter out built-ins (as exposed by
clang/test/ClangScanDeps/modules-full.cpp). It seems nice to continue
providing that service.
Differential Revision: https://reviews.llvm.org/D89508
This is how it should've been and brings it more in line with
std::string_view. There should be no functional change here.
This is mostly mechanical from a custom clang-tidy check, with a lot of
manual fixups. It uncovers a lot of minor inefficiencies.
This doesn't actually modify StringRef yet, I'll do that in a follow-up.
Differential Revision: https://reviews.llvm.org/D70268
This is a recommit of f978ea4983 with a fix for the PowerPC failure.
The issue was that:
* `CompilerInstance::ExecuteAction` calls
`getTarget().adjust(getLangOpts());`.
* `PPCTargetInfo::adjust` changes `LangOptions::HasAltivec`.
* This happens after the first few calls to `getModuleHash`.
There’s even a FIXME saying:
```
// FIXME: We shouldn't need to do this, the target should be immutable once
// created. This complexity should be lifted elsewhere.
```
This only showed up on PowerPC because it's one of the few targets that
almost always changes a hashed langopt.
I looked into addressing the fixme, but that would be a much larger
change, and it's not the only thing that happens in `ExecuteAction` that
can change the module context hash. Instead I changed the code to not
call `getModuleHash` until after it has been modified in `ExecuteAction`.
Fix the confusing naming of `CompilerInstance::ModuleManager`. This is
actually an instance of `ASTReader`, which contains an instance of
`ModuleManager`. I have to assume there was a point in the past where
they were just one class, but it's been pretty confusing for a while. I
think it's time to fix it.
The new name is `TheASTReader`; the annoying `The` prefix is so that we
don't shadow the `ASTReader` class. I tried out `ASTRdr` but that
seemed less clear, and this choice matches `ThePCHContainerOperations`
just a couple of declarations below.
Also rename `CompilerInstance::getModuleManager` and
`CompilerInstance::createModuleManager` to `*ASTReader`, making some
cases of `getModuleManager().getModuleManager()` a little more clear.
https://reviews.llvm.org/D70583
This is a recommit of d8a4ef0e68 with the nondeterminism fixed.
This adds experimental support for extracting a Clang module dependency graph
from a compilation database. The output format is experimental and will change.
It is currently a concatenation of JSON outputs for each compilation. Future
patches will change this to deduplicate modules between compilations.
Differential Revision: https://reviews.llvm.org/D69420
Ben Langmuir