Introduce `MacroExpansionContext` to track what and how macros in a translation
unit expand. This is the first element of the patch-stack in this direction.
The main goal is to substitute the current macro expansion generator in the
`PlistsDiagnostics`, but all the other `DiagnosticsConsumer` could benefit from
this.
`getExpandedText` and `getOriginalText` are the primary functions of this class.
The former can provide you the text that was the result of the macro expansion
chain starting from a `SourceLocation`.
While the latter will tell you **what text** was in the original source code
replaced by the macro expansion chain from that location.
Here is an example:
void bar();
#define retArg(x) x
#define retArgUnclosed retArg(bar()
#define BB CC
#define applyInt BB(int)
#define CC(x) retArgUnclosed
void unbalancedMacros() {
applyInt );
//^~~~~~~~~~^ is the substituted range
// Original text is "applyInt )"
// Expanded text is "bar()"
}
#define expandArgUnclosedCommaExpr(x) (x, bar(), 1
#define f expandArgUnclosedCommaExpr
void unbalancedMacros2() {
int x = f(f(1)) )); // Look at the parenthesis!
// ^~~~~~^ is the substituted range
// Original text is "f(f(1))"
// Expanded text is "((1,bar(),1,bar(),1"
}
Might worth investigating how to provide a reusable component, which could be
used for example by a standalone tool eg. expanding all macros to their
definitions.
I borrowed the main idea from the `PrintPreprocessedOutput.cpp` Frontend
component, providing a `PPCallbacks` instance hooking the preprocessor events.
I'm using that for calculating the source range where tokens will be expanded
to. I'm also using the `Preprocessor`'s `OnToken` callback, via the
`Preprocessor::setTokenWatcher` to reconstruct the expanded text.
Unfortunately, I concatenate the token's string representation without any
whitespaces except if the token is an identifier when I emit an extra space
to produce valid code for `int var` token sequences.
This could be improved later if needed.
Patch-stack:
1) D93222 (this one) Introduces the MacroExpansionContext class and unittests
2) D93223 Create MacroExpansionContext member in AnalysisConsumer and pass
down to the diagnostics consumers
3) D93224 Use the MacroExpansionContext for macro expansions in plists
It replaces the 'old' macro expansion mechanism.
4) D94673 API for CTU macro expansions
You should be able to get a `MacroExpansionContext` for each imported TU.
Right now it will just return `llvm::None` as this is not implemented yet.
5) FIXME: Implement macro expansion tracking for imported TUs as well.
It would also relieve us from bugs like:
- [fixed] D86135
- [confirmed] The `__VA_ARGS__` and other macro nitty-gritty, such as how to
stringify macro parameters, where to put or swallow commas, etc. are not
handled correctly.
- [confirmed] Unbalanced parenthesis are not well handled - resulting in
incorrect expansions or even crashes.
- [confirmed][crashing] https://bugs.llvm.org/show_bug.cgi?id=48358
Reviewed By: martong, Szelethus
Differential Revision: https://reviews.llvm.org/D93222
This patch extracts the ExprMutAnalyzer changes from https://reviews.llvm.org/D54943
into its own revision for simpler review and more atomic changes.
The analysis results are improved. Nested expressions (e.g. conditional
operators) are now detected properly. Some edge cases, especially
template induced imprecisions are improved upon.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D88088
This reverts commit 97aa593a83 as it
causes problems (PR45453) https://reviews.llvm.org/D77574#1966321.
This additionally adds an explicit reference to FrontendOpenMP to
clang-tidy where ASTMatchers is used.
This is hopefully just a temporary solution. The dependence on
`FrontendOpenMP` from `ASTMatchers` should be handled by CMake
implicitly, not us explicitly.
Reviewed By: aheejin
Differential Revision: https://reviews.llvm.org/D77666
Summary:
ASTMatchers is used in various places and it now exposes the
LLVMFrontendOpenMP library to its users without them needing to depend
on it explicitly.
Reviewers: lebedev.ri
Subscribers: mgorny, yaxunl, bollu, guansong, martong, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D77574
Move the listing of allowed clauses per OpenMP directive to the new
macro file in `llvm/Frontend/OpenMP`. Also, use a single generic macro
that specifies the directive and one allowed clause explicitly instead
of a dedicated macro per directive.
We save 800 loc and boilerplate for all new directives/clauses with no
functional change. We also need to include the macro file only once and
not once per directive.
Depends on D77112.
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D77113
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.
Right now every dataflow algorithm uses its own worklist implementation.
This is a first step to reduce this duplication. Some upcoming
algorithms such as the lifetime analysis is going to use the factored
out implementations.
Differential Revision: https://reviews.llvm.org/D72380
The CFGBlock::getLastCondition was not prepared for static initializer
branches.
This patch also revamps CFG unit tests. Earlier the lifetime of the AST
was smaller than the CFG. So all the AST pointers within the CFG blocks
were dangling. This was OK, since none of the tests dereferenced those
pointers. This was, however, a timed bomb. There were patches in the
past that were reverted partially due to this problem.
Differential revision: https://reviews.llvm.org/D71791
Previously, collecting CFGElements in a set was practially impossible, because
both CFGBlock::operator[] and both the iterators returned it by value. One
workaround would be to collect the iterators instead, but they don't really
capture the concept of an element, and elements from different iterator types are incomparable.
This patch introduces CFGElementRef, a wrapper around a (CFGBlock, Index) pair,
and a variety of new iterators and iterator ranges to solve this problem.
I guess you could say that this patch took a couple iterations to get right :^)
Differential Revision: https://reviews.llvm.org/D65196
llvm-svn: 368883
I intend to improve the analyzer's bug reports by tracking condition
expressions.
01 bool b = messyComputation();
02 int i = 0;
03 if (b) // control dependency of the bug site, let's explain why we assume val
04 // to be true
05 10 / i; // warn: division by zero
I'll detail this heuristic in the followup patch, strictly related to this one
however:
* Create the new ControlDependencyCalculator class that uses llvm::IDFCalculator
to (lazily) calculate control dependencies for Clang's CFG.
* A new debug checker debug.DumpControlDependencies is added for lit tests
* Add unittests
Differential Revision: https://reviews.llvm.org/D62619
llvm-svn: 365197
getTerminatorCondition() returned a condition that may be outside of the
block, while the new function returns the proper one:
if (A && B && C) {}
Return C instead of A && B && C.
Differential Revision: https://reviews.llvm.org/D63538
llvm-svn: 365177
Currently we always inline functions that have no branches, i.e. have exactly
three CFG blocks: ENTRY, some code, EXIT. This makes sense because when there
are no branches, it means that there's no exponential complexity introduced
by inlining such function. Such functions also don't trigger various fundamental
problems with our inlining mechanism, such as the problem of inlined
defensive checks.
Sometimes the CFG may contain more blocks, but in practice it still has
linear structure because all directions (except, at most, one) of all branches
turned out to be unreachable. When this happens, still treat the function
as "small". This is useful, in particular, for dealing with C++17 if constexpr.
Differential Revision: https://reviews.llvm.org/D61051
llvm-svn: 359531
We should track mutation of a variable within a comma operator expression.
Current code in ExprMutationAnalyzer does not handle it.
This will handle cases like:
(a, b) ++ < == b is modified
(a, b) = c < == b is modifed
Patch by Djordje Todorovic.
Differential Revision: https://reviews.llvm.org/D58894
llvm-svn: 355605
Summary:
This patch adds two unit-tests that are the result of reducing a crashing TU
when running ExprMutAnalyzer over it. They are added only to ensure the regression
that has been fixed with https://reviews.llvm.org/D56444 don't creep back.
Reviewers: aaron.ballman, sammccall, rsmith, george.karpenkov
Reviewed By: sammccall
Subscribers: baloghadamsoftware, a.sidorin, Szelethus, donat.nagy, dkrupp, cfe-commits
Differential Revision: https://reviews.llvm.org/D56917
llvm-svn: 351743
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
Summary:
`buildASTFromCodeWithArgs()` was creating a memory buffer referencing a
stack-allocated string. This diff changes the implementation to copy the code
string into the memory buffer so that said buffer owns the memory.
Patch by Yitzhak Mandelbaum.
Reviewers: alexfh
Reviewed By: alexfh
Subscribers: cfe-commits, EricWF
Differential Revision: https://reviews.llvm.org/D55765
llvm-svn: 350638
This is a more thorough fix of rC348911.
The story about -DBUILD_SHARED_LIBS=on build after rC348907 (Move PCHContainerOperations from Frontend to Serialization) is:
1. libclangSerialization.so defines PCHContainerReader dtor, ...
2. clangFrontend and clangTooling define classes inheriting from PCHContainerReader, thus their DSOs have undefined references on PCHContainerReader dtor
3. Components depending on either clangFrontend or clangTooling cannot be linked unless they have explicit dependency on clangSerialization due to the default linker option -z defs. The explicit dependency could be avoided if libclang{Frontend,Tooling}.so had these undefined references.
This patch adds the explicit dependency on clangSerialization to make them build.
llvm-svn: 348915
Summary:
This is a follow up of D52008 and should make the analyzer being able to handle perfect forwardings in real world cases where forwardings are done through multiple layers of function calls with `std::forward`.
Fixes PR38891.
Reviewers: lebedev.ri, JonasToth, george.karpenkov
Subscribers: xazax.hun, szepet, a.sidorin, mikhail.ramalho, Szelethus, cfe-commits
Differential Revision: https://reviews.llvm.org/D52120
llvm-svn: 342409
Summary:
We used to treat an `Expr` mutated whenever it's passed as non-const
reference argument to a function. This results in false positives in
cases like this:
```
int x;
std::vector<int> v;
v.emplace_back(x); // `x` is passed as non-const reference to `emplace_back`
```
In theory the false positives can be suppressed with
`v.emplace_back(std::as_const(x))` but that's considered overly verbose,
inconsistent with existing code and spammy as diags.
This diff handles such cases by following into the function definition
and see whether the argument is mutated inside.
Reviewers: lebedev.ri, JonasToth, george.karpenkov
Subscribers: xazax.hun, szepet, a.sidorin, mikhail.ramalho, Szelethus, cfe-commits
Differential Revision: https://reviews.llvm.org/D52008
llvm-svn: 342271
Summary:
This is 1/2 of moving ExprMutationAnalyzer from clangtidy to
clang/Analysis.
This diff along simply copies the ExprMutationAnalyzer over with trivial
modifications (e.g. include path, namespace)
2/2 will migrate existing usage of ExprMutationAnalyzer and remove the
original copy inside clangtidy.
Reviewers: george.karpenkov
Subscribers: mgorny, xazax.hun, szepet, a.sidorin, mikhail.ramalho, Szelethus, cfe-commits, JonasToth
Differential Revision: https://reviews.llvm.org/D51948
llvm-svn: 341994
We currently use target_link_libraries without an explicit scope
specifier (INTERFACE, PRIVATE or PUBLIC) when linking executables.
Dependencies added in this way apply to both the target and its
dependencies, i.e. they become part of the executable's link interface
and are transitive.
Transitive dependencies generally don't make sense for executables,
since you wouldn't normally be linking against an executable. This also
causes issues for generating install export files when using
LLVM_DISTRIBUTION_COMPONENTS. For example, clang has a lot of LLVM
library dependencies, which are currently added as interface
dependencies. If clang is in the distribution components but the LLVM
libraries it depends on aren't (which is a perfectly legitimate use case
if the LLVM libraries are being built static and there are therefore no
run-time dependencies on them), CMake will complain about the LLVM
libraries not being in export set when attempting to generate the
install export file for clang. This is reasonable behavior on CMake's
part, and the right thing is for LLVM's build system to explicitly use
PRIVATE dependencies for executables.
Unfortunately, CMake doesn't allow you to mix and match the keyword and
non-keyword target_link_libraries signatures for a single target; i.e.,
if a single call to target_link_libraries for a particular target uses
one of the INTERFACE, PRIVATE, or PUBLIC keywords, all other calls must
also be updated to use those keywords. This means we must do this change
in a single shot. I also fully expect to have missed some instances; I
tested by enabling all the projects in the monorepo (except dragonegg),
and configuring both with and without shared libraries, on both Darwin
and Linux, but I'm planning to rely on the buildbots for other
configurations (since it should be pretty easy to fix those).
Even after this change, we still have a lot of target_link_libraries
calls that don't specify a scope keyword, mostly for shared libraries.
I'm thinking about addressing those in a follow-up, but that's a
separate change IMO.
Differential Revision: https://reviews.llvm.org/D40823
llvm-svn: 319840
Summary:
This patch aims at optimizing the CloneChecker for larger programs. Before this
patch we took around 102 seconds to analyze sqlite3 with a complexity value of
50. After this patch we now take 2.1 seconds to analyze sqlite3.
The biggest performance optimization is that we now put the constraint for group
size before the constraint for the complexity. The group size constraint is much
faster in comparison to the complexity constraint as it only does a simple
integer comparison. The complexity constraint on the other hand actually
traverses each Stmt and even checks the macro stack, so it is obviously not able
to handle larger amounts of incoming clones. The new order filters out all the
single-clone groups that the type II constraint generates in a faster way before
passing the fewer remaining clones to the complexity constraint. This reduced
runtime by around 95%.
The other change is that we also delay the verification part of the type II
clones back in the chain of constraints. This required to split up the
constraint into two parts - a verification and a hash constraint (which is also
making it more similar to the original design of the clone detection algorithm).
The reasoning for this is the same as before: The verification constraint has to
traverse many statements and shouldn't be at the start of the constraint chain.
However, as the type II hashing has to be the first step in our algorithm, we
have no other choice but split this constrain into two different ones. Now our
group size and complexity constrains filter out a chunk of the clones before
they reach the slow verification step, which reduces the runtime by around 8%.
I also kept the full type II constraint around - that now just calls it's two
sub-constraints - in case someone doesn't care about the performance benefits
of doing this.
Reviewers: NoQ
Reviewed By: NoQ
Subscribers: klimek, v.g.vassilev, xazax.hun, cfe-commits
Differential Revision: https://reviews.llvm.org/D34182
llvm-svn: 312222
Hopefully fix crashes by unshadowing the variable.
Original commit message:
A big part of the clone detection code is functionality for filtering clones and
clone groups based on different criteria. So far this filtering process was
hardcoded into the CloneDetector class, which made it hard to understand and,
ultimately, to extend.
This patch splits the CloneDetector's logic into a sequence of reusable
constraints that are used for filtering clone groups. These constraints
can be turned on and off and reodreder at will, and new constraints are easy
to implement if necessary.
Unit tests are added for the new constraint interface.
This is a refactoring patch - no functional change intended.
Patch by Raphael Isemann!
Differential Revision: https://reviews.llvm.org/D23418
llvm-svn: 299653
A big part of the clone detection code is functionality for filtering clones and
clone groups based on different criteria. So far this filtering process was
hardcoded into the CloneDetector class, which made it hard to understand and,
ultimately, to extend.
This patch splits the CloneDetector's logic into a sequence of reusable
constraints that are used for filtering clone groups. These constraints
can be turned on and off and reodreder at will, and new constraints are easy
to implement if necessary.
Unit tests are added for the new constraint interface.
This is a refactoring patch - no functional change intended.
Patch by Raphael Isemann!
Differential Revision: https://reviews.llvm.org/D23418
llvm-svn: 299544
Summary:
I've included a unit test with a function template containing a variable
of incomplete type. Clang compiles this without errors (the standard
does not require a diagnostic in this case). Without the fix, this case
triggers the crash.
Reviewers: klimek
Reviewed By: klimek
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D30636
llvm-svn: 297129
Summary:
CXXDeleteExpr::getDestroyedType() can return a null QualType if the destroyed
type is a dependent type. This patch protects against this.
Reviewers: klimek
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D27350
llvm-svn: 288665
Summary:
CFG generation is expected to fail in this case, but it should not crash.
Also added a test that reproduces the crash.
Reviewers: klimek
Subscribers: cfe-commits
Patch by Martin Boehme!
Differential Revision: http://reviews.llvm.org/D21895
llvm-svn: 274834
Benjamin Kramer