Commit Graph

17 Commits

Author SHA1 Message Date
Balazs Benics 96ccb690a0 [analyzer][NFC] Prefer using isa<> instead getAs<> in conditions
Depends on D125709

Reviewed By: martong

Differential Revision: https://reviews.llvm.org/D127742
2022-06-15 16:58:13 +02:00
Balazs Benics f1b18a79b7 [analyzer][NFC] Remove dead code and modernize surroundings
Thanks @kazu for helping me clean these parts in D127799.

I'm leaving the dump methods, along with the unused visitor handlers and
the forwarding methods.

The dead parts actually helped to uncover two bugs, to which I'm going
to post separate patches.

Reviewed By: martong

Differential Revision: https://reviews.llvm.org/D127836
2022-06-15 16:50:12 +02:00
Balazs Benics 0b9d3a6e53 [analyzer][NFC] Separate CallDescription from CallEvent
`CallDescriptions` deserve its own translation unit.
This patch simply moves the corresponding parts.
Also includes the `CallDescription.h` where it's necessary.

Reviewed By: martong, xazax.hun, Szelethus

Differential Revision: https://reviews.llvm.org/D113587
2021-11-15 19:10:46 +01:00
Endre Fülöp 141cb8a1ee [analyzer] Model iterator random incrementation symmetrically
Summary:
In case a pointer iterator is incremented in a binary plus expression
(operator+), where the iterator is on the RHS, IteratorModeling should
now detect, and track the resulting value.

Reviewers: Szelethus, baloghadamsoftware

Reviewed By: baloghadamsoftware

Subscribers: rnkovacs, whisperity, xazax.hun, baloghadamsoftware, szepet, a.sidorin, mikhail.ramalho, Szelethus, donat.nagy, dkrupp, Charusso, steakhal, martong, ASDenysPetrov, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D83190
2020-08-04 11:04:12 +02:00
Adam Balogh a59d4ae431 [Analyzer] Hotfix for various crashes in iterator checkers
The patch that introduces handling iterators implemented as pointers may
cause crash in some projects because pointer difference is mistakenly
handled as pointer decrement. (Similair case for iterators implemented
as class instances are already handled correctly.) This patch fixes this
issue.

The second case that causes crash is comparison of an iterator
implemented as pointer and a null-pointer. This patch contains a fix for
this issue as well.

The third case which causes crash is that the checker mistakenly
considers all integers as nonloc::ConcreteInt when handling an increment
or decrement of an iterator implemented as pointers. This patch adds a
fix for this too.

The last case where crashes were detected is when checking for success
of an std::advance() operation. Since the modeling of iterators
implemented as pointers is still incomplete this may result in an
assertion. This patch replaces the assertion with an early exit and
adds a FIXME there.

Differential Revision: https://reviews.llvm.org/D83295
2020-07-16 20:49:33 +02:00
Adam Balogh 9e63b190af [Analyzer] Handle pointer implemented as iterators in iterator checkers
Iterators are an abstraction of pointers and in some data structures
iterators may be implemented by pointers. This patch adds support for
iterators implemented as pointers in all the iterator checkers
(including iterator modeling).

Differential Revision: https://reviews.llvm.org/D82185
2020-07-01 09:04:28 +02:00
Adam Balogh ea563daae5 [Analyzer] Fix errors in iterator modeling
There is major a bug found in iterator modeling: upon adding a value
to or subtracting a value from an iterator the position of the original
iterator is also changed beside the result. This patch fixes this bug.

To catch such bugs in the future we also changed the tests to look for
regular expressions including an end-of-line symbol (`$`) so we can
prevent false matches where only the tested prefix matches.

Another minor bug is that when printing the state, all the iterator
positions are printed in a single line. This patch also fixes this.

Differential Revision: https://reviews.llvm.org/D82385
2020-07-01 09:04:28 +02:00
Denys Petrov ba8cda989c [analyzer] Stability improvement for IteratorModeling
Summary:
Some function path may lead to crash.
Fixed using local variable outside the scope  through a pointer.
Fixed minor misspellings.
Added regression test.

This patch covers a bug https://bugs.llvm.org/show_bug.cgi?id=41485

Reviewed By: baloghadamsoftware

Differential Revision: https://reviews.llvm.org/D78289
2020-05-06 14:16:39 +03:00
Kirstóf Umann bda3dd0d98 [analyzer][NFC] Change LangOptions to CheckerManager in the shouldRegister* functions
Some checkers may not only depend on language options but also analyzer options.
To make this possible this patch changes the parameter of the shouldRegister*
function to CheckerManager to be able to query the analyzer options when
deciding whether the checker should be registered.

Differential Revision: https://reviews.llvm.org/D75271
2020-03-27 14:34:09 +01:00
Adam Balogh 60bad941a1 [Analyzer] Iterator Modeling - Model `std::advance()`, `std::prev()` and `std::next()`
Whenever the analyzer budget runs out just at the point where
`std::advance()`, `std::prev()` or `std::next()` is invoked the function
are not inlined. This results in strange behavior such as
`std::prev(v.end())` equals `v.end()`. To prevent this model these
functions if they were not inlined. It may also happend that although
`std::advance()` is inlined but a function it calls inside (e.g.
`__advance()` in some implementations) is not. This case is also handled
in this patch.

Differential Revision: https://reviews.llvm.org/D76361
2020-03-23 15:29:55 +01:00
Adam Balogh b198f16e1e [Analyzer] Model STL Algoirthms to improve the iterator checkers
STL Algorithms are usually implemented in a tricky for performance
reasons which is too complicated for the analyzer. Furthermore inlining
them is costly. Instead of inlining we should model their behavior
according to the specifications.

This patch is the first step towards STL Algorithm modeling. It models
all the `find()`-like functions in a simple way: the result is either
found or not. In the future it can be extended to only return success if
container modeling is also extended in a way the it keeps track of
trivial insertions and deletions.

Differential Revision: https://reviews.llvm.org/D70818
2020-02-05 17:59:08 +01:00
Adam Balogh 9a08a3fab9 [Analyzer] Split container modeling from iterator modeling
Iterator modeling depends on container modeling,
but not vice versa. This enables the possibility
to arrange these two modeling checkers into
separate layers.

There are several advantages for doing this: the
first one is that this way we can keep the
respective modeling checkers moderately simple
and small. Furthermore, this enables creation of
checkers on container operations which only
depend on the container modeling. Thus iterator
modeling can be disabled together with the
iterator checkers if they are not needed.

Since many container operations also affect
iterators, container modeling also uses the
iterator library: it creates iterator positions
upon calling the `begin()` or `end()` method of
a containter (but propagation of the abstract
position is left to the iterator modeling),
shifts or invalidates iterators according to the
rules upon calling a container modifier and
rebinds the iterator to a new container upon
`std::move()`.

Iterator modeling propagates the abstract
iterator position, handles the relations between
iterator positions and models iterator
operations such as increments and decrements.

Differential Revision: https://reviews.llvm.org/D73547
2020-01-29 16:10:45 +01:00
Mark de Wever b6d9e97662 [Analyzer] Fixes -Wrange-loop-analysis warnings
This avoids new warnings due to D68912 adds -Wrange-loop-analysis to -Wall.

Differential Revision: https://reviews.llvm.org/D71809
2019-12-22 19:13:34 +01:00
Mark de Wever 70d592d68c [Analyzer] Use a reference in a range-based for
This avoids unneeded copies when using a range-based for loops.

This avoids new warnings due to D68912 adds -Wrange-loop-analysis to -Wall.

Differential Revision: https://reviews.llvm.org/D70869
2019-12-21 14:52:29 +01:00
Adam Balogh 855d21a03a [Analyzer] Iterator Checkers: Replace `UnknownVal` in comparison result by a conjured value
Sometimes the return value of a comparison operator call is
`UnkownVal`. Since no assumptions can be made on `UnknownVal`,
this leeds to keeping impossible execution paths in the
exploded graph resulting in poor performance and false
positives. To overcome this we replace unknown results of
iterator comparisons by conjured symbols.

Differential Revision: https://reviews.llvm.org/D70244
2019-12-11 15:24:06 +01:00
Adam Balogh 6e9c58946e [Analyzer] Iterator Modeling: Print Container Data and Iterator Positions when printing the Program State
Debugging the Iterator Modeling checker or any of the iterator checkers
is difficult without being able to see the relations between the
iterator variables and their abstract positions, as well as the abstract
symbols denoting the begin and the end of the container.

This patch adds the checker-specific part of the Program State printing
to the Iterator Modeling checker.
2019-12-11 14:20:17 +01:00
Adam Balogh afb13afcf2 [Analyzer][NFC] Iterator Checkers - Separate iterator modeling and the actual checkers
A monolithic checker class is hard to maintain. This patch splits it up
into a modeling part, the three checkers and a debug checker. The common
functions are moved into a library.

Differential Revision: https://reviews.llvm.org/D70320
2019-12-11 13:06:19 +01:00