Commit Graph

467 Commits

Author SHA1 Message Date
Nick Desaulniers 3a604fdbcd [Clang][CFG] check children statements of asm goto
When performing CFG based analyses, don't forget to check the child
statements of an asm goto, such as the expressions used for
inputs+outputs.

Fixes: https://github.com/llvm/llvm-project/issues/51024
Fixes: https://github.com/ClangBuiltLinux/linux/issues/1439

Reviewed By: void, jyknight, jyu2, efriedma

Differential Revision: https://reviews.llvm.org/D116059
2022-01-07 14:11:08 -08:00
Kazu Hirata d677a7cb05 [clang] Remove redundant member initialization (NFC)
Identified with readability-redundant-member-init.
2022-01-02 10:20:23 -08:00
Kazu Hirata 2d303e6781 Remove redundant return and continue statements (NFC)
Identified with readability-redundant-control-flow.
2021-12-24 23:17:54 -08:00
Kazu Hirata eb1c7c1339 [AST, Analysis] Use llvm::reverse (NFC) 2021-11-07 09:53:14 -08:00
Nico Weber c7aaa2efef [clang] Add range accessor for ObjCAtTryStmt catch_stmts and use it
No behavior change.

Differential Revision: https://reviews.llvm.org/D112543
2021-10-27 08:57:05 -04:00
Nico Weber 04f30795f1 [clang] Implement CFG construction for @try and @catch
@finally is still not implemented.

With this, clang can emit -Wreturn-type warnings for functions containing
@try/@catch (but not yet @finally), and -Wunreachable-code also works for those
functions.

The implementation is similar to D36914.

Part of PR46693.

Differential Revision: https://reviews.llvm.org/D112287
2021-10-26 09:45:22 -04:00
Nico Weber 0b7c9addce [clang] Make loop in CFGBuilder::VisitCXXTryStmt() more canonical
No behavior change.
2021-10-26 09:45:22 -04:00
Nico Weber aa42785d01 [clang] Simplify CFG block printing code a bit
No behavior change.
2021-10-26 09:45:22 -04:00
Nico Weber d054b31d59 [clang] Use consistent punctuation at end of Block NULL comment
No behavior change.
2021-10-26 09:45:22 -04:00
Kazu Hirata 4bd46501c3 Use llvm::any_of and llvm::none_of (NFC) 2021-10-24 17:35:33 -07:00
Nico Weber c74ab84ea2 [clang] Omit most AttributedStatements from the CFG
`[[clang::fallthrough]]` has meaning for the CFG, but all other
StmtAttrs we currently have don't. So omit them, as AttributedStatements
with children cause several issues and there's no benefit in including
them.

Fixes PR52103 and PR49454. See PR52103 for details.

Differential Revision: https://reviews.llvm.org/D111568
2021-10-12 09:15:45 -04:00
Nico Weber 5ab2a95edb [clang] Remove an else-after-return 2021-10-11 14:24:58 -04:00
Nico Weber 00ca004dda [clang] Convert a few loops to for-each 2021-10-11 14:24:32 -04:00
Nico Weber 144f851f6f [clang/CFG] Rewrap a line to 80 columns 2021-10-11 14:23:51 -04:00
Corentin Jabot 424733c12a Implement if consteval (P1938)
Modify the IfStmt node to suppoort constant evaluated expressions.

Add a new ExpressionEvaluationContext::ImmediateFunctionContext to
keep track of immediate function contexts.

This proved easier/better/probably more efficient than walking the AST
backward as it allows diagnosing nested if consteval statements.
2021-10-05 08:04:14 -04:00
Tomasz Kamiński 058f384ae9 [analyzer] Correctly propagate ConstructionContextLayer thru ParenExpr
Previously, information about `ConstructionContextLayer` was not
propagated thru causing the expression like:

  Var c = (createVar());

To produce unrelated temporary for the `createVar()` result and conjure
a new symbol for the value of `c` in C++17 mode.

Reviewed By: steakhal

Patch By: tomasz-kaminski-sonarsource!

Differential Revision: https://reviews.llvm.org/D102835
2021-05-24 10:16:52 +02:00
James Y Knight 8f670d5b6d CFG: Create scope for non-compound range-for body.
Previously, it was omitting the destructor call from the CFG, which
could result in incorrect diagnostics.
2021-01-31 18:43:00 -05:00
Thorsten Schütt 2fd11e0b1e Revert "[NFC, Refactor] Modernize StorageClass from Specifiers.h to a scoped enum (II)"
This reverts commit efc82c4ad2.
2021-01-04 23:17:45 +01:00
Thorsten Schütt efc82c4ad2 [NFC, Refactor] Modernize StorageClass from Specifiers.h to a scoped enum (II)
Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D93765
2021-01-04 22:58:26 +01:00
Alexey Bataev 4a7aedb843 [OPENMP]Simplify representation for atomic, critical, master and section
constrcut.

Several constructs may be represented wityout relying on CapturedStmt.
It saves memory and improves compilation speed.
2020-08-07 09:58:23 -04:00
Richard Smith 076b120beb CFG: Destroy temporaries in (a,b) expression in the correct order. 2020-08-05 14:52:53 -07:00
Richard Smith 4ccb6c36a9 Fix violations of [basic.class.scope]p2.
These cases all follow the same pattern:

struct A {
  friend class X;
  //...
  class X {};
};

But 'friend class X;' injects 'X' into the surrounding namespace scope,
rather than introducing a class member. So the second 'class X {}' is a
completely different type, which changes the meaning of the earlier name
'X' from '::X' to 'A::X'.

Additionally, the friend declaration is pointless -- members of a class
don't need to be befriended to be able to access private members.
2020-06-01 22:03:05 -07:00
Balázs Kéri 3b9b3d56ef [Analyzer] Include typedef statements in CFG build.
Summary:
Array size expressions in typedef statements with a VLA
(variable-length array) are handled from now as in plain
(non-typedef) VLA declarations.
Type-aliases with VLA are handled too
(but main focus is on C code).

Reviewers: Szelethus, aaron.ballman, NoQ, xazax.hun

Reviewed By: aaron.ballman, xazax.hun

Subscribers: rnkovacs, NoQ, efriedma, xazax.hun, baloghadamsoftware, szepet, a.sidorin, mikhail.ramalho, Szelethus, donat.nagy, dkrupp, gamesh411, Charusso, martong, ASDenysPetrov, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D77809
2020-04-27 12:36:26 +02:00
Justin Lebar f0fd852fcd Fix SFINAE in CFG.cpp.
Summary: Used std::enable_if without ::type.

Reviewers: bkramer, MaskRay

Subscribers: martong, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D74412
2020-02-11 10:37:08 -08:00
Gabor Horvath 379613d7c7 [CFG] Fix an assertion failure with static initializers
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
2019-12-23 16:35:37 -08:00
Gabor Horvath ea93d7d642 [CFG] Add an option to expand CXXDefaultInitExpr into aggregate initialization
This is useful for clients that are relying on linearized CFGs for evaluating
subexpressions and want the default initializer to be evaluated properly.

The upcoming lifetime analysis is using this but it might also be useful
for the static analyzer at some point.

Differential Revision: https://reviews.llvm.org/D71642
2019-12-17 17:56:06 -08:00
Gabor Horvath 9fdcae7c81 [analyzer] Do not cache out on some shared implicit AST nodes
Some AST nodes which stands for implicit initialization is shared. The analyzer
will do the same evaluation on the same nodes resulting in the same state. The
analyzer will "cache out", i.e. it thinks that it visited an already existing
node in the exploded graph. This is not true in this case and we lose coverage.
Since these nodes do not really require any processing from the analyzer
we just omit them from the CFG.

Differential Revision: https://reviews.llvm.org/D71371
2019-12-11 17:15:12 -08:00
Artem Dergachev a3b22da4e0 [CFG] Fix a flaky crash in CFGBlock::getLastCondition().
Using an end iterator of an empty CFG block was causing
a garbage pointer dereference.

Differential Revision: https://reviews.llvm.org/D69962
2019-11-21 21:55:58 -08:00
Tyker b0561b3346 [NFC] Refactor representation of materialized temporaries
Summary:
this patch refactor representation of materialized temporaries to prevent an issue raised by rsmith in https://reviews.llvm.org/D63640#inline-612718

Reviewers: rsmith, martong, shafik

Reviewed By: rsmith

Subscribers: thakis, sammccall, ilya-biryukov, rnkovacs, arphaman, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D69360
2019-11-19 18:20:45 +01:00
Nico Weber c9276fbfdf Revert "[NFC] Refactor representation of materialized temporaries"
This reverts commit 08ea1ee2db.
It broke ./ClangdTests/FindExplicitReferencesTest.All
on the bots, see comments on https://reviews.llvm.org/D69360
2019-11-17 02:09:25 -05:00
Tyker 08ea1ee2db [NFC] Refactor representation of materialized temporaries
Summary:
this patch refactor representation of materialized temporaries to prevent an issue raised by rsmith in https://reviews.llvm.org/D63640#inline-612718

Reviewers: rsmith, martong, shafik

Reviewed By: rsmith

Subscribers: rnkovacs, arphaman, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D69360
2019-11-16 17:56:09 +01:00
Richard Trieu 8b0d14a8f0 New tautological warning for bitwise-or with non-zero constant always true.
Taking a value and the bitwise-or it with a non-zero constant will always
result in a non-zero value. In a boolean context, this is always true.

if (x | 0x4) {}  // always true, intended '&'

This patch creates a new warning group -Wtautological-bitwise-compare for this
warning. It also moves in the existing tautological bitwise comparisons into
this group. A few other changes were needed to the CFGBuilder so that all bool
contexts would be checked. The warnings in -Wtautological-bitwise-compare will
be off by default due to using the CFG.

Fixes: https://bugs.llvm.org/show_bug.cgi?id=42666
Differential Revision: https://reviews.llvm.org/D66046

llvm-svn: 375318
2019-10-19 00:57:23 +00:00
Alexey Bataev 9c5d76ff4d [OPENMP]Dow not emit warnings for uninitialized loop counters.
In OpenMP constructs all counters are initialized and we should not emit
warnings about uninitialized privatized loop control variables.

llvm-svn: 375167
2019-10-17 20:35:08 +00:00
Richard Trieu 4c05de8c1d Merge and improve code that detects same value in comparisons.
-Wtautological-overlap-compare and self-comparison from -Wtautological-compare
relay on detecting the same operand in different locations.  Previously, each
warning had it's own operand checker.  Now, both are merged together into
one function that each can call.  The function also now looks through member
access and array accesses.

Differential Revision: https://reviews.llvm.org/D66045

llvm-svn: 372453
2019-09-21 03:02:26 +00:00
Richard Trieu 6541c7988b Improve -Wtautological-overlap-compare
Allow this warning to detect a larger number of constant values, including
negative numbers, and handle non-int types better.

Differential Revision: https://reviews.llvm.org/D66044

llvm-svn: 372448
2019-09-21 02:37:10 +00:00
Kristof Umann f174670efa [CFG] Add dumps for CFGElement and CFGElementRef
Seems like we never had these, so here we go! I also did some refactoring as I
was chasing a bug unrelated to this revision.

Differential Revision: https://reviews.llvm.org/D66715

llvm-svn: 371765
2019-09-12 19:52:34 +00:00
Artem Dergachev e5c0994ddf [CFG] Fix CFG for statement-expressions in return values.
We're building the CFG from bottom to top, so when the return-value expression
has a non-trivial CFG on its own, we need to continue building from the entry
to the return-value expression CFG rather than from the block to which
we've just appended the return statement.

Fixes a false positive warning "control may reach end of non-void function".

llvm-svn: 370406
2019-08-29 20:37:28 +00:00
Artem Dergachev 3517d10575 [analyzer] Fix more analyzer warnings on analyzer and libAnalysis.
llvm-svn: 370263
2019-08-28 21:19:58 +00:00
Artem Dergachev ead98ea3eb [CFG] Make representation of destructor calls more accurate.
Respect C++17 copy elision; previously it would generate destructor calls
for elided temporaries, including in initialization and return statements.

Don't generate duplicate destructor calls for statement expressions.

Fix destructors in initialization lists and comma operators.

Improve printing of implicit destructors.

Patch by Nicholas Allegra!

Differential Revision: https://reviews.llvm.org/D66404

llvm-svn: 370247
2019-08-28 18:44:42 +00:00
Kristof Umann 92541e359e [CFG] Introduce CFGElementRef, a wrapper that knows it's position in a CFGBlock
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
2019-08-14 17:05:55 +00:00
Kristof Umann dd53bdbfde [analyzer][CFG] Don't track the condition of asserts
Well, what is says on the tin I guess!

Some more changes:

* Move isInevitablySinking() from BugReporter.cpp to CFGBlock's interface
* Rename and move findBlockForNode() from BugReporter.cpp to
ExplodedNode::getCFGBlock()

Differential Revision: https://reviews.llvm.org/D65287

llvm-svn: 368836
2019-08-14 12:20:08 +00:00
Rui Ueyama 4d41c332ef Revert r367649: Improve raw_ostream so that you can "write" colors using operator<<
This reverts commit r367649 in an attempt to unbreak Windows bots.

llvm-svn: 367658
2019-08-02 07:22:34 +00:00
Rui Ueyama a52f982f1c Improve raw_ostream so that you can "write" colors using operator<<
1. raw_ostream supports ANSI colors so that you can write messages to
the termina with colors. Previously, in order to change and reset
color, you had to call `changeColor` and `resetColor` functions,
respectively.

So, if you print out "error: " in red, for example, you had to do
something like this:

  OS.changeColor(raw_ostream::RED);
  OS << "error: ";
  OS.resetColor();

With this patch, you can write the same code as follows:

  OS << raw_ostream::RED << "error: " << raw_ostream::RESET;

2. Add a boolean flag to raw_ostream so that you can disable colored
output. If you disable colors, changeColor, operator<<(Color),
resetColor and other color-related functions have no effect.

Most LLVM tools automatically prints out messages using colors, and
you can disable it by passing a flag such as `--disable-colors`.
This new flag makes it easy to write code that works that way.

Differential Revision: https://reviews.llvm.org/D65564

llvm-svn: 367649
2019-08-02 04:48:30 +00:00
Alexey Bataev 655cb4a2d7 [OPENMP]Add support for analysis of if clauses.
Summary:
Added support for analysis of if clauses in the OpenMP directives to be
able to check for the use of uninitialized variables.

Reviewers: NoQ

Subscribers: guansong, jfb, jdoerfert, caomhin, kkwli0, cfe-commits

Tags: clang

Differential Revision: https://reviews.llvm.org/D64646

llvm-svn: 366211
2019-07-16 14:51:46 +00:00
Rui Ueyama 49a3ad21d6 Fix parameter name comments using clang-tidy. NFC.
This patch applies clang-tidy's bugprone-argument-comment tool
to LLVM, clang and lld source trees. Here is how I created this
patch:

$ git clone https://github.com/llvm/llvm-project.git
$ cd llvm-project
$ mkdir build
$ cd build
$ cmake -GNinja -DCMAKE_BUILD_TYPE=Debug \
    -DLLVM_ENABLE_PROJECTS='clang;lld;clang-tools-extra' \
    -DCMAKE_EXPORT_COMPILE_COMMANDS=On -DLLVM_ENABLE_LLD=On \
    -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++ ../llvm
$ ninja
$ parallel clang-tidy -checks='-*,bugprone-argument-comment' \
    -config='{CheckOptions: [{key: StrictMode, value: 1}]}' -fix \
    ::: ../llvm/lib/**/*.{cpp,h} ../clang/lib/**/*.{cpp,h} ../lld/**/*.{cpp,h}

llvm-svn: 366177
2019-07-16 04:46:31 +00:00
Alexey Bataev c2c21ef9d2 [OPENMP]Initial fix PR42392: Improve -Wuninitialized warnings for OpenMP programs.
Summary:
Some OpenMP clauses rely on the values of the variables. If the variable
is not initialized and used in OpenMP clauses that depend on the
variables values, it should be reported that the uninitialized variable
is used in the OpenMP clause expression.
This patch adds initial processing for uninitialized variables in OpenMP
constructs. Currently, it checks for use of the uninitialized variables
in the structured blocks.

Reviewers: NoQ, Szelethus, dcoughlin, xazax.hun, a.sidorin, george.karpenkov, szepet

Subscribers: rnkovacs, guansong, jfb, jdoerfert, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D64356

llvm-svn: 365786
2019-07-11 14:54:17 +00:00
Kristof Umann d5c9d9b682 [CFG] Add a new function to get the proper condition of a CFGBlock
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
2019-07-05 09:52:00 +00:00
Kristof Umann 9854d771bd Revert "[analyzer][CFG] Return the correct terminator condition"
This reverts commit 7a57118a6fcfa3770f984453543bbdfd0b233e84.

Causes a bunch of crashes, I need to time to evaluate this.

llvm-svn: 365037
2019-07-03 13:03:33 +00:00
Kristof Umann 00aab1d45e [analyzer][CFG] Return the correct terminator condition
For the following terminator statement:

if (A && B && C && D)
The built CFG is the following:

[B5 (ENTRY)]
  Succs (1): B4

[B1]
  1: 10
  2: j
  3: [B1.2] (ImplicitCastExpr, LValueToRValue, int)
  4: [B1.1] / [B1.3]
  5: int x = 10 / j;
  Preds (1): B2
  Succs (1): B0

[B2]
  1: C
  2: [B2.1] (ImplicitCastExpr, LValueToRValue, _Bool)
  T: if [B4.4] && [B3.2] && [B2.2]
  Preds (1): B3
  Succs (2): B1 B0

[B3]
  1: B
  2: [B3.1] (ImplicitCastExpr, LValueToRValue, _Bool)
  T: [B4.4] && [B3.2] && ...
  Preds (1): B4
  Succs (2): B2 B0

[B4]
  1: 0
  2: int j = 0;
  3: A
  4: [B4.3] (ImplicitCastExpr, LValueToRValue, _Bool)
  T: [B4.4] && ...
  Preds (1): B5
  Succs (2): B3 B0

[B0 (EXIT)]
  Preds (4): B1 B2 B3 B4

However, even though the path of execution in B2 only depends on C's value,
CFGBlock::getCondition() would return the entire condition (A && B && C). For
B3, it would return A && B. I changed this the actual condition.

Differential Revision: https://reviews.llvm.org/D63538

llvm-svn: 365036
2019-07-03 12:53:19 +00:00
Jennifer Yu b8fee677bf Re-check in clang support gun asm goto after fixing tests.
llvm-svn: 362410
2019-06-03 15:57:25 +00:00