This adds tests for dumping expressions in C. It also updates a comment to note an issue to be fixed with printing character literals discovered as part of this testing.
llvm-svn: 361193
This adds the -ast-dump=json cc1 flag (in addition to -ast-dump=default, which is the default if no dump format is specified), as well as some initial AST dumping functionality and tests.
llvm-svn: 360622
Summary:
currently for:
```
template<typename ... T>
void f(T... t) {
auto l = [t...]{};
}
```
`clang -ast-print file.cpp`
outputs:
```
template <typename ...T> void f(T ...t) {
auto l = [t] {
}
;
}
```
notice that there is not `...` in the capture list of the lambda. this patch fixes this issue. and add test for it.
Patch by Tyker
Reviewers: rsmith
Reviewed By: rsmith
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D61556
llvm-svn: 359980
The FIXME of this test case has been addressed in r335084/r338800. Its
execution still does not succeed because of multiple syntax errors.
First, the "clang" namespace is missing on each of the 4 pragmas.
Second, the pragma for defining the vector width is "vectorize_width(4)"
instead of "vectorize(4)". Third, the pragma for defining the interleave
factor is "interleave_count(8)" instead of "interleave(8)".
The file was already using the wrong syntax when added in
r210925 2014-06-13. The file ast-print-pragmas.cpp already checks for
the correct pragma order, making this test redundant even if fixed.
Differential Revision: https://reviews.llvm.org/D60749
llvm-svn: 358507
Fails on MSVC buildbot (but not locally).
Not important as it is 'testing' something that isn't supported yet anyway:
https://bugs.llvm.org/show_bug.cgi?id=41022
llvm-svn: 356577
Summary:
https://www.openmp.org/wp-content/uploads/OpenMP-API-Specification-5.0.pdf, page 3:
```
structured block
For C/C++, an executable statement, possibly compound, with a single entry at the
top and a single exit at the bottom, or an OpenMP construct.
COMMENT: See Section 2.1 on page 38 for restrictions on structured
blocks.
```
```
2.1 Directive Format
Some executable directives include a structured block. A structured block:
• may contain infinite loops where the point of exit is never reached;
• may halt due to an IEEE exception;
• may contain calls to exit(), _Exit(), quick_exit(), abort() or functions with a
_Noreturn specifier (in C) or a noreturn attribute (in C/C++);
• may be an expression statement, iteration statement, selection statement, or try block, provided
that the corresponding compound statement obtained by enclosing it in { and } would be a
structured block; and
Restrictions
Restrictions to structured blocks are as follows:
• Entry to a structured block must not be the result of a branch.
• The point of exit cannot be a branch out of the structured block.
C / C++
• The point of entry to a structured block must not be a call to setjmp().
• longjmp() and throw() must not violate the entry/exit criteria.
```
Of particular note here is the fact that OpenMP structured blocks are as-if `noexcept`,
in the same sense as with the normal `noexcept` functions in C++.
I.e. if throw happens, and it attempts to travel out of the `noexcept` function
(here: out of the current structured-block), then the program terminates.
Now, one of course can say that since it is explicitly prohibited by the Specification,
then any and all programs that violate this Specification contain undefined behavior,
and are unspecified, and thus no one should care about them. Just don't write broken code /s
But i'm not sure this is a reasonable approach.
I have personally had oss-fuzz issues of this origin - exception thrown inside
of an OpenMP structured-block that is not caught, thus causing program termination.
This issue isn't all that hard to catch, it's not any particularly different from
diagnosing the same situation with the normal `noexcept` function.
Now, clang static analyzer does not presently model exceptions.
But clang-tidy has a simplisic [[ https://clang.llvm.org/extra/clang-tidy/checks/bugprone-exception-escape.html | bugprone-exception-escape ]] check,
and it is even refactored as a `ExceptionAnalyzer` class for reuse.
So it would be trivial to use that analyzer to check for
exceptions escaping out of OpenMP structured blocks. (D59466)
All that sounds too great to be true. Indeed, there is a caveat.
Presently, it's practically impossible to do. To check a OpenMP structured block
you need to somehow 'get' the OpenMP structured block, and you can't because
it's simply not modelled in AST. `CapturedStmt`/`CapturedDecl` is not it's representation.
Now, it is of course possible to write e.g. some AST matcher that would e.g.
match every OpenMP executable directive, and then return the whatever `Stmt` is
the structured block of said executable directive, if any.
But i said //practically//. This isn't practical for the following reasons:
1. This **will** bitrot. That matcher will need to be kept up-to-date,
and refreshed with every new OpenMP spec version.
2. Every single piece of code that would want that knowledge would need to
have such matcher. Well, okay, if it is an AST matcher, it could be shared.
But then you still have `RecursiveASTVisitor` and friends.
`2 > 1`, so now you have code duplication.
So it would be reasonable (and is fully within clang AST spirit) to not
force every single consumer to do that work, but instead store that knowledge
in the correct, and appropriate place - AST, class structure.
Now, there is another hoop we need to get through.
It isn't fully obvious //how// to model this.
The best solution would of course be to simply add a `OMPStructuredBlock` transparent
node. It would be optimal, it would give us two properties:
* Given this `OMPExecutableDirective`, what's it OpenMP structured block?
* It is trivial to check whether the `Stmt*` is a OpenMP structured block (`isa<OMPStructuredBlock>(ptr)`)
But OpenMP structured block isn't **necessarily** the first, direct child of `OMP*Directive`.
(even ignoring the clang's `CapturedStmt`/`CapturedDecl` that were inserted inbetween).
So i'm not sure whether or not we could re-create AST statements after they were already created?
There would be other costs to a new AST node: https://bugs.llvm.org/show_bug.cgi?id=40563#c12
```
1. You will need to break the representation of loops. The body should be replaced by the "structured block" entity.
2. You will need to support serialization/deserialization.
3. You will need to support template instantiation.
4. You will need to support codegen and take this new construct to account in each OpenMP directive.
```
Instead, there **is** an functionally-equivalent, alternative solution, consisting of two parts.
Part 1:
* Add a member function `isStandaloneDirective()` to the `OMPExecutableDirective` class,
that will tell whether this directive is stand-alone or not, as per the spec.
We need it because we can't just check for the existance of associated statements,
see code comment.
* Add a member function `getStructuredBlock()` to the OMPExecutableDirective` class itself,
that assert that this is not a stand-alone directive, and either return the correct loop body
if this is a loop-like directive, or the captured statement.
This way, given an `OMPExecutableDirective`, we can get it's structured block.
Also, since the knowledge is ingrained into the clang OpenMP implementation,
it will not cause any duplication, and //hopefully// won't bitrot.
Great we achieved 1 of 2 properties of `OMPStructuredBlock` approach.
Thus, there is a second part needed:
* How can we check whether a given `Stmt*` is `OMPStructuredBlock`?
Well, we can't really, in general. I can see this workaround:
```
class FunctionASTVisitor : public RecursiveASTVisitor<FunctionASTVisitor> {
using Base = RecursiveASTVisitor<FunctionASTVisitor>;
public:
bool VisitOMPExecDir(OMPExecDir *D) {
OmpStructuredStmts.emplace_back(D.getStructuredStmt());
}
bool VisitSOMETHINGELSE(???) {
if(InOmpStructuredStmt)
HI!
}
bool TraverseStmt(Stmt *Node) {
if (!Node)
return Base::TraverseStmt(Node);
if (OmpStructuredStmts.back() == Node)
++InOmpStructuredStmt;
Base::TraverseStmt(Node);
if (OmpStructuredStmts.back() == Node) {
OmpStructuredStmts.pop_back();
--InOmpStructuredStmt;
}
return true;
}
std::vector<Stmt*> OmpStructuredStmts;
int InOmpStructuredStmt = 0;
};
```
But i really don't see using it in practice.
It's just too intrusive; and again, requires knowledge duplication.
.. but no. The solution lies right on the ground.
Why don't we simply store this `i'm a openmp structured block` in the bitfield of the `Stmt` itself?
This does not appear to have any impact on the memory footprint of the clang AST,
since it's just a single extra bit in the bitfield. At least the static assertions don't fail.
Thus, indeed, we can achieve both of the properties without a new AST node.
We can cheaply set that bit right in sema, at the end of `Sema::ActOnOpenMPExecutableDirective()`,
by just calling the `getStructuredBlock()` that we just added.
Test coverage that demonstrates all this has been added.
This isn't as great with serialization though. Most of it does not use abbrevs,
so we do end up paying the full price (4 bytes?) instead of a single bit.
That price, of course, can be reclaimed by using abbrevs.
In fact, i suspect that //might// not just reclaim these bytes, but pack these PCH significantly.
I'm not seeing a third solution. If there is one, it would be interesting to hear about it.
("just don't write code that would require `isa<OMPStructuredBlock>(ptr)`" is not a solution.)
Fixes [[ https://bugs.llvm.org/show_bug.cgi?id=40563 | PR40563 ]].
Reviewers: ABataev, rjmccall, hfinkel, rsmith, riccibruno, gribozavr
Reviewed By: ABataev, gribozavr
Subscribers: mgorny, aaron.ballman, steveire, guansong, jfb, jdoerfert, cfe-commits
Tags: #clang, #openmp
Differential Revision: https://reviews.llvm.org/D59214
llvm-svn: 356570
Summary:
Split off from D59214.
Not a fully exhaustive test coverage, but better than what there currently is.
Differential Revision: https://reviews.llvm.org/D59306
llvm-svn: 356569
Found by `git grep '\/\/ CHECK-[^: ]* ' clang/test/ | grep -v RUN:`.
Also tweak CodeGenCXX/arm-swiftcall.cpp to still pass now that it checks more.
Differential Revision: https://reviews.llvm.org/D58061
llvm-svn: 353744
This allows substantially simplifying the expression evaluation code,
because we don't have to special-case lvalues which are actually string
literal initialization.
This currently throws away an optimization where we would avoid creating
an array APValue for string literal initialization. If we really want
to optimize this case, we should fix APValue so it can store simple
arrays more efficiently, like llvm::ConstantDataArray. This shouldn't
affect the memory usage for other string literals. (Not sure if this is
a blocker; I don't think string literal init is common enough for this
to be a serious issue, but I could be wrong.)
The change to test/CodeGenObjC/encode-test.m is a weird side-effect of
these changes: we currently don't constant-evaluate arrays in C, so the
strlen call shouldn't be folded, but lvalue string init managed to get
around that check. I this this is fine.
Fixes https://bugs.llvm.org/show_bug.cgi?id=40430 .
llvm-svn: 353569
There is currently no way to distinguish implicit from explicit
CXXThisExpr in the AST dump output.
Differential Revision: https://reviews.llvm.org/D57649
Reviewed By: steveire
llvm-svn: 353003
Further reviews (D57594, D57615) have revealed that this was not reviewed,
and that the differential's description was not read during the review,
thus rendering this commit invalid.
This reverts commit r352882.
llvm-svn: 352933
Summary:
I'm working on a clang-tidy check, much like existing [[ http://clang.llvm.org/extra/clang-tidy/checks/bugprone-exception-escape.html | bugprone-exception-escape ]],
to detect when an exception might escape out of an OpenMP construct it isn't supposed to escape from.
For that i will be using the `nothrow` bit of `CapturedDecl`s.
While that bit is already correctly set for some constructs, e.g. `#pragma omp parallel`: https://godbolt.org/z/2La7pv
it isn't set for the `#pragma omp sections`, or `#pragma omp section`: https://godbolt.org/z/qZ-EbP
If i'm reading [[ https://www.openmp.org/wp-content/uploads/OpenMP-API-Specification-5.0.pdf | `OpenMP Application Programming Interface Version 5.0 November 2018` ]] correctly,
they should be, as per `2.8.1 sections Construct`, starting with page 86:
* The sections construct is a non-iterative worksharing construct that contains a set of **structured blocks**
that are to be distributed among and executed by the threads in a team. Each **structured block** is executed
once by one of the threads in the team in the context of its implicit task.
* The syntax of the sections construct is as follows:
#pragma omp sections [clause[ [,] clause] ... ] new-line
{
[#pragma omp section new-line]
**structured-block**
...
* Description
Each **structured block** in the sections construct is preceded by a section directive except
possibly **the first block**, for which a preceding section directive is optional.
* Restrictions
• The code enclosed in a sections construct must be a **structured block**.
* A throw executed inside a sections region must cause execution to resume within the same
section of the sections region, and the same thread that threw the exception must catch it.
Reviewers: ABataev, #openmp
Reviewed By: ABataev
Subscribers: guansong, openmp-commits, cfe-commits
Tags: #clang, #openmp
Differential Revision: https://reviews.llvm.org/D57585
llvm-svn: 352882
Summary:
Was trying to understand how complicated it would be to write
a clang-tidy `openmp-exception-escape`-ish check once D57100 lands.
Just so it happens, all the data is already there,
it is just conveniently omitted from AST dump.
Reviewers: aaron.ballman, steveire, ABataev
Reviewed By: ABataev
Subscribers: ABataev, guansong, cfe-commits
Tags: #openmp, #clang
Differential Revision: https://reviews.llvm.org/D57452
llvm-svn: 352631
As Discussed here:
http://lists.llvm.org/pipermail/llvm-dev/2019-January/129543.html
There are problems exposing the _Float16 type on architectures that
haven't defined the ABI/ISel for the type yet, so we're temporarily
disabling the type and making it opt-in.
Differential Revision: https://reviews.llvm.org/D57188
Change-Id: I5db7366dedf1deb9485adb8948b1deb7e612a736
llvm-svn: 352221
This is a fix for https://reviews.llvm.org/D51229 where we pass the
address_space qualified type as the modified type of an AttributedType. This
change now instead wraps the AttributedType with either the address_space
qualifier or a DependentAddressSpaceType.
Differential Revision: https://reviews.llvm.org/D55447
llvm-svn: 351997
Summary: Only an obscure case is moved.
Reviewers: aaron.ballman
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D56829
llvm-svn: 351637
Summary:
Removal of the child node makes it easier to separate traversal from
output generation.
Reviewers: aaron.ballman
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D56752
llvm-svn: 351600
Summary:
This makes it easier to separate traversal of the AST from output
generation.
Reviewers: aaron.ballman
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D56751
llvm-svn: 351597
Output all content which is local to the FunctionDecl before traversing
to child AST nodes.
This is necessary so that all of the part which is local to the
FunctionDecl can be split into a different method.
Reviewers: aaron.ballman
Differential Revision: https://reviews.llvm.org/D55083
llvm-svn: 351269
Summary:
Use it to add optional label nodes to Stmt dumps. This preserves
behavior of InitExprList dump:
// CHECK-NEXT: `-InitListExpr {{.+}} <col:13, col:15> 'U [3]'
// CHECK-NEXT: |-array_filler: InitListExpr {{.+}} <col:15> 'U' field Field {{.+}} 'i' 'int'
// CHECK-NEXT: `-InitListExpr {{.+}} <col:14> 'U' field Field {{.+}} 'i' 'int'
// CHECK-NEXT: `-IntegerLiteral {{.+}} <col:14> 'int' 1
Reviewers: aaron.ballman
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D55488
llvm-svn: 350957
Summary:
Currently the Clang AST doesn't store information about how the callee of a CallExpr was found. Specifically if it was found using ADL.
However, this information is invaluable to tooling. Consider a tool which renames usages of a function. If the originally CallExpr was formed using ADL, then the tooling may need to additionally qualify the replacement.
Without information about how the callee was found, the tooling is left scratching it's head. Additionally, we want to be able to match ADL calls as quickly as possible, which means avoiding computing the answer on the fly.
This patch changes `CallExpr` to store whether it's callee was found using ADL. It does not change the size of any AST nodes.
Reviewers: fowles, rsmith, klimek, shafik
Reviewed By: rsmith
Subscribers: aaron.ballman, riccibruno, calabrese, titus, cfe-commits
Differential Revision: https://reviews.llvm.org/D55534
llvm-svn: 348977
Summary: Don't add a child just for the label.
Reviewers: aaron.ballman
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D55495
llvm-svn: 348794
Aaron Ballman