This is a major change on how we represent nested name qualifications in
the AST.
* The nested name specifier itself and how it's stored is changed. The
prefixes for types are handled within the type hierarchy, which makes
canonicalization for them super cheap, no memory allocation required.
Also translating a type into nested name specifier form becomes a no-op.
An identifier is stored as a DependentNameType. The nested name
specifier gains a lightweight handle class, to be used instead of
passing around pointers, which is similar to what is implemented for
TemplateName. There is still one free bit available, and this handle can
be used within a PointerUnion and PointerIntPair, which should keep
bit-packing aficionados happy.
* The ElaboratedType node is removed, all type nodes in which it could
previously apply to can now store the elaborated keyword and name
qualifier, tail allocating when present.
* TagTypes can now point to the exact declaration found when producing
these, as opposed to the previous situation of there only existing one
TagType per entity. This increases the amount of type sugar retained,
and can have several applications, for example in tracking module
ownership, and other tools which care about source file origins, such as
IWYU. These TagTypes are lazily allocated, in order to limit the
increase in AST size.
This patch offers a great performance benefit.
It greatly improves compilation time for
[stdexec](https://github.com/NVIDIA/stdexec). For one datapoint, for
`test_on2.cpp` in that project, which is the slowest compiling test,
this patch improves `-c` compilation time by about 7.2%, with the
`-fsyntax-only` improvement being at ~12%.
This has great results on compile-time-tracker as well:
This patch also further enables other optimziations in the future, and
will reduce the performance impact of template specialization resugaring
when that lands.
It has some other miscelaneous drive-by fixes.
About the review: Yes the patch is huge, sorry about that. Part of the
reason is that I started by the nested name specifier part, before the
ElaboratedType part, but that had a huge performance downside, as
ElaboratedType is a big performance hog. I didn't have the steam to go
back and change the patch after the fact.
There is also a lot of internal API changes, and it made sense to remove
ElaboratedType in one go, versus removing it from one type at a time, as
that would present much more churn to the users. Also, the nested name
specifier having a different API avoids missing changes related to how
prefixes work now, which could make existing code compile but not work.
How to review: The important changes are all in
`clang/include/clang/AST` and `clang/lib/AST`, with also important
changes in `clang/lib/Sema/TreeTransform.h`.
The rest and bulk of the changes are mostly consequences of the changes
in API.
PS: TagType::getDecl is renamed to `getOriginalDecl` in this patch, just
for easier to rebasing. I plan to rename it back after this lands.
Fixes#136624
Fixes https://github.com/llvm/llvm-project/issues/43179
Fixes https://github.com/llvm/llvm-project/issues/68670
Fixes https://github.com/llvm/llvm-project/issues/92757
This changes the type compatibility rules so that it is permitted to
redefine tag types within the same TU so long as they are equivalent
definitions.
It is intentionally not being exposed as an extension in older C
language modes. GCC does not do so and the feature doesn't seem
compelling enough to warrant it.
Structural equivalence check uses a cache to store already found
non-equivalent values. This cache can be reused for calls (ASTImporter
does this). Value of "IgnoreTemplateParmDepth" can have an effect on the
structural equivalence therefore it is wrong to reuse the same cache for
checks with different values of 'IgnoreTemplateParmDepth'. The current
change adds the 'IgnoreTemplateParmDepth' to the cache key to fix the
problem.
These tests are for multiple anonymous EnumDecls structural eq test &
importing.
We found the anonymous enums importing issue a few days ago and tried to
fix it
but 0a6233a68c7b575d05bca0f0c708b7e97cc710d1 already did this. I think
these tests are still useful for regressions.
improve `ASTStructuralEquivalenceTest`:
1. compare the depth and index of NTTP
2. provide comparison of `CXXDependentScopeMemberExpr` to `StmtCompare`.
Co-authored-by: huqizhi <836744285@qq.com>
Operators that are overloadable may be parsed as `CXXOperatorCallExpr`
or as `UnaryOperator` (or `BinaryOperator`). This depends on the context
and can be different if a similar construct is imported into an existing
AST. The two "forms" of the operator call AST nodes should be detected
as equivalent to allow AST import of these cases.
This fix has probably other consequences because if a structure is
imported that has `CXXOperatorCallExpr` into an AST with an existing
similar structure that has `UnaryOperator` (or binary), the additional
data in the `CXXOperatorCallExpr` node is lost at the import (because
the existing node will be used). I am not sure if this can cause
problems.
Types comparison in `StructuralEquivalence` ignores its `DeclContext`
when they are generated by template specialization implicitly and this
will produce incorrect result. Add comparison of `DeclContext` of
ClassTemplateSpecializationDecl to improve result.
fix [issue](https://github.com/llvm/llvm-project/issues/65913)
Co-authored-by: huqizhi <836744285@qq.com>
improve AST comparasion on VarDecl & GotoStmt:
1. VarDecl should not be ignored,
2. GotoStmt has no children, it should be handle explicitly.
Reviewed By: donat.nagy
Differential Revision: https://reviews.llvm.org/D159519
Co-authored-by: huqizhi <836744285@qq.com>
In the comparation of return statement, return value(if it is
CXXBoolLiteralExpr) should be handled explicitly, otherwise an
incorrect result would be returned.
Reviewed By: steakhal, donat.nagy
Differential Revision: https://reviews.llvm.org/D159479
Depth of the parameter of friend template class declaration in a
template class is 1, while in the specialization the depth is 0.
This will cause failure on 'IsStructurallyEquivalent' as a name
conflict in 'VisitClassTemplateDecl'(see testcase of
'SkipComparingFriendTemplateDepth'). The patch fix it by ignore
the depth only in this special case.
Reviewed By: balazske
Differential Revision: https://reviews.llvm.org/D156693
When this happens, it is invalid code and there is diagnostic
```
error: cannot find interface declaration for '...'
```
But clang shouldn't crash even if code is invalid. Though subsequent
diagnostic can be imperfect because without ObjCInterfaceDecl we don't have
a type for error messages.
rdar://108818430
Differential Revision: https://reviews.llvm.org/D151523
The forwarding header is left in place because of its use in
`polly/lib/External/isl/interface/extract_interface.cc`, but I have
added a GCC warning about the fact it is deprecated, because it is used
in `isl` from where it is included by Polly.
Basically NFC: A TEST/TEST_F/etc that bails out early (usually because
setup failed or some other runtime condition wasn't met) generally
should use GTEST_SKIP() to report its status correctly, unless it
takes steps to report another status (e.g., FAIL()).
I went over the output of the following mess of a command:
(ulimit -m 2000000; ulimit -v 2000000; git ls-files -z |
parallel --xargs -0 cat | aspell list --mode=none --ignore-case |
grep -E '^[A-Za-z][a-z]*$' | sort | uniq -c | sort -n |
grep -vE '.{25}' | aspell pipe -W3 | grep : | cut -d' ' -f2 | less)
and proceeded to spend a few days looking at it to find probable typos
and fixed a few hundred of them in all of the llvm project (note, the
ones I found are not anywhere near all of them, but it seems like a
good start).
Differential Revision: https://reviews.llvm.org/D130827
The AST structural equivalence check did not differentiate between
a struct and a struct with same name in different namespace. When
type of a member is checked it is possible to encounter such a case
and wrongly decide that the types are similar. This problem is fixed
by check for the namespaces of a record declaration.
Reviewed By: martong
Differential Revision: https://reviews.llvm.org/D113118
The AST structural equivalence check did not differentiate between
a struct and a struct with same name in different namespace. When
type of a member is checked it is possible to encounter such a case
and wrongly decide that the types are similar. This problem is fixed
by check for the namespaces of a record declaration.
Reviewed By: martong
Differential Revision: https://reviews.llvm.org/D113118
1. Moves the check to ASTStructuralEquivalence.cpp like all the other checks.
2. Adds the missing checks for identifier and init expression. Also add the
respective tests for that stuff.
Reviewed By: martong
Differential Revision: https://reviews.llvm.org/D112804
This allows ASTs to be merged when they contain GenericSelectionExpr
nodes (this is _Generic from C11). This is needed, for example, for
CTU analysis of C code that makes use of _Generic, like the Linux
kernel.
The node is already supported in the AST, but it didn't have a matcher
in ASTMatchers. So, this change adds the matcher and adds support to
ASTImporter. Additionally, this change adds support for structural
equivalence of _Generic in the AST.
Reviewed By: martong, aaron.ballman
Differential Revision: https://reviews.llvm.org/D92600
There are several `::IsStructurallyEquivalent` overloads for Decl subclasses
that are used for comparing declarations. There is also one overload that takes
just two Decl pointers which ends up queuing the passed Decls to be later
compared in `CheckKindSpecificEquivalence`.
`CheckKindSpecificEquivalence` implements the dispatch logic for the different
Decl subclasses. It is supposed to hand over the queued Decls to the
subclass-specific `::IsStructurallyEquivalent` overload that will actually
compare the Decl instance. It also seems to implement a few pieces of actual
node comparison logic inbetween the dispatch code.
This implementation causes that the different overloads of
`::IsStructurallyEquivalent` do different (and sometimes no) comparisons
depending on which overload of `::IsStructurallyEquivalent` ends up being
called.
For example, if I want to compare two FieldDecl instances, then I could either
call the `::IsStructurallyEquivalent` with `Decl *` or with `FieldDecl *`
parameters. The overload that takes FieldDecls is doing a correct comparison.
However, the `Decl *` overload just queues the Decl pair.
`CheckKindSpecificEquivalence` has no dispatch logic for `FieldDecl`, so it
always returns true and never does any actual comparison.
On the other hand, if I try to compare two FunctionDecl instances the two
possible overloads of `::IsStructurallyEquivalent` have the opposite behaviour:
The overload that takes `FunctionDecl` pointers isn't comparing the names of the
FunctionDecls while the overload taking a plain `Decl` ends up comparing the
function names (as the comparison logic for that is implemented in
`CheckKindSpecificEquivalence`).
This patch tries to make this set of functions more consistent by making
`CheckKindSpecificEquivalence` a pure dispatch function without any
subclass-specific comparison logic. Also the dispatch logic is now autogenerated
so it can no longer miss certain subclasses.
The comparison code from `CheckKindSpecificEquivalence` is moved to the
respective `::IsStructurallyEquivalent` overload so that the comparison result
no longer depends if one calls the `Decl *` overload or the overload for the
specific subclass. The only difference is now that the `Decl *` overload is
queuing the parameter while the subclass-specific overload is directly doing the
comparison.
`::IsStructurallyEquivalent` is an implementation detail and I don't think the
behaviour causes any bugs in the current implementation (as carefully calling
the right overload for the different classes works around the issue), so the
test for this change is that I added some new code for comparing `MemberExpr`.
The new comparison code always calls the dispatching overload and it previously
failed as the dispatch didn't support FieldDecls.
Reviewed By: martong, a_sidorin
Differential Revision: https://reviews.llvm.org/D87619
Right now the ASTImporter assumes for most Expr nodes that they are always equal
which leads to non-compatible declarations ending up being merged. This patch
adds the basic framework for comparing Stmts (and with that also Exprs) and
implements the custom checks for a few Stmt subclasses. I'll implement the
remaining subclasses in follow up patches (mostly because there are a lot of
subclasses and some of them require further changes like having GNU language in
the testing framework)
The motivation for this is that in LLDB we try to import libc++ source code and
some of the types we are importing there contain expressions (e.g. because they
use `enable_if<expr>`), so those declarations are currently merged even if they
are completely different (e.g. `enable_if<value> ...` and `enable_if<!value>
...` are currently considered equal which is clearly not true).
Reviewed By: martong, balazske
Differential Revision: https://reviews.llvm.org/D87444
Summary:
Import declarations in correct order if a class contains
multiple redundant friend (type or decl) declarations.
If the order is incorrect this could cause false structural
equivalences and wrong declaration chains after import.
Reviewers: a.sidorin, shafik, a_sidorin
Reviewed By: shafik
Subscribers: dkrupp, Szelethus, gamesh411, teemperor, martong, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D75740
Summary:
I think we would be better off with tests explicitly specifying the
language mode. Right now Lang_C means C99, but reads as "any C version",
or as "unspecified C version".
I also changed '-std=c++98' to '-std=c++03' because they are aliases (so
there is no difference in practice), because Clang implements C++03
rules in practice, and because 03 makes a nice sortable progression
between 03, 11, 14, 17, 20.
Reviewers: shafik, hlopko
Reviewed By: hlopko
Subscribers: jfb, martong, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D81000
Summary:
unittests/AST/Language.h defines some helpers that we would like to
reuse in other tests, for example, in tests for syntax trees.
Reviewers: sammccall
Reviewed By: sammccall
Subscribers: mgorny, martong, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D80792
Summary:
Declaring these helpers in the ast_matcher namespace in the clangAST
unit test seems inappropriate -- neither these helpers, nor clangAST have
anything to do with AST matchers. Therefore, I moved these helpers to
the clang namespace.
Declaring another typedef called "ArgVector" is not a good idea -- we
already have both "ArgVector", "ArgsVector", and "ArgList". I expanded
it into the underlying type.
Declaring another enum called "Language" is not a good idea because we
arleady have the "clang::Language" enum. I renamed it to
"TestLanguage".
Similarly, I renamed "getBasicRunOptionsForLanguage" to
"getCommandLineArgsForTesting" to explain the semantics better (what are
"run options"?) and not repeat types in the function name
("ForLanguage").
Reviewers: shafik, rengolin, sammccall
Reviewed By: sammccall
Subscribers: gribozavr2, sammccall, martong, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D80786
Summary:
The structural equivalence check stores now pairs of nodes in the
'from' and 'to' context instead of only the node in 'from' context
and a corresponding one in 'to' context. This is needed to handle
cases when a Decl in the 'from' context is to be compared with
multiple Decls in the 'to' context.
Reviewers: martong, a_sidorin
Reviewed By: martong, a_sidorin
Subscribers: rnkovacs, dkrupp, Szelethus, gamesh411, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D66538
llvm-svn: 370639
Summary:
We falsely state inequivalence if the template parameter is a
qualified/nonquialified template in the first/second instantiation.
Also, different kinds of TemplateName should be equal if the template
decl (if available) is equal (even if the name kind is different).
Reviewers: a_sidorin, a.sidorin
Subscribers: rnkovacs, dkrupp, Szelethus, gamesh411, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D64241
llvm-svn: 366818
Summary:
The structural equivalence check reported false eq between lambda classes
with different parameters in their call signature.
The solution is to check the methods for equality too in case of lambda
classes.
Reviewers: a_sidorin, a.sidorin
Subscribers: rnkovacs, dkrupp, Szelethus, gamesh411, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D64075
llvm-svn: 366332
This caused Clang to start erroring on the following:
struct S {
template <typename = int> explicit S();
};
struct T : S {};
struct U : T {
U();
};
U::U() {}
$ clang -c /tmp/x.cc
/tmp/x.cc:10:4: error: call to implicitly-deleted default constructor of 'T'
U::U() {}
^
/tmp/x.cc:5:12: note: default constructor of 'T' is implicitly deleted
because base class 'S' has no default constructor
struct T : S {};
^
1 error generated.
See discussion on the cfe-commits email thread.
This also reverts the follow-ups r359966 and r359968.
> this patch adds support for the explicit bool specifier.
>
> Changes:
> - The parsing for the explicit(bool) specifier was added in ParseDecl.cpp.
> - The storage of the explicit specifier was changed. the explicit specifier was stored as a boolean value in the FunctionDeclBitfields and in the DeclSpec class. now it is stored as a PointerIntPair<Expr*, 2> with a flag and a potential expression in CXXConstructorDecl, CXXDeductionGuideDecl, CXXConversionDecl and in the DeclSpec class.
> - Following the AST change, Serialization, ASTMatchers, ASTComparator and ASTPrinter were adapted.
> - Template instantiation was adapted to instantiate the potential expressions of the explicit(bool) specifier When instantiating their associated declaration.
> - The Add*Candidate functions were adapted, they now take a Boolean indicating if the context allowing explicit constructor or conversion function and this boolean is used to remove invalid overloads that required template instantiation to be detected.
> - Test for Semantic and Serialization were added.
>
> This patch is not yet complete. I still need to check that interaction with CTAD and deduction guides is correct. and add more tests for AST operations. But I wanted first feedback.
> Perhaps this patch should be spited in smaller patches, but making each patch testable as a standalone may be tricky.
>
> Patch by Tyker
>
> Differential Revision: https://reviews.llvm.org/D60934
llvm-svn: 360024
this patch adds support for the explicit bool specifier.
Changes:
- The parsing for the explicit(bool) specifier was added in ParseDecl.cpp.
- The storage of the explicit specifier was changed. the explicit specifier was stored as a boolean value in the FunctionDeclBitfields and in the DeclSpec class. now it is stored as a PointerIntPair<Expr*, 2> with a flag and a potential expression in CXXConstructorDecl, CXXDeductionGuideDecl, CXXConversionDecl and in the DeclSpec class.
- Following the AST change, Serialization, ASTMatchers, ASTComparator and ASTPrinter were adapted.
- Template instantiation was adapted to instantiate the potential expressions of the explicit(bool) specifier When instantiating their associated declaration.
- The Add*Candidate functions were adapted, they now take a Boolean indicating if the context allowing explicit constructor or conversion function and this boolean is used to remove invalid overloads that required template instantiation to be detected.
- Test for Semantic and Serialization were added.
This patch is not yet complete. I still need to check that interaction with CTAD and deduction guides is correct. and add more tests for AST operations. But I wanted first feedback.
Perhaps this patch should be spited in smaller patches, but making each patch testable as a standalone may be tricky.
Patch by Tyker
Differential Revision: https://reviews.llvm.org/D60934
llvm-svn: 359949
Summary: Operators kind was not checked, so we reported e.g. op- to be equal with op+
Reviewers: shafik, a_sidorin, aaron.ballman
Subscribers: rnkovacs, dkrupp, Szelethus, gamesh411, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D57902
llvm-svn: 353504
Summary:
New tests added to verify equivalency of templates when their
parameters are different.
Reviewers: a_sidorin, shafik
Subscribers: rnkovacs, dkrupp, Szelethus, gamesh411, cfe-commits
Differential Revision: https://reviews.llvm.org/D57235
llvm-svn: 352345
Fix remaining unittest errors caused by
__attribute__((no_caller_saved_registers))
Related commit which caused the buildbots to fail:
rL352050
llvm-svn: 352060
Summary:
FunctionType::ExtInfo holds such properties of a function which are needed
mostly for code gen. We should not compare these bits when checking for
structural equivalency.
Checking ExtInfo caused false ODR errors during CTU analysis (of tmux).
Reviewers: a_sidorin, a.sidorin, shafik
Subscribers: rnkovacs, dkrupp, Szelethus, cfe-commits
Differential Revision: https://reviews.llvm.org/D53699
llvm-svn: 352050
Summary:
The crux of the issue that is being fixed is that lookup could not find
previous decls of a friend class. The solution involves making the
friend declarations visible in their decl context (i.e. adding them to
the lookup table).
Also, we simplify `VisitRecordDecl` greatly.
This fix involves two other repairs (without these the unittests fail):
(1) We could not handle the addition of injected class types properly
when a redecl chain was involved, now this is fixed.
(2) DeclContext::removeDecl failed if the lookup table in Vector form
did not contain the to be removed element. This caused troubles in
ASTImporter::ImportDeclContext. This is also fixed.
Reviewers: a_sidorin, balazske, a.sidorin
Subscribers: rnkovacs, dkrupp, Szelethus, cfe-commits
Differential Revision: https://reviews.llvm.org/D53655
llvm-svn: 349349
Summary:
Currently we consider one forward declared RecordDecl and another with a
definition equal. We have to do the same in case of enums.
Reviewers: a_sidorin, r.stahl, xazax.hun
Subscribers: rnkovacs, dkrupp, cfe-commits
Differential Revision: https://reviews.llvm.org/D50444
llvm-svn: 339336
Summary:
When checking a class or function the described class or function template
is checked too.
Split StructuralEquivalenceContext::Finish into multiple functions.
Improved test with symmetric check, added new tests.
Reviewers: martong, a.sidorin, a_sidorin, bruno
Reviewed By: martong, a.sidorin
Subscribers: rnkovacs, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D49223
llvm-svn: 339256
Summary:
Implementation functions call into the member functions of
ASTStructuralEquivalence, thus they can falsely alter the DeclsToCheck state
(they add decls). This results that some leaf declarations can be stated as
inequivalent as a side effect of one inequivalent element in the DeclsToCheck
list. And since we store the non-equivalencies, any (otherwise independent)
decls will be rendered as non-equivalent. Solution: I tried to clearly
separate the implementation functions (the static ones) and the public
interface. From now on, the implementation functions do not call any public
member functions, only other implementation functions.
Reviewers: a.sidorin, a_sidorin, r.stahl
Subscribers: rnkovacs, dkrupp, cfe-commits
Differential Revision: https://reviews.llvm.org/D49300
llvm-svn: 337275
Summary:
D48773 simplified ASTImporter nicely, but it introduced a new error: Unnamed
structs are not imported correctly, if they appear in a recursive context.
This patch provides a fix for structural equivalency.
Reviewers: a.sidorin, a_sidorin, balazske, gerazo
Subscribers: rnkovacs, dkrupp, cfe-commits
Differential Revision: https://reviews.llvm.org/D49296
llvm-svn: 337267
