Commit Graph

3229 Commits

Author SHA1 Message Date
Johannes Doerfert 5c1084e884 [OpenMP] Context selector extensions for template functions
With this extension the effects of `omp begin declare variant` will be
applied to template function declarations. The behavior is opt-in and
controlled by the `extension(allow_templates)` trait. While generally
useful, this will enable us to implement complex math function calls by
overloading the templates of the standard library with the ones in
libc++.

Reviewed By: JonChesterfield

Differential Revision: https://reviews.llvm.org/D85735
2020-09-16 13:37:10 -05:00
Elizabeth Andrews 4cff1b40da Do not apply calling conventions to MSVC entry points
Fix link error for MSVC entry points when calling conventions
are specified. MSVC entry points should have default calling
convention.

Differential Revision: https://reviews.llvm.org/D87701
2020-09-16 09:39:37 -07:00
Serge Pavlov f1cd6593da [AST][FPEnv] Keep FP options in trailing storage of CastExpr
This is recommit of 6c8041aa0f, reverted in de044f7562 because of some
fails. Original commit message is below.

This change allow a CastExpr to have optional FPOptionsOverride object,
stored in trailing storage. Of all cast nodes only ImplicitCastExpr,
CStyleCastExpr, CXXFunctionalCastExpr and CXXStaticCastExpr are allowed
to have FPOptions.

Differential Revision: https://reviews.llvm.org/D85960
2020-09-14 12:15:21 +07:00
Serge Pavlov de044f7562 Revert "[AST][FPEnv] Keep FP options in trailing storage of CastExpr"
This reverts commit 6c8041aa0f.
It caused some fails on buildbots.
2020-09-12 17:06:42 +07:00
Serge Pavlov 6c8041aa0f [AST][FPEnv] Keep FP options in trailing storage of CastExpr
This change allow a CastExpr to have optional FPOptionsOverride object,
stored in trailing storage. Of all cast nodes only ImplicitCastExpr,
CStyleCastExpr, CXXFunctionalCastExpr and CXXStaticCastExpr are allowed
to have FPOptions.

Differential Revision: https://reviews.llvm.org/D85960
2020-09-12 14:30:44 +07:00
Aaron Puchert 85fce449dc [Sema] Simplify ShouldDiagnoseUnusedDecl, NFC
Instead of writing to a flag and then returning based on that flag we
can also return directly. The flag name also doesn't provide additional
information, it just reflects the name of the function (isReferenced).
2020-08-29 18:42:58 +02:00
Cullen Rhodes feed5a7239 [Sema][AArch64] Support arm_sve_vector_bits attribute
This patch implements the semantics for the 'arm_sve_vector_bits' type
attribute, defined by the Arm C Language Extensions (ACLE) for SVE [1].
The purpose of this attribute is to define vector-length-specific (VLS)
versions of existing vector-length-agnostic (VLA) types.

The semantics were already implemented by D83551, although the
implementation approach has since changed to represent VLSTs as
VectorType in the AST and fixed-length vectors in the IR everywhere
except in function args/returns. This is described in the prototype
patch D85128 demonstrating the new approach.

The semantic changes added in D83551 are changed since the
AttributedType is replaced by VectorType in the AST. Minimal changes
were necessary in the previous patch as the canonical type for both VLA
and VLS was the same (i.e. sizeless), except in constructs such as
globals and structs where sizeless types are unsupported. This patch
reverts the changes that permitted VLS types that were represented as
sizeless types in such circumstances, and adds support for implicit
casting between VLA <-> VLS types as described in section 3.7.3.2 of the
ACLE.

Since the SVE builtin types for bool and uint8 are both represented as
BuiltinType::UChar in VLSTs, two new vector kinds are implemented to
distinguish predicate and data vectors.

[1] https://developer.arm.com/documentation/100987/latest

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D85736
2020-08-27 10:38:32 +00:00
Jon Chesterfield bcaa806a47 [Clang] Fix BZ47169, loader_uninitialized on incomplete types
[Clang] Fix BZ47169, loader_uninitialized on incomplete types

Reported by @erichkeane. Fix proposed by @erichkeane works, tests included.
Bug introduced in D74361. Crash was on querying a CXXRecordDecl for
hasTrivialDefaultConstructor on an incomplete type. Fixed by calling
RequireCompleteType in the right place.

Reviewed By: erichkeane

Differential Revision: https://reviews.llvm.org/D85990
2020-08-19 18:11:50 +01:00
Dávid Bolvanský 2f7adf5ee3 [Diagnostics] Skip var decl of structs for -Wstring-concatenation 2020-08-13 20:20:26 +02:00
Dávid Bolvanský b9af72bffe [Diagnostics] Reworked -Wstring-concatenation 2020-08-12 02:18:01 +02:00
Erich Keane 0a8ac91a08 Permit nowthrow and nonnull with multiversioning.
Some shipped versions of stdlib.h use nonnull and nothrow with function
multiversioning.  Support these, as they are generally harmless.
2020-08-04 07:40:27 -07:00
Erich Keane 961da69d7e Improve diagnostics for disallowed attributes used with multiversioning
Since we permit using SOME attributes (at the moment, just 1) with
multiversioning, we should improve the message as it still implies that
no attributes should be combined with multiversioning.
2020-08-04 07:40:27 -07:00
Richard Smith a648834313 PR46729: Reject explicit and partial specializations with C linkage. 2020-07-29 17:44:32 -07:00
Richard Smith 1cbdf932b4 PR46231: Promote diagnostic for 'template<...>;' from ExtWarn to Error.
No other compiler accepts this as an extension, not even in permissive
mode. We're not doing anyone any favors by allowing this, and it's
unlikely to be at all common, even in Clang-only code, in the wild.
2020-07-29 12:35:18 -07:00
Bruno Ricci eb10b065f2
[clang] Pass the NamedDecl* instead of the DeclarationName into many diagnostics.
Background:
-----------
There are two related argument types which can be sent into a diagnostic to
display the name of an entity: DeclarationName (ak_declarationname) or
NamedDecl* (ak_nameddecl) (there is also ak_identifierinfo for
IdentifierInfo*, but we are not concerned with it here).

A DeclarationName in a diagnostic will just be streamed to the output,
which will directly result in a call to DeclarationName::print.

A NamedDecl* in a diagnostic will also ultimately result in a call to
DeclarationName::print, but with two customisation points along the way:

The first customisation point is NamedDecl::getNameForDiagnostic which is
overloaded by FunctionDecl, ClassTemplateSpecializationDecl and
VarTemplateSpecializationDecl to print the template arguments, if any.

The second customisation point is NamedDecl::printName. By default it just
streams the stored DeclarationName into the output but it can be customised
to provide a user-friendly name for an entity. It is currently overloaded by
DecompositionDecl and MSGuidDecl.

What this patch does:
---------------------
For many diagnostics a DeclarationName is used instead of the NamedDecl*.
This bypasses the two customisation points mentioned above. This patches fix
this for diagnostics in Sema.cpp, SemaCast.cpp, SemaChecking.cpp, SemaDecl.cpp,
SemaDeclAttr.cpp, SemaDecl.cpp, SemaOverload.cpp and SemaStmt.cpp.

I have only modified diagnostics where I could construct a test-case which
demonstrates that the change is appropriate (either with this patch or the next
one).

Reviewed By: erichkeane, aaron.ballman

Differential Revision: https://reviews.llvm.org/D84656
2020-07-28 10:30:35 +01:00
Richard Smith 23d6525cbd Don't form a 'context-independent expr' reference to a member during
name annotation.

Instead, defer forming the member access expression or DeclRefExpr until
we build the use of ClassifyName's result. Just build an
UnresolvedLookupExpr to track the LookupResult until we're ready to
consume it.

This also reverts commit 2f7269b677 (other
than its testcase). That change was an attempted workaround for the same
problem.
2020-07-27 19:38:22 -07:00
Cullen Rhodes 89e61e782b [Sema][AArch64] Add semantics for arm_sve_vector_bits attribute
Summary:
This patch implements semantics for the 'arm_sve_vector_bits' type
attribute, defined by the Arm C Language Extensions (ACLE) for SVE [1].
The purpose of this attribute is to define fixed-length (VLST) versions
of existing sizeless types (VLAT).

Implemented in this patch is the the behaviour described in section 3.7.3.2
and minimal parts of sections 3.7.3.3 and 3.7.3.4, this includes:

    * Defining VLST globals, structs, unions, and local variables
    * Implicit casting between VLAT <=> VLST.
    * Diagnosis of ill-formed conditional expressions of the form:

        C ?  E1 : E2

      where E1 is a VLAT type and E2 is a VLST, or vice-versa. This
      avoids any ambiguity about the nature of the result type (i.e is
      it sized or sizeless).
    * For vectors:
        * sizeof(VLST) == N/8
        * alignof(VLST) == 16
    * For predicates:
        * sizeof(VLST) == N/64
        * alignof(VLST) == 2

VLSTs have the same representation as VLATs in the AST but are wrapped
with a TypeAttribute. Scalable types are currently emitted in the IR for
uses such as globals and structs which don't support these types, this
is addressed in the next patch with codegen, where VLSTs are lowered to
sized arrays for globals, structs / unions and arrays.

Not implemented in this patch is the behaviour guarded by the feature
macros:

    * __ARM_FEATURE_SVE_VECTOR_OPERATORS
    * __ARM_FEATURE_SVE_PREDICATE_OPERATORS

As such, the GNU __attribute__((vector_size)) extension is not available
and operators such as binary '+' are not supported for VLSTs. Support
for this is intended to be addressed by later patches.

[1] https://developer.arm.com/documentation/100987/latest

This is patch 2/4 of a patch series.

Reviewers: sdesmalen, rsandifo-arm, efriedma, cameron.mcinally, ctetreau, rengolin, aaron.ballman

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D83551
2020-07-22 16:26:23 +00:00
David Blaikie 36036aa70e Reapply "Rename/refactor isIntegerConstantExpression to getIntegerConstantExpression"
Reapply 49e5f603d4
which had been reverted in c94332919b.

Originally reverted because I hadn't updated it in quite a while when I
got around to committing it, so there were a bunch of missing changes to
new code since I'd written the patch.

Reviewers: aaron.ballman

Differential Revision: https://reviews.llvm.org/D76646
2020-07-21 20:57:12 -07:00
Haojian Wu 7af852dcbf [AST][RecoveryExpr] Preserve the invalid "undef_var" initializer.
And don't invalidate the VarDecl if the type is known.

Reviewed By: sammccall

Differential Revision: https://reviews.llvm.org/D81395
2020-07-21 09:38:09 +02:00
Haojian Wu 4b5b7c7541 [AST][RecoveryExpr] Fix a crash on opencl C++.
Differential Revision: https://reviews.llvm.org/D84145
2020-07-20 15:15:30 +02:00
Anastasia Stulova 6050c156ab [OpenCL] Defer addr space deduction for dependent type.
This patch removes deduction of address spaces in parsing
for types that depend on template parameter even if an
address space is already known. Deducing it early interferes
with template instantiation/specialization logic that uses
source address space where address space is not present.

Address space deduction for templates is therefore fully
moved to the template instantiation/specialization phase.

Patch by Ole Strohm (olestrohm)!

Tags: #clang

Differential Revision: https://reviews.llvm.org/D82781
2020-07-13 11:44:38 +01:00
David Blaikie c94332919b Revert "Rename/refactor isIntegerConstantExpression to getIntegerConstantExpression"
Broke buildbots since I hadn't updated this patch in a while. Sorry for
the noise.

This reverts commit 49e5f603d4.
2020-07-12 20:29:19 -07:00
David Blaikie 49e5f603d4 Rename/refactor isIntegerConstantExpression to getIntegerConstantExpression
There is a version that just tests (also called
isIntegerConstantExpression) & whereas this version is specifically used
when the value is of interest (a few call sites were actually refactored
to calling the test-only version) so let's make the API look more like
it.

Reviewers: aaron.ballman

Differential Revision: https://reviews.llvm.org/D76646
2020-07-12 19:43:24 -07:00
Haojian Wu d285f29317 [AST][RecoveryExpr] Avoid spurious 'missing typename' diagnostic when the NNS contains errors.
Differential Revision: https://reviews.llvm.org/D82631
2020-06-30 16:18:32 +02:00
Richard Smith d1446017f3 DR458: Search template parameter scopes in the right order.
C++ unqualified name lookup searches template parameter scopes
immediately after finishing searching the entity the parameters belong
to. (Eg, for a class template, you search the template parameter scope
after looking in that class template and its base classes and before
looking in the scope containing the class template.) This is complicated
by the fact that scope lookup within a template parameter scope looks in
a different sequence of places prior to reaching the end of the
declarator-id in the template declaration.

We used to approximate the proper lookup rule with a hack in the scope /
decl context walk inside name lookup. Now we instead compute the lookup
parent for each template parameter scope.

In order to get this right, we now make sure to enter a distinct Scope
for each template parameter scope, and make sure to re-enter the
enclosing class scopes properly when handling delay-parsed regions
within a class.
2020-06-23 17:14:33 -07:00
Richard Smith 2a3b86c157 Fix rejects-valid when referencing an implicit operator== from within a
templated class.

When a defaulted operator<=> results in the injection of a defaulted
operator==, that operator== can be named by unqualified name within the
same class, even if the class is templated. To make this work, perform
the transform from defaulted operator<=> to defaulted operator== in the
template definition context instead of the template instantiation
context.

This results in our substituting into a declaration from a context where
we don't have a full list of template arguments (or indeed any), for
which we are now more careful to not spuriously instantiate declarations
that are not dependent on the arguments we're substituting.
2020-06-22 20:19:20 -07:00
Haojian Wu 910689f0aa [AST] Move the "fallback to recovery expr" mechanism to CorrectDelayedTyposInExpr, NFC
Summary: Also delete two overloads, which don't seem necessary.

Reviewers: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D82047
2020-06-18 08:20:05 +02:00
Richard Smith 55b6f68f4b Revert "Fix rejects-valid when referencing an implicit operator== from within a"
This change may have caused some self-host failures. Reverting while
investigating.

This reverts commit c7fbe2191b.
2020-06-17 16:05:26 -07:00
Richard Smith c7fbe2191b Fix rejects-valid when referencing an implicit operator== from within a
templated class.

When a defaulted operator<=> results in the injection of a defaulted
operator==, that operator== can be named by unqualified name within the
same class, even if the class is templated. To make this work, perform
the transform from defaulted operator<=> to defaulted operator== in the
template definition context instead of the template instantiation
context.

This results in our substituting into a declaration from a context where
we don't have a full list of template arguments (or indeed any), for
which we are now more careful to not spuriously instantiate declarations
that are not dependent on the arguments we're substituting.
2020-06-17 15:12:04 -07:00
Mariya Podchishchaeva 0bdcd95bf2 [SYCL][OpenMP] Implement thread-local storage restriction
Summary:
SYCL and OpenMP prohibits thread local storage in device code,
so this commit ensures that error is emitted for device code and not
emitted for host code when host target supports it.

Reviewers: jdoerfert, erichkeane, bader

Reviewed By: jdoerfert, erichkeane

Subscribers: guansong, riccibruno, ABataev, yaxunl, ebevhan, Anastasia, sstefan1, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D81641
2020-06-17 14:36:00 +03:00
Richard Smith 02fccc26cf Revert "DR458: Search template parameter scopes in the right order."
We weren't re-entering template scopes in the right order, causing this
to break self-host with -fdelayed-template-parsing.

This reverts commit 237c2a23b6.
2020-06-16 23:53:44 -07:00
Richard Smith 237c2a23b6 DR458: Search template parameter scopes in the right order.
C++ unqualified name lookup searches template parameter scopes
immediately after finishing searching the entity the parameters belong
to. (Eg, for a class template, you search the template parameter scope
after looking in that class template and its base classes and before
looking in the scope containing the class template.) This is complicated
by the fact that scope lookup within a template parameter scope looks in
a different sequence of places prior to reaching the end of the
declarator-id in the template declaration.

We used to approximate the proper lookup rule with a hack in the scope /
decl context walk inside name lookup. Now we instead compute the lookup
parent for each template parameter scope. This gets the right answer and
as a bonus is substantially simpler and more uniform.

In order to get this right, we now make sure to enter a distinct Scope
for each template parameter scope. (The fact that we didn't before was
already a bug, but not really observable most of the time, since
template parameters can't shadow each other.)
2020-06-16 19:41:14 -07:00
Richard Smith 1b8125b041 Don't assert if we find a dependently-typed variable in the
redeclaration chain for an array.

A prior attempt to fix this in r280330 didn't handle the case where the
old variable is dependent and the new one is not.

It is notable and worrying that the test case in this example forms a
redeclaration chain for a non-dependent variable that includes a
declaration with a dependent type. We should probably fix that too.
2020-06-16 19:41:13 -07:00
Haojian Wu 28923dc2dd [AST][RecoveryExpr] Fix a crash on a field decl with invalid type.
Summary:
The field decl (in the testcase) was still valid, which results in a
valid RecordDecl, it led to crash when performing struct layout,
and computing struct size etc.

Reviewers: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D81913
2020-06-16 12:12:10 +02:00
Vy Nguyen a21a462051 Make the diagnostic-missing-prototypes put the suggested `static` in front of `const` if exists.
Summary:
Consider: `const int* get_foo() {return nullptr;}`
The suggested fix should be `static const int* get_foo(){}`
and not `const static int* get_foo(){}`

Reviewers: gribozavr2

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D81444
2020-06-09 19:34:57 -04:00
Richard Smith 56a872947a Remove improper uses of DiagnosticErrorTrap and hasErrorOccurred.
DiagnosticErrorTrap is usually inappropriate because it indicates
whether an error message was rendered in a given region (and is
therefore affected by -ferror-limit and by suppression of errors if we
see an invalid declaration).

hasErrorOccurred() is usually inappropriate because it indicates
whethere an "error:" message was displayed, regardless of whether the
message was a warning promoted to an error, and therefore depends on
things like -Werror that are usually irrelevant.

Where applicable, CodeSynthesisContexts are used to attach notes to
the first diagnostic produced in a region of code, isnstead of using an
error trap and then attaching a note to whichever diagnostic happened to
be produced last (or suppressing the note if the final diagnostic is a
disabled warning!).

This is mostly NFC.
2020-06-08 14:19:57 -07:00
Richard Smith 58f831d2b3 More robust fix for crash on invalid range-based for statement.
Reliably mark the loop variable declaration in a range for as having an
invalid initializer if anything goes wrong building the initializer. We
previously based this determination on whether an error was emitted,
which is not a reliable signal due to error suppression (during error
recovery etc).

Also, properly mark the variable as having initializer errors rather
than simply marking it invalid. This is necessary to mark any structured
bindings as invalid too.

This generalizes the previous fix in
936ec89e91.
2020-06-08 13:11:23 -07:00
Dan Gohman 0d4e243456 [WebAssembly] Improve clang diagnostics for wasm attributes
This patch addresses the review comments on r352930:

 - Removes redundant diagnostic checking code
 - Removes errnoneous use of diag::err_alias_is_definition, which
   turned out to be ineffective anyway since functions can be defined later
   in the translation unit and avoid detection.
 - Adds a test for various invalid cases for import_name and import_module.

This reapplies D59520, with the addition of adding
`InGroup<IgnoredAttributes>` to the new warnings, to fix the
Misc/warning-flags.c failure.

Differential Revision: https://reviews.llvm.org/D59520
2020-06-05 14:32:51 -07:00
Dan Gohman 3aec298349 Revert "[WebAssembly] Improve clang diagnostics for wasm attributes"
It broke clang-check.

This reverts commit 931fcd3ba0.
2020-06-05 11:52:11 -07:00
Dan Gohman 931fcd3ba0 [WebAssembly] Improve clang diagnostics for wasm attributes
This patch addresses the review comments on r352930:

 - Removes redundant diagnostic checking code
 - Removes errnoneous use of diag::err_alias_is_definition, which
   turned out to be ineffective anyway since functions can be defined later
   in the translation unit and avoid detection.
 - Adds a test for various invalid cases for import_name and import_module.

Differential Revision: https://reviews.llvm.org/D59520
2020-06-05 11:27:51 -07:00
Ties Stuij ecd682bbf5 [ARM] Add __bf16 as new Bfloat16 C Type
Summary:
This patch upstreams support for a new storage only bfloat16 C type.
This type is used to implement primitive support for bfloat16 data, in
line with the Bfloat16 extension of the Armv8.6-a architecture, as
detailed here:

https://community.arm.com/developer/ip-products/processors/b/processors-ip-blog/posts/arm-architecture-developments-armv8-6-a

The bfloat type, and its properties are specified in the Arm Architecture
Reference Manual:

https://developer.arm.com/docs/ddi0487/latest/arm-architecture-reference-manual-armv8-for-armv8-a-architecture-profile

In detail this patch:
- introduces an opaque, storage-only C-type __bf16, which introduces a new bfloat IR type.

This is part of a patch series, starting with command-line and Bfloat16
assembly support. The subsequent patches will upstream intrinsics
support for BFloat16, followed by Matrix Multiplication and the
remaining Virtualization features of the armv8.6-a architecture.

The following people contributed to this patch:
- Luke Cheeseman
- Momchil Velikov
- Alexandros Lamprineas
- Luke Geeson
- Simon Tatham
- Ties Stuij

Reviewers: SjoerdMeijer, rjmccall, rsmith, liutianle, RKSimon, craig.topper, jfb, LukeGeeson, fpetrogalli

Reviewed By: SjoerdMeijer

Subscribers: labrinea, majnemer, asmith, dexonsmith, kristof.beyls, arphaman, danielkiss, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D76077
2020-06-05 10:32:43 +01:00
Yaxun (Sam) Liu 049d860707 [CUDA][HIP] Fix constexpr variables for C++17
constexpr variables are compile time constants and implicitly const, therefore
they are safe to emit on both device and host side. Besides, in many cases
they are intended for both device and host, therefore it makes sense
to emit them on both device and host sides if necessary.

In most cases constexpr variables are used as rvalue and the variables
themselves do not need to be emitted. However if their address is taken,
then they need to be emitted.

For C++14, clang is able to handle that since clang emits them with
available_externally linkage together with the initializer.

However for C++17, the constexpr static data member of a class or template class
become inline variables implicitly. Therefore they become definitions with
linkonce_odr or weak_odr linkages. As such, they can not have available_externally
linkage.

This patch fixes that by adding implicit constant attribute to
file scope constexpr variables and constexpr static data members
in device compilation.

Differential Revision: https://reviews.llvm.org/D79237
2020-06-03 21:56:52 -04:00
Mariya Podchishchaeva cf6cc662ee [OpenMP][SYCL] Improve diagnosing of unsupported types usage
Summary:
Diagnostic is emitted if some declaration of unsupported type
declaration is used inside device code.
Memcpy operations for structs containing member with unsupported type
are allowed. Fixed crash on attempt to emit diagnostic outside of the
functions.

The approach is generalized between SYCL and OpenMP.
CUDA/OMP deferred diagnostic interface is going to be used for SYCL device.

Reviewers: rsmith, rjmccall, ABataev, erichkeane, bader, jdoerfert, aaron.ballman

Reviewed By: jdoerfert

Subscribers: guansong, sstefan1, yaxunl, mgorny, bader, ebevhan, Anastasia, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D74387
2020-05-29 18:00:48 +03:00
John Brawn 6c906f7785 [Sema] Diagnose more cases of static data members in local or unnamed classes
We currently diagnose static data members directly contained in unnamed classes,
but we should also diagnose when they're in a class that is nested (directly or
indirectly) in an unnamed class. Do this by iterating up the list of parent
DeclContexts and checking if any is an unnamed class.

Similarly also check for function or method DeclContexts (which includes things
like blocks and openmp captured statements) as then the class is considered to
be a local class, which means static data members aren't allowed.

Differential Revision: https://reviews.llvm.org/D80295
2020-05-26 13:29:59 +01:00
Ronald Wampler 4b53495c4b Perform ActOnConversionDeclarator after looking for any virtual functions it overrides
Summary: This allows for suppressing warnings about the conversion function never being called if it overrides a virtual function in a base class.

Differential Revision: https://reviews.llvm.org/D78444
2020-05-13 10:34:19 -04:00
Haojian Wu 8222107aa9 [AST] Preserve the type in RecoveryExprs for broken function calls.
RecoveryExprs are modeled as dependent type to prevent bogus diagnostics
and crashes in clang.

This patch allows to preseve the type for broken calls when the
RecoveryEprs have a known type, e.g. a broken non-overloaded call, a
overloaded call when the all candidates have the same return type, so
that more features (code completion still work on "take2args(x).^") still
work.

However, adding the type is risky, which may result in more clang code being
affected leading to new crashes and hurt diagnostic, and it requires large
effort to minimize the affect (update all sites in clang to handle errorDepend
case), so we add a new flag (off by default) to allow us to develop/test
them incrementally.

This patch also has some trivial fixes to suppress diagnostics (to prevent regressions).

Tested:

all existing tests are passed (when both "-frecovery-ast", "-frecovery-ast-type" flags are flipped on);

Reviewed By: sammccall

Subscribers: rsmith, arphaman, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D79160
2020-05-11 08:46:18 +02:00
Richard Smith d6425e2c14 Properly implement 'enum class' parsing.
The 'class' or 'struct' keyword is only permitted as part of either an
enum definition or a standalone opaque-enum-declaration, not as part of
an elaborated type specifier. We previously failed to diagnose this, and
generally didn't properly implement the restrictions on elaborated type
specifiers for enumeration types.

In passing, also fixed incorrect parsing for enum-bases, which we
previously parsed as a type-name, but are actually a type-specifier-seq.
This matters for cases like 'enum E : int *p;', which is valid as a
Microsoft extension.

Plus some minor parse diagnostic improvements.

Bumped the recently-added ExtWarn for 'enum E : int x;' to be
DefaultError; this is not an intentional extension, so producing an
error by default seems appropriate, but the warning flag to disable it
may still be useful for code written against old Clang. The same
treatment is given here to the diagnostic for 'enum class E x;', which
we similarly have incorrectly accepted for many years. These diagnostics
continue to be suppressed under -fms-extensions and when compiling
Objective-C code. We will need to decide separately whether Objective-C
should follow the C++ rules or the (older) MSVC rules.
2020-05-10 13:21:04 -07:00
Richard Smith c90e198107 Fix parsing of enum-base to follow C++11 rules.
Previously we implemented non-standard disambiguation rules to
distinguish an enum-base from a bit-field but otherwise treated a :
after an elaborated-enum-specifier as introducing an enum-base. That
misparses various examples (anywhere an elaborated-type-specifier can
appear followed by a colon, such as within a ternary operator or
_Generic).

We now implement the C++11 rules, with the old cases accepted as
extensions where that seemed reasonable. These amount to:
 * an enum-base must always be accompanied by an enum definition (except
   in a standalone declaration of the form 'enum E : T;')
 * in a member-declaration, 'enum E :' always introduces an enum-base,
   never a bit-field
 * in a type-specifier (or similar context), 'enum E :' is not
   permitted; the colon means whatever else it would mean in that
   context.

Fixed underlying types for enums are also permitted in Objective-C and
under MS extensions, plus as a language extension in all other modes.
The behavior in ObjC and MS extensions modes is unchanged (but the
bit-field disambiguation is a bit better); remaining language modes
follow the C++11 rules.

Fixes PR45726, PR39979, PR19810, PR44941, and most of PR24297, plus C++
core issues 1514 and 1966.
2020-05-08 19:32:00 -07:00
Weverything 4ae537c222 Fix false positive with -Wnon-c-typedef-for-linkage
Implicit methods for structs can confuse the warning, so exclude checking
the Decl's that are implicit. Implicit Decl's for lambdas still need to
be checked, so skipping all implicit Decl's won't work.

Differential Revision: https://reviews.llvm.org/D79548
2020-05-07 19:20:08 -07:00
Lucas Prates 9d39df03a9 [Clang][Sema] Capturing section type conflicts between #pragma clang section and section attributes
Summary:
Conflicting types for the same section name defined in clang section
pragmas and GNU-style section attributes were not properly captured by
Clang's Sema. The lack of diagnostics was caused by the fact the section
specification coming from attributes was handled by Sema as implicit,
even though explicitly defined by the user.

This patch enables the diagnostics for section type conflicts between
those specifications by making sure sections defined in section
attributes are correctly handled as explicit.

Reviewers: hans, rnk, javed.absar

Reviewed By: rnk

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D78573
2020-05-07 11:54:46 +01:00
Haojian Wu c6e1fd70fb [clang] Fix a crash on invalid auto.
Summary:
The crash is triggered on accessing a null InitExpr.

For group declaration, e.g. `auto c = a, &d = {a};`, what's happening:

1. each VarDecl is built separately during the parsing stage.
2. perform the semantic analysis (Sema::BuildDeclaratorGroup) to check
whether the type of the two VarDecl is the same, if not mark it as invalid.

in step 1, VarDecl c and d are built, both of them are valid (after D77395),
but d is without the InitExpr attached (under -fno-recovery-ast), crash
happens in step 2 when accessing the source range of d's InitExpr.

Reviewers: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D79473
2020-05-06 11:47:03 +02:00
Haojian Wu 1a0d466081 [AST] Preserve the invalid initializer for auto VarDecl.
Fixes https://github.com/clangd/clangd/issues/330

Reviewers: sammccall

Tags: #clang

Differential Revision: https://reviews.llvm.org/D78365
2020-04-27 10:25:36 +02:00
Aaron Ballman 6a30894391 C++2a -> C++20 in some identifiers; NFC. 2020-04-21 15:37:19 -04:00
Haojian Wu 89d9912cbf [AST] dont invaliate VarDecl when the initializer contains errors.
Summary:
This patch contains 2 separate changes:
1) the initializer of a variable should play no part in decl "invalid" bit;
2) preserve the invalid initializer via recovery exprs;

With 1), we will regress the diagnostics (one big regression is that we loose
the "selected 'begin' function with iterator type" diagnostic in for-range stmt;
but with 2) together, we don't have regressions (the new diagnostics seems to be
improved).

Reviewers: sammccall

Reviewed By: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D78116
2020-04-21 10:53:35 +02:00
Haojian Wu e90fb82f0f [AST] Suppress the spammy "attempt to use a deleted fucntion" diagnostic.
Summary:
This patch fixes the regression diagnostic, which was introduced in
https://reviews.llvm.org/D77395.

Reviewers: sammccall

Reviewed By: sammccall

Subscribers: rsmith, adamcz, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D78100
2020-04-21 09:43:46 +02:00
Erich Keane 5f0903e9be Reland Implement _ExtInt as an extended int type specifier.
I fixed the LLDB issue, so re-applying the patch.

This reverts commit a4b88c0449.
2020-04-17 10:45:48 -07:00
Sterling Augustine a4b88c0449 Revert "Implement _ExtInt as an extended int type specifier."
This reverts commit 61ba1481e2.

I'm reverting this because it breaks the lldb build with
incomplete switch coverage warnings. I would fix it forward,
but am not familiar enough with lldb to determine the correct
fix.

lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp:3958:11: error: enumeration values 'DependentExtInt' and 'ExtInt' not handled in switch [-Werror,-Wswitch]
  switch (qual_type->getTypeClass()) {
          ^
lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp:4633:11: error: enumeration values 'DependentExtInt' and 'ExtInt' not handled in switch [-Werror,-Wswitch]
  switch (qual_type->getTypeClass()) {
          ^
lldb/source/Plugins/TypeSystem/Clang/TypeSystemClang.cpp:4889:11: error: enumeration values 'DependentExtInt' and 'ExtInt' not handled in switch [-Werror,-Wswitch]
  switch (qual_type->getTypeClass()) {
2020-04-17 10:29:40 -07:00
Erich Keane 61ba1481e2 Implement _ExtInt as an extended int type specifier.
Introduction/Motivation:
LLVM-IR supports integers of non-power-of-2 bitwidth, in the iN syntax.
Integers of non-power-of-two aren't particularly interesting or useful
on most hardware, so much so that no language in Clang has been
motivated to expose it before.

However, in the case of FPGA hardware normal integer types where the
full bitwidth isn't used, is extremely wasteful and has severe
performance/space concerns.  Because of this, Intel has introduced this
functionality in the High Level Synthesis compiler[0]
under the name "Arbitrary Precision Integer" (ap_int for short). This
has been extremely useful and effective for our users, permitting them
to optimize their storage and operation space on an architecture where
both can be extremely expensive.

We are proposing upstreaming a more palatable version of this to the
community, in the form of this proposal and accompanying patch.  We are
proposing the syntax _ExtInt(N).  We intend to propose this to the WG14
committee[1], and the underscore-capital seems like the active direction
for a WG14 paper's acceptance.  An alternative that Richard Smith
suggested on the initial review was __int(N), however we believe that
is much less acceptable by WG14.  We considered _Int, however _Int is
used as an identifier in libstdc++ and there is no good way to fall
back to an identifier (since _Int(5) is indistinguishable from an
unnamed initializer of a template type named _Int).

[0]https://www.intel.com/content/www/us/en/software/programmable/quartus-prime/hls-compiler.html)
[1]http://www.open-std.org/jtc1/sc22/wg14/www/docs/n2472.pdf

Differential Revision: https://reviews.llvm.org/D73967
2020-04-17 07:10:57 -07:00
Richard Smith bab6df86ae Rework how UuidAttr, CXXUuidofExpr, and GUID template arguments and constants are represented.
Summary:
Previously, we treated CXXUuidofExpr as quite a special case: it was the
only kind of expression that could be a canonical template argument, it
could be a constant lvalue base object, and so on. In addition, we
represented the UUID value as a string, whose source form we did not
preserve faithfully, and that we partially parsed in multiple different
places.

With this patch, we create an MSGuidDecl object to represent the
implicit object of type 'struct _GUID' created by a UuidAttr. Each
UuidAttr holds a pointer to its 'struct _GUID' and its original
(as-written) UUID string. A non-value-dependent CXXUuidofExpr behaves
like a DeclRefExpr denoting that MSGuidDecl object. We cache an APValue
representation of the GUID on the MSGuidDecl and use it from constant
evaluation where needed.

This allows removing a lot of the special-case logic to handle these
expressions. Unfortunately, many parts of Clang assume there are only
a couple of interesting kinds of ValueDecl, so the total amount of
special-case logic is not really reduced very much.

This fixes a few bugs and issues:
 * PR38490: we now support reading from GUID objects returned from
   __uuidof during constant evaluation.
 * Our Itanium mangling for a non-instantiation-dependent template
   argument involving __uuidof no longer depends on which CXXUuidofExpr
   template argument we happened to see first.
 * We now predeclare ::_GUID, and permit use of __uuidof without
   any header inclusion, better matching MSVC's behavior. We do not
   predefine ::__s_GUID, though; that seems like a step too far.
 * Our IR representation for GUID constants now uses the correct IR type
   wherever possible. We will still fall back to using the
      {i32, i16, i16, [8 x i8]}
   layout if a definition of struct _GUID is not available. This is not
   ideal: in principle the two layouts could have different padding.

Reviewers: rnk, jdoerfert

Subscribers: arphaman, cfe-commits, aeubanks

Tags: #clang

Differential Revision: https://reviews.llvm.org/D78171
2020-04-15 12:20:42 -07:00
Haojian Wu 9657385960 [AST] Dont invalide VarDecl even the default initializaiton is failed.
Summary:
This patch would cause clang emit more diagnostics, but it is much better than https://reviews.llvm.org/D76831

```cpp
struct A {
  A(int);
  ~A() = delete;
};
void k() {
  A a;
}

```

before the patch:

/tmp/t3.cpp:24:5: error: no matching constructor for initialization of 'A'
  A a;
    ^
/tmp/t3.cpp:20:3: note: candidate constructor not viable: requires 1 argument, but 0 were provided
  A(int);
  ^
/tmp/t3.cpp:19:8: note: candidate constructor (the implicit copy constructor) not viable: requires 1 argument, but 0 were provided
struct A {

After the patch:

/tmp/t3.cpp:24:5: error: no matching constructor for initialization of 'A'
  A a;
    ^
/tmp/t3.cpp:20:3: note: candidate constructor not viable: requires 1 argument, but 0 were provided
  A(int);
  ^
/tmp/t3.cpp:19:8: note: candidate constructor (the implicit copy constructor) not viable: requires 1 argument, but 0 were provided
struct A {
       ^
/tmp/t3.cpp:24:5: error: attempt to use a deleted function
  A a;
    ^
/tmp/t3.cpp:21:3: note: '~A' has been explicitly marked deleted here
  ~A() = delete;

Reviewers: sammccall

Reviewed By: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D77395
2020-04-14 12:58:48 +02:00
Yaxun (Sam) Liu 5767085c8d Fix infinite recursion in deferred diag emitter
Currently deferred diagnostic emitter checks variable decl in DeclRefExpr, which
causes infinite recursion for cases like long a = (long)&a;.

Deferred diagnostic emitter does not need check variable decls in DeclRefExpr
since reference of a variable does not cause emission of functions directly or
indirectly. Therefore there is no need to check variable decls in DeclRefExpr.

Differential Revision: https://reviews.llvm.org/D76937
2020-04-01 22:17:43 -04:00
Haojian Wu f757ecbf85 [AST] Fix a crash on invalid bitwidth exprs when preserving the recoveryexprs.
Summary:
If the bitwith expr contains errors, we mark the field decl invalid.

This patch also tweaks the behavior of ObjCInterfaceDecl to be consistent with
existing RecordDecl -- getObjCLayout method is only called with valid decls.

Reviewers: sammccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D76953
2020-03-30 10:52:00 +02:00
Johannes Doerfert befb4be3a8 [OpenMP] `omp begin/end declare variant` - part 2, sema ("+CG")
This is the second part loosely extracted from D71179 and cleaned up.

This patch provides semantic analysis support for `omp begin/end declare
variant`, mostly as defined in OpenMP technical report 8 (TR8) [0].
The sema handling makes code generation obsolete as we generate "the
right" calls that can just be handled as usual. This handling also
applies to the existing, albeit problematic, `omp declare variant
support`. As a consequence a lot of unneeded code generation and
complexity is removed.

A major purpose of this patch is to provide proper `math.h`/`cmath`
support for OpenMP target offloading. See PR42061, PR42798, PR42799. The
current code was developed with this feature in mind, see [1].

The logic is as follows:

If we have seen a `#pragma omp begin declare variant match(<SELECTOR>)`
but not the corresponding `end declare variant`, and we find a function
definition we will:
  1) Create a function declaration for the definition we were about to generate.
  2) Create a function definition but with a mangled name (according to
     `<SELECTOR>`).
  3) Annotate the declaration with the `OMPDeclareVariantAttr`, the same
     one used already for `omp declare variant`, using and the mangled
     function definition as specialization for the context defined by
     `<SELECTOR>`.

When a call is created we inspect it. If the target has an
`OMPDeclareVariantAttr` attribute we try to specialize the call. To this
end, all variants are checked, the best applicable one is picked and a
new call to the specialization is created. The new call is used instead
of the original one to the base function. To keep the AST printing and
tooling possible we utilize the PseudoObjectExpr. The original call is
the syntactic expression, the specialized call is the semantic
expression.

[0] https://www.openmp.org/wp-content/uploads/openmp-TR8.pdf
[1] https://reviews.llvm.org/D61399#change-496lQkg0mhRN

Reviewers: kiranchandramohan, ABataev, RaviNarayanaswamy, gtbercea, grokos, sdmitriev, JonChesterfield, hfinkel, fghanim, aaron.ballman

Subscribers: bollu, guansong, openmp-commits, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D75779
2020-03-27 02:30:58 -05:00
Momchil Velikov 080d046c91 [ARM][CMSE] Implement CMSE attributes
This patch adds CMSE attributes `cmse_nonsecure_call` and
`cmse_nonsecure_entry`.  As usual, specification is available here:
https://developer.arm.com/docs/ecm0359818/latest

Patch by Javed Absar, Bradley Smith, David Green, Momchil Velikov,
possibly others.

Differential Revision: https://reviews.llvm.org/D71129
2020-03-24 10:21:26 +00:00
Haojian Wu 733edf9750 [AST] Add RecoveryExpr to retain expressions on semantic errors
Normally clang avoids creating expressions when it encounters semantic
errors, even if the parser knows which expression to produce.

This works well for the compiler. However, this is not ideal for
source-level tools that have to deal with broken code, e.g. clangd is
not able to provide navigation features even for names that compiler
knows how to resolve.

The new RecoveryExpr aims to capture the minimal set of information
useful for the tools that need to deal with incorrect code:

source range of the expression being dropped,
subexpressions of the expression.
We aim to make constructing RecoveryExprs as simple as possible to
ensure writing code to avoid dropping expressions is easy.

Producing RecoveryExprs can result in new code paths being taken in the
frontend. In particular, clang can produce some new diagnostics now and
we aim to suppress bogus ones based on Expr::containsErrors.

We deliberately produce RecoveryExprs only in the parser for now to
minimize the code affected by this patch. Producing RecoveryExprs in
Sema potentially allows to preserve more information (e.g. type of an
expression), but also results in more code being affected. E.g.
SFINAE checks will have to take presence of RecoveryExprs into account.

Initial implementation only works in C++ mode, as it relies on compiler
postponing diagnostics on dependent expressions. C and ObjC often do not
do this, so they require more work to make sure we do not produce too
many bogus diagnostics on the new expressions.

See documentation of RecoveryExpr for more details.

original patch from Ilya
This change is based on https://reviews.llvm.org/D61722

Reviewers: sammccall, rsmith

Reviewed By: sammccall, rsmith

Tags: #clang

Differential Revision: https://reviews.llvm.org/D69330
2020-03-24 09:20:37 +01:00
Yaxun (Sam) Liu b670ab7b6b recommit 1b978ddba0 [CUDA][HIP][OpenMP] Emit deferred diagnostics by a post-parsing AST travese
Differential Revision: https://reviews.llvm.org/D70172
2020-03-23 12:09:07 -04:00
Akira Hatanaka d35a454170 [CodeGen] Emit destructor calls to destruct non-trivial C struct objects
returned by function calls or loaded from volatile objects

rdar://problem/51867864

Differential Revision: https://reviews.llvm.org/D66094
2020-03-20 18:34:22 -07:00
Jon Chesterfield c45eaeabb7 [Clang] Undef attribute for global variables
Summary:
[Clang] Attribute to allow defining undef global variables

Initializing global variables is very cheap on hosted implementations. The
C semantics of zero initializing globals work very well there. It is not
necessarily cheap on freestanding implementations. Where there is no loader
available, code must be emitted near the start point to write the appropriate
values into memory.

At present, external variables can be declared in C++ and definitions provided
in assembly (or IR) to achive this effect. This patch provides an attribute in
order to remove this reason for writing assembly for performance sensitive
freestanding implementations.

A close analogue in tree is LDS memory for amdgcn, where the kernel is
responsible for initializing the memory after it starts executing on the gpu.
Uninitalized variables in LDS are observably cheaper than zero initialized.

Patch is loosely based on the cuda __shared__ and opencl __local variable
implementation which also produces undef global variables.

Reviewers: kcc, rjmccall, rsmith, glider, vitalybuka, pcc, eugenis, vlad.tsyrklevich, jdoerfert, gregrodgers, jfb, aaron.ballman

Reviewed By: rjmccall, aaron.ballman

Subscribers: Anastasia, aaron.ballman, davidb, Quuxplusone, dexonsmith, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D74361
2020-03-17 21:22:23 +00:00
Richard Sandiford 994c071a1b [Sema][SVE] Reject arrays of sizeless types
The SVE ACLE doesn't allow arrays of sizeless types.  At the moment
clang accepts the TU:

  __SVInt8_t x[2];

but trying to code-generate it triggers the LLVM assertion:

  llvm/lib/IR/Type.cpp:588: static llvm::ArrayType* llvm::ArrayType::get(llvm::Type*, uint64_t): Assertion `isValidElementType(ElementType) && "Invalid type for array element!"' failed.

This patch reports an appropriate error instead.

The rules are slightly more restrictive than for general incomplete types.
For example:

  struct s;
  typedef struct s arr[2];

is valid as far as it goes, whereas arrays of sizeless types are
invalid in all contexts.  BuildArrayType therefore needs a specific
check for isSizelessType in addition to the usual handling of
incomplete types.

Differential Revision: https://reviews.llvm.org/D76082
2020-03-13 19:28:45 +00:00
Richard Sandiford b50d80c1ee [Sema][SVE] Don't allow fields to have sizeless type
The SVE ACLE doesn't allow fields to have sizeless type.  At the moment
clang accepts things like:

  struct s { __SVInt8_t x; } y;

but trying to code-generate it leads to LLVM asserts like:

  llvm/include/llvm/Support/TypeSize.h:126: uint64_t llvm::TypeSize::getFixedSize() const: Assertion `!IsScalable && "Request for a fixed size on a scalable object"' failed.

This patch adds an associated clang diagnostic.

Differential Revision: https://reviews.llvm.org/D75737
2020-03-13 19:22:23 +00:00
Richard Smith 9975dc38bf Defer checking for mismatches between the deletedness of and overriding
function and an overridden function until we know whether the overriding
function is deleted.

We previously did these checks when we first built the declaration,
which was too soon in some cases. We now defer all these checks to the
end of the class.

Also add missing check that a consteval function cannot override a
non-consteval function and vice versa.
2020-03-12 13:07:22 -07:00
Richard Sandiford f8700db7f1 [Sema][SVE] Don't allow static or thread-local variables to have sizeless type
clang accepts a TU containing just:

  __SVInt8_t x;

However, sizeless types are not allowed to have static or thread-local
storage duration and trying to code-generate the TU triggers an LLVM
fatal error:

  Globals cannot contain scalable vectors
  <vscale x 16 x i8>* @x
  fatal error: error in backend: Broken module found, compilation aborted!

This patch adds an associated clang diagnostic.

Differential Revision: https://reviews.llvm.org/D75736
2020-03-12 17:39:29 +00:00
Erich Keane cc8390bfe3 Permit attribute 'used' with 'target' multiversioning.
This adds infrastructure for a multiversioning whitelist, plus adds
'used' to the allowed list with 'target'.  The behavior here mirrors the
implementation in GCC, where 'used' only applies to the single
declaration and doesn't apply to the ifunc or resolver.

This is not being applied to cpu_dispatch and cpu_specific, since the
rules are more complicated for cpu_specific, which emits multiple
symbols. Additionally, the author isn't currently aware of uses in the
wild of this combination, but is aware of a number of target+used
combinations.
2020-03-09 12:38:03 -07:00
Akira Hatanaka e4dfc9f5bd Fix the type of the capture passed to LambdaIntroducer::addCapture in
RebuildLambdaScopeInfo

Previously the type of the variable was being passed, which was causing
clang to crash when a non-reference variable was captured by reference
or a reference variable was captured by value by a lambda and a block
nested inside the lambda body was referencing the variable.

Original patch by JF Bastien.

rdar://problem/47550338

Differential Revision: https://reviews.llvm.org/D58164
2020-03-09 12:25:28 -07:00
Reid Kleckner 04da3dfecc Forward declare special case lists
This avoids pulling in unordered_map from TrigramIndex.h:

$ diff -u thedeps-before.txt thedeps-after.txt | \
        grep '^[-+] ' | sort | uniq -c | sort -nr
    976 -    ../llvm/include/llvm/Support/TrigramIndex.h
    976 -    ../llvm/include/llvm/Support/SpecialCaseList.h
    976 -    ../clang/include/clang/Basic/SanitizerSpecialCaseList.h
    502 -    ../../../PROGRA~2/MIB055~1/2019/PROFES~1/VC/Tools/MSVC/14.24.28314/include/unordered_map
    467 -    ../../../PROGRA~2/MIB055~1/2019/PROFES~1/VC/Tools/MSVC/14.24.28314/include/xhash
    467 -    ../../../PROGRA~2/MIB055~1/2019/PROFES~1/VC/Tools/MSVC/14.24.28314/include/xbit_ops.h
    212 -    ../llvm/include/llvm/ADT/StringSet.h
2020-02-27 10:05:30 -08:00
Roman Lebedev 3dd5a298bf
[clang] Annotating C++'s `operator new` with more attributes
Summary:
Right now we annotate C++'s `operator new` with `noalias` attribute,
which very much is healthy for optimizations.

However as per [[ http://eel.is/c++draft/basic.stc.dynamic.allocation | `[basic.stc.dynamic.allocation]` ]],
there are more promises on global `operator new`, namely:
* non-`std::nothrow_t` `operator new` *never* returns `nullptr`
* If `std::align_val_t align` parameter is taken, the pointer will also be `align`-aligned
* ~~global `operator new`-returned pointer is `__STDCPP_DEFAULT_NEW_ALIGNMENT__`-aligned ~~ It's more caveated than that.

Supplying this information may not cause immediate landslide effects
on any specific benchmarks, but it for sure will be healthy for optimizer
in the sense that the IR will better reflect the guarantees provided in the source code.

The caveat is `-fno-assume-sane-operator-new`, which currently prevents emitting `noalias`
attribute, and is automatically passed by Sanitizers ([[ https://bugs.llvm.org/show_bug.cgi?id=16386 | PR16386 ]]) - should it also cover these attributes?
The problem is that the flag is back-end-specific, as seen in `test/Modules/explicit-build-flags.cpp`.
But while it is okay to add `noalias` metadata in backend, we really should be adding at least
the alignment metadata to the AST, since that allows us to perform sema checks on it.

Reviewers: erichkeane, rjmccall, jdoerfert, eugenis, rsmith

Reviewed By: rsmith

Subscribers: xbolva00, jrtc27, atanasyan, nlopes, cfe-commits

Tags: #llvm, #clang

Differential Revision: https://reviews.llvm.org/D73380
2020-02-26 01:37:17 +03:00
Yaxun (Sam) Liu bcadb1f2e6 Revert "[CUDA][HIP][OpenMP] Emit deferred diagnostics by a post-parsing AST travese"
This reverts commit 1b978ddba0.
2020-02-18 14:45:34 -05:00
Yaxun (Sam) Liu 1b978ddba0 [CUDA][HIP][OpenMP] Emit deferred diagnostics by a post-parsing AST travese
This patch removes the explicit call graph for CUDA/HIP/OpenMP deferred
diagnostics generated during parsing since it is error prone due to
incomplete information about function declarations during parsing. In stead,
this patch does a post-parsing AST traverse and emits deferred diagnostics
based on the use graph implicitly generated during the traverse.

Differential Revision: https://reviews.llvm.org/D70172
2020-02-16 22:44:33 -05:00
Aaron Puchert 2f26bc5542 Warn about zero-parameter K&R definitions in -Wstrict-prototypes
Summary:
Zero-parameter K&R definitions specify that the function has no
parameters, but they are still not prototypes, so calling the function
with the wrong number of parameters is just a warning, not an error.

The C11 standard doesn't seem to directly define what a prototype is,
but it can be inferred from 6.9.1p7: "If the declarator includes a
parameter type list, the list also specifies the types of all the
parameters; such a declarator also serves as a function prototype
for later calls to the same function in the same translation unit."
This refers to 6.7.6.3p5: "If, in the declaration “T D1”, D1 has
the form
    D(parameter-type-list)
or
    D(identifier-list_opt)
[...]". Later in 6.11.7 it also refers only to the parameter-type-list
variant as prototype: "The use of function definitions with separate
parameter identifier and declaration lists (not prototype-format
parameter type and identifier declarators) is an obsolescent feature."

We already correctly treat an empty parameter list as non-prototype
declaration, so we can just take that information.

GCC also warns about this with -Wstrict-prototypes.

This shouldn't affect C++, because there all FunctionType's are
FunctionProtoTypes. I added a simple test for that.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D66919
2020-02-14 19:25:02 +01:00
Richard Smith 7ae1b4a0ce Implement P1766R1: diagnose giving non-C-compatible classes a typedef name for linkage purposes.
Summary:
Due to a recent (but retroactive) C++ rule change, only sufficiently
C-compatible classes are permitted to be given a typedef name for
linkage purposes. Add an enabled-by-default warning for these cases, and
rephrase our existing error for the case where we encounter the typedef
name for linkage after we've already computed and used a wrong linkage
in terms of the new rule.

Reviewers: rjmccall

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D74103
2020-02-07 11:47:37 -08:00
Tyker 008e7bf923 [C++20] Add consteval-specific semantic for functions
Summary:
Changes:
 - Calls to consteval function are now evaluated in constant context but IR is still generated for them.
 - Add diagnostic for taking address of a consteval function in non-constexpr context.
 - Add diagnostic for address of consteval function accessible at runtime.
 - Add tests

Reviewers: rsmith, aaron.ballman

Reviewed By: rsmith

Subscribers: mgrang, riccibruno, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D63960
2020-02-04 20:38:32 +01:00
Aaron Puchert 27684ae66d Don't warn about missing declarations for partial template specializations
Summary: Just like templates, they are excepted from the ODR rule.

Reviewed By: aaron.ballman, rsmith

Differential Revision: https://reviews.llvm.org/D68923
2020-02-01 00:06:03 +01:00
Benjamin Kramer adcd026838 Make llvm::StringRef to std::string conversions explicit.
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.
2020-01-28 23:25:25 +01:00
Reid Kleckner 0ebc8e6c42 [Sema] Remove unneeded TreeTransform.h includes, NFC
SemaDecl.cpp and SemaType.cpp don't have any TreeTransforms.
2020-01-24 17:48:38 -08:00
Saar Raz b481f02814 [Concepts] Placeholder constraints and abbreviated templates
This patch implements P1141R2 "Yet another approach for constrained declarations".

General strategy for this patch was:

- Expand AutoType to include optional type-constraint, reflecting the wording and easing the integration of constraints.
- Replace autos in parameter type specifiers with invented parameters in GetTypeSpecTypeForDeclarator, using the same logic
  previously used for generic lambdas, now unified with abbreviated templates, by:
  - Tracking the template parameter lists in the Declarator object
  - Tracking the template parameter depth before parsing function declarators (at which point we can match template
    parameters against scope specifiers to know if we have an explicit template parameter list to append invented parameters
    to or not).
- When encountering an AutoType in a parameter context we check a stack of InventedTemplateParameterInfo structures that
  contain the info required to create and accumulate invented template parameters (fields that were already present in
  LambdaScopeInfo, which now inherits from this class and is looked up when an auto is encountered in a lambda context).

Resubmit after fixing MSAN failures caused by incomplete initialization of AutoTypeLocs in TypeSpecLocFiller.

Differential Revision: https://reviews.llvm.org/D65042
2020-01-23 19:39:43 +02:00
Sam McCall 5c02fe1faa Revert "[Concepts] Placeholder constraints and abbreviated templates"
This reverts commit e57a9abc4b.

Parser/cxx2a-placeholder-type-constraint.cpp has MSan failures.

Present at 7b81c3f8793d30a4285095a9b67dcfca2117916c:
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-bootstrap-msan/builds/17133/steps/check-clang%20msan/logs/stdio
not present at eaa594f4ec54eba52b03fd9f1c789b214c66a753:
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-bootstrap-msan/builds/17132/steps/check-clang%20msan/logs/stdio

Stack trace:
```
==57032==WARNING: MemorySanitizer: use-of-uninitialized-value
    #0 0xccfe016 in clang::AutoTypeLoc::getLocalSourceRange() const /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/include/clang/AST/TypeLoc.h:2036:19
    #1 0xcc56758 in CheckDeducedPlaceholderConstraints(clang::Sema&, clang::AutoType const&, clang::AutoTypeLoc, clang::QualType) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Sema/SemaTemplateDeduction.cpp:4505:56
    #2 0xcc550ce in clang::Sema::DeduceAutoType(clang::TypeLoc, clang::Expr*&, clang::QualType&, llvm::Optional<unsigned int>, bool) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Sema/SemaTemplateDeduction.cpp:4707:11
    #3 0xcc52407 in clang::Sema::DeduceAutoType(clang::TypeSourceInfo*, clang::Expr*&, clang::QualType&, llvm::Optional<unsigned int>, bool) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Sema/SemaTemplateDeduction.cpp:4457:10
    #4 0xba38332 in clang::Sema::deduceVarTypeFromInitializer(clang::VarDecl*, clang::DeclarationName, clang::QualType, clang::TypeSourceInfo*, clang::SourceRange, bool, clang::Expr*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Sema/SemaDecl.cpp:11351:7
    #5 0xba3a8a9 in clang::Sema::DeduceVariableDeclarationType(clang::VarDecl*, bool, clang::Expr*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Sema/SemaDecl.cpp:11385:26
    #6 0xba3c520 in clang::Sema::AddInitializerToDecl(clang::Decl*, clang::Expr*, bool) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Sema/SemaDecl.cpp:11725:9
    #7 0xb39c498 in clang::Parser::ParseDeclarationAfterDeclaratorAndAttributes(clang::Declarator&, clang::Parser::ParsedTemplateInfo const&, clang::Parser::ForRangeInit*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/ParseDecl.cpp:2399:17
    #8 0xb394d80 in clang::Parser::ParseDeclGroup(clang::ParsingDeclSpec&, clang::DeclaratorContext, clang::SourceLocation*, clang::Parser::ForRangeInit*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/ParseDecl.cpp:2128:21
    #9 0xb383bbf in clang::Parser::ParseSimpleDeclaration(clang::DeclaratorContext, clang::SourceLocation&, clang::Parser::ParsedAttributesWithRange&, bool, clang::Parser::ForRangeInit*, clang::SourceLocation*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/ParseDecl.cpp:1848:10
    #10 0xb383129 in clang::Parser::ParseDeclaration(clang::DeclaratorContext, clang::SourceLocation&, clang::Parser::ParsedAttributesWithRange&, clang::SourceLocation*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/llvm/include/llvm/ADT/PointerUnion.h
    #11 0xb53a388 in clang::Parser::ParseStatementOrDeclarationAfterAttributes(llvm::SmallVector<clang::Stmt*, 32u>&, clang::Parser::ParsedStmtContext, clang::SourceLocation*, clang::Parser::ParsedAttributesWithRange&) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/ParseStmt.cpp:221:13
    #12 0xb539309 in clang::Parser::ParseStatementOrDeclaration(llvm::SmallVector<clang::Stmt*, 32u>&, clang::Parser::ParsedStmtContext, clang::SourceLocation*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/ParseStmt.cpp:106:20
    #13 0xb55610e in clang::Parser::ParseCompoundStatementBody(bool) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/ParseStmt.cpp:1079:11
    #14 0xb559529 in clang::Parser::ParseFunctionStatementBody(clang::Decl*, clang::Parser::ParseScope&) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/ParseStmt.cpp:2204:21
    #15 0xb33c13e in clang::Parser::ParseFunctionDefinition(clang::ParsingDeclarator&, clang::Parser::ParsedTemplateInfo const&, clang::Parser::LateParsedAttrList*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/Parser.cpp:1339:10
    #16 0xb394703 in clang::Parser::ParseDeclGroup(clang::ParsingDeclSpec&, clang::DeclaratorContext, clang::SourceLocation*, clang::Parser::ForRangeInit*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/ParseDecl.cpp:2068:11
    #17 0xb338e52 in clang::Parser::ParseDeclOrFunctionDefInternal(clang::Parser::ParsedAttributesWithRange&, clang::ParsingDeclSpec&, clang::AccessSpecifier) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/Parser.cpp:1099:10
    #18 0xb337674 in clang::Parser::ParseDeclarationOrFunctionDefinition(clang::Parser::ParsedAttributesWithRange&, clang::ParsingDeclSpec*, clang::AccessSpecifier) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/Parser.cpp:1115:12
    #19 0xb334a96 in clang::Parser::ParseExternalDeclaration(clang::Parser::ParsedAttributesWithRange&, clang::ParsingDeclSpec*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/Parser.cpp:935:12
    #20 0xb32f12a in clang::Parser::ParseTopLevelDecl(clang::OpaquePtr<clang::DeclGroupRef>&, bool) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/Parser.cpp:686:12
    #21 0xb31e193 in clang::ParseAST(clang::Sema&, bool, bool) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Parse/ParseAST.cpp:158:20
    #22 0x80263f0 in clang::FrontendAction::Execute() /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Frontend/FrontendAction.cpp:936:8
    #23 0x7f2a257 in clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/Frontend/CompilerInstance.cpp:965:33
    #24 0x8288bef in clang::ExecuteCompilerInvocation(clang::CompilerInstance*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/lib/FrontendTool/ExecuteCompilerInvocation.cpp:290:25
    #25 0xad44c2 in cc1_main(llvm::ArrayRef<char const*>, char const*, void*) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/tools/driver/cc1_main.cpp:239:15
    #26 0xacd76a in ExecuteCC1Tool(llvm::ArrayRef<char const*>) /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/tools/driver/driver.cpp:325:12
    #27 0xacc9fd in main /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/clang/tools/driver/driver.cpp:398:12
    #28 0x7f7d82cdb2e0 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x202e0)
    #29 0xa4dde9 in _start (/b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm_build_msan/bin/clang-11+0xa4dde9)
```
2020-01-23 10:38:59 +01:00
Saar Raz e57a9abc4b [Concepts] Placeholder constraints and abbreviated templates
This patch implements P1141R2 "Yet another approach for constrained declarations".

General strategy for this patch was:

- Expand AutoType to include optional type-constraint, reflecting the wording and easing the integration of constraints.
- Replace autos in parameter type specifiers with invented parameters in GetTypeSpecTypeForDeclarator, using the same logic
  previously used for generic lambdas, now unified with abbreviated templates, by:
  - Tracking the template parameter lists in the Declarator object
  - Tracking the template parameter depth before parsing function declarators (at which point we can match template
    parameters against scope specifiers to know if we have an explicit template parameter list to append invented parameters
    to or not).
- When encountering an AutoType in a parameter context we check a stack of InventedTemplateParameterInfo structures that
  contain the info required to create and accumulate invented template parameters (fields that were already present in
  LambdaScopeInfo, which now inherits from this class and is looked up when an auto is encountered in a lambda context).

Resubmit after incorrect check in NonTypeTemplateParmDecl broke lldb.

Differential Revision: https://reviews.llvm.org/D65042
2020-01-22 12:09:13 +02:00
Jonas Devlieghere 62e4b501ab Revert "[Concepts] Placeholder constraints and abbreviated templates"
This temporarily reverts commit e03ead6771
because it breaks LLDB.

http://lab.llvm.org:8011/builders/lldb-x86_64-debian/builds/3356
http://lab.llvm.org:8011/builders/lldb-x64-windows-ninja/builds/12872
http://green.lab.llvm.org/green/view/LLDB/job/lldb-cmake/6407/
2020-01-21 19:03:52 -08:00
Saar Raz e03ead6771 [Concepts] Placeholder constraints and abbreviated templates
This patch implements P1141R2 "Yet another approach for constrained declarations".

General strategy for this patch was:

- Expand AutoType to include optional type-constraint, reflecting the wording and easing the integration of constraints.
- Replace autos in parameter type specifiers with invented parameters in GetTypeSpecTypeForDeclarator, using the same logic
  previously used for generic lambdas, now unified with abbreviated templates, by:
  - Tracking the template parameter lists in the Declarator object
  - Tracking the template parameter depth before parsing function declarators (at which point we can match template
    parameters against scope specifiers to know if we have an explicit template parameter list to append invented parameters
    to or not).
- When encountering an AutoType in a parameter context we check a stack of InventedTemplateParameterInfo structures that
  contain the info required to create and accumulate invented template parameters (fields that were already present in
  LambdaScopeInfo, which now inherits from this class and is looked up when an auto is encountered in a lambda context).

Differential Revision: https://reviews.llvm.org/D65042
2020-01-22 02:03:05 +02:00
Saar Raz a0f50d7316 [Concepts] Requires Expressions
Implement support for C++2a requires-expressions.

Re-commit after compilation failure on some platforms due to alignment issues with PointerIntPair.

Differential Revision: https://reviews.llvm.org/D50360
2020-01-19 00:23:26 +02:00
Saar Raz baa84d8cde Revert "[Concepts] Requires Expressions"
This reverts commit 0279318997.

There have been some failing tests on some platforms, reverting while investigating.
2020-01-18 14:58:01 +02:00
Saar Raz 0279318997 [Concepts] Requires Expressions
Implement support for C++2a requires-expressions.

Differential Revision: https://reviews.llvm.org/D50360
2020-01-18 09:15:36 +02:00
Simon Pilgrim ded237b58d Fix "pointer is null" static analyzer warning. NFCI.
Use castAs<> instead of getAs<> since the pointer is dereferenced immediately below and castAs will perform the null assertion for us.
2020-01-11 16:02:22 +00:00
Saar Raz b65b1f322b [Concepts] Function trailing requires clauses
Function trailing requires clauses now parsed, supported in overload resolution and when calling, referencing and taking the address of functions or function templates.

Differential Revision: https://reviews.llvm.org/D43357
2020-01-09 15:07:51 +02:00
Zachary Henkel 0acfc49317 Allow redeclaration of __declspec(uuid)
msvc allows a subsequent declaration of a uuid attribute on a
struct/class.  Mirror this behavior in clang-cl.

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D71439
2019-12-28 13:13:46 -08:00
Anastasia Stulova 869d17d851 [OpenCL] Pretty print __private addr space
Add printing of __private address space to TypePrinter to allow
it appears in diagnostics and AST dumps as all other language
addr spaces.

Tags: #clang

Differential Revision: https://reviews.llvm.org/D71272
2019-12-27 13:42:07 +00:00
Yonghong Song e3d8ee35e4 reland "[DebugInfo] Support to emit debugInfo for extern variables"
Commit d77ae1552f
("[DebugInfo] Support to emit debugInfo for extern variables")
added deebugInfo for extern variables for BPF target.
The commit is reverted by 891e25b02d
as the committed tests using %clang instead of %clang_cc1 causing
test failed in certain scenarios as reported by Reid Kleckner.

This patch fixed the tests by using %clang_cc1.

Differential Revision: https://reviews.llvm.org/D71818
2019-12-22 18:28:50 -08:00
Reid Kleckner 891e25b02d Revert "[DebugInfo] Support to emit debugInfo for extern variables"
This reverts commit d77ae1552f.

The tests committed along with this change do not pass, and should be
changed to use %clang_cc1.
2019-12-22 12:54:06 -08:00
Kamlesh Kumar 304d1304b7 Apply the alignment specifier attribute to anonymous unions and structs. 2019-12-20 14:42:37 -05:00
Amy Huang a85f5efd95 Add support for the MS qualifiers __ptr32, __ptr64, __sptr, __uptr.
Summary:
This adds parsing of the qualifiers __ptr32, __ptr64, __sptr, and __uptr and
lowers them to the corresponding address space pointer for 32-bit and 64-bit pointers.
(32/64-bit pointers added in https://reviews.llvm.org/D69639)

A large part of this patch is making these pointers ignore the address space
when doing things like overloading and casting.

https://bugs.llvm.org/show_bug.cgi?id=42359

Reviewers: rnk, rsmith

Subscribers: jholewinski, jvesely, nhaehnle, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D71039
2019-12-18 10:41:12 -08:00