500 Commits

Author SHA1 Message Date
Chuanqi Xu
7a541406b5 Revert "[C++20] [Modules] Implement Reachable initiallly"
This reverts commit a223ba0a697c1598b434cf2495c9cd9ec5640fc7.

The previous commit don't contain additional information, which is bad.
2022-06-29 12:43:26 +08:00
Chuanqi Xu
a223ba0a69 [C++20] [Modules] Implement Reachable initiallly 2022-06-29 12:32:31 +08:00
Erich Keane
017abbb258 Revert ""Re-apply 4b6c2cd642 "Deferred Concept Instantiation Implementation"""""
This reverts commit a425cac31e2e4cee8e14b7b9a99c8ba17c1ebb52.

There is another libc++ test, that this time causes us to hit an
assertion. Reverting, likely for a while this time.
2022-05-09 09:12:05 -07:00
Erich Keane
a425cac31e "Re-apply 4b6c2cd642 "Deferred Concept Instantiation Implementation""""
This includes a fix for the libc++ issue I ran across with friend
declarations not properly being identified as overloads.

This reverts commit 45c07db31cc76802a1a2e41bed1ce9c1b8198181.
2022-05-09 06:29:47 -07:00
Erich Keane
45c07db31c Revert "Re-apply 4b6c2cd642 "Deferred Concept Instantiation Implementation"""
This reverts commit a97899108e495147985e5e9492e742d51d5cc97a.

The patch caused some problems with the libc++ `__range_adaptor_closure`
that I haven't been able to figure out the cause of, so I am reverting
while I figure out whether this is a solvable problem/issue with the
  CFE, or libc++ depending on an older 'incorrect' behavior.
2022-05-02 11:12:14 -07:00
Erich Keane
a97899108e Re-apply 4b6c2cd642 "Deferred Concept Instantiation Implementation""
This reverts commit 0c31da48389754822dc3eecc4723160c295b9ab2.

I've solved the issue with the PointerUnion by making the
`FunctionTemplateDecl` pointer be a NamedDecl, that could be a
`FunctionDecl` or `FunctionTemplateDecl` depending.  This is enforced
with an assert.
2022-05-02 07:49:26 -07:00
Erich Keane
0c31da4838 Revert "Deferred Concept Instantiation Implementation"
This reverts commit 4b6c2cd647e9e5a147954886338f97ffb6a1bcfb.

The patch caused numerous ARM 32 bit build failures, since we added a
5th item to the PointerUnion, and went over the 2-bits available in the
32 bit pointers.
2022-05-02 06:25:38 -07:00
Erich Keane
4b6c2cd647 Deferred Concept Instantiation Implementation
As reported here: https://github.com/llvm/llvm-project/issues/44178

Concepts are not supposed to be instantiated until they are checked, so
this patch implements that and goes through significant amounts of work
to make sure we properly re-instantiate the concepts correctly.

Differential Revision: https://reviews.llvm.org/D119544
2022-05-02 05:49:15 -07:00
Sam McCall
0cd5cd19af [Serialization] write expr dependence bits as a single integer
When exprs are written unabbreviated:
  - these were encoded as 5 x vbr6 = 30 bits
  - now they fit exactly into a one-chunk vbr = 6 bits

clangd --check=clangd/AST.cpp reports ~1% reduction in PCH size
(42826720->42474460)

Differential Revision: https://reviews.llvm.org/D124250
2022-04-25 12:09:40 +02:00
Chuanqi Xu
3cec39b91c [C++20] [Modules] Don't generate strong function of a partition in importing modules
This solves the multiple defintiion issue
https://github.com/llvm/llvm-project/issues/54269.

I think the cause of the bug might be an oversight. We just forget to
edit this when implementing partitions. And it should be a good fix.

Reviewed By: iains

Differential Revision: https://reviews.llvm.org/D121271
2022-04-01 14:36:04 +08:00
James Y Knight
d614874900 [Clang] Implement __builtin_source_location.
This builtin returns the address of a global instance of the
`std::source_location::__impl` type, which must be defined (with an
appropriate shape) before calling the builtin.

It will be used to implement std::source_location in libc++ in a
future change. The builtin is compatible with GCC's implementation,
and libstdc++'s usage. An intentional divergence is that GCC declares
the builtin's return type to be `const void*` (for
ease-of-implementation reasons), while Clang uses the actual type,
`const std::source_location::__impl*`.

In order to support this new functionality, I've also added a new
'UnnamedGlobalConstantDecl'. This artificial Decl is modeled after
MSGuidDecl, and is used to represent a generic concept of an lvalue
constant with global scope, deduplicated by its value. It's possible
that MSGuidDecl itself, or some of the other similar sorts of things
in Clang might be able to be refactored onto this more-generic
concept, but there's enough special-case weirdness in MSGuidDecl that
I gave up attempting to share code there, at least for now.

Finally, for compatibility with libstdc++'s <source_location> header,
I've added a second exception to the "cannot cast from void* to T* in
constant evaluation" rule. This seems a bit distasteful, but feels
like the best available option.

Reviewers: aaron.ballman, erichkeane

Differential Revision: https://reviews.llvm.org/D120159
2022-03-28 18:29:02 -04:00
Benjamin Kramer
5d2ce7663b Use llvm::append_range instead of push_back loops where applicable. NFCI. 2022-03-18 01:25:34 +01:00
Nathan Ridge
7a8c7946fc [clang] Allocate 2 bits to store the constexpr specifier kind when serializing
Now that consteval and constinit are possible values, 1 bit
is no longer enough.

Fixes https://github.com/clangd/clangd/issues/887

Differential Revision: https://reviews.llvm.org/D111971
2021-11-17 16:56:46 -05:00
Nathan Sidwell
b2d0c16e91 [clang] p1099 using enum part 2
This implements the 'using enum maybe-qualified-enum-tag ;' part of
1099. It introduces a new 'UsingEnumDecl', subclassed from
'BaseUsingDecl'. Much of the diff is the boilerplate needed to get the
new class set up.

There is one case where we accept ill-formed, but I believe this is
merely an extended case of an existing bug, so consider it
orthogonal. AFAICT in class-scope the c++20 rule is that no 2 using
decls can bring in the same target decl ([namespace.udecl]/8). But we
already accept:

struct A { enum { a }; };
struct B : A { using A::a; };
struct C : B { using A::a;
using B::a; }; // same enumerator

this patch permits mixtures of 'using enum Bob;' and 'using Bob::member;' in the same way.

Differential Revision: https://reviews.llvm.org/D102241
2021-06-08 11:11:46 -07:00
Erik Pilkington
369c648399 [clang] Implement the using_if_exists attribute
This attribute applies to a using declaration, and permits importing a
declaration without knowing if that declaration exists. This is useful
for libc++ C wrapper headers that re-export declarations in std::, in
cases where the base C library doesn't provide all declarations.

This attribute was proposed in http://lists.llvm.org/pipermail/cfe-dev/2020-June/066038.html.

rdar://69313357

Differential Revision: https://reviews.llvm.org/D90188
2021-06-02 10:30:24 -04:00
Richard Smith
d38057f3ec Treat implicit deduction guides as being equivalent to their
corresponding constructor for access checking purposes.
2021-05-19 13:31:53 -07:00
Nathan Sidwell
ab7316f1c6 [clang] Spell correct variable
fix Trailling -> Trailing (two ll-> one l)

Differential Revision: https://reviews.llvm.org/D101753
2021-05-03 05:33:47 -07:00
Vassil Vassilev
0cb7e7ca0c Make iteration over the DeclContext::lookup_result safe.
The idiom:
```
DeclContext::lookup_result R = DeclContext::lookup(Name);
for (auto *D : R) {...}
```

is not safe when in the loop body we trigger deserialization from an AST file.
The deserialization can insert new declarations in the StoredDeclsList whose
underlying type is a vector. When the vector decides to reallocate its storage
the pointer we hold becomes invalid.

This patch replaces a SmallVector with an singly-linked list. The current
approach stores a SmallVector<NamedDecl*, 4> which is around 8 pointers.
The linked list is 3, 5, or 7. We do better in terms of memory usage for small
cases (and worse in terms of locality -- the linked list entries won't be near
each other, but will be near their corresponding declarations, and we were going
to fetch those memory pages anyway). For larger cases: the vector uses a
doubling strategy for reallocation, so will generally be between half-full and
full. Let's say it's 75% full on average, so there's N * 4/3 + 4 pointers' worth
of space allocated currently and will be 2N pointers with the linked list. So we
break even when there are N=6 entries and slightly lose in terms of memory usage
after that. We suspect that's still a win on average.

Thanks to @rsmith!

Differential revision: https://reviews.llvm.org/D91524
2021-03-17 08:59:04 +00:00
Thorsten Schütt
2fd11e0b1e Revert "[NFC, Refactor] Modernize StorageClass from Specifiers.h to a scoped enum (II)"
This reverts commit efc82c4ad2bcb256a4f4c20238d08cd3afba4d2d.
2021-01-04 23:17:45 +01:00
Thorsten Schütt
efc82c4ad2 [NFC, Refactor] Modernize StorageClass from Specifiers.h to a scoped enum (II)
Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D93765
2021-01-04 22:58:26 +01:00
Thorsten
41b65f166b Convert ConstexprKind from Specifiers.h to a scoped enum; NFC 2020-11-16 14:10:19 -05:00
Zequan Wu
e56e7bd469 Revert "Revert "Ensure that checkInitIsICE is called exactly once for every variable""
This reverts commit a2ac64dd905422ed84e273a98d846df022a5e2ec.
2020-10-26 12:08:57 -07:00
Zequan Wu
a2ac64dd90 Revert "Ensure that checkInitIsICE is called exactly once for every variable"
This causing `Assertion Result && "Could not evaluate expression"' failed` at https://bugs.chromium.org/p/chromium/issues/detail?id=1142009

This reverts commit 76c0092665867a6defcd328ba0d0d976eb65d991.
2020-10-26 11:59:55 -07:00
Melanie Blower
2e204e2391 [clang] Enable support for #pragma STDC FENV_ACCESS
Reviewers: rjmccall, rsmith, sepavloff

Differential Revision: https://reviews.llvm.org/D87528
2020-10-25 06:46:25 -07:00
Richard Smith
ba4768c966 [c++20] For P0732R2 / P1907R1: Basic frontend support for class types as
non-type template parameters.

Create a unique TemplateParamObjectDecl instance for each such value,
representing the globally unique template parameter object to which the
template parameter refers.

No IR generation support yet; that will follow in a separate patch.
2020-10-21 13:21:41 -07:00
Richard Smith
3692d20d2b Refactor tracking of constant initializers for variables.
Instead of framing the interface around whether the variable is an ICE
(which is only interesting in C++98), primarily track whether the
initializer is a constant initializer (which is interesting in all C++
language modes).

No functionality change intended.
2020-10-19 21:31:19 -07:00
Richard Smith
76c0092665 Ensure that checkInitIsICE is called exactly once for every variable
for which it matters.

This is a step towards separating checking for a constant initializer
(in which std::is_constant_evaluated returns true) and any other
evaluation of a variable initializer (in which it returns false).
2020-10-19 19:04:04 -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 6c8041aa0ffed827636935e59c489b1e390c8542.
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
Alexey Bataev
0af7835eae [OPENMP]Redesign of OMPExecutableDirective/OMPDeclarativeDirective representation.
Summary:
Introduced OMPChildren class to handle all associated clauses, statement
and child expressions/statements. It allows to represent some directives
more correctly (like flush, depobj etc. with pseudo clauses, ordered
depend directives, which are standalone, and target data directives).
Also, it will make easier to avoid using of CapturedStmt in directives,
if required (atomic, tile etc. directives).
Also, it simplifies serialization/deserialization of the
executable/declarative directives.
Reduces number of allocation operations for mapper declarations.

Reviewers: jdoerfert

Subscribers: yaxunl, guansong, jfb, cfe-commits, sstefan1, aaron.ballman, caomhin

Tags: #clang

Differential Revision: https://reviews.llvm.org/D83261
2020-08-06 12:25:19 -04:00
David Blaikie
b198de67e0 Merge some of the PCH object support with modular codegen
I was trying to pick this up a bit when reviewing D48426 (& perhaps D69778) - in any case, looks like D48426 added a module level flag that might not be needed.

The D48426 implementation worked by setting a module level flag, then code generating contents from the PCH a special case in ASTContext::DeclMustBeEmitted would be used to delay emitting the definition of these functions if they came from a Module with this flag.

This strategy is similar to the one initially implemented for modular codegen that was removed in D29901 in favor of the modular decls list and a bit on each decl to specify whether it's homed to a module.

One major difference between PCH object support and modular code generation, other than the specific list of decls that are homed, is the compilation model: MSVC PCH modules are built into the object file for some other source file (when compiling that source file /Yc is specified to say "this compilation is where the PCH is homed"), whereas modular code generation invokes a separate compilation for the PCH alone. So the current modular code generation test of to decide if a decl should be emitted "is the module where this decl is serialized the current main file" has to be extended (as Lubos did in D69778) to also test the command line flag -building-pch-with-obj.

Otherwise the whole thing is basically streamlined down to the modular code generation path.

This even offers one extra material improvement compared to the existing divergent implementation: Homed functions are not emitted into object files that use the pch. Instead at -O0 they are not emitted into the IR at all, and at -O1 they are emitted using available_externally (existing functionality implemented for modular code generation). The pch-codegen test has been updated to reflect this new behavior.

[If possible: I'd love it if we could not have the extra MSVC-style way of accessing dllexport-pch-homing, and just do it the modular codegen way, but I understand that it might be a limitation of existing build systems. @hans / @thakis: Do either of you know if it'd be practical to move to something more similar to .pcm handling, where the pch itself is passed to the compilation, rather than homed as a side effect of compiling some other source file?]

Reviewers: llunak, hans

Differential Revision: https://reviews.llvm.org/D83652
2020-07-22 12:46:12 -07:00
Luboš Luňák
31b05692cd make -fmodules-codegen and -fmodules-debuginfo work also with PCHs
Allow to build PCH's (with -building-pch-with-obj and the extra .o file)
with -fmodules-codegen -fmodules-debuginfo to allow emitting shared code
into the extra .o file, similarly to how it works with modules. A bit of
a misnomer, but the underlying functionality is the same. This saves up
to 20% of build time here. The patch is fairly simple, it basically just
duplicates -fmodules checks to also alternatively check
-building-pch-with-obj.

This already got committed as cbc9d22e49b434b6ceb2eb94b67079d02e0a7b74,
but then got reverted in 7ea9a6e0220da36ff2fd1fbc29c2755be23e5166
because of PR44953, as discussed in D74846. This is a corrected version
which does not include two places for the PCH case that aren't included
in the modules -fmodules-codegen path either.

Differential Revision: https://reviews.llvm.org/D69778
2020-07-09 15:22:26 +02:00
Daniel Grumberg
bb8c7e756c Add AST_SIGNATURE record to unhashed control block of PCM files
Summary:
This record is constructed by hashing the bytes of the AST block in a similiar
fashion to the SIGNATURE record. This new signature only means anything if the
AST block is fully relocatable, i.e. it does not embed absolute offsets within
the PCM file. This change ensure this does not happen by replacing these offsets
with offsets relative to the nearest relevant subblock of the AST block.

Reviewers: Bigcheese, dexonsmith

Subscribers: dexonsmith, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D80383
2020-06-11 14:09:07 +01:00
David Goldman
8b529e311a [ObjC] Fix AST serialization for pseudo-strong parameters
This bit was assumed to be always false for ParmVarDecls, but attribute
objc_externally_retained now can produce it.

Differential revision: https://reviews.llvm.org/D74417
2020-06-08 11:54:01 -04:00
Dmitry Polukhin
a7afb211dc [clang][AST] Support AST files larger than 512M
Summary:
Clang uses 32-bit integers for storing bit offsets from the beginning of
the file that results in 512M limit on AST file. This diff replaces
absolute offsets with relative offsets from the beginning of
corresponding data structure when it is possible. And uses 64-bit
offsets for DeclOffests and TypeOffssts because these coder AST
section may easily exceeds 512M alone.

This diff breaks AST file format compatibility so VERSION_MAJOR bumped.

Test Plan:
Existing clang AST serialization tests
Tested on clangd with ~700M and ~900M preamble files
check-clang with ubsan

Reviewers: rsmith, dexonsmith

Subscribers: ilya-biryukov, kadircet, usaxena95, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D76594
2020-04-17 06:17:33 -07:00
Dmitry Polukhin
a8f85da9f5 Revert "[clang][AST] Support AST files larger than 512M"
Bitcode file alignment is only 32-bit so 64-bit offsets need
special handling.
/b/sanitizer-x86_64-linux-fast/build/llvm-project/clang/lib/Serialization/ASTReader.cpp:6327:28: runtime error: load of misaligned address 0x7fca2bcfe54c for type 'const uint64_t' (aka 'const unsigned long'), which requires 8 byte alignment
0x7fca2bcfe54c: note: pointer points here
  00 00 00 00 5a a6 01 00  00 00 00 00 19 a7 01 00  00 00 00 00 48 a7 01 00  00 00 00 00 7d a7 01 00
              ^
    #0 0x3be2fe4 in clang::ASTReader::TypeCursorForIndex(unsigned int) /b/sanitizer-x86_64-linux-fast/build/llvm-project/clang/lib/Serialization/ASTReader.cpp:6327:28
    #1 0x3be30a0 in clang::ASTReader::readTypeRecord(unsigned int) /b/sanitizer-x86_64-linux-fast/build/llvm-project/clang/lib/Serialization/ASTReader.cpp:6348:24
    #2 0x3bd3d4a in clang::ASTReader::GetType(unsigned int) /b/sanitizer-x86_64-linux-fast/build/llvm-project/clang/lib/Serialization/ASTReader.cpp:6985:26
    #3 0x3c5d9ae in clang::ASTDeclReader::Visit(clang::Decl*) /b/sanitizer-x86_64-linux-fast/build/llvm-project/clang/lib/Serialization/ASTReaderDecl.cpp:533:31
    #4 0x3c91cac in clang::ASTReader::ReadDeclRecord(unsigned int) /b/sanitizer-x86_64-linux-fast/build/llvm-project/clang/lib/Serialization/ASTReaderDecl.cpp:4045:10
    #5 0x3bd4fb1 in clang::ASTReader::GetDecl(unsigned int) /b/sanitizer-x86_64-linux-fast/build/llvm-project/clang/lib/Serialization/ASTReader.cpp:7352:5
    #6 0x3bce2f9 in clang::ASTReader::ReadASTBlock(clang::serialization::ModuleFile&, unsigned int) /b/sanitizer-x86_64-linux-fast/build/llvm-project/clang/lib/Serialization/ASTReader.cpp:3625:22
    #7 0x3bd6d75 in clang::ASTReader::ReadAST(llvm::StringRef, clang::serialization::ModuleKind, clang::SourceLocation, unsigned int, llvm::SmallVectorImpl<clang::ASTReader::ImportedSubmodule>*) /b/sanitizer-x86_64-linux-fast/build/llvm-project/clang/lib/Serialization/ASTReader.cpp:4230:32
    #8 0x3a6b415 in clang::CompilerInstance::createPCHExternalASTSource(llvm::StringRef, llvm::StringRef, bool, bool, clang::Preprocessor&, clang::InMemoryModuleCache&, clang::ASTContext&, clang::PCHContainerReader const&, llvm::ArrayRef<std::shared_ptr<clang::ModuleFileExtension> >, llvm::ArrayRef<std::shared_ptr<clang::DependencyCollector> >, void*, bool, bool, bool) /b/sanitizer-x86_64-linux-fast/build/llvm-project/clang/lib/Frontend/CompilerInstance.cpp:539:19
    #9 0x3a6b00e in clang::CompilerInstance::createPCHExternalASTSource(llvm::StringRef, bool, bool, void*, bool) /b/sanitizer-x86_64-linux-fast/build/llvm-project/clang/lib/Frontend/CompilerInstance.cpp:501:18
    #10 0x3abac80 in clang::FrontendAction::BeginSourceFile(clang::CompilerInstance&, clang::FrontendInputFile const&) /b/sanitizer-x86_64-linux-fast/build/llvm-project/clang/lib/Frontend/FrontendAction.cpp:865:12
    #11 0x3a6e61c in clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) /b/sanitizer-x86_64-linux-fast/build/llvm-project/clang/lib/Frontend/CompilerInstance.cpp:972:13
    #12 0x3ba74bf in clang::ExecuteCompilerInvocation(clang::CompilerInstance*) /b/sanitizer-x86_64-linux-fast/build/llvm-project/clang/lib/FrontendTool/ExecuteCompilerInvocation.cpp:282:25
    #13 0xa3f753 in cc1_main(llvm::ArrayRef<char const*>, char const*, void*) /b/sanitizer-x86_64-linux-fast/build/llvm-project/clang/tools/driver/cc1_main.cpp:240:15
    #14 0xa3a68a in ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&) /b/sanitizer-x86_64-linux-fast/build/llvm-project/clang/tools/driver/driver.cpp:330:12
    #15 0xa37f31 in main /b/sanitizer-x86_64-linux-fast/build/llvm-project/clang/tools/driver/driver.cpp:407:12
    #16 0x7fca2a7032e0 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x202e0)
    #17 0xa21029 in _start (/b/sanitizer-x86_64-linux-fast/build/llvm_build_ubsan/bin/clang-11+0xa21029)

This reverts commit 30d5946db95fa465d7ee6caceb2b1ff191e3727c.
2020-04-16 09:09:38 -07:00
Dmitry Polukhin
30d5946db9 [clang][AST] Support AST files larger than 512M
Summary:
Clang uses 32-bit integers for storing bit offsets from the beginning of
the file that results in 512M limit on AST file. This diff replaces
absolute offsets with relative offsets from the beginning of
corresponding data structure when it is possible. And uses 64-bit
offsets for DeclOffests and TypeOffssts because these coder AST
section may easily exceeds 512M alone.

This diff breaks AST file format compatibility so VERSION_MAJOR bumped.

Test Plan:
Existing clang AST serialization tests
Tested on clangd with ~700M and ~900M preamble files

Reviewers: rsmith, dexonsmith

Subscribers: ilya-biryukov, kadircet, usaxena95, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D76594
2020-04-16 07:27:43 -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
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
Haojian Wu
4b0f1e12c2 [AST] Add a flag indicating if any subexpression had errors
The only subexpression that is considered an error now is TypoExpr, but
we plan to add expressions with errors to improve editor tooling on broken
code. We intend to use the same mechanism to guard against spurious
diagnostics on those as well.

See the follow-up revision for an actual usage of the flag.

Original patch from Ilya.

Reviewers: sammccall

Reviewed By: sammccall

Tags: #clang

Differential Revision: https://reviews.llvm.org/D65591
2020-03-19 08:56:10 +01:00
Roman Lebedev
d5edcb9064
[clang] Prune 'IsOMPStructuredBlock' Stmt bit
As discussed in https://reviews.llvm.org/D59214#1916596
and in some other reviews dealing with FPenv,
bits in Stmt are scarce, and i got so burnout with D59214
and https://bugs.llvm.org/show_bug.cgi?id=40563 specifically
that i never actually followed up with the usages for this bit.

So let's unhoard it, at least for now?
2020-03-12 14:48:57 +03:00
Hans Wennborg
7ea9a6e022 Revert "make -fmodules-codegen and -fmodules-debuginfo work also with PCHs"
This caused PR44953. See also the discussion on D74846.

This reverts commit cbc9d22e49b434b6ceb2eb94b67079d02e0a7b74.
2020-02-27 14:33:43 +01:00
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 e57a9abc4b01fa69fe81ace8df70517983b6cbac.

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 e03ead6771fc97b11cb0c94b7f023142184ad25f
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 027931899763409e2c61a84bdee6057b5e838ffa.

There have been some failing tests on some platforms, reverting while investigating.
2020-01-18 14:58:01 +02:00