Richard Smith [Thu, 5 Sep 2019 01:23:47 +0000 (01:23 +0000)]
[c++20] Fix some ambiguities in our mangling of lambdas with explicit
template parameters.
This finishes the implementation of the proposal described in
https://github.com/itanium-cxx-abi/cxx-abi/issues/31. (We already
implemented the <lambda-sig> extensions, but didn't take them into
account when computing mangling numbers, and didn't deal properly with
expanded parameter packs, and didn't disambiguate between different
levels of template parameters in manglings.)
Richard Smith [Wed, 4 Sep 2019 20:30:37 +0000 (20:30 +0000)]
[c++20] P1143R2: Add support for the C++20 'constinit' keyword.
This is mostly the same as the
[[clang::require_constant_initialization]] attribute, but has a couple
of additional syntactic and semantic restrictions.
In passing, I added a warning for the attribute form being added after
we have already seen the initialization of the variable (but before we
see the definition); that case previously slipped between the cracks and
the attribute was silently ignored.
Leonard Chan [Wed, 4 Sep 2019 20:30:29 +0000 (20:30 +0000)]
[NewPM][Sancov] Make Sancov a Module Pass instead of 2 Passes
This patch merges the sancov module and funciton passes into one module pass.
The reason for this is because we ran into an out of memory error when
attempting to run asan fuzzer on some protobufs (pc.cc files). I traced the OOM
error to the destructor of SanitizerCoverage where we only call
appendTo[Compiler]Used which calls appendToUsedList. I'm not sure where precisely
in appendToUsedList causes the OOM, but I am able to confirm that it's calling
this function *repeatedly* that causes the OOM. (I hacked sancov a bit such that
I can still create and destroy a new sancov on every function run, but only call
appendToUsedList after all functions in the module have finished. This passes, but
when I make it such that appendToUsedList is called on every sancov destruction,
we hit OOM.)
I don't think the OOM is from just adding to the SmallSet and SmallVector inside
appendToUsedList since in either case for a given module, they'll have the same
max size. I suspect that when the existing llvm.compiler.used global is erased,
the memory behind it isn't freed. I could be wrong on this though.
This patch works around the OOM issue by just calling appendToUsedList at the
end of every module run instead of function run. The same amount of constants
still get added to llvm.compiler.used, abd we make the pass usage and logic
simpler by not having any inter-pass dependencies.
Generate parent context id from Decl* instead of DeclContext*.
Because of multiple inheritance, a DeclContext pointer does not produce
the same pointer representation as a Decl pointer that references the
same AST Node.
When dumping the parentDeclContextId field of a node, convert the pointer
to Decl* first, so the id can be used to find the AST node it references.
[ASTImporter] Added visibility context check for TypedefNameDecl.
Summary:
ASTImporter makes now difference between typedefs and type aliases
with same name in different translation units
if these are not visible outside.
Jinsong Ji [Wed, 4 Sep 2019 14:01:47 +0000 (14:01 +0000)]
[PowerPC][Altivec] Fix constant argument for vec_dss
Summary:
This is similar to vec_ct* in https://reviews.llvm.org/rL304205.
The argument must be a constant, otherwise instruction selection
will fail. always_inline is not enough for isel to always fold
everything away at -O0.
The fix is to turn the function into macros in altivec.h.
Hans Wennborg [Wed, 4 Sep 2019 08:19:30 +0000 (08:19 +0000)]
Re-commit r363191 "[MS] Pretend constexpr variable template specializations are inline"
While the next Visual Studio update (16.3) will fix this issue, that hasn't
shipped yet. Until then Clang wouldn't work with MSVC's headers which seems
unfortunate. Let's keep this in until VS 16.3 ships. (See also PR42843.)
> Fixes link errors with clang and the latest Visual C++ 14.21.27702
> headers, which was reported as PR42027.
>
> I chose to intentionally make these things linkonce_odr, i.e.
> discardable, so that we don't emit definitions of these things in every
> translation unit that includes STL headers.
>
> Note that this is *not* what MSVC does: MSVC has not yet implemented C++
> DR2387, so they emit fully specialized constexpr variable templates with
> static / internal linkage.
>
> Reviewers: rsmith
>
> Differential Revision: https://reviews.llvm.org/D63175
[Clang Interpreter] Initial patch for the constexpr interpreter
Summary:
This patch introduces the skeleton of the constexpr interpreter,
capable of evaluating a simple constexpr functions consisting of
if statements. The interpreter is described in more detail in the
RFC. Further patches will add more features.
[analyzer] NonNullParamChecker and CStringChecker parameter number in checker message
There are some functions which can't be given a null pointer as parameter either
because it has a nonnull attribute or it is declared to have undefined behavior
(e.g. strcmp()). Sometimes it is hard to determine from the checker message
which parameter is null at the invocation, so now this information is included
in the message.
This commit fixes https://bugs.llvm.org/show_bug.cgi?id=39358
[CUDA] Use activemask.b32 instruction to implement __activemask w/ CUDA-9.2+
vote.ballot instruction is gone in recent CUDA versions and
vote.sync.ballot can not be used because it needs a thread mask parameter.
Fortunately PTX 6.2 (introduced with CUDA-9.2) provides activemask.b32
instruction for this.
Ed Maste [Tue, 3 Sep 2019 16:30:21 +0000 (16:30 +0000)]
clang: default to DWARF 4 for FreeBSD 12.0 and later
Older FreeBSD versions included GDB 6.1 and had other tools that were
unable to handle debug information newer than DWARF 2. Those tools have
since been updated. (An old version of GDB is still kept for kernel
crash handling, but the kernel is compiled with an explicit -gdwarf2.)
Reviewed by: dim
Differential Revision: https://reviews.llvm.org/D66760
[analyzer] Add a checker option to detect nested dead stores
Enables the users to specify an optional flag which would warn for more dead
stores.
Previously it ignored if the dead store happened e.g. in an if condition.
if ((X = generate())) { // dead store to X
}
This patch introduces the `WarnForDeadNestedAssignments` option to the checker,
which is `false` by default - so this change would not affect any previous
users.
I have updated the code, tests and the docs as well. If I missed something, tell
me.
I also ran the analysis on Clang which generated 14 more reports compared to the
unmodified version. All of them seemed reasonable for me.
Related previous patches:
rGf224820b45c6847b91071da8d7ade59f373b96f3
Summary:
The declaration of arm neon intrinsics that are
"big endian safe" print the same code for big
and small endian targets.
This patch avoids duplicates by checking if an
intrinsic is safe to have a single definition.
(decreases header 11k lines out of 73k).
Sam Elliott [Tue, 3 Sep 2019 08:47:58 +0000 (08:47 +0000)]
[RISCV] Correct Logic around ilp32e macros
Summary:
GCC seperates the `__riscv_float_abi_*` macros and the
`__riscv_abi_rve` macro. If the chosen abi is ilp32e, `gcc -march=rv32i
-mabi=ilp32i -E -dM` shows that both `__riscv_float_abi_soft` and
`__riscv_abi_rve` are set.
This patch corrects the compiler logic around these defines.
At the moment, this patch will not change clang's behaviour, because we do not
accept the `ilp32e` abi yet.
Dmitri Gribenko [Mon, 2 Sep 2019 18:24:33 +0000 (18:24 +0000)]
[Wdocumentation] fixes an assertion failure with typedefed function and block pointer
Summary:
The assertion happens when compiling with -Wdocumentation with variable declaration to a typedefed function pointer. I not too familiar with the ObjC syntax but first two tests assert without this patch.
[AST] AST structural equivalence to work internally with pairs.
Summary:
The structural equivalence check stores now pairs of nodes in the
'from' and 'to' context instead of only the node in 'from' context
and a corresponding one in 'to' context. This is needed to handle
cases when a Decl in the 'from' context is to be compared with
multiple Decls in the 'to' context.
[Clang Interpreter] Initial patch for the constexpr interpreter
Summary:
This patch introduces the skeleton of the constexpr interpreter,
capable of evaluating a simple constexpr functions consisting of
if statements. The interpreter is described in more detail in the
RFC. Further patches will add more features.
David Bolvansky [Sat, 31 Aug 2019 18:52:44 +0000 (18:52 +0000)]
[clang] Devirtualization for classes with destructors marked as 'final'
A class with a destructor marked final cannot be derived from, so it should afford the same devirtualization opportunities as marking the entire class final.
David Bolvansky [Sat, 31 Aug 2019 18:31:19 +0000 (18:31 +0000)]
[clang] Warning for non-final classes with final destructors
Marking a class' destructor final prevents the class from being inherited from. However, it is a subtle and awkward way to express that at best, and unintended at worst. It may also generate worse code (in other compilers) than marking the class itself final. For these reasons, this revision adds a warning for nonfinal classes with final destructors, with a note to suggest marking the class final to silence the warning.
See https://reviews.llvm.org/D66621 for more background.
Nandor Licker [Sat, 31 Aug 2019 15:00:38 +0000 (15:00 +0000)]
[Clang Interpreter] Initial patch for the constexpr interpreter
Summary:
This patch introduces the skeleton of the constexpr interpreter,
capable of evaluating a simple constexpr functions consisting of
if statements. The interpreter is described in more detail in the
RFC. Further patches will add more features.
Alex Lorenz [Sat, 31 Aug 2019 01:26:04 +0000 (01:26 +0000)]
Introduce a DirectoryEntryRef that stores both a reference and an
accessed name to the directory entry
This commit introduces a parallel API that returns a DirectoryEntryRef
to the FileManager, similar to the parallel FileEntryRef API. All
uses will have to be update in follow-up patches. The immediate use of the new API in this
patch fixes the issue where a file manager was reused in clang-scan-deps,
but reported an different file path whenever a framework lookup was done through a symlink.
Thomas Lively [Sat, 31 Aug 2019 00:12:29 +0000 (00:12 +0000)]
[WebAssembly] Add SIMD QFMA/QFMS
Summary:
Adds clang builtins and LLVM intrinsics for these experimental
instructions. They are not implemented in engines yet, but that is ok
because the user must opt into using them by calling the builtins.
Richard Smith [Sat, 31 Aug 2019 00:05:50 +0000 (00:05 +0000)]
[c++20] Disallow template argument deduction from a braced-init-list
containing designators. The C++20 wording doesn't actually say what
happens in this case, but treating this as a non-deduced context seems
like the most natural behavior.
(We might want to consider deducing through array designators as an
extension in the future, but will need to be careful to deduce the array
bound properly if we do so. That's not permitted herein.)
ASTReader: Bypass overridden files when reading PCHs
If contents of a file that is part of a PCM are overridden when reading
it, but weren't overridden when the PCM was being built, the ASTReader
will emit an error. Now it creates a separate FileEntry for recovery,
bypassing the overridden content instead of discarding it. The
pre-existing testcase clang/test/PCH/remap-file-from-pch.cpp confirms
that the new recovery method works correctly.
This resolves a long-standing FIXME to avoid hypothetically invalidating
another precompiled module that's already using the overridden contents.
This also removes ContentCache-related API that would be unsafe to use
across `CompilerInstance`s in an implicit modules build. This helps to
unblock us sinking it from SourceManager into FileManager in the future,
which would allow us to delete `InMemoryModuleCache`.
Richard Smith [Fri, 30 Aug 2019 22:52:55 +0000 (22:52 +0000)]
[c++20] Implement semantic restrictions for C++20 designated
initializers.
This has some interesting interactions with our existing extensions to
support C99 designated initializers as an extension in C++. Those are
resolved as follows:
* We continue to permit the full breadth of C99 designated initializers
in C++, with the exception that we disallow a partial overwrite of an
initializer with a non-trivially-destructible type. (Full overwrite
is OK, because we won't run the first initializer at all.)
* The C99 extensions are disallowed in SFINAE contexts and during
overload resolution, where they could change the meaning of valid
programs.
* C++20 disallows reordering of initializers. We only check for that for
the simple cases that the C++20 rules permit (designators of the form
'.field_name =' and continue to allow reordering in other cases).
It would be nice to improve this behavior in future.
* All C99 designated initializer extensions produce a warning by
default in C++20 mode. People are going to learn the C++ rules based
on what Clang diagnoses, so it's important we diagnose these properly
by default.
* In C++ <= 17, we apply the C++20 rules rather than the C99 rules, and
so still diagnose C99 extensions as described above. We continue to
accept designated C++20-compatible initializers in C++ <= 17 silently
by default (but naturally still reject under -pedantic-errors).
This is not a complete implementation of P0329R4. In particular, that
paper introduces new non-C99-compatible syntax { .field { init } }, and
we do not support that yet.
This is based on a previous patch by Don Hinton, though I've made
substantial changes when addressing the above interactions.
Nandor Licker [Fri, 30 Aug 2019 21:17:03 +0000 (21:17 +0000)]
[Clang Interpreter] Initial patch for the constexpr interpreter
Summary:
This patch introduces the skeleton of the constexpr interpreter,
capable of evaluating a simple constexpr functions consisting of
if statements. The interpreter is described in more detail in the
RFC. Further patches will add more features.
There's no need to purge symlinked entries in the FileManager,
as the new FileEntryRef API allows us to compute dependencies more
accurately when the FileManager is reused.
Nandor Licker [Fri, 30 Aug 2019 15:02:09 +0000 (15:02 +0000)]
[Clang Interpreter] Initial patch for the constexpr interpreter
Summary:
This patch introduces the skeleton of the constexpr interpreter,
capable of evaluating a simple constexpr functions consisting of
if statements. The interpreter is described in more detail in the
RFC. Further patches will add more features.
Gabor Marton [Fri, 30 Aug 2019 10:55:41 +0000 (10:55 +0000)]
[ASTImporter] Do not look up lambda classes
Summary:
Consider this code:
```
void f() {
auto L0 = [](){};
auto L1 = [](){};
}
```
First we import `L0` then `L1`. Currently we end up having only one
CXXRecordDecl for the two different lambdas. And that is a problem if
the body of their op() is different. This happens because when we import
`L1` then lookup finds the existing `L0` and since they are structurally
equivalent we just map the imported L0 to be the counterpart of L1.
We have the same problem in this case:
```
template <typename F0, typename F1>
void f(F0 L0 = [](){}, F1 L1 = [](){}) {}
```
In StructuralEquivalenceContext we could distinquish lambdas only by
their source location in these cases. But we the lambdas are actually
structrually equivalent they differn only by the source location.
Thus, the solution is to disable lookup completely if the decl in
the "from" context is a lambda.
However, that could have other problems: what if the lambda is defined
in a header file and included in several TUs? I think we'd have as many
duplicates as many includes we have. I think we could live with that,
because the lambda classes are TU local anyway, we cannot just access
them from another TU.
Balazs Keri [Fri, 30 Aug 2019 10:12:14 +0000 (10:12 +0000)]
[ASTImporter] Propagate errors during import of overridden methods.
Summary:
If importing overridden methods fails for a method it can be seen
incorrectly as non-virtual. To avoid this inconsistency the method
is marked with import error to avoid later use of it.
[CodeGen]: fix error message for "=r" asm constraint
Summary:
Nico Weber reported that the following code:
char buf[9];
asm("" : "=r" (buf));
yields the "impossible constraint in asm: can't store struct into a register"
error message, although |buf| is not a struct (see
http://crbug.com/999160).
Make the error message more generic and add a test for it.
Also make sure other tests in x86_64-PR42672.c check for the full error
message.
Alex Lorenz [Fri, 30 Aug 2019 01:25:57 +0000 (01:25 +0000)]
[clang-scan-deps] NFC, refactor the DependencyScanningWorker to use a consumer
to report the dependencies to the client
This will allow the scanner to report modular dependencies to the consumer.
This will also allow the scanner to accept regular cc1 clang invocations, e.g.
in an implementation of a libclang C API for clang-scan-deps, that I will add
follow-up patches for in the future.
[Modules] Make ReadModuleMapFileBlock errors reliable
This prevents a crash when an error should be emitted instead.
During implicit module builds, there are cases where ReadASTCore is called with
ImportedBy set to nullptr, which breaks expectations in ReadModuleMapFileBlock,
leading to crashes.
Fix this by improving ReadModuleMapFileBlock to handle ImportedBy correctly.
This only happens non deterministically in the wild, when the underlying file
system changes while concurrent compiler invocations use implicit modules,
forcing rebuilds which see an inconsistent filesystem state. That said, there's
no much to do w.r.t. writing tests here.
Alex Lorenz [Thu, 29 Aug 2019 22:56:38 +0000 (22:56 +0000)]
[clang-scan-deps] reuse the file manager across invocations of
the dependency scanner on a single worker thread
This behavior can be controlled using the new `-reuse-filemanager` clang-scan-deps
option. By default the file manager is reused.
The added test/ClangScanDeps/symlink.cpp is able to pass with
the reused filemanager after the related FileEntryRef changes
landed earlier. The test test/ClangScanDeps/subframework_header_dir_symlink.m
still fails when the file manager is reused (I run the FileCheck with not to
make it PASS). I will address this in a follow-up patch that improves
the DirectoryEntry name modelling in the FileManager.
Richard Smith [Thu, 29 Aug 2019 22:49:34 +0000 (22:49 +0000)]
Fix silent wrong-code bugs and crashes with designated initialization.
We failed to correctly handle the 'holes' left behind by designated
initializers in VerifyOnly mode. This would result in us thinking that a
designated initialization would be valid, only to find that it is not
actually valid when we come to build it. In a +Asserts build, that would
assert, and in a -Asserts build, that would silently lose some part of
the initialization or crash.
With this change, when an InitListExpr contains any designators, we now
always build a structured list so that we can track the locations of the
'holes' that we need to go back and fill in.
We could in principle do better: we only need the structured form if
there is a designator that jumps backwards (and can otherwise check for
the holes as we progress through the initializer list), but dealing with
that turns out to be rather complicated, so it's not done as part of
this patch.
Richard Smith [Thu, 29 Aug 2019 22:49:33 +0000 (22:49 +0000)]
Refactor InitListChecker to check only a single (explicit) initializer
list, rather than recursively checking multiple lists in C.
This simplification is in preparation for making InitListChecker
maintain more state that's specific to the explicit initializer list,
particularly when handling designated initialization.
Richard Smith [Thu, 29 Aug 2019 22:49:32 +0000 (22:49 +0000)]
Refactor InitListChecker to make it a bit clearer that hasError is only
set to true in VerifyOnly mode in cases where it's also set to true when
actually building the initializer list.
Add FIXMEs for the two cases where that's not true. No functionality
change intended.
Artem Dergachev [Thu, 29 Aug 2019 20:37:28 +0000 (20:37 +0000)]
[CFG] Fix CFG for statement-expressions in return values.
We're building the CFG from bottom to top, so when the return-value expression
has a non-trivial CFG on its own, we need to continue building from the entry
to the return-value expression CFG rather than from the block to which
we've just appended the return statement.
Fixes a false positive warning "control may reach end of non-void function".
Craig Topper [Thu, 29 Aug 2019 18:09:02 +0000 (18:09 +0000)]
[X86] Remove what little support we had for MPX
-Deprecate -mmpx and -mno-mpx command line options
-Remove CPUID detection of mpx for -march=native
-Remove MPX from all CPUs
-Remove MPX preprocessor define
I've left the "mpx" string in the backend so we don't fail on old IR, but its not connected to anything.
gcc has also deprecated these command line options. https://www.phoronix.com/scan.php?page=news_item&px=GCC-Patch-To-Drop-MPX
[CodeGen]: don't treat structures returned in registers as memory inputs
Summary:
The "=r" output constraint for a structure variable passed to inline asm
shouldn't be converted to "=*r", as this changes the asm directive
semantics and prevents DSE optimizations.
Instead, preserve the constraints and return such structures as integers
of corresponding size, which are converted back to structures when
storing the result.
Dmitri Gribenko [Thu, 29 Aug 2019 10:23:29 +0000 (10:23 +0000)]
[Index] Create PP callbacks in the ASTConsumer
Doing so removes one reason to create a custom FrontendAction.
FrontendActions are not desirable because they are difficult to compose.
ASTConsumers are much easier to compose.
[OpenCL] Fix diagnosing enqueue_kernel call with too few args
The err_typecheck_call_too_few_args diagnostic takes arguments, but
none were provided causing clang to crash when attempting to diagnose
an enqueue_kernel call with too few arguments.
Adam Balogh [Thu, 29 Aug 2019 09:35:47 +0000 (09:35 +0000)]
[Analyzer] Iterator Checkers - Make range errors and invalidated access fatal
Range errors (dereferencing or incrementing the past-the-end iterator or
decrementing the iterator of the first element of the range) and access of
invalidated iterators lead to undefined behavior. There is no point to
continue the analysis after such an error on the same execution path, but
terminate it by a sink node (fatal error). This also improves the
performance and helps avoiding double reports (e.g. in case of nested
iterators).
Volodymyr Sapsai [Wed, 28 Aug 2019 23:31:32 +0000 (23:31 +0000)]
[Modules] Fix rebuilding an updated module for each of its consumers.
Marking a module for a rebuild when its signature differs from the
expected one causes redundant module rebuilds for incremental builds.
When a module is updated, its signature changes. But its consumers still
have the old signature and loading them will result in signature
mismatches. It will correctly cause the rebuilds for the consumers but
we don't need to rebuild the common module for each of them as it is
already up to date.
In practice this bug causes longer build times. We are doing more work
than required and only a single process can build a module, so parallel
builds degrade to a single-process mode where extra processes are just
waiting on a file lock.
Fix by not marking a module dependency for a rebuild on signature
mismatch. We'll check if it is up to date when we load it.
projects / clang / log