Erich Keane [Wed, 19 Apr 2017 21:24:55 +0000 (21:24 +0000)]
Corrrect warn_unused_result attribute
The original idea was that if the attribute on an operator,
that the return-value unused-ness wouldn't matter. However,
all of the operators except postfix inc/dec return
references! References don't result in this warning
anyway, so those are already excluded.
[CodeGen] Use preincrement version of APInt::operator++ instead of postincrement to avoid creating and immediately discarding a temporary APInt.
This is preparation for a clang change to improve the [[nodiscard]] warning to not be ignored on methods that return a class marked [[nodiscard]] that are defined in the class itself. See D32207.
[Coverage] Don't emit mappings for functions in dependent contexts (fixes PR32679)
The coverage implementation marks functions which won't be emitted as
'deferred', so that it can emit empty coverage regions for them later
(once their linkages are known).
Functions in dependent contexts are an exception: if there isn't a full
instantiation of a function, it shouldn't be marked 'deferred'. We've
been breaking that rule without much consequence because we just ended
up with useless, extra, empty coverage mappings. With PR32679, this
behavior finally caused a crash, because clang marked a partial template
specialization as 'deferred', causing the MS mangler to choke in its
delayed-template-parsing mode:
error: cannot mangle this template type parameter type yet
(http://bugs.llvm.org/show_bug.cgi?id=32679)
Fix this by checking if a decl's context is a dependent context before
marking it 'deferred'.
Prefer addAttr(Attribute::AttrKind) over the AttributeList overload
This should simplify the call sites, which typically want to tweak one
attribute at a time. It should also avoid creating ephemeral
AttributeLists that live forever.
Alex Lorenz [Wed, 19 Apr 2017 15:52:11 +0000 (15:52 +0000)]
Add #pragma clang attribute support to the external_source_symbol attribute
Prior to this commit the external_source_symbol attribute wasn't supported by
#pragma clang attribute for the following two reasons:
- The Named attribute subject hasn't been supported by TableGen.
- There was no way to specify a subject match rule for #pragma clang attribute
that could operate on a set of attribute subjects (e.g. the ones that derive
from NamedDecl).
This commit fixes the two issues and thus adds external_source_symbol support to
#pragma clang attribute.
Alex Lorenz [Wed, 19 Apr 2017 08:58:56 +0000 (08:58 +0000)]
Add support for editor placeholders to Clang
This commit teaches Clang to recognize editor placeholders that are produced
when an IDE like Xcode inserts a code-completion result that includes a
placeholder. Now when the lexer sees a placeholder token, it emits an
'editor placeholder in source file' error and creates an identifier token
that represents the placeholder. The parser/sema can now recognize the
placeholders and can suppress the diagnostics related to the placeholders. This
ensures that live issues in an IDE like Xcode won't get spurious diagnostics
related to placeholders.
This commit also adds a new compiler option named '-fallow-editor-placeholders'
that silences the 'editor placeholder in source file' error. This is useful
for an IDE like Xcode as we don't want to display those errors in live issues.
Revert r300653 and r300650. The underlying commit fixes one issue with
modules but exposes much more widespread issues. Example and more
information is on the review thread for r300650.
Original commit summary:
[modules] Properly look up the owning module for an instantiation of a merged template.
Richard Smith [Wed, 19 Apr 2017 01:36:43 +0000 (01:36 +0000)]
[modules] Properly look up the owning module for an instantiation of a merged template.
When looking for the template instantiation pattern of a templated entity,
consistently select the definition of the pattern if there is one. This means
we'll pick the same owning module when we start instantiating a template that
we'll later pick when determining which modules are visible during that
instantiation.
Richard Smith [Tue, 18 Apr 2017 21:55:37 +0000 (21:55 +0000)]
[modules-ts] Fold together -x c++ and -x c++-module at -cc1 level.
The driver needs to know whether it's building a module interface or
implementation unit because it affects which outputs it produces and how it
builds the command pipeline. But the frontend doesn't need to know and should
not care: all it needs to know is what action it is being asked to perform on
the input.
(This is in preparation for permitting -emit-obj to be used on a module
interface unit to produce object code without going via a "full" PCM file.)
Alex Lorenz [Tue, 18 Apr 2017 20:54:23 +0000 (20:54 +0000)]
The SubjectMatchRule enum should not be used as a DenseMap key to avoid
UBSAN 'invalid value' failures
The commit r300556 introduced a UBSAN issue that was caught by
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-bootstrap. The DenseMap
failed to create an empty/tombstone value as the empty/tombstone values for the
SubjectMatchRule enum were not valid enum constants.
Alex Lorenz [Tue, 18 Apr 2017 14:33:39 +0000 (14:33 +0000)]
Add #pragma clang attribute
This is a recommit of r300539 that was reverted in r300543 due to test failures.
The original commit message is displayed below:
The new '#pragma clang attribute' directive can be used to apply attributes to
multiple declarations. An attribute must satisfy the following conditions to
be supported by the pragma:
- It must have a subject list that's defined in the TableGen file.
- It must be documented.
- It must not be late parsed.
- It must have a GNU/C++11 spelling.
Oliver Stannard [Tue, 18 Apr 2017 13:21:05 +0000 (13:21 +0000)]
[ARM] Add hardware build attributes in assembler
This passes an option to the ARM assembly parser to emit build
attributes for the hardware selected by command line options, when
assembling an assembly file.
This is not enabled for C/C++, as this would result in duplicate build
attribute directives being emitted in each inline assembly block, when
emitting assembly.
This also adds an option to allow disabling this behaviour for assembly
files, for users who were relying on the old behaviour.
Alex Lorenz [Tue, 18 Apr 2017 09:41:47 +0000 (09:41 +0000)]
Add #pragma clang attribute
The new '#pragma clang attribute' directive can be used to apply attributes to
multiple declarations. An attribute must satisfy the following conditions to
be supported by the pragma:
- It must have a subject list that's defined in the TableGen file.
- It must be documented.
- It must not be late parsed.
- It must have a GNU/C++11 spelling.
Eric Fiselier [Tue, 18 Apr 2017 03:12:48 +0000 (03:12 +0000)]
[coroutines] Fix building of new/delete expressions when get_return_object_on_allocation_failure() is present.
Summary:
This patch implements [dcl.fct.def.coroutine]p8:
> The unqualified-id get_return_object_on_allocation_failure is looked up in the scope of
> class P by class member access lookup (3.4.5). If a declaration is found, ..., and if a
> global allocation function is selected, the ::operator new(size_t, nothrow_t) form shall be used.
> [...]
> The allocation function used in this case must have a non-throwing noexcept-specification.
Adrian Prantl [Tue, 18 Apr 2017 01:22:01 +0000 (01:22 +0000)]
Debug Info: Remove special-casing of indirect function argument handling.
LLVM has changed the semantics of dbg.declare for describing function
arguments. After this patch a dbg.declare always takes the *address*
of a variable as the first argument, even if the argument is not an
alloca.
Richard Smith [Mon, 17 Apr 2017 23:44:51 +0000 (23:44 +0000)]
Fix mishandling of escaped newlines followed by newlines or nuls.
Previously, if an escaped newline was followed by a newline or a nul, we'd lex
the escaped newline as a bogus space character. This led to a bunch of
different broken corner cases:
For the pattern "\\\n\0#", we would then have a (horizontal) space whose
spelling ends in a newline, and would decide that the '#' is at the start of a
line, and incorrectly start preprocessing a directive in the middle of a
logical source line. If we were already in the middle of a directive, this
would result in our attempting to process multiple directives at the same time!
This resulted in crashes, asserts, and hangs on invalid input, as discovered by
fuzz-testing.
For the pattern "\\\n" at EOF (with an implicit following nul byte), we would
produce a bogus trailing space character with spelling "\\\n". This was mostly
harmless, but would lead to clang-format getting confused and misformatting in
rare cases. We now produce a trailing EOF token with spelling "\\\n",
consistent with our handling for other similar cases -- an escaped newline is
always part of the token containing the next character, if any.
For the pattern "\\\n\n", this was somewhat more benign, but would produce an
extraneous whitespace token to clients who care about preserving whitespace.
However, it turns out that our lexing for line comments was relying on this bug
due to an off-by-one error in its computation of the end of the comment, on the
slow path where the comment might contain escaped newlines.
[ubsan] Skip null checks if they are constant-folded away
The IR builder can constant-fold null checks if the pointer operand
points to a constant. If the "is-non-null" check is folded away to
"true", don't emit the null check + branch.
Testing: check-clang, check-ubsan.
This slightly reduces the amount of null checks we emit when compiling
X86ISelLowering.cpp. Here are the numbers from patched/unpatched clangs
based on r300371.
[ubsan] Skip null checks on pointers to the start of an alloca
Pointers to the start of an alloca are non-null, so we don't need to
emit runtime null checks for them.
Testing: check-clang, check-ubsan.
This significantly reduces the amount of null checks we emit when
compiling X86ISelLowering.cpp. Here are the numbers from patched /
unpatched clangs based on r300371.
Eric Fiselier [Mon, 17 Apr 2017 22:06:13 +0000 (22:06 +0000)]
[coroutines] Fix rebuilding of implicit and dependent coroutine statements.
Summary:
Certain implicitly generated coroutine statements, such as the calls to 'return_value()' or `return_void()` or `get_return_object_on_allocation_failure()`, cannot be built until the promise type is no longer dependent. This means they are not built until after the coroutine body statement has been transformed.
This patch fixes an issue where these statements would never be built for coroutine templates.
It also fixes a small issue where diagnostics about `get_return_object_on_allocation_failure()` were incorrectly suppressed.
Benjamin Kramer [Mon, 17 Apr 2017 20:57:40 +0000 (20:57 +0000)]
Revert "Address http://bugs.llvm.org/pr30994 so that a non-friend can properly replace a friend, and a visible friend can properly replace an invisible friend but not vice verse, and definitions are not replaced. This fixes the two FIXME in SemaTemplate/friend-template.cpp."
This reverts commit r300443. Breaks compiling libc++ with modules in
some configurations.
Address http://bugs.llvm.org/pr30994 so that a non-friend can properly replace a friend, and a visible friend can properly replace an invisible friend but not vice verse, and definitions are not replaced. This fixes the two FIXME in SemaTemplate/friend-template.cpp.
The code implements Richard Smith suggestion in comment 3 of the PR.
Eric Fiselier [Sun, 16 Apr 2017 09:19:59 +0000 (09:19 +0000)]
[coroutines] Fix building of new/delete expressions when get_return_object_on_allocation_failure() is present.
Summary:
This patch implements [dcl.fct.def.coroutine]p8:
> The unqualified-id get_return_object_on_allocation_failure is looked up in the scope of
> class P by class member access lookup (3.4.5). If a declaration is found, ..., and if a
> global allocation function is selected, the ::operator new(size_t, nothrow_t) form shall be used.
> [...]
> The allocation function used in this case must have a non-throwing noexcept-specification.
Eric Christopher [Sat, 15 Apr 2017 06:15:00 +0000 (06:15 +0000)]
When we turn on vsx it should also turn on altivec explicitly, same
with disabling it as well as disabling all vsx specific features when
turning off altivec.
Do not run tests for crash recovery if libstdc++ safe mode is enabled
If expensive checks are enabled, safe mode of libstdc++ is enabled too.
In this mode the library uses more complex data that allow additional
checks, for instance, a container may keep list of iterators that points
to it. If a code crashes it can leave these complex library objects in
inconsistent state. It occurs in a few tests that check error recovery
if compiler crashes. These test hang in expensive check mode, as the
library tries to synchronize access to the iterators pointing to some
container, but corresponding mutex remains locked after the crash.
This fix marks these tests as unsupported if clang is built with
libstdc++ safe mode enabled.
The modules side of r299226, which serializes #pragma pack state,
doesn't work well.
The main purpose was to make -include and -include-pch match semantics
(the PCH side). We also started serializing #pragma pack in PCMs, in
the hopes of making modules and non-modules builds more consistent. But
consider:
As of r299226, the #pragma pack(show) gives "2", even though we've only
included "a.h".
- With -fmodules-local-submodule-visibility, this is clearly wrong. We
should get the default state (8 on x86_64).
- Without -fmodules-local-submodule-visibility, this kind of matches how
other things work (as if include-the-whole-module), but it's still
really terrible, and it doesn't actually make modules and non-modules
builds more consistent.
This commit disables the serialization for modules, essentially a
partial revert of r299226.
Going forward:
1. Having this #pragma pack stuff escape is terrible design (or, more
often, a horrible bug). We should prioritize adding warnings (maybe
-Werror by default?).
2. If we eventually reintroduce this for modules, it should only apply
to -fmodules-local-submodule-visibility, and it should be tracked on
a per-submodule basis.
[ubsan] Don't check alignment if the alignment is 1
If a pointer is 1-byte aligned, there's no use in checking its
alignment. Somewhat surprisingly, ubsan can spend a significant amount
of time doing just that!
This loosely depends on D30283.
Testing: check-clang, check-ubsan, and a stage2 ubsan build.
[ubsan] Reduce alignment checking of C++ object pointers
This patch teaches ubsan to insert an alignment check for the 'this'
pointer at the start of each method/lambda. This allows clang to emit
significantly fewer alignment checks overall, because if 'this' is
aligned, so are its fields.
This is essentially the same thing r295515 does, but for the alignment
check instead of the null check. One difference is that we keep the
alignment checks on member expressions where the base is a DeclRefExpr.
There's an opportunity to diagnose unaligned accesses in this situation
(as pointed out by Eli, see PR32630).
Testing: check-clang, check-ubsan, and a stage2 ubsan build.
Along with the patch from D30285, this roughly halves the amount of
alignment checks we emit when compiling X86FastISel.cpp. Here are the
numbers from patched/unpatched clangs based on r298160.
Kuba Mracek [Fri, 14 Apr 2017 16:53:25 +0000 (16:53 +0000)]
[ObjC] Fix lifetime markers of loop variable in EmitObjCForCollectionStmt [take 2]
CodeGenFunction::EmitObjCForCollectionStmt currently emits lifetime markers for the loop variable in an inconsistent way: lifetime.start is emitted before the loop is entered, but lifetime.end is emitted inside the loop. AddressSanitizer uses these markers to track out-of-scope accesses to local variables, and we get false positives in Obj-C foreach loops (in the 2nd iteration of the loop). This patch keeps the loop variable alive for the whole loop by extending ForScope and registering the cleanup function inside EmitAutoVarAlloca.
Erich Keane [Fri, 14 Apr 2017 15:21:18 +0000 (15:21 +0000)]
Make Gentoo GNU GCC Config override whitespace tolerant
The config-*triple* file handling isn't tolerant of
leading/trailing whitespace, making it not terribly
obvious when a single extraneous tab/space/etc will
cause the override to be ignored. This patch simply
trims the lines to ensure that it is tolerant of
whitespace.
Simon Pilgrim [Fri, 14 Apr 2017 15:05:57 +0000 (15:05 +0000)]
[X86][SSE] Update MOVNTDQA non-temporal loads to generic implementation (clang)
MOVNTDQA non-temporal aligned vector loads can be correctly represented using generic builtin loads, allowing us to remove the existing x86 intrinsics.
[docs] UBSan: Mention that print_stacktrace=1 is unsupported on Darwin
Printing out stack traces along with UBSan diagnostics is unsupported on
Darwin. That's because it isn't possible to use the fast unwinder or the
slow unwinder.
Apparently, it's inappropriate to use the fast unwinder for UBSan
issues. I'm not exactly sure why (see the comment in ubsan_diag.cc).
Forcing use of the fast unwinder produces decent results, AFAICT.
Darwin also does not appear to have a slow unwinder suitable for use
with the sanitizers. Apparently that's because of PR20800 [1][2]. But
that bug has been fixed. I'm not sure if there is anything preventing
use of the slow unwinder now.
Currently, passing UBSAN_OPTIONS=print_stacktrace=1 does nothing on
Darwin. This isn't good, but it might be a while before we can fix the
situation, so we should at least document it.
[1] https://github.com/google/sanitizers/issues/137
"We can't use the slow unwinder on OSX now, because Clang produces
incorrect unwind info for the ASan runtime functions on OSX
(http://llvm.org/PR20800)."
[2] https://bugs.llvm.org/show_bug.cgi?id=20800
Bug 20800 - Invalid compact unwind info generated for a function without
frame pointers on OSX
Kuba Mracek [Fri, 14 Apr 2017 00:32:43 +0000 (00:32 +0000)]
[ObjC] Fix lifetime markers of loop variable in EmitObjCForCollectionStmt
CodeGenFunction::EmitObjCForCollectionStmt currently emits lifetime markers for the loop variable in an inconsistent way: lifetime.start is emitted before the loop is entered, but lifetime.end is emitted inside the loop. AddressSanitizer uses these markers to track out-of-scope accesses to local variables, and we get false positives in Obj-C foreach loops (in the 2nd iteration of the loop). The markers of the loop variable need to be either both inside the loop (so that we poison and unpoison the variable in each iteration), or both outside. This patch implements the "both inside" approach.
Richard Smith [Thu, 13 Apr 2017 21:37:24 +0000 (21:37 +0000)]
PR32185: Revert r291512 and add a testcase for PR32185.
This reverts an attempt to check that types match when matching a
dependently-typed non-type template parameter. (This comes up when matching the
parameters of a template template parameter against the parameters of a
template template argument.)
The matching rules here are murky at best. Our behavior after this revert is
definitely wrong for certain C++17 features (for 'auto' template parameter
types within the parameter list of a template template argument in particular),
but our behavior before this revert is wrong for some pre-existing testcases,
so reverting to our prior behavior seems like our best option.
Hans Wennborg [Thu, 13 Apr 2017 17:42:45 +0000 (17:42 +0000)]
Warning-free clang-format plugin install for VS 15.0
With the new release of VS, it's required that all plugins migrate to
the new VSIX manifest format. The new format is backwards compatible
with all versions newer that Visual Studio 2012, so this migration
effectively drops support for older versions of the IDE.
It's also required that these new extensions are built with Visual
Studio 2017, so unfortunately it was necessary to migrate the project
and solution. Also removed COM references to EnvDTE and
Microsoft.VisualStudio.TextManager.Interop from the csproj, as they seem
to both be unnecessary and would trigger build warnings because of
changes to GAC.