Michael Wu [Fri, 3 Aug 2018 04:21:25 +0000 (04:21 +0000)]
[libclang 3/8] Add support for AttributedType
Summary:
This patch adds support to the libclang API for identifying AttributedTypes in CXTypes and reading the modified type that the type points to. Currently AttributedTypes are skipped. This patch continues to skip AttributedTypes by default, but adds a parsing option to CXTranslationUnit to include AttributedTypes.
This patch depends on D49066 since it also adds a CXType.
Testing will be added in another patch which depends on this one.
Yaxun Liu [Fri, 3 Aug 2018 03:18:56 +0000 (03:18 +0000)]
Sema: Fix explicit address space cast involving void pointers
Explicit cast of a void pointer to a pointer type in different address space is
incorrectly classified as bitcast, which causes invalid bitcast in codegen.
The patch fixes that by checking the address space of the source and destination
type and set the correct cast kind.
Michael Wu [Fri, 3 Aug 2018 03:03:20 +0000 (03:03 +0000)]
[libclang 1/8] Add support for ObjCObjectType
Summary: This patch adds support to the clang-c API for identifying ObjCObjects in CXTypes, enumerating type args and protocols on ObjCObjectTypes, and retrieving the base type of ObjCObjectTypes. Currently only ObjCInterfaceTypes are exposed, which do not have type args or protocols.
Michael Kruse [Fri, 3 Aug 2018 01:21:16 +0000 (01:21 +0000)]
Append new attributes to the end of an AttributeList.
Recommit of r335084 after revert in r335516.
... instead of prepending it at the beginning (the original behavior
since implemented in r122535 2010-12-23). This builds up an
AttributeList in the the order in which the attributes appear in the
source.
The reverse order caused nodes for attributes in the AST (e.g. LoopHint)
to be in the reverse order, and therefore printed in the wrong order in
-ast-dump. Some TODO comments mention this. The order was explicitly
reversed for enable_if attribute overload resolution and name mangling,
which is not necessary anymore with this patch.
The change unfortunately has some secondary effect, especially on
diagnostic output. In the simplest cases, the CHECK lines or expected
diagnostic were changed to the the new output. If the kind of
error/warning changed, the attributes' order was changed instead.
This unfortunately causes some 'previous occurrence here' hints to be
textually after the main marker. This typically happens when attributes
are merged, but are incompatible to each other. Interchanging the role
of the the main and note SourceLocation will also cause the case where
two different declaration's attributes (in contrast to multiple
attributes of the same declaration) are merged to be reverse. There is
no easy fix because sometimes previous attributes are merged into a new
declaration's attribute list, sometimes new attributes are added to a
previous declaration's attribute list. Since 'previous occurrence here'
pointing to locations after the main marker is not rare, I left the
markers as-is; it is only relevant when the attributes are declared in
the same declaration anyway.
Richard Smith [Fri, 3 Aug 2018 01:00:01 +0000 (01:00 +0000)]
[modules] Defer merging deduced return types.
We can't read a deduced return type until we are sure that the types referred
to by it are not in the middle of being loaded. So defer all reading of such
deduced return types until the end of the recursive deserialization step.
Also, when we load a function type that has a deduced return type, update all
other redeclarations of the function to have that deduced return type.
Reka Kovacs [Thu, 2 Aug 2018 23:02:08 +0000 (23:02 +0000)]
[analyzer] Detect pointers escaped after ReturnStmt execution in MallocChecker.
Objects local to a function are destroyed right after the statement returning
(part of) them is executed in the analyzer. This patch enables MallocChecker to
warn in these cases.
Reka Kovacs [Thu, 2 Aug 2018 22:31:03 +0000 (22:31 +0000)]
[analyzer] Obtain a ReturnStmt from a CFGAutomaticObjDtor.
The CoreEngine only gives us a ReturnStmt if the last element in the
CFGBlock is a CFGStmt, otherwise the ReturnStmt is nullptr.
This patch adds support for the case when the last element is a
CFGAutomaticObjDtor, by returning its TriggerStmt as a ReturnStmt.
JF Bastien [Thu, 2 Aug 2018 17:35:46 +0000 (17:35 +0000)]
__c11_atomic_load's _Atomic can be const
Summary:
C++11 onwards specs the non-member functions atomic_load and atomic_load_explicit as taking the atomic<T> by const (potentially volatile) pointer. C11, in its infinite wisdom, decided to drop the const, and C17 will fix this with DR459 (the current draft forgot to fix B.16, but that’s not the normative part).
clang’s lib/Headers/stdatomic.h implements these as #define to the __c11_* equivalent, which are builtins with custom typecheck. Fix the typecheck.
Matt Arsenault [Thu, 2 Aug 2018 12:14:28 +0000 (12:14 +0000)]
Try to make builtin address space declarations not useless
The way address space declarations for builtins currently work
is nearly useless. The code assumes the address spaces used for
builtins is a confusingly named "target address space" from user
code using __attribute__((address_space(N))) that matches
the builtin declaration. There's no way to use this to declare
a builtin that returns a language specific address space.
The terminology used is highly cofusing since it has nothing
to do with the the address space selected by the target to use
for a language address space.
This feature is essentially unused as-is. AMDGPU and NVPTX
are the only in-tree targets attempting to use this. The AMDGPU
builtins certainly do not behave as intended (i.e. all of the
builtins returning pointers can never compile because the numbered
address space never matches the expected named address space).
The NVPTX builtins are missing tests for some, and the others
seem to rely on an implicit addrspacecast.
Change the used address space for builtins based on a target
hook to allow using a language address space for a builtin.
This allows the same builtin declaration to be used for multiple
languages with similarly purposed address spaces (e.g. the same
AMDGPU builtin can be used in OpenCL and CUDA even though the
constant address spaces are arbitarily different).
This breaks the possibility of using arbitrary numbered
address spaces alongside the named address spaces for builtins.
If this is an issue we probably need to introduce another builtin
declaration character to distinguish language address spaces from
so-called "target address spaces".
Martin Probst [Thu, 2 Aug 2018 11:52:08 +0000 (11:52 +0000)]
clang-format: fix a crash in comment wraps.
Summary:
Previously, clang-format would crash if it tried to wrap an overlong
single line comment, because two parts of the code inserted a break in
the same location.
/** heregoesalongcommentwithnospace */
This wasn't previously noticed as it could only trigger for an overlong
single line comment that did have no breaking opportunities except for a
whitespace at the very beginning.
This also introduces a check for JavaScript to not ever wrap a comment
before an opening curly brace:
/** @mods {donotbreakbeforethecurly} */
This is because some machinery parsing these tags sometimes supports
breaks before a possible `{`, but in some other cases does not.
Previously clang-format was careful never to wrap a line with certain
tags on it. The better solution is to specifically disable wrapping
before the problematic token: this allows wrapping and aligning comments
but still avoids the problem.
Erich Keane [Wed, 1 Aug 2018 20:48:16 +0000 (20:48 +0000)]
[AST][1/4] Move the bit-fields from TagDecl, EnumDecl and RecordDecl into DeclContext
DeclContext has a little less than 8 bytes free due to the alignment
requirements on 64 bits archs. This set of patches moves the
bit-fields from classes deriving from DeclContext into DeclContext.
On 32 bits archs this increases the size of DeclContext by 4 bytes
but this is balanced by an equal or larger reduction in the size
of the classes deriving from it.
On 64 bits archs the size of DeclContext stays the same but
most of the classes deriving from it shrink by 8/16 bytes.
(-print-stats diff here https://reviews.llvm.org/D49728)
When doing an -fsyntax-only on all of Boost this result
in a 3.6% reduction in the size of all Decls and
a 1% reduction in the run time due to the lower cache
miss rate.
For now CXXRecordDecl is not touched but there is
an easy 6 (if I count correctly) bytes gain available there
by moving some bits from DefinitionData into the free
space of DeclContext. This will be the subject of another patch.
This patch sequence also enable the possibility of refactoring
FunctionDecl: To save space some bits from classes deriving from
FunctionDecl were moved to FunctionDecl. This resulted in a
lot of stuff in FunctionDecl which do not belong logically to it.
After this set of patches however it is just a simple matter of
adding a SomethingDeclBitfields in DeclContext and moving the
bits to it from FunctionDecl.
This first patch introduces the anonymous union in DeclContext
and all the *DeclBitfields classes holding the bit-fields, and moves
the bits from TagDecl, EnumDecl and RecordDecl into DeclContext.
This patch is followed by https://reviews.llvm.org/D49732,
https://reviews.llvm.org/D49733 and https://reviews.llvm.org/D49734.
Michal Gorny [Wed, 1 Aug 2018 20:38:22 +0000 (20:38 +0000)]
[test] Fix %hmaptool path for standalone builds
Fix %hmaptool path to refer to clang_tools_dir instead of
llvm_tools_dir, in order to fix standalone builds. The tool is built
as part of clang, so it won't be found in installed LLVM tools.
Hans Wennborg [Wed, 1 Aug 2018 17:51:23 +0000 (17:51 +0000)]
Revert r338455 "[constexpr] Support for constant evaluation of __builtin_memcpy and __builtin_memmove (in non-type-punning cases)."
It caused asserts during Chromium builds, see reply on the cfe-commits thread.
> This is intended to permit libc++ to make std::copy etc constexpr
> without sacrificing the optimization that uses memcpy on
> trivially-copyable types.
>
> __builtin_strcpy and __builtin_wcscpy are not handled by this change.
> They'd be straightforward to add, but we haven't encountered a need for
> them just yet.
Ilya Biryukov [Wed, 1 Aug 2018 15:32:56 +0000 (15:32 +0000)]
[Format] Fix for bug 35641
Summary:
Bug was caused due to comments at the start of scope. For a code like:
```
int func() { //
int b;
int c;
}
```
the comment at the first line gets IndentAndNestingLevel (1,1) whereas
the following declarations get only (0,1) which prevents them from insertion
of a new scope. So, I changed the AlignTokenSequence to look at previous
*non-comment* token when deciding whether to introduce a new scope into
stack or not.
David Green [Wed, 1 Aug 2018 14:36:12 +0000 (14:36 +0000)]
[UnrollAndJam] Add unroll_and_jam pragma handling
This adds support for the unroll_and_jam pragma, to go with the recently
added unroll and jam pass. The name of the pragma is the same as is used
in the Intel compiler, and most of the code works the same as for unroll.
#pragma clang loop unroll_and_jam has been separated into a different
patch. This part adds #pragma unroll_and_jam with an optional count, and
#pragma no_unroll_and_jam to disable the transform.
Yuka Takahashi [Wed, 1 Aug 2018 09:50:02 +0000 (09:50 +0000)]
[Modules] Do not emit relocation error when -fno-validate-pch is set
Summary:
Clang emits error when implicit modules was relocated from the
first build directory. However this was biting our usecase where we copy
the contents of build directory to another directory in order to
distribute.
Roman Lebedev [Wed, 1 Aug 2018 06:06:16 +0000 (06:06 +0000)]
[AST] CastExpr: BasePathSize is not large enough.
Summary:
rC337815 / D49508 had to cannibalize one bit of `CastExprBitfields::BasePathSize` in order to squeeze `PartOfExplicitCast` boolean.
That reduced the maximal value of `PartOfExplicitCast` from 9 bits (~512) down to 8 bits (~256).
Apparently, that mattered. Too bad there weren't any tests.
It caused [[ https://bugs.llvm.org/show_bug.cgi?id=38356 | PR38356 ]].
So we need to increase `PartOfExplicitCast` back at least to 9 bits, or a bit more.
For obvious reasons, we can't do that in `CastExprBitfields` - that would blow up the size of every `Expr`.
So we need to either just add a variable into the `CastExpr` (as done here),
or use `llvm::TrailingObjects`. The latter does not seem to be straight-forward.
Perhaps, that needs to be done not for the `CastExpr` itself, but for all of it's `final` children.
Reviewers: rjmccall, rsmith, erichkeane
Reviewed By: rjmccall
Subscribers: bricci, hans, cfe-commits, waddlesplash
Petr Hosek [Wed, 1 Aug 2018 03:30:06 +0000 (03:30 +0000)]
[OpenEmbedded] Explicitly specify -rtlib in tests
Tests added in r338294 implicitly assume that libgcc is the runtime library,
but that's not the case when the user configures Clang to use compiler-rt in
which case these tests will break. Explicitly request libgcc when invoking
clang in these tests to avoid that.
Artem Dergachev [Wed, 1 Aug 2018 01:58:15 +0000 (01:58 +0000)]
[analyzer] CallEvent: Add helper methods for obtaining the callee stack frame.
Newly added methods allow reasoning about the stack frame of the call (as
opposed to the stack frame on which the call was made, which was always
available) - obtain the stack frame context, obtain parameter regions - even if
the call is not going to be (or was not) inlined, i.e. even if the analysis
has never actually entered the stack frame.
Richard Smith [Wed, 1 Aug 2018 00:33:25 +0000 (00:33 +0000)]
[P0936R0] add [[clang::lifetimebound]] attribute
This patch adds support for a new attribute, [[clang::lifetimebound]], that
indicates that the lifetime of a function result is related to one of the
function arguments. When walking an initializer to make sure that the lifetime
of the initial value is at least as long as the lifetime of the initialized
object, we step through parameters (including the implicit object parameter of
a non-static member function) that are marked with this attribute.
There's nowhere to write an attribute on the implicit object parameter, so in
lieu of that, it may be applied to a function type (where it appears
immediately after the cv-qualifiers and ref-qualifier, which is as close to a
declaration of the implicit object parameter as we have). I'm currently
modeling this in the AST as the attribute appertaining to the function type.
Richard Smith [Tue, 31 Jul 2018 23:35:09 +0000 (23:35 +0000)]
[constexpr] Support for constant evaluation of __builtin_memcpy and
__builtin_memmove (in non-type-punning cases).
This is intended to permit libc++ to make std::copy etc constexpr
without sacrificing the optimization that uses memcpy on
trivially-copyable types.
__builtin_strcpy and __builtin_wcscpy are not handled by this change.
They'd be straightforward to add, but we haven't encountered a need for
them just yet.
Revert r337635 "[Driver] Sanitizer support based on runtime library presence"
This change causes issues with distributed build systems, which may only
have compiler binaries without any runtime libraries. See discussion
about this on https://reviews.llvm.org/D15225.
Richard Smith [Tue, 31 Jul 2018 21:01:53 +0000 (21:01 +0000)]
[serialization] PR34728: Don't assume that only a suffix of template
parameters can have default arguments.
At least for function templates and class template partial
specializations, it's possible for a template parameter with a default
argument to be followed by a non-pack template parameter with no default
argument, and this case was not properly handled here.
[CFG] [analyzer] Implement function argument construction contexts.
In r330377 and r338425 we have already identified what constitutes function
argument constructors and added stubs in order to prevent confusing them
with other temporary object constructors.
Now we implement a ConstructionContext sub-class to carry all the necessary
information about the construction site, namely call expression and argument
index.
On the analyzer side, the patch interacts with the recently implemented
pre-C++17 copy elision support in an interesting manner. If on the CFG side we
didn't find a construction context for the elidable constructor, we build
the CFG as if the elidable constructor is not elided, and the non-elided
constructor within it is a simple temporary. But the same problem may occur
in the analyzer: if the elidable constructor has a construction context but
the analyzer doesn't implement such context yet, the analyzer should also
try to skip copy elision and still inline the non-elided temporary constructor.
This was implemented by adding a "roll back" mechanism: when elision fails,
roll back the changes and proceed as if it's a simple temporary. The approach
is wonky, but i'm fine with that as long as it's merely a defensive mechanism
that should eventually go away once all construction contexts become supported.
[OpenCL] Forbid size dependent types used as kernel arguments
Summary:
Size_t, intptr_t, uintptr_t and ptrdiff_t cannot be used as kernel
arguments, according to OpenCL Specification s6.9k:
The size in bytes of these types are implementation-defined and in
addition can also be different for the OpenCL device and the host
processor making it difficult to allocate buffer objects to be passed
as arguments to a kernel declared as pointer to these types.
[CFG] [analyzer] Add stubs for constructor and message argument constructors.
CFG now correctly identifies construction context for temporaries constructed
for the purpose of passing into a function as an argument.
Such context is still not fully implemented because the information it provides
is not rich enough: it doens't contain information about argument index.
It will be addresssed later.
This patch is an extension of r330377 to C++ construct-expressions and
Objective-C message expressions which aren't call-expressions but require
similar handling. C++ new-expressions with placement arguments still remain to
be handled.
[analyzer] Don't try to simplify mixed Loc/NonLoc expressions.
This fix is similar to r337769 and addresses a regression caused by r337167.
When an operation between a nonloc::LocAsInteger and a non-pointer symbol
is performed, the LocAsInteger-specific part of information is lost.
When the non-pointer symbol is collapsing into a constant, we cannot easily
re-evaluate the result, because we need to recover the missing
LocAsInteger-specific information (eg., integer type, or the very fact that
this pointer was at some point converted to an integer).
Add one more defensive check to prevent crashes on trying to simplify a
SymSymExpr with different Loc-ness of operands.
[OPENMP] Change linkage of offloading symbols to support dropping
offload targets.
Changed the linkage of omp_offloading.img_start.<triple> and omp_offloading.img_end.<triple> symbols from external to external weak to allow dropping of some targets during linking.
[OPENMP] Prevent problems with linking of the static variables.
No need to change the linkage, we can avoid the problem using special variable. That points to the original variable and, thus, prevent some of the optimizations that might break the compilation.
David Bolvansky [Tue, 31 Jul 2018 14:21:46 +0000 (14:21 +0000)]
[RISCV] Add driver for riscv32-unknown-elf baremetal target
Summary:
This patch adds a driver for the baremetal RISC-V target (i.e. riscv32-unknown-elf). For reference, D39963 added basic target info and added support for riscv32-linux-unknown-elf.
Aleksandr Urakov [Tue, 31 Jul 2018 08:27:06 +0000 (08:27 +0000)]
Improve support of PDB as an external layout source
Summary:
This patch improves support of PDB as an external layout source
in the next cases:
- Multiple non-virtual inheritance from packed base classes. When using
external layout, there's no need to align `NonVirtualSize` of a base class.
It may cause an overlapping when the next base classes will be layouted
(but there is a slightly different case in the test because I can't find
a way to specify a base offset);
- Support of nameless structs and unions. There is no info about nameless child
structs and unions in Microsoft cl-emitted PDBs. Instead all its fields
are just treated as outer structure's (union's) fields. This also causes
a fields overlapping, and makes it possible for unions to have fields located
at a non-zero offset.
Yes, i erroneously assumed that the "after" was meant,
but i was wrong:
> I really meant "performed before", for cases like 4u / -2,
> where -2 is implicitly converted to UINT_MAX - 2 before
> the computation. Conversions that are performed after
> a computation aren't part of the computation at all,
> so I think it's much clearer that they're not in scope
> for this sanitizer.
David Greene [Mon, 30 Jul 2018 19:08:20 +0000 (19:08 +0000)]
Make test/Driver/baremetal.cpp work with linkers other than lld
This test fails if clang is configure with, for example, gold as the
default linker. It does not appear that this test really relies on lld
so make the checks accept ld, ld.gold and ld.bfd too.
Roman Lebedev [Mon, 30 Jul 2018 18:58:30 +0000 (18:58 +0000)]
[clang][ubsan] Implicit Conversion Sanitizer - integer truncation - clang part
Summary:
C and C++ are interesting languages. They are statically typed, but weakly.
The implicit conversions are allowed. This is nice, allows to write code
while balancing between getting drowned in everything being convertible,
and nothing being convertible. As usual, this comes with a price:
```
unsigned char store = 0;
bool consume(unsigned int val);
void test(unsigned long val) {
if (consume(val)) {
// the 'val' is `unsigned long`, but `consume()` takes `unsigned int`.
// If their bit widths are different on this platform, the implicit
// truncation happens. And if that `unsigned long` had a value bigger
// than UINT_MAX, then you may or may not have a bug.
// Similarly, integer addition happens on `int`s, so `store` will
// be promoted to an `int`, the sum calculated (0+768=768),
// and the result demoted to `unsigned char`, and stored to `store`.
// In this case, the `store` will still be 0. Again, not always intended.
store = store + 768; // before addition, 'store' was promoted to int.
}
// But yes, sometimes this is intentional.
// You can either make the conversion explicit
(void)consume((unsigned int)val);
// or mask the value so no bits will be *implicitly* lost.
(void)consume((~((unsigned int)0)) & val);
}
```
Yes, there is a `-Wconversion`` diagnostic group, but first, it is kinda
noisy, since it warns on everything (unlike sanitizers, warning on an
actual issues), and second, there are cases where it does **not** warn.
So a Sanitizer is needed. I don't have any motivational numbers, but i know
i had this kind of problem 10-20 times, and it was never easy to track down.
The logic to detect whether an truncation has happened is pretty simple
if you think about it - https://godbolt.org/g/NEzXbb - basically, just
extend (using the new, not original!, signedness) the 'truncated' value
back to it's original width, and equality-compare it with the original value.
The most non-trivial thing here is the logic to detect whether this
`ImplicitCastExpr` AST node is **actually** an implicit conversion, //or//
part of an explicit cast. Because the explicit casts are modeled as an outer
`ExplicitCastExpr` with some `ImplicitCastExpr`'s as **direct** children.
https://godbolt.org/g/eE1GkJ
Nowadays, we can just use the new `part_of_explicit_cast` flag, which is set
on all the implicitly-added `ImplicitCastExpr`'s of an `ExplicitCastExpr`.
So if that flag is **not** set, then it is an actual implicit conversion.
As you may have noted, this isn't just named `-fsanitize=implicit-integer-truncation`.
There are potentially some more implicit conversions to be warned about.
Namely, implicit conversions that result in sign change; implicit conversion
between different floating point types, or between fp and an integer,
when again, that conversion is lossy.
One thing i know isn't handled is bitfields.
This is a clang part.
The compiler-rt part is D48959.