Ensure that we define the `_Unwind_Control_Block` structure used on ARM
EHABI targets. This is needed for building libc++abi with the unwind.h
from the resource dir. A minor fallout of this is that we needed to
create a typedef for _Unwind_Exception to work across ARM EHABI and
non-EHABI targets. The structure definitions here are based originally
on the documentation from ARM under the "Exception Handling ABI for the
ARM® Architecture" Section 7.2. They are then adjusted to more closely
reflect the definition in libunwind from LLVM. Those changes are
compatible in layout but permit easier use in libc++abi and help
maintain compatibility between libunwind and the compiler provided
definition.
Richard Smith [Wed, 26 Jul 2017 22:01:09 +0000 (22:01 +0000)]
Add branch weights to branches for static initializers.
The initializer for a static local variable cannot be hot, because it runs at
most once per program. That's not quite the same thing as having a low branch
probability, but under the assumption that the function is invoked many times,
modeling this as a branch probability seems reasonable.
For TLS variables, the situation is less clear, since the initialization side
of the branch can run multiple times in a program execution, but we still
expect initialization to be rare relative to non-initialization uses. It would
seem worthwhile to add a PGO counter along this path to make this estimation
more accurate in future.
For globals with guarded initialization, we don't yet apply any branch weights.
Due to our use of COMDATs, the guard will be reached exactly once per DSO, but
we have no idea how many DSOs will define the variable.
Hans Wennborg [Wed, 26 Jul 2017 21:29:24 +0000 (21:29 +0000)]
Revert r309106 "Recommit r308327 2nd time: Add a warning for missing"
The warning fires on non-suspicious code in Chromium. Reverting until a
solution is figured out.
> Recommit r308327 2nd time: Add a warning for missing
> '#pragma pack (pop)' and suspicious uses of '#pragma pack' in included files
>
> The first recommit (r308441) caused a "non-default #pragma pack value might
> change the alignment of struct or union members in the included file" warning
> in LLVM itself. This recommit tweaks the added warning to avoid warnings for
> #includes that don't have any records that are affected by the non-default
> alignment. This tweak avoids the previously emitted warning in LLVM.
>
> Original message:
>
> This commit adds a new -Wpragma-pack warning. It warns in the following cases:
>
> - When a translation unit is missing terminating #pragma pack (pop) directives.
> - When entering an included file if the current alignment value as determined
> by '#pragma pack' directives is different from the default alignment value.
> - When leaving an included file that changed the state of the current alignment
> value.
>
> rdar://10184173
>
> Differential Revision: https://reviews.llvm.org/D35484
[Bash-autocompletion] Show HelpText with possible flags
Summary:
`clang --autocomplete=-std` will show
```
-std: Language standard to compile for
-std= Language standard to compile for
-stdlib= C++ standard library to use
```
after this change.
However, showing HelpText with completion in bash seems super tricky, so
this feature will be used in other shells (fish, zsh...).
Alex Lorenz [Wed, 26 Jul 2017 12:20:57 +0000 (12:20 +0000)]
Recommit r308327 2nd time: Add a warning for missing
'#pragma pack (pop)' and suspicious uses of '#pragma pack' in included files
The first recommit (r308441) caused a "non-default #pragma pack value might
change the alignment of struct or union members in the included file" warning
in LLVM itself. This recommit tweaks the added warning to avoid warnings for
#includes that don't have any records that are affected by the non-default
alignment. This tweak avoids the previously emitted warning in LLVM.
Original message:
This commit adds a new -Wpragma-pack warning. It warns in the following cases:
- When a translation unit is missing terminating #pragma pack (pop) directives.
- When entering an included file if the current alignment value as determined
by '#pragma pack' directives is different from the default alignment value.
- When leaving an included file that changed the state of the current alignment
value.
David Majnemer [Tue, 25 Jul 2017 23:33:58 +0000 (23:33 +0000)]
[CodeGen] Correctly model std::byte's aliasing properties
std::byte, when defined as an enum, needs to be given special treatment
with regards to its aliasing properties. An array of std::byte is
allowed to be used as storage for other types.
[ubsan] Null-check pointers in -fsanitize=vptr (PR33881)
The instrumentation generated by -fsanitize=vptr does not null check a
user pointer before loading from it. This causes crashes in the face of
UB member calls (this=nullptr), i.e it's causing user programs to crash
only after UBSan is turned on.
The fix is to make run-time null checking a prerequisite for enabling
-fsanitize=vptr, and to then teach UBSan to reuse these run-time null
checks to make -fsanitize=vptr safe.
Testing: check-clang, check-ubsan, a stage2 ubsan-enabled build
Peter Szecsi [Tue, 25 Jul 2017 19:23:23 +0000 (19:23 +0000)]
[StaticAnalyzer] Completely unrolling specific loops with known bound option
This feature allows the analyzer to consider loops to completely unroll.
New requirements/rules (for unrolling) can be added easily via ASTMatchers.
Right now it is hidden behind a flag, the aim is to find the correct heuristic
and create a solution which results higher coverage % and more precise
analysis, thus can be enabled by default.
Right now the blocks which belong to an unrolled loop are marked by the
LoopVisitor which adds them to the ProgramState.
Then whenever we encounter a CFGBlock in the processCFGBlockEntrance which is
marked then we skip its investigating. That means, it won't be considered to
be visited more than the maximal bound for visiting since it won't be checked.
Introduce -nostdlib++ flag to disable linking the C++ standard library.
Projects that want to statically link their own C++ standard library currently
need to pass -nostdlib or -nodefaultlibs, which also disables linking of the
builtins library, -lm, and so on. Alternatively, they could use `clang` instead
of `clang++`, but that already disables implicit addition of -lm on some
toolchains.
Add a dedicated flag -nostdlib++ that disables just linking of libc++ /
libstdc++. This is analogous to -nostdinc++.
[analyzer] Add diagnostic text for generalized refcount annotations.
Add a 'Generalized' object kind to the retain-count checker and suitable
generic diagnostic text for retain-count diagnostics involving those objects.
For now the object kind is introduced in summaries by 'annotate' attributes.
Once we have more experience with these annotations we will propose explicit
attributes.
This test case is causing all PPC and SystemZ bots to remain red.
Notifying the author via Diffusion did not yield any answer. Therefore, I'm
adding the missing triple. I have no idea if this is the intended triple, but
it seems to fit the bill and should turn the bots back to green.
If the intended triple is a different one, please feel free to change it but I
need make this change to turn the bots back to green now.
Manuel Klimek [Tue, 25 Jul 2017 10:22:06 +0000 (10:22 +0000)]
Fix incorrect use of current directory to find moved paths in ASTReader.
CurrentDir was set as the path of the current module, but that can change as
part of a chain of loaded modules.
When we try to locate a file mentioned in a module that does not exist, we use
a heuristic to look at the relative path between the original location of the
module and the file we look for, and use that relatively to the CurrentDir.
This only works if CurrentDir is the same as the (current) path of the module
file the file was mentioned in; if it is not, we look at the path relatively to
the wrong directory, and can end up reading random unrelated files that happen
to have the same name.
This patch fixes this by using the BaseDirectory of the module file the file
we look for was mentioned in instead of the CurrentDir heuristic.
[analyzer] Treat throws as sinks for suppress-on-sink purposes.
Because since r308957 the suppress-on-sink feature contains its own
mini-analysis, it also needs to become aware that C++ unhandled exceptions
cause sinks. Unfortunately, for now we treat all exceptions as unhandled in
the analyzer, so suppress-on-sink needs to do the same.
[analyzer] Further improve suppress-on-sink behavior in incomplete analyses.
If a certain memory leak (or other similar bug) found by the analyzer is known
to be happening only before abnormal termination of the program ("sink", eg.
assertion failure in the code under analysis, or another bug that introduces
undefined behavior), such leak warning is discarded. However, if the analysis
has never reaches completion (due to complexity of the code), it may be
failing to notice the sink.
This commit further extends the partial solution introduced in r290341 to cover
cases when a complicated control flow occurs before encountering a no-return
statement (which anyway inevitably leads to such statement(s)) by traversing
the respective section of the CFG in a depth-first manner. A complete solution
still seems elusive.
[NFC] Use RAII to un-poison and then re-poison __VA_ARGS__
- This will also be used for the forthcoming __VA_OPT__ feature approved for C++2a.
- recommended by rsmith during his review of the __VA_OPT__ patch (https://reviews.llvm.org/D35782)
Adrian Prantl [Mon, 24 Jul 2017 23:48:51 +0000 (23:48 +0000)]
Debug Info: Avoid completing class types when a definition is in a module.
This patch adds an early exit to CGDebugInfo::completeClassData() when
compiling with -gmodules and the to-be-completed type is available in
a clang module.
Under Windows Itanium, we need to export virtual and non-virtual thunks
if the functions being thunked are exported. These thunks would
previously inherit their dllexport attribute from the declaration, but
r298330 changed declarations to not have dllexport attributes. We
therefore need to add the dllexport attribute to the definition
ourselves now. This is consistent with MinGW GCC's behavior.
This redoes r306770 but limits the logic to Itanium. MicrosoftCXXABI's
setThunkLinkage ensures that thunks aren't exported under that ABI, so
I'm handling this in ItaniumCXXABI's setThunkLinkage for symmetry.
We need to export these thunks because they can be referenced outside
the library they're defined in. For example, if a child class without a
key function inherits from a parent class with a key function, the
parent's thunks will only be defined in the library with the key
function, but the construction vtable for the parent in the child might
be emitted outside the library (since the child doesn't have a key
function), and it needs to reference the parent's thunks.
We don't need to mark these thunks as imported since any references to
them will occur in data, so the compiler can't generate the IAT load
sequence anyway. Instead, we rely on the linker generating import thunks
for the thunks.
C2017 update 3 produces a clang that crashes when compiling clang. Disabling
optimizations for StmtProfiler::VisitCXXOperatorCallExpr() makes the crash go
away.
Patch from Bruce Dawson <brucedawson@chromium.org>!
https://reviews.llvm.org/D35757
[clang-format] Fix comment levels between '} else {' and PPDirective.
Summary:
This fixes a regression exposed by r307795 and rL308725 in which the level of a
comment line between '} else {' and a preprocessor directive is incorrectly set
as the level of the '} else {' line. For example, this :
```
int f(int i) {
if (i) {
++i;
} else {
// comment
#ifdef A
--i;
#endif
}
}
```
was formatted as:
```
int f(int i) {
if (i) {
++i;
} else {
// comment
#ifdef A
--i;
#endif
}
}
```
[Modules] Rework r274270. Let Clang targets depend on intrinsics_gen.
This gets rid of almost LLVM targets unconditionally depending on intrinsic_gen.
Clang's modules still have weird dependencies and hard to remove intrinsics_gen in better way.
Then, it'd be better to give whole clang targets depend on intrinsic_gen.
Erich Keane [Fri, 21 Jul 2017 22:37:03 +0000 (22:37 +0000)]
Break up Targets.cpp into a header/impl pair per target type[NFCI]
Targets.cpp is getting unwieldy, and even minor changes cause the entire thing
to cause recompilation for everyone. This patch bites the bullet and breaks
it up into a number of files.
I tended to keep function definitions in the class declaration unless it
caused additional includes to be necessary. In those cases, I pulled it
over into the .cpp file. Content is copy/paste for the most part,
besides includes/format/etc.
Erich Keane [Fri, 21 Jul 2017 18:50:36 +0000 (18:50 +0000)]
Complex Long Double classification In RegCall calling convention
This change is part of the RegCall calling convention support for LLVM.
Existing RegCall implementation was extended to include correct handling of
Complex Long Double type. Complex long double types should be returned/passed
in memory and not register stack. This patch implements this behavior.
Alex Lorenz [Fri, 21 Jul 2017 12:49:28 +0000 (12:49 +0000)]
[clang-diff] Add initial implementation
This is the first commit for the "Clang-based C/C++ diff tool" GSoC project.
ASTDiff is a new library that computes a structural AST diff between two ASTs
using the gumtree algorithm. Clang-diff is a new Clang tool that will show
the structural code changes between different ASTs.
[clang-format] Fix comment levels between '}' and PPDirective
Summary:
This fixes a regression exposed by r307795 in which the level of a comment line
between '}' and a preprocessor directive is incorrectly set as the level of the
line before the '}'. In effect, this:
```
int f(int i) {
int j = i;
return i + j;
}
// comment
#ifdef A
#endif
```
was formatted as:
```
int f(int i) {
int j = i;
return i + j;
}
// comment
Simon Atanasyan [Fri, 21 Jul 2017 08:10:57 +0000 (08:10 +0000)]
[mips] Add `short_call` to the set of `long_call/far/near` attributes
MIPS gcc supports `long_call/far/near` attributes only, but other
targets have the `short_call` attribut, so let's support it for MIPS
for consistency.
Richard Trieu [Fri, 21 Jul 2017 04:56:48 +0000 (04:56 +0000)]
Fix tblgen error.
tblgen couldn't determing a unique name between "long_call" and "far", so it
errored out when generating documentation. Copy the documentation, and give
an explicit header for "long_call".
Petr Hosek [Fri, 21 Jul 2017 01:17:49 +0000 (01:17 +0000)]
[Driver] Consider -fno-sanitize=... state when filtering out -fsanitize-coverage=...
The driver ignores -fsanitize-coverage=... flags when also given
-fsanitize=... flags for sanitizer flavors that don't support the
coverage runtime. This logic failed to account for subsequent
-fno-sanitize=... flags that disable the sanitizer flavors that
conflict with -fsanitize-coverage=... flags.
The patch adds support of i128 params lowering. The changes are quite trivial to
support i128 as a "special case" of integer type. With this patch, we lower i128
params the same way as aggregates of size 16 bytes: .param .b8 _ [16].
Currently, NVPTX can't deal with the 128 bit integers:
* in some cases because of failed assertions like
ValVTs.size() == OutVals.size() && "Bad return value decomposition"
* in other cases emitting PTX with .i128 or .u128 types (which are not valid [1])
[1] http://docs.nvidia.com/cuda/parallel-thread-execution/index.html#fundamental-types
Simon Atanasyan [Thu, 20 Jul 2017 20:34:18 +0000 (20:34 +0000)]
[CodeGen][mips] Support `long_call/far/near` attributes
This patch adds support for the `long_call`, `far`, and `near` attributes
for MIPS targets. The `long_call` and `far` attributes are synonyms. All
these attributes override `-mlong-calls` / `-mno-long-calls` command
line options for particular function.
This diff addresses FIXMEs in lib/Analysis/ScanfFormatString.cpp
for the case of ssize_t format specifier and adds tests.
In particular, this change enables Clang to emit a warning
on incorrect using of "%zd"/"%zn".
Peter Szecsi [Wed, 19 Jul 2017 23:50:00 +0000 (23:50 +0000)]
This feature allows the analyzer to consider loops to completely unroll. New
requirements/rules (for unrolling) can be added easily via ASTMatchers.
The current implementation is hidden behind a flag.
Right now the blocks which belong to an unrolled loop are marked by the
LoopVisitor which adds them to the ProgramState. Then whenever we encounter a
CFGBlock in the processCFGBlockEntrance which is marked then we skip its
investigating. That means, it won't be considered to be visited more than the
maximal bound for visiting since it won't be checked.
projects / clang / log