Summary:
This provides a macro that expands to __builtin_debugtrap() for clang,
and __debugbreak() for MSVC.
It intentionally expands to nothing for compilers that do not support a
similar mechanism that halts the debugger without otherwise crashing the
process.
Differential Revision: http://reviews.llvm.org/D18002
llvm-svn: 263095
We have known UB in some ilists where we static cast half nodes to
(larger) derived types and use the address. See llvm.org/PR26753.
This needs to be fixed, but in the meantime it'd be nice if running
ubsan didn't complain. This adds annotations in the two places where
ubsan complains while running check-all of a sanitized clang build.
llvm-svn: 262683
Patch by Alexander Riccio
This patch enables `constexpr` on Visual Studio 2015 by adding `||
LLVM_MSC_PREREQ(1900)` to the preprocessor `#if` statement. Since VS2013
doesn't support `constexpr`, that's purposely excluded. The
`LLVM_CONSTEXPR` macro is used in ~25 places.
I also added the MSVC/SAL equivalent of:
- `__attribute__((__warn_unused_result__))` as an
`LLVM_ATTRIBUTE_UNUSED_RESULT` definition
- `__attribute__((returns_nonnull))` as an
`LLVM_ATTRIBUTE_RETURNS_NONNULL` definition
...in case anybody ever decides to run `/analyze` on LLVM (probably
myself, if anybody)
Reviewers: rnk, aaron.ballman
Differential Revision: http://reviews.llvm.org/D16751
llvm-svn: 260410
1. A macro with argument: LLVM_PACKED(StructDefinition)
2. A pair of macros defining scope of region with packing:
LLVM_PACKED_START
struct A { ... };
struct B { ... };
LLVM_PACKED_END
Differential Revision: http://reviews.llvm.org/D14337
llvm-svn: 252099
'inline' specifier. That specifier may or may not be valid for a given
function, or it may be required for correct linkage even when the
compiler doesn't support the always_inline attribute.
llvm-svn: 247252
This would have suppressed bug 24578, about use-after-
destroy on User and MDNode. Rolled back suppression for
the sake of code cleanliness, in preferance for bug
tracking to keep track of this issue.
This reverts commit 6ff2baabc4625d5b0a8dccf76aa0f72d930ea6c0.
llvm-svn: 246484
Remove support for Valgrind-based TSan, which hasn't been maintained for a
few years. We now use the TSan annotations only if LLVM is compiled with
-fsanitize=thread. We no longer need the weak function definitions as we
are guaranteed that our program is linked directly with the TSan runtime.
Differential Revision: http://reviews.llvm.org/D12121
llvm-svn: 245374
The value of this macro seems to be very low unless we actually start
using it everywhere, and I don't have immediate plans to make that
happen.
llvm-svn: 237941
MSVC 2013 requires the argument to __declspec(align()) to be an integer
constant expression that doesn't involve any identifiers like sizeof.
For GCC and Clang, LLVM_PTR_SIZE is equivalent to __SIZEOF_POINTER__,
which dates back to GCC 4.6 and Clang 2010. If that's not available, we
get sizeof(void*), which works with alignas() and
__attribute__((aligned())).
For MSVC, LLVM_PTR_SIZE is 4 or 8 depending on _WIN64.
llvm-svn: 233929
We wrap __attribute((aligned)) for GCC 4.7 and __declspec(align) for
MSVC. The latter behaves weird in some contexts so this should be used
carefully.
llvm-svn: 233910
On Windows, we now use RaiseException to generate the kind of trap we require (one which calls our vectored exception handler), and fall back to using a volatile write to simulate a trap elsewhere.
llvm-svn: 228691
between the linker's TLS optimizations and Clang's TLS code generation.
For now, Clang has been changed to disable linker TLS optimizations
until it (and LLVM more generally) are emitting TLS code sequences
compatible with the old bugs found in the linkers. That's a better fix
to handle bootstrapping on that platform.
llvm-svn: 227511
to get a powerpc64 host so that I can reproduce and test this, but it
only impacts that platform so trying the only other realistic option.
According to Ulrich, who debugged this initially, initial-exec is likely
to be sufficient for our needs and not subject to this bug. Will watch
the build bots to see.
If this doesn't work, I'll be forced to cut a really ugly pthread-based
approach into the primary user (our stack trace printing) as that user
cannot use the ThreadLocal implementation due to lifetime issues.
llvm-svn: 227414
entirely when threads are not enabled. This should allow anyone who
needs to bootstrap or cope with a host loader without TLS support to
limp along without threading support.
There is still some bug in the PPC TLS stuff that is not worked around.
I'm getting access to a machine to reproduce and debug this further.
There is some chance that I'll have to add a terrible workaround for
PPC.
There is also some problem with iOS, but I have no ability to really
evaluate what the issue is there. I'm leaving it to folks maintaining
that platform to suggest a path forward -- personally I don't see any
useful path forward that supports threading in LLVM but does so without
support for *very basic* TLS. Note that we don't need more than some
pointers, and we don't need constructors, destructors, or any of the
other fanciness which remains widely unimplemented.
llvm-svn: 227411
We shouldn't put this kind of attribute stuff in DataTypes.h.
Leave the END_WITH_NULL name for now so I can update clang without
making build spam.
llvm-svn: 221215
Unconditional noexcept support was added in the VS 2013 Nov CTP. Given
that there have been three CTPs since then, I don't think we need
careful macro magic to target that specific tech preview. Instead,
target the major release version number of 1900, which corresponds to
the as-yet unreleased VS "14".
llvm-svn: 221169
We have to use _MSC_FULL_VER here as CTP 2 and earlier didn't define
noexcept to my knowledge.
Fixes build error in lib/Support/Error.cpp when inheriting from
std::error_category, which has a noexcept virtual method.
llvm-svn: 221013
This requires incorporating __GNUC_PATCHLEVEL__ into our prerequisite
check, and renaming our __GNUC_PREREQ to LLVM_GNUC_PREREQ, since it is
now functionally different.
Patch by Chilledheart!
Differential Revision: http://reviews.llvm.org/D5879
llvm-svn: 220332
In both Clang and LLVM, this is a common pattern:
Size = sizeof(DeclRefExpr) + SomeExtraStuff;
void *Mem = Context.Allocate(Size, llvm::alignOf<DeclRefExpr>());
return new (Mem) DeclRefExpr(...);
The annoying thing is that because the default placement-new operator has a
nothrow specification, the compiler will insert a null check of Mem before
calling the DeclRefExpr constructor. This null check is redundant for us,
because we expect the allocation functions to never return null.
By annotating the allocator functions with returns_nonnull, we can optimize
away these checks. Compiling clang with a recent version of Clang and measuring
with:
$ perf stat -r20 bin/clang.patch -fsyntax-only -w gcc.c && perf stat -r20 bin/clang.orig -fsyntax-only -w gcc.c
Shows a 2.4% speed-up (+- 0.8%).
The pattern occurs in LLVM too. Measuring with -O3 (and now using bzip2.c
instead, because it's smaller):
$ perf stat -r20 bin/clang.patch -O3 -w bzip2.c && perf stat -r20 bin/clang.orig -O3 -w bzip2.c
Shows 4.4 % speed-up (+- 1%).
If anyone knows of a similar attribute we can use for MSVC, or some other
technique to get rid off the null check there, please let me know.
Differential Revision: http://reviews.llvm.org/D4989
llvm-svn: 216192
