If a section is rw, it is irrelevant if the dynamic linker will write to
it or not.
It looks like llvm implemented this because gcc was doing it. It looks
like gcc implemented this in the hope that it would put all the
relocated items close together and speed up the dynamic linker.
There are two problem with this:
* It doesn't work. Both bfd and gold will map .data.rel to .data and
concatenate the input sections in the order they are seen.
* If we want a feature like that, it can be implemented directly in the
linker since it knowns where the dynamic relocations are.
llvm-svn: 253436
Use `__builtin_offsetof` in place of `offsetof`. Certain environments provide a
macro definition of `offsetof` which may end up causing issues. This was
observed on Windows. Use `__builtin_offsetof` to ensure correct evaluation
everywhere. NFC.
llvm-svn: 253435
This patch emits a more appropriate (but still noisy) diagnostic stream when a lambda-expression is encountered within a non-type default argument.
For e.g. template<int N = ([] { return 5; }())> int f();
As opposed to complaining that a lambda expression is not allowed in an unevaluated operand, the patch complains about the lambda being forbidden in a constant expression context (which will be allowed in C++17 now that they have been accepted by EWG, unless of course CWG or national bodies (that have so far shown no signs of concern) rise in protest)
As I start submitting patches for constexpr lambdas (http://wg21.link/P0170R0) under C++1z (OK'd by Richard Smith at Kona), this will be one less change to make.
Thanks!
llvm-svn: 253431
Most linked executables do not have a symbol table in COFF.
However, it is pretty typical to have some export entries. Use those
entries to inform the disassembler about potential function definitions
and call targets.
llvm-svn: 253429
This commit is for a later patch that is depend on it. The sum of two
branch probabilities can be greater than 1 due to rounding. It is safer
to saturate the results of sum and subtraction.
llvm-svn: 253421
unsafe, since many operations on the types can trigger lazy deserialization of
more types and invalidate the iterators. This fixes a crasher, but I've not
been able to reduce it to a reasonable testcase yet.
llvm-svn: 253420
When looking for the best successor from the outer loop for a block
belonging to an inner loop, the edge probability computation can be
improved so that edges in the inner loop are ignored. For example,
suppose we are building chains for the non-loop part of the following
code, and looking for B1's best successor. Assume the true body is very
hot, then B3 should be the best candidate. However, because of the
existence of the back edge from B1 to B0, the probability from B1 to B3
can be very small, preventing B3 to be its successor. In this patch, when
computing the probability of the edge from B1 to B3, the weight on the
back edge B1->B0 is ignored, so that B1->B3 will have 100% probability.
if (...)
do {
B0;
... // some branches
B1;
} while(...);
else
B2;
B3;
Differential revision: http://reviews.llvm.org/D10825
llvm-svn: 253414
Summary:
This change adds MathExtras helper functions for handling unsigned, saturating addition and multiplication. It also updates the instrumentation and sample profile merge implementations to use them.
No functional changes.
Reviewers: dnovillo, bogner, davidxl
Subscribers: davidxl, llvm-commits
Differential Revision: http://reviews.llvm.org/D14720
llvm-svn: 253412
While still allowing CodeGen/AsmPrinter in llvm to own them using a bump
ptr allocator. (might be nice to replace the pointers there with
something that at least automatically calls their dtors, if that's
necessary/useful, rather than having it done explicitly (I think a typed
BumpPtrAllocator already does this, or maybe a unique_ptr with a custom
deleter, etc))
llvm-svn: 253409
Currently, when there is a global register variable in a program that
is bound to an invalid register, clang/llvm prints an error message that
is not very user-friendly.
This commit improves the diagnostic and moves the check that used to be
in the backend to Sema. In addition, it makes changes to error out if
the size of the register doesn't match the declared variable size.
e.g., volatile register int B asm ("rbp");
rdar://problem/23084219
Differential Revision: http://reviews.llvm.org/D13834
llvm-svn: 253405
The logic for handling the pattern without a shift is identical
to the logic for handling the pattern with a shift if you set
the shift amount to zero for the former.
This should make it easier to see that we probably don't even need
optimizeIntToFloatBitCast().
If we call something like foldVecTruncToExtElt() from visitTrunc(),
we'll solve PR25543:
https://llvm.org/bugs/show_bug.cgi?id=25543
llvm-svn: 253403
Summary:
This check flags all array subscriptions on static arrays and
std::arrays that either have a non-compile-time-constant index or are
out of bounds.
Dynamic accesses into arrays are difficult for both tools and humans to
validate as safe. array_view is a bounds-checked, safe type for
accessing arrays of data. at() is another alternative that ensures
single accesses are bounds-checked. If iterators are needed to access an
array, use the iterators from an array_view constructed over the array.
This rule is part of the "Bounds safety" profile of the C++ Core
Guidelines, see
https://github.com/isocpp/CppCoreGuidelines/blob/master/CppCoreGuidelines.md#-bounds2-only-index-into-arrays-using-constant-expressions
Reviewers: alexfh, sbenza, bkramer, aaron.ballman
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D13746
llvm-svn: 253401
Missed bit of feedback from D14720.
Show the same "Make sure that all profile
data to be merged is generated from the same binary." hint for hash mismatch
and value site count mismatch as we now do for counter mismatch when merging
incompatible instrumentation profile data.
llvm-svn: 253400
other than the top level, we issue an error. This breaks a fair amount of C++
code wrapping C libraries, where the C library is #included within a namespace
/ extern "C" combination, because the C library (probably) includes C++
standard library headers which may be within modules.
Without modules, this setup is harmless if (and *only* if) the corresponding
standard library module was already included outside the namespace, so
downgrade the error to a default-error extension in that case, so that it can
be selectively disabled for such misbehaving libraries.
llvm-svn: 253398
Verified that this was at least /an/ issue, if not the only one, by
initializing NumBuckets to 1 (previously it was uninitialized, so if
this change made a difference, which it did (causing a bunch of tests to
crash) it demonstrates use-of-uninitialized memory). Initializing then
removes the crashes.
Thanks Reid for the debugging assistance
llvm-svn: 253395
Currently clang requires several additional command
line options in order to enable new features needed
during CUDA compilation. This patch makes these
options default.
* Automatically include cuda_runtime.h if we've found
a valid CUDA installation.
* Disable automatic CUDA header inclusion during unit tests.
* Added test case for command line construction.
* Enabled target overloads and relaxed call checks that are
needed in order to include CUDA headers.
* Added CUDA-7.5 installation path to the CUDA installation search list.
* Define __CUDA__ macro to indicate CUDA compilation.
llvm-svn: 253389
Header files that come with CUDA are assuming split host/device
compilation and are not usable by clang out of the box.
With a bit of preprocessor magic it's possible to twist them
into something clang can use.
This wrapper always includes CUDA headers exactly the same way during
host and device compilation passes and produces identical preprocessed
content during host and device side compilation for sm_35 GPUs. Device
compilation passes for older GPUs will see a smaller subset of device
functions supported by particular GPU.
The wrapper assumes specific contents of CUDA header files and works
only with CUDA 7.0 and 7.5.
Differential Revision: http://reviews.llvm.org/D13171
llvm-svn: 253388
- added detection of libdevice bitcode file and API to find one appropriate for the GPU we're compiling for.
- pass additional cc1 options for linking with detected libdevice bitcode
- added -nocudalib to prevent automatic linking with libdevice
- added test cases to verify new functionality
Differential Revision: http://reviews.llvm.org/D14556
llvm-svn: 253387
In order to compile a CUDA file clang must be able to find
include files for both both host and device.
This patch passes AuxToolchain to AddPreprocessingOptions and
uses it to add include paths for the opposite side of compilation.
We also must be able to find CUDA include files. If the driver
found CUDA installation, it adds appropriate include path
to CUDA headers. This can be disabled with '-nocudainc'.
- Added include paths for the opposite side of compilation.
- Added include paths to detected CUDA installation.
- Added -nocudainc to prevent adding CUDA include path.
- Added test cases to verify new functionality.
Differential Revision: http://reviews.llvm.org/D13170
llvm-svn: 253386
Rafael Espindola