diff options
author | Serge Guelton <sguelton@quarkslab.com> | 2019-01-20 21:19:56 +0000 |
---|---|---|
committer | Serge Guelton <sguelton@quarkslab.com> | 2019-01-20 21:19:56 +0000 |
commit | be88539b85204041f727ec6499315884b3d886b0 (patch) | |
tree | c6fcb530c4555e3ea4efa1bbbeced22ed7572a57 /llvm/tools/llvm-diff/DifferenceEngine.cpp | |
parent | 7ac79ed8f0b50640e2809b9f230f87f1b68baa53 (diff) | |
download | llvm-be88539b85204041f727ec6499315884b3d886b0.zip llvm-be88539b85204041f727ec6499315884b3d886b0.tar.gz llvm-be88539b85204041f727ec6499315884b3d886b0.tar.bz2 |
Replace llvm::isPodLike<...> by llvm::is_trivially_copyable<...>
As noted in https://bugs.llvm.org/show_bug.cgi?id=36651, the specialization for
isPodLike<std::pair<...>> did not match the expectation of
std::is_trivially_copyable which makes the memcpy optimization invalid.
This patch renames the llvm::isPodLike trait into llvm::is_trivially_copyable.
Unfortunately std::is_trivially_copyable is not portable across compiler / STL
versions. So a portable version is provided too.
Note that the following specialization were invalid:
std::pair<T0, T1>
llvm::Optional<T>
Tests have been added to assert that former specialization are respected by the
standard usage of llvm::is_trivially_copyable, and that when a decent version
of std::is_trivially_copyable is available, llvm::is_trivially_copyable is
compared to std::is_trivially_copyable.
As of this patch, llvm::Optional is no longer considered trivially copyable,
even if T is. This is to be fixed in a later patch, as it has impact on a
long-running bug (see r347004)
Note that GCC warns about this UB, but this got silented by https://reviews.llvm.org/D50296.
Differential Revision: https://reviews.llvm.org/D54472
llvm-svn: 351701
Diffstat (limited to 'llvm/tools/llvm-diff/DifferenceEngine.cpp')
-rw-r--r-- | llvm/tools/llvm-diff/DifferenceEngine.cpp | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/llvm/tools/llvm-diff/DifferenceEngine.cpp b/llvm/tools/llvm-diff/DifferenceEngine.cpp index a1c6005..bc93ece 100644 --- a/llvm/tools/llvm-diff/DifferenceEngine.cpp +++ b/llvm/tools/llvm-diff/DifferenceEngine.cpp @@ -67,7 +67,7 @@ public: unsigned NewSize = Storage.size() - 1; if (NewSize) { // Move the slot at the end to the beginning. - if (isPodLike<T>::value) + if (is_trivially_copyable<T>::value) Storage[0] = Storage[NewSize]; else std::swap(Storage[0], Storage[NewSize]); |