Author: Kazu Hirata Date: 2021-01-18T10:16:34-08:00 New Revision: dc300beba7a849aac44c39ccc450a575db99bc14
URL: https://github.com/llvm/llvm-project/commit/dc300beba7a849aac44c39ccc450a575db99bc14 DIFF: https://github.com/llvm/llvm-project/commit/dc300beba7a849aac44c39ccc450a575db99bc14.diff LOG: [STLExtras] Add a default value to drop_begin This patch adds the default value of 1 to drop_begin. In the llvm codebase, 70% of calls to drop_begin have 1 as the second argument. The interface similar to with std::next should improve readability. This patch converts a couple of calls to drop_begin as examples. Differential Revision: https://reviews.llvm.org/D94858 Added: Modified: llvm/include/llvm/ADT/STLExtras.h llvm/lib/Transforms/Utils/LoopUtils.cpp llvm/unittests/ADT/STLExtrasTest.cpp Removed: ################################################################################ diff --git a/llvm/include/llvm/ADT/STLExtras.h b/llvm/include/llvm/ADT/STLExtras.h index c8c1aff9f2dd..63c7f48a5bd2 100644 --- a/llvm/include/llvm/ADT/STLExtras.h +++ b/llvm/include/llvm/ADT/STLExtras.h @@ -272,7 +272,7 @@ template <typename ContainerTy> bool hasSingleElement(ContainerTy &&C) { /// Return a range covering \p RangeOrContainer with the first N elements /// excluded. -template <typename T> auto drop_begin(T &&RangeOrContainer, size_t N) { +template <typename T> auto drop_begin(T &&RangeOrContainer, size_t N = 1) { return make_range(std::next(adl_begin(RangeOrContainer), N), adl_end(RangeOrContainer)); } diff --git a/llvm/lib/Transforms/Utils/LoopUtils.cpp b/llvm/lib/Transforms/Utils/LoopUtils.cpp index 401fe450ebad..e6575ee2caf2 100644 --- a/llvm/lib/Transforms/Utils/LoopUtils.cpp +++ b/llvm/lib/Transforms/Utils/LoopUtils.cpp @@ -349,7 +349,7 @@ Optional<MDNode *> llvm::makeFollowupLoopID( bool Changed = false; if (InheritAllAttrs || InheritSomeAttrs) { - for (const MDOperand &Existing : drop_begin(OrigLoopID->operands(), 1)) { + for (const MDOperand &Existing : drop_begin(OrigLoopID->operands())) { MDNode *Op = cast<MDNode>(Existing.get()); auto InheritThisAttribute = [InheritSomeAttrs, @@ -386,7 +386,7 @@ Optional<MDNode *> llvm::makeFollowupLoopID( continue; HasAnyFollowup = true; - for (const MDOperand &Option : drop_begin(FollowupNode->operands(), 1)) { + for (const MDOperand &Option : drop_begin(FollowupNode->operands())) { MDs.push_back(Option.get()); Changed = true; } diff --git a/llvm/unittests/ADT/STLExtrasTest.cpp b/llvm/unittests/ADT/STLExtrasTest.cpp index 01968171b832..862653055417 100644 --- a/llvm/unittests/ADT/STLExtrasTest.cpp +++ b/llvm/unittests/ADT/STLExtrasTest.cpp @@ -400,6 +400,17 @@ TEST(STLExtrasTest, DropBeginTest) { } } +TEST(STLExtrasTest, DropBeginDefaultTest) { + SmallVector<int, 5> vec{0, 1, 2, 3, 4}; + + int i = 1; + for (auto &v : drop_begin(vec)) { + EXPECT_EQ(v, i); + i += 1; + } + EXPECT_EQ(i, 5); +} + TEST(STLExtrasTest, EarlyIncrementTest) { std::list<int> L = {1, 2, 3, 4}; _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
