Lang Hames f9bddc40cd [ADT] Add a fallible_iterator wrapper. ... A fallible iterator is one whose increment or decrement operations may fail. This would usually be supported by replacing the ++ and -- operators with methods that return error: class MyFallibleIterator { public: // ... Error inc(); Errro dec(); // ... }; The downside of this style is that it no longer conforms to the C++ iterator concept, and can not make use of standard algorithms and features such as range-based for loops. The fallible_iterator wrapper takes an iterator written in the style above and adapts it to (mostly) conform with the C++ iterator concept. It does this by providing standard ++ and -- operator implementations, returning any errors generated via a side channel (an Error reference passed into the wrapper at construction time), and immediately jumping the iterator to a known 'end' value upon error. It also marks the Error as checked any time an iterator is compared with a known end value and found to be inequal, allowing early exit from loops without redundant error checking*. Usage looks like: MyFallibleIterator I = ..., E = ...; Error Err = Error::success(); for (auto &Elem : make_fallible_range(I, E, Err)) { // Loop body is only entered when safe. // Early exits from loop body permitted without checking Err. if (SomeCondition) return; } if (Err) // Handle error. * Since failure causes a fallible iterator to jump to end, testing that a fallible iterator is not an end value implicitly verifies that the error is a success value, and so is equivalent to an error check. Reviewers: dblaikie, rupprecht Subscribers: mgorny, dexonsmith, kristina, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D57618 llvm-svn: 353237		2019-02-05 23:17:11 +00:00
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AnyTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
APFloatTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
APIntTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
APSIntTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
ArrayRefTest.cpp	Revert r351954 "Add a value_type to ArrayRef."	2019-01-25 15:25:52 +00:00
BitmaskEnumTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
BitVectorTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
BreadthFirstIteratorTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
BumpPtrListTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
CMakeLists.txt	[ADT] Add a fallible_iterator wrapper.	2019-02-05 23:17:11 +00:00
DAGDeltaAlgorithmTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
DeltaAlgorithmTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
DenseMapTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
DenseSetTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
DepthFirstIteratorTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
EquivalenceClassesTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
FallibleIteratorTest.cpp	[ADT] Add a fallible_iterator wrapper.	2019-02-05 23:17:11 +00:00
FoldingSet.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
FunctionExtrasTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
FunctionRefTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
HashingTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
IListBaseTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
IListIteratorTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
IListNodeBaseTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
IListNodeTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
IListSentinelTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
IListTest.cpp	[ADT] Notify ilist traits about in-list transfers	2019-01-23 22:59:52 +00:00
ImmutableListTest.cpp	Replace llvm::isPodLike<...> by llvm::is_trivially_copyable<...>	2019-01-20 21:19:56 +00:00
ImmutableMapTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
ImmutableSetTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
IntEqClassesTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
IntervalMapTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
IntrusiveRefCntPtrTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
IteratorTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
MakeUniqueTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
MappedIteratorTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
MapVectorTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
OptionalTest.cpp	Fix compilation error with gcc 4.8	2019-01-21 18:21:03 +00:00
PackedVectorTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
PointerEmbeddedIntTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
PointerIntPairTest.cpp	Replace llvm::isPodLike<...> by llvm::is_trivially_copyable<...>	2019-01-20 21:19:56 +00:00
PointerSumTypeTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
PointerUnionTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
PostOrderIteratorTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
PriorityWorklistTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
RangeAdapterTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
SCCIteratorTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
ScopeExitTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
SequenceTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
SetVectorTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
SimpleIListTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
SmallPtrSetTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
SmallSetTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
SmallStringTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
SmallVectorTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
SparseBitVectorTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
SparseMultiSetTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
SparseSetTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
StatisticTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
STLExtrasTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
StringExtrasTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
StringMapTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
StringRefTest.cpp	Replace llvm::isPodLike<...> by llvm::is_trivially_copyable<...>	2019-01-20 21:19:56 +00:00
StringSwitchTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
TestGraph.h	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
TinyPtrVectorTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
TripleTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
TwineTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00
VariadicFunctionTest.cpp	Update the file headers across all of the LLVM projects in the monorepo	2019-01-19 08:50:56 +00:00