path::const_iterator claims that it's a bidirectional iterator, but it
doesn't satisfy all of the contracts for a bidirectional iterator.
For example, n3376 24.2.5 p6 says "If a and b are both dereferenceable,
then a == b if and only if *a and *b are bound to the same object",
but this doesn't work with how we stash and recreate Components.
This means that our use of reverse_iterator on this type is invalid
and leads to many of the valgrind errors we're hitting, as explained
by Tilmann Scheller here:
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20140728/228654.html
Instead, we admit that path::const_iterator is only an input_iterator,
and implement a second input_iterator for path::reverse_iterator (by
changing const_iterator::operator-- to reverse_iterator::operator++).
All of the uses of this just traverse once over the path in one
direction or the other anyway.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214737 91177308-0d34-0410-b5e6-96231b3b80d8
This reflects the common use case of nativizing a prepared path. The existing
version invokes undefined behavior if input = output, add an assert to catch
that case.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190510 91177308-0d34-0410-b5e6-96231b3b80d8
Most clients have already been moved from Path V1 to V2. The ones using V1
now include PathV1.h explicitly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183801 91177308-0d34-0410-b5e6-96231b3b80d8
