[ADT] Fix a confusing interface spec and some annoying peculiarities with the StringRef::split method when used with a MaxSplit argument other than '-1' (which nobody really does today, but which should actually work). The spec claimed both to split up to MaxSplit times, but also to append <= MaxSplit strings to the vector. One of these doesn't make sense. Given the name "MaxSplit", let's go with it being a max over how many *splits* occur, which means the max on how many strings get appended is MaxSplit+1. I'm not actually sure the implementation correctly provided this logic either, as it used a really opaque loop structure. The implementation was also playing weird games with nullptr in the data field to try to rely on a totally opaque hidden property of the split method that returns a pair. Nasty IMO. Replace all of this with what is (IMO) simpler code that doesn't use the pair returning split method, and instead just finds each separator and appends directly. I think this is a lot easier to read, and it most definitely matches the spec. Added some tests that exercise the corner cases around StringRef() and StringRef("") that all now pass. I'll start using this in code in the next commit. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@247249 91177308-0d34-0410-b5e6-96231b3b80d8
[ADT] Add a single-character version of the small vector split routine on StringRef. Finding and splitting on a single character is substantially faster than doing it on even a single character StringRef -- we immediately get to a *very* tuned memchr call this way. Even nicer, we get to this even in a debug build, shaving 18% off the runtime of TripleTest.Normalization, helping PR23676 some more. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@247244 91177308-0d34-0410-b5e6-96231b3b80d8
Retire llvm::array_endof in favor of non-member std::end. While there make array_lengthof constexpr if we have support for it. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206112 91177308-0d34-0410-b5e6-96231b3b80d8
Fix layering StringRef copy using BumpPtrAllocator. Now to copy a string into a BumpPtrAllocator and get a StringRef to the copy: StringRef myCopy = myStr.copy(myAllocator); git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200885 91177308-0d34-0410-b5e6-96231b3b80d8
Roll back the ConstStringRef change for now There are a couple of interesting things here that we want to check over (particularly the expecting asserts in StringRef) and get right for general use in ADT so hold back on this one. For clang we have a workable templated solution to use in the meanwhile. This reverts commit r200187. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200194 91177308-0d34-0410-b5e6-96231b3b80d8
StringRef: Extend constexpr capabilities and introduce ConstStringRef (1) Add llvm_expect(), an asserting macro that can be evaluated as a constexpr expression as well as a runtime assert or compiler hint in release builds. This technique can be used to construct functions that are both unevaluated and compiled depending on usage. (2) Update StringRef using llvm_expect() to preserve runtime assertions while extending the same checks to static asserts in C++11 builds that support the feature. (3) Introduce ConstStringRef, a strong subclass of StringRef that references compile-time constant strings. It's convertible to, but not from, ordinary StringRef and thus can be used to add compile-time safety to various interfaces in LLVM and clang that only accept fixed inputs such as diagnostic format strings that tend to get misused. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200187 91177308-0d34-0410-b5e6-96231b3b80d8
Re-sort all of the includes with ./utils/sort_includes.py so that subsequent changes are easier to review. About to fix some layering issues, and wanted to separate out the necessary churn. Also comment and sink the include of "Windows.h" in three .inc files to match the usage in Memory.inc. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198685 91177308-0d34-0410-b5e6-96231b3b80d8
Add {start,end}with_lower methods to StringRef. startswith_lower is ocassionally useful and I think worth adding. endwith_lower is added for completeness. Differential Revision: http://llvm-reviews.chandlerc.com/D2041 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193706 91177308-0d34-0410-b5e6-96231b3b80d8
Add a few tests for StringRef::{start,end}with. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193550 91177308-0d34-0410-b5e6-96231b3b80d8
Add a Python-like join function to merge a list of strings with a separator between each two elements. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@189846 91177308-0d34-0410-b5e6-96231b3b80d8
Sort the #include lines for unittest/... git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169250 91177308-0d34-0410-b5e6-96231b3b80d8
Use unsigned long long instead of uin64_t for OS where that matters. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165147 91177308-0d34-0410-b5e6-96231b3b80d8
Don't call getAsUnsignedInteger directly, it fails to compile if uint64_t is not "unsigned long long". while there add more test cases. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165140 91177308-0d34-0410-b5e6-96231b3b80d8
Add getAsUnsignedInteger test case that checks that known bad values are rejected git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165136 91177308-0d34-0410-b5e6-96231b3b80d8
[Support/StringRef] Add find_last_not_of and {r,l,}trim. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156652 91177308-0d34-0410-b5e6-96231b3b80d8
Fix warnings. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152522 91177308-0d34-0410-b5e6-96231b3b80d8
Make StringRef::getAsInteger work with all integer types. Before this change it would fail with {,u}int64_t on x86-64 Linux. This also removes code duplication. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152517 91177308-0d34-0410-b5e6-96231b3b80d8
Add generic support for hashing StringRef objects using the new hashing library. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152003 91177308-0d34-0410-b5e6-96231b3b80d8
Add a bad char heuristic to StringRef::find. Based on Horspool's simplified version of Boyer-Moore. We use a constant-sized table of uint8_ts to keep cache thrashing low, needles bigger than 255 bytes are uncommon anyways. The worst case is still O(n*m) but we do a lot better on the average case now. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142061 91177308-0d34-0410-b5e6-96231b3b80d8
Fix a bug in compare_numeric(). Thanks to Alexandru Dura and Jonas Paulsson for finding it. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140859 91177308-0d34-0410-b5e6-96231b3b80d8