Llvm Statepoint Utils Versions Save

Improved performance by ~25% in heavy usage situations, such as a program with heavy recursion that triggers the garbage collector often. The main bottleneck when parsing stack frames is lookup_return_address, which used 64-bit integer division to compute the hash table's bucket index. I've rounded up the number of entries to be a power-of-two and use a bitwise-AND instead.

Changes:

• Fixed bug: Non-indirect locations end up as bogus stack frame offsets
• The header file now has support for inclusion in C++ projects.
• Numerous fixes for the example driver under the test directory to support both Linux and macOS.

This release adds a make unified target that rolls together the headers and sources into a single file, respectively. The products of that target are attached to this release, inside unified-source.tar.

This release only supports LLVM 4.

This version supports LLVM Stackmap version 3. This version is found in at least LLVM 5 and 6.