Prototype and playground for generating stack maps to garbage-collected objects
using clang/llvm infrastructure.
Design doc: https://bit.ly/chromium-stack-maps
Building and Running Tests:
1. Build the gc libary
`mkdir gc/build/ && cd gc/build`
`cmake ../ && make`
2. Build the LLVM passes:
`mkdir ../../build/ && cd ../../build/`
`cmake ../ && make all`
3. Run the tests (from stack_maps/tests/)
`./test.py <path_to_chromium_llvm_bin_dir> ../gc/build/libGC.a \
../build/IdentifySafepoints/libLLVMIdentifySafepointsPass.so \
../build/RegisterGcFunctionsPass.so`