search for: d5896

...if a C builtin function has an equivalent llvm intrinsic, that the intrinsic be the preferred form. The equivalent clang __builtin should emit the intrinsic, and SimplifyLibCalls should replace calls with the intrinsic. For context, this came up on an old review thread: http://reviews.llvm.org/D5896 There are a few motivations for this: 1. Intrinsics have additional properties that help optimizations. They are more widely considered by optimization passes, such as being vectorizable and speculatively executable. 2. More useful for targets where the concept of libcalls is not useful. On GP...