Add an interface to scale the frequencies of a set of blocks.

The scaling is done with reference to the the new frequency of a reference block.

Differential Revision: https://reviews.llvm.org/D28535

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292507 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed