Summary: Add SaturatingMultiplyAdd convenience function template since A + (X * Y) comes up frequently when doing weighted arithmetic.
Reviewers: davidxl, silvas
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D15385
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@257532 91177308-0d34-0410-b5e6-96231b3b80d8