[Attributor] Clamp operator to extend known state
[Attributor] Clamp operator to extend known state

Summary:
Similar to `^=` operator for IntegerState, this patch introduces a `+=` operator to "clamp" known information.

Reviewers: jdoerfert, sstefan1

Reviewed By: jdoerfert

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66635

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@370015 91177308-0d34-0410-b5e6-96231b3b80d8

GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm