[NFC] Refactor SafepointIRVerifier
[NFC] Refactor SafepointIRVerifier

Now two classes are responsible for verification: one of them can track GC
pointers and know whether a pointer is relocated or not and another based on
that information can verify uses of GC pointers.

Patch Author: Daniil Suchkov
Reviewers: mkazantsev, anna, apilipenko
Reviewed By: mkazantsev
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D40885


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@320549 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/llvm,apple/swift-llvm,apple/swift-llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,apple/swift-llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,apple/swift-llvm