Don't shrink atomic ops to bool in GlobalOpt.

LLVM IR doesn't currently allow atomic bool load/store operations, and the
transformation is dubious anyway because it isn't profitable on all platforms.

PR17163.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190357 91177308-0d34-0410-b5e6-96231b3b80d8
white spaces and long lines

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190358 91177308-0d34-0410-b5e6-96231b3b80d8
mi-sched: smooth out the cyclicpath heuristic.

Arnold's idea.

I generally try to avoid stateful heuristics because it can make
debugging harder. However, we need a way to prevent the latency
priority from dominating, and it somewhat makes sense to schedule
aggressively for latency only within an issue group.

Swift in particular likes this, and it doesn't hurt anyone else:
| Benchmarks/MiBench/consumer-lame              |  10.39% |
| Benchmarks/Misc/himenobmtxpa                  |   9.63% |

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190360 91177308-0d34-0410-b5e6-96231b3b80d8
Debug Info: move DIScope::getContext back from DwarfDebug.

This partially reverts r190330. DIScope::getContext now returns DIScopeRef
instead of DIScope. We construct a DIScopeRef from DIScope when we are
dealing with subprogram, lexical block or name space.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190362 91177308-0d34-0410-b5e6-96231b3b80d8