Simplify the code a bit.

The compact unwind registers were defined in two different
places. It's better just to place them in the function that uses them
and specify that this is a 64-bit or 32-bit machine.

No functionality change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181529 91177308-0d34-0410-b5e6-96231b3b80d8
Hexagon: Use relation map for getMatchingCondBranchOpcode() and 
getInvertedPredicatedOpcode() functions instead of switch cases.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181530 91177308-0d34-0410-b5e6-96231b3b80d8
[GVN] Split critical-edge on the fly, instead of postpone edge-splitting to next
  iteration.
  
  This on step toward non-iterative GVN. My local hack suggests that getting rid
of iteration will speedup GVN by 30%+ on a medium sized input (2k LOC, C++).
I cannot explain why not 2x or more at this moment.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181532 91177308-0d34-0410-b5e6-96231b3b80d8