1. [ARM] Change VPT state assertion (details)
  2. [RDA] Switch isSafeToMove iterators (details)
Commit 195c22f2733cf923b932412f0fe212f4ef397d2c by sam.parker
[ARM] Change VPT state assertion

Just because we haven't encountered an instruction setting the VPR,
it doesn't mean we can't create a VPT block - the VPR maybe a

Differential Revision:
The file was addedllvm/test/CodeGen/Thumb2/LowOverheadLoops/begin-vpt-without-inst.mir
The file was modifiedllvm/lib/Target/ARM/ARMLowOverheadLoops.cpp
Commit 700f93e92b6d4cdbab66133f75c143c9677f2d41 by sam.parker
[RDA] Switch isSafeToMove iterators

So forwards is forwards and backwards is reverse. Also add a check
so that we know the instructions are in the expected order.

Differential Revision:
The file was modifiedllvm/test/CodeGen/Thumb2/LowOverheadLoops/it-block-mov.mir
The file was modifiedllvm/test/CodeGen/Thumb2/LowOverheadLoops/lstp-insertion-position.mir
The file was modifiedllvm/test/CodeGen/Thumb2/LowOverheadLoops/mov-operand.ll
The file was modifiedllvm/test/CodeGen/Thumb2/LowOverheadLoops/move-def-before-start.mir
The file was modifiedllvm/test/CodeGen/Thumb2/LowOverheadLoops/move-start-after-def.mir
The file was modifiedllvm/lib/CodeGen/ReachingDefAnalysis.cpp