GEP index sinking fixes:

GEP index sinking fixes:
1) Take address scale into consideration. e.g. i32* -> scale 4.
2) Examine all the users of GEP.
3) Generalize to inter-block GEP's (no longer uses loopinfo).
4) Don't do xform if GEP has other variable index(es).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35403 91177308-0d34-0410-b5e6-96231b3b80d8