[asan] don't unpoison redzones on function exit in use-after-return mode.

Summary:
Before this change the instrumented code before Ret instructions looked like:
  <Unpoison Frame Redzones>
  if (Frame != OriginalFrame) // I.e. Frame is fake
     <Poison Complete Frame>

Now the instrumented code looks like:
  if (Frame != OriginalFrame) // I.e. Frame is fake
     <Poison Complete Frame>
  else
     <Unpoison Frame Redzones>

Reviewers: eugenis

Reviewed By: eugenis

CC: llvm-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D2458

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197907 91177308-0d34-0410-b5e6-96231b3b80d8
Fix Scalarizer handling of vector GEPs with multiple index operands

The old code only worked for one index operand.  Also handle "inbounds".


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197908 91177308-0d34-0410-b5e6-96231b3b80d8
Fix Scalarizer insertion point when replacing PHIs with insertelements

If the Scalarizer scalarized a vector PHI but could not scalarize
all uses of it, it would insert a series of insertelements to reconstruct
the vector PHI value from the scalar ones.  The problem was that it would
emit these insertelements immediately after the PHI, even if there were
other PHIs after it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197909 91177308-0d34-0410-b5e6-96231b3b80d8