If-converter models predicated defs as read + write. The read should be marked as 'undef' since it may not already be live. This appeases -verify-machineinstrs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157662 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed