MemoryBuiltins:

MemoryBuiltins:
 - recognize C++ new(std::nothrow) friends
 - ignore ExtractElement and ExtractValue instructions in size/offset analysis (all easy cases are probably folded away before we get here)
 - also recognize realloc as noalias

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159356 91177308-0d34-0410-b5e6-96231b3b80d8