Create instruction classes for identifying any atomicity of memory intrinsic. (NFC)

Create instruction classes for identifying any atomicity of memory intrinsic. (NFC)

Summary:
For reference, see: http://lists.llvm.org/pipermail/llvm-dev/2017-August/116589.html

This patch fleshes out the instruction class hierarchy with respect to atomic and
non-atomic memory intrinsics. With this change, the relevant part of the class
hierarchy becomes:

IntrinsicInst
  -> MemIntrinsicBase (methods-only class)
    -> MemIntrinsic (non-atomic intrinsics)
      -> MemSetInst
      -> MemTransferInst
        -> MemCpyInst
        -> MemMoveInst
    -> AtomicMemIntrinsic (atomic intrinsics)
      -> AtomicMemSetInst
      -> AtomicMemTransferInst
        -> AtomicMemCpyInst
        -> AtomicMemMoveInst
    -> AnyMemIntrinsic (both atomicities)
      -> AnyMemSetInst
      -> AnyMemTransferInst
        -> AnyMemCpyInst
        -> AnyMemMoveInst

This involves some class renaming:
    ElementUnorderedAtomicMemCpyInst -> AtomicMemCpyInst
    ElementUnorderedAtomicMemMoveInst -> AtomicMemMoveInst
    ElementUnorderedAtomicMemSetInst -> AtomicMemSetInst
A script for doing this renaming in downstream trees is included below.

An example of where the Any* classes should be used in LLVM is when reasoning
about the effects of an instruction (ex: aliasing).

---
Script for renaming AtomicMem* classes:
PREFIXES="[<,([:space:]]"
CLASSES="MemIntrinsic|MemTransferInst|MemSetInst|MemMoveInst|MemCpyInst"
SUFFIXES="[;)>,[:space:]]"

REGEX="(${PREFIXES})ElementUnorderedAtomic(${CLASSES})(${SUFFIXES})"
REGEX2="visitElementUnorderedAtomic(${CLASSES})"

FILES=$( grep -E "(${REGEX}|${REGEX2})" -r . | tr ':' ' ' | awk '{print $1}' | sort | uniq )

SED_SCRIPT="s~${REGEX}~\1Atomic\2\3~g"
SED_SCRIPT2="s~${REGEX2}~visitAtomic\1~g"

for f in $FILES; do
    echo "Processing: $f"
    sed  -i ".bak" -E "${SED_SCRIPT};${SED_SCRIPT2};${EA_SED_SCRIPT};${EA_SED_SCRIPT2}" $f
done

Reviewers: sanjoy, deadalnix, apilipenko, anna, skatkov, mkazantsev

Reviewed By: sanjoy

Subscribers: hfinkel, jholewinski, arsenm, sdardis, nhaehnle, JDevlieghere, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D38419

llvm-svn: 316950