[X86] Use LoadInst->getType() instead of LoadInst->getPointerOperandType()->getElementType(). NFCI

For the future day when the pointer's don't have element types, we shoudl just use the type of the load result instead.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@356721 91177308-0d34-0410-b5e6-96231b3b80d8

Author: topperc

lib/Target/X86/X86ISelLowering.cpp

@@ -25497,9 +25497,8 @@ bool X86TargetLowering::shouldExpandAtomicStoreInIR(StoreInst *SI) const {
 // FIXME: On 32 bits x86, fild/movq might be faster than lock cmpxchg8b.
 TargetLowering::AtomicExpansionKind
 X86TargetLowering::shouldExpandAtomicLoadInIR(LoadInst *LI) const {
-  auto PTy = cast<PointerType>(LI->getPointerOperandType());
-  return needsCmpXchgNb(PTy->getElementType()) ? AtomicExpansionKind::CmpXChg
-                                               : AtomicExpansionKind::None;
+  return needsCmpXchgNb(LI->getType()) ? AtomicExpansionKind::CmpXChg
+                                       : AtomicExpansionKind::None;
 }
 
 TargetLowering::AtomicExpansionKind