Merge isKnownNonNull into isKnownNonZero
It now knows the tricks of both functions.
Also, fix a bug that considered allocas of non-zero address space to be always non null
Differential Revision: https://reviews.llvm.org/D37628
llvm-svn: 312869
diff --git a/llvm/lib/Analysis/LazyValueInfo.cpp b/llvm/lib/Analysis/LazyValueInfo.cpp
index 9be773f..31f1d44 100644
--- a/llvm/lib/Analysis/LazyValueInfo.cpp
+++ b/llvm/lib/Analysis/LazyValueInfo.cpp
@@ -817,12 +817,12 @@
// definition. We could easily extend this to look through geps, bitcasts,
// and the like to prove non-nullness, but it's not clear that's worth it
// compile time wise. The context-insensitive value walk done inside
- // isKnownNonNull gets most of the profitable cases at much less expense.
+ // isKnownNonZero gets most of the profitable cases at much less expense.
// This does mean that we have a sensativity to where the defining
// instruction is placed, even if it could legally be hoisted much higher.
// That is unfortunate.
PointerType *PT = dyn_cast<PointerType>(BBI->getType());
- if (PT && isKnownNonNull(BBI)) {
+ if (PT && isKnownNonZero(BBI, DL)) {
Res = LVILatticeVal::getNot(ConstantPointerNull::get(PT));
return true;
}
@@ -901,7 +901,7 @@
// Before giving up, see if we can prove the pointer non-null local to
// this particular block.
if (Val->getType()->isPointerTy() &&
- (isKnownNonNull(Val) || isObjectDereferencedInBlock(Val, BB))) {
+ (isKnownNonZero(Val, DL) || isObjectDereferencedInBlock(Val, BB))) {
PointerType *PTy = cast<PointerType>(Val->getType());
Result = LVILatticeVal::getNot(ConstantPointerNull::get(PTy));
} else {
@@ -1886,17 +1886,17 @@
LazyValueInfo::getPredicateAt(unsigned Pred, Value *V, Constant *C,
Instruction *CxtI) {
// Is or is not NonNull are common predicates being queried. If
- // isKnownNonNull can tell us the result of the predicate, we can
+ // isKnownNonZero can tell us the result of the predicate, we can
// return it quickly. But this is only a fastpath, and falling
// through would still be correct.
+ const DataLayout &DL = CxtI->getModule()->getDataLayout();
if (V->getType()->isPointerTy() && C->isNullValue() &&
- isKnownNonNull(V->stripPointerCasts())) {
+ isKnownNonZero(V->stripPointerCasts(), DL)) {
if (Pred == ICmpInst::ICMP_EQ)
return LazyValueInfo::False;
else if (Pred == ICmpInst::ICMP_NE)
return LazyValueInfo::True;
}
- const DataLayout &DL = CxtI->getModule()->getDataLayout();
LVILatticeVal Result = getImpl(PImpl, AC, &DL, DT).getValueAt(V, CxtI);
Tristate Ret = getPredicateResult(Pred, C, Result, DL, TLI);
if (Ret != Unknown)