return false;
}
-void LoopDependenceAnalysis::analysePair(DependencePair *P) const {
+LoopDependenceAnalysis::DependenceResult
+LoopDependenceAnalysis::analysePair(DependencePair *P) const {
DEBUG(errs() << "Analysing:\n" << *P->A << "\n" << *P->B << "\n");
- // Our default answer: we don't know anything, i.e. we failed to analyse this
- // pair to get a more specific answer (dependent, independent).
- P->Result = Unknown;
-
// We only analyse loads and stores but no possible memory accesses by e.g.
// free, call, or invoke instructions.
if (!IsLoadOrStoreInst(P->A) || !IsLoadOrStoreInst(P->B)) {
DEBUG(errs() << "--> [?] no load/store\n");
- return;
+ return Unknown;
}
Value *aPtr = GetPointerOperand(P->A);
case AliasAnalysis::MayAlias:
// We can not analyse objects if we do not know about their aliasing.
DEBUG(errs() << "---> [?] may alias\n");
- return;
+ return Unknown;
case AliasAnalysis::NoAlias:
// If the objects noalias, they are distinct, accesses are independent.
DEBUG(errs() << "---> [I] no alias\n");
- P->Result = Independent;
- return;
+ return Independent;
case AliasAnalysis::MustAlias:
break; // The underlying objects alias, test accesses for dependence.
}
+ // We failed to analyse this pair to get a more specific answer.
DEBUG(errs() << "---> [?] cannot analyse\n");
- return;
+ return Unknown;
}
bool LoopDependenceAnalysis::depends(Value *A, Value *B) {
if (!findOrInsertDependencePair(A, B, p)) {
// The pair is not cached, so analyse it.
++NumAnalysed;
- analysePair(p);
- switch (p->Result) {
+ switch (p->Result = analysePair(p)) {
case Dependent: ++NumDependent; break;
case Independent: ++NumIndependent; break;
case Unknown: ++NumUnknown; break;