Commit 89a44b0f authored by Philip Reames's avatar Philip Reames Committed by Philip Reames
Browse files

[LAA] Use early return [nfc]

parent 6cd3343b

llvm/lib/Analysis/LoopAccessAnalysis.cpp

+17 −17
Original line number Diff line number Diff line
@@ -1414,19 +1414,19 @@ std::optional<int64_t> llvm::getPtrStride(PredicatedScalarEvolution &PSE, 
    isNoWrapAddRec(Ptr, AR, PSE, Lp);

  if (!IsNoWrapAddRec && !IsInBoundsGEP &&

      NullPointerIsDefined(Lp->getHeader()->getParent(), AddrSpace)) {

    if (Assume) {

    if (!Assume) {

      LLVM_DEBUG(

          dbgs() << "LAA: Bad stride - Pointer may wrap in the address space "

                 << *Ptr << " SCEV: " << *AR << "\n");

      return std::nullopt;

    }



    PSE.setNoOverflow(Ptr, SCEVWrapPredicate::IncrementNUSW);

    IsNoWrapAddRec = true;

    LLVM_DEBUG(dbgs() << "LAA: Pointer may wrap in the address space:\n"

                      << "LAA:   Pointer: " << *Ptr << "\n"

                      << "LAA:   SCEV: " << *AR << "\n"

                      << "LAA:   Added an overflow assumption\n");

    } else {

      LLVM_DEBUG(

          dbgs() << "LAA: Bad stride - Pointer may wrap in the address space "

                 << *Ptr << " SCEV: " << *AR << "\n");

      return std::nullopt;

    }

  }



  // Check the step is constant.
@@ -1463,7 +1463,9 @@ std::optional<int64_t> llvm::getPtrStride(PredicatedScalarEvolution &PSE, 
  if (!IsNoWrapAddRec && Stride != 1 && Stride != -1 &&

      (IsInBoundsGEP || !NullPointerIsDefined(Lp->getHeader()->getParent(),

                                              AddrSpace))) {

    if (Assume) {

    if (!Assume)

      return std::nullopt;



    // We can avoid this case by adding a run-time check.

    LLVM_DEBUG(dbgs() << "LAA: Non unit strided pointer which is not either "

                      << "inbounds or in address space 0 may wrap:\n"
@@ -1471,8 +1473,6 @@ std::optional<int64_t> llvm::getPtrStride(PredicatedScalarEvolution &PSE, 
                      << "LAA:   SCEV: " << *AR << "\n"

                      << "LAA:   Added an overflow assumption\n");

    PSE.setNoOverflow(Ptr, SCEVWrapPredicate::IncrementNUSW);

    } else

      return std::nullopt;

  }



  return Stride;