[llvm-branch-commits] [llvm] 10ddb92 - [SCEV] Use isa<> pattern for testing for CouldNotCompute [NFC]

[Philip Reames via llvm-branch-commits]

Author: Philip Reames
Date: 2020-11-24T18:47:49-08:00
New Revision: 10ddb927c1c3ee6af0436c23f93fe1da6de7b99a

URL: https://github.com/llvm/llvm-project/commit/10ddb927c1c3ee6af0436c23f93fe1da6de7b99a
DIFF: https://github.com/llvm/llvm-project/commit/10ddb927c1c3ee6af0436c23f93fe1da6de7b99a.diff

LOG: [SCEV] Use isa<> pattern for testing for CouldNotCompute [NFC]

Some older code - and code copied from older code - still directly tested against the singelton result of SE::getCouldNotCompute.  Using the isa<SCEVCouldNotCompute> form is both shorter, and more readable.

Added: 
    

Modified: 
    llvm/lib/Analysis/LoopAccessAnalysis.cpp
    llvm/lib/Transforms/Scalar/LoopInterchange.cpp
    llvm/lib/Transforms/Scalar/LoopVersioningLICM.cpp
    llvm/lib/Transforms/Scalar/PlaceSafepoints.cpp
    llvm/lib/Transforms/Utils/ScalarEvolutionExpander.cpp
    llvm/lib/Transforms/Vectorize/LoopVectorize.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Analysis/LoopAccessAnalysis.cpp b/llvm/lib/Analysis/LoopAccessAnalysis.cpp
index 0bffa7dbddec..78f63c63cb40 100644
--- a/llvm/lib/Analysis/LoopAccessAnalysis.cpp
+++ b/llvm/lib/Analysis/LoopAccessAnalysis.cpp
@@ -1803,7 +1803,7 @@ bool LoopAccessInfo::canAnalyzeLoop() {
 
   // ScalarEvolution needs to be able to find the exit count.
   const SCEV *ExitCount = PSE->getBackedgeTakenCount();
-  if (ExitCount == PSE->getSE()->getCouldNotCompute()) {
+  if (isa<SCEVCouldNotCompute>(ExitCount)) {
     recordAnalysis("CantComputeNumberOfIterations")
         << "could not determine number of loop iterations";
     LLVM_DEBUG(dbgs() << "LAA: SCEV could not compute the loop exit count.\n");

diff  --git a/llvm/lib/Transforms/Scalar/LoopInterchange.cpp b/llvm/lib/Transforms/Scalar/LoopInterchange.cpp
index 81b7c3a8338a..f676ffc18e2d 100644
--- a/llvm/lib/Transforms/Scalar/LoopInterchange.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopInterchange.cpp
@@ -452,7 +452,7 @@ struct LoopInterchange {
   bool isComputableLoopNest(LoopVector LoopList) {
     for (Loop *L : LoopList) {
       const SCEV *ExitCountOuter = SE->getBackedgeTakenCount(L);
-      if (ExitCountOuter == SE->getCouldNotCompute()) {
+      if (isa<SCEVCouldNotCompute>(ExitCountOuter)) {
         LLVM_DEBUG(dbgs() << "Couldn't compute backedge count\n");
         return false;
       }

diff  --git a/llvm/lib/Transforms/Scalar/LoopVersioningLICM.cpp b/llvm/lib/Transforms/Scalar/LoopVersioningLICM.cpp
index 3d0ce87047ad..2ff1e8480749 100644
--- a/llvm/lib/Transforms/Scalar/LoopVersioningLICM.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopVersioningLICM.cpp
@@ -267,7 +267,7 @@ bool LoopVersioningLICM::legalLoopStructure() {
   // We need to be able to compute the loop trip count in order
   // to generate the bound checks.
   const SCEV *ExitCount = SE->getBackedgeTakenCount(CurLoop);
-  if (ExitCount == SE->getCouldNotCompute()) {
+  if (isa<SCEVCouldNotCompute>(ExitCount)) {
     LLVM_DEBUG(dbgs() << "    loop does not has trip count\n");
     return false;
   }

diff  --git a/llvm/lib/Transforms/Scalar/PlaceSafepoints.cpp b/llvm/lib/Transforms/Scalar/PlaceSafepoints.cpp
index 4553b23532f2..ca114581a515 100644
--- a/llvm/lib/Transforms/Scalar/PlaceSafepoints.cpp
+++ b/llvm/lib/Transforms/Scalar/PlaceSafepoints.cpp
@@ -243,7 +243,7 @@ static bool mustBeFiniteCountedLoop(Loop *L, ScalarEvolution *SE,
                                     BasicBlock *Pred) {
   // A conservative bound on the loop as a whole.
   const SCEV *MaxTrips = SE->getConstantMaxBackedgeTakenCount(L);
-  if (MaxTrips != SE->getCouldNotCompute() &&
+  if (!isa<SCEVCouldNotCompute>(MaxTrips) &&
       SE->getUnsignedRange(MaxTrips).getUnsignedMax().isIntN(
           CountedLoopTripWidth))
     return true;
@@ -255,7 +255,7 @@ static bool mustBeFiniteCountedLoop(Loop *L, ScalarEvolution *SE,
     // This returns an exact expression only.  TODO: We really only need an
     // upper bound here, but SE doesn't expose that.
     const SCEV *MaxExec = SE->getExitCount(L, Pred);
-    if (MaxExec != SE->getCouldNotCompute() &&
+    if (!isa<SCEVCouldNotCompute>(MaxExec) &&
         SE->getUnsignedRange(MaxExec).getUnsignedMax().isIntN(
             CountedLoopTripWidth))
         return true;

diff  --git a/llvm/lib/Transforms/Utils/ScalarEvolutionExpander.cpp b/llvm/lib/Transforms/Utils/ScalarEvolutionExpander.cpp
index 877495be2dcd..c7e37fe0d1b3 100644
--- a/llvm/lib/Transforms/Utils/ScalarEvolutionExpander.cpp
+++ b/llvm/lib/Transforms/Utils/ScalarEvolutionExpander.cpp
@@ -2468,7 +2468,7 @@ Value *SCEVExpander::generateOverflowCheck(const SCEVAddRecExpr *AR,
   const SCEV *ExitCount =
       SE.getPredicatedBackedgeTakenCount(AR->getLoop(), Pred);
 
-  assert(ExitCount != SE.getCouldNotCompute() && "Invalid loop count");
+  assert(!isa<SCEVCouldNotCompute>(ExitCount) && "Invalid loop count");
 
   const SCEV *Step = AR->getStepRecurrence(SE);
   const SCEV *Start = AR->getStart();

diff  --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index af314ae4b27b..e29a0a8bd666 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -2728,7 +2728,7 @@ Value *InnerLoopVectorizer::getOrCreateTripCount(Loop *L) {
   // Find the loop boundaries.
   ScalarEvolution *SE = PSE.getSE();
   const SCEV *BackedgeTakenCount = PSE.getBackedgeTakenCount();
-  assert(BackedgeTakenCount != SE->getCouldNotCompute() &&
+  assert(!isa<SCEVCouldNotCompute>(BackedgeTakenCount) &&
          "Invalid loop count");
 
   Type *IdxTy = Legal->getWidestInductionType();
@@ -8274,7 +8274,7 @@ static bool processLoopInVPlanNativePath(
     OptimizationRemarkEmitter *ORE, BlockFrequencyInfo *BFI,
     ProfileSummaryInfo *PSI, LoopVectorizeHints &Hints) {
 
-  if (PSE.getBackedgeTakenCount() == PSE.getSE()->getCouldNotCompute()) {
+  if (isa<SCEVCouldNotCompute>(PSE.getBackedgeTakenCount())) {
     LLVM_DEBUG(dbgs() << "LV: cannot compute the outer-loop trip count\n");
     return false;
   }