1 files changed, 43 insertions, 33 deletions

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
index dfa922b7480..ad2bd1841f1 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
@@ -1532,50 +1532,60 @@ Instruction *InstCombiner::foldICmpAndConstConst(ICmpInst &Cmp,
   if (Instruction *I = foldICmpAndShift(Cmp, And, C1))
     return I;
 
+  // FIXME: This check restricts all folds under here to scalar types.
+  ConstantInt *RHS = dyn_cast<ConstantInt>(Cmp.getOperand(1));
+  if (!RHS)
+    return nullptr;
+
   // (icmp pred (and (or (lshr A, B), A), 1), 0) -->
   // (icmp pred (and A, (or (shl 1, B), 1), 0))
   //
   // iff pred isn't signed
-  if (!Cmp.isSigned() && *C1 == 0 && match(And->getOperand(1), m_One())) {
-    Constant *One = cast<Constant>(And->getOperand(1));
-    Value *Or = And->getOperand(0);
+  {
     Value *A, *B, *LShr;
-    if (match(Or, m_Or(m_Value(LShr), m_Value(A))) &&
-        match(LShr, m_LShr(m_Specific(A), m_Value(B)))) {
-      unsigned UsesRemoved = 0;
-      if (And->hasOneUse())
-        ++UsesRemoved;
-      if (Or->hasOneUse())
-        ++UsesRemoved;
-      if (LShr->hasOneUse())
-        ++UsesRemoved;
-
-      // Compute A & ((1 << B) | 1)
-      Value *NewOr = nullptr;
-      if (auto *C = dyn_cast<Constant>(B)) {
-        if (UsesRemoved >= 1)
-          NewOr = ConstantExpr::getOr(ConstantExpr::getNUWShl(One, C), One);
-      } else {
-        if (UsesRemoved >= 3)
-          NewOr = Builder->CreateOr(Builder->CreateShl(One, B, LShr->getName(),
+    if (!Cmp.isSigned() && *C1 == 0) {
+      if (match(And->getOperand(1), m_One())) {
+        Constant *One = cast<Constant>(And->getOperand(1));
+        Value *Or = And->getOperand(0);
+        if (match(Or, m_Or(m_Value(LShr), m_Value(A))) &&
+            match(LShr, m_LShr(m_Specific(A), m_Value(B)))) {
+          unsigned UsesRemoved = 0;
+          if (And->hasOneUse())
+            ++UsesRemoved;
+          if (Or->hasOneUse())
+            ++UsesRemoved;
+          if (LShr->hasOneUse())
+            ++UsesRemoved;
+          Value *NewOr = nullptr;
+          // Compute A & ((1 << B) | 1)
+          if (auto *C = dyn_cast<Constant>(B)) {
+            if (UsesRemoved >= 1)
+              NewOr = ConstantExpr::getOr(ConstantExpr::getNUWShl(One, C), One);
+          } else {
+            if (UsesRemoved >= 3)
+              NewOr =
+                  Builder->CreateOr(Builder->CreateShl(One, B, LShr->getName(),
                                                        /*HasNUW=*/true),
                                     One, Or->getName());
-      }
-      if (NewOr) {
-        Value *NewAnd = Builder->CreateAnd(A, NewOr, And->getName());
-        Cmp.setOperand(0, NewAnd);
-        return &Cmp;
+          }
+          if (NewOr) {
+            Value *NewAnd = Builder->CreateAnd(A, NewOr, And->getName());
+            Cmp.setOperand(0, NewAnd);
+            return &Cmp;
+          }
+        }
       }
     }
   }
 
-  // (X & C2) > C1 --> (X & C2) != 0, if any bit set in (X & C2) will produce a
-  // result greater than C1.
-  unsigned NumTZ = C2->countTrailingZeros();
-  if (Cmp.getPredicate() == ICmpInst::ICMP_UGT && NumTZ < C2->getBitWidth() &&
-      APInt::getOneBitSet(C2->getBitWidth(), NumTZ).ugt(*C1)) {
-    Constant *Zero = Constant::getNullValue(And->getType());
-    return new ICmpInst(ICmpInst::ICMP_NE, And, Zero);
+  // Replace ((X & C2) > C1) with ((X & C2) != 0), if any bit set in (X & C2)
+  // will produce a result greater than C1.
+  if (Cmp.getPredicate() == ICmpInst::ICMP_UGT) {
+    unsigned NTZ = C2->countTrailingZeros();
+    if ((NTZ < C2->getBitWidth()) &&
+        APInt::getOneBitSet(C2->getBitWidth(), NTZ).ugt(*C1))
+      return new ICmpInst(ICmpInst::ICMP_NE, And,
+                          Constant::getNullValue(RHS->getType()));
   }
 
   return nullptr;