1 files changed, 17 insertions, 0 deletions
diff --git a/llvm/lib/Analysis/ConstantFolding.cpp b/llvm/lib/Analysis/ConstantFolding.cpp
index 5febe91..1d4272a 100644
--- a/llvm/lib/Analysis/ConstantFolding.cpp
+++ b/llvm/lib/Analysis/ConstantFolding.cpp
@@ -1504,6 +1504,8 @@ bool llvm::canConstantFoldCallTo(const CallBase *Call, const Function *F) {
   case Intrinsic::smin:
   case Intrinsic::umax:
   case Intrinsic::umin:
+  case Intrinsic::scmp:
+  case Intrinsic::ucmp:
   case Intrinsic::sadd_with_overflow:
   case Intrinsic::uadd_with_overflow:
   case Intrinsic::ssub_with_overflow:
@@ -2773,6 +2775,21 @@ static Constant *ConstantFoldIntrinsicCall2(Intrinsic::ID IntrinsicID, Type *Ty,
                   ? *C0
                   : *C1);
 
+    case Intrinsic::scmp:
+    case Intrinsic::ucmp:
+      if (isa<PoisonValue>(Operands[0]) || isa<PoisonValue>(Operands[1]))
+        return PoisonValue::get(Ty);
+
+      if (!C0 || !C1)
+        return ConstantInt::get(Ty, 0);
+
+      int Res;
+      if (IntrinsicID == Intrinsic::scmp)
+        Res = C0->sgt(*C1) ? 1 : C0->slt(*C1) ? -1 : 0;
+      else
+        Res = C0->ugt(*C1) ? 1 : C0->ult(*C1) ? -1 : 0;
+      return ConstantInt::get(Ty, Res, /*IsSigned=*/true);
+
     case Intrinsic::usub_with_overflow:
     case Intrinsic::ssub_with_overflow:
       // X - undef -> { 0, false }