1 files changed, 25 insertions, 0 deletions
diff --git a/llvm/lib/CodeGen/GlobalISel/Utils.cpp b/llvm/lib/CodeGen/GlobalISel/Utils.cpp
index ed168a6188b..deccdc6c750 100644
--- a/llvm/lib/CodeGen/GlobalISel/Utils.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/Utils.cpp
@@ -367,6 +367,31 @@ Optional<APInt> llvm::ConstantFoldBinOp(unsigned Opcode, const unsigned Op1,
   return None;
 }
 
+bool llvm::isKnownNeverNaN(Register Val, const MachineRegisterInfo &MRI,
+                           bool SNaN) {
+  const MachineInstr *DefMI = MRI.getVRegDef(Val);
+  if (!DefMI)
+    return false;
+
+  if (DefMI->getFlag(MachineInstr::FmNoNans))
+    return true;
+
+  if (SNaN) {
+    // FP operations quiet. For now, just handle the ones inserted during
+    // legalization.
+    switch (DefMI->getOpcode()) {
+    case TargetOpcode::G_FPEXT:
+    case TargetOpcode::G_FPTRUNC:
+    case TargetOpcode::G_FCANONICALIZE:
+      return true;
+    default:
+      return false;
+    }
+  }
+
+  return false;
+}
+
 void llvm::getSelectionDAGFallbackAnalysisUsage(AnalysisUsage &AU) {
   AU.addPreserved<StackProtector>();
 }