1 files changed, 5 insertions, 0 deletions
diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp
index 8a0695c325d..58f6cd187dd 100644
--- a/llvm/lib/Analysis/ValueTracking.cpp
+++ b/llvm/lib/Analysis/ValueTracking.cpp
@@ -3477,6 +3477,11 @@ bool llvm::propagatesFullPoison(const Instruction *I) {
       return false;
     }
 
+    case Instruction::ICmp:
+      // Comparing poison with any value yields poison.  This is why, for
+      // instance, x s< (x +nsw 1) can be folded to true.
+      return true;
+
     case Instruction::GetElementPtr:
       // A GEP implicitly represents a sequence of additions, subtractions,
       // truncations, sign extensions and multiplications. The multiplications