1 files changed, 3 insertions, 10 deletions
diff --git a/src/passes/SignatureRefining.cpp b/src/passes/SignatureRefining.cpp
index 132079b76..15b89b2a7 100644
--- a/src/passes/SignatureRefining.cpp
+++ b/src/passes/SignatureRefining.cpp
@@ -161,7 +161,7 @@ struct SignatureRefining : public Pass {
 
       auto updateLUBs = [&](const ExpressionList& operands) {
         for (Index i = 0; i < numParams; i++) {
-          paramLUBs[i].noteUpdatableExpression(operands[i]);
+          paramLUBs[i].note(operands[i]->type);
         }
       };
 
@@ -178,7 +178,7 @@ struct SignatureRefining : public Pass {
         if (!lub.noted()) {
           break;
         }
-        newParamsTypes.push_back(lub.getBestPossible());
+        newParamsTypes.push_back(lub.getLUB());
       }
       Type newParams;
       if (newParamsTypes.size() < numParams) {
@@ -197,7 +197,7 @@ struct SignatureRefining : public Pass {
         // value, or it can return a value but traps instead etc.).
         newResults = func->getResults();
       } else {
-        newResults = resultsLUB.getBestPossible();
+        newResults = resultsLUB.getLUB();
       }
 
       if (newParams == func->getParams() && newResults == func->getResults()) {
@@ -207,14 +207,7 @@ struct SignatureRefining : public Pass {
       // We found an improvement!
       newSignatures[type] = Signature(newParams, newResults);
 
-      // Update nulls as necessary, now that we are changing things.
-      if (newParams != func->getParams()) {
-        for (auto& lub : paramLUBs) {
-          lub.updateNulls();
-        }
-      }
       if (newResults != func->getResults()) {
-        resultsLUB.updateNulls();
         refinedResults = true;
 
         // Update the types of calls using the signature.