diff --git a/src/Futhark/IR/Mem/IxFun.hs b/src/Futhark/IR/Mem/IxFun.hs
index d6fba0972b..0bdb37c53f 100644
--- a/src/Futhark/IR/Mem/IxFun.hs
+++ b/src/Futhark/IR/Mem/IxFun.hs
@@ -23,7 +23,6 @@ module Futhark.IR.Mem.IxFun
     substituteInLMAD,
     existentialize,
     closeEnough,
-    permuteInv,
     disjoint,
     disjoint2,
     disjoint3,
diff --git a/src/Futhark/IR/Mem/LMAD.hs b/src/Futhark/IR/Mem/LMAD.hs
index 55c0f0d5e9..78da47a1bd 100644
--- a/src/Futhark/IR/Mem/LMAD.hs
+++ b/src/Futhark/IR/Mem/LMAD.hs
@@ -17,7 +17,6 @@ module Futhark.IR.Mem.LMAD
     shape,
     rank,
     substituteInLMAD,
-    permuteInv,
     disjoint,
     disjoint2,
     disjoint3,
diff --git a/src/Futhark/Optimise/ArrayShortCircuiting/TopdownAnalysis.hs b/src/Futhark/Optimise/ArrayShortCircuiting/TopdownAnalysis.hs
index c6de75d434..abc12b7c90 100644
--- a/src/Futhark/Optimise/ArrayShortCircuiting/TopdownAnalysis.hs
+++ b/src/Futhark/Optimise/ArrayShortCircuiting/TopdownAnalysis.hs
@@ -110,8 +110,7 @@ getInvAliasFromExp (BasicOp (SubExp (Var _))) = Just id
 getInvAliasFromExp (BasicOp (Opaque _ (Var _))) = Just id
 getInvAliasFromExp (BasicOp Update {}) = Just id
 getInvAliasFromExp (BasicOp (Rearrange perm _)) =
-  let perm' = IxFun.permuteInv perm [0 .. length perm - 1]
-   in Just (`IxFun.permute` perm')
+  Just (`IxFun.permute` rearrangeInverse perm)
 getInvAliasFromExp _ = Nothing
 
 class TopDownHelper inner where