[llvm] 68aa6ac - [SLP] NFC. Remove redundant computation in getReorderingData. (#117295)

[via llvm-commits]

Author: Han-Kuan Chen
Date: 2024-11-22T18:54:41+08:00
New Revision: 68aa6ac58c2bd59cac15417e7d8356ef8382dabd

URL: https://github.com/llvm/llvm-project/commit/68aa6ac58c2bd59cac15417e7d8356ef8382dabd
DIFF: https://github.com/llvm/llvm-project/commit/68aa6ac58c2bd59cac15417e7d8356ef8382dabd.diff

LOG: [SLP] NFC. Remove redundant computation in getReorderingData. (#117295)

Added: 
    

Modified: 
    llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp

Removed: 
    


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diff  --git a/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp b/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
index 47b9f70b6fa026..c445ee8ae22015 100644
--- a/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
+++ b/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
@@ -5626,18 +5626,12 @@ BoUpSLP::getReorderingData(const TreeEntry &TE, bool TopToBottom) {
       }
       return false;
     };
-    SmallDenseMap<unsigned, unsigned, 16> PhiToId;
-    SmallVector<unsigned> Phis(TE.Scalars.size());
+    OrdersType Phis(TE.Scalars.size());
     std::iota(Phis.begin(), Phis.end(), 0);
-    OrdersType ResOrder(TE.Scalars.size());
-    for (unsigned Id = 0, Sz = TE.Scalars.size(); Id < Sz; ++Id)
-      PhiToId[Id] = Id;
     stable_sort(Phis, PHICompare);
-    for (unsigned Id = 0, Sz = Phis.size(); Id < Sz; ++Id)
-      ResOrder[Id] = PhiToId[Phis[Id]];
-    if (isIdentityOrder(ResOrder))
+    if (isIdentityOrder(Phis))
       return std::nullopt; // No need to reorder.
-    return std::move(ResOrder);
+    return std::move(Phis);
   }
   if (TE.isGather() && !TE.isAltShuffle() && allSameType(TE.Scalars)) {
     // TODO: add analysis of other gather nodes with extractelement