[llvm] 3b15a7c - [BFI] Use SmallPtrSets. NFCI.

[Benjamin Kramer via llvm-commits]

Author: Benjamin Kramer
Date: 2022-03-11T15:20:57+01:00
New Revision: 3b15a7c042098f2883b6b727ef412685e25f5849

URL: https://github.com/llvm/llvm-project/commit/3b15a7c042098f2883b6b727ef412685e25f5849
DIFF: https://github.com/llvm/llvm-project/commit/3b15a7c042098f2883b6b727ef412685e25f5849.diff

LOG: [BFI] Use SmallPtrSets. NFCI.

Added: 
    

Modified: 
    llvm/include/llvm/Analysis/BlockFrequencyInfoImpl.h

Removed: 
    


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diff  --git a/llvm/include/llvm/Analysis/BlockFrequencyInfoImpl.h b/llvm/include/llvm/Analysis/BlockFrequencyInfoImpl.h
index dc884eddba732..256f1b7881d28 100644
--- a/llvm/include/llvm/Analysis/BlockFrequencyInfoImpl.h
+++ b/llvm/include/llvm/Analysis/BlockFrequencyInfoImpl.h
@@ -20,6 +20,7 @@
 #include "llvm/ADT/GraphTraits.h"
 #include "llvm/ADT/Optional.h"
 #include "llvm/ADT/PostOrderIterator.h"
+#include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/SparseBitVector.h"
 #include "llvm/ADT/Twine.h"
@@ -44,7 +45,6 @@
 #include <list>
 #include <queue>
 #include <string>
-#include <unordered_set>
 #include <utility>
 #include <vector>
 
@@ -1515,7 +1515,7 @@ void BlockFrequencyInfoImpl<BT>::findReachableBlocks(
   // Find all blocks to apply inference on, that is, reachable from the entry
   // along edges with non-zero probablities
   std::queue<const BlockT *> Queue;
-  std::unordered_set<const BlockT *> Reachable;
+  SmallPtrSet<const BlockT *, 8> Reachable;
   const BlockT *Entry = &F->front();
   Queue.push(Entry);
   Reachable.insert(Entry);
@@ -1526,16 +1526,14 @@ void BlockFrequencyInfoImpl<BT>::findReachableBlocks(
       auto EP = BPI->getEdgeProbability(SrcBB, DstBB);
       if (EP.isZero())
         continue;
-      if (Reachable.find(DstBB) == Reachable.end()) {
+      if (Reachable.insert(DstBB).second)
         Queue.push(DstBB);
-        Reachable.insert(DstBB);
-      }
     }
   }
 
   // Find all blocks to apply inference on, that is, backward reachable from
   // the entry along (backward) edges with non-zero probablities
-  std::unordered_set<const BlockT *> InverseReachable;
+  SmallPtrSet<const BlockT *, 8> InverseReachable;
   for (const BlockT &BB : *F) {
     // An exit block is a block without any successors
     bool HasSucc = GraphTraits<const BlockT *>::child_begin(&BB) !=
@@ -1552,10 +1550,8 @@ void BlockFrequencyInfoImpl<BT>::findReachableBlocks(
       auto EP = BPI->getEdgeProbability(DstBB, SrcBB);
       if (EP.isZero())
         continue;
-      if (InverseReachable.find(DstBB) == InverseReachable.end()) {
+      if (InverseReachable.insert(DstBB).second)
         Queue.push(DstBB);
-        InverseReachable.insert(DstBB);
-      }
     }
   }
 
@@ -1580,15 +1576,14 @@ void BlockFrequencyInfoImpl<BT>::initTransitionProbabilities(
   // Find unique successors and corresponding probabilities for every block
   for (size_t Src = 0; Src < NumBlocks; Src++) {
     const BlockT *BB = Blocks[Src];
-    std::unordered_set<const BlockT *> UniqueSuccs;
+    SmallPtrSet<const BlockT *, 2> UniqueSuccs;
     for (const auto SI : children<const BlockT *>(BB)) {
       // Ignore cold blocks
       if (BlockIndex.find(SI) == BlockIndex.end())
         continue;
       // Ignore parallel edges between BB and SI blocks
-      if (UniqueSuccs.find(SI) != UniqueSuccs.end())
+      if (!UniqueSuccs.insert(SI).second)
         continue;
-      UniqueSuccs.insert(SI);
       // Ignore jumps with zero probability
       auto EP = BPI->getEdgeProbability(BB, SI);
       if (EP.isZero())