[llvm] [IRSim] Avoid repeated hash lookups (NFC) (PR #108483)

[Kazu Hirata via llvm-commits]

https://github.com/kazutakahirata created https://github.com/llvm/llvm-project/pull/108483

None

>From 8431c876866a7e1d3e468eb8670b9ef9ea8bfd9c Mon Sep 17 00:00:00 2001
From: Kazu Hirata <kazu at google.com>
Date: Thu, 12 Sep 2024 00:57:33 -0700
Subject: [PATCH] [IRSim] Avoid repeated hash lookups (NFC)

---
 llvm/lib/Analysis/IRSimilarityIdentifier.cpp | 12 ++----------
 1 file changed, 2 insertions(+), 10 deletions(-)

diff --git a/llvm/lib/Analysis/IRSimilarityIdentifier.cpp b/llvm/lib/Analysis/IRSimilarityIdentifier.cpp
index 41815c633fdf2a..42e986e6179dd3 100644
--- a/llvm/lib/Analysis/IRSimilarityIdentifier.cpp
+++ b/llvm/lib/Analysis/IRSimilarityIdentifier.cpp
@@ -1420,16 +1420,8 @@ void IRSimilarityIdentifier::findCandidates(
         // IRSimilarityCandidates that include that instruction.
         for (IRSimilarityCandidate &IRCand : SimilarityCandidates->back()) {
           for (unsigned Idx = IRCand.getStartIdx(), Edx = IRCand.getEndIdx();
-               Idx <= Edx; ++Idx) {
-            DenseMap<unsigned, DenseSet<IRSimilarityCandidate *>>::iterator
-                IdIt;
-            IdIt = IndexToIncludedCand.find(Idx);
-            bool Inserted = false;
-            if (IdIt == IndexToIncludedCand.end())
-              std::tie(IdIt, Inserted) = IndexToIncludedCand.insert(
-                  std::make_pair(Idx, DenseSet<IRSimilarityCandidate *>()));
-            IdIt->second.insert(&IRCand);
-          }
+               Idx <= Edx; ++Idx)
+            IndexToIncludedCand[Idx].insert(&IRCand);
           // Add mapping of candidate to the overall similarity group number.
           CandToGroup.insert(
               std::make_pair(&IRCand, SimilarityCandidates->size() - 1));