[llvm] [MachineOutliner] Leaf Descendants (PR #90275)

[Kyungwoo Lee via llvm-commits]

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@@ -140,4 +140,138 @@ TEST(SuffixTreeTest, TestExclusion) {
   }
 }
 
+// Tests that the SuffixTree is able to find the following substrings:
+// {1, 1} at indices 0, 1, 2, 3, and 4;
+// {1, 1, 1} at indices 0, 1, 2, and 3;
+// {1, 1, 1, 1}  at indices 0, 1, and 2; and
+// {1, 1, 1, 1, 1} at indices 0 and 1.
+//
+// This is a FIX to the Test TestSingleCharacterRepeat
+TEST(SuffixTreeTest, TestSingleCharacterRepeatWithLeafDescendants) {
+  std::vector<unsigned> RepeatedRepetitionData = {1, 1, 1, 1, 1, 1, 2};
+  std::vector<unsigned>::iterator RRDIt, RRDIt2;
+  SuffixTree ST(RepeatedRepetitionData, true);
+  std::vector<SuffixTree::RepeatedSubstring> SubStrings;
+  for (auto It = ST.begin(); It != ST.end(); It++)
+    SubStrings.push_back(*It);
+  EXPECT_EQ(SubStrings.size(), 4u);
+  for (SuffixTree::RepeatedSubstring &RS : SubStrings) {
+    EXPECT_EQ(RS.StartIndices.size(),
+              RepeatedRepetitionData.size() - RS.Length);
+    for (unsigned StartIdx : SubStrings[0].StartIndices) {
+      RRDIt = RRDIt2 = RepeatedRepetitionData.begin();
+      std::advance(RRDIt, StartIdx);
+      std::advance(RRDIt2, StartIdx + SubStrings[0].Length);
+      ASSERT_TRUE(
+          all_of(make_range<std::vector<unsigned>::iterator>(RRDIt, RRDIt2),
+                 [](unsigned Elt) { return Elt == 1; }));
+    }
+  }
+}
+
+// Tests that the SuffixTree is able to find three substrings
+// {1, 2, 3} at indices 6 and 10;
+// {2, 3} at indices 7 and 11; and
+// {1, 2} at indicies 0 and 3.
+//
+// FIXME: {1, 2} has indices 6 and 10 missing as it is a substring of {1, 2, 3}
+// See Test TestSubstringRepeatsWithLeafDescendants for the FIX
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kyulee-com wrote:

I think you can delete this line as the fix test just follows it.
If you want to keep this line, I'd add a similar line for `TestSingleCharacterRepeat` referring to `TestSingleCharacterRepeatWithLeafDescendants`. 

https://github.com/llvm/llvm-project/pull/90275