[Mlir-commits] [mlir] Improve MLIR attribute get() method efficiency when complex members are involved (PR #68067)

[Mehdi Amini]

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@@ -459,4 +461,25 @@ TEST(SubElementTest, Nested) {
             ArrayRef<Attribute>(
                 {strAttr, trueAttr, falseAttr, boolArrayAttr, dictAttr}));
 }
+
+// Test how many times we call copy-ctor when building an attribute.
+TEST(CopyCountAttr, CopyCount) {
+  MLIRContext context;
+  context.loadDialect<test::TestDialect>();
+
+  test::CopyCount::counter = 0;
+  test::CopyCount copyCount("hello");
+  test::TestCopyCountAttr::get(&context, std::move(copyCount));
+  int counter1 = test::CopyCount::counter;
+  test::CopyCount::counter = 0;
+  test::TestCopyCountAttr::get(&context, std::move(copyCount));
+#ifndef NDEBUG
+  EXPECT_EQ(counter1, 1);
+  EXPECT_EQ(test::CopyCount::counter, 1);
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joker-eph wrote:

There is a verifier when assertion are enabled and a copy is necessary...

https://github.com/llvm/llvm-project/pull/68067