[llvm] [DebugInfo] getMergedLocation: match scopes based on their location (PR #132286)

[Stephen Tozer via llvm-commits]

================
@@ -975,6 +1025,162 @@ TEST_F(DILocationTest, Merge) {
     EXPECT_EQ(N, M->getScope());
   }
 
+  {
+    // Different files, same line numbers, same subprogram.
+    auto *F1 = DIFile::getDistinct(Context, "file1.c", "/path/to/dir");
+    auto *F2 = DIFile::getDistinct(Context, "file2.c", "/path/to/dir");
+    DISubprogram *N = getSubprogram(F1);
+    auto *LBF = DILexicalBlockFile::get(Context, N, F2, 0);
+    auto *A = DILocation::get(Context, 1, 6, N);
+    auto *B = DILocation::get(Context, 1, 6, LBF);
+    auto *M = DILocation::getMergedLocation(A, B);
+    EXPECT_EQ(0u, M->getLine());
+    EXPECT_EQ(0u, M->getColumn());
+    EXPECT_EQ(N, M->getScope());
+  }
+
+  {
+    // Different files, same line numbers.
+    auto *F1 = DIFile::getDistinct(Context, "file1.c", "/path/to/dir");
+    auto *F2 = DIFile::getDistinct(Context, "file2.c", "/path/to/dir");
+    DISubprogram *N = getSubprogram(F1);
+    auto *LB = DILexicalBlock::getDistinct(Context, N, F1, 4, 9);
+    auto *LBF = DILexicalBlockFile::get(Context, LB, F2, 0);
+    auto *A = DILocation::get(Context, 1, 6, LB);
+    auto *B = DILocation::get(Context, 1, 6, LBF);
+    auto *M = DILocation::getMergedLocation(A, B);
+    EXPECT_EQ(4u, M->getLine());
+    EXPECT_EQ(9u, M->getColumn());
+    EXPECT_EQ(LB, M->getScope());
+  }
+
+  {
+    // Different files, same line numbers,
+    // both locations have DILexicalBlockFile scopes.
+    auto *F1 = DIFile::getDistinct(Context, "file1.c", "/path/to/dir");
+    auto *F2 = DIFile::getDistinct(Context, "file2.c", "/path/to/dir");
+    auto *F3 = DIFile::getDistinct(Context, "file3.c", "/path/to/dir");
+    DISubprogram *N = getSubprogram(F1);
+    auto *LB = DILexicalBlock::getDistinct(Context, N, F1, 4, 9);
+    auto *LBF1 = DILexicalBlockFile::get(Context, LB, F2, 0);
+    auto *LBF2 = DILexicalBlockFile::get(Context, LB, F3, 0);
+    auto *A = DILocation::get(Context, 1, 6, LBF1);
+    auto *B = DILocation::get(Context, 1, 6, LBF2);
+    auto *M = DILocation::getMergedLocation(A, B);
+    EXPECT_EQ(4u, M->getLine());
+    EXPECT_EQ(9u, M->getColumn());
+    EXPECT_EQ(LB, M->getScope());
+  }
+
+  {
+    // Same file, same line numbers, but different LBF objects.
+    // both locations have DILexicalBlockFile scope.
+    auto *F1 = DIFile::getDistinct(Context, "file1.c", "/path/to/dir");
+    DISubprogram *N = getSubprogram(F1);
+    auto *LB1 = DILexicalBlock::getDistinct(Context, N, F1, 4, 9);
+    auto *LB2 = DILexicalBlock::getDistinct(Context, N, F1, 5, 9);
+    auto *F2 = DIFile::getDistinct(Context, "file2.c", "/path/to/dir");
+    auto *LBF1 = DILexicalBlockFile::get(Context, LB1, F2, 0);
+    auto *LBF2 = DILexicalBlockFile::get(Context, LB2, F2, 0);
+    auto *A = DILocation::get(Context, 1, 6, LBF1);
+    auto *B = DILocation::get(Context, 1, 6, LBF2);
+    llvm::errs() << "Check\n";
+    auto *M = DILocation::getMergedLocation(A, B);
+    M->dump();
+    M->getScope()->dump();
+    LBF1->dump();
----------------
SLTozer wrote:

Looks like some debug dumps left hanging around.

https://github.com/llvm/llvm-project/pull/132286