[llvm] Introduce LDBG_OS() macro as a variant of LDBG() (PR #157194)

[Andrzej Warzyński via llvm-commits]

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@@ -128,6 +128,131 @@ TEST(DebugLogTest, DestructorPrefix) {
   // After destructors, nothing should have been printed.
   EXPECT_EQ(os.str(), "");
 }
+
+TEST(DebugLogTest, LDBG_MACROS) {
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banach-space wrote:

I would split this into multiple smaller test functions. That shouldn't impact test coverage, but would definitely make triaging any potential failures easier :)

https://github.com/llvm/llvm-project/pull/157194