[ThinLTO][NFC] Add Module Name Debug Print when Generating Module Maps

[qiongsiwu]

When computing the module maps, ThinLTOCodeGenerator asserts if it sees duplicating module names. This PR adds a debug print, so that the list of modules already added can be printed. With this information, one can identify which modules are causing the duplication.

[llvmbot]

@llvm/pr-subscribers-lto

Changes

When computing the module maps, ThinLTOCodeGenerator asserts if it sees a duplicating module name. This PR adds debug print, so that the list of modules already added can be printed. With this information, one can identify which module is causing the duplication.

---

Full diff: https://github.com/llvm/llvm-project/pull/67820.diff

1 Files Affected:

• (modified) llvm/lib/LTO/ThinLTOCodeGenerator.cpp (+1)

diff --git a/llvm/lib/LTO/ThinLTOCodeGenerator.cpp b/llvm/lib/LTO/ThinLTOCodeGenerator.cpp
index acff1e2cf3b33b0..443439b71e7566c 100644
--- a/llvm/lib/LTO/ThinLTOCodeGenerator.cpp
+++ b/llvm/lib/LTO/ThinLTOCodeGenerator.cpp
@@ -151,6 +151,7 @@ static StringMap<lto::InputFile *>
 generateModuleMap(std::vector<std::unique_ptr<lto::InputFile>> &Modules) {
   StringMap<lto::InputFile *> ModuleMap;
   for (auto &M : Modules) {
+    LLVM_DEBUG(dbgs() << "Adding module " << M->getName() << " to ModuleMap\n");
     assert(!ModuleMap.contains(M->getName()) &&
            "Expect unique Buffer Identifier");
     ModuleMap[M->getName()] = M.get();

[w2yehia]

LGTM.