Add -funique-source-file-identifier option.

This option complements -funique-source-file-names and allows the user
to use a different unique identifier than the source file path.

Reviewers: teresajohnson

Reviewed By: teresajohnson

Pull Request: https://github.com/llvm/llvm-project/pull/142901

1 files changed, 6 insertions, 4 deletions

diff --git a/llvm/lib/Transforms/Utils/ModuleUtils.cpp b/llvm/lib/Transforms/Utils/ModuleUtils.cpp
index 10efdd6..596849e 100644
--- a/llvm/lib/Transforms/Utils/ModuleUtils.cpp
+++ b/llvm/lib/Transforms/Utils/ModuleUtils.cpp
@@ -18,6 +18,7 @@
 #include "llvm/IR/IRBuilder.h"
 #include "llvm/IR/MDBuilder.h"
 #include "llvm/IR/Module.h"
+#include "llvm/Support/Casting.h"
 #include "llvm/Support/MD5.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Support/xxhash.h"
@@ -346,10 +347,11 @@ void llvm::filterDeadComdatFunctions(
 std::string llvm::getUniqueModuleId(Module *M) {
   MD5 Md5;
 
-  auto *UniqueSourceFileNames = mdconst::extract_or_null<ConstantInt>(
-      M->getModuleFlag("Unique Source File Names"));
-  if (UniqueSourceFileNames && UniqueSourceFileNames->getZExtValue()) {
-    Md5.update(M->getSourceFileName());
+  auto *UniqueSourceFileIdentifier = dyn_cast_or_null<MDNode>(
+      M->getModuleFlag("Unique Source File Identifier"));
+  if (UniqueSourceFileIdentifier) {
+    Md5.update(
+        cast<MDString>(UniqueSourceFileIdentifier->getOperand(0))->getString());
   } else {
     bool ExportsSymbols = false;
     for (auto &GV : M->global_values()) {