1 files changed, 118 insertions, 0 deletions
diff --git a/contrib/llvm-project/llvm/lib/Transforms/Utils/UniqueInternalLinkageNames.cpp b/contrib/llvm-project/llvm/lib/Transforms/Utils/UniqueInternalLinkageNames.cpp
new file mode 100644
index 000000000000..c57cec6be676
--- /dev/null
+++ b/contrib/llvm-project/llvm/lib/Transforms/Utils/UniqueInternalLinkageNames.cpp
@@ -0,0 +1,118 @@
+//===- UniqueInternalLinkageNames.cpp - Unique Internal Linkage Sym Names -===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements unique naming of internal linkage symbols with option
+// -funique-internal-linkage-symbols.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Transforms/Utils/UniqueInternalLinkageNames.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/IR/DebugInfoMetadata.h"
+#include "llvm/IR/MDBuilder.h"
+#include "llvm/IR/Module.h"
+#include "llvm/InitializePasses.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/MD5.h"
+#include "llvm/Transforms/Utils/ModuleUtils.h"
+
+using namespace llvm;
+
+static bool uniqueifyInternalLinkageNames(Module &M) {
+  llvm::MD5 Md5;
+  Md5.update(M.getSourceFileName());
+  llvm::MD5::MD5Result R;
+  Md5.final(R);
+  SmallString<32> Str;
+  llvm::MD5::stringifyResult(R, Str);
+  // Convert MD5hash to Decimal. Demangler suffixes can either contain numbers
+  // or characters but not both.
+  APInt IntHash = APInt(128, Str.str(), 16);
+  // Prepend "__uniq" before the hash for tools like profilers to understand that
+  // this symbol is of internal linkage type.
+  std::string ModuleNameHash = (Twine(".__uniq.") + Twine(IntHash.toString(10, false))).str();
+  bool Changed = false;
+  MDBuilder MDB(M.getContext());
+
+  // Append the module hash to all internal linkage functions.
+  for (auto &F : M) {
+    if (F.hasInternalLinkage()) {
+      F.setName(F.getName() + ModuleNameHash);
+      F.addFnAttr("sample-profile-suffix-elision-policy", "selected");
+      // Replace linkage names in the debug metadata.
+      if (DISubprogram *SP = F.getSubprogram()) {
+        if (SP->getRawLinkageName()) {
+          auto *Name = MDB.createString(F.getName());
+          SP->replaceRawLinkageName(Name);
+          if (DISubprogram *SPDecl = SP->getDeclaration()) {
+            if (SPDecl->getRawLinkageName())
+              SPDecl->replaceRawLinkageName(Name);
+          }
+        }
+      }
+      Changed = true;
+    }
+  }
+
+  // Append the module hash to all internal linkage globals.
+  for (auto &GV : M.globals()) {
+    if (GV.hasInternalLinkage()) {
+      GV.setName(GV.getName() + ModuleNameHash);
+      Changed = true;
+    }
+  }
+  return Changed;
+}
+
+namespace {
+
+// Legacy pass that provides a name to every anon globals.
+class UniqueInternalLinkageNamesLegacyPass : public ModulePass {
+
+public:
+  /// Pass identification, replacement for typeid
+  static char ID;
+
+  /// Specify pass name for debug output
+  StringRef getPassName() const override {
+    return "Unique Internal Linkage Names";
+  }
+
+  explicit UniqueInternalLinkageNamesLegacyPass() : ModulePass(ID) {
+    initializeUniqueInternalLinkageNamesLegacyPassPass(
+        *PassRegistry::getPassRegistry());
+  }
+
+  bool runOnModule(Module &M) override {
+    return uniqueifyInternalLinkageNames(M);
+  }
+};
+
+char UniqueInternalLinkageNamesLegacyPass::ID = 0;
+} // anonymous namespace
+
+PreservedAnalyses
+UniqueInternalLinkageNamesPass::run(Module &M, ModuleAnalysisManager &AM) {
+  if (!uniqueifyInternalLinkageNames(M))
+    return PreservedAnalyses::all();
+
+  return PreservedAnalyses::none();
+}
+
+INITIALIZE_PASS_BEGIN(UniqueInternalLinkageNamesLegacyPass,
+                      "unique-internal-linkage-names",
+                      "Uniqueify internal linkage names", false, false)
+INITIALIZE_PASS_END(UniqueInternalLinkageNamesLegacyPass,
+                    "unique-internal-linkage-names",
+                    "Uniqueify Internal linkage names", false, false)
+
+namespace llvm {
+ModulePass *createUniqueInternalLinkageNamesPass() {
+  return new UniqueInternalLinkageNamesLegacyPass();
+}
+} // namespace llvm