1 files changed, 62 insertions, 0 deletions
diff --git a/llvm/lib/Transforms/Utils/InstructionNamer.cpp b/llvm/lib/Transforms/Utils/InstructionNamer.cpp
new file mode 100644
index 0000000000000..6c4fc1ceb9913
--- /dev/null
+++ b/llvm/lib/Transforms/Utils/InstructionNamer.cpp
@@ -0,0 +1,62 @@
+//===- InstructionNamer.cpp - Give anonymous instructions 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 is a little utility pass that gives instructions names, this is mostly
+// useful when diffing the effect of an optimization because deleting an
+// unnamed instruction can change all other instruction numbering, making the
+// diff very noisy.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/IR/Function.h"
+#include "llvm/IR/Type.h"
+#include "llvm/Pass.h"
+#include "llvm/Transforms/Utils.h"
+using namespace llvm;
+
+namespace {
+  struct InstNamer : public FunctionPass {
+    static char ID; // Pass identification, replacement for typeid
+    InstNamer() : FunctionPass(ID) {
+      initializeInstNamerPass(*PassRegistry::getPassRegistry());
+    }
+
+    void getAnalysisUsage(AnalysisUsage &Info) const override {
+      Info.setPreservesAll();
+    }
+
+    bool runOnFunction(Function &F) override {
+      for (auto &Arg : F.args())
+        if (!Arg.hasName())
+          Arg.setName("arg");
+
+      for (BasicBlock &BB : F) {
+        if (!BB.hasName())
+          BB.setName("bb");
+
+        for (Instruction &I : BB)
+          if (!I.hasName() && !I.getType()->isVoidTy())
+            I.setName("tmp");
+      }
+      return true;
+    }
+  };
+
+  char InstNamer::ID = 0;
+}
+
+INITIALIZE_PASS(InstNamer, "instnamer",
+                "Assign names to anonymous instructions", false, false)
+char &llvm::InstructionNamerID = InstNamer::ID;
+//===----------------------------------------------------------------------===//
+//
+// InstructionNamer - Give any unnamed non-void instructions "tmp" names.
+//
+FunctionPass *llvm::createInstructionNamerPass() {
+  return new InstNamer();
+}