Merge pull request #37 from sampsyo/modernize

Modernize for LLVM 17

Author: sampsyo

CMakeLists.txt

@@ -1,12 +1,22 @@
-cmake_minimum_required(VERSION 3.1)
+cmake_minimum_required(VERSION 3.6)
 project(Skeleton)
 
-# support C++14 features used by LLVM 10.0.0
-set(CMAKE_CXX_STANDARD 14)
+# LLVM uses C++17.
+set(CMAKE_CXX_STANDARD 17)
 
+# Load LLVMConfig.cmake. If this fails, consider setting `LLVM_DIR` to point
+# to your LLVM installation's `lib/cmake/llvm` directory.
 find_package(LLVM REQUIRED CONFIG)
+
+# Include the part of LLVM's CMake libraries that defines
+# `add_llvm_pass_plugin`.
+include(AddLLVM)
+
+# Use LLVM's preprocessor definitions, include directories, and library search
+# paths.
 add_definitions(${LLVM_DEFINITIONS})
 include_directories(${LLVM_INCLUDE_DIRS})
 link_directories(${LLVM_LIBRARY_DIRS})
 
-add_subdirectory(skeleton)  # Use your pass name here.
+# Our pass lives in this subdirectory.
+add_subdirectory(skeleton)

README.md

@@ -1,7 +1,7 @@
 # llvm-pass-skeleton
 
 A completely useless LLVM pass.
-It's for LLVM 14.
+It's for LLVM 17.
 
 Build:
 
@@ -14,4 +14,4 @@ Build:
 
 Run:
 
-    $ clang -flegacy-pass-manager -Xclang -load -Xclang build/skeleton/libSkeletonPass.* something.c
+    $ clang -fpass-plugin=`ls build/skeleton/SkeletonPass.*` something.c

skeleton/CMakeLists.txt

@@ -1,21 +1,4 @@
-add_library(SkeletonPass MODULE
+add_llvm_pass_plugin(SkeletonPass
     # List your source files here.
     Skeleton.cpp
 )
-
-# Use C++11 to compile our pass (i.e., supply -std=c++11).
-target_compile_features(SkeletonPass PRIVATE cxx_range_for cxx_auto_type)
-
-# LLVM is (typically) built with no C++ RTTI. We need to match that;
-# otherwise, we'll get linker errors about missing RTTI data.
-set_target_properties(SkeletonPass PROPERTIES
-    COMPILE_FLAGS "-fno-rtti"
-)
-
-# Get proper shared-library behavior (where symbols are not necessarily
-# resolved when the shared library is linked) on OS X.
-if(APPLE)
-    set_target_properties(SkeletonPass PROPERTIES
-        LINK_FLAGS "-undefined dynamic_lookup"
-    )
-endif(APPLE)

skeleton/Skeleton.cpp

@@ -1,30 +1,34 @@
 #include "llvm/Pass.h"
-#include "llvm/IR/Function.h"
+#include "llvm/Passes/PassBuilder.h"
+#include "llvm/Passes/PassPlugin.h"
 #include "llvm/Support/raw_ostream.h"
-#include "llvm/IR/LegacyPassManager.h"
-#include "llvm/Transforms/IPO/PassManagerBuilder.h"
+
 using namespace llvm;
 
 namespace {
-  struct SkeletonPass : public FunctionPass {
-    static char ID;
-    SkeletonPass() : FunctionPass(ID) {}
 
-    virtual bool runOnFunction(Function &F) {
-      errs() << "I saw a function called " << F.getName() << "!\n";
-      return false;
-    }
-  };
-}
+struct SkeletonPass : public PassInfoMixin<SkeletonPass> {
+    PreservedAnalyses run(Module &M, ModuleAnalysisManager &AM) {
+        for (auto &F : M.functions()) {
+            errs() << "I saw a function called " << F.getName() << "!\n";
+        }
+        return PreservedAnalyses::all();
+    };
+};
 
-char SkeletonPass::ID = 0;
+}
 
-// Automatically enable the pass.
-// http://adriansampson.net/blog/clangpass.html
-static void registerSkeletonPass(const PassManagerBuilder &,
-                         legacy::PassManagerBase &PM) {
-  PM.add(new SkeletonPass());
+extern "C" LLVM_ATTRIBUTE_WEAK ::llvm::PassPluginLibraryInfo
+llvmGetPassPluginInfo() {
+    return {
+        .APIVersion = LLVM_PLUGIN_API_VERSION,
+        .PluginName = "Skeleton pass",
+        .PluginVersion = "v0.1",
+        .RegisterPassBuilderCallbacks = [](PassBuilder &PB) {
+            PB.registerPipelineStartEPCallback(
+                [](ModulePassManager &MPM, OptimizationLevel Level) {
+                    MPM.addPass(SkeletonPass());
+                });
+        }
+    };
 }
-static RegisterStandardPasses
-  RegisterMyPass(PassManagerBuilder::EP_EarlyAsPossible,
-                 registerSkeletonPass);