Feature/compiler extension

.github/workflows/llvm.yml

@@ -0,0 +1,34 @@
+name: CI
+
+on: [push]
+
+jobs:
+  build_llvm:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os:
+          - ubuntu-latest
+          - windows-latest
+          - macOS-latest
+        cmake_args:
+            - "-DLLVM_ENABLE_PROJECTS:STRING=clang;polly"
+    steps:
+    - name: Setup Windows
+      if: startsWith(matrix.os, 'windows')
+      uses: tstellar/actions/setup-windows@master
+      with:
+        arch: amd64
+    - uses: actions/checkout@v1
+      with:
+        fetch-depth: 1
+    - name: Install Ninja
+      uses: tstellar/actions/install-ninja@master
+      with:
+        os: ${{ runner.os }}
+    - name: Test LLVM
+      uses: tstellar/actions/build-test-llvm-project@master
+      with:
+        cmake_args: -G Ninja -DCMAKE_BUILD_TYPE=Release ${{ matrix.cmake_args }}
+        os: ${{ runner.os }}

clang/lib/CodeGen/BackendUtil.cpp

@@ -75,6 +75,10 @@
 using namespace clang;
 using namespace llvm;
 
+#define HANDLE_EXTENSION(Ext)                                                  \
+  llvm::PassPluginLibraryInfo get##Ext##PluginInfo();
+#include "llvm/Support/Extension.def"
+
 namespace {
 
 // Default filename used for profile generation.
@@ -1086,6 +1090,9 @@ void EmitAssemblyHelper::EmitAssemblyWithNewPassManager(
           << PluginFN << toString(PassPlugin.takeError());
     }
   }
+#define HANDLE_EXTENSION(Ext)                                                  \
+  get##Ext##PluginInfo().RegisterPassBuilderCallbacks(PB);
+#include "llvm/Support/Extension.def"
 
   LoopAnalysisManager LAM(CodeGenOpts.DebugPassManager);
   FunctionAnalysisManager FAM(CodeGenOpts.DebugPassManager);

clang/lib/CodeGen/CMakeLists.txt

@@ -95,6 +95,8 @@ add_clang_library(clangCodeGen
   TargetInfo.cpp
   VarBypassDetector.cpp
 
+  ENABLE_PLUGINS
+
   DEPENDS
   ${codegen_deps}
 

clang/tools/driver/CMakeLists.txt

@@ -122,7 +122,3 @@ if(CLANG_ORDER_FILE AND
     set_target_properties(clang PROPERTIES LINK_DEPENDS ${CLANG_ORDER_FILE})
   endif()
 endif()
-
-if(WITH_POLLY AND LINK_POLLY_INTO_TOOLS)
-  target_link_libraries(clang PRIVATE Polly)
-endif(WITH_POLLY AND LINK_POLLY_INTO_TOOLS)

clang/tools/driver/cc1_main.cpp

@@ -72,12 +72,6 @@ static void LLVMErrorHandler(void *UserData, const std::string &Message,
   exit(GenCrashDiag ? 70 : 1);
 }
 
-#ifdef LINK_POLLY_INTO_TOOLS
-namespace polly {
-void initializePollyPasses(llvm::PassRegistry &Registry);
-}
-#endif
-
 #ifdef CLANG_HAVE_RLIMITS
 #if defined(__linux__) && defined(__PIE__)
 static size_t getCurrentStackAllocation() {
@@ -203,11 +197,6 @@ int cc1_main(ArrayRef<const char *> Argv, const char *Argv0, void *MainAddr) {
   llvm::InitializeAllAsmPrinters();
   llvm::InitializeAllAsmParsers();
 
-#ifdef LINK_POLLY_INTO_TOOLS
-  llvm::PassRegistry &Registry = *llvm::PassRegistry::getPassRegistry();
-  polly::initializePollyPasses(Registry);
-#endif
-
   // Buffer diagnostics from argument parsing so that we can output them using a
   // well formed diagnostic object.
   IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts = new DiagnosticOptions();

llvm/CMakeLists.txt

@@ -465,29 +465,6 @@ set(LLVM_LIB_FUZZING_ENGINE "" CACHE PATH
 option(LLVM_USE_SPLIT_DWARF
   "Use -gsplit-dwarf when compiling llvm." OFF)
 
-option(LLVM_POLLY_LINK_INTO_TOOLS "Statically link Polly into tools (if available)" ON)
-option(LLVM_POLLY_BUILD "Build LLVM with Polly" ON)
-
-if (EXISTS ${LLVM_MAIN_SRC_DIR}/tools/polly/CMakeLists.txt)
-  set(POLLY_IN_TREE TRUE)
-elseif(LLVM_EXTERNAL_POLLY_SOURCE_DIR)
-  set(POLLY_IN_TREE TRUE)
-else()
-  set(POLLY_IN_TREE FALSE)
-endif()
-
-if (LLVM_POLLY_BUILD AND POLLY_IN_TREE)
-  set(WITH_POLLY ON)
-else()
-  set(WITH_POLLY OFF)
-endif()
-
-if (LLVM_POLLY_LINK_INTO_TOOLS AND WITH_POLLY)
-  set(LINK_POLLY_INTO_TOOLS ON)
-else()
-  set(LINK_POLLY_INTO_TOOLS OFF)
-endif()
-
 # Define an option controlling whether we should build for 32-bit on 64-bit
 # platforms, where supported.
 if( CMAKE_SIZEOF_VOID_P EQUAL 8 AND NOT WIN32 )
@@ -1109,3 +1086,5 @@ endif()
 if (LLVM_INCLUDE_UTILS AND LLVM_INCLUDE_TOOLS)
   add_subdirectory(utils/llvm-locstats)
 endif()
+
+process_llvm_pass_plugins()

llvm/cmake/modules/AddLLVM.cmake

@@ -400,7 +400,7 @@ endfunction(set_windows_version_resource_properties)
 #   )
 function(llvm_add_library name)
   cmake_parse_arguments(ARG
-    "MODULE;SHARED;STATIC;OBJECT;DISABLE_LLVM_LINK_LLVM_DYLIB;SONAME;NO_INSTALL_RPATH"
+    "MODULE;SHARED;STATIC;OBJECT;DISABLE_LLVM_LINK_LLVM_DYLIB;SONAME;NO_INSTALL_RPATH;ENABLE_PLUGINS"
     "OUTPUT_NAME;PLUGIN_TOOL;ENTITLEMENTS;BUNDLE_PATH"
     "ADDITIONAL_HEADERS;DEPENDS;LINK_COMPONENTS;LINK_LIBS;OBJLIBS"
     ${ARGN})
@@ -414,6 +414,9 @@ function(llvm_add_library name)
   else()
     llvm_process_sources(ALL_FILES ${ARG_UNPARSED_ARGUMENTS} ${ARG_ADDITIONAL_HEADERS})
   endif()
+  if(ARG_ENABLE_PLUGINS)
+    set_property(GLOBAL APPEND PROPERTY LLVM_PLUGIN_TARGETS ${name})
+  endif()
 
   if(ARG_MODULE)
     if(ARG_SHARED OR ARG_STATIC)
@@ -732,7 +735,7 @@ endmacro(add_llvm_library name)
 
 macro(add_llvm_executable name)
   cmake_parse_arguments(ARG
-    "DISABLE_LLVM_LINK_LLVM_DYLIB;IGNORE_EXTERNALIZE_DEBUGINFO;NO_INSTALL_RPATH;SUPPORT_PLUGINS"
+    "DISABLE_LLVM_LINK_LLVM_DYLIB;IGNORE_EXTERNALIZE_DEBUGINFO;NO_INSTALL_RPATH;SUPPORT_PLUGINS;ENABLE_PLUGINS"
     "ENTITLEMENTS;BUNDLE_PATH"
     "DEPENDS"
     ${ARGN})
@@ -819,10 +822,78 @@ macro(add_llvm_executable name)
     # API for all shared libaries loaded by this executable.
     target_link_libraries(${name} PRIVATE ${LLVM_PTHREAD_LIB})
   endif()
+  if(ARG_ENABLE_PLUGINS)
+    set_property(GLOBAL APPEND PROPERTY LLVM_PLUGIN_TARGETS ${name})
+  endif()
 
   llvm_codesign(${name} ENTITLEMENTS ${ARG_ENTITLEMENTS} BUNDLE_PATH ${ARG_BUNDLE_PATH})
 endmacro(add_llvm_executable name)
 
+# add_llvm_pass_plugin(name)
+#   Add ${name} as an llvm plugin.
+#   If option LLVM_${name_upper}_LINK_INTO_TOOLS is set to ON, the plugin is registered statically.
+#   Otherwise a pluggable shared library is registered.
+function(add_llvm_pass_plugin name)
+
+  string(TOUPPER ${name} name_upper)
+
+  option(LLVM_${name_upper}_LINK_INTO_TOOLS "Statically link ${name} into tools (if available)" OFF)
+
+  # process_llvm_pass_plugins takes care of the actual linking, just create an
+  # object library as of now
+  add_llvm_library(${name} OBJECT ${ARGN})
+
+  if(LLVM_${name_upper}_LINK_INTO_TOOLS)
+      target_compile_definitions(${name} PRIVATE LLVM_${name_upper}_LINK_INTO_TOOLS)
+      set_property(TARGET ${name} APPEND PROPERTY COMPILE_DEFINITIONS LLVM_LINK_INTO_TOOLS)
+      if (TARGET intrinsics_gen)
+        add_dependencies(obj.${name} intrinsics_gen)
+      endif()
+  endif()
+
+  message(STATUS "Registering ${name} as a pass plugin (static build: ${LLVM_${name_upper}_LINK_INTO_TOOLS})")
+  if(LLVM_${name_upper}_LINK_INTO_TOOLS)
+    set_property(GLOBAL APPEND PROPERTY LLVM_COMPILE_EXTENSIONS ${name})
+  endif()
+endfunction(add_llvm_pass_plugin)
+
+# Generate X Macro file for extension handling. It provides a
+# HANDLE_EXTENSION(extension_namespace, ExtensionProject) call for each extension
+# allowing client code to define HANDLE_EXTENSION to have a specific code be run for
+# each extension.
+#
+# Also correctly set lib dependencies between plugins and tools.
+function(process_llvm_pass_plugins)
+  get_property(LLVM_EXTENSIONS GLOBAL PROPERTY LLVM_COMPILE_EXTENSIONS)
+  file(WRITE "${CMAKE_BINARY_DIR}/include/llvm/Support/Extension.def.tmp" "//extension handlers\n")
+  foreach(llvm_extension ${LLVM_EXTENSIONS})
+    string(TOLOWER ${llvm_extension} llvm_extension_lower)
+
+    string(TOUPPER ${llvm_extension} llvm_extension_upper)
+    string(SUBSTRING ${llvm_extension_upper} 0 1 llvm_extension_upper_first)
+    string(SUBSTRING ${llvm_extension_lower} 1 -1 llvm_extension_lower_tail)
+    string(CONCAT llvm_extension_project ${llvm_extension_upper_first} ${llvm_extension_lower_tail})
+
+    if(LLVM_${llvm_extension_upper}_LINK_INTO_TOOLS)
+        file(APPEND "${CMAKE_BINARY_DIR}/include/llvm/Support/Extension.def.tmp" "HANDLE_EXTENSION(${llvm_extension_project})\n")
+
+        get_property(llvm_plugin_targets GLOBAL PROPERTY LLVM_PLUGIN_TARGETS)
+        foreach(llvm_plugin_target ${llvm_plugin_targets})
+          set_property(TARGET ${llvm_plugin_target} APPEND PROPERTY LINK_LIBRARIES ${llvm_extension})
+          set_property(TARGET ${llvm_plugin_target} APPEND PROPERTY INTERFACE_LINK_LIBRARIES ${llvm_extension})
+        endforeach()
+    else()
+      add_llvm_library(${llvm_extension_lower} MODULE obj.${llvm_extension_lower})
+    endif()
+
+  endforeach()
+  file(APPEND "${CMAKE_BINARY_DIR}/include/llvm/Support/Extension.def.tmp" "#undef HANDLE_EXTENSION\n")
+
+  # only replace if there's an actual change
+  execute_process(COMMAND ${CMAKE_COMMAND} -E copy_if_different "${CMAKE_BINARY_DIR}/include/llvm/Support/Extension.def.tmp" "${CMAKE_BINARY_DIR}/include/llvm/Support/Extension.def")
+  file(REMOVE "${CMAKE_BINARY_DIR}/include/llvm/Support/Extension.def.tmp")
+endfunction()
+
 function(export_executable_symbols target)
   if (LLVM_EXPORTED_SYMBOL_FILE)
     # The symbol file should contain the symbols we want the executable to

llvm/docs/WritingAnLLVMPass.rst

@@ -1175,6 +1175,32 @@ implement ``releaseMemory`` to, well, release the memory allocated to maintain
 this internal state.  This method is called after the ``run*`` method for the
 class, before the next call of ``run*`` in your pass.
 
+Building pass plugins
+=====================
+
+As an alternative to using ``PLUGIN_TOOL``, LLVM provides a mechanism to
+automatically register pass plugins within ``clang``, ``opt`` and ``bugpoint``.
+One first needs to create an independent project and add it to either ``tools/``
+or, using the MonoRepo layout, at the root of the repo alongside other projects.
+This project must contain the following minimal ``CMakeLists.txt``:
+
+.. code-block:: cmake
+
+    add_llvm_pass_plugin(Name source0.cpp)
+
+The pass must provide two entry points for the new pass manager, one for static
+registration and one for dynamically loaded plugins:
+
+- ``llvm::PassPluginLibraryInfo get##Name##PluginInfo();``
+- ``extern "C" ::llvm::PassPluginLibraryInfo llvmGetPassPluginInfo() LLVM_ATTRIBUTE_WEAK;``
+
+Pass plugins are compiled and link dynamically by default, but it's
+possible to set the following variables to change this behavior:
+
+- ``LLVM_${NAME}_LINK_INTO_TOOLS``, when sets to ``ON``, turns the project into
+  a statically linked extension
+
+
 Registering dynamically loaded passes
 =====================================
 

llvm/examples/Bye/Bye.cpp

@@ -0,0 +1,69 @@
+#include "llvm/IR/Function.h"
+#include "llvm/IR/LegacyPassManager.h"
+#include "llvm/Pass.h"
+#include "llvm/Passes/PassBuilder.h"
+#include "llvm/Passes/PassPlugin.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Transforms/IPO/PassManagerBuilder.h"
+
+using namespace llvm;
+
+static cl::opt<bool> Wave("wave-goodbye", cl::init(false),
+                          cl::desc("wave good bye"));
+
+namespace {
+
+bool runBye(Function &F) {
+  if (Wave) {
+    errs() << "Bye: ";
+    errs().write_escaped(F.getName()) << '\n';
+  }
+  return false;
+}
+
+struct LegacyBye : public FunctionPass {
+  static char ID;
+  LegacyBye() : FunctionPass(ID) {}
+  bool runOnFunction(Function &F) override { return runBye(F); }
+};
+
+struct Bye : PassInfoMixin<Bye> {
+  PreservedAnalyses run(Function &F, FunctionAnalysisManager &) {
+    if (!runBye(F))
+      return PreservedAnalyses::all();
+    return PreservedAnalyses::none();
+  }
+};
+
+} // namespace
+
+char LegacyBye::ID = 0;
+
+static RegisterPass<LegacyBye> X("goodbye", "Good Bye World Pass",
+                                 false /* Only looks at CFG */,
+                                 false /* Analysis Pass */);
+
+/* Legacy PM Registration */
+static llvm::RegisterStandardPasses RegisterBye(
+    llvm::PassManagerBuilder::EP_EarlyAsPossible,
+    [](const llvm::PassManagerBuilder &Builder,
+       llvm::legacy::PassManagerBase &PM) { PM.add(new LegacyBye()); });
+
+/* New PM Registration */
+llvm::PassPluginLibraryInfo getByePluginInfo() {
+  return {LLVM_PLUGIN_API_VERSION, "Bye", LLVM_VERSION_STRING,
+          [](PassBuilder &PB) {
+            PB.registerVectorizerStartEPCallback(
+                [](llvm::FunctionPassManager &PM,
+                   llvm::PassBuilder::OptimizationLevel Level) {
+                  PM.addPass(Bye());
+                });
+          }};
+}
+
+#ifndef LLVM_BYE_LINK_INTO_TOOLS
+extern "C" LLVM_ATTRIBUTE_WEAK ::llvm::PassPluginLibraryInfo
+llvmGetPassPluginInfo() {
+  return getByePluginInfo();
+}
+#endif

llvm/examples/Bye/CMakeLists.txt

@@ -0,0 +1,13 @@
+add_llvm_pass_plugin(Bye Bye.cpp)
+if (LLVM_LINK_LLVM_DYLIB)
+  target_link_libraries(Bye PUBLIC LLVM)
+else()
+  target_link_libraries(Bye
+    PUBLIC
+    LLVMSupport
+    LLVMCore
+    LLVMipo
+    LLVMPasses
+    )
+endif()
+

llvm/examples/CMakeLists.txt

@@ -7,6 +7,7 @@ add_subdirectory(LLJITExamples)
 add_subdirectory(Kaleidoscope)
 add_subdirectory(ModuleMaker)
 add_subdirectory(SpeculativeJIT)
+add_subdirectory(Bye)
 
 if(LLVM_ENABLE_EH AND (NOT WIN32) AND (NOT "${LLVM_NATIVE_ARCH}" STREQUAL "ARM"))
     add_subdirectory(ExceptionDemo)

llvm/include/llvm/Config/llvm-config.h.cmake

@@ -17,9 +17,6 @@
 /* Define if LLVM_ENABLE_DUMP is enabled */
 #cmakedefine LLVM_ENABLE_DUMP
 
-/* Define if we link Polly to the tools */
-#cmakedefine LINK_POLLY_INTO_TOOLS
-
 /* Target triple LLVM will generate code for by default */
 #cmakedefine LLVM_DEFAULT_TARGET_TRIPLE "${LLVM_DEFAULT_TARGET_TRIPLE}"
 

llvm/test/Feature/load_extension.ll

@@ -0,0 +1,11 @@
+; RUN: opt %s -load=%llvmshlibdir/libBye%shlibext -goodbye -wave-goodbye \
+; RUN:   -disable-output 2>&1 | FileCheck %s
+; REQUIRES: plugins
+; CHECK: Bye
+
+@junk = global i32 0
+
+define i32* @somefunk() {
+  ret i32* @junk
+}
+