generate the list of compatibility macros in a host tool

Author: QuietMisdreavus

lib/PrintAsClang/ClangMacros.def renamed to include/swift/PrintAsClang/ClangMacros.def

@@ -14,19 +14,3 @@ target_link_libraries(swiftPrintAsClang PRIVATE
   swiftIDE)
 
 set_swift_llvm_is_available(swiftPrintAsClang)
-
-# Add target to install the list of symbols added to compatibility headers
-set(symbols_file "${CMAKE_CURRENT_SOURCE_DIR}/compatibility_symbols")
-
-add_custom_target(swift-compatibility-symbols DEPENDS ${symbols_file})
-
-add_dependencies(swiftPrintAsClang swift-compatibility-symbols)
-
-swift_install_in_component(
-  FILES
-    ${symbols_file}
-  DESTINATION
-    "share/swift"
-  COMPONENT
-    compiler
-)

lib/PrintAsClang/CMakeLists.txt

@@ -53,8 +53,6 @@ static void emitObjCConditional(raw_ostream &out,
 static void writePrologue(raw_ostream &out, ASTContext &ctx,
                           StringRef macroGuard) {
 
-  // NOTE: If you add macros to this prologue, also add them to the `compatibility_symbols` file!
-
   out << "// Generated by "
       << version::getSwiftFullVersion(ctx.LangOpts.EffectiveLanguageVersion)
       << "\n"
@@ -148,7 +146,7 @@ static void writePrologue(raw_ostream &out, ASTContext &ctx,
          BODY "\n" \
          "#endif\n";
 
-#include "ClangMacros.def"
+#include "swift/PrintAsClang/ClangMacros.def"
 
   static_assert(SWIFT_MAX_IMPORTED_SIMD_ELEMENTS == 4,
               "need to add SIMD typedefs here if max elements is increased");

lib/PrintAsClang/PrintAsClang.cpp

@@ -19,6 +19,7 @@ endif()
 
 add_swift_tool_subdirectory(driver)
 add_swift_tool_subdirectory(sil-opt)
+add_swift_tool_subdirectory(swift-compatibility-symbols)
 add_swift_tool_subdirectory(swift-dependency-tool)
 add_swift_tool_subdirectory(swift-demangle)
 add_swift_tool_subdirectory(swift-demangle-yamldump)

lib/PrintAsClang/compatibility_symbols

@@ -0,0 +1,28 @@
+add_swift_host_tool(swift-compatibility-symbols
+  swift-compatibility-symbols.cpp
+  LLVM_LINK_COMPONENTS support
+  SWIFT_COMPONENT tools
+)
+
+set(syms_file "${CMAKE_BINARY_DIR}/share/swift/compatibility-symbols")
+
+add_custom_command_target(copy_compat_target
+  OUTPUT
+    ${syms_file}
+  COMMAND
+    "${SWIFT_NATIVE_SWIFT_TOOLS_PATH}/swift-compatibility-symbols"
+      --output-filename ${syms_file}
+  DEPENDS
+    swift-compatibility-symbols
+)
+
+add_dependencies(swift-frontend "${copy_compat_target}")
+
+swift_install_in_component(
+  FILES
+    ${syms_file}
+  DESTINATION
+    "share/swift"
+  COMPONENT
+    compiler
+)

tools/CMakeLists.txt

@@ -0,0 +1,89 @@
+//===--- swift-compatibility-symbols.cpp - Emit Clang symbol list ---------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2022 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+//
+// A simple program to dynamically generate the list of macros added to
+// compatibility headers.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/raw_ostream.h"
+
+#include <algorithm>
+#include <cstdlib>
+#include <iostream>
+#include <system_error>
+
+namespace options {
+
+static llvm::cl::OptionCategory Category("swift-compatibility-symbols Options");
+
+static llvm::cl::opt<std::string>
+  OutputFilename("output-filename",
+                 llvm::cl::desc("Filename for the output file"),
+                 llvm::cl::init("-"),
+                 llvm::cl::cat(Category));
+
+}
+
+int main(int argc, char *argv[]) {
+  llvm::cl::HideUnrelatedOptions(options::Category);
+  llvm::cl::ParseCommandLineOptions(argc, argv,
+                                    "Swift Compatibility Symbols listing\n");
+
+  std::error_code error;
+  llvm::raw_fd_ostream OS(options::OutputFilename, error, llvm::sys::fs::CD_CreateAlways);
+  if (OS.has_error() || error) {
+    llvm::errs() << "Error when trying to write to output file; error code "
+                 << error.message() << "\n";
+    return EXIT_FAILURE;
+  }
+
+  llvm::SmallVector<llvm::StringRef, 40> symbols;
+#define CLANG_MACRO_DEFINED(NAME) \
+  symbols.push_back(#NAME);
+
+#define CLANG_MACRO(NAME, ARGS, VALUE) \
+  CLANG_MACRO_DEFINED(NAME)
+
+#define CLANG_MACRO_BODY(NAME, BODY) \
+  CLANG_MACRO_DEFINED(NAME)
+
+#define CLANG_MACRO_ALTERNATIVE(NAME, ARGS, CONDITION, VALUE, ALTERNATIVE) \
+  CLANG_MACRO_DEFINED(NAME)
+
+#define CLANG_MACRO_CONDITIONAL(NAME, ARGS, CONDITION, VALUE) \
+  CLANG_MACRO_DEFINED(NAME)
+
+#define CLANG_MACRO_OBJC(NAME, ARGS, VALUE) \
+  CLANG_MACRO_DEFINED(NAME)
+
+#define CLANG_MACRO_CXX(NAME, ARGS, VALUE, ALTERNATIVE) \
+  CLANG_MACRO_DEFINED(NAME)
+
+#define CLANG_MACRO_CXX_BODY(NAME, BODY) \
+  CLANG_MACRO_DEFINED(NAME)
+
+#include "swift/PrintAsClang/ClangMacros.def"
+
+  std::sort(symbols.begin(), symbols.end());
+
+  for (const llvm::StringRef sym : symbols) {
+    OS << sym << "\n";
+  }
+
+  return EXIT_SUCCESS;
+}
+