[InstallAPI] Set InstallAPI as a standalone tool instead of CC1 action

Installapi has important distinctions when compared to the clang driver, so much that, it doesn't make much sense to try to integrate into it.
This patch partially reverts the CC1 action & driver support to replace with its own driver as a clang tool.
For distribution, we could use LLVM_TOOL_LLVM_DRIVER_BUILD mechanism for integrating the functionality into clang such that the toolchain size is less impacted.

Author: cyndyishida

clang/include/clang/InstallAPI/Context.h

@@ -0,0 +1,40 @@
+//===- InstallAPI/Context.h -------------------------------------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_INSTALLAPI_CONTEXT_H
+#define LLVM_CLANG_INSTALLAPI_CONTEXT_H
+
+#include "llvm/TextAPI/InterfaceFile.h"
+#include "llvm/TextAPI/RecordVisitor.h"
+#include "llvm/TextAPI/RecordsSlice.h"
+
+namespace clang {
+namespace installapi {
+
+/// Struct used for generating validating InstallAPI.
+/// The attributes captured represent all necessary information
+/// to generate TextAPI output.
+struct InstallAPIContext {
+
+  /// Library attributes that are typically passed as linker inputs.
+  llvm::MachO::RecordsSlice::BinaryAttrs BA;
+
+  /// Active target triple to parse.
+  llvm::Triple TargetTriple{};
+
+  /// File Path of output location.
+  StringRef OutputLoc{};
+
+  /// What encoding to write output as.
+  llvm::MachO::FileType FT = llvm::MachO::FileType::TBD_V5;
+};
+
+} // namespace installapi
+} // namespace clang
+
+#endif // LLVM_CLANG_INSTALLAPI_CONTEXT_H

clang/lib/CMakeLists.txt

@@ -23,6 +23,7 @@ add_subdirectory(Tooling)
 add_subdirectory(DirectoryWatcher)
 add_subdirectory(Index)
 add_subdirectory(IndexSerialization)
+add_subdirectory(InstallAPI)
 add_subdirectory(StaticAnalyzer)
 add_subdirectory(Format)
 if(CLANG_INCLUDE_TESTS)

clang/lib/InstallAPI/CMakeLists.txt

@@ -4,7 +4,6 @@ set(LLVM_LINK_COMPONENTS
   )
 
 add_clang_library(clangInstallAPI
-  Context.cpp
   FileList.cpp
   HeaderFile.cpp
 

clang/test/CMakeLists.txt

@@ -71,6 +71,7 @@ list(APPEND CLANG_TEST_DEPS
   clang-rename
   clang-refactor
   clang-diff
+  clang-installapi
   clang-scan-deps
   clang-linker-wrapper
   clang-offload-bundler

clang/test/InstallAPI/installapi-basic.test

@@ -0,0 +1,71 @@
+// RUN: rm -rf %t
+// RUN: split-file %s %t
+/// Check basic arguments are captured.
+// RUN: clang-installapi -x objective-c -target arm64-apple-ios13.0.0 \
+// RUN: -fapplication-extension -current_version 1 -install_name /usr/lib/basic.dylib \
+// RUN: %t/basic_inputs.json -o %t/basic.tbd 2>&1 | FileCheck %s --allow-empty
+// RUN: llvm-readtapi -compare %t/basic.tbd %t/expected.tbd 2>&1 | FileCheck %s --allow-empty
+
+/// Check multiple targets are captured.
+// RUN: clang-installapi -x objective-c -target arm64-apple-ios14.1 -target arm64e-apple-ios14.1 \
+// RUN: -fapplication-extension -install_name /usr/lib/basic.dylib \
+// RUN: %t/basic_inputs.json -o %t/multi-targets.tbd 2>&1 | FileCheck %s --allow-empty
+// RUN: llvm-readtapi -compare %t/multi-targets.tbd %t/expected-multi.tbd 2>&1 | FileCheck %s --allow-empty
+
+// CHECK-NOT: error:  
+// CHECK-NOT: warning:  
+
+//--- basic_inputs.json
+
+//--- expected.tbd
+{
+  "main_library": {
+    "compatibility_versions": [
+      {
+        "version": "0"
+      }
+    ],
+    "install_names": [
+      {
+        "name": "/usr/lib/basic.dylib"
+      }
+    ],
+    "target_info": [
+      {
+        "min_deployment": "13.0.0",
+        "target": "arm64-ios"
+      }
+    ]
+  },
+  "tapi_tbd_version": 5
+}
+
+//--- expected-multi.tbd
+{
+  "main_library": {
+    "compatibility_versions": [
+      {
+        "version": "0"
+      }],
+    "current_versions": [
+      {
+        "version": "0"
+      }],
+    "install_names": [
+      {
+        "name": "/usr/lib/basic.dylib"
+      }
+    ],
+    "target_info": [
+      {
+        "min_deployment": "14.1",
+        "target": "arm64-ios"
+      },
+      {
+        "min_deployment": "14.1",
+        "target": "arm64e-ios"
+      }
+    ]
+  },
+  "tapi_tbd_version": 5
+}

clang/test/InstallAPI/installapi-driver-invalid-options.test

@@ -0,0 +1,5 @@
+/// Check non-darwin triple is rejected.
+// RUN: not clang-installapi -target x86_64-unknown-unknown %s 2> %t 
+// RUN: FileCheck --check-prefix INVALID_INSTALLAPI -input-file %t %s
+// INVALID_INSTALLAPI: error: unsupported option 'installapi' for target 'x86_64-unknown-unknown'
+

clang/test/lit.cfg.py

@@ -90,13 +90,15 @@
     "clang-offload-packager",
     "clang-tblgen",
     "clang-scan-deps",
+    "clang-installapi",
     "opt",
     "llvm-ifs",
     "yaml2obj",
     "clang-linker-wrapper",
     "llvm-lto",
     "llvm-lto2",
     "llvm-profdata",
+    "llvm-readtapi",
     ToolSubst(
         "%clang_extdef_map",
         command=FindTool("clang-extdef-mapping"),

clang/tools/CMakeLists.txt

@@ -12,6 +12,7 @@ add_clang_subdirectory(clang-linker-wrapper)
 add_clang_subdirectory(clang-offload-packager)
 add_clang_subdirectory(clang-offload-bundler)
 add_clang_subdirectory(clang-scan-deps)
+add_clang_subdirectory(clang-installapi)
 if(HAVE_CLANG_REPL_SUPPORT)
   add_clang_subdirectory(clang-repl)
 endif()

clang/tools/clang-installapi/CMakeLists.txt

@@ -0,0 +1,20 @@
+set(LLVM_LINK_COMPONENTS
+  Support
+  TargetParser
+  TextAPI
+  )
+
+add_clang_tool(clang-installapi
+  ClangInstallAPI.cpp
+  Options.cpp
+
+  GENERATE_DRIVER
+  )
+
+clang_target_link_libraries(clang-installapi
+  PRIVATE
+  clangInstallAPI
+  clangDriver
+  clangFrontend
+  clangTooling
+  )

clang/tools/clang-installapi/ClangInstallAPI.cpp

@@ -0,0 +1,140 @@
+//===-- ClangInstallAPI.cpp ----------------------------------------------===//
+//
+// 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 the entry point to clang-installapi; it is a wrapper
+// for functionality in the InstallAPI clang library.
+//
+//===----------------------------------------------------------------------===//
+
+#include "Options.h"
+#include "clang/Basic/DiagnosticIDs.h"
+#include "clang/Driver/Driver.h"
+#include "clang/Driver/DriverDiagnostic.h"
+#include "clang/Frontend/CompilerInstance.h"
+#include "clang/Frontend/TextDiagnosticPrinter.h"
+#include "clang/InstallAPI/Context.h"
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/Option/Option.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/LLVMDriver.h"
+#include "llvm/Support/ManagedStatic.h"
+#include "llvm/Support/PrettyStackTrace.h"
+#include "llvm/Support/Process.h"
+#include "llvm/Support/Signals.h"
+#include "llvm/TargetParser/Host.h"
+#include "llvm/TextAPI/TextAPIWriter.h"
+
+using namespace clang;
+using namespace clang::installapi;
+using namespace clang::driver::options;
+using namespace llvm::opt;
+using namespace llvm::MachO;
+
+static InstallAPIContext createContextFromOptions(const Options &Opts) {
+  InstallAPIContext Ctx;
+  // InstallAPI requires two level namespacing.
+  Ctx.BA.TwoLevelNamespace = true;
+
+  Ctx.BA.InstallName = Opts.LinkerOpts.InstallName;
+  Ctx.BA.CurrentVersion = Opts.LinkerOpts.CurrentVersion;
+  Ctx.BA.AppExtensionSafe = Opts.LinkerOpts.AppExtensionSafe;
+  Ctx.FT = Opts.DriverOpts.OutFT;
+  Ctx.OutputLoc = Opts.DriverOpts.OutputPath;
+  return Ctx;
+}
+
+static bool run(ArrayRef<const char *> CommandArgs, const char *ProgName) {
+  // InstallAPI only needs to parse AST, so always force on certain options.
+  std::vector<const char *> Args;
+  Args.reserve(CommandArgs.size() + 1);
+  llvm::copy(CommandArgs, std::back_inserter(Args));
+  Args.push_back("-fsyntax-only");
+
+  // Setup Diagnostics engine.
+  IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts = new DiagnosticOptions();
+  const llvm::opt::OptTable &ClangOpts = clang::driver::getDriverOptTable();
+  unsigned MissingArgIndex, MissingArgCount;
+  llvm::opt::InputArgList ParsedArgs = ClangOpts.ParseArgs(
+      ArrayRef(Args).slice(1), MissingArgIndex, MissingArgCount);
+  ParseDiagnosticArgs(*DiagOpts, ParsedArgs);
+
+  IntrusiveRefCntPtr<DiagnosticsEngine> Diag = new clang::DiagnosticsEngine(
+      new clang::DiagnosticIDs(), DiagOpts.get(),
+      new clang::TextDiagnosticPrinter(llvm::errs(), DiagOpts.get()));
+
+  // Create file manager for all file operations.
+  IntrusiveRefCntPtr<clang::FileManager> FM(
+      new FileManager(clang::FileSystemOptions()));
+
+  // Set up driver to parse input arguments.
+  auto DriverArgs = llvm::ArrayRef(Args).slice(1);
+  clang::driver::Driver Driver(ProgName, llvm::sys::getDefaultTargetTriple(),
+                               *Diag, "clang installapi tool");
+  Driver.setInstalledDir(llvm::sys::path::parent_path(ProgName));
+  auto TargetAndMode =
+      clang::driver::ToolChain::getTargetAndModeFromProgramName(ProgName);
+  Driver.setTargetAndMode(TargetAndMode);
+  bool HasError = false;
+  llvm::opt::InputArgList ArgList =
+      Driver.ParseArgStrings(DriverArgs, /*UseDriverMode=*/true, HasError);
+  if (HasError)
+    return EXIT_FAILURE;
+  Driver.setCheckInputsExist(false);
+
+  // Capture InstallAPI specific options and diagnose any option errors.
+  Options Opts(*Diag, FM.get(), ArgList);
+  if (Diag->hasErrorOccurred())
+    return EXIT_FAILURE;
+  InstallAPIContext Ctx = createContextFromOptions(Opts);
+
+  // Set up compilation.
+  std::unique_ptr<CompilerInstance> CI(new CompilerInstance());
+  CI->setFileManager(FM.get());
+  CI->createDiagnostics();
+  if (!CI->hasDiagnostics())
+    return EXIT_FAILURE;
+
+  auto Out = CI->createOutputFile(Ctx.OutputLoc, /*Binary=*/false,
+                                  /*RemoveFileOnSignal=*/false,
+                                  /*UseTemporary=*/false,
+                                  /*CreateMissingDirectories=*/false);
+  if (!Out)
+    return EXIT_FAILURE;
+
+  // Assign attributes for serialization.
+  InterfaceFile IF;
+  for (const auto &TargetInfo : Opts.DriverOpts.Targets) {
+    IF.addTarget(TargetInfo.first);
+    IF.setFromBinaryAttrs(Ctx.BA, TargetInfo.first);
+  }
+
+  // Write output file and perform CI cleanup.
+  if (auto Err = TextAPIWriter::writeToStream(*Out, IF, Ctx.FT)) {
+    Diag->Report(diag::err_cannot_open_file) << Ctx.OutputLoc;
+    CI->clearOutputFiles(/*EraseFiles=*/true);
+    return EXIT_FAILURE;
+  }
+
+  CI->clearOutputFiles(/*EraseFiles=*/false);
+  return EXIT_SUCCESS;
+}
+
+int clang_installapi_main(int argc, char **argv,
+                          const llvm::ToolContext &ToolContext) {
+  // Standard set up, so program fails gracefully.
+  llvm::sys::PrintStackTraceOnErrorSignal(argv[0]);
+  llvm::PrettyStackTraceProgram StackPrinter(argc, argv);
+  llvm::llvm_shutdown_obj Shutdown;
+
+  if (llvm::sys::Process::FixupStandardFileDescriptors())
+    return EXIT_FAILURE;
+
+  const char *ProgName =
+      ToolContext.NeedsPrependArg ? ToolContext.PrependArg : ToolContext.Path;
+  return run(llvm::ArrayRef(argv, argc), ProgName);
+}