[FileCheck] Move FileCheck implementation out of LLVMSupport into its own library

[teemperor]

Summary

The actual FileCheck logic seems to be implemented in LLVMSupport. I don't see a good
reason for having FileCheck implemented there as it has a very specific use while LLVMSupport
is a dependency of pretty much every LLVM tool there is. In fact, the only use of FileCheck I
could find (outside the FileCheck tool and the FileCheck unit test) is a single call in GISelMITest.h.

This moves the FileCheck logic to its own LLVMFileCheck library. This way only FileCheck and
the GlobalISelTests now have a dependency on this code.

[thopre]

A big thank you, it'll speed up incremental debug build considerably. LGTM but I'm not too well versed in the CMake aspects of making a LLVM libraries so I'll let someone else approve this change.

[jhenderson]

All looks good to me, with the exception of a couple of inline nits, and the fact that I know nothing about the modulemap stuff (but the latter looks right, based on what is done elsewhere within it).

llvm/include/llvm/FileCheck/FileCheck.h

12–14

Include guards need updating.

llvm/lib/FileCheck/FileCheckImpl.h

14–16

Ditto.

[teemperor]

• Fix header guards (thanks @jhenderson!)
• Adapt GN build files too.

[teemperor]

Thanks for the quick review!

[thakis]

Thanks for updating the GN files! I just wanted to point out that updating them is completely optional.

[chandlerc]

Somewhat minor post-commit thought, but we now have both a library FileCheck and an executable binary FileCheck (not to mention the existing confusion of having two FileCheck.cpp files).

Might be nice to think about a naming scheme that would reduce these collisions?

[teemperor]

In D86344#2260056, @chandlerc wrote:

Somewhat minor post-commit thought, but we now have both a library FileCheck and an executable binary FileCheck (not to mention the existing confusion of having two FileCheck.cpp files).

Might be nice to think about a naming scheme that would reduce these collisions?

It's kinda similar for tablegen, but there we don't have the problem of the executable having a upper camel case name (LLVMTableGen and llvm-tblgen). Here it's LLVMFileCheck and FileCheck. Renaming the library would be inconsistent with the other LLVM library names (which have an LLVM prefix) and I renaming FileCheck seems like a humongous task. We could rename the library to something else though...

For the file name, maybe FileCheckFrontend.cpp for the FileCheck executable source?

llvm/include/llvm/FileCheck/FileCheck.h

-//==-- llvm/Support/FileCheck.h ---------------------------*- C++ -*-==//
+//==-- llvm/FileCheck/FileCheck.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
 //
 //===----------------------------------------------------------------------===//
 //
 /// \file This file has some utilities to use FileCheck as an API
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_SUPPORT_FILECHECK_H
-#define LLVM_SUPPORT_FILECHECK_H
+#ifndef LLVM_FILECHECK_FILECHECK_H
+#define LLVM_FILECHECK_FILECHECK_H
 
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/Regex.h"
 #include "llvm/Support/SourceMgr.h"
 #include <string>
 #include <vector>
 

llvm/include/llvm/module.modulemap

module LLVM_ExecutionEngine {
   // Exclude headers from LLVM_OrcSupport.
   exclude header "ExecutionEngine/Orc/OrcError.h"
   exclude header "ExecutionEngine/Orc/RPC/RPCUtils.h"
   exclude header "ExecutionEngine/Orc/RPC/RPCSerialization.h"
   exclude header "ExecutionEngine/Orc/RPC/RawByteChannel.h"
 
 }
 
+module LLVM_FileCheck {
+  requires cplusplus
+
+  umbrella "FileCheck"
+  module * { export * }
+}
+
 // Orc utilities that don't depend only on Support (not ExecutionEngine or
 // IR). This is a workaround for ExecutionEngine's broken layering, and will
 // be removed in the future.
 module LLVM_OrcSupport {
   requires cplusplus
 
   header "ExecutionEngine/Orc/OrcError.h"
   header "ExecutionEngine/Orc/RPC/RPCUtils.h"

llvm/lib/CMakeLists.txt

 # `Demangle', `Support' and `TableGen' libraries are added on the top-level
 # CMakeLists.txt
 
 add_subdirectory(IR)
 add_subdirectory(FuzzMutate)
+add_subdirectory(FileCheck)
 add_subdirectory(InterfaceStub)
 add_subdirectory(IRReader)
 add_subdirectory(CodeGen)
 add_subdirectory(BinaryFormat)
 add_subdirectory(Bitcode)
 add_subdirectory(Bitstream)
 add_subdirectory(DWARFLinker)
 add_subdirectory(Extensions)

llvm/lib/FileCheck/CMakeLists.txt

+add_llvm_component_library(LLVMFileCheck
+  FileCheck.cpp
+
+  ADDITIONAL_HEADER_DIRS
+  "${LLVM_MAIN_INCLUDE_DIR}/llvm/FileCheck"
+)

llvm/lib/FileCheck/FileCheck.cpp

 //===- FileCheck.cpp - Check that File's Contents match what is expected --===//
 //
 // 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
 //
 //===----------------------------------------------------------------------===//
 //
 // FileCheck does a line-by line check of a file that validates whether it
 // contains the expected content.  This is useful for regression tests etc.
 //
 // This file implements most of the API that will be used by the FileCheck utility
 // as well as various unittests.
 //===----------------------------------------------------------------------===//
 
-#include "llvm/Support/FileCheck.h"
+#include "llvm/FileCheck/FileCheck.h"
 #include "FileCheckImpl.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/StringSet.h"
 #include "llvm/ADT/Twine.h"
 #include "llvm/Support/CheckedArithmetic.h"
 #include "llvm/Support/FormatVariadic.h"
 #include <cstdint>
 #include <list>

llvm/lib/FileCheck/FileCheckImpl.h

 //===-- FileCheckImpl.h - Private FileCheck Interface ------------*- 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
 //
 //===----------------------------------------------------------------------===//
 //
 // This file defines the private interfaces of FileCheck. Its purpose is to
 // allow unit testing of FileCheck and to separate the interface from the
 // implementation. It is only meant to be used by FileCheck.
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_LIB_SUPPORT_FILECHECKIMPL_H
-#define LLVM_LIB_SUPPORT_FILECHECKIMPL_H
+#ifndef LLVM_LIB_FILECHECK_FILECHECKIMPL_H
+#define LLVM_LIB_FILECHECK_FILECHECKIMPL_H
 
-#include "llvm/Support/FileCheck.h"
 #include "llvm/ADT/Optional.h"
 #include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/StringRef.h"
+#include "llvm/FileCheck/FileCheck.h"
 #include "llvm/Support/Error.h"
 #include "llvm/Support/SourceMgr.h"
 #include <map>
 #include <string>
 #include <vector>
 
 namespace llvm {
 

llvm/lib/Support/CMakeLists.txt

add_llvm_component_library(LLVMSupport
   DeltaAlgorithm.cpp
   DAGDeltaAlgorithm.cpp
   DJB.cpp
   ELFAttributeParser.cpp
   ELFAttributes.cpp
   Error.cpp
   ErrorHandling.cpp
   ExtensibleRTTI.cpp
-  FileCheck.cpp
   FileCollector.cpp
   FileUtilities.cpp
   FileOutputBuffer.cpp
   FoldingSet.cpp
   FormattedStream.cpp
   FormatVariadic.cpp
   GlobPattern.cpp
   GraphWriter.cpp

llvm/unittests/CMakeLists.txt

 add_subdirectory(AsmParser)
 add_subdirectory(BinaryFormat)
 add_subdirectory(Bitcode)
 add_subdirectory(Bitstream)
 add_subdirectory(CodeGen)
 add_subdirectory(DebugInfo)
 add_subdirectory(Demangle)
 add_subdirectory(ExecutionEngine)
+add_subdirectory(FileCheck)
 add_subdirectory(Frontend)
 add_subdirectory(FuzzMutate)
 add_subdirectory(InterfaceStub)
 add_subdirectory(IR)
 add_subdirectory(LineEditor)
 add_subdirectory(Linker)
 add_subdirectory(MC)
 add_subdirectory(MI)

llvm/unittests/CodeGen/GlobalISel/CMakeLists.txt

 set(LLVM_LINK_COMPONENTS
   ${LLVM_TARGETS_TO_BUILD}
   CodeGen
   Core
+  FileCheck
   GlobalISel
   MC
   MIRParser
   Support
   Target
   )
 
 add_llvm_unittest(GlobalISelTests

llvm/unittests/CodeGen/GlobalISel/GISelMITest.h

 #include "llvm/CodeGen/GlobalISel/Utils.h"
 #include "llvm/CodeGen/MIRParser/MIRParser.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/CodeGen/MachineModuleInfo.h"
 #include "llvm/CodeGen/TargetFrameLowering.h"
 #include "llvm/CodeGen/TargetInstrInfo.h"
 #include "llvm/CodeGen/TargetLowering.h"
 #include "llvm/CodeGen/TargetSubtargetInfo.h"
+#include "llvm/FileCheck/FileCheck.h"
 #include "llvm/InitializePasses.h"
-#include "llvm/Support/FileCheck.h"
 #include "llvm/Support/SourceMgr.h"
 #include "llvm/Support/TargetRegistry.h"
 #include "llvm/Support/TargetSelect.h"
 #include "llvm/Target/TargetMachine.h"
 #include "llvm/Target/TargetOptions.h"
 #include "gtest/gtest.h"
 
 using namespace llvm;

llvm/unittests/FileCheck/CMakeLists.txt

+set(LLVM_LINK_COMPONENTS
+  FileCheck
+  Support
+)
+
+add_llvm_unittest(FileCheckTests
+  FileCheckTest.cpp
+)
+
+target_link_libraries(FileCheckTests PRIVATE LLVMTestingSupport)

llvm/unittests/FileCheck/FileCheckTest.cpp

-//===- llvm/unittest/Support/FileCheckTest.cpp - FileCheck tests --===//
+//===- llvm/unittest/FileCheck/FileCheckTest.cpp - FileCheck tests --------===//
 //
 // 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
 //
 //===----------------------------------------------------------------------===//
 
-#include "llvm/Support/FileCheck.h"
-#include "../lib/Support/FileCheckImpl.h"
+#include "llvm/FileCheck/FileCheck.h"
+#include "../lib/FileCheck/FileCheckImpl.h"
 #include "llvm/Support/Regex.h"
 #include "llvm/Testing/Support/Error.h"
 #include "gtest/gtest.h"
 #include <tuple>
 #include <unordered_set>
 
 using namespace llvm;
 

llvm/unittests/Support/CMakeLists.txt

add_llvm_unittest(SupportTests
   DJBTest.cpp
   EndianStreamTest.cpp
   EndianTest.cpp
   ELFAttributeParserTest.cpp
   ErrnoTest.cpp
   ErrorOrTest.cpp
   ErrorTest.cpp
   ExtensibleRTTITest.cpp
-  FileCheckTest.cpp
   FileCollectorTest.cpp
   FileOutputBufferTest.cpp
   FileUtilitiesTest.cpp
   FormatVariadicTest.cpp
   GlobPatternTest.cpp
   Host.cpp
   IndexedAccessorTest.cpp
   ItaniumManglingCanonicalizerTest.cpp

llvm/utils/FileCheck/CMakeLists.txt

 add_llvm_utility(FileCheck
   FileCheck.cpp
   )
 
-target_link_libraries(FileCheck PRIVATE LLVMSupport)
+target_link_libraries(FileCheck PRIVATE LLVMFileCheck LLVMSupport)

llvm/utils/FileCheck/FileCheck.cpp

 // contains the expected content.  This is useful for regression tests etc.
 //
 // This program exits with an exit status of 2 on error, exit status of 0 if
 // the file matched the expected contents, and exit status of 1 if it did not
 // contain the expected contents.
 //
 //===----------------------------------------------------------------------===//
 
+#include "llvm/FileCheck/FileCheck.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/InitLLVM.h"
 #include "llvm/Support/Process.h"
 #include "llvm/Support/WithColor.h"
 #include "llvm/Support/raw_ostream.h"
-#include "llvm/Support/FileCheck.h"
 #include <cmath>
 using namespace llvm;
 
 static cl::extrahelp FileCheckOptsEnv(
     "\nOptions are parsed from the environment variable FILECHECK_OPTS and\n"
     "from the command line.\n");
 
 static cl::opt<std::string>

llvm/utils/gn/secondary/llvm/lib/FileCheck/BUILD.gn

+static_library("FileCheck") {
+  output_name = "LLVMFileCheck"
+  deps = [ "//llvm/lib/Support" ]
+  sources = [
+    "FileCheck.cpp",
+  ]
+}

llvm/utils/gn/secondary/llvm/lib/Support/BUILD.gn

sources = [
     "Debug.cpp",
     "DebugCounter.cpp",
     "DeltaAlgorithm.cpp",
     "ELFAttributeParser.cpp",
     "ELFAttributes.cpp",
     "Error.cpp",
     "ErrorHandling.cpp",
     "ExtensibleRTTI.cpp",
-    "FileCheck.cpp",
     "FileCollector.cpp",
     "FileOutputBuffer.cpp",
     "FileUtilities.cpp",
     "FoldingSet.cpp",
     "FormatVariadic.cpp",
     "FormattedStream.cpp",
     "GlobPattern.cpp",
     "GraphWriter.cpp",

llvm/utils/gn/secondary/llvm/unittests/BUILD.gn

deps = [
     "DebugInfo/GSYM:DebugInfoGSYMTests",
     "DebugInfo/MSF:DebugInfoMSFTests",
     "DebugInfo/PDB:DebugInfoPDBTests",
     "Demangle:DemangleTests",
     "ExecutionEngine:ExecutionEngineTests",
     "ExecutionEngine/JITLink:JITLinkTests",
     "ExecutionEngine/MCJIT:MCJITTests",
     "ExecutionEngine/Orc:OrcJITTests",
+    "FileCheck:FileCheckTests",
     "Frontend:LLVMFrontendTests",
     "FuzzMutate:FuzzMutateTests",
     "IR:IRTests",
     "InterfaceStub:InterfaceStubTests",
     "LineEditor:LineEditorTests",
     "Linker:LinkerTests",
     "MC:MCTests",
     "MI:MITests",

llvm/utils/gn/secondary/llvm/unittests/CodeGen/GlobalISel/BUILD.gn

 import("//llvm/utils/unittest/unittest.gni")
 
 unittest("GlobalISelTests") {
   deps = [
     "//llvm/lib/CodeGen",
     "//llvm/lib/CodeGen/GlobalISel",
     "//llvm/lib/CodeGen/MIRParser",
+    "//llvm/lib/FileCheck",
     "//llvm/lib/IR",
     "//llvm/lib/MC",
     "//llvm/lib/Support",
     "//llvm/lib/Target",
     "//llvm/lib/Target:TargetsToBuild",
   ]
   sources = [
     "CSETest.cpp",

llvm/utils/gn/secondary/llvm/unittests/FileCheck/BUILD.gn

+import("//llvm/utils/unittest/unittest.gni")
+
+unittest("FileCheckTests") {
+  deps = [
+    "//llvm/lib/FileCheck",
+    "//llvm/lib/Support",
+  ]
+  sources = [ "FileCheckTest.cpp" ]
+}

llvm/utils/gn/secondary/llvm/unittests/Support/BUILD.gn

sources = [
     "DebugTest.cpp",
     "ELFAttributeParserTest.cpp",
     "EndianStreamTest.cpp",
     "EndianTest.cpp",
     "ErrnoTest.cpp",
     "ErrorOrTest.cpp",
     "ErrorTest.cpp",
     "ExtensibleRTTITest.cpp",
-    "FileCheckTest.cpp",
     "FileCollectorTest.cpp",
     "FileOutputBufferTest.cpp",
     "FileUtilitiesTest.cpp",
     "FormatVariadicTest.cpp",
     "GlobPatternTest.cpp",
     "Host.cpp",
     "IndexedAccessorTest.cpp",
     "ItaniumManglingCanonicalizerTest.cpp",