llvm/tools/llvm-tli-checker/llvm-tli-checker.cpp - llvm-project - Git at Google

 //===-- llvm-tli-checker.cpp - Compare TargetLibraryInfo to SDK libraries -===//
 //
 // 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/ADT/SmallString.h"
 #include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/Triple.h"
 #include "llvm/Analysis/TargetLibraryInfo.h"
 #include "llvm/Config/llvm-config.h"
 #include "llvm/Demangle/Demangle.h"
 #include "llvm/Object/Archive.h"
 #include "llvm/Object/ELFObjectFile.h"
 #include "llvm/Option/ArgList.h"
 #include "llvm/Option/Option.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/InitLLVM.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/WithColor.h"

 using namespace llvm;
 using namespace llvm::object;

 // Command-line option boilerplate.
 namespace {
 enum ID {
   OPT_INVALID = 0, // This is not an option ID.
 #define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM,  \
                HELPTEXT, METAVAR, VALUES)                                      \
   OPT_##ID,
 #include "Opts.inc"
 #undef OPTION
 };

 #define PREFIX(NAME, VALUE) const char *const NAME[] = VALUE;
 #include "Opts.inc"
 #undef PREFIX

 const opt::OptTable::Info InfoTable[] = {
 #define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM,  \
                HELPTEXT, METAVAR, VALUES)                                      \
   {                                                                            \
       PREFIX,      NAME,      HELPTEXT,                                        \
       METAVAR,     OPT_##ID,  opt::Option::KIND##Class,                        \
       PARAM,       FLAGS,     OPT_##GROUP,                                     \
       OPT_##ALIAS, ALIASARGS, VALUES},
 #include "Opts.inc"
 #undef OPTION
 };

 class TLICheckerOptTable : public opt::OptTable {
 public:
   TLICheckerOptTable() : OptTable(InfoTable) {}
 };
 } // namespace

 // We have three levels of reporting.
 enum class ReportKind {
   Error,       // For argument parsing errors.
   Summary,     // Report counts but not details.
   Discrepancy, // Report where TLI and the library differ.
   Full         // Report for every known-to-TLI function.
 };

 // Most of the ObjectFile interfaces return an Expected<T>, so make it easy
 // to ignore those.
 template <typename T> T unwrapIgnoreError(Expected<T> E) {
   if (E)
     return std::move(*E);
   // Sink the error and return a nothing value.
   consumeError(E.takeError());
   return T();
 }

 static void fail(const Twine &Message) {
   WithColor::error() << Message << '\n';
   exit(EXIT_FAILURE);
 }

 // Some problem occurred with an archive member; complain and continue.
 static void reportArchiveChildIssue(const object::Archive::Child &C, int Index,
                                     StringRef ArchiveFilename) {
   // First get the member name.
   std::string ChildName;
   Expected<StringRef> NameOrErr = C.getName();
   if (NameOrErr)
     ChildName = std::string(NameOrErr.get());
   else {
     // Ignore the name-fetch error, just report the index.
     consumeError(NameOrErr.takeError());
     ChildName = "<file index: " + std::to_string(Index) + ">";
   }

   WithColor::warning() << ArchiveFilename << "(" << ChildName
                        << "): member is not usable\n";
 }

 // Return Name, and if Name is mangled, append "aka" and the demangled name.
 static std::string PrintableName(StringRef Name) {
   std::string OutputName = "'";
   OutputName += Name;
   OutputName += "'";
   if (Name.startswith("_Z") || Name.startswith("??")) {
     OutputName += " aka ";
     OutputName += demangle(Name.str());
   }
   return OutputName;
 }

 // Store all the names that TargetLibraryInfo knows about; the bool indicates
 // whether TLI has it marked as "available" for the target of interest.
 // This is a vector to preserve the sorted order for better reporting.
 struct TLINameList : std::vector<std::pair<StringRef, bool>> {
   // Record all the TLI info in the vector.
   void initialize(StringRef TargetTriple);
   // Print out what we found.
   void dump();
 };
 TLINameList TLINames;

 void TLINameList::initialize(StringRef TargetTriple) {
   Triple T(TargetTriple);
   TargetLibraryInfoImpl TLII(T);
   TargetLibraryInfo TLI(TLII);

   reserve(LibFunc::NumLibFuncs);
   size_t NumAvailable = 0;
   for (unsigned FI = 0; FI != LibFunc::NumLibFuncs; ++FI) {
     LibFunc LF = (LibFunc)FI;
     bool Available = TLI.has(LF);
     // getName returns names only for available funcs.
     TLII.setAvailable(LF);
     emplace_back(TLI.getName(LF), Available);
     if (Available)
       ++NumAvailable;
   }
   outs() << "TLI knows " << LibFunc::NumLibFuncs << " symbols, " << NumAvailable
          << " available for '" << TargetTriple << "'\n";
 }

 void TLINameList::dump() {
   // Assume this gets called after initialize(), so we have the above line of
   // output as a header.  So, for example, no need to repeat the triple.
   for (auto &TLIName : TLINames) {
     outs() << (TLIName.second ? "    " : "not ")
            << "available: " << PrintableName(TLIName.first) << '\n';
   }
 }

 // Store all the exported symbol names we found in the input libraries.
 // We use a map to get hashed lookup speed; the bool is meaningless.
 class SDKNameMap : public StringMap<bool> {
   void populateFromObject(ObjectFile *O);
   void populateFromArchive(Archive *A);

 public:
   void populateFromFile(StringRef LibDir, StringRef LibName);
 };
 SDKNameMap SDKNames;

 // Given an ObjectFile, extract the global function symbols.
 void SDKNameMap::populateFromObject(ObjectFile *O) {
   // FIXME: Support COFF.
   if (!O->isELF()) {
     WithColor::warning() << "Only ELF-format files are supported\n";
     return;
   }
   auto *ELF = cast<const ELFObjectFileBase>(O);

   for (auto I = ELF->getDynamicSymbolIterators().begin();
        I != ELF->getDynamicSymbolIterators().end(); ++I) {
     // We want only global function symbols.
     SymbolRef::Type Type = unwrapIgnoreError(I->getType());
     uint32_t Flags = unwrapIgnoreError(I->getFlags());
     StringRef Name = unwrapIgnoreError(I->getName());
     if (Type == SymbolRef::ST_Function && (Flags & SymbolRef::SF_Global))
       insert({Name, true});
   }
 }

 // Unpack an archive and populate from the component object files.
 // This roughly imitates dumpArchive() from llvm-objdump.cpp.
 void SDKNameMap::populateFromArchive(Archive *A) {
   Error Err = Error::success();
   int Index = -1;
   for (auto &C : A->children(Err)) {
     ++Index;
     Expected<std::unique_ptr<object::Binary>> ChildOrErr = C.getAsBinary();
     if (!ChildOrErr) {
       if (auto E = isNotObjectErrorInvalidFileType(ChildOrErr.takeError())) {
         // Issue a generic warning.
         consumeError(std::move(E));
         reportArchiveChildIssue(C, Index, A->getFileName());
       }
       continue;
     }
     if (ObjectFile *O = dyn_cast<ObjectFile>(&*ChildOrErr.get()))
       populateFromObject(O);
     // Ignore non-object archive members.
   }
   if (Err)
     WithColor::defaultErrorHandler(std::move(Err));
 }

 // Unpack a library file and extract the global function names.
 void SDKNameMap::populateFromFile(StringRef LibDir, StringRef LibName) {
   // Pick an arbitrary but reasonable default size.
   SmallString<255> Filepath(LibDir);
   sys::path::append(Filepath, LibName);
   if (!sys::fs::exists(Filepath)) {
     WithColor::warning() << "Could not find '" << StringRef(Filepath) << "'\n";
     return;
   }
   outs() << "\nLooking for symbols in '" << StringRef(Filepath) << "'\n";
   auto ExpectedBinary = createBinary(Filepath);
   if (!ExpectedBinary) {
     // FIXME: Report this better.
     WithColor::defaultWarningHandler(ExpectedBinary.takeError());
     return;
   }
   OwningBinary<Binary> OBinary = std::move(*ExpectedBinary);
   Binary &Binary = *OBinary.getBinary();
   size_t Precount = size();
   if (Archive *A = dyn_cast<Archive>(&Binary))
     populateFromArchive(A);
   else if (ObjectFile *O = dyn_cast<ObjectFile>(&Binary))
     populateFromObject(O);
   else {
     WithColor::warning() << "Not an Archive or ObjectFile: '"
                          << StringRef(Filepath) << "'\n";
     return;
   }
   if (Precount == size())
     WithColor::warning() << "No symbols found in '" << StringRef(Filepath)
                          << "'\n";
   else
     outs() << "Found " << size() - Precount << " global function symbols in '"
            << StringRef(Filepath) << "'\n";
 }

 int main(int argc, char *argv[]) {
   InitLLVM X(argc, argv);
   BumpPtrAllocator A;
   StringSaver Saver(A);
   TLICheckerOptTable Tbl;
   opt::InputArgList Args = Tbl.parseArgs(argc, argv, OPT_UNKNOWN, Saver,
                                          [&](StringRef Msg) { fail(Msg); });

   if (Args.hasArg(OPT_help)) {
     std::string Usage(argv[0]);
     Usage += " [options] library-file [library-file...]";
     Tbl.printHelp(outs(), Usage.c_str(),
                   "LLVM TargetLibraryInfo versus SDK checker");
     outs() << "\nPass @FILE as argument to read options or library names from "
               "FILE.\n";
     return 0;
   }

   TLINames.initialize(Args.getLastArgValue(OPT_triple_EQ));

   // --dump-tli doesn't require any input files.
   if (Args.hasArg(OPT_dump_tli)) {
     TLINames.dump();
     return 0;
   }

   std::vector<std::string> LibList = Args.getAllArgValues(OPT_INPUT);
   if (LibList.empty()) {
     WithColor::error() << "No input files\n";
     exit(EXIT_FAILURE);
   }
   StringRef LibDir = Args.getLastArgValue(OPT_libdir_EQ);
   bool SeparateMode = Args.hasArg(OPT_separate);

   ReportKind ReportLevel =
       SeparateMode ? ReportKind::Summary : ReportKind::Discrepancy;
   if (const opt::Arg *A = Args.getLastArg(OPT_report_EQ)) {
     ReportLevel = StringSwitch<ReportKind>(A->getValue())
                       .Case("summary", ReportKind::Summary)
                       .Case("discrepancy", ReportKind::Discrepancy)
                       .Case("full", ReportKind::Full)
                       .Default(ReportKind::Error);
     if (ReportLevel == ReportKind::Error) {
       WithColor::error() << "invalid option for --report: " << A->getValue();
       exit(EXIT_FAILURE);
     }
   }

   for (size_t I = 0; I < LibList.size(); ++I) {
     // In SeparateMode we report on input libraries individually; otherwise
     // we do one big combined search.  Reading to the end of LibList here
     // will cause the outer while loop to terminate cleanly.
     if (SeparateMode) {
       SDKNames.clear();
       SDKNames.populateFromFile(LibDir, LibList[I]);
       if (SDKNames.empty())
         continue;
     } else {
       do
         SDKNames.populateFromFile(LibDir, LibList[I]);
       while (++I < LibList.size());
       if (SDKNames.empty()) {
         WithColor::error() << "NO symbols found!\n";
         break;
       }
       outs() << "Found a grand total of " << SDKNames.size()
              << " library symbols\n";
     }
     unsigned TLIdoesSDKdoesnt = 0;
     unsigned TLIdoesntSDKdoes = 0;
     unsigned TLIandSDKboth = 0;
     unsigned TLIandSDKneither = 0;
     for (auto &TLIName : TLINames) {
       bool TLIHas = TLIName.second;
       bool SDKHas = SDKNames.count(TLIName.first) == 1;
       int Which = int(TLIHas) * 2 + int(SDKHas);
       switch (Which) {
       case 0: ++TLIandSDKneither; break;
       case 1: ++TLIdoesntSDKdoes; break;
       case 2: ++TLIdoesSDKdoesnt; break;
       case 3: ++TLIandSDKboth;    break;
       }
       // If the results match, report only if user requested a full report.
       ReportKind Threshold =
           TLIHas == SDKHas ? ReportKind::Full : ReportKind::Discrepancy;
       if (Threshold <= ReportLevel) {
         constexpr char YesNo[2][4] = {"no ", "yes"};
         constexpr char Indicator[4][3] = {"!!", ">>", "<<", "=="};
         outs() << Indicator[Which] << " TLI " << YesNo[TLIHas] << " SDK "
                << YesNo[SDKHas] << ": " << PrintableName(TLIName.first) << '\n';
       }
     }

     assert(TLIandSDKboth + TLIandSDKneither + TLIdoesSDKdoesnt +
                TLIdoesntSDKdoes ==
            LibFunc::NumLibFuncs);
     outs() << "<< Total TLI yes SDK no:  " << TLIdoesSDKdoesnt
            << "\n>> Total TLI no  SDK yes: " << TLIdoesntSDKdoes
            << "\n== Total TLI yes SDK yes: " << TLIandSDKboth;
     if (TLIandSDKboth == 0) {
       outs() << " *** NO TLI SYMBOLS FOUND";
       if (SeparateMode)
         outs() << " in '" << LibList[I] << "'";
     }
     outs() << '\n';

     if (!SeparateMode) {
       if (TLIdoesSDKdoesnt == 0 && TLIdoesntSDKdoes == 0)
         outs() << "PASS: LLVM TLI matched SDK libraries successfully.\n";
       else
         outs() << "FAIL: LLVM TLI doesn't match SDK libraries.\n";
     }
   }
 }
	//===-- llvm-tli-checker.cpp - Compare TargetLibraryInfo to SDK libraries -===//
	//
	// 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/ADT/SmallString.h"
	#include "llvm/ADT/StringMap.h"
	#include "llvm/ADT/Triple.h"
	#include "llvm/Analysis/TargetLibraryInfo.h"
	#include "llvm/Config/llvm-config.h"
	#include "llvm/Demangle/Demangle.h"
	#include "llvm/Object/Archive.h"
	#include "llvm/Object/ELFObjectFile.h"
	#include "llvm/Option/ArgList.h"
	#include "llvm/Option/Option.h"
	#include "llvm/Support/FileSystem.h"
	#include "llvm/Support/InitLLVM.h"
	#include "llvm/Support/Path.h"
	#include "llvm/Support/WithColor.h"

	using namespace llvm;
	using namespace llvm::object;

	// Command-line option boilerplate.
	namespace {
	enum ID {
	OPT_INVALID = 0, // This is not an option ID.
	#define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM, \
	HELPTEXT, METAVAR, VALUES) \
	OPT_##ID,
	#include "Opts.inc"
	#undef OPTION
	};

	#define PREFIX(NAME, VALUE) const char *const NAME[] = VALUE;
	#include "Opts.inc"
	#undef PREFIX

	const opt::OptTable::Info InfoTable[] = {
	#define OPTION(PREFIX, NAME, ID, KIND, GROUP, ALIAS, ALIASARGS, FLAGS, PARAM, \
	HELPTEXT, METAVAR, VALUES) \
	{ \
	PREFIX, NAME, HELPTEXT, \
	METAVAR, OPT_##ID, opt::Option::KIND##Class, \
	PARAM, FLAGS, OPT_##GROUP, \
	OPT_##ALIAS, ALIASARGS, VALUES},
	#include "Opts.inc"
	#undef OPTION
	};

	class TLICheckerOptTable : public opt::OptTable {
	public:
	TLICheckerOptTable() : OptTable(InfoTable) {}
	};
	} // namespace

	// We have three levels of reporting.
	enum class ReportKind {
	Error, // For argument parsing errors.
	Summary, // Report counts but not details.
	Discrepancy, // Report where TLI and the library differ.
	Full // Report for every known-to-TLI function.
	};

	// Most of the ObjectFile interfaces return an Expected<T>, so make it easy
	// to ignore those.
	template <typename T> T unwrapIgnoreError(Expected<T> E) {
	if (E)
	return std::move(*E);
	// Sink the error and return a nothing value.
	consumeError(E.takeError());
	return T();
	}

	static void fail(const Twine &Message) {
	WithColor::error() << Message << '\n';
	exit(EXIT_FAILURE);
	}

	// Some problem occurred with an archive member; complain and continue.
	static void reportArchiveChildIssue(const object::Archive::Child &C, int Index,
	StringRef ArchiveFilename) {
	// First get the member name.
	std::string ChildName;
	Expected<StringRef> NameOrErr = C.getName();
	if (NameOrErr)
	ChildName = std::string(NameOrErr.get());
	else {
	// Ignore the name-fetch error, just report the index.
	consumeError(NameOrErr.takeError());
	ChildName = "<file index: " + std::to_string(Index) + ">";
	}

	WithColor::warning() << ArchiveFilename << "(" << ChildName
	<< "): member is not usable\n";
	}

	// Return Name, and if Name is mangled, append "aka" and the demangled name.
	static std::string PrintableName(StringRef Name) {
	std::string OutputName = "'";
	OutputName += Name;
	OutputName += "'";
	if (Name.startswith("_Z") \|\| Name.startswith("??")) {
	OutputName += " aka ";
	OutputName += demangle(Name.str());
	}
	return OutputName;
	}

	// Store all the names that TargetLibraryInfo knows about; the bool indicates
	// whether TLI has it marked as "available" for the target of interest.
	// This is a vector to preserve the sorted order for better reporting.
	struct TLINameList : std::vector<std::pair<StringRef, bool>> {
	// Record all the TLI info in the vector.
	void initialize(StringRef TargetTriple);
	// Print out what we found.
	void dump();
	};
	TLINameList TLINames;

	void TLINameList::initialize(StringRef TargetTriple) {
	Triple T(TargetTriple);
	TargetLibraryInfoImpl TLII(T);
	TargetLibraryInfo TLI(TLII);

	reserve(LibFunc::NumLibFuncs);
	size_t NumAvailable = 0;
	for (unsigned FI = 0; FI != LibFunc::NumLibFuncs; ++FI) {
	LibFunc LF = (LibFunc)FI;
	bool Available = TLI.has(LF);
	// getName returns names only for available funcs.
	TLII.setAvailable(LF);
	emplace_back(TLI.getName(LF), Available);
	if (Available)
	++NumAvailable;
	}
	outs() << "TLI knows " << LibFunc::NumLibFuncs << " symbols, " << NumAvailable
	<< " available for '" << TargetTriple << "'\n";
	}

	void TLINameList::dump() {
	// Assume this gets called after initialize(), so we have the above line of
	// output as a header. So, for example, no need to repeat the triple.
	for (auto &TLIName : TLINames) {
	outs() << (TLIName.second ? " " : "not ")
	<< "available: " << PrintableName(TLIName.first) << '\n';
	}
	}

	// Store all the exported symbol names we found in the input libraries.
	// We use a map to get hashed lookup speed; the bool is meaningless.
	class SDKNameMap : public StringMap<bool> {
	void populateFromObject(ObjectFile *O);
	void populateFromArchive(Archive *A);

	public:
	void populateFromFile(StringRef LibDir, StringRef LibName);
	};
	SDKNameMap SDKNames;

	// Given an ObjectFile, extract the global function symbols.
	void SDKNameMap::populateFromObject(ObjectFile *O) {
	// FIXME: Support COFF.
	if (!O->isELF()) {
	WithColor::warning() << "Only ELF-format files are supported\n";
	return;
	}
	auto *ELF = cast<const ELFObjectFileBase>(O);

	for (auto I = ELF->getDynamicSymbolIterators().begin();
	I != ELF->getDynamicSymbolIterators().end(); ++I) {
	// We want only global function symbols.
	SymbolRef::Type Type = unwrapIgnoreError(I->getType());
	uint32_t Flags = unwrapIgnoreError(I->getFlags());
	StringRef Name = unwrapIgnoreError(I->getName());
	if (Type == SymbolRef::ST_Function && (Flags & SymbolRef::SF_Global))
	insert({Name, true});
	}
	}

	// Unpack an archive and populate from the component object files.
	// This roughly imitates dumpArchive() from llvm-objdump.cpp.
	void SDKNameMap::populateFromArchive(Archive *A) {
	Error Err = Error::success();
	int Index = -1;
	for (auto &C : A->children(Err)) {
	++Index;
	Expected<std::unique_ptr<object::Binary>> ChildOrErr = C.getAsBinary();
	if (!ChildOrErr) {
	if (auto E = isNotObjectErrorInvalidFileType(ChildOrErr.takeError())) {
	// Issue a generic warning.
	consumeError(std::move(E));
	reportArchiveChildIssue(C, Index, A->getFileName());
	}
	continue;
	}
	if (ObjectFile O = dyn_cast<ObjectFile>(&ChildOrErr.get()))
	populateFromObject(O);
	// Ignore non-object archive members.
	}
	if (Err)
	WithColor::defaultErrorHandler(std::move(Err));
	}

	// Unpack a library file and extract the global function names.
	void SDKNameMap::populateFromFile(StringRef LibDir, StringRef LibName) {
	// Pick an arbitrary but reasonable default size.
	SmallString<255> Filepath(LibDir);
	sys::path::append(Filepath, LibName);
	if (!sys::fs::exists(Filepath)) {
	WithColor::warning() << "Could not find '" << StringRef(Filepath) << "'\n";
	return;
	}
	outs() << "\nLooking for symbols in '" << StringRef(Filepath) << "'\n";
	auto ExpectedBinary = createBinary(Filepath);
	if (!ExpectedBinary) {
	// FIXME: Report this better.
	WithColor::defaultWarningHandler(ExpectedBinary.takeError());
	return;
	}
	OwningBinary<Binary> OBinary = std::move(*ExpectedBinary);
	Binary &Binary = *OBinary.getBinary();
	size_t Precount = size();
	if (Archive *A = dyn_cast<Archive>(&Binary))
	populateFromArchive(A);
	else if (ObjectFile *O = dyn_cast<ObjectFile>(&Binary))
	populateFromObject(O);
	else {
	WithColor::warning() << "Not an Archive or ObjectFile: '"
	<< StringRef(Filepath) << "'\n";
	return;
	}
	if (Precount == size())
	WithColor::warning() << "No symbols found in '" << StringRef(Filepath)
	<< "'\n";
	else
	outs() << "Found " << size() - Precount << " global function symbols in '"
	<< StringRef(Filepath) << "'\n";
	}

	int main(int argc, char *argv[]) {
	InitLLVM X(argc, argv);
	BumpPtrAllocator A;
	StringSaver Saver(A);
	TLICheckerOptTable Tbl;
	opt::InputArgList Args = Tbl.parseArgs(argc, argv, OPT_UNKNOWN, Saver,
	[&](StringRef Msg) { fail(Msg); });

	if (Args.hasArg(OPT_help)) {
	std::string Usage(argv[0]);
	Usage += " [options] library-file [library-file...]";
	Tbl.printHelp(outs(), Usage.c_str(),
	"LLVM TargetLibraryInfo versus SDK checker");
	outs() << "\nPass @FILE as argument to read options or library names from "
	"FILE.\n";
	return 0;
	}

	TLINames.initialize(Args.getLastArgValue(OPT_triple_EQ));

	// --dump-tli doesn't require any input files.
	if (Args.hasArg(OPT_dump_tli)) {
	TLINames.dump();
	return 0;
	}

	std::vector<std::string> LibList = Args.getAllArgValues(OPT_INPUT);
	if (LibList.empty()) {
	WithColor::error() << "No input files\n";
	exit(EXIT_FAILURE);
	}
	StringRef LibDir = Args.getLastArgValue(OPT_libdir_EQ);
	bool SeparateMode = Args.hasArg(OPT_separate);

	ReportKind ReportLevel =
	SeparateMode ? ReportKind::Summary : ReportKind::Discrepancy;
	if (const opt::Arg *A = Args.getLastArg(OPT_report_EQ)) {
	ReportLevel = StringSwitch<ReportKind>(A->getValue())
	.Case("summary", ReportKind::Summary)
	.Case("discrepancy", ReportKind::Discrepancy)
	.Case("full", ReportKind::Full)
	.Default(ReportKind::Error);
	if (ReportLevel == ReportKind::Error) {
	WithColor::error() << "invalid option for --report: " << A->getValue();
	exit(EXIT_FAILURE);
	}
	}

	for (size_t I = 0; I < LibList.size(); ++I) {
	// In SeparateMode we report on input libraries individually; otherwise
	// we do one big combined search. Reading to the end of LibList here
	// will cause the outer while loop to terminate cleanly.
	if (SeparateMode) {
	SDKNames.clear();
	SDKNames.populateFromFile(LibDir, LibList[I]);
	if (SDKNames.empty())
	continue;
	} else {
	do
	SDKNames.populateFromFile(LibDir, LibList[I]);
	while (++I < LibList.size());
	if (SDKNames.empty()) {
	WithColor::error() << "NO symbols found!\n";
	break;
	}
	outs() << "Found a grand total of " << SDKNames.size()
	<< " library symbols\n";
	}
	unsigned TLIdoesSDKdoesnt = 0;
	unsigned TLIdoesntSDKdoes = 0;
	unsigned TLIandSDKboth = 0;
	unsigned TLIandSDKneither = 0;
	for (auto &TLIName : TLINames) {
	bool TLIHas = TLIName.second;
	bool SDKHas = SDKNames.count(TLIName.first) == 1;
	int Which = int(TLIHas) * 2 + int(SDKHas);
	switch (Which) {
	case 0: ++TLIandSDKneither; break;
	case 1: ++TLIdoesntSDKdoes; break;
	case 2: ++TLIdoesSDKdoesnt; break;
	case 3: ++TLIandSDKboth; break;
	}
	// If the results match, report only if user requested a full report.
	ReportKind Threshold =
	TLIHas == SDKHas ? ReportKind::Full : ReportKind::Discrepancy;
	if (Threshold <= ReportLevel) {
	constexpr char YesNo[2][4] = {"no ", "yes"};
	constexpr char Indicator[4][3] = {"!!", ">>", "<<", "=="};
	outs() << Indicator[Which] << " TLI " << YesNo[TLIHas] << " SDK "
	<< YesNo[SDKHas] << ": " << PrintableName(TLIName.first) << '\n';
	}
	}

	assert(TLIandSDKboth + TLIandSDKneither + TLIdoesSDKdoesnt +
	TLIdoesntSDKdoes ==
	LibFunc::NumLibFuncs);
	outs() << "<< Total TLI yes SDK no: " << TLIdoesSDKdoesnt
	<< "\n>> Total TLI no SDK yes: " << TLIdoesntSDKdoes
	<< "\n== Total TLI yes SDK yes: " << TLIandSDKboth;
	if (TLIandSDKboth == 0) {
	outs() << " *** NO TLI SYMBOLS FOUND";
	if (SeparateMode)
	outs() << " in '" << LibList[I] << "'";
	}
	outs() << '\n';

	if (!SeparateMode) {
	if (TLIdoesSDKdoesnt == 0 && TLIdoesntSDKdoes == 0)
	outs() << "PASS: LLVM TLI matched SDK libraries successfully.\n";
	else
	outs() << "FAIL: LLVM TLI doesn't match SDK libraries.\n";
	}
	}
	}