llvm-project/clang-tools-extra/pp-trace/PPTrace.cpp

233 lines
7.7 KiB
C++

//===--- tools/pp-trace/PPTrace.cpp - Clang preprocessor tracer -----------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements pp-trace, a tool for displaying a textual trace
// of the Clang preprocessor activity. It's based on a derivation of the
// PPCallbacks class, that once registerd with Clang, receives callback calls
// to its virtual members, and outputs the information passed to the callbacks
// in a high-level YAML format.
//
// The pp-trace tool also serves as the basis for a test of the PPCallbacks
// mechanism.
//
// The pp-trace tool supports the following general command line format:
//
// pp-trace [pp-trace options] (source file) [compiler options]
//
// Basically you put the pp-trace options first, then the source file or files,
// and then any options you want to pass to the compiler.
//
// These are the pp-trace options:
//
// -ignore (callback list) Don't display output for a comma-separated
// list of callbacks, i.e.:
// -ignore "FileChanged,InclusionDirective"
//
// -output (file) Output trace to the given file in a YAML
// format, e.g.:
//
// ---
// - Callback: Name
// Argument1: Value1
// Argument2: Value2
// (etc.)
// ...
//
// Future Directions:
//
// 1. Add option opposite to "-ignore" that specifys a comma-separated option
// list of callbacs. Perhaps "-only" or "-exclusive".
//
//===----------------------------------------------------------------------===//
#include "PPCallbacksTracker.h"
#include "clang/AST/ASTConsumer.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/RecursiveASTVisitor.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Driver/Options.h"
#include "clang/Frontend/CompilerInstance.h"
#include "clang/Frontend/FrontendActions.h"
#include "clang/Lex/Preprocessor.h"
#include "clang/Tooling/CompilationDatabase.h"
#include "clang/Tooling/Tooling.h"
#include "llvm/Option/Arg.h"
#include "llvm/Option/ArgList.h"
#include "llvm/Option/OptTable.h"
#include "llvm/Option/Option.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/Path.h"
#include "llvm/Support/ToolOutputFile.h"
#include <algorithm>
#include <fstream>
#include <iterator>
#include <string>
#include <vector>
using namespace clang;
using namespace clang::driver;
using namespace clang::driver::options;
using namespace clang::tooling;
using namespace llvm;
using namespace llvm::opt;
// Options:
// Collect the source files.
cl::list<std::string> SourcePaths(cl::Positional,
cl::desc("<source0> [... <sourceN>]"),
cl::OneOrMore);
// Option to specify a list or one or more callback names to ignore.
cl::opt<std::string> IgnoreCallbacks(
"ignore", cl::init(""),
cl::desc("Ignore callbacks, i.e. \"Callback1, Callback2...\"."));
// Option to specify the trace output file name.
cl::opt<std::string> OutputFileName(
"output", cl::init(""),
cl::desc("Output trace to the given file name or '-' for stdout."));
// Collect all other arguments, which will be passed to the front end.
cl::list<std::string>
CC1Arguments(cl::ConsumeAfter,
cl::desc("<arguments to be passed to front end>..."));
// Frontend action stuff:
// Consumer is responsible for setting up the callbacks.
class PPTraceConsumer : public ASTConsumer {
public:
PPTraceConsumer(SmallSet<std::string, 4> &Ignore,
std::vector<CallbackCall> &CallbackCalls, Preprocessor &PP) {
// PP takes ownership.
PP.addPPCallbacks(llvm::make_unique<PPCallbacksTracker>(Ignore,
CallbackCalls, PP));
}
};
class PPTraceAction : public SyntaxOnlyAction {
public:
PPTraceAction(SmallSet<std::string, 4> &Ignore,
std::vector<CallbackCall> &CallbackCalls)
: Ignore(Ignore), CallbackCalls(CallbackCalls) {}
protected:
std::unique_ptr<clang::ASTConsumer>
CreateASTConsumer(CompilerInstance &CI, StringRef InFile) override {
return llvm::make_unique<PPTraceConsumer>(Ignore, CallbackCalls,
CI.getPreprocessor());
}
private:
SmallSet<std::string, 4> &Ignore;
std::vector<CallbackCall> &CallbackCalls;
};
class PPTraceFrontendActionFactory : public FrontendActionFactory {
public:
PPTraceFrontendActionFactory(SmallSet<std::string, 4> &Ignore,
std::vector<CallbackCall> &CallbackCalls)
: Ignore(Ignore), CallbackCalls(CallbackCalls) {}
virtual PPTraceAction *create() {
return new PPTraceAction(Ignore, CallbackCalls);
}
private:
SmallSet<std::string, 4> &Ignore;
std::vector<CallbackCall> &CallbackCalls;
};
// Output the trace given its data structure and a stream.
int outputPPTrace(std::vector<CallbackCall> &CallbackCalls,
llvm::raw_ostream &OS) {
// Mark start of document.
OS << "---\n";
for (std::vector<CallbackCall>::const_iterator I = CallbackCalls.begin(),
E = CallbackCalls.end();
I != E; ++I) {
const CallbackCall &Callback = *I;
OS << "- Callback: " << Callback.Name << "\n";
for (std::vector<Argument>::const_iterator AI = Callback.Arguments.begin(),
AE = Callback.Arguments.end();
AI != AE; ++AI) {
const Argument &Arg = *AI;
OS << " " << Arg.Name << ": " << Arg.Value << "\n";
}
}
// Mark end of document.
OS << "...\n";
return 0;
}
// Program entry point.
int main(int Argc, const char **Argv) {
// Parse command line.
cl::ParseCommandLineOptions(Argc, Argv, "pp-trace.\n");
// Parse the IgnoreCallbacks list into strings.
SmallVector<StringRef, 32> IgnoreCallbacksStrings;
StringRef(IgnoreCallbacks).split(IgnoreCallbacksStrings, ",",
/*MaxSplit=*/ -1, /*KeepEmpty=*/false);
SmallSet<std::string, 4> Ignore;
for (SmallVector<StringRef, 32>::iterator I = IgnoreCallbacksStrings.begin(),
E = IgnoreCallbacksStrings.end();
I != E; ++I)
Ignore.insert(*I);
// Create the compilation database.
SmallString<256> PathBuf;
sys::fs::current_path(PathBuf);
std::unique_ptr<CompilationDatabase> Compilations;
Compilations.reset(
new FixedCompilationDatabase(Twine(PathBuf), CC1Arguments));
// Store the callback trace information here.
std::vector<CallbackCall> CallbackCalls;
// Create the tool and run the compilation.
ClangTool Tool(*Compilations, SourcePaths);
PPTraceFrontendActionFactory Factory(Ignore, CallbackCalls);
int HadErrors = Tool.run(&Factory);
// If we had errors, exit early.
if (HadErrors)
return HadErrors;
// Do the output.
if (!OutputFileName.size()) {
HadErrors = outputPPTrace(CallbackCalls, llvm::outs());
} else {
// Set up output file.
std::error_code EC;
llvm::tool_output_file Out(OutputFileName, EC, llvm::sys::fs::F_Text);
if (EC) {
llvm::errs() << "pp-trace: error creating " << OutputFileName << ":"
<< EC.message() << "\n";
return 1;
}
HadErrors = outputPPTrace(CallbackCalls, Out.os());
// Tell tool_output_file that we want to keep the file.
if (HadErrors == 0)
Out.keep();
}
return HadErrors;
}