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/*
* Copyright 2016 WebAssembly Community Group participants
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
//
// A WebAssembly optimizer, loads code, optionally runs passes on it,
// then writes it.
//
#include <memory>
#include "pass.h"
#include "support/command-line.h"
#include "support/file.h"
#include "wasm-printing.h"
#include "wasm-s-parser.h"
#include "wasm-validator.h"
#include "wasm-io.h"
#include "wasm-interpreter.h"
#include "wasm-binary.h"
#include "shell-interface.h"
#include "optimization-options.h"
#include "execution-results.h"
#include "fuzzing.h"
#include "js-wrapper.h"
#include "spec-wrapper.h"
using namespace wasm;
// runs a command and returns its output TODO: portability, return code checking
std::string runCommand(std::string command) {
#ifdef __linux__
std::string output;
const int MAX_BUFFER = 1024;
char buffer[MAX_BUFFER];
FILE *stream = popen(command.c_str(), "r");
while (fgets(buffer, MAX_BUFFER, stream) != NULL) {
output.append(buffer);
}
pclose(stream);
return output;
#else
Fatal() << "TODO: portability for wasm-opt runCommand";
#endif
}
//
// main
//
int main(int argc, const char* argv[]) {
Name entry;
bool emitBinary = true;
bool debugInfo = false;
bool fuzzExec = false;
bool fuzzBinary = false;
std::string extraFuzzCommand;
bool translateToFuzz = false;
bool fuzzPasses = false;
std::string emitJSWrapper;
std::string emitSpecWrapper;
OptimizationOptions options("wasm-opt", "Read, write, and optimize files");
options
.add("--output", "-o", "Output file (stdout if not specified)",
Options::Arguments::One,
[](Options* o, const std::string& argument) {
o->extra["output"] = argument;
Colors::disable();
})
.add("--emit-text", "-S", "Emit text instead of binary for the output file",
Options::Arguments::Zero,
[&](Options *o, const std::string& argument) { emitBinary = false; })
.add("--debuginfo", "-g", "Emit names section and debug info",
Options::Arguments::Zero,
[&](Options *o, const std::string& arguments) { debugInfo = true; })
.add("--fuzz-exec", "-fe", "Execute functions before and after optimization, helping fuzzing find bugs",
Options::Arguments::Zero,
[&](Options *o, const std::string& arguments) { fuzzExec = true; })
.add("--fuzz-binary", "-fb", "Convert to binary and back after optimizations and before fuzz-exec, helping fuzzing find binary format bugs",
Options::Arguments::Zero,
[&](Options *o, const std::string& arguments) { fuzzBinary = true; })
.add("--extra-fuzz-command", "-efc", "An extra command to run on the output before and after optimizing. The output is compared between the two, and an error occurs if they are not equal",
Options::Arguments::One,
[&](Options *o, const std::string& arguments) { extraFuzzCommand = arguments; })
.add("--translate-to-fuzz", "-ttf", "Translate the input into a valid wasm module *somehow*, useful for fuzzing",
Options::Arguments::Zero,
[&](Options *o, const std::string& arguments) { translateToFuzz = true; })
.add("--fuzz-passes", "-fp", "Pick a random set of passes to run, useful for fuzzing. this depends on translate-to-fuzz (it picks the passes from the input)",
Options::Arguments::Zero,
[&](Options *o, const std::string& arguments) { fuzzPasses = true; })
.add("--emit-js-wrapper", "-ejw", "Emit a JavaScript wrapper file that can run the wasm with some test values, useful for fuzzing",
Options::Arguments::One,
[&](Options *o, const std::string& arguments) { emitJSWrapper = arguments; })
.add("--emit-spec-wrapper", "-esw", "Emit a wasm spec interpreter wrapper file that can run the wasm with some test values, useful for fuzzing",
Options::Arguments::One,
[&](Options *o, const std::string& arguments) { emitSpecWrapper = arguments; })
.add_positional("INFILE", Options::Arguments::One,
[](Options* o, const std::string& argument) {
o->extra["infile"] = argument;
});
options.parse(argc, argv);
Module wasm;
// It should be safe to just always enable atomics in wasm-opt, because we
// don't expect any passes to accidentally generate atomic ops
FeatureSet features = Feature::Atomics;
if (options.debug) std::cerr << "reading...\n";
if (!translateToFuzz) {
ModuleReader reader;
reader.setDebug(options.debug);
try {
reader.read(options.extra["infile"], wasm);
} catch (ParseException& p) {
p.dump(std::cerr);
Fatal() << "error in parsing input";
} catch (std::bad_alloc& b) {
Fatal() << "error in building module, std::bad_alloc (possibly invalid request for silly amounts of memory)";
}
if (options.passOptions.validate) {
if (!WasmValidator().validate(wasm, features)) {
WasmPrinter::printModule(&wasm);
Fatal() << "error in validating input";
}
}
} else {
// translate-to-fuzz
TranslateToFuzzReader reader(wasm, options.extra["infile"]);
if (fuzzPasses) {
reader.pickPasses(options);
}
reader.build();
if (options.passOptions.validate) {
if (!WasmValidator().validate(wasm, features)) {
WasmPrinter::printModule(&wasm);
std::cerr << "translate-to-fuzz must always generate a valid module";
abort();
}
}
}
ExecutionResults results;
if (fuzzExec) {
results.get(wasm);
}
if (emitJSWrapper.size() > 0) {
std::ofstream outfile;
outfile.open(emitJSWrapper, std::ofstream::out);
outfile << generateJSWrapper(wasm);
outfile.close();
}
if (emitSpecWrapper.size() > 0) {
std::ofstream outfile;
outfile.open(emitSpecWrapper, std::ofstream::out);
outfile << generateSpecWrapper(wasm);
outfile.close();
}
std::string firstOutput;
if (extraFuzzCommand.size() > 0 && options.extra.count("output") > 0) {
if (options.debug) std::cerr << "writing binary before opts, for extra fuzz command..." << std::endl;
ModuleWriter writer;
writer.setDebug(options.debug);
writer.setBinary(emitBinary);
writer.setDebugInfo(debugInfo);
writer.write(wasm, options.extra["output"]);
firstOutput = runCommand(extraFuzzCommand);
std::cout << "[extra-fuzz-command first output:]\n" << firstOutput << '\n';
}
Module* curr = &wasm;
Module other;
if (fuzzExec && fuzzBinary) {
BufferWithRandomAccess buffer(false);
// write the binary
WasmBinaryWriter writer(&wasm, buffer, false);
writer.write();
// read the binary
auto input = buffer.getAsChars();
WasmBinaryBuilder parser(other, input, false);
parser.read();
if (options.passOptions.validate) {
bool valid = WasmValidator().validate(other, features);
if (!valid) {
WasmPrinter::printModule(&other);
}
assert(valid);
}
curr = &other;
}
if (options.runningPasses()) {
if (options.debug) std::cerr << "running passes...\n";
options.runPasses(*curr);
if (options.passOptions.validate) {
bool valid = WasmValidator().validate(*curr, features);
if (!valid) {
WasmPrinter::printModule(&*curr);
}
assert(valid);
}
}
if (fuzzExec) {
results.check(*curr);
}
if (options.extra.count("output") > 0) {
if (options.debug) std::cerr << "writing..." << std::endl;
ModuleWriter writer;
writer.setDebug(options.debug);
writer.setBinary(emitBinary);
writer.setDebugInfo(debugInfo);
writer.write(*curr, options.extra["output"]);
if (extraFuzzCommand.size() > 0) {
auto secondOutput = runCommand(extraFuzzCommand);
std::cout << "[extra-fuzz-command second output:]\n" << firstOutput << '\n';
if (firstOutput != secondOutput) {
std::cerr << "extra fuzz command output differs\n";
abort();
}
}
}
}
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