1 //===- ExecutionDriver.cpp - Allow execution of LLVM program --------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file contains code used to execute the program utilizing one of the
11 // various ways of running LLVM bitcode.
12 //
13 //===----------------------------------------------------------------------===//
14
15 #include "BugDriver.h"
16 #include "ToolRunner.h"
17 #include "llvm/Support/CommandLine.h"
18 #include "llvm/Support/Debug.h"
19 #include "llvm/Support/FileUtilities.h"
20 #include "llvm/Support/SystemUtils.h"
21 #include "llvm/Support/raw_ostream.h"
22 #include <fstream>
23
24 using namespace llvm;
25
26 namespace {
27 // OutputType - Allow the user to specify the way code should be run, to test
28 // for miscompilation.
29 //
30 enum OutputType {
31 AutoPick, RunLLI, RunJIT, RunLLC, RunLLCIA, LLC_Safe, CompileCustom, Custom
32 };
33
34 cl::opt<double>
35 AbsTolerance("abs-tolerance", cl::desc("Absolute error tolerated"),
36 cl::init(0.0));
37 cl::opt<double>
38 RelTolerance("rel-tolerance", cl::desc("Relative error tolerated"),
39 cl::init(0.0));
40
41 cl::opt<OutputType>
42 InterpreterSel(cl::desc("Specify the \"test\" i.e. suspect back-end:"),
43 cl::values(clEnumValN(AutoPick, "auto", "Use best guess"),
44 clEnumValN(RunLLI, "run-int",
45 "Execute with the interpreter"),
46 clEnumValN(RunJIT, "run-jit", "Execute with JIT"),
47 clEnumValN(RunLLC, "run-llc", "Compile with LLC"),
48 clEnumValN(RunLLCIA, "run-llc-ia",
49 "Compile with LLC with integrated assembler"),
50 clEnumValN(LLC_Safe, "llc-safe", "Use LLC for all"),
51 clEnumValN(CompileCustom, "compile-custom",
52 "Use -compile-command to define a command to "
53 "compile the bitcode. Useful to avoid linking."),
54 clEnumValN(Custom, "run-custom",
55 "Use -exec-command to define a command to execute "
56 "the bitcode. Useful for cross-compilation."),
57 clEnumValEnd),
58 cl::init(AutoPick));
59
60 cl::opt<OutputType>
61 SafeInterpreterSel(cl::desc("Specify \"safe\" i.e. known-good backend:"),
62 cl::values(clEnumValN(AutoPick, "safe-auto", "Use best guess"),
63 clEnumValN(RunLLC, "safe-run-llc", "Compile with LLC"),
64 clEnumValN(Custom, "safe-run-custom",
65 "Use -exec-command to define a command to execute "
66 "the bitcode. Useful for cross-compilation."),
67 clEnumValEnd),
68 cl::init(AutoPick));
69
70 cl::opt<std::string>
71 SafeInterpreterPath("safe-path",
72 cl::desc("Specify the path to the \"safe\" backend program"),
73 cl::init(""));
74
75 cl::opt<bool>
76 AppendProgramExitCode("append-exit-code",
77 cl::desc("Append the exit code to the output so it gets diff'd too"),
78 cl::init(false));
79
80 cl::opt<std::string>
81 InputFile("input", cl::init("/dev/null"),
82 cl::desc("Filename to pipe in as stdin (default: /dev/null)"));
83
84 cl::list<std::string>
85 AdditionalSOs("additional-so",
86 cl::desc("Additional shared objects to load "
87 "into executing programs"));
88
89 cl::list<std::string>
90 AdditionalLinkerArgs("Xlinker",
91 cl::desc("Additional arguments to pass to the linker"));
92
93 cl::opt<std::string>
94 CustomCompileCommand("compile-command", cl::init("llc"),
95 cl::desc("Command to compile the bitcode (use with -compile-custom) "
96 "(default: llc)"));
97
98 cl::opt<std::string>
99 CustomExecCommand("exec-command", cl::init("simulate"),
100 cl::desc("Command to execute the bitcode (use with -run-custom) "
101 "(default: simulate)"));
102 }
103
104 namespace llvm {
105 // Anything specified after the --args option are taken as arguments to the
106 // program being debugged.
107 cl::list<std::string>
108 InputArgv("args", cl::Positional, cl::desc("<program arguments>..."),
109 cl::ZeroOrMore, cl::PositionalEatsArgs);
110
111 cl::opt<std::string>
112 OutputPrefix("output-prefix", cl::init("bugpoint"),
113 cl::desc("Prefix to use for outputs (default: 'bugpoint')"));
114 }
115
116 namespace {
117 cl::list<std::string>
118 ToolArgv("tool-args", cl::Positional, cl::desc("<tool arguments>..."),
119 cl::ZeroOrMore, cl::PositionalEatsArgs);
120
121 cl::list<std::string>
122 SafeToolArgv("safe-tool-args", cl::Positional,
123 cl::desc("<safe-tool arguments>..."),
124 cl::ZeroOrMore, cl::PositionalEatsArgs);
125
126 cl::opt<std::string>
127 GCCBinary("gcc", cl::init("gcc"),
128 cl::desc("The gcc binary to use. (default 'gcc')"));
129
130 cl::list<std::string>
131 GCCToolArgv("gcc-tool-args", cl::Positional,
132 cl::desc("<gcc-tool arguments>..."),
133 cl::ZeroOrMore, cl::PositionalEatsArgs);
134 }
135
136 //===----------------------------------------------------------------------===//
137 // BugDriver method implementation
138 //
139
140 /// initializeExecutionEnvironment - This method is used to set up the
141 /// environment for executing LLVM programs.
142 ///
initializeExecutionEnvironment()143 bool BugDriver::initializeExecutionEnvironment() {
144 outs() << "Initializing execution environment: ";
145
146 // Create an instance of the AbstractInterpreter interface as specified on
147 // the command line
148 SafeInterpreter = 0;
149 std::string Message;
150
151 switch (InterpreterSel) {
152 case AutoPick:
153 if (!Interpreter) {
154 InterpreterSel = RunJIT;
155 Interpreter = AbstractInterpreter::createJIT(getToolName(), Message,
156 &ToolArgv);
157 }
158 if (!Interpreter) {
159 InterpreterSel = RunLLC;
160 Interpreter = AbstractInterpreter::createLLC(getToolName(), Message,
161 GCCBinary, &ToolArgv,
162 &GCCToolArgv);
163 }
164 if (!Interpreter) {
165 InterpreterSel = RunLLI;
166 Interpreter = AbstractInterpreter::createLLI(getToolName(), Message,
167 &ToolArgv);
168 }
169 if (!Interpreter) {
170 InterpreterSel = AutoPick;
171 Message = "Sorry, I can't automatically select an interpreter!\n";
172 }
173 break;
174 case RunLLI:
175 Interpreter = AbstractInterpreter::createLLI(getToolName(), Message,
176 &ToolArgv);
177 break;
178 case RunLLC:
179 case RunLLCIA:
180 case LLC_Safe:
181 Interpreter = AbstractInterpreter::createLLC(getToolName(), Message,
182 GCCBinary, &ToolArgv,
183 &GCCToolArgv,
184 InterpreterSel == RunLLCIA);
185 break;
186 case RunJIT:
187 Interpreter = AbstractInterpreter::createJIT(getToolName(), Message,
188 &ToolArgv);
189 break;
190 case CompileCustom:
191 Interpreter =
192 AbstractInterpreter::createCustomCompiler(Message, CustomCompileCommand);
193 break;
194 case Custom:
195 Interpreter =
196 AbstractInterpreter::createCustomExecutor(Message, CustomExecCommand);
197 break;
198 }
199 if (!Interpreter)
200 errs() << Message;
201 else // Display informational messages on stdout instead of stderr
202 outs() << Message;
203
204 std::string Path = SafeInterpreterPath;
205 if (Path.empty())
206 Path = getToolName();
207 std::vector<std::string> SafeToolArgs = SafeToolArgv;
208 switch (SafeInterpreterSel) {
209 case AutoPick:
210 // In "llc-safe" mode, default to using LLC as the "safe" backend.
211 if (!SafeInterpreter &&
212 InterpreterSel == LLC_Safe) {
213 SafeInterpreterSel = RunLLC;
214 SafeToolArgs.push_back("--relocation-model=pic");
215 SafeInterpreter = AbstractInterpreter::createLLC(Path.c_str(), Message,
216 GCCBinary,
217 &SafeToolArgs,
218 &GCCToolArgv);
219 }
220
221 if (!SafeInterpreter &&
222 InterpreterSel != RunLLC &&
223 InterpreterSel != RunJIT) {
224 SafeInterpreterSel = RunLLC;
225 SafeToolArgs.push_back("--relocation-model=pic");
226 SafeInterpreter = AbstractInterpreter::createLLC(Path.c_str(), Message,
227 GCCBinary,
228 &SafeToolArgs,
229 &GCCToolArgv);
230 }
231 if (!SafeInterpreter) {
232 SafeInterpreterSel = AutoPick;
233 Message = "Sorry, I can't automatically select an interpreter!\n";
234 }
235 break;
236 case RunLLC:
237 case RunLLCIA:
238 SafeToolArgs.push_back("--relocation-model=pic");
239 SafeInterpreter = AbstractInterpreter::createLLC(Path.c_str(), Message,
240 GCCBinary, &SafeToolArgs,
241 &GCCToolArgv,
242 SafeInterpreterSel == RunLLCIA);
243 break;
244 case Custom:
245 SafeInterpreter =
246 AbstractInterpreter::createCustomExecutor(Message, CustomExecCommand);
247 break;
248 default:
249 Message = "Sorry, this back-end is not supported by bugpoint as the "
250 "\"safe\" backend right now!\n";
251 break;
252 }
253 if (!SafeInterpreter) { outs() << Message << "\nExiting.\n"; exit(1); }
254
255 gcc = GCC::create(Message, GCCBinary, &GCCToolArgv);
256 if (!gcc) { outs() << Message << "\nExiting.\n"; exit(1); }
257
258 // If there was an error creating the selected interpreter, quit with error.
259 return Interpreter == 0;
260 }
261
262 /// compileProgram - Try to compile the specified module, returning false and
263 /// setting Error if an error occurs. This is used for code generation
264 /// crash testing.
265 ///
compileProgram(Module * M,std::string * Error) const266 void BugDriver::compileProgram(Module *M, std::string *Error) const {
267 // Emit the program to a bitcode file...
268 sys::Path BitcodeFile (OutputPrefix + "-test-program.bc");
269 std::string ErrMsg;
270 if (BitcodeFile.makeUnique(true, &ErrMsg)) {
271 errs() << ToolName << ": Error making unique filename: " << ErrMsg
272 << "\n";
273 exit(1);
274 }
275 if (writeProgramToFile(BitcodeFile.str(), M)) {
276 errs() << ToolName << ": Error emitting bitcode to file '"
277 << BitcodeFile.str() << "'!\n";
278 exit(1);
279 }
280
281 // Remove the temporary bitcode file when we are done.
282 FileRemover BitcodeFileRemover(BitcodeFile.str(), !SaveTemps);
283
284 // Actually compile the program!
285 Interpreter->compileProgram(BitcodeFile.str(), Error, Timeout, MemoryLimit);
286 }
287
288
289 /// executeProgram - This method runs "Program", capturing the output of the
290 /// program to a file, returning the filename of the file. A recommended
291 /// filename may be optionally specified.
292 ///
executeProgram(const Module * Program,std::string OutputFile,std::string BitcodeFile,const std::string & SharedObj,AbstractInterpreter * AI,std::string * Error) const293 std::string BugDriver::executeProgram(const Module *Program,
294 std::string OutputFile,
295 std::string BitcodeFile,
296 const std::string &SharedObj,
297 AbstractInterpreter *AI,
298 std::string *Error) const {
299 if (AI == 0) AI = Interpreter;
300 assert(AI && "Interpreter should have been created already!");
301 bool CreatedBitcode = false;
302 std::string ErrMsg;
303 if (BitcodeFile.empty()) {
304 // Emit the program to a bitcode file...
305 sys::Path uniqueFilename(OutputPrefix + "-test-program.bc");
306 if (uniqueFilename.makeUnique(true, &ErrMsg)) {
307 errs() << ToolName << ": Error making unique filename: "
308 << ErrMsg << "!\n";
309 exit(1);
310 }
311 BitcodeFile = uniqueFilename.str();
312
313 if (writeProgramToFile(BitcodeFile, Program)) {
314 errs() << ToolName << ": Error emitting bitcode to file '"
315 << BitcodeFile << "'!\n";
316 exit(1);
317 }
318 CreatedBitcode = true;
319 }
320
321 // Remove the temporary bitcode file when we are done.
322 sys::Path BitcodePath(BitcodeFile);
323 FileRemover BitcodeFileRemover(BitcodePath.str(),
324 CreatedBitcode && !SaveTemps);
325
326 if (OutputFile.empty()) OutputFile = OutputPrefix + "-execution-output";
327
328 // Check to see if this is a valid output filename...
329 sys::Path uniqueFile(OutputFile);
330 if (uniqueFile.makeUnique(true, &ErrMsg)) {
331 errs() << ToolName << ": Error making unique filename: "
332 << ErrMsg << "\n";
333 exit(1);
334 }
335 OutputFile = uniqueFile.str();
336
337 // Figure out which shared objects to run, if any.
338 std::vector<std::string> SharedObjs(AdditionalSOs);
339 if (!SharedObj.empty())
340 SharedObjs.push_back(SharedObj);
341
342 int RetVal = AI->ExecuteProgram(BitcodeFile, InputArgv, InputFile, OutputFile,
343 Error, AdditionalLinkerArgs, SharedObjs,
344 Timeout, MemoryLimit);
345 if (!Error->empty())
346 return OutputFile;
347
348 if (RetVal == -1) {
349 errs() << "<timeout>";
350 static bool FirstTimeout = true;
351 if (FirstTimeout) {
352 outs() << "\n"
353 "*** Program execution timed out! This mechanism is designed to handle\n"
354 " programs stuck in infinite loops gracefully. The -timeout option\n"
355 " can be used to change the timeout threshold or disable it completely\n"
356 " (with -timeout=0). This message is only displayed once.\n";
357 FirstTimeout = false;
358 }
359 }
360
361 if (AppendProgramExitCode) {
362 std::ofstream outFile(OutputFile.c_str(), std::ios_base::app);
363 outFile << "exit " << RetVal << '\n';
364 outFile.close();
365 }
366
367 // Return the filename we captured the output to.
368 return OutputFile;
369 }
370
371 /// executeProgramSafely - Used to create reference output with the "safe"
372 /// backend, if reference output is not provided.
373 ///
executeProgramSafely(const Module * Program,std::string OutputFile,std::string * Error) const374 std::string BugDriver::executeProgramSafely(const Module *Program,
375 std::string OutputFile,
376 std::string *Error) const {
377 return executeProgram(Program, OutputFile, "", "", SafeInterpreter, Error);
378 }
379
compileSharedObject(const std::string & BitcodeFile,std::string & Error)380 std::string BugDriver::compileSharedObject(const std::string &BitcodeFile,
381 std::string &Error) {
382 assert(Interpreter && "Interpreter should have been created already!");
383 sys::Path OutputFile;
384
385 // Using the known-good backend.
386 GCC::FileType FT = SafeInterpreter->OutputCode(BitcodeFile, OutputFile,
387 Error);
388 if (!Error.empty())
389 return "";
390
391 std::string SharedObjectFile;
392 bool Failure = gcc->MakeSharedObject(OutputFile.str(), FT, SharedObjectFile,
393 AdditionalLinkerArgs, Error);
394 if (!Error.empty())
395 return "";
396 if (Failure)
397 exit(1);
398
399 // Remove the intermediate C file
400 OutputFile.eraseFromDisk();
401
402 return "./" + SharedObjectFile;
403 }
404
405 /// createReferenceFile - calls compileProgram and then records the output
406 /// into ReferenceOutputFile. Returns true if reference file created, false
407 /// otherwise. Note: initializeExecutionEnvironment should be called BEFORE
408 /// this function.
409 ///
createReferenceFile(Module * M,const std::string & Filename)410 bool BugDriver::createReferenceFile(Module *M, const std::string &Filename) {
411 std::string Error;
412 compileProgram(Program, &Error);
413 if (!Error.empty())
414 return false;
415
416 ReferenceOutputFile = executeProgramSafely(Program, Filename, &Error);
417 if (!Error.empty()) {
418 errs() << Error;
419 if (Interpreter != SafeInterpreter) {
420 errs() << "*** There is a bug running the \"safe\" backend. Either"
421 << " debug it (for example with the -run-jit bugpoint option,"
422 << " if JIT is being used as the \"safe\" backend), or fix the"
423 << " error some other way.\n";
424 }
425 return false;
426 }
427 outs() << "\nReference output is: " << ReferenceOutputFile << "\n\n";
428 return true;
429 }
430
431 /// diffProgram - This method executes the specified module and diffs the
432 /// output against the file specified by ReferenceOutputFile. If the output
433 /// is different, 1 is returned. If there is a problem with the code
434 /// generator (e.g., llc crashes), this will set ErrMsg.
435 ///
diffProgram(const Module * Program,const std::string & BitcodeFile,const std::string & SharedObject,bool RemoveBitcode,std::string * ErrMsg) const436 bool BugDriver::diffProgram(const Module *Program,
437 const std::string &BitcodeFile,
438 const std::string &SharedObject,
439 bool RemoveBitcode,
440 std::string *ErrMsg) const {
441 // Execute the program, generating an output file...
442 sys::Path Output(executeProgram(Program, "", BitcodeFile, SharedObject, 0,
443 ErrMsg));
444 if (!ErrMsg->empty())
445 return false;
446
447 std::string Error;
448 bool FilesDifferent = false;
449 if (int Diff = DiffFilesWithTolerance(sys::Path(ReferenceOutputFile),
450 sys::Path(Output.str()),
451 AbsTolerance, RelTolerance, &Error)) {
452 if (Diff == 2) {
453 errs() << "While diffing output: " << Error << '\n';
454 exit(1);
455 }
456 FilesDifferent = true;
457 }
458 else {
459 // Remove the generated output if there are no differences.
460 Output.eraseFromDisk();
461 }
462
463 // Remove the bitcode file if we are supposed to.
464 if (RemoveBitcode)
465 sys::Path(BitcodeFile).eraseFromDisk();
466 return FilesDifferent;
467 }
468
isExecutingJIT()469 bool BugDriver::isExecutingJIT() {
470 return InterpreterSel == RunJIT;
471 }
472
473