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1 //===- opt.cpp - The LLVM Modular Optimizer -------------------------------===//
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 // Optimizations may be specified an arbitrary number of times on the command
11 // line, They are run in the order specified.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "llvm/LLVMContext.h"
16 #include "llvm/Module.h"
17 #include "llvm/PassManager.h"
18 #include "llvm/CallGraphSCCPass.h"
19 #include "llvm/Bitcode/ReaderWriter.h"
20 #include "llvm/Assembly/PrintModulePass.h"
21 #include "llvm/Analysis/DebugInfo.h"
22 #include "llvm/Analysis/Verifier.h"
23 #include "llvm/Analysis/LoopPass.h"
24 #include "llvm/Analysis/RegionPass.h"
25 #include "llvm/Analysis/CallGraph.h"
26 #include "llvm/Target/TargetData.h"
27 #include "llvm/Target/TargetLibraryInfo.h"
28 #include "llvm/Target/TargetMachine.h"
29 #include "llvm/ADT/StringSet.h"
30 #include "llvm/ADT/Triple.h"
31 #include "llvm/Support/PassNameParser.h"
32 #include "llvm/Support/Signals.h"
33 #include "llvm/Support/Debug.h"
34 #include "llvm/Support/IRReader.h"
35 #include "llvm/Support/ManagedStatic.h"
36 #include "llvm/Support/PluginLoader.h"
37 #include "llvm/Support/PrettyStackTrace.h"
38 #include "llvm/Support/SystemUtils.h"
39 #include "llvm/Support/ToolOutputFile.h"
40 #include "llvm/LinkAllPasses.h"
41 #include "llvm/LinkAllVMCore.h"
42 #include "llvm/Transforms/IPO/PassManagerBuilder.h"
43 #include <memory>
44 #include <algorithm>
45 using namespace llvm;
46 
47 // The OptimizationList is automatically populated with registered Passes by the
48 // PassNameParser.
49 //
50 static cl::list<const PassInfo*, bool, PassNameParser>
51 PassList(cl::desc("Optimizations available:"));
52 
53 // Other command line options...
54 //
55 static cl::opt<std::string>
56 InputFilename(cl::Positional, cl::desc("<input bitcode file>"),
57     cl::init("-"), cl::value_desc("filename"));
58 
59 static cl::opt<std::string>
60 OutputFilename("o", cl::desc("Override output filename"),
61                cl::value_desc("filename"));
62 
63 static cl::opt<bool>
64 Force("f", cl::desc("Enable binary output on terminals"));
65 
66 static cl::opt<bool>
67 PrintEachXForm("p", cl::desc("Print module after each transformation"));
68 
69 static cl::opt<bool>
70 NoOutput("disable-output",
71          cl::desc("Do not write result bitcode file"), cl::Hidden);
72 
73 static cl::opt<bool>
74 OutputAssembly("S", cl::desc("Write output as LLVM assembly"));
75 
76 static cl::opt<bool>
77 NoVerify("disable-verify", cl::desc("Do not verify result module"), cl::Hidden);
78 
79 static cl::opt<bool>
80 VerifyEach("verify-each", cl::desc("Verify after each transform"));
81 
82 static cl::opt<bool>
83 StripDebug("strip-debug",
84            cl::desc("Strip debugger symbol info from translation unit"));
85 
86 static cl::opt<bool>
87 DisableInline("disable-inlining", cl::desc("Do not run the inliner pass"));
88 
89 static cl::opt<bool>
90 DisableOptimizations("disable-opt",
91                      cl::desc("Do not run any optimization passes"));
92 
93 static cl::opt<bool>
94 DisableInternalize("disable-internalize",
95                    cl::desc("Do not mark all symbols as internal"));
96 
97 static cl::opt<bool>
98 StandardCompileOpts("std-compile-opts",
99                    cl::desc("Include the standard compile time optimizations"));
100 
101 static cl::opt<bool>
102 StandardLinkOpts("std-link-opts",
103                  cl::desc("Include the standard link time optimizations"));
104 
105 static cl::opt<bool>
106 OptLevelO1("O1",
107            cl::desc("Optimization level 1. Similar to llvm-gcc -O1"));
108 
109 static cl::opt<bool>
110 OptLevelO2("O2",
111            cl::desc("Optimization level 2. Similar to llvm-gcc -O2"));
112 
113 static cl::opt<bool>
114 OptLevelO3("O3",
115            cl::desc("Optimization level 3. Similar to llvm-gcc -O3"));
116 
117 static cl::opt<bool>
118 UnitAtATime("funit-at-a-time",
119             cl::desc("Enable IPO. This is same as llvm-gcc's -funit-at-a-time"),
120             cl::init(true));
121 
122 static cl::opt<bool>
123 DisableSimplifyLibCalls("disable-simplify-libcalls",
124                         cl::desc("Disable simplify-libcalls"));
125 
126 static cl::opt<bool>
127 Quiet("q", cl::desc("Obsolete option"), cl::Hidden);
128 
129 static cl::alias
130 QuietA("quiet", cl::desc("Alias for -q"), cl::aliasopt(Quiet));
131 
132 static cl::opt<bool>
133 AnalyzeOnly("analyze", cl::desc("Only perform analysis, no optimization"));
134 
135 static cl::opt<bool>
136 PrintBreakpoints("print-breakpoints-for-testing",
137                  cl::desc("Print select breakpoints location for testing"));
138 
139 static cl::opt<std::string>
140 DefaultDataLayout("default-data-layout",
141           cl::desc("data layout string to use if not specified by module"),
142           cl::value_desc("layout-string"), cl::init(""));
143 
144 // ---------- Define Printers for module and function passes ------------
145 namespace {
146 
147 struct CallGraphSCCPassPrinter : public CallGraphSCCPass {
148   static char ID;
149   const PassInfo *PassToPrint;
150   raw_ostream &Out;
151   std::string PassName;
152 
CallGraphSCCPassPrinter__anona0255cf60111::CallGraphSCCPassPrinter153   CallGraphSCCPassPrinter(const PassInfo *PI, raw_ostream &out) :
154     CallGraphSCCPass(ID), PassToPrint(PI), Out(out) {
155       std::string PassToPrintName =  PassToPrint->getPassName();
156       PassName = "CallGraphSCCPass Printer: " + PassToPrintName;
157     }
158 
runOnSCC__anona0255cf60111::CallGraphSCCPassPrinter159   virtual bool runOnSCC(CallGraphSCC &SCC) {
160     if (!Quiet)
161       Out << "Printing analysis '" << PassToPrint->getPassName() << "':\n";
162 
163     // Get and print pass...
164     for (CallGraphSCC::iterator I = SCC.begin(), E = SCC.end(); I != E; ++I) {
165       Function *F = (*I)->getFunction();
166       if (F)
167         getAnalysisID<Pass>(PassToPrint->getTypeInfo()).print(Out,
168                                                               F->getParent());
169     }
170     return false;
171   }
172 
getPassName__anona0255cf60111::CallGraphSCCPassPrinter173   virtual const char *getPassName() const { return PassName.c_str(); }
174 
getAnalysisUsage__anona0255cf60111::CallGraphSCCPassPrinter175   virtual void getAnalysisUsage(AnalysisUsage &AU) const {
176     AU.addRequiredID(PassToPrint->getTypeInfo());
177     AU.setPreservesAll();
178   }
179 };
180 
181 char CallGraphSCCPassPrinter::ID = 0;
182 
183 struct ModulePassPrinter : public ModulePass {
184   static char ID;
185   const PassInfo *PassToPrint;
186   raw_ostream &Out;
187   std::string PassName;
188 
ModulePassPrinter__anona0255cf60111::ModulePassPrinter189   ModulePassPrinter(const PassInfo *PI, raw_ostream &out)
190     : ModulePass(ID), PassToPrint(PI), Out(out) {
191       std::string PassToPrintName =  PassToPrint->getPassName();
192       PassName = "ModulePass Printer: " + PassToPrintName;
193     }
194 
runOnModule__anona0255cf60111::ModulePassPrinter195   virtual bool runOnModule(Module &M) {
196     if (!Quiet)
197       Out << "Printing analysis '" << PassToPrint->getPassName() << "':\n";
198 
199     // Get and print pass...
200     getAnalysisID<Pass>(PassToPrint->getTypeInfo()).print(Out, &M);
201     return false;
202   }
203 
getPassName__anona0255cf60111::ModulePassPrinter204   virtual const char *getPassName() const { return PassName.c_str(); }
205 
getAnalysisUsage__anona0255cf60111::ModulePassPrinter206   virtual void getAnalysisUsage(AnalysisUsage &AU) const {
207     AU.addRequiredID(PassToPrint->getTypeInfo());
208     AU.setPreservesAll();
209   }
210 };
211 
212 char ModulePassPrinter::ID = 0;
213 struct FunctionPassPrinter : public FunctionPass {
214   const PassInfo *PassToPrint;
215   raw_ostream &Out;
216   static char ID;
217   std::string PassName;
218 
FunctionPassPrinter__anona0255cf60111::FunctionPassPrinter219   FunctionPassPrinter(const PassInfo *PI, raw_ostream &out)
220     : FunctionPass(ID), PassToPrint(PI), Out(out) {
221       std::string PassToPrintName =  PassToPrint->getPassName();
222       PassName = "FunctionPass Printer: " + PassToPrintName;
223     }
224 
runOnFunction__anona0255cf60111::FunctionPassPrinter225   virtual bool runOnFunction(Function &F) {
226     if (!Quiet)
227       Out << "Printing analysis '" << PassToPrint->getPassName()
228           << "' for function '" << F.getName() << "':\n";
229 
230     // Get and print pass...
231     getAnalysisID<Pass>(PassToPrint->getTypeInfo()).print(Out,
232             F.getParent());
233     return false;
234   }
235 
getPassName__anona0255cf60111::FunctionPassPrinter236   virtual const char *getPassName() const { return PassName.c_str(); }
237 
getAnalysisUsage__anona0255cf60111::FunctionPassPrinter238   virtual void getAnalysisUsage(AnalysisUsage &AU) const {
239     AU.addRequiredID(PassToPrint->getTypeInfo());
240     AU.setPreservesAll();
241   }
242 };
243 
244 char FunctionPassPrinter::ID = 0;
245 
246 struct LoopPassPrinter : public LoopPass {
247   static char ID;
248   const PassInfo *PassToPrint;
249   raw_ostream &Out;
250   std::string PassName;
251 
LoopPassPrinter__anona0255cf60111::LoopPassPrinter252   LoopPassPrinter(const PassInfo *PI, raw_ostream &out) :
253     LoopPass(ID), PassToPrint(PI), Out(out) {
254       std::string PassToPrintName =  PassToPrint->getPassName();
255       PassName = "LoopPass Printer: " + PassToPrintName;
256     }
257 
258 
runOnLoop__anona0255cf60111::LoopPassPrinter259   virtual bool runOnLoop(Loop *L, LPPassManager &LPM) {
260     if (!Quiet)
261       Out << "Printing analysis '" << PassToPrint->getPassName() << "':\n";
262 
263     // Get and print pass...
264     getAnalysisID<Pass>(PassToPrint->getTypeInfo()).print(Out,
265                         L->getHeader()->getParent()->getParent());
266     return false;
267   }
268 
getPassName__anona0255cf60111::LoopPassPrinter269   virtual const char *getPassName() const { return PassName.c_str(); }
270 
getAnalysisUsage__anona0255cf60111::LoopPassPrinter271   virtual void getAnalysisUsage(AnalysisUsage &AU) const {
272     AU.addRequiredID(PassToPrint->getTypeInfo());
273     AU.setPreservesAll();
274   }
275 };
276 
277 char LoopPassPrinter::ID = 0;
278 
279 struct RegionPassPrinter : public RegionPass {
280   static char ID;
281   const PassInfo *PassToPrint;
282   raw_ostream &Out;
283   std::string PassName;
284 
RegionPassPrinter__anona0255cf60111::RegionPassPrinter285   RegionPassPrinter(const PassInfo *PI, raw_ostream &out) : RegionPass(ID),
286     PassToPrint(PI), Out(out) {
287     std::string PassToPrintName =  PassToPrint->getPassName();
288     PassName = "RegionPass Printer: " + PassToPrintName;
289   }
290 
runOnRegion__anona0255cf60111::RegionPassPrinter291   virtual bool runOnRegion(Region *R, RGPassManager &RGM) {
292     if (!Quiet) {
293       Out << "Printing analysis '" << PassToPrint->getPassName() << "' for "
294         << "region: '" << R->getNameStr() << "' in function '"
295         << R->getEntry()->getParent()->getNameStr() << "':\n";
296     }
297     // Get and print pass...
298    getAnalysisID<Pass>(PassToPrint->getTypeInfo()).print(Out,
299                        R->getEntry()->getParent()->getParent());
300     return false;
301   }
302 
getPassName__anona0255cf60111::RegionPassPrinter303   virtual const char *getPassName() const { return PassName.c_str(); }
304 
getAnalysisUsage__anona0255cf60111::RegionPassPrinter305   virtual void getAnalysisUsage(AnalysisUsage &AU) const {
306     AU.addRequiredID(PassToPrint->getTypeInfo());
307     AU.setPreservesAll();
308   }
309 };
310 
311 char RegionPassPrinter::ID = 0;
312 
313 struct BasicBlockPassPrinter : public BasicBlockPass {
314   const PassInfo *PassToPrint;
315   raw_ostream &Out;
316   static char ID;
317   std::string PassName;
318 
BasicBlockPassPrinter__anona0255cf60111::BasicBlockPassPrinter319   BasicBlockPassPrinter(const PassInfo *PI, raw_ostream &out)
320     : BasicBlockPass(ID), PassToPrint(PI), Out(out) {
321       std::string PassToPrintName =  PassToPrint->getPassName();
322       PassName = "BasicBlockPass Printer: " + PassToPrintName;
323     }
324 
runOnBasicBlock__anona0255cf60111::BasicBlockPassPrinter325   virtual bool runOnBasicBlock(BasicBlock &BB) {
326     if (!Quiet)
327       Out << "Printing Analysis info for BasicBlock '" << BB.getName()
328           << "': Pass " << PassToPrint->getPassName() << ":\n";
329 
330     // Get and print pass...
331     getAnalysisID<Pass>(PassToPrint->getTypeInfo()).print(Out,
332             BB.getParent()->getParent());
333     return false;
334   }
335 
getPassName__anona0255cf60111::BasicBlockPassPrinter336   virtual const char *getPassName() const { return PassName.c_str(); }
337 
getAnalysisUsage__anona0255cf60111::BasicBlockPassPrinter338   virtual void getAnalysisUsage(AnalysisUsage &AU) const {
339     AU.addRequiredID(PassToPrint->getTypeInfo());
340     AU.setPreservesAll();
341   }
342 };
343 
344 char BasicBlockPassPrinter::ID = 0;
345 
346 struct BreakpointPrinter : public ModulePass {
347   raw_ostream &Out;
348   static char ID;
349 
BreakpointPrinter__anona0255cf60111::BreakpointPrinter350   BreakpointPrinter(raw_ostream &out)
351     : ModulePass(ID), Out(out) {
352     }
353 
getContextName__anona0255cf60111::BreakpointPrinter354   void getContextName(DIDescriptor Context, std::string &N) {
355     if (Context.isNameSpace()) {
356       DINameSpace NS(Context);
357       if (!NS.getName().empty()) {
358         getContextName(NS.getContext(), N);
359         N = N + NS.getName().str() + "::";
360       }
361     } else if (Context.isType()) {
362       DIType TY(Context);
363       if (!TY.getName().empty()) {
364         getContextName(TY.getContext(), N);
365         N = N + TY.getName().str() + "::";
366       }
367     }
368   }
369 
runOnModule__anona0255cf60111::BreakpointPrinter370   virtual bool runOnModule(Module &M) {
371     StringSet<> Processed;
372     if (NamedMDNode *NMD = M.getNamedMetadata("llvm.dbg.sp"))
373       for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i) {
374         std::string Name;
375         DISubprogram SP(NMD->getOperand(i));
376         if (SP.Verify())
377           getContextName(SP.getContext(), Name);
378         Name = Name + SP.getDisplayName().str();
379         if (!Name.empty() && Processed.insert(Name)) {
380           Out << Name << "\n";
381         }
382       }
383     return false;
384   }
385 
getAnalysisUsage__anona0255cf60111::BreakpointPrinter386   virtual void getAnalysisUsage(AnalysisUsage &AU) const {
387     AU.setPreservesAll();
388   }
389 };
390 
391 } // anonymous namespace
392 
393 char BreakpointPrinter::ID = 0;
394 
addPass(PassManagerBase & PM,Pass * P)395 static inline void addPass(PassManagerBase &PM, Pass *P) {
396   // Add the pass to the pass manager...
397   PM.add(P);
398 
399   // If we are verifying all of the intermediate steps, add the verifier...
400   if (VerifyEach) PM.add(createVerifierPass());
401 }
402 
403 /// AddOptimizationPasses - This routine adds optimization passes
404 /// based on selected optimization level, OptLevel. This routine
405 /// duplicates llvm-gcc behaviour.
406 ///
407 /// OptLevel - Optimization Level
AddOptimizationPasses(PassManagerBase & MPM,FunctionPassManager & FPM,unsigned OptLevel)408 static void AddOptimizationPasses(PassManagerBase &MPM,FunctionPassManager &FPM,
409                                   unsigned OptLevel) {
410   PassManagerBuilder Builder;
411   Builder.OptLevel = OptLevel;
412 
413   if (DisableInline) {
414     // No inlining pass
415   } else if (OptLevel > 1) {
416     unsigned Threshold = 225;
417     if (OptLevel > 2)
418       Threshold = 275;
419     Builder.Inliner = createFunctionInliningPass(Threshold);
420   } else {
421     Builder.Inliner = createAlwaysInlinerPass();
422   }
423   Builder.DisableUnitAtATime = !UnitAtATime;
424   Builder.DisableUnrollLoops = OptLevel == 0;
425   Builder.DisableSimplifyLibCalls = DisableSimplifyLibCalls;
426 
427   Builder.populateFunctionPassManager(FPM);
428   Builder.populateModulePassManager(MPM);
429 }
430 
AddStandardCompilePasses(PassManagerBase & PM)431 static void AddStandardCompilePasses(PassManagerBase &PM) {
432   PM.add(createVerifierPass());                  // Verify that input is correct
433 
434   // If the -strip-debug command line option was specified, do it.
435   if (StripDebug)
436     addPass(PM, createStripSymbolsPass(true));
437 
438   if (DisableOptimizations) return;
439 
440   // -std-compile-opts adds the same module passes as -O3.
441   PassManagerBuilder Builder;
442   if (!DisableInline)
443     Builder.Inliner = createFunctionInliningPass();
444   Builder.OptLevel = 3;
445   Builder.DisableSimplifyLibCalls = DisableSimplifyLibCalls;
446   Builder.populateModulePassManager(PM);
447 }
448 
AddStandardLinkPasses(PassManagerBase & PM)449 static void AddStandardLinkPasses(PassManagerBase &PM) {
450   PM.add(createVerifierPass());                  // Verify that input is correct
451 
452   // If the -strip-debug command line option was specified, do it.
453   if (StripDebug)
454     addPass(PM, createStripSymbolsPass(true));
455 
456   if (DisableOptimizations) return;
457 
458   PassManagerBuilder Builder;
459   Builder.populateLTOPassManager(PM, /*Internalize=*/ !DisableInternalize,
460                                  /*RunInliner=*/ !DisableInline);
461 }
462 
463 
464 //===----------------------------------------------------------------------===//
465 // main for opt
466 //
main(int argc,char ** argv)467 int main(int argc, char **argv) {
468   sys::PrintStackTraceOnErrorSignal();
469   llvm::PrettyStackTraceProgram X(argc, argv);
470 
471   // Enable debug stream buffering.
472   EnableDebugBuffering = true;
473 
474   llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
475   LLVMContext &Context = getGlobalContext();
476 
477   // Initialize passes
478   PassRegistry &Registry = *PassRegistry::getPassRegistry();
479   initializeCore(Registry);
480   initializeScalarOpts(Registry);
481   initializeIPO(Registry);
482   initializeAnalysis(Registry);
483   initializeIPA(Registry);
484   initializeTransformUtils(Registry);
485   initializeInstCombine(Registry);
486   initializeInstrumentation(Registry);
487   initializeTarget(Registry);
488 
489   cl::ParseCommandLineOptions(argc, argv,
490     "llvm .bc -> .bc modular optimizer and analysis printer\n");
491 
492   if (AnalyzeOnly && NoOutput) {
493     errs() << argv[0] << ": analyze mode conflicts with no-output mode.\n";
494     return 1;
495   }
496 
497   // Allocate a full target machine description only if necessary.
498   // FIXME: The choice of target should be controllable on the command line.
499   std::auto_ptr<TargetMachine> target;
500 
501   SMDiagnostic Err;
502 
503   // Load the input module...
504   std::auto_ptr<Module> M;
505   M.reset(ParseIRFile(InputFilename, Err, Context));
506 
507   if (M.get() == 0) {
508     Err.Print(argv[0], errs());
509     return 1;
510   }
511 
512   // Figure out what stream we are supposed to write to...
513   OwningPtr<tool_output_file> Out;
514   if (NoOutput) {
515     if (!OutputFilename.empty())
516       errs() << "WARNING: The -o (output filename) option is ignored when\n"
517                 "the --disable-output option is used.\n";
518   } else {
519     // Default to standard output.
520     if (OutputFilename.empty())
521       OutputFilename = "-";
522 
523     std::string ErrorInfo;
524     Out.reset(new tool_output_file(OutputFilename.c_str(), ErrorInfo,
525                                    raw_fd_ostream::F_Binary));
526     if (!ErrorInfo.empty()) {
527       errs() << ErrorInfo << '\n';
528       return 1;
529     }
530   }
531 
532   // If the output is set to be emitted to standard out, and standard out is a
533   // console, print out a warning message and refuse to do it.  We don't
534   // impress anyone by spewing tons of binary goo to a terminal.
535   if (!Force && !NoOutput && !AnalyzeOnly && !OutputAssembly)
536     if (CheckBitcodeOutputToConsole(Out->os(), !Quiet))
537       NoOutput = true;
538 
539   // Create a PassManager to hold and optimize the collection of passes we are
540   // about to build.
541   //
542   PassManager Passes;
543 
544   // Add an appropriate TargetLibraryInfo pass for the module's triple.
545   TargetLibraryInfo *TLI = new TargetLibraryInfo(Triple(M->getTargetTriple()));
546 
547   // The -disable-simplify-libcalls flag actually disables all builtin optzns.
548   if (DisableSimplifyLibCalls)
549     TLI->disableAllFunctions();
550   Passes.add(TLI);
551 
552   // Add an appropriate TargetData instance for this module.
553   TargetData *TD = 0;
554   const std::string &ModuleDataLayout = M.get()->getDataLayout();
555   if (!ModuleDataLayout.empty())
556     TD = new TargetData(ModuleDataLayout);
557   else if (!DefaultDataLayout.empty())
558     TD = new TargetData(DefaultDataLayout);
559 
560   if (TD)
561     Passes.add(TD);
562 
563   OwningPtr<FunctionPassManager> FPasses;
564   if (OptLevelO1 || OptLevelO2 || OptLevelO3) {
565     FPasses.reset(new FunctionPassManager(M.get()));
566     if (TD)
567       FPasses->add(new TargetData(*TD));
568   }
569 
570   if (PrintBreakpoints) {
571     // Default to standard output.
572     if (!Out) {
573       if (OutputFilename.empty())
574         OutputFilename = "-";
575 
576       std::string ErrorInfo;
577       Out.reset(new tool_output_file(OutputFilename.c_str(), ErrorInfo,
578                                      raw_fd_ostream::F_Binary));
579       if (!ErrorInfo.empty()) {
580         errs() << ErrorInfo << '\n';
581         return 1;
582       }
583     }
584     Passes.add(new BreakpointPrinter(Out->os()));
585     NoOutput = true;
586   }
587 
588   // If the -strip-debug command line option was specified, add it.  If
589   // -std-compile-opts was also specified, it will handle StripDebug.
590   if (StripDebug && !StandardCompileOpts)
591     addPass(Passes, createStripSymbolsPass(true));
592 
593   // Create a new optimization pass for each one specified on the command line
594   for (unsigned i = 0; i < PassList.size(); ++i) {
595     // Check to see if -std-compile-opts was specified before this option.  If
596     // so, handle it.
597     if (StandardCompileOpts &&
598         StandardCompileOpts.getPosition() < PassList.getPosition(i)) {
599       AddStandardCompilePasses(Passes);
600       StandardCompileOpts = false;
601     }
602 
603     if (StandardLinkOpts &&
604         StandardLinkOpts.getPosition() < PassList.getPosition(i)) {
605       AddStandardLinkPasses(Passes);
606       StandardLinkOpts = false;
607     }
608 
609     if (OptLevelO1 && OptLevelO1.getPosition() < PassList.getPosition(i)) {
610       AddOptimizationPasses(Passes, *FPasses, 1);
611       OptLevelO1 = false;
612     }
613 
614     if (OptLevelO2 && OptLevelO2.getPosition() < PassList.getPosition(i)) {
615       AddOptimizationPasses(Passes, *FPasses, 2);
616       OptLevelO2 = false;
617     }
618 
619     if (OptLevelO3 && OptLevelO3.getPosition() < PassList.getPosition(i)) {
620       AddOptimizationPasses(Passes, *FPasses, 3);
621       OptLevelO3 = false;
622     }
623 
624     const PassInfo *PassInf = PassList[i];
625     Pass *P = 0;
626     if (PassInf->getNormalCtor())
627       P = PassInf->getNormalCtor()();
628     else
629       errs() << argv[0] << ": cannot create pass: "
630              << PassInf->getPassName() << "\n";
631     if (P) {
632       PassKind Kind = P->getPassKind();
633       addPass(Passes, P);
634 
635       if (AnalyzeOnly) {
636         switch (Kind) {
637         case PT_BasicBlock:
638           Passes.add(new BasicBlockPassPrinter(PassInf, Out->os()));
639           break;
640         case PT_Region:
641           Passes.add(new RegionPassPrinter(PassInf, Out->os()));
642           break;
643         case PT_Loop:
644           Passes.add(new LoopPassPrinter(PassInf, Out->os()));
645           break;
646         case PT_Function:
647           Passes.add(new FunctionPassPrinter(PassInf, Out->os()));
648           break;
649         case PT_CallGraphSCC:
650           Passes.add(new CallGraphSCCPassPrinter(PassInf, Out->os()));
651           break;
652         default:
653           Passes.add(new ModulePassPrinter(PassInf, Out->os()));
654           break;
655         }
656       }
657     }
658 
659     if (PrintEachXForm)
660       Passes.add(createPrintModulePass(&errs()));
661   }
662 
663   // If -std-compile-opts was specified at the end of the pass list, add them.
664   if (StandardCompileOpts) {
665     AddStandardCompilePasses(Passes);
666     StandardCompileOpts = false;
667   }
668 
669   if (StandardLinkOpts) {
670     AddStandardLinkPasses(Passes);
671     StandardLinkOpts = false;
672   }
673 
674   if (OptLevelO1)
675     AddOptimizationPasses(Passes, *FPasses, 1);
676 
677   if (OptLevelO2)
678     AddOptimizationPasses(Passes, *FPasses, 2);
679 
680   if (OptLevelO3)
681     AddOptimizationPasses(Passes, *FPasses, 3);
682 
683   if (OptLevelO1 || OptLevelO2 || OptLevelO3) {
684     FPasses->doInitialization();
685     for (Module::iterator F = M->begin(), E = M->end(); F != E; ++F)
686       FPasses->run(*F);
687     FPasses->doFinalization();
688   }
689 
690   // Check that the module is well formed on completion of optimization
691   if (!NoVerify && !VerifyEach)
692     Passes.add(createVerifierPass());
693 
694   // Write bitcode or assembly to the output as the last step...
695   if (!NoOutput && !AnalyzeOnly) {
696     if (OutputAssembly)
697       Passes.add(createPrintModulePass(&Out->os()));
698     else
699       Passes.add(createBitcodeWriterPass(Out->os()));
700   }
701 
702   // Before executing passes, print the final values of the LLVM options.
703   cl::PrintOptionValues();
704 
705   // Now that we have all of the passes ready, run them.
706   Passes.run(*M.get());
707 
708   // Declare success.
709   if (!NoOutput || PrintBreakpoints)
710     Out->keep();
711 
712   return 0;
713 }
714