1 //===- bugpoint.cpp - The LLVM Bugpoint utility ---------------------------===//
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 program is an automated compiler debugger tool.  It is used to narrow
11 // down miscompilations and crash problems to a specific pass in the compiler,
12 // and the specific Module or Function input that is causing the problem.
13 //
14 //===----------------------------------------------------------------------===//
15 
16 #include "BugDriver.h"
17 #include "ToolRunner.h"
18 #include "llvm/LinkAllPasses.h"
19 #include "llvm/LLVMContext.h"
20 #include "llvm/Support/PassNameParser.h"
21 #include "llvm/Support/CommandLine.h"
22 #include "llvm/Support/ManagedStatic.h"
23 #include "llvm/Support/PluginLoader.h"
24 #include "llvm/Support/PrettyStackTrace.h"
25 #include "llvm/Support/StandardPasses.h"
26 #include "llvm/Support/Process.h"
27 #include "llvm/Support/Signals.h"
28 #include "llvm/Support/Valgrind.h"
29 #include "llvm/LinkAllVMCore.h"
30 
31 //Enable this macro to debug bugpoint itself.
32 //#define DEBUG_BUGPOINT 1
33 
34 using namespace llvm;
35 
36 static cl::opt<bool>
37 FindBugs("find-bugs", cl::desc("Run many different optimization sequences "
38                                "on program to find bugs"), cl::init(false));
39 
40 static cl::list<std::string>
41 InputFilenames(cl::Positional, cl::OneOrMore,
42                cl::desc("<input llvm ll/bc files>"));
43 
44 static cl::opt<unsigned>
45 TimeoutValue("timeout", cl::init(300), cl::value_desc("seconds"),
46              cl::desc("Number of seconds program is allowed to run before it "
47                       "is killed (default is 300s), 0 disables timeout"));
48 
49 static cl::opt<int>
50 MemoryLimit("mlimit", cl::init(-1), cl::value_desc("MBytes"),
51              cl::desc("Maximum amount of memory to use. 0 disables check."
52                       " Defaults to 100MB (800MB under valgrind)."));
53 
54 static cl::opt<bool>
55 UseValgrind("enable-valgrind",
56             cl::desc("Run optimizations through valgrind"));
57 
58 // The AnalysesList is automatically populated with registered Passes by the
59 // PassNameParser.
60 //
61 static cl::list<const PassInfo*, bool, PassNameParser>
62 PassList(cl::desc("Passes available:"), cl::ZeroOrMore);
63 
64 static cl::opt<bool>
65 StandardCompileOpts("std-compile-opts",
66                    cl::desc("Include the standard compile time optimizations"));
67 
68 static cl::opt<bool>
69 StandardLinkOpts("std-link-opts",
70                  cl::desc("Include the standard link time optimizations"));
71 
72 static cl::opt<std::string>
73 OverrideTriple("mtriple", cl::desc("Override target triple for module"));
74 
75 /// BugpointIsInterrupted - Set to true when the user presses ctrl-c.
76 bool llvm::BugpointIsInterrupted = false;
77 
78 #ifndef DEBUG_BUGPOINT
79 static void BugpointInterruptFunction() {
80   BugpointIsInterrupted = true;
81 }
82 #endif
83 
84 // Hack to capture a pass list.
85 namespace {
86   class AddToDriver : public PassManager {
87     BugDriver &D;
88   public:
89     AddToDriver(BugDriver &_D) : D(_D) {}
90 
91     virtual void add(Pass *P) {
92       const void *ID = P->getPassID();
93       const PassInfo *PI = PassRegistry::getPassRegistry()->getPassInfo(ID);
94       D.addPass(PI->getPassArgument());
95     }
96   };
97 }
98 
99 int main(int argc, char **argv) {
100 #ifndef DEBUG_BUGPOINT
101   llvm::sys::PrintStackTraceOnErrorSignal();
102   llvm::PrettyStackTraceProgram X(argc, argv);
103   llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
104 #endif
105 
106   // Initialize passes
107   PassRegistry &Registry = *PassRegistry::getPassRegistry();
108   initializeCore(Registry);
109   initializeScalarOpts(Registry);
110   initializeIPO(Registry);
111   initializeAnalysis(Registry);
112   initializeIPA(Registry);
113   initializeTransformUtils(Registry);
114   initializeInstCombine(Registry);
115   initializeInstrumentation(Registry);
116   initializeTarget(Registry);
117 
118   cl::ParseCommandLineOptions(argc, argv,
119                               "LLVM automatic testcase reducer. See\nhttp://"
120                               "llvm.org/cmds/bugpoint.html"
121                               " for more information.\n");
122 #ifndef DEBUG_BUGPOINT
123   sys::SetInterruptFunction(BugpointInterruptFunction);
124 #endif
125 
126   LLVMContext& Context = getGlobalContext();
127   // If we have an override, set it and then track the triple we want Modules
128   // to use.
129   if (!OverrideTriple.empty()) {
130     TargetTriple.setTriple(Triple::normalize(OverrideTriple));
131     outs() << "Override triple set to '" << TargetTriple.getTriple() << "'\n";
132   }
133 
134   if (MemoryLimit < 0) {
135     // Set the default MemoryLimit.  Be sure to update the flag's description if
136     // you change this.
137     if (sys::RunningOnValgrind() || UseValgrind)
138       MemoryLimit = 800;
139     else
140       MemoryLimit = 100;
141   }
142 
143   BugDriver D(argv[0], FindBugs, TimeoutValue, MemoryLimit,
144               UseValgrind, Context);
145   if (D.addSources(InputFilenames)) return 1;
146 
147   AddToDriver PM(D);
148   if (StandardCompileOpts) {
149     createStandardModulePasses(&PM, 3,
150                                /*OptimizeSize=*/ false,
151                                /*UnitAtATime=*/ true,
152                                /*UnrollLoops=*/ true,
153                                /*SimplifyLibCalls=*/ true,
154                                /*HaveExceptions=*/ true,
155                                createFunctionInliningPass());
156   }
157 
158   if (StandardLinkOpts)
159     createStandardLTOPasses(&PM, /*Internalize=*/true,
160                             /*RunInliner=*/true,
161                             /*VerifyEach=*/false);
162 
163 
164   for (std::vector<const PassInfo*>::iterator I = PassList.begin(),
165          E = PassList.end();
166        I != E; ++I) {
167     const PassInfo* PI = *I;
168     D.addPass(PI->getPassArgument());
169   }
170 
171   // Bugpoint has the ability of generating a plethora of core files, so to
172   // avoid filling up the disk, we prevent it
173 #ifndef DEBUG_BUGPOINT
174   sys::Process::PreventCoreFiles();
175 #endif
176 
177   std::string Error;
178   bool Failure = D.run(Error);
179   if (!Error.empty()) {
180     errs() << Error;
181     return 1;
182   }
183   return Failure;
184 }
185