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/System/Process.h"
27 #include "llvm/System/Signals.h"
28 #include "llvm/LinkAllVMCore.h"
29 using namespace llvm;
30 
31 // AsChild - Specifies that this invocation of bugpoint is being generated
32 // from a parent process. It is not intended to be used by users so the
33 // option is hidden.
34 static cl::opt<bool>
35 AsChild("as-child", cl::desc("Run bugpoint as child process"),
36         cl::ReallyHidden);
37 
38 static cl::opt<bool>
39 FindBugs("find-bugs", cl::desc("Run many different optimization sequences "
40                                "on program to find bugs"), cl::init(false));
41 
42 static cl::list<std::string>
43 InputFilenames(cl::Positional, cl::OneOrMore,
44                cl::desc("<input llvm ll/bc files>"));
45 
46 static cl::opt<unsigned>
47 TimeoutValue("timeout", cl::init(300), cl::value_desc("seconds"),
48              cl::desc("Number of seconds program is allowed to run before it "
49                       "is killed (default is 300s), 0 disables timeout"));
50 
51 static cl::opt<unsigned>
52 MemoryLimit("mlimit", cl::init(100), cl::value_desc("MBytes"),
53              cl::desc("Maximum amount of memory to use. 0 disables check."));
54 
55 // The AnalysesList is automatically populated with registered Passes by the
56 // PassNameParser.
57 //
58 static cl::list<const PassInfo*, bool, PassNameParser>
59 PassList(cl::desc("Passes available:"), cl::ZeroOrMore);
60 
61 static cl::opt<bool>
62 StandardCompileOpts("std-compile-opts",
63                    cl::desc("Include the standard compile time optimizations"));
64 
65 static cl::opt<bool>
66 StandardLinkOpts("std-link-opts",
67                  cl::desc("Include the standard link time optimizations"));
68 
69 static cl::opt<std::string>
70 OverrideTriple("mtriple", cl::desc("Override target triple for module"));
71 
72 /// BugpointIsInterrupted - Set to true when the user presses ctrl-c.
73 bool llvm::BugpointIsInterrupted = false;
74 
75 static void BugpointInterruptFunction() {
76   BugpointIsInterrupted = true;
77 }
78 
79 // Hack to capture a pass list.
80 namespace {
81   class AddToDriver : public PassManager {
82     BugDriver &D;
83   public:
84     AddToDriver(BugDriver &_D) : D(_D) {}
85 
86     virtual void add(Pass *P) {
87       const PassInfo *PI = P->getPassInfo();
88       D.addPasses(&PI, &PI + 1);
89     }
90   };
91 }
92 
93 int main(int argc, char **argv) {
94   llvm::sys::PrintStackTraceOnErrorSignal();
95   llvm::PrettyStackTraceProgram X(argc, argv);
96   llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
97   cl::ParseCommandLineOptions(argc, argv,
98                               "LLVM automatic testcase reducer. See\nhttp://"
99                               "llvm.org/cmds/bugpoint.html"
100                               " for more information.\n");
101   sys::SetInterruptFunction(BugpointInterruptFunction);
102 
103   LLVMContext& Context = getGlobalContext();
104   // If we have an override, set it and then track the triple we want Modules
105   // to use.
106   if (!OverrideTriple.empty()) {
107     TargetTriple.setTriple(OverrideTriple);
108     outs() << "Override triple set to '" << OverrideTriple << "'\n";
109   }
110 
111   BugDriver D(argv[0], AsChild, FindBugs, TimeoutValue, MemoryLimit, Context);
112   if (D.addSources(InputFilenames)) return 1;
113 
114   AddToDriver PM(D);
115   if (StandardCompileOpts) {
116     createStandardModulePasses(&PM, 3,
117                                /*OptimizeSize=*/ false,
118                                /*UnitAtATime=*/ true,
119                                /*UnrollLoops=*/ true,
120                                /*SimplifyLibCalls=*/ true,
121                                /*HaveExceptions=*/ true,
122                                createFunctionInliningPass());
123   }
124 
125   if (StandardLinkOpts)
126     createStandardLTOPasses(&PM, /*Internalize=*/true,
127                             /*RunInliner=*/true,
128                             /*VerifyEach=*/false);
129 
130   D.addPasses(PassList.begin(), PassList.end());
131 
132   // Bugpoint has the ability of generating a plethora of core files, so to
133   // avoid filling up the disk, we prevent it
134   sys::Process::PreventCoreFiles();
135 
136   try {
137     return D.run();
138   } catch (ToolExecutionError &TEE) {
139     errs() << "Tool execution error: " << TEE.what() << '\n';
140   } catch (const std::string& msg) {
141     errs() << argv[0] << ": " << msg << "\n";
142   } catch (const std::bad_alloc&) {
143     errs() << "Oh no, a bugpoint process ran out of memory!\n"
144               "To increase the allocation limits for bugpoint child\n"
145               "processes, use the -mlimit option.\n";
146   } catch (const std::exception &e) {
147     errs() << "Whoops, a std::exception leaked out of bugpoint: "
148            << e.what() << "\n"
149            << "This is a bug in bugpoint!\n";
150   } catch (...) {
151     errs() << "Whoops, an exception leaked out of bugpoint.  "
152            << "This is a bug in bugpoint!\n";
153   }
154   return 1;
155 }
156