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/IR/LLVMContext.h"
19 #include "llvm/IR/LegacyPassManager.h"
20 #include "llvm/IR/LegacyPassNameParser.h"
21 #include "llvm/LinkAllIR.h"
22 #include "llvm/LinkAllPasses.h"
23 #include "llvm/Support/CommandLine.h"
24 #include "llvm/Support/ManagedStatic.h"
25 #include "llvm/Support/PluginLoader.h"
26 #include "llvm/Support/PrettyStackTrace.h"
27 #include "llvm/Support/Process.h"
28 #include "llvm/Support/Signals.h"
29 #include "llvm/Support/Valgrind.h"
30 #include "llvm/Transforms/IPO/PassManagerBuilder.h"
31 
32 //Enable this macro to debug bugpoint itself.
33 //#define DEBUG_BUGPOINT 1
34 
35 using namespace llvm;
36 
37 static cl::opt<bool>
38 FindBugs("find-bugs", cl::desc("Run many different optimization sequences "
39                                "on program to find bugs"), cl::init(false));
40 
41 static cl::list<std::string>
42 InputFilenames(cl::Positional, cl::OneOrMore,
43                cl::desc("<input llvm ll/bc files>"));
44 
45 static cl::opt<unsigned>
46 TimeoutValue("timeout", cl::init(300), cl::value_desc("seconds"),
47              cl::desc("Number of seconds program is allowed to run before it "
48                       "is killed (default is 300s), 0 disables timeout"));
49 
50 static cl::opt<int>
51 MemoryLimit("mlimit", cl::init(-1), cl::value_desc("MBytes"),
52             cl::desc("Maximum amount of memory to use. 0 disables check."
53                      " Defaults to 400MB (800MB under valgrind)."));
54 
55 static cl::opt<bool>
56 UseValgrind("enable-valgrind",
57             cl::desc("Run optimizations through valgrind"));
58 
59 // The AnalysesList is automatically populated with registered Passes by the
60 // PassNameParser.
61 //
62 static cl::list<const PassInfo*, bool, PassNameParser>
63 PassList(cl::desc("Passes available:"), cl::ZeroOrMore);
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<bool>
70 OptLevelO1("O1",
71            cl::desc("Optimization level 1. Identical to 'opt -O1'"));
72 
73 static cl::opt<bool>
74 OptLevelO2("O2",
75            cl::desc("Optimization level 2. Identical to 'opt -O2'"));
76 
77 static cl::opt<bool>
78 OptLevelO3("O3",
79            cl::desc("Optimization level 3. Identical to 'opt -O3'"));
80 
81 static cl::opt<std::string>
82 OverrideTriple("mtriple", cl::desc("Override target triple for module"));
83 
84 /// BugpointIsInterrupted - Set to true when the user presses ctrl-c.
85 bool llvm::BugpointIsInterrupted = false;
86 
87 #ifndef DEBUG_BUGPOINT
BugpointInterruptFunction()88 static void BugpointInterruptFunction() {
89   BugpointIsInterrupted = true;
90 }
91 #endif
92 
93 // Hack to capture a pass list.
94 namespace {
95   class AddToDriver : public legacy::FunctionPassManager {
96     BugDriver &D;
97   public:
AddToDriver(BugDriver & _D)98     AddToDriver(BugDriver &_D) : FunctionPassManager(nullptr), D(_D) {}
99 
add(Pass * P)100     void add(Pass *P) override {
101       const void *ID = P->getPassID();
102       const PassInfo *PI = PassRegistry::getPassRegistry()->getPassInfo(ID);
103       D.addPass(PI->getPassArgument());
104     }
105   };
106 }
107 
108 #ifdef LINK_POLLY_INTO_TOOLS
109 namespace polly {
110 void initializePollyPasses(llvm::PassRegistry &Registry);
111 }
112 #endif
113 
main(int argc,char ** argv)114 int main(int argc, char **argv) {
115 #ifndef DEBUG_BUGPOINT
116   llvm::sys::PrintStackTraceOnErrorSignal();
117   llvm::PrettyStackTraceProgram X(argc, argv);
118   llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
119 #endif
120 
121   // Initialize passes
122   PassRegistry &Registry = *PassRegistry::getPassRegistry();
123   initializeCore(Registry);
124   initializeScalarOpts(Registry);
125   initializeObjCARCOpts(Registry);
126   initializeVectorization(Registry);
127   initializeIPO(Registry);
128   initializeAnalysis(Registry);
129   initializeTransformUtils(Registry);
130   initializeInstCombine(Registry);
131   initializeInstrumentation(Registry);
132   initializeTarget(Registry);
133 
134 #ifdef LINK_POLLY_INTO_TOOLS
135   polly::initializePollyPasses(Registry);
136 #endif
137 
138   cl::ParseCommandLineOptions(argc, argv,
139                               "LLVM automatic testcase reducer. See\nhttp://"
140                               "llvm.org/cmds/bugpoint.html"
141                               " for more information.\n");
142 #ifndef DEBUG_BUGPOINT
143   sys::SetInterruptFunction(BugpointInterruptFunction);
144 #endif
145 
146   LLVMContext& Context = getGlobalContext();
147   // If we have an override, set it and then track the triple we want Modules
148   // to use.
149   if (!OverrideTriple.empty()) {
150     TargetTriple.setTriple(Triple::normalize(OverrideTriple));
151     outs() << "Override triple set to '" << TargetTriple.getTriple() << "'\n";
152   }
153 
154   if (MemoryLimit < 0) {
155     // Set the default MemoryLimit.  Be sure to update the flag's description if
156     // you change this.
157     if (sys::RunningOnValgrind() || UseValgrind)
158       MemoryLimit = 800;
159     else
160       MemoryLimit = 400;
161   }
162 
163   BugDriver D(argv[0], FindBugs, TimeoutValue, MemoryLimit,
164               UseValgrind, Context);
165   if (D.addSources(InputFilenames)) return 1;
166 
167   AddToDriver PM(D);
168 
169   if (StandardLinkOpts) {
170     PassManagerBuilder Builder;
171     Builder.Inliner = createFunctionInliningPass();
172     Builder.populateLTOPassManager(PM);
173   }
174 
175   if (OptLevelO1 || OptLevelO2 || OptLevelO3) {
176     PassManagerBuilder Builder;
177     if (OptLevelO1)
178       Builder.Inliner = createAlwaysInlinerPass();
179     else if (OptLevelO2)
180       Builder.Inliner = createFunctionInliningPass(225);
181     else
182       Builder.Inliner = createFunctionInliningPass(275);
183     Builder.populateFunctionPassManager(PM);
184     Builder.populateModulePassManager(PM);
185   }
186 
187   for (const PassInfo *PI : PassList)
188     D.addPass(PI->getPassArgument());
189 
190   // Bugpoint has the ability of generating a plethora of core files, so to
191   // avoid filling up the disk, we prevent it
192 #ifndef DEBUG_BUGPOINT
193   sys::Process::PreventCoreFiles();
194 #endif
195 
196   std::string Error;
197   bool Failure = D.run(Error);
198   if (!Error.empty()) {
199     errs() << Error;
200     return 1;
201   }
202   return Failure;
203 }
204