1 //===- bugpoint.cpp - The LLVM Bugpoint utility ---------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This program is an automated compiler debugger tool.  It is used to narrow
10 // down miscompilations and crash problems to a specific pass in the compiler,
11 // and the specific Module or Function input that is causing the problem.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "BugDriver.h"
16 #include "ToolRunner.h"
17 #include "llvm/Config/llvm-config.h"
18 #include "llvm/IR/LLVMContext.h"
19 #include "llvm/IR/LegacyPassManager.h"
20 #include "llvm/IR/LegacyPassNameParser.h"
21 #include "llvm/InitializePasses.h"
22 #include "llvm/LinkAllIR.h"
23 #include "llvm/LinkAllPasses.h"
24 #include "llvm/Passes/PassPlugin.h"
25 #include "llvm/Support/CommandLine.h"
26 #include "llvm/Support/InitLLVM.h"
27 #include "llvm/Support/PluginLoader.h"
28 #include "llvm/Support/PrettyStackTrace.h"
29 #include "llvm/Support/Process.h"
30 #include "llvm/Support/TargetSelect.h"
31 #include "llvm/Support/Valgrind.h"
32 #include "llvm/Transforms/IPO/AlwaysInliner.h"
33 
34 // Enable this macro to debug bugpoint itself.
35 //#define DEBUG_BUGPOINT 1
36 
37 using namespace llvm;
38 
39 static cl::opt<bool>
40     FindBugs("find-bugs", cl::desc("Run many different optimization sequences "
41                                    "on program to find bugs"),
42              cl::init(false));
43 
44 static cl::list<std::string>
45     InputFilenames(cl::Positional, cl::OneOrMore,
46                    cl::desc("<input llvm ll/bc files>"));
47 
48 static cl::opt<unsigned> TimeoutValue(
49     "timeout", cl::init(300), cl::value_desc("seconds"),
50     cl::desc("Number of seconds program is allowed to run before it "
51              "is killed (default is 300s), 0 disables timeout"));
52 
53 static cl::opt<int> MemoryLimit(
54     "mlimit", cl::init(-1), cl::value_desc("MBytes"),
55     cl::desc("Maximum amount of memory to use. 0 disables check. Defaults to "
56              "400MB (800MB under valgrind, 0 with sanitizers)."));
57 
58 static cl::opt<bool>
59     UseValgrind("enable-valgrind",
60                 cl::desc("Run optimizations through valgrind"));
61 
62 // The AnalysesList is automatically populated with registered Passes by the
63 // PassNameParser.
64 //
65 static cl::list<const PassInfo *, bool, PassNameParser>
66     PassList(cl::desc("Passes available:"));
67 
68 static cl::opt<std::string>
69     OverrideTriple("mtriple", cl::desc("Override target triple for module"));
70 
71 /// BugpointIsInterrupted - Set to true when the user presses ctrl-c.
72 bool llvm::BugpointIsInterrupted = false;
73 
74 #ifndef DEBUG_BUGPOINT
75 static void BugpointInterruptFunction() { BugpointIsInterrupted = true; }
76 #endif
77 
78 // Hack to capture a pass list.
79 namespace {
80 class AddToDriver : public legacy::FunctionPassManager {
81   BugDriver &D;
82 
83 public:
84   AddToDriver(BugDriver &_D) : FunctionPassManager(nullptr), D(_D) {}
85 
86   void add(Pass *P) override {
87     const void *ID = P->getPassID();
88     const PassInfo *PI = PassRegistry::getPassRegistry()->getPassInfo(ID);
89     D.addPass(std::string(PI->getPassArgument()));
90   }
91 };
92 }
93 
94 #define HANDLE_EXTENSION(Ext)                                                  \
95   llvm::PassPluginLibraryInfo get##Ext##PluginInfo();
96 #include "llvm/Support/Extension.def"
97 
98 int main(int argc, char **argv) {
99 #ifndef DEBUG_BUGPOINT
100   InitLLVM X(argc, argv);
101 #endif
102 
103   // Initialize passes
104   PassRegistry &Registry = *PassRegistry::getPassRegistry();
105   initializeCore(Registry);
106   initializeScalarOpts(Registry);
107   initializeVectorization(Registry);
108   initializeIPO(Registry);
109   initializeAnalysis(Registry);
110   initializeTransformUtils(Registry);
111   initializeInstCombine(Registry);
112   initializeTarget(Registry);
113 
114   if (std::getenv("bar") == (char*) -1) {
115     InitializeAllTargets();
116     InitializeAllTargetMCs();
117     InitializeAllAsmPrinters();
118     InitializeAllAsmParsers();
119   }
120 
121   cl::ParseCommandLineOptions(argc, argv,
122                               "LLVM automatic testcase reducer. See\nhttp://"
123                               "llvm.org/cmds/bugpoint.html"
124                               " for more information.\n");
125 #ifndef DEBUG_BUGPOINT
126   sys::SetInterruptFunction(BugpointInterruptFunction);
127 #endif
128 
129   LLVMContext Context;
130   // If we have an override, set it and then track the triple we want Modules
131   // to use.
132   if (!OverrideTriple.empty()) {
133     TargetTriple.setTriple(Triple::normalize(OverrideTriple));
134     outs() << "Override triple set to '" << TargetTriple.getTriple() << "'\n";
135   }
136 
137   if (MemoryLimit < 0) {
138     // Set the default MemoryLimit.  Be sure to update the flag's description if
139     // you change this.
140     if (sys::RunningOnValgrind() || UseValgrind)
141       MemoryLimit = 800;
142     else
143       MemoryLimit = 400;
144 #if (LLVM_ADDRESS_SANITIZER_BUILD || LLVM_MEMORY_SANITIZER_BUILD ||            \
145      LLVM_THREAD_SANITIZER_BUILD)
146     // Starting from kernel 4.9 memory allocated with mmap is counted against
147     // RLIMIT_DATA. Sanitizers need to allocate tens of terabytes for shadow.
148     MemoryLimit = 0;
149 #endif
150   }
151 
152   BugDriver D(argv[0], FindBugs, TimeoutValue, MemoryLimit, UseValgrind,
153               Context);
154   if (D.addSources(InputFilenames))
155     return 1;
156 
157   AddToDriver PM(D);
158 
159   for (const PassInfo *PI : PassList)
160     D.addPass(std::string(PI->getPassArgument()));
161 
162 // Bugpoint has the ability of generating a plethora of core files, so to
163 // avoid filling up the disk, we prevent it
164 #ifndef DEBUG_BUGPOINT
165   sys::Process::PreventCoreFiles();
166 #endif
167 
168 // Needed to pull in symbols from statically linked extensions, including static
169 // registration. It is unused otherwise because bugpoint has no support for
170 // NewPM.
171 #define HANDLE_EXTENSION(Ext)                                                  \
172   (void)get##Ext##PluginInfo();
173 #include "llvm/Support/Extension.def"
174 
175   if (Error E = D.run()) {
176     errs() << toString(std::move(E));
177     return 1;
178   }
179   return 0;
180 }
181