1//===- BugDriver.h - Top-Level BugPoint class -------------------*- C++ -*-===//
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 class contains all of the shared state and information that is used by
10// the BugPoint tool to track down errors in optimizations. This class is the
11// main driver class that invokes all sub-functionality.
12//
13//===----------------------------------------------------------------------===//
14
15#ifndef LLVM_TOOLS_BUGPOINT_BUGDRIVER_H
16#define LLVM_TOOLS_BUGPOINT_BUGDRIVER_H
17
18#include "llvm/IR/ValueMap.h"
19#include "llvm/Support/CommandLine.h"
20#include "llvm/Support/Error.h"
21#include "llvm/Support/FileSystem.h"
22#include "llvm/Transforms/Utils/ValueMapper.h"
23#include <memory>
24#include <string>
25#include <vector>
26
27namespace llvm {
28
29class Module;
30class GlobalVariable;
31class Function;
32class BasicBlock;
33class AbstractInterpreter;
34class Instruction;
35class LLVMContext;
36
37class CC;
38
39extern bool DisableSimplifyCFG;
40
41/// BugpointIsInterrupted - Set to true when the user presses ctrl-c.
42///
43extern bool BugpointIsInterrupted;
44
45/// Command line options used across files.
46extern cl::list<std::string> InputArgv;
47extern cl::opt<std::string> OutputPrefix;
48
49class BugDriver {
50 LLVMContext &Context;
51 const char *ToolName; // argv[0] of bugpoint
52 std::string ReferenceOutputFile; // Name of `good' output file
53 std::unique_ptr<Module> Program; // The raw program, linked together
54 std::vector<std::string> PassesToRun;
55 AbstractInterpreter *Interpreter; // How to run the program
56 AbstractInterpreter *SafeInterpreter; // To generate reference output, etc.
57 CC *cc;
58 bool run_find_bugs;
59 unsigned Timeout;
60 unsigned MemoryLimit;
61 bool UseValgrind;
62
63 // FIXME: sort out public/private distinctions...
64 friend class ReducePassList;
65
66public:
67 BugDriver(const char *toolname, bool find_bugs, unsigned timeout,
68 unsigned memlimit, bool use_valgrind, LLVMContext &ctxt);
69 ~BugDriver();
70
71 const char *getToolName() const { return ToolName; }
72
73 LLVMContext &getContext() const { return Context; }
74
75 // Set up methods... these methods are used to copy information about the
76 // command line arguments into instance variables of BugDriver.
77 //
78 bool addSources(const std::vector<std::string> &FileNames);
79 void addPass(std::string p) { PassesToRun.push_back(x: std::move(p)); }
80 void setPassesToRun(const std::vector<std::string> &PTR) {
81 PassesToRun = PTR;
82 }
83 ArrayRef<std::string> getPassesToRun() const { return PassesToRun; }
84
85 /// run - The top level method that is invoked after all of the instance
86 /// variables are set up from command line arguments. The \p as_child argument
87 /// indicates whether the driver is to run in parent mode or child mode.
88 ///
89 Error run();
90
91 /// debugOptimizerCrash - This method is called when some optimizer pass
92 /// crashes on input. It attempts to prune down the testcase to something
93 /// reasonable, and figure out exactly which pass is crashing.
94 ///
95 Error debugOptimizerCrash(const std::string &ID = "passes");
96
97 /// debugCodeGeneratorCrash - This method is called when the code generator
98 /// crashes on an input. It attempts to reduce the input as much as possible
99 /// while still causing the code generator to crash.
100 Error debugCodeGeneratorCrash();
101
102 /// debugMiscompilation - This method is used when the passes selected are not
103 /// crashing, but the generated output is semantically different from the
104 /// input.
105 Error debugMiscompilation();
106
107 /// compileSharedObject - This method creates a SharedObject from a given
108 /// BitcodeFile for debugging a code generator.
109 ///
110 Expected<std::string> compileSharedObject(const std::string &BitcodeFile);
111
112 /// debugCodeGenerator - This method narrows down a module to a function or
113 /// set of functions, using the CBE as a ``safe'' code generator for other
114 /// functions that are not under consideration.
115 Error debugCodeGenerator();
116
117 /// isExecutingJIT - Returns true if bugpoint is currently testing the JIT
118 bool isExecutingJIT();
119
120 Module &getProgram() const { return *Program; }
121
122 /// Set the current module to the specified module, returning the old one.
123 std::unique_ptr<Module> swapProgramIn(std::unique_ptr<Module> M);
124
125 AbstractInterpreter *switchToSafeInterpreter() {
126 AbstractInterpreter *Old = Interpreter;
127 Interpreter = (AbstractInterpreter *)SafeInterpreter;
128 return Old;
129 }
130
131 void switchToInterpreter(AbstractInterpreter *AI) { Interpreter = AI; }
132
133 /// If we reduce or update the program somehow, call this method to update
134 /// bugdriver with it. This deletes the old module and sets the specified one
135 /// as the current program.
136 void setNewProgram(std::unique_ptr<Module> M);
137
138 /// Try to compile the specified module. This is used for code generation
139 /// crash testing.
140 Error compileProgram(Module &M) const;
141
142 /// This method runs "Program", capturing the output of the program to a file.
143 /// A recommended filename may be optionally specified.
144 Expected<std::string> executeProgram(const Module &Program,
145 std::string OutputFilename,
146 std::string Bitcode,
147 const std::string &SharedObjects,
148 AbstractInterpreter *AI) const;
149
150 /// Used to create reference output with the "safe" backend, if reference
151 /// output is not provided. If there is a problem with the code generator
152 /// (e.g., llc crashes), this will return false and set Error.
153 Expected<std::string>
154 executeProgramSafely(const Module &Program,
155 const std::string &OutputFile) const;
156
157 /// Calls compileProgram and then records the output into ReferenceOutputFile.
158 /// Returns true if reference file created, false otherwise. Note:
159 /// initializeExecutionEnvironment should be called BEFORE this function.
160 Error createReferenceFile(Module &M, const std::string &Filename =
161 "bugpoint.reference.out-%%%%%%%");
162
163 /// This method executes the specified module and diffs the output against the
164 /// file specified by ReferenceOutputFile. If the output is different, 1 is
165 /// returned. If there is a problem with the code generator (e.g., llc
166 /// crashes), this will return -1 and set Error.
167 Expected<bool> diffProgram(const Module &Program,
168 const std::string &BitcodeFile = "",
169 const std::string &SharedObj = "",
170 bool RemoveBitcode = false) const;
171
172 /// This function is used to output M to a file named "bugpoint-ID.bc".
173 void emitProgressBitcode(const Module &M, const std::string &ID,
174 bool NoFlyer = false) const;
175
176 /// This method clones the current Program and deletes the specified
177 /// instruction from the cloned module. It then runs a series of cleanup
178 /// passes (ADCE and SimplifyCFG) to eliminate any code which depends on the
179 /// value. The modified module is then returned.
180 ///
181 std::unique_ptr<Module> deleteInstructionFromProgram(const Instruction *I,
182 unsigned Simp);
183
184 /// This method clones the current Program and performs a series of cleanups
185 /// intended to get rid of extra cruft on the module. If the
186 /// MayModifySemantics argument is true, then the cleanups is allowed to
187 /// modify how the code behaves.
188 ///
189 std::unique_ptr<Module> performFinalCleanups(std::unique_ptr<Module> M,
190 bool MayModifySemantics = false);
191
192 /// Given a module, extract up to one loop from it into a new function. This
193 /// returns null if there are no extractable loops in the program or if the
194 /// loop extractor crashes.
195 std::unique_ptr<Module> extractLoop(Module *M);
196
197 /// Extract all but the specified basic blocks into their own functions. The
198 /// only detail is that M is actually a module cloned from the one the BBs are
199 /// in, so some mapping needs to be performed. If this operation fails for
200 /// some reason (ie the implementation is buggy), this function should return
201 /// null, otherwise it returns a new Module.
202 std::unique_ptr<Module>
203 extractMappedBlocksFromModule(const std::vector<BasicBlock *> &BBs,
204 Module *M);
205
206 /// Carefully run the specified set of pass on the specified/ module,
207 /// returning the transformed module on success, or a null pointer on failure.
208 std::unique_ptr<Module> runPassesOn(Module *M,
209 const std::vector<std::string> &Passes,
210 ArrayRef<std::string> ExtraArgs = {});
211
212 /// runPasses - Run the specified passes on Program, outputting a bitcode
213 /// file and writting the filename into OutputFile if successful. If the
214 /// optimizations fail for some reason (optimizer crashes), return true,
215 /// otherwise return false. If DeleteOutput is set to true, the bitcode is
216 /// deleted on success, and the filename string is undefined. This prints to
217 /// outs() a single line message indicating whether compilation was successful
218 /// or failed, unless Quiet is set. ExtraArgs specifies additional arguments
219 /// to pass to the child bugpoint instance.
220 bool runPasses(Module &Program, const std::vector<std::string> &PassesToRun,
221 std::string &OutputFilename, bool DeleteOutput = false,
222 bool Quiet = false,
223 ArrayRef<std::string> ExtraArgs = {}) const;
224
225 /// runPasses - Just like the method above, but this just returns true or
226 /// false indicating whether or not the optimizer crashed on the specified
227 /// input (true = crashed). Does not produce any output.
228 bool runPasses(Module &M, const std::vector<std::string> &PassesToRun) const {
229 std::string Filename;
230 return runPasses(Program&: M, PassesToRun, OutputFilename&: Filename, DeleteOutput: true);
231 }
232
233 /// Take the specified pass list and create different combinations of passes
234 /// to compile the program with. Compile the program with each set and mark
235 /// test to see if it compiled correctly. If the passes compiled correctly
236 /// output nothing and rearrange the passes into a new order. If the passes
237 /// did not compile correctly, output the command required to recreate the
238 /// failure.
239 Error runManyPasses(const std::vector<std::string> &AllPasses);
240
241 /// This writes the current "Program" to the named bitcode file. If an error
242 /// occurs, true is returned.
243 bool writeProgramToFile(const std::string &Filename, const Module &M) const;
244 bool writeProgramToFile(const std::string &Filename, int FD,
245 const Module &M) const;
246 bool writeProgramToFile(int FD, const Module &M) const;
247
248private:
249 /// initializeExecutionEnvironment - This method is used to set up the
250 /// environment for executing LLVM programs.
251 Error initializeExecutionEnvironment();
252};
253
254struct DiscardTemp {
255 sys::fs::TempFile &File;
256 ~DiscardTemp();
257};
258
259/// Given a bitcode or assembly input filename, parse and return it, or return
260/// null if not possible.
261std::unique_ptr<Module> parseInputFile(StringRef InputFilename,
262 LLVMContext &ctxt);
263
264/// getPassesString - Turn a list of passes into a string which indicates the
265/// command line options that must be passed to add the passes.
266std::string getPassesString(const std::vector<std::string> &Passes);
267
268/// Prints out list of problematic functions
269void printFunctionList(const std::vector<Function *> &Funcs);
270
271/// Prints out list of problematic global variables
272void printGlobalVariableList(const std::vector<GlobalVariable *> &GVs);
273
274/// "Remove" the global variable by deleting its initializer, making it
275/// external.
276void deleteGlobalInitializer(GlobalVariable *GV);
277
278/// "Remove" the function by deleting all of it's basic blocks, making it
279/// external.
280void deleteFunctionBody(Function *F);
281
282/// Given a module and a list of functions in the module, split the functions
283/// OUT of the specified module, and place them in the new module.
284std::unique_ptr<Module>
285splitFunctionsOutOfModule(Module *M, const std::vector<Function *> &F,
286 ValueToValueMapTy &VMap);
287
288} // End llvm namespace
289
290#endif
291