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/Error.h"
20#include "llvm/Support/FileSystem.h"
21#include "llvm/Transforms/Utils/ValueMapper.h"
22#include <memory>
23#include <string>
24#include <vector>
25
26namespace llvm {
27
28class Module;
29class GlobalVariable;
30class Function;
31class BasicBlock;
32class AbstractInterpreter;
33class Instruction;
34class LLVMContext;
35
36class CC;
37
38extern bool DisableSimplifyCFG;
39
40/// BugpointIsInterrupted - Set to true when the user presses ctrl-c.
41///
42extern bool BugpointIsInterrupted;
43
44class BugDriver {
45 LLVMContext &Context;
46 const char *ToolName; // argv[0] of bugpoint
47 std::string ReferenceOutputFile; // Name of `good' output file
48 std::unique_ptr<Module> Program; // The raw program, linked together
49 std::vector<std::string> PassesToRun;
50 AbstractInterpreter *Interpreter; // How to run the program
51 AbstractInterpreter *SafeInterpreter; // To generate reference output, etc.
52 CC *cc;
53 bool run_find_bugs;
54 unsigned Timeout;
55 unsigned MemoryLimit;
56 bool UseValgrind;
57
58 // FIXME: sort out public/private distinctions...
59 friend class ReducePassList;
60 friend class ReduceMisCodegenFunctions;
61
62public:
63 BugDriver(const char *toolname, bool find_bugs, unsigned timeout,
64 unsigned memlimit, bool use_valgrind, LLVMContext &ctxt);
65 ~BugDriver();
66
67 const char *getToolName() const { return ToolName; }
68
69 LLVMContext &getContext() const { return Context; }
70
71 // Set up methods... these methods are used to copy information about the
72 // command line arguments into instance variables of BugDriver.
73 //
74 bool addSources(const std::vector<std::string> &FileNames);
75 void addPass(std::string p) { PassesToRun.push_back(x: std::move(p)); }
76 void setPassesToRun(const std::vector<std::string> &PTR) {
77 PassesToRun = PTR;
78 }
79 const std::vector<std::string> &getPassesToRun() const { return PassesToRun; }
80
81 /// run - The top level method that is invoked after all of the instance
82 /// variables are set up from command line arguments. The \p as_child argument
83 /// indicates whether the driver is to run in parent mode or child mode.
84 ///
85 Error run();
86
87 /// debugOptimizerCrash - This method is called when some optimizer pass
88 /// crashes on input. It attempts to prune down the testcase to something
89 /// reasonable, and figure out exactly which pass is crashing.
90 ///
91 Error debugOptimizerCrash(const std::string &ID = "passes");
92
93 /// debugCodeGeneratorCrash - This method is called when the code generator
94 /// crashes on an input. It attempts to reduce the input as much as possible
95 /// while still causing the code generator to crash.
96 Error debugCodeGeneratorCrash();
97
98 /// debugMiscompilation - This method is used when the passes selected are not
99 /// crashing, but the generated output is semantically different from the
100 /// input.
101 Error debugMiscompilation();
102
103 /// compileSharedObject - This method creates a SharedObject from a given
104 /// BitcodeFile for debugging a code generator.
105 ///
106 Expected<std::string> compileSharedObject(const std::string &BitcodeFile);
107
108 /// debugCodeGenerator - This method narrows down a module to a function or
109 /// set of functions, using the CBE as a ``safe'' code generator for other
110 /// functions that are not under consideration.
111 Error debugCodeGenerator();
112
113 /// isExecutingJIT - Returns true if bugpoint is currently testing the JIT
114 ///
115 bool isExecutingJIT();
116
117 Module &getProgram() const { return *Program; }
118
119 /// Set the current module to the specified module, returning the old one.
120 std::unique_ptr<Module> swapProgramIn(std::unique_ptr<Module> M);
121
122 AbstractInterpreter *switchToSafeInterpreter() {
123 AbstractInterpreter *Old = Interpreter;
124 Interpreter = (AbstractInterpreter *)SafeInterpreter;
125 return Old;
126 }
127
128 void switchToInterpreter(AbstractInterpreter *AI) { Interpreter = AI; }
129
130 /// If we reduce or update the program somehow, call this method to update
131 /// bugdriver with it. This deletes the old module and sets the specified one
132 /// as the current program.
133 void setNewProgram(std::unique_ptr<Module> M);
134
135 /// Try to compile the specified module. This is used for code generation
136 /// crash testing.
137 Error compileProgram(Module &M) const;
138
139 /// This method runs "Program", capturing the output of the program to a file.
140 /// A recommended filename may be optionally specified.
141 Expected<std::string> executeProgram(const Module &Program,
142 std::string OutputFilename,
143 std::string Bitcode,
144 const std::string &SharedObjects,
145 AbstractInterpreter *AI) const;
146
147 /// Used to create reference output with the "safe" backend, if reference
148 /// output is not provided. If there is a problem with the code generator
149 /// (e.g., llc crashes), this will return false and set Error.
150 Expected<std::string>
151 executeProgramSafely(const Module &Program,
152 const std::string &OutputFile) const;
153
154 /// Calls compileProgram and then records the output into ReferenceOutputFile.
155 /// Returns true if reference file created, false otherwise. Note:
156 /// initializeExecutionEnvironment should be called BEFORE this function.
157 Error createReferenceFile(Module &M, const std::string &Filename =
158 "bugpoint.reference.out-%%%%%%%");
159
160 /// This method executes the specified module and diffs the output against the
161 /// file specified by ReferenceOutputFile. If the output is different, 1 is
162 /// returned. If there is a problem with the code generator (e.g., llc
163 /// crashes), this will return -1 and set Error.
164 Expected<bool> diffProgram(const Module &Program,
165 const std::string &BitcodeFile = "",
166 const std::string &SharedObj = "",
167 bool RemoveBitcode = false) const;
168
169 /// This function is used to output M to a file named "bugpoint-ID.bc".
170 void EmitProgressBitcode(const Module &M, const std::string &ID,
171 bool NoFlyer = false) const;
172
173 /// This method clones the current Program and deletes the specified
174 /// instruction from the cloned module. It then runs a series of cleanup
175 /// passes (ADCE and SimplifyCFG) to eliminate any code which depends on the
176 /// value. The modified module is then returned.
177 ///
178 std::unique_ptr<Module> deleteInstructionFromProgram(const Instruction *I,
179 unsigned Simp);
180
181 /// This method clones the current Program and performs a series of cleanups
182 /// intended to get rid of extra cruft on the module. If the
183 /// MayModifySemantics argument is true, then the cleanups is allowed to
184 /// modify how the code behaves.
185 ///
186 std::unique_ptr<Module> performFinalCleanups(std::unique_ptr<Module> M,
187 bool MayModifySemantics = false);
188
189 /// Given a module, extract up to one loop from it into a new function. This
190 /// returns null if there are no extractable loops in the program or if the
191 /// loop extractor crashes.
192 std::unique_ptr<Module> extractLoop(Module *M);
193
194 /// Extract all but the specified basic blocks into their own functions. The
195 /// only detail is that M is actually a module cloned from the one the BBs are
196 /// in, so some mapping needs to be performed. If this operation fails for
197 /// some reason (ie the implementation is buggy), this function should return
198 /// null, otherwise it returns a new Module.
199 std::unique_ptr<Module>
200 extractMappedBlocksFromModule(const std::vector<BasicBlock *> &BBs,
201 Module *M);
202
203 /// Carefully run the specified set of pass on the specified/ module,
204 /// returning the transformed module on success, or a null pointer on failure.
205 std::unique_ptr<Module> runPassesOn(Module *M,
206 const std::vector<std::string> &Passes,
207 ArrayRef<std::string> ExtraArgs = {});
208
209 /// runPasses - Run the specified passes on Program, outputting a bitcode
210 /// file and writting the filename into OutputFile if successful. If the
211 /// optimizations fail for some reason (optimizer crashes), return true,
212 /// otherwise return false. If DeleteOutput is set to true, the bitcode is
213 /// deleted on success, and the filename string is undefined. This prints to
214 /// outs() a single line message indicating whether compilation was successful
215 /// or failed, unless Quiet is set. ExtraArgs specifies additional arguments
216 /// to pass to the child bugpoint instance.
217 ///
218 bool runPasses(Module &Program, const std::vector<std::string> &PassesToRun,
219 std::string &OutputFilename, bool DeleteOutput = false,
220 bool Quiet = false,
221 ArrayRef<std::string> ExtraArgs = {}) const;
222
223 /// runPasses - Just like the method above, but this just returns true or
224 /// false indicating whether or not the optimizer crashed on the specified
225 /// input (true = crashed). Does not produce any output.
226 ///
227 bool runPasses(Module &M, const std::vector<std::string> &PassesToRun) const {
228 std::string Filename;
229 return runPasses(Program&: M, PassesToRun, OutputFilename&: Filename, DeleteOutput: true);
230 }
231
232 /// Take the specified pass list and create different combinations of passes
233 /// to compile the program with. Compile the program with each set and mark
234 /// test to see if it compiled correctly. If the passes compiled correctly
235 /// output nothing and rearrange the passes into a new order. If the passes
236 /// did not compile correctly, output the command required to recreate the
237 /// failure.
238 Error runManyPasses(const std::vector<std::string> &AllPasses);
239
240 /// This writes the current "Program" to the named bitcode file. If an error
241 /// occurs, true is returned.
242 bool writeProgramToFile(const std::string &Filename, const Module &M) const;
243 bool writeProgramToFile(const std::string &Filename, int FD,
244 const Module &M) const;
245 bool writeProgramToFile(int FD, const Module &M) const;
246
247private:
248 /// initializeExecutionEnvironment - This method is used to set up the
249 /// environment for executing LLVM programs.
250 ///
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.
261///
262std::unique_ptr<Module> parseInputFile(StringRef InputFilename,
263 LLVMContext &ctxt);
264
265/// getPassesString - Turn a list of passes into a string which indicates the
266/// command line options that must be passed to add the passes.
267///
268std::string getPassesString(const std::vector<std::string> &Passes);
269
270/// PrintFunctionList - prints out list of problematic functions
271///
272void PrintFunctionList(const std::vector<Function *> &Funcs);
273
274/// PrintGlobalVariableList - prints out list of problematic global variables
275///
276void PrintGlobalVariableList(const std::vector<GlobalVariable *> &GVs);
277
278// DeleteGlobalInitializer - "Remove" the global variable by deleting its
279// initializer, making it external.
280//
281void DeleteGlobalInitializer(GlobalVariable *GV);
282
283// DeleteFunctionBody - "Remove" the function by deleting all of it's basic
284// blocks, making it external.
285//
286void DeleteFunctionBody(Function *F);
287
288/// Given a module and a list of functions in the module, split the functions
289/// OUT of the specified module, and place them in the new module.
290std::unique_ptr<Module>
291SplitFunctionsOutOfModule(Module *M, const std::vector<Function *> &F,
292 ValueToValueMapTy &VMap);
293
294} // End llvm namespace
295
296#endif
297