forked from OSchip/llvm-project
1433 lines
49 KiB
C++
1433 lines
49 KiB
C++
//===- CrashDebugger.cpp - Debug compilation crashes ----------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// This file defines the bugpoint internals that narrow down compilation crashes
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//
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//===----------------------------------------------------------------------===//
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#include "BugDriver.h"
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#include "ListReducer.h"
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#include "ToolRunner.h"
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#include "llvm/ADT/SmallPtrSet.h"
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#include "llvm/ADT/StringSet.h"
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#include "llvm/Analysis/TargetTransformInfo.h"
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#include "llvm/IR/CFG.h"
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#include "llvm/IR/Constants.h"
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#include "llvm/IR/DebugInfo.h"
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#include "llvm/IR/DerivedTypes.h"
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#include "llvm/IR/InstIterator.h"
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#include "llvm/IR/Instructions.h"
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#include "llvm/IR/LegacyPassManager.h"
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#include "llvm/IR/Module.h"
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#include "llvm/IR/ValueSymbolTable.h"
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#include "llvm/IR/Verifier.h"
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#include "llvm/Pass.h"
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#include "llvm/Support/CommandLine.h"
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#include "llvm/Support/FileUtilities.h"
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#include "llvm/Transforms/Scalar.h"
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#include "llvm/Transforms/Utils/BasicBlockUtils.h"
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#include "llvm/Transforms/Utils/Cloning.h"
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#include "llvm/Transforms/Utils/Local.h"
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#include <set>
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using namespace llvm;
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namespace {
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cl::opt<bool> KeepMain("keep-main",
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cl::desc("Force function reduction to keep main"),
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cl::init(false));
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cl::opt<bool> NoGlobalRM("disable-global-remove",
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cl::desc("Do not remove global variables"),
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cl::init(false));
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cl::opt<bool> NoAttributeRM("disable-attribute-remove",
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cl::desc("Do not remove function attributes"),
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cl::init(false));
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cl::opt<bool> ReplaceFuncsWithNull(
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"replace-funcs-with-null",
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cl::desc("When stubbing functions, replace all uses will null"),
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cl::init(false));
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cl::opt<bool> DontReducePassList("disable-pass-list-reduction",
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cl::desc("Skip pass list reduction steps"),
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cl::init(false));
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cl::opt<bool> NoNamedMDRM("disable-namedmd-remove",
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cl::desc("Do not remove global named metadata"),
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cl::init(false));
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cl::opt<bool> NoStripDebugInfo("disable-strip-debuginfo",
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cl::desc("Do not strip debug info metadata"),
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cl::init(false));
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cl::opt<bool> NoStripDebugTypeInfo("disable-strip-debug-types",
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cl::desc("Do not strip debug type info metadata"),
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cl::init(false));
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cl::opt<bool> VerboseErrors("verbose-errors",
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cl::desc("Print the output of crashing program"),
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cl::init(false));
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}
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namespace llvm {
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class ReducePassList : public ListReducer<std::string> {
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BugDriver &BD;
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public:
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ReducePassList(BugDriver &bd) : BD(bd) {}
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// Return true iff running the "removed" passes succeeds, and running the
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// "Kept" passes fail when run on the output of the "removed" passes. If we
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// return true, we update the current module of bugpoint.
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Expected<TestResult> doTest(std::vector<std::string> &Removed,
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std::vector<std::string> &Kept) override;
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};
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}
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Expected<ReducePassList::TestResult>
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ReducePassList::doTest(std::vector<std::string> &Prefix,
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std::vector<std::string> &Suffix) {
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std::string PrefixOutput;
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std::unique_ptr<Module> OrigProgram;
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if (!Prefix.empty()) {
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outs() << "Checking to see if these passes crash: "
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<< getPassesString(Prefix) << ": ";
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if (BD.runPasses(BD.getProgram(), Prefix, PrefixOutput))
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return KeepPrefix;
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OrigProgram = std::move(BD.Program);
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BD.Program = parseInputFile(PrefixOutput, BD.getContext());
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if (BD.Program == nullptr) {
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errs() << BD.getToolName() << ": Error reading bitcode file '"
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<< PrefixOutput << "'!\n";
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exit(1);
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}
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sys::fs::remove(PrefixOutput);
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}
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outs() << "Checking to see if these passes crash: " << getPassesString(Suffix)
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<< ": ";
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if (BD.runPasses(BD.getProgram(), Suffix))
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return KeepSuffix; // The suffix crashes alone...
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// Nothing failed, restore state...
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if (OrigProgram)
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BD.Program = std::move(OrigProgram);
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return NoFailure;
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}
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using BugTester = bool (*)(const BugDriver &, Module *);
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namespace {
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/// ReduceCrashingGlobalInitializers - This works by removing global variable
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/// initializers and seeing if the program still crashes. If it does, then we
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/// keep that program and try again.
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class ReduceCrashingGlobalInitializers : public ListReducer<GlobalVariable *> {
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BugDriver &BD;
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BugTester TestFn;
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public:
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ReduceCrashingGlobalInitializers(BugDriver &bd, BugTester testFn)
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: BD(bd), TestFn(testFn) {}
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Expected<TestResult> doTest(std::vector<GlobalVariable *> &Prefix,
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std::vector<GlobalVariable *> &Kept) override {
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if (!Kept.empty() && TestGlobalVariables(Kept))
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return KeepSuffix;
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if (!Prefix.empty() && TestGlobalVariables(Prefix))
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return KeepPrefix;
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return NoFailure;
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}
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bool TestGlobalVariables(std::vector<GlobalVariable *> &GVs);
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};
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}
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bool ReduceCrashingGlobalInitializers::TestGlobalVariables(
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std::vector<GlobalVariable *> &GVs) {
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// Clone the program to try hacking it apart...
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ValueToValueMapTy VMap;
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std::unique_ptr<Module> M = CloneModule(BD.getProgram(), VMap);
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// Convert list to set for fast lookup...
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std::set<GlobalVariable *> GVSet;
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for (unsigned i = 0, e = GVs.size(); i != e; ++i) {
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GlobalVariable *CMGV = cast<GlobalVariable>(VMap[GVs[i]]);
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assert(CMGV && "Global Variable not in module?!");
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GVSet.insert(CMGV);
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}
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outs() << "Checking for crash with only these global variables: ";
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PrintGlobalVariableList(GVs);
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outs() << ": ";
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// Loop over and delete any global variables which we aren't supposed to be
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// playing with...
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for (GlobalVariable &I : M->globals())
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if (I.hasInitializer() && !GVSet.count(&I)) {
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DeleteGlobalInitializer(&I);
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I.setLinkage(GlobalValue::ExternalLinkage);
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I.setComdat(nullptr);
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}
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// Try running the hacked up program...
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if (TestFn(BD, M.get())) {
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BD.setNewProgram(std::move(M)); // It crashed, keep the trimmed version...
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// Make sure to use global variable pointers that point into the now-current
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// module.
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GVs.assign(GVSet.begin(), GVSet.end());
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return true;
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}
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return false;
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}
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namespace {
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/// ReduceCrashingFunctions reducer - This works by removing functions and
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/// seeing if the program still crashes. If it does, then keep the newer,
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/// smaller program.
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///
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class ReduceCrashingFunctions : public ListReducer<Function *> {
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BugDriver &BD;
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BugTester TestFn;
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public:
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ReduceCrashingFunctions(BugDriver &bd, BugTester testFn)
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: BD(bd), TestFn(testFn) {}
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Expected<TestResult> doTest(std::vector<Function *> &Prefix,
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std::vector<Function *> &Kept) override {
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if (!Kept.empty() && TestFuncs(Kept))
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return KeepSuffix;
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if (!Prefix.empty() && TestFuncs(Prefix))
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return KeepPrefix;
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return NoFailure;
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}
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bool TestFuncs(std::vector<Function *> &Prefix);
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};
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}
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static void RemoveFunctionReferences(Module *M, const char *Name) {
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auto *UsedVar = M->getGlobalVariable(Name, true);
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if (!UsedVar || !UsedVar->hasInitializer())
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return;
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if (isa<ConstantAggregateZero>(UsedVar->getInitializer())) {
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assert(UsedVar->use_empty());
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UsedVar->eraseFromParent();
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return;
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}
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auto *OldUsedVal = cast<ConstantArray>(UsedVar->getInitializer());
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std::vector<Constant *> Used;
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for (Value *V : OldUsedVal->operand_values()) {
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Constant *Op = cast<Constant>(V->stripPointerCasts());
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if (!Op->isNullValue()) {
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Used.push_back(cast<Constant>(V));
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}
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}
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auto *NewValElemTy = OldUsedVal->getType()->getElementType();
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auto *NewValTy = ArrayType::get(NewValElemTy, Used.size());
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auto *NewUsedVal = ConstantArray::get(NewValTy, Used);
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UsedVar->mutateType(NewUsedVal->getType()->getPointerTo());
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UsedVar->setInitializer(NewUsedVal);
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}
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bool ReduceCrashingFunctions::TestFuncs(std::vector<Function *> &Funcs) {
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// If main isn't present, claim there is no problem.
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if (KeepMain && !is_contained(Funcs, BD.getProgram().getFunction("main")))
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return false;
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// Clone the program to try hacking it apart...
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ValueToValueMapTy VMap;
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std::unique_ptr<Module> M = CloneModule(BD.getProgram(), VMap);
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// Convert list to set for fast lookup...
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std::set<Function *> Functions;
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for (unsigned i = 0, e = Funcs.size(); i != e; ++i) {
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Function *CMF = cast<Function>(VMap[Funcs[i]]);
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assert(CMF && "Function not in module?!");
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assert(CMF->getFunctionType() == Funcs[i]->getFunctionType() && "wrong ty");
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assert(CMF->getName() == Funcs[i]->getName() && "wrong name");
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Functions.insert(CMF);
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}
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outs() << "Checking for crash with only these functions: ";
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PrintFunctionList(Funcs);
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outs() << ": ";
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if (!ReplaceFuncsWithNull) {
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// Loop over and delete any functions which we aren't supposed to be playing
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// with...
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for (Function &I : *M)
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if (!I.isDeclaration() && !Functions.count(&I))
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DeleteFunctionBody(&I);
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} else {
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std::vector<GlobalValue *> ToRemove;
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// First, remove aliases to functions we're about to purge.
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for (GlobalAlias &Alias : M->aliases()) {
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GlobalObject *Root = Alias.getBaseObject();
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Function *F = dyn_cast_or_null<Function>(Root);
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if (F) {
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if (Functions.count(F))
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// We're keeping this function.
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continue;
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} else if (Root->isNullValue()) {
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// This referenced a globalalias that we've already replaced,
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// so we still need to replace this alias.
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} else if (!F) {
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// Not a function, therefore not something we mess with.
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continue;
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}
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PointerType *Ty = cast<PointerType>(Alias.getType());
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Constant *Replacement = ConstantPointerNull::get(Ty);
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Alias.replaceAllUsesWith(Replacement);
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ToRemove.push_back(&Alias);
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}
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for (Function &I : *M) {
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if (!I.isDeclaration() && !Functions.count(&I)) {
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PointerType *Ty = cast<PointerType>(I.getType());
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Constant *Replacement = ConstantPointerNull::get(Ty);
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I.replaceAllUsesWith(Replacement);
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ToRemove.push_back(&I);
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}
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}
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for (auto *F : ToRemove) {
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F->eraseFromParent();
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}
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// Finally, remove any null members from any global intrinsic.
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RemoveFunctionReferences(M.get(), "llvm.used");
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RemoveFunctionReferences(M.get(), "llvm.compiler.used");
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}
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// Try running the hacked up program...
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if (TestFn(BD, M.get())) {
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BD.setNewProgram(std::move(M)); // It crashed, keep the trimmed version...
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// Make sure to use function pointers that point into the now-current
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// module.
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Funcs.assign(Functions.begin(), Functions.end());
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return true;
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}
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return false;
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}
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namespace {
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/// ReduceCrashingFunctionAttributes reducer - This works by removing
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/// attributes on a particular function and seeing if the program still crashes.
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/// If it does, then keep the newer, smaller program.
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///
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class ReduceCrashingFunctionAttributes : public ListReducer<Attribute> {
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BugDriver &BD;
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std::string FnName;
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BugTester TestFn;
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public:
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ReduceCrashingFunctionAttributes(BugDriver &bd, const std::string &FnName,
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BugTester testFn)
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: BD(bd), FnName(FnName), TestFn(testFn) {}
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Expected<TestResult> doTest(std::vector<Attribute> &Prefix,
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std::vector<Attribute> &Kept) override {
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if (!Kept.empty() && TestFuncAttrs(Kept))
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return KeepSuffix;
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if (!Prefix.empty() && TestFuncAttrs(Prefix))
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return KeepPrefix;
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return NoFailure;
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}
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bool TestFuncAttrs(std::vector<Attribute> &Attrs);
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};
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}
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bool ReduceCrashingFunctionAttributes::TestFuncAttrs(
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std::vector<Attribute> &Attrs) {
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// Clone the program to try hacking it apart...
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std::unique_ptr<Module> M = CloneModule(BD.getProgram());
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Function *F = M->getFunction(FnName);
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// Build up an AttributeList from the attributes we've been given by the
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// reducer.
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AttrBuilder AB;
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for (auto A : Attrs)
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AB.addAttribute(A);
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AttributeList NewAttrs;
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NewAttrs =
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NewAttrs.addAttributes(BD.getContext(), AttributeList::FunctionIndex, AB);
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// Set this new list of attributes on the function.
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F->setAttributes(NewAttrs);
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// If the attribute list includes "optnone" we need to make sure it also
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// includes "noinline" otherwise we will get a verifier failure.
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if (F->hasFnAttribute(Attribute::OptimizeNone))
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F->addFnAttr(Attribute::NoInline);
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// Try running on the hacked up program...
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if (TestFn(BD, M.get())) {
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BD.setNewProgram(std::move(M)); // It crashed, keep the trimmed version...
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// Pass along the set of attributes that caused the crash.
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Attrs.clear();
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for (Attribute A : NewAttrs.getFnAttributes()) {
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Attrs.push_back(A);
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}
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return true;
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}
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return false;
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}
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namespace {
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/// Simplify the CFG without completely destroying it.
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/// This is not well defined, but basically comes down to "try to eliminate
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/// unreachable blocks and constant fold terminators without deciding that
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/// certain undefined behavior cuts off the program at the legs".
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void simpleSimplifyCfg(Function &F, SmallVectorImpl<BasicBlock *> &BBs) {
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if (F.empty())
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return;
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for (auto *BB : BBs) {
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ConstantFoldTerminator(BB);
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MergeBlockIntoPredecessor(BB);
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}
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// Remove unreachable blocks
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// removeUnreachableBlocks can't be used here, it will turn various
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// undefined behavior into unreachables, but bugpoint was the thing that
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// generated the undefined behavior, and we don't want it to kill the entire
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// program.
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SmallPtrSet<BasicBlock *, 16> Visited;
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for (auto *BB : depth_first(&F.getEntryBlock()))
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Visited.insert(BB);
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SmallVector<BasicBlock *, 16> Unreachable;
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for (auto &BB : F)
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if (!Visited.count(&BB))
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Unreachable.push_back(&BB);
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// The dead BB's may be in a dead cycle or otherwise have references to each
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// other. Because of this, we have to drop all references first, then delete
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// them all at once.
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for (auto *BB : Unreachable) {
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for (BasicBlock *Successor : successors(&*BB))
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if (Visited.count(Successor))
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Successor->removePredecessor(&*BB);
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BB->dropAllReferences();
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}
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for (auto *BB : Unreachable)
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BB->eraseFromParent();
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}
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/// ReduceCrashingBlocks reducer - This works by setting the terminators of
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/// all terminators except the specified basic blocks to a 'ret' instruction,
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/// then running the simplify-cfg pass. This has the effect of chopping up
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/// the CFG really fast which can reduce large functions quickly.
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///
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class ReduceCrashingBlocks : public ListReducer<const BasicBlock *> {
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BugDriver &BD;
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BugTester TestFn;
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public:
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ReduceCrashingBlocks(BugDriver &BD, BugTester testFn)
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: BD(BD), TestFn(testFn) {}
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Expected<TestResult> doTest(std::vector<const BasicBlock *> &Prefix,
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std::vector<const BasicBlock *> &Kept) override {
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if (!Kept.empty() && TestBlocks(Kept))
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return KeepSuffix;
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if (!Prefix.empty() && TestBlocks(Prefix))
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return KeepPrefix;
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return NoFailure;
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}
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bool TestBlocks(std::vector<const BasicBlock *> &Prefix);
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};
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}
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bool ReduceCrashingBlocks::TestBlocks(std::vector<const BasicBlock *> &BBs) {
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// Clone the program to try hacking it apart...
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ValueToValueMapTy VMap;
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std::unique_ptr<Module> M = CloneModule(BD.getProgram(), VMap);
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// Convert list to set for fast lookup...
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SmallPtrSet<BasicBlock *, 8> Blocks;
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for (unsigned i = 0, e = BBs.size(); i != e; ++i)
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Blocks.insert(cast<BasicBlock>(VMap[BBs[i]]));
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outs() << "Checking for crash with only these blocks:";
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unsigned NumPrint = Blocks.size();
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if (NumPrint > 10)
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NumPrint = 10;
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for (unsigned i = 0, e = NumPrint; i != e; ++i)
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outs() << " " << BBs[i]->getName();
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if (NumPrint < Blocks.size())
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outs() << "... <" << Blocks.size() << " total>";
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outs() << ": ";
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// Loop over and delete any hack up any blocks that are not listed...
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for (Function &F : M->functions()) {
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for (BasicBlock &BB : F) {
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if (!Blocks.count(&BB) && BB.getTerminator()->getNumSuccessors()) {
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// Loop over all of the successors of this block, deleting any PHI nodes
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// that might include it.
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for (BasicBlock *Succ : successors(&BB))
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Succ->removePredecessor(&BB);
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Instruction *BBTerm = BB.getTerminator();
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if (BBTerm->isEHPad() || BBTerm->getType()->isTokenTy())
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continue;
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if (!BBTerm->getType()->isVoidTy())
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BBTerm->replaceAllUsesWith(Constant::getNullValue(BBTerm->getType()));
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// Replace the old terminator instruction.
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BB.getInstList().pop_back();
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new UnreachableInst(BB.getContext(), &BB);
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}
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}
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}
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|
|
|
// The CFG Simplifier pass may delete one of the basic blocks we are
|
|
// interested in. If it does we need to take the block out of the list. Make
|
|
// a "persistent mapping" by turning basic blocks into <function, name> pairs.
|
|
// This won't work well if blocks are unnamed, but that is just the risk we
|
|
// have to take. FIXME: Can we just name the blocks?
|
|
std::vector<std::pair<std::string, std::string>> BlockInfo;
|
|
|
|
for (BasicBlock *BB : Blocks)
|
|
BlockInfo.emplace_back(std::string(BB->getParent()->getName()),
|
|
std::string(BB->getName()));
|
|
|
|
SmallVector<BasicBlock *, 16> ToProcess;
|
|
for (auto &F : *M) {
|
|
for (auto &BB : F)
|
|
if (!Blocks.count(&BB))
|
|
ToProcess.push_back(&BB);
|
|
simpleSimplifyCfg(F, ToProcess);
|
|
ToProcess.clear();
|
|
}
|
|
// Verify we didn't break anything
|
|
std::vector<std::string> Passes;
|
|
Passes.push_back("verify");
|
|
std::unique_ptr<Module> New = BD.runPassesOn(M.get(), Passes);
|
|
if (!New) {
|
|
errs() << "verify failed!\n";
|
|
exit(1);
|
|
}
|
|
M = std::move(New);
|
|
|
|
// Try running on the hacked up program...
|
|
if (TestFn(BD, M.get())) {
|
|
BD.setNewProgram(std::move(M)); // It crashed, keep the trimmed version...
|
|
|
|
// Make sure to use basic block pointers that point into the now-current
|
|
// module, and that they don't include any deleted blocks.
|
|
BBs.clear();
|
|
const ValueSymbolTable &GST = BD.getProgram().getValueSymbolTable();
|
|
for (const auto &BI : BlockInfo) {
|
|
Function *F = cast<Function>(GST.lookup(BI.first));
|
|
Value *V = F->getValueSymbolTable()->lookup(BI.second);
|
|
if (V && V->getType() == Type::getLabelTy(V->getContext()))
|
|
BBs.push_back(cast<BasicBlock>(V));
|
|
}
|
|
return true;
|
|
}
|
|
// It didn't crash, try something else.
|
|
return false;
|
|
}
|
|
|
|
namespace {
|
|
/// ReduceCrashingConditionals reducer - This works by changing
|
|
/// conditional branches to unconditional ones, then simplifying the CFG
|
|
/// This has the effect of chopping up the CFG really fast which can reduce
|
|
/// large functions quickly.
|
|
///
|
|
class ReduceCrashingConditionals : public ListReducer<const BasicBlock *> {
|
|
BugDriver &BD;
|
|
BugTester TestFn;
|
|
bool Direction;
|
|
|
|
public:
|
|
ReduceCrashingConditionals(BugDriver &bd, BugTester testFn, bool Direction)
|
|
: BD(bd), TestFn(testFn), Direction(Direction) {}
|
|
|
|
Expected<TestResult> doTest(std::vector<const BasicBlock *> &Prefix,
|
|
std::vector<const BasicBlock *> &Kept) override {
|
|
if (!Kept.empty() && TestBlocks(Kept))
|
|
return KeepSuffix;
|
|
if (!Prefix.empty() && TestBlocks(Prefix))
|
|
return KeepPrefix;
|
|
return NoFailure;
|
|
}
|
|
|
|
bool TestBlocks(std::vector<const BasicBlock *> &Prefix);
|
|
};
|
|
}
|
|
|
|
bool ReduceCrashingConditionals::TestBlocks(
|
|
std::vector<const BasicBlock *> &BBs) {
|
|
// Clone the program to try hacking it apart...
|
|
ValueToValueMapTy VMap;
|
|
std::unique_ptr<Module> M = CloneModule(BD.getProgram(), VMap);
|
|
|
|
// Convert list to set for fast lookup...
|
|
SmallPtrSet<const BasicBlock *, 8> Blocks;
|
|
for (const auto *BB : BBs)
|
|
Blocks.insert(cast<BasicBlock>(VMap[BB]));
|
|
|
|
outs() << "Checking for crash with changing conditionals to always jump to "
|
|
<< (Direction ? "true" : "false") << ":";
|
|
unsigned NumPrint = Blocks.size();
|
|
if (NumPrint > 10)
|
|
NumPrint = 10;
|
|
for (unsigned i = 0, e = NumPrint; i != e; ++i)
|
|
outs() << " " << BBs[i]->getName();
|
|
if (NumPrint < Blocks.size())
|
|
outs() << "... <" << Blocks.size() << " total>";
|
|
outs() << ": ";
|
|
|
|
// Loop over and delete any hack up any blocks that are not listed...
|
|
for (auto &F : *M)
|
|
for (auto &BB : F)
|
|
if (!Blocks.count(&BB)) {
|
|
auto *BR = dyn_cast<BranchInst>(BB.getTerminator());
|
|
if (!BR || !BR->isConditional())
|
|
continue;
|
|
if (Direction)
|
|
BR->setCondition(ConstantInt::getTrue(BR->getContext()));
|
|
else
|
|
BR->setCondition(ConstantInt::getFalse(BR->getContext()));
|
|
}
|
|
|
|
// The following may destroy some blocks, so we save them first
|
|
std::vector<std::pair<std::string, std::string>> BlockInfo;
|
|
|
|
for (const BasicBlock *BB : Blocks)
|
|
BlockInfo.emplace_back(std::string(BB->getParent()->getName()),
|
|
std::string(BB->getName()));
|
|
|
|
SmallVector<BasicBlock *, 16> ToProcess;
|
|
for (auto &F : *M) {
|
|
for (auto &BB : F)
|
|
if (!Blocks.count(&BB))
|
|
ToProcess.push_back(&BB);
|
|
simpleSimplifyCfg(F, ToProcess);
|
|
ToProcess.clear();
|
|
}
|
|
// Verify we didn't break anything
|
|
std::vector<std::string> Passes;
|
|
Passes.push_back("verify");
|
|
std::unique_ptr<Module> New = BD.runPassesOn(M.get(), Passes);
|
|
if (!New) {
|
|
errs() << "verify failed!\n";
|
|
exit(1);
|
|
}
|
|
M = std::move(New);
|
|
|
|
// Try running on the hacked up program...
|
|
if (TestFn(BD, M.get())) {
|
|
BD.setNewProgram(std::move(M)); // It crashed, keep the trimmed version...
|
|
|
|
// Make sure to use basic block pointers that point into the now-current
|
|
// module, and that they don't include any deleted blocks.
|
|
BBs.clear();
|
|
const ValueSymbolTable &GST = BD.getProgram().getValueSymbolTable();
|
|
for (auto &BI : BlockInfo) {
|
|
auto *F = cast<Function>(GST.lookup(BI.first));
|
|
Value *V = F->getValueSymbolTable()->lookup(BI.second);
|
|
if (V && V->getType() == Type::getLabelTy(V->getContext()))
|
|
BBs.push_back(cast<BasicBlock>(V));
|
|
}
|
|
return true;
|
|
}
|
|
// It didn't crash, try something else.
|
|
return false;
|
|
}
|
|
|
|
namespace {
|
|
/// SimplifyCFG reducer - This works by calling SimplifyCFG on each basic block
|
|
/// in the program.
|
|
|
|
class ReduceSimplifyCFG : public ListReducer<const BasicBlock *> {
|
|
BugDriver &BD;
|
|
BugTester TestFn;
|
|
TargetTransformInfo TTI;
|
|
|
|
public:
|
|
ReduceSimplifyCFG(BugDriver &bd, BugTester testFn)
|
|
: BD(bd), TestFn(testFn), TTI(bd.getProgram().getDataLayout()) {}
|
|
|
|
Expected<TestResult> doTest(std::vector<const BasicBlock *> &Prefix,
|
|
std::vector<const BasicBlock *> &Kept) override {
|
|
if (!Kept.empty() && TestBlocks(Kept))
|
|
return KeepSuffix;
|
|
if (!Prefix.empty() && TestBlocks(Prefix))
|
|
return KeepPrefix;
|
|
return NoFailure;
|
|
}
|
|
|
|
bool TestBlocks(std::vector<const BasicBlock *> &Prefix);
|
|
};
|
|
}
|
|
|
|
bool ReduceSimplifyCFG::TestBlocks(std::vector<const BasicBlock *> &BBs) {
|
|
// Clone the program to try hacking it apart...
|
|
ValueToValueMapTy VMap;
|
|
std::unique_ptr<Module> M = CloneModule(BD.getProgram(), VMap);
|
|
|
|
// Convert list to set for fast lookup...
|
|
SmallPtrSet<const BasicBlock *, 8> Blocks;
|
|
for (const auto *BB : BBs)
|
|
Blocks.insert(cast<BasicBlock>(VMap[BB]));
|
|
|
|
outs() << "Checking for crash with CFG simplifying:";
|
|
unsigned NumPrint = Blocks.size();
|
|
if (NumPrint > 10)
|
|
NumPrint = 10;
|
|
for (unsigned i = 0, e = NumPrint; i != e; ++i)
|
|
outs() << " " << BBs[i]->getName();
|
|
if (NumPrint < Blocks.size())
|
|
outs() << "... <" << Blocks.size() << " total>";
|
|
outs() << ": ";
|
|
|
|
// The following may destroy some blocks, so we save them first
|
|
std::vector<std::pair<std::string, std::string>> BlockInfo;
|
|
|
|
for (const BasicBlock *BB : Blocks)
|
|
BlockInfo.emplace_back(std::string(BB->getParent()->getName()),
|
|
std::string(BB->getName()));
|
|
|
|
// Loop over and delete any hack up any blocks that are not listed...
|
|
for (auto &F : *M)
|
|
// Loop over all of the basic blocks and remove them if they are unneeded.
|
|
for (Function::iterator BBIt = F.begin(); BBIt != F.end();) {
|
|
if (!Blocks.count(&*BBIt)) {
|
|
++BBIt;
|
|
continue;
|
|
}
|
|
simplifyCFG(&*BBIt++, TTI);
|
|
}
|
|
// Verify we didn't break anything
|
|
std::vector<std::string> Passes;
|
|
Passes.push_back("verify");
|
|
std::unique_ptr<Module> New = BD.runPassesOn(M.get(), Passes);
|
|
if (!New) {
|
|
errs() << "verify failed!\n";
|
|
exit(1);
|
|
}
|
|
M = std::move(New);
|
|
|
|
// Try running on the hacked up program...
|
|
if (TestFn(BD, M.get())) {
|
|
BD.setNewProgram(std::move(M)); // It crashed, keep the trimmed version...
|
|
|
|
// Make sure to use basic block pointers that point into the now-current
|
|
// module, and that they don't include any deleted blocks.
|
|
BBs.clear();
|
|
const ValueSymbolTable &GST = BD.getProgram().getValueSymbolTable();
|
|
for (auto &BI : BlockInfo) {
|
|
auto *F = cast<Function>(GST.lookup(BI.first));
|
|
Value *V = F->getValueSymbolTable()->lookup(BI.second);
|
|
if (V && V->getType() == Type::getLabelTy(V->getContext()))
|
|
BBs.push_back(cast<BasicBlock>(V));
|
|
}
|
|
return true;
|
|
}
|
|
// It didn't crash, try something else.
|
|
return false;
|
|
}
|
|
|
|
namespace {
|
|
/// ReduceCrashingInstructions reducer - This works by removing the specified
|
|
/// non-terminator instructions and replacing them with undef.
|
|
///
|
|
class ReduceCrashingInstructions : public ListReducer<const Instruction *> {
|
|
BugDriver &BD;
|
|
BugTester TestFn;
|
|
|
|
public:
|
|
ReduceCrashingInstructions(BugDriver &bd, BugTester testFn)
|
|
: BD(bd), TestFn(testFn) {}
|
|
|
|
Expected<TestResult> doTest(std::vector<const Instruction *> &Prefix,
|
|
std::vector<const Instruction *> &Kept) override {
|
|
if (!Kept.empty() && TestInsts(Kept))
|
|
return KeepSuffix;
|
|
if (!Prefix.empty() && TestInsts(Prefix))
|
|
return KeepPrefix;
|
|
return NoFailure;
|
|
}
|
|
|
|
bool TestInsts(std::vector<const Instruction *> &Prefix);
|
|
};
|
|
}
|
|
|
|
bool ReduceCrashingInstructions::TestInsts(
|
|
std::vector<const Instruction *> &Insts) {
|
|
// Clone the program to try hacking it apart...
|
|
ValueToValueMapTy VMap;
|
|
std::unique_ptr<Module> M = CloneModule(BD.getProgram(), VMap);
|
|
|
|
// Convert list to set for fast lookup...
|
|
SmallPtrSet<Instruction *, 32> Instructions;
|
|
for (unsigned i = 0, e = Insts.size(); i != e; ++i) {
|
|
assert(!Insts[i]->isTerminator());
|
|
Instructions.insert(cast<Instruction>(VMap[Insts[i]]));
|
|
}
|
|
|
|
outs() << "Checking for crash with only " << Instructions.size();
|
|
if (Instructions.size() == 1)
|
|
outs() << " instruction: ";
|
|
else
|
|
outs() << " instructions: ";
|
|
|
|
for (Module::iterator MI = M->begin(), ME = M->end(); MI != ME; ++MI)
|
|
for (Function::iterator FI = MI->begin(), FE = MI->end(); FI != FE; ++FI)
|
|
for (BasicBlock::iterator I = FI->begin(), E = FI->end(); I != E;) {
|
|
Instruction *Inst = &*I++;
|
|
if (!Instructions.count(Inst) && !Inst->isTerminator() &&
|
|
!Inst->isEHPad() && !Inst->getType()->isTokenTy() &&
|
|
!Inst->isSwiftError()) {
|
|
if (!Inst->getType()->isVoidTy())
|
|
Inst->replaceAllUsesWith(UndefValue::get(Inst->getType()));
|
|
Inst->eraseFromParent();
|
|
}
|
|
}
|
|
|
|
// Verify that this is still valid.
|
|
legacy::PassManager Passes;
|
|
Passes.add(createVerifierPass(/*FatalErrors=*/false));
|
|
Passes.run(*M);
|
|
|
|
// Try running on the hacked up program...
|
|
if (TestFn(BD, M.get())) {
|
|
BD.setNewProgram(std::move(M)); // It crashed, keep the trimmed version...
|
|
|
|
// Make sure to use instruction pointers that point into the now-current
|
|
// module, and that they don't include any deleted blocks.
|
|
Insts.clear();
|
|
for (Instruction *Inst : Instructions)
|
|
Insts.push_back(Inst);
|
|
return true;
|
|
}
|
|
// It didn't crash, try something else.
|
|
return false;
|
|
}
|
|
|
|
namespace {
|
|
/// ReduceCrashingMetadata reducer - This works by removing all metadata from
|
|
/// the specified instructions.
|
|
///
|
|
class ReduceCrashingMetadata : public ListReducer<Instruction *> {
|
|
BugDriver &BD;
|
|
BugTester TestFn;
|
|
|
|
public:
|
|
ReduceCrashingMetadata(BugDriver &bd, BugTester testFn)
|
|
: BD(bd), TestFn(testFn) {}
|
|
|
|
Expected<TestResult> doTest(std::vector<Instruction *> &Prefix,
|
|
std::vector<Instruction *> &Kept) override {
|
|
if (!Kept.empty() && TestInsts(Kept))
|
|
return KeepSuffix;
|
|
if (!Prefix.empty() && TestInsts(Prefix))
|
|
return KeepPrefix;
|
|
return NoFailure;
|
|
}
|
|
|
|
bool TestInsts(std::vector<Instruction *> &Prefix);
|
|
};
|
|
} // namespace
|
|
|
|
bool ReduceCrashingMetadata::TestInsts(std::vector<Instruction *> &Insts) {
|
|
// Clone the program to try hacking it apart...
|
|
ValueToValueMapTy VMap;
|
|
std::unique_ptr<Module> M = CloneModule(BD.getProgram(), VMap);
|
|
|
|
// Convert list to set for fast lookup...
|
|
SmallPtrSet<Instruction *, 32> Instructions;
|
|
for (Instruction *I : Insts)
|
|
Instructions.insert(cast<Instruction>(VMap[I]));
|
|
|
|
outs() << "Checking for crash with metadata retained from "
|
|
<< Instructions.size();
|
|
if (Instructions.size() == 1)
|
|
outs() << " instruction: ";
|
|
else
|
|
outs() << " instructions: ";
|
|
|
|
// Try to drop instruction metadata from all instructions, except the ones
|
|
// selected in Instructions.
|
|
for (Function &F : *M)
|
|
for (Instruction &Inst : instructions(F)) {
|
|
if (!Instructions.count(&Inst)) {
|
|
Inst.dropUnknownNonDebugMetadata();
|
|
Inst.setDebugLoc({});
|
|
}
|
|
}
|
|
|
|
// Verify that this is still valid.
|
|
legacy::PassManager Passes;
|
|
Passes.add(createVerifierPass(/*FatalErrors=*/false));
|
|
Passes.run(*M);
|
|
|
|
// Try running on the hacked up program...
|
|
if (TestFn(BD, M.get())) {
|
|
BD.setNewProgram(std::move(M)); // It crashed, keep the trimmed version...
|
|
|
|
// Make sure to use instruction pointers that point into the now-current
|
|
// module, and that they don't include any deleted blocks.
|
|
Insts.clear();
|
|
for (Instruction *I : Instructions)
|
|
Insts.push_back(I);
|
|
return true;
|
|
}
|
|
// It didn't crash, try something else.
|
|
return false;
|
|
}
|
|
|
|
namespace {
|
|
// Reduce the list of Named Metadata nodes. We keep this as a list of
|
|
// names to avoid having to convert back and forth every time.
|
|
class ReduceCrashingNamedMD : public ListReducer<std::string> {
|
|
BugDriver &BD;
|
|
BugTester TestFn;
|
|
|
|
public:
|
|
ReduceCrashingNamedMD(BugDriver &bd, BugTester testFn)
|
|
: BD(bd), TestFn(testFn) {}
|
|
|
|
Expected<TestResult> doTest(std::vector<std::string> &Prefix,
|
|
std::vector<std::string> &Kept) override {
|
|
if (!Kept.empty() && TestNamedMDs(Kept))
|
|
return KeepSuffix;
|
|
if (!Prefix.empty() && TestNamedMDs(Prefix))
|
|
return KeepPrefix;
|
|
return NoFailure;
|
|
}
|
|
|
|
bool TestNamedMDs(std::vector<std::string> &NamedMDs);
|
|
};
|
|
}
|
|
|
|
bool ReduceCrashingNamedMD::TestNamedMDs(std::vector<std::string> &NamedMDs) {
|
|
|
|
ValueToValueMapTy VMap;
|
|
std::unique_ptr<Module> M = CloneModule(BD.getProgram(), VMap);
|
|
|
|
outs() << "Checking for crash with only these named metadata nodes:";
|
|
unsigned NumPrint = std::min<size_t>(NamedMDs.size(), 10);
|
|
for (unsigned i = 0, e = NumPrint; i != e; ++i)
|
|
outs() << " " << NamedMDs[i];
|
|
if (NumPrint < NamedMDs.size())
|
|
outs() << "... <" << NamedMDs.size() << " total>";
|
|
outs() << ": ";
|
|
|
|
// Make a StringMap for faster lookup
|
|
StringSet<> Names;
|
|
for (const std::string &Name : NamedMDs)
|
|
Names.insert(Name);
|
|
|
|
// First collect all the metadata to delete in a vector, then
|
|
// delete them all at once to avoid invalidating the iterator
|
|
std::vector<NamedMDNode *> ToDelete;
|
|
ToDelete.reserve(M->named_metadata_size() - Names.size());
|
|
for (auto &NamedMD : M->named_metadata())
|
|
// Always keep a nonempty llvm.dbg.cu because the Verifier would complain.
|
|
if (!Names.count(NamedMD.getName()) &&
|
|
(!(NamedMD.getName() == "llvm.dbg.cu" && NamedMD.getNumOperands() > 0)))
|
|
ToDelete.push_back(&NamedMD);
|
|
|
|
for (auto *NamedMD : ToDelete)
|
|
NamedMD->eraseFromParent();
|
|
|
|
// Verify that this is still valid.
|
|
legacy::PassManager Passes;
|
|
Passes.add(createVerifierPass(/*FatalErrors=*/false));
|
|
Passes.run(*M);
|
|
|
|
// Try running on the hacked up program...
|
|
if (TestFn(BD, M.get())) {
|
|
BD.setNewProgram(std::move(M)); // It crashed, keep the trimmed version...
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
namespace {
|
|
// Reduce the list of operands to named metadata nodes
|
|
class ReduceCrashingNamedMDOps : public ListReducer<const MDNode *> {
|
|
BugDriver &BD;
|
|
BugTester TestFn;
|
|
|
|
public:
|
|
ReduceCrashingNamedMDOps(BugDriver &bd, BugTester testFn)
|
|
: BD(bd), TestFn(testFn) {}
|
|
|
|
Expected<TestResult> doTest(std::vector<const MDNode *> &Prefix,
|
|
std::vector<const MDNode *> &Kept) override {
|
|
if (!Kept.empty() && TestNamedMDOps(Kept))
|
|
return KeepSuffix;
|
|
if (!Prefix.empty() && TestNamedMDOps(Prefix))
|
|
return KeepPrefix;
|
|
return NoFailure;
|
|
}
|
|
|
|
bool TestNamedMDOps(std::vector<const MDNode *> &NamedMDOps);
|
|
};
|
|
}
|
|
|
|
bool ReduceCrashingNamedMDOps::TestNamedMDOps(
|
|
std::vector<const MDNode *> &NamedMDOps) {
|
|
// Convert list to set for fast lookup...
|
|
SmallPtrSet<const MDNode *, 32> OldMDNodeOps;
|
|
for (unsigned i = 0, e = NamedMDOps.size(); i != e; ++i) {
|
|
OldMDNodeOps.insert(NamedMDOps[i]);
|
|
}
|
|
|
|
outs() << "Checking for crash with only " << OldMDNodeOps.size();
|
|
if (OldMDNodeOps.size() == 1)
|
|
outs() << " named metadata operand: ";
|
|
else
|
|
outs() << " named metadata operands: ";
|
|
|
|
ValueToValueMapTy VMap;
|
|
std::unique_ptr<Module> M = CloneModule(BD.getProgram(), VMap);
|
|
|
|
// This is a little wasteful. In the future it might be good if we could have
|
|
// these dropped during cloning.
|
|
for (auto &NamedMD : BD.getProgram().named_metadata()) {
|
|
// Drop the old one and create a new one
|
|
M->eraseNamedMetadata(M->getNamedMetadata(NamedMD.getName()));
|
|
NamedMDNode *NewNamedMDNode =
|
|
M->getOrInsertNamedMetadata(NamedMD.getName());
|
|
for (MDNode *op : NamedMD.operands())
|
|
if (OldMDNodeOps.count(op))
|
|
NewNamedMDNode->addOperand(cast<MDNode>(MapMetadata(op, VMap)));
|
|
}
|
|
|
|
// Verify that this is still valid.
|
|
legacy::PassManager Passes;
|
|
Passes.add(createVerifierPass(/*FatalErrors=*/false));
|
|
Passes.run(*M);
|
|
|
|
// Try running on the hacked up program...
|
|
if (TestFn(BD, M.get())) {
|
|
// Make sure to use instruction pointers that point into the now-current
|
|
// module, and that they don't include any deleted blocks.
|
|
NamedMDOps.clear();
|
|
for (const MDNode *Node : OldMDNodeOps)
|
|
NamedMDOps.push_back(cast<MDNode>(*VMap.getMappedMD(Node)));
|
|
|
|
BD.setNewProgram(std::move(M)); // It crashed, keep the trimmed version...
|
|
return true;
|
|
}
|
|
// It didn't crash, try something else.
|
|
return false;
|
|
}
|
|
|
|
/// Attempt to eliminate as many global initializers as possible.
|
|
static Error ReduceGlobalInitializers(BugDriver &BD, BugTester TestFn) {
|
|
Module &OrigM = BD.getProgram();
|
|
if (OrigM.global_empty())
|
|
return Error::success();
|
|
|
|
// Now try to reduce the number of global variable initializers in the
|
|
// module to something small.
|
|
std::unique_ptr<Module> M = CloneModule(OrigM);
|
|
bool DeletedInit = false;
|
|
|
|
for (GlobalVariable &GV : M->globals()) {
|
|
if (GV.hasInitializer()) {
|
|
DeleteGlobalInitializer(&GV);
|
|
GV.setLinkage(GlobalValue::ExternalLinkage);
|
|
GV.setComdat(nullptr);
|
|
DeletedInit = true;
|
|
}
|
|
}
|
|
|
|
if (!DeletedInit)
|
|
return Error::success();
|
|
|
|
// See if the program still causes a crash...
|
|
outs() << "\nChecking to see if we can delete global inits: ";
|
|
|
|
if (TestFn(BD, M.get())) { // Still crashes?
|
|
BD.setNewProgram(std::move(M));
|
|
outs() << "\n*** Able to remove all global initializers!\n";
|
|
return Error::success();
|
|
}
|
|
|
|
// No longer crashes.
|
|
outs() << " - Removing all global inits hides problem!\n";
|
|
|
|
std::vector<GlobalVariable *> GVs;
|
|
for (GlobalVariable &GV : OrigM.globals())
|
|
if (GV.hasInitializer())
|
|
GVs.push_back(&GV);
|
|
|
|
if (GVs.size() > 1 && !BugpointIsInterrupted) {
|
|
outs() << "\n*** Attempting to reduce the number of global initializers "
|
|
<< "in the testcase\n";
|
|
|
|
unsigned OldSize = GVs.size();
|
|
Expected<bool> Result =
|
|
ReduceCrashingGlobalInitializers(BD, TestFn).reduceList(GVs);
|
|
if (Error E = Result.takeError())
|
|
return E;
|
|
|
|
if (GVs.size() < OldSize)
|
|
BD.EmitProgressBitcode(BD.getProgram(), "reduced-global-variables");
|
|
}
|
|
return Error::success();
|
|
}
|
|
|
|
static Error ReduceInsts(BugDriver &BD, BugTester TestFn) {
|
|
// Attempt to delete instructions using bisection. This should help out nasty
|
|
// cases with large basic blocks where the problem is at one end.
|
|
if (!BugpointIsInterrupted) {
|
|
std::vector<const Instruction *> Insts;
|
|
for (const Function &F : BD.getProgram())
|
|
for (const BasicBlock &BB : F)
|
|
for (const Instruction &I : BB)
|
|
if (!I.isTerminator())
|
|
Insts.push_back(&I);
|
|
|
|
Expected<bool> Result =
|
|
ReduceCrashingInstructions(BD, TestFn).reduceList(Insts);
|
|
if (Error E = Result.takeError())
|
|
return E;
|
|
}
|
|
|
|
unsigned Simplification = 2;
|
|
do {
|
|
if (BugpointIsInterrupted)
|
|
// TODO: Should we distinguish this with an "interrupted error"?
|
|
return Error::success();
|
|
--Simplification;
|
|
outs() << "\n*** Attempting to reduce testcase by deleting instruc"
|
|
<< "tions: Simplification Level #" << Simplification << '\n';
|
|
|
|
// Now that we have deleted the functions that are unnecessary for the
|
|
// program, try to remove instructions that are not necessary to cause the
|
|
// crash. To do this, we loop through all of the instructions in the
|
|
// remaining functions, deleting them (replacing any values produced with
|
|
// nulls), and then running ADCE and SimplifyCFG. If the transformed input
|
|
// still triggers failure, keep deleting until we cannot trigger failure
|
|
// anymore.
|
|
//
|
|
unsigned InstructionsToSkipBeforeDeleting = 0;
|
|
TryAgain:
|
|
|
|
// Loop over all of the (non-terminator) instructions remaining in the
|
|
// function, attempting to delete them.
|
|
unsigned CurInstructionNum = 0;
|
|
for (Module::const_iterator FI = BD.getProgram().begin(),
|
|
E = BD.getProgram().end();
|
|
FI != E; ++FI)
|
|
if (!FI->isDeclaration())
|
|
for (Function::const_iterator BI = FI->begin(), E = FI->end(); BI != E;
|
|
++BI)
|
|
for (BasicBlock::const_iterator I = BI->begin(), E = --BI->end();
|
|
I != E; ++I, ++CurInstructionNum) {
|
|
if (InstructionsToSkipBeforeDeleting) {
|
|
--InstructionsToSkipBeforeDeleting;
|
|
} else {
|
|
if (BugpointIsInterrupted)
|
|
// TODO: Should this be some kind of interrupted error?
|
|
return Error::success();
|
|
|
|
if (I->isEHPad() || I->getType()->isTokenTy() ||
|
|
I->isSwiftError())
|
|
continue;
|
|
|
|
outs() << "Checking instruction: " << *I;
|
|
std::unique_ptr<Module> M =
|
|
BD.deleteInstructionFromProgram(&*I, Simplification);
|
|
|
|
// Find out if the pass still crashes on this pass...
|
|
if (TestFn(BD, M.get())) {
|
|
// Yup, it does, we delete the old module, and continue trying
|
|
// to reduce the testcase...
|
|
BD.setNewProgram(std::move(M));
|
|
InstructionsToSkipBeforeDeleting = CurInstructionNum;
|
|
goto TryAgain; // I wish I had a multi-level break here!
|
|
}
|
|
}
|
|
}
|
|
|
|
if (InstructionsToSkipBeforeDeleting) {
|
|
InstructionsToSkipBeforeDeleting = 0;
|
|
goto TryAgain;
|
|
}
|
|
|
|
} while (Simplification);
|
|
|
|
// Attempt to drop metadata from instructions that does not contribute to the
|
|
// crash.
|
|
if (!BugpointIsInterrupted) {
|
|
std::vector<Instruction *> Insts;
|
|
for (Function &F : BD.getProgram())
|
|
for (Instruction &I : instructions(F))
|
|
Insts.push_back(&I);
|
|
|
|
Expected<bool> Result =
|
|
ReduceCrashingMetadata(BD, TestFn).reduceList(Insts);
|
|
if (Error E = Result.takeError())
|
|
return E;
|
|
}
|
|
|
|
BD.EmitProgressBitcode(BD.getProgram(), "reduced-instructions");
|
|
return Error::success();
|
|
}
|
|
|
|
/// DebugACrash - Given a predicate that determines whether a component crashes
|
|
/// on a program, try to destructively reduce the program while still keeping
|
|
/// the predicate true.
|
|
static Error DebugACrash(BugDriver &BD, BugTester TestFn) {
|
|
// See if we can get away with nuking some of the global variable initializers
|
|
// in the program...
|
|
if (!NoGlobalRM)
|
|
if (Error E = ReduceGlobalInitializers(BD, TestFn))
|
|
return E;
|
|
|
|
// Now try to reduce the number of functions in the module to something small.
|
|
std::vector<Function *> Functions;
|
|
for (Function &F : BD.getProgram())
|
|
if (!F.isDeclaration())
|
|
Functions.push_back(&F);
|
|
|
|
if (Functions.size() > 1 && !BugpointIsInterrupted) {
|
|
outs() << "\n*** Attempting to reduce the number of functions "
|
|
"in the testcase\n";
|
|
|
|
unsigned OldSize = Functions.size();
|
|
Expected<bool> Result =
|
|
ReduceCrashingFunctions(BD, TestFn).reduceList(Functions);
|
|
if (Error E = Result.takeError())
|
|
return E;
|
|
|
|
if (Functions.size() < OldSize)
|
|
BD.EmitProgressBitcode(BD.getProgram(), "reduced-function");
|
|
}
|
|
|
|
if (!NoAttributeRM) {
|
|
// For each remaining function, try to reduce that function's attributes.
|
|
std::vector<std::string> FunctionNames;
|
|
for (Function &F : BD.getProgram())
|
|
FunctionNames.push_back(std::string(F.getName()));
|
|
|
|
if (!FunctionNames.empty() && !BugpointIsInterrupted) {
|
|
outs() << "\n*** Attempting to reduce the number of function attributes"
|
|
" in the testcase\n";
|
|
|
|
unsigned OldSize = 0;
|
|
unsigned NewSize = 0;
|
|
for (std::string &Name : FunctionNames) {
|
|
Function *Fn = BD.getProgram().getFunction(Name);
|
|
assert(Fn && "Could not find function?");
|
|
|
|
std::vector<Attribute> Attrs;
|
|
for (Attribute A : Fn->getAttributes().getFnAttributes())
|
|
Attrs.push_back(A);
|
|
|
|
OldSize += Attrs.size();
|
|
Expected<bool> Result =
|
|
ReduceCrashingFunctionAttributes(BD, Name, TestFn).reduceList(Attrs);
|
|
if (Error E = Result.takeError())
|
|
return E;
|
|
|
|
NewSize += Attrs.size();
|
|
}
|
|
|
|
if (OldSize < NewSize)
|
|
BD.EmitProgressBitcode(BD.getProgram(), "reduced-function-attributes");
|
|
}
|
|
}
|
|
|
|
// Attempt to change conditional branches into unconditional branches to
|
|
// eliminate blocks.
|
|
if (!DisableSimplifyCFG && !BugpointIsInterrupted) {
|
|
std::vector<const BasicBlock *> Blocks;
|
|
for (Function &F : BD.getProgram())
|
|
for (BasicBlock &BB : F)
|
|
Blocks.push_back(&BB);
|
|
unsigned OldSize = Blocks.size();
|
|
Expected<bool> Result =
|
|
ReduceCrashingConditionals(BD, TestFn, true).reduceList(Blocks);
|
|
if (Error E = Result.takeError())
|
|
return E;
|
|
Result = ReduceCrashingConditionals(BD, TestFn, false).reduceList(Blocks);
|
|
if (Error E = Result.takeError())
|
|
return E;
|
|
if (Blocks.size() < OldSize)
|
|
BD.EmitProgressBitcode(BD.getProgram(), "reduced-conditionals");
|
|
}
|
|
|
|
// Attempt to delete entire basic blocks at a time to speed up
|
|
// convergence... this actually works by setting the terminator of the blocks
|
|
// to a return instruction then running simplifycfg, which can potentially
|
|
// shrinks the code dramatically quickly
|
|
//
|
|
if (!DisableSimplifyCFG && !BugpointIsInterrupted) {
|
|
std::vector<const BasicBlock *> Blocks;
|
|
for (Function &F : BD.getProgram())
|
|
for (BasicBlock &BB : F)
|
|
Blocks.push_back(&BB);
|
|
unsigned OldSize = Blocks.size();
|
|
Expected<bool> Result = ReduceCrashingBlocks(BD, TestFn).reduceList(Blocks);
|
|
if (Error E = Result.takeError())
|
|
return E;
|
|
if (Blocks.size() < OldSize)
|
|
BD.EmitProgressBitcode(BD.getProgram(), "reduced-blocks");
|
|
}
|
|
|
|
if (!DisableSimplifyCFG && !BugpointIsInterrupted) {
|
|
std::vector<const BasicBlock *> Blocks;
|
|
for (Function &F : BD.getProgram())
|
|
for (BasicBlock &BB : F)
|
|
Blocks.push_back(&BB);
|
|
unsigned OldSize = Blocks.size();
|
|
Expected<bool> Result = ReduceSimplifyCFG(BD, TestFn).reduceList(Blocks);
|
|
if (Error E = Result.takeError())
|
|
return E;
|
|
if (Blocks.size() < OldSize)
|
|
BD.EmitProgressBitcode(BD.getProgram(), "reduced-simplifycfg");
|
|
}
|
|
|
|
// Attempt to delete instructions using bisection. This should help out nasty
|
|
// cases with large basic blocks where the problem is at one end.
|
|
if (!BugpointIsInterrupted)
|
|
if (Error E = ReduceInsts(BD, TestFn))
|
|
return E;
|
|
|
|
// Attempt to strip debug info metadata.
|
|
auto stripMetadata = [&](std::function<bool(Module &)> strip) {
|
|
std::unique_ptr<Module> M = CloneModule(BD.getProgram());
|
|
strip(*M);
|
|
if (TestFn(BD, M.get()))
|
|
BD.setNewProgram(std::move(M));
|
|
};
|
|
if (!NoStripDebugInfo && !BugpointIsInterrupted) {
|
|
outs() << "\n*** Attempting to strip the debug info: ";
|
|
stripMetadata(StripDebugInfo);
|
|
}
|
|
if (!NoStripDebugTypeInfo && !BugpointIsInterrupted) {
|
|
outs() << "\n*** Attempting to strip the debug type info: ";
|
|
stripMetadata(stripNonLineTableDebugInfo);
|
|
}
|
|
|
|
if (!NoNamedMDRM) {
|
|
if (!BugpointIsInterrupted) {
|
|
// Try to reduce the amount of global metadata (particularly debug info),
|
|
// by dropping global named metadata that anchors them
|
|
outs() << "\n*** Attempting to remove named metadata: ";
|
|
std::vector<std::string> NamedMDNames;
|
|
for (auto &NamedMD : BD.getProgram().named_metadata())
|
|
NamedMDNames.push_back(NamedMD.getName().str());
|
|
Expected<bool> Result =
|
|
ReduceCrashingNamedMD(BD, TestFn).reduceList(NamedMDNames);
|
|
if (Error E = Result.takeError())
|
|
return E;
|
|
}
|
|
|
|
if (!BugpointIsInterrupted) {
|
|
// Now that we quickly dropped all the named metadata that doesn't
|
|
// contribute to the crash, bisect the operands of the remaining ones
|
|
std::vector<const MDNode *> NamedMDOps;
|
|
for (auto &NamedMD : BD.getProgram().named_metadata())
|
|
for (auto op : NamedMD.operands())
|
|
NamedMDOps.push_back(op);
|
|
Expected<bool> Result =
|
|
ReduceCrashingNamedMDOps(BD, TestFn).reduceList(NamedMDOps);
|
|
if (Error E = Result.takeError())
|
|
return E;
|
|
}
|
|
BD.EmitProgressBitcode(BD.getProgram(), "reduced-named-md");
|
|
}
|
|
|
|
// Try to clean up the testcase by running funcresolve and globaldce...
|
|
if (!BugpointIsInterrupted) {
|
|
outs() << "\n*** Attempting to perform final cleanups: ";
|
|
std::unique_ptr<Module> M = CloneModule(BD.getProgram());
|
|
M = BD.performFinalCleanups(std::move(M), true);
|
|
|
|
// Find out if the pass still crashes on the cleaned up program...
|
|
if (M && TestFn(BD, M.get()))
|
|
BD.setNewProgram(
|
|
std::move(M)); // Yup, it does, keep the reduced version...
|
|
}
|
|
|
|
BD.EmitProgressBitcode(BD.getProgram(), "reduced-simplified");
|
|
|
|
return Error::success();
|
|
}
|
|
|
|
static bool TestForOptimizerCrash(const BugDriver &BD, Module *M) {
|
|
return BD.runPasses(*M, BD.getPassesToRun());
|
|
}
|
|
|
|
/// debugOptimizerCrash - This method is called when some pass crashes on input.
|
|
/// It attempts to prune down the testcase to something reasonable, and figure
|
|
/// out exactly which pass is crashing.
|
|
///
|
|
Error BugDriver::debugOptimizerCrash(const std::string &ID) {
|
|
outs() << "\n*** Debugging optimizer crash!\n";
|
|
|
|
// Reduce the list of passes which causes the optimizer to crash...
|
|
if (!BugpointIsInterrupted && !DontReducePassList) {
|
|
Expected<bool> Result = ReducePassList(*this).reduceList(PassesToRun);
|
|
if (Error E = Result.takeError())
|
|
return E;
|
|
}
|
|
|
|
outs() << "\n*** Found crashing pass"
|
|
<< (PassesToRun.size() == 1 ? ": " : "es: ")
|
|
<< getPassesString(PassesToRun) << '\n';
|
|
|
|
EmitProgressBitcode(*Program, ID);
|
|
|
|
auto Res = DebugACrash(*this, TestForOptimizerCrash);
|
|
if (Res || DontReducePassList)
|
|
return Res;
|
|
// Try to reduce the pass list again. This covers additional cases
|
|
// we failed to reduce earlier, because of more complex pass dependencies
|
|
// triggering the crash.
|
|
auto SecondRes = ReducePassList(*this).reduceList(PassesToRun);
|
|
if (Error E = SecondRes.takeError())
|
|
return E;
|
|
outs() << "\n*** Found crashing pass"
|
|
<< (PassesToRun.size() == 1 ? ": " : "es: ")
|
|
<< getPassesString(PassesToRun) << '\n';
|
|
|
|
EmitProgressBitcode(getProgram(), "reduced-simplified");
|
|
return Res;
|
|
}
|
|
|
|
static bool TestForCodeGenCrash(const BugDriver &BD, Module *M) {
|
|
if (Error E = BD.compileProgram(*M)) {
|
|
if (VerboseErrors)
|
|
errs() << toString(std::move(E)) << "\n";
|
|
else {
|
|
consumeError(std::move(E));
|
|
errs() << "<crash>\n";
|
|
}
|
|
return true; // Tool is still crashing.
|
|
}
|
|
errs() << '\n';
|
|
return false;
|
|
}
|
|
|
|
/// debugCodeGeneratorCrash - This method is called when the code generator
|
|
/// crashes on an input. It attempts to reduce the input as much as possible
|
|
/// while still causing the code generator to crash.
|
|
Error BugDriver::debugCodeGeneratorCrash() {
|
|
errs() << "*** Debugging code generator crash!\n";
|
|
|
|
return DebugACrash(*this, TestForCodeGenCrash);
|
|
}
|