/// ExtractBlocks - Given a reduced list of functions that still expose the bug,
/// extract as many basic blocks from the region as possible without obscuring
/// the bug.
///
static bool ExtractBlocks(BugDriver &BD,
bool (*TestFn)(BugDriver &, Module *, Module *,
std::string &),
std::vector<Function*> &MiscompiledFunctions,
std::string &Error) {
if (BugpointIsInterrupted) return false;
std::vector<BasicBlock*> Blocks;
for (unsigned i = 0, e = MiscompiledFunctions.size(); i != e; ++i)
for (BasicBlock &BB : *MiscompiledFunctions[i])
Blocks.push_back(&BB);
// Use the list reducer to identify blocks that can be extracted without
// obscuring the bug. The Blocks list will end up containing blocks that must
// be retained from the original program.
unsigned OldSize = Blocks.size();
// Check to see if all blocks are extractible first.
bool Ret = ReduceMiscompiledBlocks(BD, TestFn, MiscompiledFunctions)
.TestFuncs(std::vector<BasicBlock*>(), Error);
if (!Error.empty())
return false;
if (Ret) {
Blocks.clear();
} else {
ReduceMiscompiledBlocks(BD, TestFn,
MiscompiledFunctions).reduceList(Blocks, Error);
if (!Error.empty())
return false;
if (Blocks.size() == OldSize)
return false;
}
ValueToValueMapTy VMap;
Module *ProgClone = CloneModule(BD.getProgram(), VMap);
Module *ToExtract = SplitFunctionsOutOfModule(ProgClone,
MiscompiledFunctions,
VMap);
std::unique_ptr<Module> Extracted =
BD.extractMappedBlocksFromModule(Blocks, ToExtract);
if (!Extracted) {
// Weird, extraction should have worked.
errs() << "Nondeterministic problem extracting blocks??\n";
delete ProgClone;
delete ToExtract;
return false;
}
// Otherwise, block extraction succeeded. Link the two program fragments back
// together.
delete ToExtract;
std::vector<std::pair<std::string, FunctionType*> > MisCompFunctions;
for (Module::iterator I = Extracted->begin(), E = Extracted->end();
I != E; ++I)
if (!I->isDeclaration())
MisCompFunctions.emplace_back(I->getName(), I->getFunctionType());
if (Linker::linkModules(*ProgClone, *Extracted, diagnosticHandler))
exit(1);
// Set the new program and delete the old one.
BD.setNewProgram(ProgClone);
// Update the list of miscompiled functions.
MiscompiledFunctions.clear();
for (unsigned i = 0, e = MisCompFunctions.size(); i != e; ++i) {
Function *NewF = ProgClone->getFunction(MisCompFunctions[i].first);
assert(NewF && "Function not found??");
MiscompiledFunctions.push_back(NewF);
}
return true;
}
