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//===-- UserSearcher.cpp --------------------------------------------------===//
//
// The KLEE Symbolic Virtual Machine
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "UserSearcher.h"
#include "Executor.h"
#include "MergeHandler.h"
#include "Searcher.h"
#include "klee/Support/ErrorHandling.h"
#include "llvm/Support/CommandLine.h"
using namespace llvm;
using namespace klee;
namespace {
llvm::cl::OptionCategory
SearchCat("Search options", "These options control the search heuristic.");
cl::list<Searcher::CoreSearchType> CoreSearch(
"search",
cl::desc("Specify the search heuristic (default=random-path interleaved "
"with nurs:covnew)"),
cl::values(
clEnumValN(Searcher::DFS, "dfs", "use Depth First Search (DFS)"),
clEnumValN(Searcher::BFS, "bfs",
"use Breadth First Search (BFS), where scheduling decisions "
"are taken at the level of (2-way) forks"),
clEnumValN(Searcher::RandomState, "random-state",
"randomly select a state to explore"),
clEnumValN(Searcher::RandomPath, "random-path",
"use Random Path Selection (see OSDI'08 paper)"),
clEnumValN(Searcher::NURS_CovNew, "nurs:covnew",
"use Non Uniform Random Search (NURS) with Coverage-New"),
clEnumValN(Searcher::NURS_MD2U, "nurs:md2u",
"use NURS with Min-Dist-to-Uncovered"),
clEnumValN(Searcher::NURS_Depth, "nurs:depth", "use NURS with depth"),
clEnumValN(Searcher::NURS_RP, "nurs:rp", "use NURS with 1/2^depth"),
clEnumValN(Searcher::NURS_ICnt, "nurs:icnt",
"use NURS with Instr-Count"),
clEnumValN(Searcher::NURS_CPICnt, "nurs:cpicnt",
"use NURS with CallPath-Instr-Count"),
clEnumValN(Searcher::NURS_QC, "nurs:qc", "use NURS with Query-Cost")),
cl::cat(SearchCat));
cl::opt<bool> UseIterativeDeepeningTimeSearch(
"use-iterative-deepening-time-search",
cl::desc(
"Use iterative deepening time search (experimental) (default=false)"),
cl::init(false),
cl::cat(SearchCat));
cl::opt<bool> UseBatchingSearch(
"use-batching-search",
cl::desc("Use batching searcher (keep running selected state for N "
"instructions/time, see --batch-instructions and --batch-time) "
"(default=false)"),
cl::init(false),
cl::cat(SearchCat));
cl::opt<unsigned> BatchInstructions(
"batch-instructions",
cl::desc("Number of instructions to batch when using "
"--use-batching-search. Set to 0 to disable (default=10000)"),
cl::init(10000),
cl::cat(SearchCat));
cl::opt<std::string> BatchTime(
"batch-time",
cl::desc("Amount of time to batch when using "
"--use-batching-search. Set to 0s to disable (default=5s)"),
cl::init("5s"),
cl::cat(SearchCat));
} // namespace
void klee::initializeSearchOptions() {
// default values
if (CoreSearch.empty()) {
if (UseMerge){
CoreSearch.push_back(Searcher::NURS_CovNew);
klee_warning("--use-merge enabled. Using NURS_CovNew as default searcher.");
} else {
CoreSearch.push_back(Searcher::RandomPath);
CoreSearch.push_back(Searcher::NURS_CovNew);
}
}
}
bool klee::userSearcherRequiresMD2U() {
return (std::find(CoreSearch.begin(), CoreSearch.end(), Searcher::NURS_MD2U) != CoreSearch.end() ||
std::find(CoreSearch.begin(), CoreSearch.end(), Searcher::NURS_CovNew) != CoreSearch.end() ||
std::find(CoreSearch.begin(), CoreSearch.end(), Searcher::NURS_ICnt) != CoreSearch.end() ||
std::find(CoreSearch.begin(), CoreSearch.end(), Searcher::NURS_CPICnt) != CoreSearch.end() ||
std::find(CoreSearch.begin(), CoreSearch.end(), Searcher::NURS_QC) != CoreSearch.end());
}
Searcher *getNewSearcher(Searcher::CoreSearchType type, RNG &rng, PTree &processTree) {
Searcher *searcher = nullptr;
switch (type) {
case Searcher::DFS: searcher = new DFSSearcher(); break;
case Searcher::BFS: searcher = new BFSSearcher(); break;
case Searcher::RandomState: searcher = new RandomSearcher(rng); break;
case Searcher::RandomPath: searcher = new RandomPathSearcher(processTree, rng); break;
case Searcher::NURS_CovNew: searcher = new WeightedRandomSearcher(WeightedRandomSearcher::CoveringNew, rng); break;
case Searcher::NURS_MD2U: searcher = new WeightedRandomSearcher(WeightedRandomSearcher::MinDistToUncovered, rng); break;
case Searcher::NURS_Depth: searcher = new WeightedRandomSearcher(WeightedRandomSearcher::Depth, rng); break;
case Searcher::NURS_RP: searcher = new WeightedRandomSearcher(WeightedRandomSearcher::RP, rng); break;
case Searcher::NURS_ICnt: searcher = new WeightedRandomSearcher(WeightedRandomSearcher::InstCount, rng); break;
case Searcher::NURS_CPICnt: searcher = new WeightedRandomSearcher(WeightedRandomSearcher::CPInstCount, rng); break;
case Searcher::NURS_QC: searcher = new WeightedRandomSearcher(WeightedRandomSearcher::QueryCost, rng); break;
}
return searcher;
}
Searcher *klee::constructUserSearcher(Executor &executor) {
Searcher *searcher = getNewSearcher(CoreSearch[0], executor.theRNG, *executor.processTree);
if (CoreSearch.size() > 1) {
std::vector<Searcher *> s;
s.push_back(searcher);
for (unsigned i = 1; i < CoreSearch.size(); i++)
s.push_back(getNewSearcher(CoreSearch[i], executor.theRNG, *executor.processTree));
searcher = new InterleavedSearcher(s);
}
if (UseBatchingSearch) {
searcher = new BatchingSearcher(searcher, time::Span(BatchTime),
BatchInstructions);
}
if (UseIterativeDeepeningTimeSearch) {
searcher = new IterativeDeepeningTimeSearcher(searcher);
}
if (UseMerge) {
auto *ms = new MergingSearcher(searcher);
executor.setMergingSearcher(ms);
searcher = ms;
}
llvm::raw_ostream &os = executor.getHandler().getInfoStream();
os << "BEGIN searcher description\n";
searcher->printName(os);
os << "END searcher description\n";
return searcher;
}
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