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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 "Searcher.h"
#include "Executor.h"
#include "klee/Internal/Support/ErrorHandling.h"
#include "llvm/Support/CommandLine.h"
using namespace llvm;
using namespace klee;
namespace {
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 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"),
clEnumValEnd));
cl::opt<bool>
UseIterativeDeepeningTimeSearch("use-iterative-deepening-time-search",
cl::desc("(experimental)"));
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)"),
cl::init(false));
cl::opt<unsigned>
BatchInstructions("batch-instructions",
cl::desc("Number of instructions to batch when using --use-batching-search"),
cl::init(10000));
cl::opt<double>
BatchTime("batch-time",
cl::desc("Amount of time to batch when using --use-batching-search"),
cl::init(5.0));
cl::opt<bool>
UseMerge("use-merge",
cl::desc("Enable support for klee_merge() (experimental)"));
cl::opt<bool>
UseBumpMerge("use-bump-merge",
cl::desc("Enable support for klee_merge() (extra experimental)"));
}
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, Executor &executor) {
Searcher *searcher = NULL;
switch (type) {
case Searcher::DFS: searcher = new DFSSearcher(); break;
case Searcher::BFS: searcher = new BFSSearcher(); break;
case Searcher::RandomState: searcher = new RandomSearcher(); break;
case Searcher::RandomPath: searcher = new RandomPathSearcher(executor); break;
case Searcher::NURS_CovNew: searcher = new WeightedRandomSearcher(WeightedRandomSearcher::CoveringNew); break;
case Searcher::NURS_MD2U: searcher = new WeightedRandomSearcher(WeightedRandomSearcher::MinDistToUncovered); break;
case Searcher::NURS_Depth: searcher = new WeightedRandomSearcher(WeightedRandomSearcher::Depth); break;
case Searcher::NURS_ICnt: searcher = new WeightedRandomSearcher(WeightedRandomSearcher::InstCount); break;
case Searcher::NURS_CPICnt: searcher = new WeightedRandomSearcher(WeightedRandomSearcher::CPInstCount); break;
case Searcher::NURS_QC: searcher = new WeightedRandomSearcher(WeightedRandomSearcher::QueryCost); break;
}
return searcher;
}
Searcher *klee::constructUserSearcher(Executor &executor) {
// default values
if (CoreSearch.size() == 0) {
CoreSearch.push_back(Searcher::RandomPath);
CoreSearch.push_back(Searcher::NURS_CovNew);
}
Searcher *searcher = getNewSearcher(CoreSearch[0], executor);
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));
searcher = new InterleavedSearcher(s);
}
if (UseBatchingSearch) {
searcher = new BatchingSearcher(searcher, BatchTime, BatchInstructions);
}
// merge support is experimental
if (UseMerge) {
if (UseBumpMerge)
klee_error("use-merge and use-bump-merge cannot be used together");
// RandomPathSearcher cannot be used in conjunction with MergingSearcher,
// see MergingSearcher::selectState() for explanation.
if (std::find(CoreSearch.begin(), CoreSearch.end(), Searcher::RandomPath) != CoreSearch.end())
klee_error("use-merge currently does not support random-path, please use another search strategy");
searcher = new MergingSearcher(executor, searcher);
} else if (UseBumpMerge) {
searcher = new BumpMergingSearcher(executor, searcher);
}
if (UseIterativeDeepeningTimeSearch) {
searcher = new IterativeDeepeningTimeSearcher(searcher);
}
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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