intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

3 files changed, 1096 insertions, 0 deletions

diff --git a/contrib/libs/hyperscan/src/smallwrite/smallwrite_build.cpp b/contrib/libs/hyperscan/src/smallwrite/smallwrite_build.cpp
new file mode 100644
index 0000000000..d993137632
--- /dev/null
+++ b/contrib/libs/hyperscan/src/smallwrite/smallwrite_build.cpp
@@ -0,0 +1,963 @@
+/*
+ * Copyright (c) 2015-2020, Intel Corporation
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *  * Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *  * Neither the name of Intel Corporation nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/**
+ * \file
+ * \brief Small-write engine build code.
+ */
+
+#include "smallwrite/smallwrite_build.h"
+
+#include "grey.h"
+#include "ue2common.h"
+#include "compiler/compiler.h"
+#include "nfa/dfa_min.h"
+#include "nfa/mcclellancompile.h"
+#include "nfa/mcclellancompile_util.h"
+#include "nfa/nfa_internal.h"
+#include "nfa/rdfa_merge.h"
+#include "nfa/shengcompile.h"
+#include "nfagraph/ng.h"
+#include "nfagraph/ng_depth.h"
+#include "nfagraph/ng_holder.h"
+#include "nfagraph/ng_mcclellan.h"
+#include "nfagraph/ng_reports.h"
+#include "nfagraph/ng_prune.h"
+#include "nfagraph/ng_util.h"
+#include "smallwrite/smallwrite_internal.h"
+#include "util/alloc.h"
+#include "util/bytecode_ptr.h"
+#include "util/charreach.h"
+#include "util/compare.h"
+#include "util/compile_context.h"
+#include "util/container.h"
+#include "util/make_unique.h"
+#include "util/ue2_graph.h"
+#include "util/ue2string.h"
+#include "util/verify_types.h"
+
+#include <map>
+#include <set>
+#include <vector>
+#include <utility>
+
+#include <boost/graph/breadth_first_search.hpp>
+
+using namespace std;
+
+namespace ue2 {
+
+#define DFA_MERGE_MAX_STATES 8000
+#define MAX_TRIE_VERTICES 8000
+
+struct LitTrieVertexProps {
+    LitTrieVertexProps() = default;
+    explicit LitTrieVertexProps(u8 c_in) : c(c_in) {}
+    size_t index; // managed by ue2_graph
+    u8 c = 0; //!< character reached on this vertex
+    flat_set<ReportID> reports; //!< managed reports fired on this vertex
+};
+
+struct LitTrieEdgeProps {
+    size_t index; // managed by ue2_graph
+};
+
+/**
+ * \brief BGL graph used to store a trie of literals (for later AC construction
+ * into a DFA).
+ */
+struct LitTrie
+    : public ue2_graph<LitTrie, LitTrieVertexProps, LitTrieEdgeProps> {
+
+    LitTrie() : root(add_vertex(*this)) {}
+
+    const vertex_descriptor root; //!< Root vertex for the trie.
+};
+
+static
+bool is_empty(const LitTrie &trie) {
+    return num_vertices(trie) <= 1;
+}
+
+static
+std::set<ReportID> all_reports(const LitTrie &trie) {
+    std::set<ReportID> reports;
+    for (auto v : vertices_range(trie)) {
+        insert(&reports, trie[v].reports);
+    }
+    return reports;
+}
+
+using LitTrieVertex = LitTrie::vertex_descriptor;
+using LitTrieEdge = LitTrie::edge_descriptor;
+
+namespace { // unnamed
+
+// Concrete impl class
+class SmallWriteBuildImpl : public SmallWriteBuild {
+public:
+    SmallWriteBuildImpl(size_t num_patterns, const ReportManager &rm,
+                        const CompileContext &cc);
+
+    // Construct a runtime implementation.
+    bytecode_ptr<SmallWriteEngine> build(u32 roseQuality) override;
+
+    void add(const NGHolder &g, const ExpressionInfo &expr) override;
+    void add(const ue2_literal &literal, ReportID r) override;
+
+    set<ReportID> all_reports() const override;
+
+    const ReportManager &rm;
+    const CompileContext &cc;
+
+    vector<unique_ptr<raw_dfa>> dfas;
+    LitTrie lit_trie;
+    LitTrie lit_trie_nocase;
+    size_t num_literals = 0;
+    bool poisoned;
+};
+
+} // namespace
+
+SmallWriteBuild::~SmallWriteBuild() = default;
+
+SmallWriteBuildImpl::SmallWriteBuildImpl(size_t num_patterns,
+                                         const ReportManager &rm_in,
+                                         const CompileContext &cc_in)
+    : rm(rm_in), cc(cc_in),
+      /* small write is block mode only */
+      poisoned(!cc.grey.allowSmallWrite
+               || cc.streaming
+               || num_patterns > cc.grey.smallWriteMaxPatterns) {
+}
+
+/**
+ * \brief Remove any reports from the given vertex that cannot match within
+ * max_depth due to their constraints.
+ */
+static
+bool pruneOverlongReports(NFAVertex v, NGHolder &g, const depth &max_depth,
+                          const ReportManager &rm) {
+    assert(!g[v].reports.empty());
+
+    vector<ReportID> bad_reports;
+
+    for (ReportID id : g[v].reports) {
+        const auto &report = rm.getReport(id);
+        if (report.minOffset > max_depth) {
+            bad_reports.push_back(id);
+        }
+    }
+
+    for (ReportID id : bad_reports) {
+        g[v].reports.erase(id);
+    }
+
+    if (g[v].reports.empty()) {
+        DEBUG_PRINTF("none of vertex %zu's reports can match, cut accepts\n",
+                     g[v].index);
+        remove_edge(v, g.accept, g);
+        remove_edge(v, g.acceptEod, g);
+    }
+
+    return !bad_reports.empty();
+}
+
+/**
+ * \brief Prune vertices and reports from the graph that cannot match within
+ * max_depth.
+ */
+static
+bool pruneOverlong(NGHolder &g, const depth &max_depth,
+                   const ReportManager &rm) {
+    bool modified = false;
+    auto depths = calcBidiDepths(g);
+
+    for (auto v : vertices_range(g)) {
+        if (is_special(v, g)) {
+            continue;
+        }
+        const auto &d = depths.at(g[v].index);
+        depth min_match_offset = min(d.fromStart.min, d.fromStartDotStar.min)
+                               + min(d.toAccept.min, d.toAcceptEod.min);
+        if (min_match_offset > max_depth) {
+            clear_vertex(v, g);
+            modified = true;
+            continue;
+        }
+
+        if (is_match_vertex(v, g)) {
+            modified |= pruneOverlongReports(v, g, max_depth, rm);
+        }
+    }
+
+    if (modified) {
+        pruneUseless(g);
+        DEBUG_PRINTF("pruned graph down to %zu vertices\n", num_vertices(g));
+    }
+
+    return modified;
+}
+
+/**
+ * \brief Attempt to merge the set of DFAs given down into a single raw_dfa.
+ * Returns false on failure.
+ */
+static
+bool mergeDfas(vector<unique_ptr<raw_dfa>> &dfas, const ReportManager &rm,
+               const CompileContext &cc) {
+    assert(!dfas.empty());
+
+    if (dfas.size() == 1) {
+        return true;
+    }
+
+    DEBUG_PRINTF("attempting to merge %zu DFAs\n", dfas.size());
+
+    vector<const raw_dfa *> dfa_ptrs;
+    dfa_ptrs.reserve(dfas.size());
+    for (auto &d : dfas) {
+        dfa_ptrs.push_back(d.get());
+    }
+
+    auto merged = mergeAllDfas(dfa_ptrs, DFA_MERGE_MAX_STATES, &rm, cc.grey);
+    if (!merged) {
+        DEBUG_PRINTF("merge failed\n");
+        return false;
+    }
+
+    DEBUG_PRINTF("merge succeeded, result has %zu states\n",
+                  merged->states.size());
+    dfas.clear();
+    dfas.push_back(std::move(merged));
+    return true;
+}
+
+void SmallWriteBuildImpl::add(const NGHolder &g, const ExpressionInfo &expr) {
+    // If the graph is poisoned (i.e. we can't build a SmallWrite version),
+    // we don't even try.
+    if (poisoned) {
+        return;
+    }
+
+    if (expr.som) {
+        DEBUG_PRINTF("no SOM support in small-write engine\n");
+        poisoned = true;
+        return;
+    }
+
+    if (isVacuous(g)) {
+        DEBUG_PRINTF("no vacuous graph support in small-write engine\n");
+        poisoned = true;
+        return;
+    }
+
+    if (any_of_in(::ue2::all_reports(g), [&](ReportID id) {
+            return rm.getReport(id).minLength > 0;
+        })) {
+        DEBUG_PRINTF("no min_length extparam support in small-write engine\n");
+        poisoned = true;
+        return;
+    }
+
+    DEBUG_PRINTF("g=%p\n", &g);
+
+    // make a copy of the graph so that we can modify it for our purposes
+    unique_ptr<NGHolder> h = cloneHolder(g);
+
+    pruneOverlong(*h, depth(cc.grey.smallWriteLargestBuffer), rm);
+
+    reduceGraph(*h, SOM_NONE, expr.utf8, cc);
+
+    if (can_never_match(*h)) {
+        DEBUG_PRINTF("graph can never match in small block\n");
+        return;
+    }
+
+    // Now we can actually build the McClellan DFA
+    assert(h->kind == NFA_OUTFIX);
+    auto r = buildMcClellan(*h, &rm, cc.grey);
+
+    // If we couldn't build a McClellan DFA for this portion, we won't be able
+    // build a smwr which represents the pattern set
+    if (!r) {
+        DEBUG_PRINTF("failed to determinise\n");
+        poisoned = true;
+        return;
+    }
+
+    if (clear_deeper_reports(*r, cc.grey.smallWriteLargestBuffer)) {
+        minimize_hopcroft(*r, cc.grey);
+    }
+
+    dfas.push_back(std::move(r));
+
+    if (dfas.size() >= cc.grey.smallWriteMergeBatchSize) {
+        if (!mergeDfas(dfas, rm, cc)) {
+            dfas.clear();
+            poisoned = true;
+            return;
+        }
+    }
+}
+
+static
+bool add_to_trie(const ue2_literal &literal, ReportID report, LitTrie &trie) {
+    auto u = trie.root;
+    for (const auto &c : literal) {
+        auto next = LitTrie::null_vertex();
+        for (auto v : adjacent_vertices_range(u, trie)) {
+            if (trie[v].c == (u8)c.c) {
+                next = v;
+                break;
+            }
+        }
+        if (!next) {
+            next = add_vertex(LitTrieVertexProps((u8)c.c), trie);
+            add_edge(u, next, trie);
+        }
+        u = next;
+    }
+
+    trie[u].reports.insert(report);
+
+    DEBUG_PRINTF("added '%s' (report %u) to trie, now %zu vertices\n",
+                  escapeString(literal).c_str(), report, num_vertices(trie));
+    return num_vertices(trie) <= MAX_TRIE_VERTICES;
+}
+
+void SmallWriteBuildImpl::add(const ue2_literal &literal, ReportID r) {
+    // If the graph is poisoned (i.e. we can't build a SmallWrite version),
+    // we don't even try.
+    if (poisoned) {
+        DEBUG_PRINTF("poisoned\n");
+        return;
+    }
+
+    if (literal.length() > cc.grey.smallWriteLargestBuffer) {
+        DEBUG_PRINTF("exceeded length limit\n");
+        return; /* too long */
+    }
+
+    if (++num_literals > cc.grey.smallWriteMaxLiterals) {
+        DEBUG_PRINTF("exceeded literal limit\n");
+        poisoned = true;
+        return;
+    }
+
+    auto &trie = literal.any_nocase() ? lit_trie_nocase : lit_trie;
+    if (!add_to_trie(literal, r, trie)) {
+        DEBUG_PRINTF("trie add failed\n");
+        poisoned = true;
+    }
+}
+
+namespace {
+
+/**
+ * \brief BFS visitor for Aho-Corasick automaton construction.
+ *
+ * This is doing two things:
+ *
+ *   - Computing the failure edges (also called fall or supply edges) for each
+ *     vertex, giving the longest suffix of the path to that point that is also
+ *     a prefix in the trie reached on the same character. The BFS traversal
+ *     makes it possible to build these from earlier failure paths.
+ *
+ *   - Computing the output function for each vertex, which is done by
+ *     propagating the reports from failure paths as well. This ensures that
+ *     substrings of the current path also report correctly.
+ */
+struct ACVisitor : public boost::default_bfs_visitor {
+    ACVisitor(LitTrie &trie_in,
+              unordered_map<LitTrieVertex, LitTrieVertex> &failure_map_in,
+              vector<LitTrieVertex> &ordering_in)
+        : mutable_trie(trie_in), failure_map(failure_map_in),
+          ordering(ordering_in) {}
+
+    LitTrieVertex find_failure_target(LitTrieVertex u, LitTrieVertex v,
+                                      const LitTrie &trie) {
+        assert(u == trie.root || contains(failure_map, u));
+        assert(!contains(failure_map, v));
+
+        const auto &c = trie[v].c;
+
+        while (u != trie.root) {
+            auto f = failure_map.at(u);
+            for (auto w : adjacent_vertices_range(f, trie)) {
+                if (trie[w].c == c) {
+                    return w;
+                }
+            }
+            u = f;
+        }
+
+        DEBUG_PRINTF("no failure edge\n");
+        return LitTrie::null_vertex();
+    }
+
+    void tree_edge(LitTrieEdge e, const LitTrie &trie) {
+        auto u = source(e, trie);
+        auto v = target(e, trie);
+        DEBUG_PRINTF("bfs (%zu, %zu) on '%c'\n", trie[u].index, trie[v].index,
+                     trie[v].c);
+        ordering.push_back(v);
+
+        auto f = find_failure_target(u, v, trie);
+
+        if (f) {
+            DEBUG_PRINTF("final failure vertex %zu\n", trie[f].index);
+            failure_map.emplace(v, f);
+
+            // Propagate reports from failure path to ensure we correctly
+            // report substrings.
+            insert(&mutable_trie[v].reports, mutable_trie[f].reports);
+        } else {
+            DEBUG_PRINTF("final failure vertex root\n");
+            failure_map.emplace(v, trie.root);
+        }
+    }
+
+private:
+    LitTrie &mutable_trie; //!< For setting reports property.
+    unordered_map<LitTrieVertex, LitTrieVertex> &failure_map;
+    vector<LitTrieVertex> &ordering; //!< BFS ordering for vertices.
+};
+}
+
+static UNUSED
+bool isSaneTrie(const LitTrie &trie) {
+    CharReach seen;
+    for (auto u : vertices_range(trie)) {
+        seen.clear();
+        for (auto v : adjacent_vertices_range(u, trie)) {
+            if (seen.test(trie[v].c)) {
+                return false;
+            }
+            seen.set(trie[v].c);
+        }
+    }
+    return true;
+}
+
+/**
+ * \brief Turn the given literal trie into an AC automaton by adding additional
+ * edges and reports.
+ */
+static
+void buildAutomaton(LitTrie &trie,
+                    unordered_map<LitTrieVertex, LitTrieVertex> &failure_map,
+                    vector<LitTrieVertex> &ordering) {
+    assert(isSaneTrie(trie));
+
+    // Find our failure transitions and reports.
+    failure_map.reserve(num_vertices(trie));
+    ordering.reserve(num_vertices(trie));
+    ACVisitor ac_vis(trie, failure_map, ordering);
+    boost::breadth_first_search(trie, trie.root, visitor(ac_vis));
+
+    // Compute missing edges from failure map.
+    for (auto v : ordering) {
+        DEBUG_PRINTF("vertex %zu\n", trie[v].index);
+        CharReach seen;
+        for (auto w : adjacent_vertices_range(v, trie)) {
+            DEBUG_PRINTF("edge to %zu with reach 0x%02x\n", trie[w].index,
+                         trie[w].c);
+            assert(!seen.test(trie[w].c));
+            seen.set(trie[w].c);
+        }
+        auto parent = failure_map.at(v);
+        for (auto w : adjacent_vertices_range(parent, trie)) {
+            if (!seen.test(trie[w].c)) {
+                add_edge(v, w, trie);
+            }
+        }
+    }
+}
+
+static
+vector<u32> findDistFromRoot(const LitTrie &trie) {
+    vector<u32> dist(num_vertices(trie), UINT32_MAX);
+    dist[trie[trie.root].index] = 0;
+
+    // BFS to find dist from root.
+    breadth_first_search(
+        trie, trie.root,
+        visitor(make_bfs_visitor(record_distances(
+            make_iterator_property_map(dist.begin(),
+                                       get(&LitTrieVertexProps::index, trie)),
+            boost::on_tree_edge()))));
+
+    return dist;
+}
+
+static
+vector<u32> findDistToAccept(const LitTrie &trie) {
+    vector<u32> dist(num_vertices(trie), UINT32_MAX);
+
+    // Start with all reporting vertices.
+    deque<LitTrieVertex> q;
+    for (auto v : vertices_range(trie)) {
+        if (!trie[v].reports.empty()) {
+            q.push_back(v);
+            dist[trie[v].index] = 0;
+        }
+    }
+
+    // Custom BFS, since we have a pile of sources.
+    while (!q.empty()) {
+        auto v = q.front();
+        q.pop_front();
+        u32 d = dist[trie[v].index];
+
+        for (auto u : inv_adjacent_vertices_range(v, trie)) {
+            auto &u_dist = dist[trie[u].index];
+            if (u_dist == UINT32_MAX) {
+                q.push_back(u);
+                u_dist = d + 1;
+            }
+        }
+    }
+
+    return dist;
+}
+
+/**
+ * \brief Prune all vertices from the trie that do not lie on a path from root
+ * to accept of length <= max_depth.
+ */
+static
+void pruneTrie(LitTrie &trie, u32 max_depth) {
+    DEBUG_PRINTF("pruning trie to %u\n", max_depth);
+
+    auto dist_from_root = findDistFromRoot(trie);
+    auto dist_to_accept = findDistToAccept(trie);
+
+    vector<LitTrieVertex> dead;
+    for (auto v : vertices_range(trie)) {
+        if (v == trie.root) {
+            continue;
+        }
+        auto v_index = trie[v].index;
+        DEBUG_PRINTF("vertex %zu: from_start=%u, to_accept=%u\n", trie[v].index,
+                     dist_from_root[v_index], dist_to_accept[v_index]);
+        assert(dist_from_root[v_index] != UINT32_MAX);
+        assert(dist_to_accept[v_index] != UINT32_MAX);
+        u32 min_path_len = dist_from_root[v_index] + dist_to_accept[v_index];
+        if (min_path_len > max_depth) {
+            DEBUG_PRINTF("pruning vertex %zu (min path len %u)\n",
+                         trie[v].index, min_path_len);
+            clear_vertex(v, trie);
+            dead.push_back(v);
+        }
+    }
+
+    if (dead.empty()) {
+        return;
+    }
+
+    for (auto v : dead) {
+        remove_vertex(v, trie);
+    }
+
+    DEBUG_PRINTF("%zu vertices remain\n", num_vertices(trie));
+
+    renumber_edges(trie);
+    renumber_vertices(trie);
+}
+
+static
+vector<CharReach> getAlphabet(const LitTrie &trie, bool nocase) {
+    vector<CharReach> esets = {CharReach::dot()};
+    for (auto v : vertices_range(trie)) {
+        if (v == trie.root) {
+            continue;
+        }
+
+        CharReach cr;
+        if (nocase) {
+            cr.set(mytoupper(trie[v].c));
+            cr.set(mytolower(trie[v].c));
+        } else {
+            cr.set(trie[v].c);
+        }
+
+        for (size_t i = 0; i < esets.size(); i++) {
+            if (esets[i].count() == 1) {
+                continue;
+            }
+
+            CharReach t = cr & esets[i];
+            if (t.any() && t != esets[i]) {
+                esets[i] &= ~t;
+                esets.push_back(t);
+            }
+        }
+    }
+
+    // For deterministic compiles.
+    sort(esets.begin(), esets.end());
+    return esets;
+}
+
+static
+u16 buildAlphabet(const LitTrie &trie, bool nocase,
+                  array<u16, ALPHABET_SIZE> &alpha,
+                  array<u16, ALPHABET_SIZE> &unalpha) {
+    const auto &esets = getAlphabet(trie, nocase);
+
+    u16 i = 0;
+    for (const auto &cr : esets) {
+        u16 leader = cr.find_first();
+        for (size_t s = cr.find_first(); s != cr.npos; s = cr.find_next(s)) {
+            alpha[s] = i;
+        }
+        unalpha[i] = leader;
+        i++;
+    }
+
+    for (u16 j = N_CHARS; j < ALPHABET_SIZE; j++, i++) {
+        alpha[j] = i;
+        unalpha[i] = j;
+    }
+
+    DEBUG_PRINTF("alphabet size %u\n", i);
+    return i;
+}
+
+/**
+ * \brief Calculate state mapping, from vertex in trie to state index in BFS
+ * ordering.
+ */
+static
+unordered_map<LitTrieVertex, u32>
+makeStateMap(const LitTrie &trie, const vector<LitTrieVertex> &ordering) {
+    unordered_map<LitTrieVertex, u32> state_ids;
+    state_ids.reserve(num_vertices(trie));
+    u32 idx = DEAD_STATE + 1;
+    state_ids.emplace(trie.root, idx++);
+    for (auto v : ordering) {
+        state_ids.emplace(v, idx++);
+    }
+    assert(state_ids.size() == num_vertices(trie));
+    return state_ids;
+}
+
+/** \brief Construct a raw_dfa from a literal trie. */
+static
+unique_ptr<raw_dfa> buildDfa(LitTrie &trie, bool nocase) {
+    DEBUG_PRINTF("trie has %zu states\n", num_vertices(trie));
+
+    vector<LitTrieVertex> ordering;
+    unordered_map<LitTrieVertex, LitTrieVertex> failure_map;
+    buildAutomaton(trie, failure_map, ordering);
+
+    // Construct DFA states in BFS order.
+    const auto state_ids = makeStateMap(trie, ordering);
+
+    auto rdfa = std::make_unique<raw_dfa>(NFA_OUTFIX);
+
+    // Calculate alphabet.
+    array<u16, ALPHABET_SIZE> unalpha;
+    auto &alpha = rdfa->alpha_remap;
+    rdfa->alpha_size = buildAlphabet(trie, nocase, alpha, unalpha);
+
+    // Construct states and transitions.
+    const u16 root_state = state_ids.at(trie.root);
+    assert(root_state == DEAD_STATE + 1);
+    rdfa->start_anchored = root_state;
+    rdfa->start_floating = root_state;
+    rdfa->states.resize(num_vertices(trie) + 1, dstate(rdfa->alpha_size));
+
+    // Dead state.
+    fill(rdfa->states[DEAD_STATE].next.begin(),
+         rdfa->states[DEAD_STATE].next.end(), DEAD_STATE);
+
+    for (auto u : vertices_range(trie)) {
+        auto u_state = state_ids.at(u);
+        DEBUG_PRINTF("state %u\n", u_state);
+        assert(u_state < rdfa->states.size());
+        auto &ds = rdfa->states[u_state];
+        ds.reports = trie[u].reports;
+        if (!ds.reports.empty()) {
+            DEBUG_PRINTF("reports: %s\n", as_string_list(ds.reports).c_str());
+        }
+
+        // Set daddy state from failure map.
+        if (u == trie.root) {
+            ds.daddy = DEAD_STATE;
+        } else {
+            assert(contains(failure_map, u));
+            ds.daddy = state_ids.at(failure_map.at(u));
+        }
+
+        // By default, transition back to the root.
+        fill(ds.next.begin(), ds.next.end(), root_state);
+        // TOP should be a self-loop.
+        ds.next[alpha[TOP]] = u_state;
+
+        // Add in the real transitions.
+        for (auto v : adjacent_vertices_range(u, trie)) {
+            if (v == trie.root) {
+                continue;
+            }
+            auto v_state = state_ids.at(v);
+            u16 sym = alpha[trie[v].c];
+            DEBUG_PRINTF("edge to %u on 0x%02x (sym %u)\n", v_state,
+                         trie[v].c, sym);
+            assert(sym < ds.next.size());
+            assert(ds.next[sym] == root_state);
+            ds.next[sym] = v_state;
+        }
+    }
+
+    return rdfa;
+}
+
+#define MAX_GOOD_ACCEL_DEPTH 4
+
+static
+bool is_slow(const raw_dfa &rdfa, const set<dstate_id_t> &accel,
+             u32 roseQuality) {
+    /* we consider a dfa as slow if there is no way to quickly get into an accel
+     * state/dead state. In these cases, it is more likely that we will be
+     * running at our unaccelerated dfa speeds so the small write engine is only
+     * competitive over a small region where start up costs are dominant. */
+
+    if (roseQuality) {
+        return true;
+    }
+
+    set<dstate_id_t> visited;
+    set<dstate_id_t> next;
+    set<dstate_id_t> curr;
+    curr.insert(rdfa.start_anchored);
+
+    u32 ialpha_size = rdfa.getImplAlphaSize();
+
+    for (u32 i = 0; i < MAX_GOOD_ACCEL_DEPTH; i++) {
+        next.clear();
+        for (dstate_id_t s : curr) {
+            if (contains(visited, s)) {
+                continue;
+            }
+            visited.insert(s);
+            if (s == DEAD_STATE || contains(accel, s)) {
+                return false;
+            }
+
+            for (size_t j = 0; j < ialpha_size; j++) {
+                next.insert(rdfa.states[s].next[j]);
+            }
+        }
+        curr.swap(next);
+    }
+
+    return true;
+}
+
+static
+bytecode_ptr<NFA> getDfa(raw_dfa &rdfa, const CompileContext &cc,
+                         const ReportManager &rm, bool has_non_literals,
+                         set<dstate_id_t> &accel_states) {
+    // If we determinised only literals, then we only need to consider the init
+    // states for acceleration.
+    bool only_accel_init = !has_non_literals;
+    bool trust_daddy_states = !has_non_literals;
+
+    bytecode_ptr<NFA> dfa = nullptr;
+    if (cc.grey.allowSmallWriteSheng) {
+        dfa = shengCompile(rdfa, cc, rm, only_accel_init, &accel_states);
+        if (!dfa) {
+            dfa = sheng32Compile(rdfa, cc, rm, only_accel_init, &accel_states);
+        }
+        if (!dfa) {
+            dfa = sheng64Compile(rdfa, cc, rm, only_accel_init, &accel_states);
+        }
+    }
+    if (!dfa) {
+        dfa = mcclellanCompile(rdfa, cc, rm, only_accel_init,
+                               trust_daddy_states, &accel_states);
+    }
+    return dfa;
+}
+
+static
+bytecode_ptr<NFA> prepEngine(raw_dfa &rdfa, u32 roseQuality,
+                             const CompileContext &cc, const ReportManager &rm,
+                             bool has_non_literals, u32 *start_offset,
+                             u32 *small_region) {
+    *start_offset = remove_leading_dots(rdfa);
+
+    // Unleash the McClellan!
+    set<dstate_id_t> accel_states;
+
+    auto nfa = getDfa(rdfa, cc, rm, has_non_literals, accel_states);
+    if (!nfa) {
+        DEBUG_PRINTF("DFA compile failed for smallwrite NFA\n");
+        return nullptr;
+    }
+
+    if (is_slow(rdfa, accel_states, roseQuality)) {
+        DEBUG_PRINTF("is slow\n");
+        *small_region = cc.grey.smallWriteLargestBufferBad;
+        if (*small_region <= *start_offset) {
+            return nullptr;
+        }
+        if (clear_deeper_reports(rdfa, *small_region - *start_offset)) {
+            minimize_hopcroft(rdfa, cc.grey);
+            if (rdfa.start_anchored == DEAD_STATE) {
+                DEBUG_PRINTF("all patterns pruned out\n");
+                return nullptr;
+            }
+
+            nfa = getDfa(rdfa, cc, rm, has_non_literals, accel_states);
+            if (!nfa) {
+                DEBUG_PRINTF("DFA compile failed for smallwrite NFA\n");
+                assert(0); /* able to build orig dfa but not the trimmed? */
+                return nullptr;
+            }
+        }
+    } else {
+        *small_region = cc.grey.smallWriteLargestBuffer;
+    }
+
+    assert(isDfaType(nfa->type));
+    if (nfa->length > cc.grey.limitSmallWriteOutfixSize
+        || nfa->length > cc.grey.limitDFASize) {
+        DEBUG_PRINTF("smallwrite outfix size too large\n");
+        return nullptr; /* this is just a soft failure - don't build smwr */
+    }
+
+    nfa->queueIndex = 0; /* dummy, small write API does not use queue */
+    return nfa;
+}
+
+// SmallWriteBuild factory
+unique_ptr<SmallWriteBuild> makeSmallWriteBuilder(size_t num_patterns,
+                                                  const ReportManager &rm,
+                                                  const CompileContext &cc) {
+    return ue2::make_unique<SmallWriteBuildImpl>(num_patterns, rm, cc);
+}
+
+bytecode_ptr<SmallWriteEngine> SmallWriteBuildImpl::build(u32 roseQuality) {
+    const bool has_literals = !is_empty(lit_trie) || !is_empty(lit_trie_nocase);
+    const bool has_non_literals = !dfas.empty();
+    if (dfas.empty() && !has_literals) {
+        DEBUG_PRINTF("no smallwrite engine\n");
+        poisoned = true;
+        return nullptr;
+    }
+
+    if (poisoned) {
+        DEBUG_PRINTF("some pattern could not be made into a smallwrite dfa\n");
+        return nullptr;
+    }
+
+    // We happen to know that if the rose is high quality, we're going to limit
+    // depth further.
+    if (roseQuality) {
+        u32 max_depth = cc.grey.smallWriteLargestBufferBad;
+        if (!is_empty(lit_trie)) {
+            pruneTrie(lit_trie, max_depth);
+        }
+        if (!is_empty(lit_trie_nocase)) {
+            pruneTrie(lit_trie_nocase, max_depth);
+        }
+    }
+
+    if (!is_empty(lit_trie)) {
+        dfas.push_back(buildDfa(lit_trie, false));
+        DEBUG_PRINTF("caseful literal dfa with %zu states\n",
+                     dfas.back()->states.size());
+    }
+    if (!is_empty(lit_trie_nocase)) {
+        dfas.push_back(buildDfa(lit_trie_nocase, true));
+        DEBUG_PRINTF("nocase literal dfa with %zu states\n",
+                     dfas.back()->states.size());
+    }
+
+    if (dfas.empty()) {
+        DEBUG_PRINTF("no dfa, pruned everything away\n");
+        return nullptr;
+    }
+
+    if (!mergeDfas(dfas, rm, cc)) {
+        dfas.clear();
+        return nullptr;
+    }
+
+    assert(dfas.size() == 1);
+    auto rdfa = std::move(dfas.front());
+    dfas.clear();
+
+    DEBUG_PRINTF("building rdfa %p\n", rdfa.get());
+
+    u32 start_offset;
+    u32 small_region;
+    auto nfa = prepEngine(*rdfa, roseQuality, cc, rm, has_non_literals,
+                          &start_offset, &small_region);
+    if (!nfa) {
+        DEBUG_PRINTF("some smallwrite outfix could not be prepped\n");
+        /* just skip the smallwrite optimization */
+        poisoned = true;
+        return nullptr;
+    }
+
+    u32 size = sizeof(SmallWriteEngine) + nfa->length;
+    auto smwr = make_zeroed_bytecode_ptr<SmallWriteEngine>(size);
+
+    smwr->size = size;
+    smwr->start_offset = start_offset;
+    smwr->largestBuffer = small_region;
+
+    /* copy in nfa after the smwr */
+    assert(ISALIGNED_CL(smwr.get() + 1));
+    memcpy(smwr.get() + 1, nfa.get(), nfa->length);
+
+    DEBUG_PRINTF("smallwrite done %p\n", smwr.get());
+    return smwr;
+}
+
+set<ReportID> SmallWriteBuildImpl::all_reports() const {
+    set<ReportID> reports;
+    if (poisoned) {
+        return reports;
+    }
+
+    for (const auto &rdfa : dfas) {
+        insert(&reports, ::ue2::all_reports(*rdfa));
+    }
+
+    insert(&reports, ::ue2::all_reports(lit_trie));
+    insert(&reports, ::ue2::all_reports(lit_trie_nocase));
+
+    return reports;
+}
+
+} // namespace ue2
diff --git a/contrib/libs/hyperscan/src/smallwrite/smallwrite_build.h b/contrib/libs/hyperscan/src/smallwrite/smallwrite_build.h
new file mode 100644
index 0000000000..648b13db79
--- /dev/null
+++ b/contrib/libs/hyperscan/src/smallwrite/smallwrite_build.h
@@ -0,0 +1,80 @@
+/*
+ * Copyright (c) 2015-2017, Intel Corporation
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *  * Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *  * Neither the name of Intel Corporation nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SMWR_BUILD_H
+#define SMWR_BUILD_H
+
+/**
+ * \file
+ * \brief Small-write engine build interface.
+ *
+ * Everything you ever needed to feed literals in and get a SmallWriteEngine
+ * out. This header should be everything needed by the rest of UE2.
+ */
+
+#include "ue2common.h"
+#include "util/bytecode_ptr.h"
+#include "util/noncopyable.h"
+
+#include <memory>
+#include <set>
+
+struct SmallWriteEngine;
+
+namespace ue2 {
+
+struct CompileContext;
+struct ue2_literal;
+class ExpressionInfo;
+class NGHolder;
+class ReportManager;
+
+/**
+ * Abstract interface intended for callers from elsewhere in the tree, real
+ * underlying implementation is SmallWriteBuildImpl in smwr_build_impl.h.
+ */
+class SmallWriteBuild : noncopyable {
+public:
+    virtual ~SmallWriteBuild();
+
+    virtual bytecode_ptr<SmallWriteEngine> build(u32 roseQuality) = 0;
+
+    virtual void add(const NGHolder &g, const ExpressionInfo &expr) = 0;
+    virtual void add(const ue2_literal &literal, ReportID r) = 0;
+
+    virtual std::set<ReportID> all_reports() const = 0;
+};
+
+/** \brief Construct a usable SmallWrite builder. */
+std::unique_ptr<SmallWriteBuild>
+makeSmallWriteBuilder(size_t num_patterns, const ReportManager &rm,
+                      const CompileContext &cc);
+
+} // namespace ue2
+
+#endif // SMWR_BUILD_H
diff --git a/contrib/libs/hyperscan/src/smallwrite/smallwrite_internal.h b/contrib/libs/hyperscan/src/smallwrite/smallwrite_internal.h
new file mode 100644
index 0000000000..8f350dbeaa
--- /dev/null
+++ b/contrib/libs/hyperscan/src/smallwrite/smallwrite_internal.h
@@ -0,0 +1,53 @@
+/*
+ * Copyright (c) 2015, Intel Corporation
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *  * Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *  * Neither the name of Intel Corporation nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SMALLWRITE_INTERNAL_H
+#define SMALLWRITE_INTERNAL_H
+
+#include "ue2common.h"
+
+// Runtime structure header for SmallWrite.
+struct ALIGN_CL_DIRECTIVE SmallWriteEngine {
+    u32 largestBuffer; /**< largest buffer that can be considered small write */
+    u32 start_offset; /**< where to start scanning in the buffer. */
+    u32 size; /**< size of the small write engine in bytes (including the nfa) */
+};
+
+struct NFA;
+
+static really_inline
+const struct NFA *getSmwrNfa(const struct SmallWriteEngine *smwr) {
+    assert(smwr);
+    const struct NFA *n
+        = (const struct NFA *)((const char *)smwr + sizeof(*smwr));
+    assert(ISALIGNED_CL(n));
+    return n;
+}
+
+#endif // SMALLWRITE_INTERNAL_H
+