Move dfa's to tables.h

2025-06-23 14:15:05 -04:00
parent 5df9d958ab
commit 451c07747e
4 changed files with 631 additions and 629 deletions
--- a/src/fuzz.cpp
+++ b/src/fuzz.cpp
@@ -179,7 +179,7 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
    json_utf8 = json_utf8 && c >= 0x20 && c != '"' && c != '\\';
  }
  if (json_utf8) {
-    parser3::Utf8Dfa dfa;
+    Utf8Dfa dfa;
    auto result = dfa.scan((const char *)data, (const char *)data + size);
    bool ok = result == (const char *)data + size && dfa.accept();
    bool valid = simdjson::validate_utf8(s.data(), s.size());
--- a/src/parser3.h
+++ b/src/parser3.h
@@ -16,632 +16,6 @@

 namespace parser3 {

-// See https://gist.github.com/pervognsen/218ea17743e1442e59bb60d29b1aa725 for
-// an explanation of this cycle/byte dfa implementation.
-//
-// Recognizes json number syntax. As a regex:
-// -?([0-9]|[1-9][0-9]*)(\.[0-9]+)?((e|E)(-|\+)?[0-9]+)?
-struct NumDfa {
-  constexpr static uint64_t table[256] = {
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x36000ull,
-      0x0ull,
-      0x36600ull,
-      0x12480000000000ull,
-      0x0ull,
-      0x780aa47b091ec00ull,
-      0x780aa47aa91ea80ull,
-      0x780aa47aa91ea80ull,
-      0x780aa47aa91ea80ull,
-      0x780aa47aa91ea80ull,
-      0x780aa47aa91ea80ull,
-      0x780aa47aa91ea80ull,
-      0x780aa47aa91ea80ull,
-      0x780aa47aa91ea80ull,
-      0x780aa47aa91ea80ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0xc30c000000000ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0xc30c000000000ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-  };
-  // Restore this dfa to its start state
-  void reset() { state = 6; }
-  // Return true if this dfa is in an accept state. You probably want to call
-  // scan until the match ends first.
-  bool accept() const {
-    return (state & 63) == 30 || (state & 63) == 36 || (state & 63) == 48 ||
-           (state & 63) == 42;
-  }
-  // clang-format off
-#ifdef __x86_64__
-  __attribute__((target_clones("default", "bmi2")))
-#endif
-  // Return value either points to the first byte which does not match, or bufEnd.
-  // Leaves the dfa in the last state of the match.
-  const char *scan(const char *buf, const char *bufEnd) {
-    // clang-format on
-    auto state_ = state;
-    for (;;) {
-      constexpr int kStride = 16;
-      if (bufEnd - buf < kStride) [[unlikely]] {
-        while (buf != bufEnd) {
-          uint64_t row = table[uint8_t(*buf)];
-          auto prev = state_;
-          state_ = (row >> (state_ & 63)) & 63;
-          if (state_ == 0) {
-            state_ = prev;
-            break;
-          }
-          ++buf;
-        }
-        state = state_;
-        return buf;
-      }
-      uint8_t prev[kStride + 1];
-      prev[0] = state_;
-      for (int i = 0; i < kStride; ++i) {
-        uint64_t row = table[uint8_t(*buf)];
-        prev[i + 1] = row >> (prev[i] & 63);
-        if ((prev[i + 1] & 63) == 0) {
-          state = prev[i];
-          return buf;
-        }
-        ++buf;
-      }
-      state_ = prev[kStride];
-    }
-  }
-
-private:
-  uint64_t state = 6;
-};
-
-// Recognizes sequences of valid utf8 characters except 0-0x20, double quote,
-// and backslash
-struct Utf8Dfa {
-  constexpr static uint64_t table[256] = {
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x0ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x0ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x30000000000000ull,
-      0x18630780780ull,
-      0x18630780780ull,
-      0x18630780780ull,
-      0x18630780780ull,
-      0x18630780780ull,
-      0x18630780780ull,
-      0x18630780780ull,
-      0x18630780780ull,
-      0x18630780780ull,
-      0x18630780780ull,
-      0x18630780780ull,
-      0x18630780780ull,
-      0x18630780780ull,
-      0x18630780780ull,
-      0x18630780780ull,
-      0x18630780780ull,
-      0x1863001e780ull,
-      0x1863001e780ull,
-      0x1863001e780ull,
-      0x1863001e780ull,
-      0x1863001e780ull,
-      0x1863001e780ull,
-      0x1863001e780ull,
-      0x1863001e780ull,
-      0x1863001e780ull,
-      0x1863001e780ull,
-      0x1863001e780ull,
-      0x1863001e780ull,
-      0x1863001e780ull,
-      0x1863001e780ull,
-      0x1863001e780ull,
-      0x1863001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x60063001e780ull,
-      0x0ull,
-      0x0ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x18000000000000ull,
-      0x2a000000000000ull,
-      0x1e000000000000ull,
-      0x1e000000000000ull,
-      0x1e000000000000ull,
-      0x1e000000000000ull,
-      0x1e000000000000ull,
-      0x1e000000000000ull,
-      0x1e000000000000ull,
-      0x1e000000000000ull,
-      0x1e000000000000ull,
-      0x1e000000000000ull,
-      0x1e000000000000ull,
-      0x1e000000000000ull,
-      0x24000000000000ull,
-      0x1e000000000000ull,
-      0x1e000000000000ull,
-      0xc000000000000ull,
-      0x6000000000000ull,
-      0x6000000000000ull,
-      0x6000000000000ull,
-      0x12000000000000ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-      0x0ull,
-  };
-  // Restore this dfa to its start state
-  void reset() { state = 48; }
-  // Return true if this dfa is in an accept state. You probably want to call
-  // scan until the match ends first.
-  bool accept() const { return (state & 63) == 48; }
-  // clang-format off
-#ifdef __x86_64__
-  __attribute__((target_clones("default", "bmi2")))
-#endif
-  // Return value either points to the first byte which does not match, or bufEnd.
-  // Leaves the dfa in the last state of the match.
-  const char *scan(const char *buf, const char *bufEnd) {
-    // clang-format on
-    auto state_ = state;
-    for (;;) {
-      constexpr int kStride = 16;
-      if (bufEnd - buf < kStride) [[unlikely]] {
-        while (buf != bufEnd) {
-          uint64_t row = table[uint8_t(*buf)];
-          auto prev = state_;
-          state_ = (row >> (state_ & 63)) & 63;
-          if (state_ == 0) {
-            state_ = prev;
-            break;
-          }
-          ++buf;
-        }
-        state = state_;
-        return buf;
-      }
-      uint8_t prev[kStride + 1];
-      prev[0] = state_;
-      for (int i = 0; i < kStride; ++i) {
-        uint64_t row = table[uint8_t(*buf)];
-        prev[i + 1] = row >> (prev[i] & 63);
-        if ((prev[i + 1] & 63) == 0) {
-          state = prev[i];
-          return buf;
-        }
-        ++buf;
-      }
-      state_ = prev[kStride];
-    }
-  }
-
-private:
-  uint64_t state = 48;
-};
-
 typedef PRESERVE_NONE WeaselJsonStatus (*Continuation)(struct Parser3 *,
                                                       char *buf, char *bufEnd);

--- a/src/tables.h
+++ b/src/tables.h
@@ -1,5 +1,7 @@
 #pragma once

+#include <cstdint>
+
 constexpr inline struct Tables {

  constexpr Tables() {
@@ -19,3 +21,629 @@ constexpr inline struct Tables {
  bool whitespace[256]{};
  char unescape[256]{};
 } tables;
+
+// See https://gist.github.com/pervognsen/218ea17743e1442e59bb60d29b1aa725 for
+// an explanation of this cycle/byte dfa implementation.
+//
+// Recognizes json number syntax. As a regex:
+// -?([0-9]|[1-9][0-9]*)(\.[0-9]+)?((e|E)(-|\+)?[0-9]+)?
+struct NumDfa {
+  constexpr static uint64_t table[256] = {
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x36000ull,
+      0x0ull,
+      0x36600ull,
+      0x12480000000000ull,
+      0x0ull,
+      0x780aa47b091ec00ull,
+      0x780aa47aa91ea80ull,
+      0x780aa47aa91ea80ull,
+      0x780aa47aa91ea80ull,
+      0x780aa47aa91ea80ull,
+      0x780aa47aa91ea80ull,
+      0x780aa47aa91ea80ull,
+      0x780aa47aa91ea80ull,
+      0x780aa47aa91ea80ull,
+      0x780aa47aa91ea80ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0xc30c000000000ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0xc30c000000000ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+  };
+  // Restore this dfa to its start state
+  void reset() { state = 6; }
+  // Return true if this dfa is in an accept state. You probably want to call
+  // scan until the match ends first.
+  bool accept() const {
+    return (state & 63) == 30 || (state & 63) == 36 || (state & 63) == 48 ||
+           (state & 63) == 42;
+  }
+  // clang-format off
+#ifdef __x86_64__
+  __attribute__((target_clones("default", "bmi2")))
+#endif
+  // Return value either points to the first byte which does not match, or bufEnd.
+  // Leaves the dfa in the last state of the match.
+  const char *scan(const char *buf, const char *bufEnd) {
+    // clang-format on
+    auto state_ = state;
+    for (;;) {
+      constexpr int kStride = 16;
+      if (bufEnd - buf < kStride) [[unlikely]] {
+        while (buf != bufEnd) {
+          uint64_t row = table[uint8_t(*buf)];
+          auto prev = state_;
+          state_ = (row >> (state_ & 63)) & 63;
+          if (state_ == 0) {
+            state_ = prev;
+            break;
+          }
+          ++buf;
+        }
+        state = state_;
+        return buf;
+      }
+      uint8_t prev[kStride + 1];
+      prev[0] = state_;
+      for (int i = 0; i < kStride; ++i) {
+        uint64_t row = table[uint8_t(*buf)];
+        prev[i + 1] = row >> (prev[i] & 63);
+        if ((prev[i + 1] & 63) == 0) {
+          state = prev[i];
+          return buf;
+        }
+        ++buf;
+      }
+      state_ = prev[kStride];
+    }
+  }
+
+private:
+  uint64_t state = 6;
+};
+
+// Recognizes sequences of valid utf8 characters except 0-0x20, double quote,
+// and backslash
+struct Utf8Dfa {
+  constexpr static uint64_t table[256] = {
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x0ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x0ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x30000000000000ull,
+      0x18630780780ull,
+      0x18630780780ull,
+      0x18630780780ull,
+      0x18630780780ull,
+      0x18630780780ull,
+      0x18630780780ull,
+      0x18630780780ull,
+      0x18630780780ull,
+      0x18630780780ull,
+      0x18630780780ull,
+      0x18630780780ull,
+      0x18630780780ull,
+      0x18630780780ull,
+      0x18630780780ull,
+      0x18630780780ull,
+      0x18630780780ull,
+      0x1863001e780ull,
+      0x1863001e780ull,
+      0x1863001e780ull,
+      0x1863001e780ull,
+      0x1863001e780ull,
+      0x1863001e780ull,
+      0x1863001e780ull,
+      0x1863001e780ull,
+      0x1863001e780ull,
+      0x1863001e780ull,
+      0x1863001e780ull,
+      0x1863001e780ull,
+      0x1863001e780ull,
+      0x1863001e780ull,
+      0x1863001e780ull,
+      0x1863001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x60063001e780ull,
+      0x0ull,
+      0x0ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x18000000000000ull,
+      0x2a000000000000ull,
+      0x1e000000000000ull,
+      0x1e000000000000ull,
+      0x1e000000000000ull,
+      0x1e000000000000ull,
+      0x1e000000000000ull,
+      0x1e000000000000ull,
+      0x1e000000000000ull,
+      0x1e000000000000ull,
+      0x1e000000000000ull,
+      0x1e000000000000ull,
+      0x1e000000000000ull,
+      0x1e000000000000ull,
+      0x24000000000000ull,
+      0x1e000000000000ull,
+      0x1e000000000000ull,
+      0xc000000000000ull,
+      0x6000000000000ull,
+      0x6000000000000ull,
+      0x6000000000000ull,
+      0x12000000000000ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+      0x0ull,
+  };
+  // Restore this dfa to its start state
+  void reset() { state = 48; }
+  // Return true if this dfa is in an accept state. You probably want to call
+  // scan until the match ends first.
+  bool accept() const { return (state & 63) == 48; }
+  // clang-format off
+#ifdef __x86_64__
+  __attribute__((target_clones("default", "bmi2")))
+#endif
+  // Return value either points to the first byte which does not match, or bufEnd.
+  // Leaves the dfa in the last state of the match.
+  const char *scan(const char *buf, const char *bufEnd) {
+    // clang-format on
+    auto state_ = state;
+    for (;;) {
+      constexpr int kStride = 16;
+      if (bufEnd - buf < kStride) [[unlikely]] {
+        while (buf != bufEnd) {
+          uint64_t row = table[uint8_t(*buf)];
+          auto prev = state_;
+          state_ = (row >> (state_ & 63)) & 63;
+          if (state_ == 0) {
+            state_ = prev;
+            break;
+          }
+          ++buf;
+        }
+        state = state_;
+        return buf;
+      }
+      uint8_t prev[kStride + 1];
+      prev[0] = state_;
+      for (int i = 0; i < kStride; ++i) {
+        uint64_t row = table[uint8_t(*buf)];
+        prev[i + 1] = row >> (prev[i] & 63);
+        if ((prev[i + 1] & 63) == 0) {
+          state = prev[i];
+          return buf;
+        }
+        ++buf;
+      }
+      state_ = prev[kStride];
+    }
+  }
+
+private:
+  uint64_t state = 48;
+};
--- a/src/test.cpp
+++ b/src/test.cpp
@@ -309,7 +309,7 @@ TEST_CASE("bench5") {
 }

 TEST_CASE("num dfa") {
-  parser3::NumDfa dfa;
+  NumDfa dfa;
  std::string match =
      "111111111111111111111111111111111111111111111111111111111111111111111111"
      "111111111111111111111111111111111111111111111111111111111111111111111111"
@@ -339,7 +339,7 @@ const char *utf8str =
    "💩💩💩💩💩💩💩💩💩💩💩💩💩💩💩💩💩💩💩💩💩💩💩💩";

 TEST_CASE("utf8 dfa") {
-  parser3::Utf8Dfa dfa;
+  Utf8Dfa dfa;
  std::string match = utf8str;
  auto *buf = dfa.scan(match.data(), match.data() + match.size());
  CHECK(buf == match.data() + match.size());