Initial commit of Hyperscan

src/nfa/vermicelli_run.h

@@ -0,0 +1,90 @@
+/*
+ * 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.
+ */
+
+#include "vermicelli.h"
+
+static really_inline
+const u8 *find_xverm_run(char c, char nocase, u32 repeat, UNUSED const u8 *buf,
+                         const u8 *buf_start, const u8 *buf_end, char negate) {
+    DEBUG_PRINTF("looking for 0x%hhx{%u} in %p [%zd, %zd)\n", c, repeat, buf,
+                  buf_start - buf, buf_end - buf);
+
+    /* TODO optimise on where it is easy to get a dense bitfield of character
+     * matches */
+    if (repeat == 1) {
+        return negate ? nvermicelliExec(c, nocase, buf_start, buf_end)
+                      : vermicelliExec(c, nocase, buf_start, buf_end);
+    }
+
+    while (1) {
+        const u8 *s;
+        if (negate) {
+            s = nvermicelliExec(c, nocase, buf_start, buf_end);
+        } else if (buf_end - buf_start >= VERM_BOUNDARY && !nocase) {
+            s = vermicelliDoubleExec(c, c, nocase, buf_start, buf_end);
+
+            if (s != buf_end && *s != c) { /* double verm is not certain to be
+                                            * precise */
+                s = vermicelliExec(c, nocase, s, buf_end);
+            }
+        } else {
+            s = vermicelliExec(c, nocase, buf_start, buf_end);
+        }
+        if (s == buf_end) {
+            return s;
+        }
+
+        DEBUG_PRINTF("cand %zd\n", s - buf);
+
+        const u8 *test_e = MIN(s + repeat, buf_end);
+
+        const u8 *rv = negate ? vermicelliExec(c, nocase, s, test_e)
+                              : nvermicelliExec(c, nocase, s, test_e);
+
+        assert(rv > buf_start);
+        assert(rv <= buf_end);
+
+        if (rv == test_e) {
+            return s;
+        }
+
+        buf_start = rv;
+    }
+}
+
+static really_inline
+const u8 *find_verm_run(char c, char nocase, u32 repeat, const u8 *buf,
+                        const u8 *buf_start, const u8 *buf_end) {
+    return find_xverm_run(c, nocase, repeat, buf, buf_start, buf_end, 0);
+}
+
+static really_inline
+const u8 *find_nverm_run(char c, char nocase, u32 repeat, const u8 *buf,
+                         const u8 *buf_start, const u8 *buf_end) {
+    return find_xverm_run(c, nocase, repeat, buf, buf_start, buf_end, 1);
+}