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-rw-r--r--vere/ext/nasm/nasmlib/perfhash.c55
1 files changed, 55 insertions, 0 deletions
diff --git a/vere/ext/nasm/nasmlib/perfhash.c b/vere/ext/nasm/nasmlib/perfhash.c
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+++ b/vere/ext/nasm/nasmlib/perfhash.c
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+/* ----------------------------------------------------------------------- *
+ *
+ * Copyright 2017 The NASM Authors - All Rights Reserved
+ * See the file AUTHORS included with the NASM distribution for
+ * the specific copyright holders.
+ *
+ * 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.
+ *
+ * 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 "perfhash.h"
+#include "hashtbl.h" /* For crc64i() */
+
+int perfhash_find(const struct perfect_hash *hash, const char *str)
+{
+ uint32_t k1, k2;
+ uint64_t crc;
+ uint16_t ix;
+
+ crc = crc64i(hash->crcinit, str);
+ k1 = (uint32_t)crc & hash->hashmask;
+ k2 = ((uint32_t)(crc >> 32) & hash->hashmask) + 1;
+
+ ix = hash->hashvals[k1] + hash->hashvals[k2];
+
+ if (ix >= hash->tbllen ||
+ !hash->strings[ix] ||
+ nasm_stricmp(str, hash->strings[ix]))
+ return hash->errval;
+
+ return hash->tbloffs + ix;
+}