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-rw-r--r--src/rocksdb/util/crc32c_ppc.c94
1 files changed, 94 insertions, 0 deletions
diff --git a/src/rocksdb/util/crc32c_ppc.c b/src/rocksdb/util/crc32c_ppc.c
new file mode 100644
index 000000000..888a4943e
--- /dev/null
+++ b/src/rocksdb/util/crc32c_ppc.c
@@ -0,0 +1,94 @@
+// Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
+// Copyright (c) 2017 International Business Machines Corp.
+// All rights reserved.
+// This source code is licensed under both the GPLv2 (found in the
+// COPYING file in the root directory) and Apache 2.0 License
+// (found in the LICENSE.Apache file in the root directory).
+
+#define CRC_TABLE
+#include <stdint.h>
+#include <stdlib.h>
+#include <strings.h>
+#include "util/crc32c_ppc_constants.h"
+
+#define VMX_ALIGN 16
+#define VMX_ALIGN_MASK (VMX_ALIGN - 1)
+
+#ifdef REFLECT
+static unsigned int crc32_align(unsigned int crc, unsigned char const *p,
+ unsigned long len) {
+ while (len--) crc = crc_table[(crc ^ *p++) & 0xff] ^ (crc >> 8);
+ return crc;
+}
+#endif
+
+#ifdef HAVE_POWER8
+unsigned int __crc32_vpmsum(unsigned int crc, unsigned char const *p,
+ unsigned long len);
+
+static uint32_t crc32_vpmsum(uint32_t crc, unsigned char const *data,
+ unsigned len) {
+ unsigned int prealign;
+ unsigned int tail;
+
+#ifdef CRC_XOR
+ crc ^= 0xffffffff;
+#endif
+
+ if (len < VMX_ALIGN + VMX_ALIGN_MASK) {
+ crc = crc32_align(crc, data, (unsigned long)len);
+ goto out;
+ }
+
+ if ((unsigned long)data & VMX_ALIGN_MASK) {
+ prealign = VMX_ALIGN - ((unsigned long)data & VMX_ALIGN_MASK);
+ crc = crc32_align(crc, data, prealign);
+ len -= prealign;
+ data += prealign;
+ }
+
+ crc = __crc32_vpmsum(crc, data, (unsigned long)len & ~VMX_ALIGN_MASK);
+
+ tail = len & VMX_ALIGN_MASK;
+ if (tail) {
+ data += len & ~VMX_ALIGN_MASK;
+ crc = crc32_align(crc, data, tail);
+ }
+
+out:
+#ifdef CRC_XOR
+ crc ^= 0xffffffff;
+#endif
+
+ return crc;
+}
+
+/* This wrapper function works around the fact that crc32_vpmsum
+ * does not gracefully handle the case where the data pointer is NULL. There
+ * may be room for performance improvement here.
+ */
+uint32_t crc32c_ppc(uint32_t crc, unsigned char const *data, unsigned len) {
+ unsigned char *buf2;
+
+ if (!data) {
+ buf2 = (unsigned char *)malloc(len);
+ bzero(buf2, len);
+ crc = crc32_vpmsum(crc, buf2, len);
+ free(buf2);
+ } else {
+ crc = crc32_vpmsum(crc, data, (unsigned long)len);
+ }
+ return crc;
+}
+
+#else /* HAVE_POWER8 */
+
+/* This symbol has to exist on non-ppc architectures (and on legacy
+ * ppc systems using power7 or below) in order to compile properly
+ * there, even though it won't be called.
+ */
+uint32_t crc32c_ppc(uint32_t crc, unsigned char const *data, unsigned len) {
+ return 0;
+}
+
+#endif /* HAVE_POWER8 */