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-rw-r--r--src/isa-l/igzip/bitbuf2.h172
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diff --git a/src/isa-l/igzip/bitbuf2.h b/src/isa-l/igzip/bitbuf2.h
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+/**********************************************************************
+ Copyright(c) 2011-2016 Intel Corporation All rights reserved.
+
+ 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 BITBUF2_H
+#define BITBUF2_H
+
+#include "igzip_lib.h"
+
+/* bit buffer types
+ * BITBUF8: (e) Always write 8 bytes of data
+ * BITBUFB: (b) Always write data
+ */
+#if !(defined(USE_BITBUFB) || defined(USE_BITBUF8) || defined(USE_BITBUF_ELSE))
+# define USE_BITBUFB
+#endif
+
+#if defined (__unix__) || (__APPLE__) || (__MINGW32__)
+#define _mm_stream_si64x(dst, src) *((uint64_t*)dst) = src
+#else
+#include <intrin.h>
+#endif
+
+#ifdef _WIN64
+#pragma warning(disable: 4996)
+#endif
+
+#ifdef _MSC_VER
+#define inline __inline
+#endif
+
+
+/* MAX_BITBUF_BIT WRITE is the maximum number of bits than can be safely written
+ * by consecutive calls of write_bits. Note this assumes the bitbuf is in a
+ * state that is possible at the exit of write_bits */
+#ifdef USE_BITBUF8 /*Write bits safe */
+# define MAX_BITBUF_BIT_WRITE 63
+#elif defined(USE_BITBUFB) /* Write bits always */
+# define MAX_BITBUF_BIT_WRITE 56
+#else /* USE_BITBUF_ELSE */
+# define MAX_BITBUF_BIT_WRITE 56
+#endif
+
+
+static
+ inline void construct(struct BitBuf2 *me)
+{
+ me->m_bits = 0;
+ me->m_bit_count = 0;
+ me->m_out_buf = me->m_out_start = me->m_out_end = NULL;
+}
+
+static inline void init(struct BitBuf2 *me)
+{
+ me->m_bits = 0;
+ me->m_bit_count = 0;
+}
+
+static inline void set_buf(struct BitBuf2 *me, unsigned char *buf, unsigned int len)
+{
+ unsigned int slop = 8;
+ me->m_out_buf = me->m_out_start = buf;
+ me->m_out_end = buf + len - slop;
+}
+
+static inline int is_full(struct BitBuf2 *me)
+{
+ return (me->m_out_buf > me->m_out_end);
+}
+
+static inline uint8_t * buffer_ptr(struct BitBuf2 *me)
+{
+ return me->m_out_buf;
+}
+
+static inline uint32_t buffer_used(struct BitBuf2 *me)
+{
+ return (uint32_t)(me->m_out_buf - me->m_out_start);
+}
+
+static inline uint32_t buffer_bits_used(struct BitBuf2 *me)
+{
+ return (8 * (uint32_t)(me->m_out_buf - me->m_out_start) + me->m_bit_count);
+}
+
+static inline void flush_bits(struct BitBuf2 *me)
+{
+ uint32_t bits;
+ _mm_stream_si64x((int64_t *) me->m_out_buf, me->m_bits);
+ bits = me->m_bit_count & ~7;
+ me->m_bit_count -= bits;
+ me->m_out_buf += bits/8;
+ me->m_bits >>= bits;
+
+}
+
+static inline void check_space(struct BitBuf2 *me, uint32_t num_bits)
+{
+ /* Checks if bitbuf has num_bits extra space and flushes the bytes in
+ * the bitbuf if it doesn't. */
+ if (63 - me->m_bit_count < num_bits)
+ flush_bits(me);
+}
+
+static inline void write_bits_unsafe(struct BitBuf2 *me, uint64_t code, uint32_t count)
+{
+ me->m_bits |= code << me->m_bit_count;
+ me->m_bit_count += count;
+}
+
+static inline void write_bits(struct BitBuf2 *me, uint64_t code, uint32_t count)
+{
+#ifdef USE_BITBUF8 /*Write bits safe */
+ me->m_bits |= code << me->m_bit_count;
+ me->m_bit_count += count;
+ if (me->m_bit_count >= 64) {
+ _mm_stream_si64x((int64_t *) me->m_out_buf, me->m_bits);
+ me->m_out_buf += 8;
+ me->m_bit_count -= 64;
+ me->m_bits = code >> (count - me->m_bit_count);
+ }
+#elif defined(USE_BITBUFB) /* Write bits always */
+ /* Assumes there is space to fit code into m_bits. */
+ me->m_bits |= code << me->m_bit_count;
+ me->m_bit_count += count;
+ if (me->m_bit_count >= 8)
+ flush_bits(me);
+#else /* USE_BITBUF_ELSE */
+ check_space(me, count);
+ write_bits_unsafe(me, code, count);
+#endif
+
+}
+
+/* Can write up to 8 bytes to output buffer */
+static inline void flush(struct BitBuf2 *me)
+{
+ uint32_t bytes;
+ if (me->m_bit_count) {
+ _mm_stream_si64x((int64_t *) me->m_out_buf, me->m_bits);
+ bytes = (me->m_bit_count + 7) / 8;
+ me->m_out_buf += bytes;
+ }
+ me->m_bits = 0;
+ me->m_bit_count = 0;
+}
+
+#endif //BITBUF2_H