Adding upstream version 1:115.7.0.upstream/1%115.7.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 178 insertions, 0 deletions

diff --git a/third_party/dav1d/src/getbits.c b/third_party/dav1d/src/getbits.c
new file mode 100644
index 0000000000..673070be3d
--- /dev/null
+++ b/third_party/dav1d/src/getbits.c
@@ -0,0 +1,178 @@
+/*
+ * Copyright © 2018, VideoLAN and dav1d authors
+ * Copyright © 2018, Two Orioles, LLC
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. 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 "config.h"
+
+#include <limits.h>
+
+#include "common/intops.h"
+
+#include "src/getbits.h"
+
+void dav1d_init_get_bits(GetBits *const c, const uint8_t *const data,
+                         const size_t sz)
+{
+    assert(sz);
+    c->ptr = c->ptr_start = data;
+    c->ptr_end = &c->ptr_start[sz];
+    c->state = 0;
+    c->bits_left = 0;
+    c->error = 0;
+}
+
+unsigned dav1d_get_bit(GetBits *const c) {
+    if (!c->bits_left) {
+        if (c->ptr >= c->ptr_end) {
+            c->error = 1;
+        } else {
+            const unsigned state = *c->ptr++;
+            c->bits_left = 7;
+            c->state = (uint64_t) state << 57;
+            return state >> 7;
+        }
+    }
+
+    const uint64_t state = c->state;
+    c->bits_left--;
+    c->state = state << 1;
+    return (unsigned) (state >> 63);
+}
+
+static inline void refill(GetBits *const c, const int n) {
+    assert(c->bits_left >= 0 && c->bits_left < 32);
+    unsigned state = 0;
+    do {
+        if (c->ptr >= c->ptr_end) {
+            c->error = 1;
+            if (state) break;
+            return;
+        }
+        state = (state << 8) | *c->ptr++;
+        c->bits_left += 8;
+    } while (n > c->bits_left);
+    c->state |= (uint64_t) state << (64 - c->bits_left);
+}
+
+#define GET_BITS(name, type, type64)            \
+type name(GetBits *const c, const int n) {      \
+    assert(n > 0 && n <= 32);                   \
+    /* Unsigned cast avoids refill after eob */ \
+    if ((unsigned) n > (unsigned) c->bits_left) \
+        refill(c, n);                           \
+    const uint64_t state = c->state;            \
+    c->bits_left -= n;                          \
+    c->state = state << n;                      \
+    return (type) ((type64) state >> (64 - n)); \
+}
+
+GET_BITS(dav1d_get_bits,  unsigned, uint64_t)
+GET_BITS(dav1d_get_sbits, int,      int64_t)
+
+unsigned dav1d_get_uleb128(GetBits *const c) {
+    uint64_t val = 0;
+    unsigned i = 0, more;
+
+    do {
+        const int v = dav1d_get_bits(c, 8);
+        more = v & 0x80;
+        val |= ((uint64_t) (v & 0x7F)) << i;
+        i += 7;
+    } while (more && i < 56);
+
+    if (val > UINT_MAX || more) {
+        c->error = 1;
+        return 0;
+    }
+
+    return (unsigned) val;
+}
+
+unsigned dav1d_get_uniform(GetBits *const c, const unsigned max) {
+    // Output in range [0..max-1]
+    // max must be > 1, or else nothing is read from the bitstream
+    assert(max > 1);
+    const int l = ulog2(max) + 1;
+    assert(l > 1);
+    const unsigned m = (1U << l) - max;
+    const unsigned v = dav1d_get_bits(c, l - 1);
+    return v < m ? v : (v << 1) - m + dav1d_get_bit(c);
+}
+
+unsigned dav1d_get_vlc(GetBits *const c) {
+    if (dav1d_get_bit(c))
+        return 0;
+
+    int n_bits = 0;
+    do {
+        if (++n_bits == 32)
+            return 0xFFFFFFFFU;
+    } while (!dav1d_get_bit(c));
+
+    return ((1U << n_bits) - 1) + dav1d_get_bits(c, n_bits);
+}
+
+static unsigned get_bits_subexp_u(GetBits *const c, const unsigned ref,
+                                  const unsigned n)
+{
+    unsigned v = 0;
+
+    for (int i = 0;; i++) {
+        const int b = i ? 3 + i - 1 : 3;
+
+        if (n < v + 3 * (1 << b)) {
+            v += dav1d_get_uniform(c, n - v + 1);
+            break;
+        }
+
+        if (!dav1d_get_bit(c)) {
+            v += dav1d_get_bits(c, b);
+            break;
+        }
+
+        v += 1 << b;
+    }
+
+    return ref * 2 <= n ? inv_recenter(ref, v) : n - inv_recenter(n - ref, v);
+}
+
+int dav1d_get_bits_subexp(GetBits *const c, const int ref, const unsigned n) {
+    return (int) get_bits_subexp_u(c, ref + (1 << n), 2 << n) - (1 << n);
+}
+
+void dav1d_bytealign_get_bits(GetBits *c) {
+    // bits_left is never more than 7, because it is only incremented
+    // by refill(), called by dav1d_get_bits and that never reads more
+    // than 7 bits more than it needs.
+    //
+    // If this wasn't true, we would need to work out how many bits to
+    // discard (bits_left % 8), subtract that from bits_left and then
+    // shift state right by that amount.
+    assert(c->bits_left <= 7);
+
+    c->bits_left = 0;
+    c->state = 0;
+}