Adding upstream version 124.0.1.upstream/124.0.1

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

1 files changed, 208 insertions, 0 deletions

diff --git a/third_party/dav1d/src/msac.c b/third_party/dav1d/src/msac.c
new file mode 100644
index 0000000000..43d8ae5d07
--- /dev/null
+++ b/third_party/dav1d/src/msac.c
@@ -0,0 +1,208 @@
+/*
+ * 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/msac.h"
+
+#define EC_PROB_SHIFT 6
+#define EC_MIN_PROB 4  // must be <= (1<<EC_PROB_SHIFT)/16
+
+#define EC_WIN_SIZE (sizeof(ec_win) << 3)
+
+static inline void ctx_refill(MsacContext *const s) {
+    const uint8_t *buf_pos = s->buf_pos;
+    const uint8_t *buf_end = s->buf_end;
+    int c = EC_WIN_SIZE - s->cnt - 24;
+    ec_win dif = s->dif;
+    while (c >= 0 && buf_pos < buf_end) {
+        dif ^= ((ec_win)*buf_pos++) << c;
+        c -= 8;
+    }
+    s->dif = dif;
+    s->cnt = EC_WIN_SIZE - c - 24;
+    s->buf_pos = buf_pos;
+}
+
+/* Takes updated dif and range values, renormalizes them so that
+ * 32768 <= rng < 65536 (reading more bytes from the stream into dif if
+ * necessary), and stores them back in the decoder context.
+ * dif: The new value of dif.
+ * rng: The new value of the range. */
+static inline void ctx_norm(MsacContext *const s, const ec_win dif,
+                            const unsigned rng)
+{
+    const int d = 15 ^ (31 ^ clz(rng));
+    assert(rng <= 65535U);
+    s->cnt -= d;
+    s->dif = ((dif + 1) << d) - 1; /* Shift in 1s in the LSBs */
+    s->rng = rng << d;
+    if (s->cnt < 0)
+        ctx_refill(s);
+}
+
+unsigned dav1d_msac_decode_bool_equi_c(MsacContext *const s) {
+    const unsigned r = s->rng;
+    ec_win dif = s->dif;
+    assert((dif >> (EC_WIN_SIZE - 16)) < r);
+    // When the probability is 1/2, f = 16384 >> EC_PROB_SHIFT = 256 and we can
+    // replace the multiply with a simple shift.
+    unsigned v = ((r >> 8) << 7) + EC_MIN_PROB;
+    const ec_win vw = (ec_win)v << (EC_WIN_SIZE - 16);
+    const unsigned ret = dif >= vw;
+    dif -= ret * vw;
+    v += ret * (r - 2 * v);
+    ctx_norm(s, dif, v);
+    return !ret;
+}
+
+/* Decode a single binary value.
+ * f: The probability that the bit is one
+ * Return: The value decoded (0 or 1). */
+unsigned dav1d_msac_decode_bool_c(MsacContext *const s, const unsigned f) {
+    const unsigned r = s->rng;
+    ec_win dif = s->dif;
+    assert((dif >> (EC_WIN_SIZE - 16)) < r);
+    unsigned v = ((r >> 8) * (f >> EC_PROB_SHIFT) >> (7 - EC_PROB_SHIFT)) + EC_MIN_PROB;
+    const ec_win vw = (ec_win)v << (EC_WIN_SIZE - 16);
+    const unsigned ret = dif >= vw;
+    dif -= ret * vw;
+    v += ret * (r - 2 * v);
+    ctx_norm(s, dif, v);
+    return !ret;
+}
+
+int dav1d_msac_decode_subexp(MsacContext *const s, const int ref,
+                             const int n, unsigned k)
+{
+    assert(n >> k == 8);
+
+    unsigned a = 0;
+    if (dav1d_msac_decode_bool_equi(s)) {
+        if (dav1d_msac_decode_bool_equi(s))
+            k += dav1d_msac_decode_bool_equi(s) + 1;
+        a = 1 << k;
+    }
+    const unsigned v = dav1d_msac_decode_bools(s, k) + a;
+    return ref * 2 <= n ? inv_recenter(ref, v) :
+                          n - 1 - inv_recenter(n - 1 - ref, v);
+}
+
+/* Decodes a symbol given an inverse cumulative distribution function (CDF)
+ * table in Q15. */
+unsigned dav1d_msac_decode_symbol_adapt_c(MsacContext *const s,
+                                          uint16_t *const cdf,
+                                          const size_t n_symbols)
+{
+    const unsigned c = s->dif >> (EC_WIN_SIZE - 16), r = s->rng >> 8;
+    unsigned u, v = s->rng, val = -1;
+
+    assert(n_symbols <= 15);
+    assert(cdf[n_symbols] <= 32);
+
+    do {
+        val++;
+        u = v;
+        v = r * (cdf[val] >> EC_PROB_SHIFT);
+        v >>= 7 - EC_PROB_SHIFT;
+        v += EC_MIN_PROB * ((unsigned)n_symbols - val);
+    } while (c < v);
+
+    assert(u <= s->rng);
+
+    ctx_norm(s, s->dif - ((ec_win)v << (EC_WIN_SIZE - 16)), u - v);
+
+    if (s->allow_update_cdf) {
+        const unsigned count = cdf[n_symbols];
+        const unsigned rate = 4 + (count >> 4) + (n_symbols > 2);
+        unsigned i;
+        for (i = 0; i < val; i++)
+            cdf[i] += (32768 - cdf[i]) >> rate;
+        for (; i < n_symbols; i++)
+            cdf[i] -= cdf[i] >> rate;
+        cdf[n_symbols] = count + (count < 32);
+    }
+
+    return val;
+}
+
+unsigned dav1d_msac_decode_bool_adapt_c(MsacContext *const s,
+                                        uint16_t *const cdf)
+{
+    const unsigned bit = dav1d_msac_decode_bool(s, *cdf);
+
+    if (s->allow_update_cdf) {
+        // update_cdf() specialized for boolean CDFs
+        const unsigned count = cdf[1];
+        const int rate = 4 + (count >> 4);
+        if (bit)
+            cdf[0] += (32768 - cdf[0]) >> rate;
+        else
+            cdf[0] -= cdf[0] >> rate;
+        cdf[1] = count + (count < 32);
+    }
+
+    return bit;
+}
+
+unsigned dav1d_msac_decode_hi_tok_c(MsacContext *const s, uint16_t *const cdf) {
+    unsigned tok_br = dav1d_msac_decode_symbol_adapt4(s, cdf, 3);
+    unsigned tok = 3 + tok_br;
+    if (tok_br == 3) {
+        tok_br = dav1d_msac_decode_symbol_adapt4(s, cdf, 3);
+        tok = 6 + tok_br;
+        if (tok_br == 3) {
+            tok_br = dav1d_msac_decode_symbol_adapt4(s, cdf, 3);
+            tok = 9 + tok_br;
+            if (tok_br == 3)
+                tok = 12 + dav1d_msac_decode_symbol_adapt4(s, cdf, 3);
+        }
+    }
+    return tok;
+}
+
+void dav1d_msac_init(MsacContext *const s, const uint8_t *const data,
+                     const size_t sz, const int disable_cdf_update_flag)
+{
+    s->buf_pos = data;
+    s->buf_end = data + sz;
+    s->dif = ((ec_win)1 << (EC_WIN_SIZE - 1)) - 1;
+    s->rng = 0x8000;
+    s->cnt = -15;
+    s->allow_update_cdf = !disable_cdf_update_flag;
+    ctx_refill(s);
+
+#if ARCH_X86_64 && HAVE_ASM
+    s->symbol_adapt16 = dav1d_msac_decode_symbol_adapt_c;
+
+    msac_init_x86(s);
+#endif
+}