text: /*
   * 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 <string.h>
  #include <stdio.h>
  
  #include "common/attributes.h"
  #include "common/bitdepth.h"
  #include "common/dump.h"
  #include "common/intops.h"
  #include "common/mem.h"
  
  #include "src/cdef_apply.h"
  #include "src/ctx.h"
  #include "src/ipred_prepare.h"
  #include "src/lf_apply.h"
  #include "src/lr_apply.h"
  #include "src/recon.h"
  #include "src/scan.h"
  #include "src/tables.h"
  #include "src/wedge.h"
  
  static inline unsigned read_golomb(MsacContext *const msac) {
      int len = 0;
      unsigned val = 1;
  
      while (!dav1d_msac_decode_bool_equi(msac) && len < 32) len++;
      while (len--) val = (val << 1) + dav1d_msac_decode_bool_equi(msac);
  
      return val - 1;
  }
  
  static inline unsigned get_skip_ctx(const TxfmInfo *const t_dim,
                                      const enum BlockSize bs,
                                      const uint8_t *const a,
                                      const uint8_t *const l,
                                      const int chroma,
                                      const enum Dav1dPixelLayout layout)
  {
      const uint8_t *const b_dim = dav1d_block_dimensions[bs];
  
      if (chroma) {
          const int ss_ver = layout == DAV1D_PIXEL_LAYOUT_I420;
          const int ss_hor = layout != DAV1D_PIXEL_LAYOUT_I444;
          const int not_one_blk = b_dim[2] - (!!b_dim[2] && ss_hor) > t_dim->lw ||
                                  b_dim[3] - (!!b_dim[3] && ss_ver) > t_dim->lh;
          unsigned ca, cl;
  
  #define MERGE_CTX(dir, type, no_val) \
          c##dir = *(const type *) dir != no_val; \
          break
  
          switch (t_dim->lw) {
          /* For some reason the MSVC CRT _wassert() function is not flagged as
           * __declspec(noreturn), so when using those headers the compiler will
           * expect execution to continue after an assertion has been triggered
           * and will therefore complain about the use of uninitialized variables
           * when compiled in debug mode if we put the default case at the end. */
          default: assert(0); /* fall-through */
          case TX_4X4:   MERGE_CTX(a, uint8_t,  0x40);
          case TX_8X8:   MERGE_CTX(a, uint16_t, 0x4040);
          case TX_16X16: MERGE_CTX(a, uint32_t, 0x40404040U);
          case TX_32X32: MERGE_CTX(a, uint64_t, 0x4040404040404040ULL);
          }
          switch (t_dim->lh) {
          default: assert(0); /* fall-through */
          case TX_4X4:   MERGE_CTX(l, uint8_t,  0x40);
          case TX_8X8:   MERGE_CTX(l, uint16_t, 0x4040);
          case TX_16X16: MERGE_CTX(l, uint32_t, 0x40404040U);
          case TX_32X32: MERGE_CTX(l, uint64_t, 0x4040404040404040ULL);
          }
  #undef MERGE_CTX
  
          return 7 + not_one_blk * 3 + ca + cl;
      } else if (b_dim[2] == t_dim->lw && b_dim[3] == t_dim->lh) {
          return 0;
      } else {
          unsigned la, ll;
  
  #define MERGE_CTX(dir, type, tx) \
          if (tx == TX_64X64) { \
              uint64_t tmp = *(const uint64_t *) dir; \
              tmp |= *(const uint64_t *) &dir[8]; \
              l##dir = (unsigned) (tmp >> 32) | (unsigned) tmp; \
          } else \
              l##dir = *(const type *) dir; \
          if (tx == TX_32X32) l##dir |= *(const type *) &dir[sizeof(type)]; \
          if (tx >= TX_16X16) l##dir |= l##dir >> 16; \
          if (tx >= TX_8X8)   l##dir |= l##dir >> 8; \
          break
  
          switch (t_dim->lw) {
          default: assert(0); /* fall-through */
          case TX_4X4:   MERGE_CTX(a, uint8_t,  TX_4X4);
          case TX_8X8:   MERGE_CTX(a, uint16_t, TX_8X8);
          case TX_16X16: MERGE_CTX(a, uint32_t, TX_16X16);
          case TX_32X32: MERGE_CTX(a, uint32_t, TX_32X32);
          case TX_64X64: MERGE_CTX(a, uint32_t, TX_64X64);
          }
          switch (t_dim->lh) {
          default: assert(0); /* fall-through */
          case TX_4X4:   MERGE_CTX(l, uint8_t,  TX_4X4);
          case TX_8X8:   MERGE_CTX(l, uint16_t, TX_8X8);
          case TX_16X16: MERGE_CTX(l, uint32_t, TX_16X16);
          case TX_32X32: MERGE_CTX(l, uint32_t, TX_32X32);
          case TX_64X64: MERGE_CTX(l, uint32_t, TX_64X64);
          }
  #undef MERGE_CTX
  
          return dav1d_skip_ctx[umin(la & 0x3F, 4)][umin(ll & 0x3F, 4)];
      }
  }
  
  static inline unsigned get_dc_sign_ctx(const int /*enum RectTxfmSize*/ tx,
                                         const uint8_t *const a,
                                         const uint8_t *const l)
  {
      uint64_t mask = 0xC0C0C0C0C0C0C0C0ULL, mul = 0x0101010101010101ULL;
      int s;
  
  #if ARCH_X86_64 && defined(__GNUC__)
      /* Coerce compilers into producing better code. For some reason
       * every x86-64 compiler is awful at handling 64-bit constants. */
      __asm__("" : "+r"(mask), "+r"(mul));
  #endif
  
      switch(tx) {
      default: assert(0); /* fall-through */
      case TX_4X4: {
          int t = *(const uint8_t *) a >> 6;
          t    += *(const uint8_t *) l >> 6;
          s = t - 1 - 1;
          break;
      }
      case TX_8X8: {
          uint32_t t = *(const uint16_t *) a & (uint32_t) mask;
          t         += *(const uint16_t *) l & (uint32_t) mask;
          t *= 0x04040404U;
          s = (int) (t >> 24) - 2 - 2;
          break;
      }
      case TX_16X16: {
          uint32_t t = (*(const uint32_t *) a & (uint32_t) mask) >> 6;
          t         += (*(const uint32_t *) l & (uint32_t) mask) >> 6;
          t *= (uint32_t) mul;
          s = (int) (t >> 24) - 4 - 4;
          break;
      }
      case TX_32X32: {
          uint64_t t = (*(const uint64_t *) a & mask) >> 6;
          t         += (*(const uint64_t *) l & mask) >> 6;
          t *= mul;
          s = (int) (t >> 56) - 8 - 8;
          break;
      }
      case TX_64X64: {
          uint64_t t = (*(const uint64_t *) &a[0] & mask) >> 6;
          t         += (*(const uint64_t *) &a[8] & mask) >> 6;
          t         += (*(const uint64_t *) &l[0] & mask) >> 6;
          t         += (*(const uint64_t *) &l[8] & mask) >> 6;
          t *= mul;
          s = (int) (t >> 56) - 16 - 16;
          break;
      }
      case RTX_4X8: {
          uint32_t t = *(const uint8_t  *) a & (uint32_t) mask;
          t         += *(const uint16_t *) l & (uint32_t) mask;
          t *= 0x04040404U;
          s = (int) (t >> 24) - 1 - 2;
          break;
      }
      case RTX_8X4: {
          uint32_t t = *(const uint16_t *) a & (uint32_t) mask;
          t         += *(const uint8_t  *) l & (uint32_t) mask;
          t *= 0x04040404U;
          s = (int) (t >> 24) - 2 - 1;
          break;
      }
      case RTX_8X16: {
          uint32_t t = *(const uint16_t *) a & (uint32_t) mask;
          t         += *(const uint32_t *) l & (uint32_t) mask;
          t = (t >> 6) * (uint32_t) mul;
          s = (int) (t >> 24) - 2 - 4;
          break;
      }
      case RTX_16X8: {
          uint32_t t = *(const uint32_t *) a & (uint32_t) mask;
          t         += *(const uint16_t *) l & (uint32_t) mask;
          t = (t >> 6) * (uint32_t) mul;
          s = (int) (t >> 24) - 4 - 2;
          break;
      }
      case RTX_16X32: {
          uint64_t t = *(const uint32_t *) a & (uint32_t) mask;
          t         += *(const uint64_t *) l & mask;
          t = (t >> 6) * mul;
          s = (int) (t >> 56) - 4 - 8;
          break;
      }
      case RTX_32X16: {
          uint64_t t = *(const uint64_t *) a & mask;
          t         += *(const uint32_t *) l & (uint32_t) mask;
          t = (t >> 6) * mul;
          s = (int) (t >> 56) - 8 - 4;
          break;
      }
      case RTX_32X64: {
          uint64_t t = (*(const uint64_t *) &a[0] & mask) >> 6;
          t         += (*(const uint64_t *) &l[0] & mask) >> 6;
          t         += (*(const uint64_t *) &l[8] & mask) >> 6;
          t *= mul;
          s = (int) (t >> 56) - 8 - 16;
          break;
      }
      case RTX_64X32: {
          uint64_t t = (*(const uint64_t *) &a[0] & mask) >> 6;
          t         += (*(const uint64_t *) &a[8] & mask) >> 6;
          t         += (*(const uint64_t *) &l[0] & mask) >> 6;
          t *= mul;
          s = (int) (t >> 56) - 16 - 8;
          break;
      }
      case RTX_4X16: {
          uint32_t t = *(const uint8_t  *) a & (uint32_t) mask;
          t         += *(const uint32_t *) l & (uint32_t) mask;
          t = (t >> 6) * (uint32_t) mul;
          s = (int) (t >> 24) - 1 - 4;
          break;
      }
      case RTX_16X4: {
          uint32_t t = *(const uint32_t *) a & (uint32_t) mask;
          t         += *(const uint8_t  *) l & (uint32_t) mask;
          t = (t >> 6) * (uint32_t) mul;
          s = (int) (t >> 24) - 4 - 1;
          break;
      }
      case RTX_8X32: {
          uint64_t t = *(const uint16_t *) a & (uint32_t) mask;
          t         += *(const uint64_t *) l & mask;
          t = (t >> 6) * mul;
          s = (int) (t >> 56) - 2 - 8;
          break;
      }
      case RTX_32X8: {
          uint64_t t = *(const uint64_t *) a & mask;
          t         += *(const uint16_t *) l & (uint32_t) mask;
          t = (t >> 6) * mul;
          s = (int) (t >> 56) - 8 - 2;
          break;
      }
      case RTX_16X64: {
          uint64_t t = *(const uint32_t *) a & (uint32_t) mask;
          t         += *(const uint64_t *) &l[0] & mask;
          t = (t >> 6) + ((*(const uint64_t *) &l[8] & mask) >> 6);
          t *= mul;
          s = (int) (t >> 56) - 4 - 16;
          break;
      }
      case RTX_64X16: {
          uint64_t t = *(const uint64_t *) &a[0] & mask;
          t         += *(const uint32_t *) l & (uint32_t) mask;
          t = (t >> 6) + ((*(const uint64_t *) &a[8] & mask) >> 6);
          t *= mul;
          s = (int) (t >> 56) - 16 - 4;
          break;
      }
      }
  
      return (s != 0) + (s > 0);
  }
  
  static inline unsigned get_lo_ctx(const uint8_t *const levels,
                                    const enum TxClass tx_class,
                                    unsigned *const hi_mag,
                                    const uint8_t (*const ctx_offsets)[5],
                                    const unsigned x, const unsigned y,
                                    const ptrdiff_t stride)
  {
      unsigned mag = levels[0 * stride + 1] + levels[1 * stride + 0];
      unsigned offset;
      if (tx_class == TX_CLASS_2D) {
          mag += levels[1 * stride + 1];
          *hi_mag = mag;
          mag += levels[0 * stride + 2] + levels[2 * stride + 0];
          offset = ctx_offsets[umin(y, 4)][umin(x, 4)];
      } else {
          mag += levels[0 * stride + 2];
          *hi_mag = mag;
          mag += levels[0 * stride + 3] + levels[0 * stride + 4];
          offset = 26 + (y > 1 ? 10 : y * 5);
      }
      return offset + (mag > 512 ? 4 : (mag + 64) >> 7);
  }
  
  static int decode_coefs(Dav1dTileContext *const t,
                          uint8_t *const a, uint8_t *const l,
                          const enum RectTxfmSize tx, const enum BlockSize bs,
                          const Av1Block *const b, const int intra,
                          const int plane, coef *cf,
                          enum TxfmType *const txtp, uint8_t *res_ctx)
  {
      Dav1dTileState *const ts = t->ts;
      const int chroma = !!plane;
      const Dav1dFrameContext *const f = t->f;
      const int lossless = f->frame_hdr->segmentation.lossless[b->seg_id];
      const TxfmInfo *const t_dim = &dav1d_txfm_dimensions[tx];
      const int dbg = DEBUG_BLOCK_INFO && plane && 0;
  
      if (dbg)
          printf("Start: r=%d\n", ts->msac.rng);
  
      // does this block have any non-zero coefficients
      const int sctx = get_skip_ctx(t_dim, bs, a, l, chroma, f->cur.p.layout);
      const int all_skip = dav1d_msac_decode_bool_adapt(&ts->msac,
                               ts->cdf.coef.skip[t_dim->ctx][sctx]);
      if (dbg)
          printf("Post-non-zero[%d][%d][%d]: r=%d\n",
                 t_dim->ctx, sctx, all_skip, ts->msac.rng);
      if (all_skip) {
          *res_ctx = 0x40;
          *txtp = lossless * WHT_WHT; /* lossless ? WHT_WHT : DCT_DCT */
          return -1;
      }
  
      // transform type (chroma: derived, luma: explicitly coded)
      if (lossless) {
          assert(t_dim->max == TX_4X4);
          *txtp = WHT_WHT;
      } else if (t_dim->max + intra >= TX_64X64) {
          *txtp = DCT_DCT;
      } else if (chroma) {
          // inferred from either the luma txtp (inter) or a LUT (intra)
          *txtp = intra ? dav1d_txtp_from_uvmode[b->uv_mode] :
                          get_uv_inter_txtp(t_dim, *txtp);
      } else if (!f->frame_hdr->segmentation.qidx[b->seg_id]) {
          // In libaom, lossless is checked by a literal qidx == 0, but not all
          // such blocks are actually lossless. The remainder gets an implicit
          // transform type (for luma)
          *txtp = DCT_DCT;
      } else {
          unsigned idx;
          if (intra) {
              const enum IntraPredMode y_mode_nofilt = b->y_mode == FILTER_PRED ?
                  dav1d_filter_mode_to_y_mode[b->y_angle] : b->y_mode;
              if (f->frame_hdr->reduced_txtp_set || t_dim->min == TX_16X16) {
                  idx = dav1d_msac_decode_symbol_adapt4(&ts->msac,
                            ts->cdf.m.txtp_intra2[t_dim->min][y_mode_nofilt], 4);
                  *txtp = dav1d_tx_types_per_set[idx + 0];
              } else {
                  idx = dav1d_msac_decode_symbol_adapt8(&ts->msac,
                            ts->cdf.m.txtp_intra1[t_dim->min][y_mode_nofilt], 6);
                  *txtp = dav1d_tx_types_per_set[idx + 5];
              }
              if (dbg)
                  printf("Post-txtp-intra[%d->%d][%d][%d->%d]: r=%d\n",
                         tx, t_dim->min, y_mode_nofilt, idx, *txtp, ts->msac.rng);
          } else {
              if (f->frame_hdr->reduced_txtp_set || t_dim->max == TX_32X32) {
                  idx = dav1d_msac_decode_bool_adapt(&ts->msac,
                            ts->cdf.m.txtp_inter3[t_dim->min]);
                  *txtp = (idx - 1) & IDTX; /* idx ? DCT_DCT : IDTX */
              } else if (t_dim->min == TX_16X16) {
                  idx = dav1d_msac_decode_symbol_adapt16(&ts->msac,
                            ts->cdf.m.txtp_inter2, 11);
                  *txtp = dav1d_tx_types_per_set[idx + 12];
              } else {
                  idx = dav1d_msac_decode_symbol_adapt16(&ts->msac,
                            ts->cdf.m.txtp_inter1[t_dim->min], 15);
                  *txtp = dav1d_tx_types_per_set[idx + 24];
              }
              if (dbg)
                  printf("Post-txtp-inter[%d->%d][%d->%d]: r=%d\n",
                         tx, t_dim->min, idx, *txtp, ts->msac.rng);
          }
      }
  
      // find end-of-block (eob)
      int eob_bin;
      const int tx2dszctx = imin(t_dim->lw, TX_32X32) + imin(t_dim->lh, TX_32X32);
      const enum TxClass tx_class = dav1d_tx_type_class[*txtp];
      const int is_1d = tx_class != TX_CLASS_2D;
      switch (tx2dszctx) {
  #define case_sz(sz, bin, ns, is_1d) \
      case sz: { \
          uint16_t *const eob_bin_cdf = ts->cdf.coef.eob_bin_##bin[chroma]is_1d; \
          eob_bin = dav1d_msac_decode_symbol_adapt##ns(&ts->msac, eob_bin_cdf, 4 + sz); \
          break; \
      }
      case_sz(0,   16,  4, [is_1d]);
      case_sz(1,   32,  8, [is_1d]);
      case_sz(2,   64,  8, [is_1d]);
      case_sz(3,  128,  8, [is_1d]);
      case_sz(4,  256, 16, [is_1d]);
      case_sz(5,  512, 16,        );
      case_sz(6, 1024, 16,        );
  #undef case_sz
      }
      if (dbg)
          printf("Post-eob_bin_%d[%d][%d][%d]: r=%d\n",
                 16 << tx2dszctx, chroma, is_1d, eob_bin, ts->msac.rng);
      int eob;
      if (eob_bin > 1) {
          uint16_t *const eob_hi_bit_cdf =
              ts->cdf.coef.eob_hi_bit[t_dim->ctx][chroma][eob_bin];
          const int eob_hi_bit = dav1d_msac_decode_bool_adapt(&ts->msac, eob_hi_bit_cdf);
          if (dbg)
              printf("Post-eob_hi_bit[%d][%d][%d][%d]: r=%d\n",
                     t_dim->ctx, chroma, eob_bin, eob_hi_bit, ts->msac.rng);
          eob = ((eob_hi_bit | 2) << (eob_bin - 2)) |
                dav1d_msac_decode_bools(&ts->msac, eob_bin - 2);
          if (dbg)
              printf("Post-eob[%d]: r=%d\n", eob, ts->msac.rng);
      } else {
          eob = eob_bin;
      }
  
      // base tokens
      uint16_t (*const eob_cdf)[4] = ts->cdf.coef.eob_base_tok[t_dim->ctx][chroma];
      uint16_t (*const hi_cdf)[4] = ts->cdf.coef.br_tok[imin(t_dim->ctx, 3)][chroma];
      const uint16_t *const scan = dav1d_scans[tx][tx_class];
      int dc_tok;
  
      if (eob) {
          uint16_t (*const lo_cdf)[4] = ts->cdf.coef.base_tok[t_dim->ctx][chroma];
          uint8_t *const levels = t->scratch.levels; // bits 0-5: tok, 6-7: lo_tok
          const int sw = imin(t_dim->w, 8), sh = imin(t_dim->h, 8);
          const unsigned shift = 2 + imin(t_dim->lh, 3), mask = 4 * sh - 1;
  
          /* eob */
          unsigned rc = scan[eob], x = rc >> shift, y = rc & mask;
          unsigned ctx = 1 + (eob > sw * sh * 2) + (eob > sw * sh * 4);
          int eob_tok = dav1d_msac_decode_symbol_adapt4(&ts->msac, eob_cdf[ctx], 2);
          int tok = eob_tok + 1;
          int level_tok = tok * 0x41;
          unsigned mag;
          if (dbg)
              printf("Post-lo_tok[%d][%d][%d][%d=%d=%d]: r=%d\n",
                     t_dim->ctx, chroma, ctx, eob, rc, tok, ts->msac.rng);
  
  #define DECODE_COEFS_CLASS(tx_class) \
          if (eob_tok == 2) { \
              ctx = (tx_class == TX_CLASS_2D ? (x | y) > 1 : \
                     tx_class == TX_CLASS_H ? x != 0 : y != 0) ? 14 : 7; \
              tok = dav1d_msac_decode_hi_tok(&ts->msac, hi_cdf[ctx]); \
              level_tok = tok + (3 << 6); \
              if (dbg) \
                  printf("Post-hi_tok[%d][%d][%d][%d=%d=%d]: r=%d\n", \
                         imin(t_dim->ctx, 3), chroma, ctx, eob, rc, tok, \
                         ts->msac.rng); \
          } \
          cf[rc] = tok; \
          if (tx_class == TX_CLASS_H) \
              /* Transposing reduces the stride and padding requirements */ \
              levels[y * stride + x] = (uint8_t) level_tok; \
          else \
              levels[x * stride + y] = (uint8_t) level_tok; \
          for (int i = eob - 1; i > 0; i--) { /* ac */ \
              if (tx_class == TX_CLASS_H) \
                  rc = i, x = rc & mask, y = rc >> shift; \
              else \
                  rc = scan[i], x = rc >> shift, y = rc & mask; \
              assert(x < 32 && y < 32); \
              uint8_t *const level = levels + x * stride + y; \
              ctx = get_lo_ctx(level, tx_class, &mag, lo_ctx_offsets, x, y, stride); \
              if (tx_class == TX_CLASS_2D) \
                  y |= x; \
              tok = dav1d_msac_decode_symbol_adapt4(&ts->msac, lo_cdf[ctx], 3); \
              level_tok = tok * 0x41; \
              if (dbg) \
                  printf("Post-lo_tok[%d][%d][%d][%d=%d=%d]: r=%d\n", \
                         t_dim->ctx, chroma, ctx, i, rc, tok, ts->msac.rng); \
              if (tok == 3) { \
                  mag &= 63; \
                  ctx = (y > (tx_class == TX_CLASS_2D) ? 14 : 7) + \
                        (mag > 12 ? 6 : (mag + 1) >> 1); \
                  tok = dav1d_msac_decode_hi_tok(&ts->msac, hi_cdf[ctx]); \
                  level_tok = tok + (3 << 6); \
                  if (dbg) \
                      printf("Post-hi_tok[%d][%d][%d][%d=%d=%d]: r=%d\n", \
                             imin(t_dim->ctx, 3), chroma, ctx, i, rc, tok, \
                             ts->msac.rng); \
              } \
              cf[rc] = tok; \
              *level = (uint8_t) level_tok; \
          } \
          /* dc */ \
          ctx = (tx_class == TX_CLASS_2D) ? 0 : \
              get_lo_ctx(levels, tx_class, &mag, lo_ctx_offsets, 0, 0, stride); \
          dc_tok = dav1d_msac_decode_symbol_adapt4(&ts->msac, lo_cdf[ctx], 3); \
          if (dbg) \
              printf("Post-dc_lo_tok[%d][%d][%d][%d]: r=%d\n", \
                     t_dim->ctx, chroma, ctx, dc_tok, ts->msac.rng); \
          if (dc_tok == 3) { \
              if (tx_class == TX_CLASS_2D) \
                  mag = levels[0 * stride + 1] + levels[1 * stride + 0] + \
                        levels[1 * stride + 1]; \
              mag &= 63; \
              ctx = mag > 12 ? 6 : (mag + 1) >> 1; \
              dc_tok = dav1d_msac_decode_hi_tok(&ts->msac, hi_cdf[ctx]); \
              if (dbg) \
                  printf("Post-dc_hi_tok[%d][%d][0][%d]: r=%d\n", \
                         imin(t_dim->ctx, 3), chroma, dc_tok, ts->msac.rng); \
          } \
          break
  
          switch (tx_class) {
          case TX_CLASS_2D: {
              const unsigned nonsquare_tx = tx >= RTX_4X8;
              const uint8_t (*const lo_ctx_offsets)[5] =
                  dav1d_lo_ctx_offsets[nonsquare_tx + (tx & nonsquare_tx)];
              const ptrdiff_t stride = 4 * sh;
              memset(levels, 0, stride * (4 * sw + 2));
              DECODE_COEFS_CLASS(TX_CLASS_2D);
          }
          case TX_CLASS_H: {
  #define lo_ctx_offsets NULL
              const ptrdiff_t stride = 16;
              memset(levels, 0, stride * (4 * sh + 2));
              DECODE_COEFS_CLASS(TX_CLASS_H);
          }
          case TX_CLASS_V: {
              const ptrdiff_t stride = 16;
              memset(levels, 0, stride * (4 * sw + 2));
              DECODE_COEFS_CLASS(TX_CLASS_V);
          }
  #undef lo_ctx_offsets
  #undef DECODE_COEFS_CLASS
          default: assert(0);
          }
      } else { // dc-only
          int tok_br = dav1d_msac_decode_symbol_adapt4(&ts->msac, eob_cdf[0], 2);
          dc_tok = 1 + tok_br;
          if (dbg)
              printf("Post-dc_lo_tok[%d][%d][%d][%d]: r=%d\n",
                     t_dim->ctx, chroma, 0, dc_tok, ts->msac.rng);
          if (tok_br == 2) {
              dc_tok = dav1d_msac_decode_hi_tok(&ts->msac, hi_cdf[0]);
              if (dbg)
                  printf("Post-dc_hi_tok[%d][%d][0][%d]: r=%d\n",
                         imin(t_dim->ctx, 3), chroma, dc_tok, ts->msac.rng);
          }
      }
  
      // residual and sign
      int dc_sign = 1 << 6;
      const uint16_t *const dq_tbl = ts->dq[b->seg_id][plane];
      const uint8_t *const qm_tbl = f->qm[lossless || is_1d || *txtp == IDTX][tx][plane];
      const int dq_shift = imax(0, t_dim->ctx - 2);
      const int bitdepth = BITDEPTH == 8 ? 8 : f->cur.p.bpc;
      const int cf_max = (1 << (7 + bitdepth)) - 1;
      unsigned cul_level = 0;
  
      if (dc_tok) { // dc
          const int dc_sign_ctx = get_dc_sign_ctx(tx, a, l);
          uint16_t *const dc_sign_cdf =
              ts->cdf.coef.dc_sign[chroma][dc_sign_ctx];
          const int sign = dav1d_msac_decode_bool_adapt(&ts->msac, dc_sign_cdf);
          const unsigned dq = (dq_tbl[0] * qm_tbl[0] + 16) >> 5;
          if (dbg)
              printf("Post-dc_sign[%d][%d][%d]: r=%d\n",
                     chroma, dc_sign_ctx, sign, ts->msac.rng);
          dc_sign = (sign - 1) & (2 << 6);
  
          if (dc_tok == 15) {
              dc_tok += read_golomb(&ts->msac);
              if (dbg)
                  printf("Post-dc_residual[%d->%d]: r=%d\n",
                         dc_tok - 15, dc_tok, ts->msac.rng);
  
              dc_tok &= 0xfffff;
          }
  
          cul_level += dc_tok;
          dc_tok = ((dq * dc_tok) & 0xffffff) >> dq_shift;
          cf[0] = imin(dc_tok - sign, cf_max) ^ -sign;
      }
      for (int i = 1; i <= eob; i++) { // ac
          const int rc = scan[i];
          int tok = cf[rc];
          if (!tok) continue;
  
          // sign
          const int sign = dav1d_msac_decode_bool_equi(&ts->msac);
          const unsigned dq = (dq_tbl[1] * qm_tbl[rc] + 16) >> 5;
          if (dbg)
              printf("Post-sign[%d=%d=%d]: r=%d\n", i, rc, sign, ts->msac.rng);
  
          // residual
          if (tok == 15) {
              tok += read_golomb(&ts->msac);
              if (dbg)
                  printf("Post-residual[%d=%d=%d->%d]: r=%d\n",
                         i, rc, tok - 15, tok, ts->msac.rng);
  
              // coefficient parsing, see 5.11.39
              tok &= 0xfffff;
          }
  
          // dequant, see 7.12.3
          cul_level += tok;
          tok = ((dq * tok) & 0xffffff) >> dq_shift;
          cf[rc] = imin(tok - sign, cf_max) ^ -sign;
      }
  
      // context
      *res_ctx = umin(cul_level, 63) | dc_sign;
  
      return eob;
  }
  
  static void read_coef_tree(Dav1dTileContext *const t,
                             const enum BlockSize bs, const Av1Block *const b,
                             const enum RectTxfmSize ytx, const int depth,
                             const uint16_t *const tx_split,
                             const int x_off, const int y_off, pixel *dst)
  {
      const Dav1dFrameContext *const f = t->f;
      Dav1dTileState *const ts = t->ts;
      const Dav1dDSPContext *const dsp = f->dsp;
      const TxfmInfo *const t_dim = &dav1d_txfm_dimensions[ytx];
      const int txw = t_dim->w, txh = t_dim->h;
  
      /* y_off can be larger than 3 since lossless blocks use TX_4X4 but can't
       * be splitted. Aviods an undefined left shift. */
      if (depth < 2 && tx_split[depth] &&
          tx_split[depth] & (1 << (y_off * 4 + x_off)))
      {
          const enum RectTxfmSize sub = t_dim->sub;
          const TxfmInfo *const sub_t_dim = &dav1d_txfm_dimensions[sub];
          const int txsw = sub_t_dim->w, txsh = sub_t_dim->h;
  
          read_coef_tree(t, bs, b, sub, depth + 1, tx_split,
                         x_off * 2 + 0, y_off * 2 + 0, dst);
          t->bx += txsw;
          if (txw >= txh && t->bx < f->bw)
              read_coef_tree(t, bs, b, sub, depth + 1, tx_split, x_off * 2 + 1,
                             y_off * 2 + 0, dst ? &dst[4 * txsw] : NULL);
          t->bx -= txsw;
          t->by += txsh;
          if (txh >= txw && t->by < f->bh) {
              if (dst)
                  dst += 4 * txsh * PXSTRIDE(f->cur.stride[0]);
              read_coef_tree(t, bs, b, sub, depth + 1, tx_split,
                             x_off * 2 + 0, y_off * 2 + 1, dst);
              t->bx += txsw;
              if (txw >= txh && t->bx < f->bw)
                  read_coef_tree(t, bs, b, sub, depth + 1, tx_split, x_off * 2 + 1,
                                 y_off * 2 + 1, dst ? &dst[4 * txsw] : NULL);
              t->bx -= txsw;
          }
          t->by -= txsh;
      } else {
          const int bx4 = t->bx & 31, by4 = t->by & 31;
          enum TxfmType txtp;
          uint8_t cf_ctx;
          int eob;
          coef *cf;
          struct CodedBlockInfo *cbi;
  
          if (f->frame_thread.pass) {
              assert(ts->frame_thread.cf);
              cf = ts->frame_thread.cf;
              ts->frame_thread.cf += imin(t_dim->w, 8) * imin(t_dim->h, 8) * 16;
              cbi = &f->frame_thread.cbi[t->by * f->b4_stride + t->bx];
          } else {
              cf = bitfn(t->cf);
          }
          if (f->frame_thread.pass != 2) {
              eob = decode_coefs(t, &t->a->lcoef[bx4], &t->l.lcoef[by4],
                                 ytx, bs, b, 0, 0, cf, &txtp, &cf_ctx);
              if (DEBUG_BLOCK_INFO)
                  printf("Post-y-cf-blk[tx=%d,txtp=%d,eob=%d]: r=%d\n",
                         ytx, txtp, eob, ts->msac.rng);
  #define set_ctx(type, dir, diridx, off, mul, rep_macro) \
              rep_macro(type, t->dir lcoef, off, mul * cf_ctx)
  #define default_memset(dir, diridx, off, sz) \
              memset(&t->dir lcoef[off], cf_ctx, sz)
              case_set_upto16_with_default(imin(txh, f->bh - t->by), l., 1, by4);
              case_set_upto16_with_default(imin(txw, f->bw - t->bx), a->, 0, bx4);
  #undef default_memset
  #undef set_ctx
  #define set_ctx(type, dir, diridx, off, mul, rep_macro) \
              for (int y = 0; y < txh; y++) { \
                  rep_macro(type, txtp_map, 0, mul * txtp); \
                  txtp_map += 32; \
              }
              uint8_t *txtp_map = &t->txtp_map[by4 * 32 + bx4];
              case_set_upto16(txw,,,);
  #undef set_ctx
              if (f->frame_thread.pass == 1) {
                  cbi->eob[0] = eob;
                  cbi->txtp[0] = txtp;
              }
          } else {
              eob = cbi->eob[0];
              txtp = cbi->txtp[0];
          }
          if (!(f->frame_thread.pass & 1)) {
              assert(dst);
              if (eob >= 0) {
                  if (DEBUG_BLOCK_INFO && DEBUG_B_PIXELS)
                      coef_dump(cf, imin(t_dim->h, 8) * 4, imin(t_dim->w, 8) * 4, 3, "dq");
                  dsp->itx.itxfm_add[ytx][txtp](dst, f->cur.stride[0], cf, eob
                                                HIGHBD_CALL_SUFFIX);
                  if (DEBUG_BLOCK_INFO && DEBUG_B_PIXELS)
                      hex_dump(dst, f->cur.stride[0], t_dim->w * 4, t_dim->h * 4, "recon");
              }
          }
      }
  }
  
  void bytefn(dav1d_read_coef_blocks)(Dav1dTileContext *const t,
                                      const enum BlockSize bs, const Av1Block *const b)
  {
      const Dav1dFrameContext *const f = t->f;
      const int ss_ver = f->cur.p.layout == DAV1D_PIXEL_LAYOUT_I420;
      const int ss_hor = f->cur.p.layout != DAV1D_PIXEL_LAYOUT_I444;
      const int bx4 = t->bx & 31, by4 = t->by & 31;
      const int cbx4 = bx4 >> ss_hor, cby4 = by4 >> ss_ver;
      const uint8_t *const b_dim = dav1d_block_dimensions[bs];
      const int bw4 = b_dim[0], bh4 = b_dim[1];
      const int cbw4 = (bw4 + ss_hor) >> ss_hor, cbh4 = (bh4 + ss_ver) >> ss_ver;
      const int has_chroma = f->cur.p.layout != DAV1D_PIXEL_LAYOUT_I400 &&
                             (bw4 > ss_hor || t->bx & 1) &&
                             (bh4 > ss_ver || t->by & 1);
  
      if (b->skip) {
  #define set_ctx(type, dir, diridx, off, mul, rep_macro) \
          rep_macro(type, t->dir lcoef, off, mul * 0x40)
          case_set(bh4, l., 1, by4);
          case_set(bw4, a->, 0, bx4);
  #undef set_ctx
          if (has_chroma) {
  #define set_ctx(type, dir, diridx, off, mul, rep_macro) \
              rep_macro(type, t->dir ccoef[0], off, mul * 0x40); \
              rep_macro(type, t->dir ccoef[1], off, mul * 0x40)
              case_set(cbh4, l., 1, cby4);
              case_set(cbw4, a->, 0, cbx4);
  #undef set_ctx
          }
          return;
      }
  
      Dav1dTileState *const ts = t->ts;
      const int w4 = imin(bw4, f->bw - t->bx), h4 = imin(bh4, f->bh - t->by);
      const int cw4 = (w4 + ss_hor) >> ss_hor, ch4 = (h4 + ss_ver) >> ss_ver;
      assert(f->frame_thread.pass == 1);
      assert(!b->skip);
      const TxfmInfo *const uv_t_dim = &dav1d_txfm_dimensions[b->uvtx];
      const TxfmInfo *const t_dim = &dav1d_txfm_dimensions[b->intra ? b->tx : b->max_ytx];
  
      for (int init_y = 0; init_y < h4; init_y += 16) {
          for (int init_x = 0; init_x < w4; init_x += 16) {
              const int sub_h4 = imin(h4, 16 + init_y);
              const int sub_w4 = imin(w4, init_x + 16);
              int y_off = !!init_y, y, x;
              for (y = init_y, t->by += init_y; y < sub_h4;
                   y += t_dim->h, t->by += t_dim->h, y_off++)
              {
                  struct CodedBlockInfo *const cbi =
                      &f->frame_thread.cbi[t->by * f->b4_stride];
                  int x_off = !!init_x;
                  for (x = init_x, t->bx += init_x; x < sub_w4;
                       x += t_dim->w, t->bx += t_dim->w, x_off++)
                  {
                      if (!b->intra) {
                          read_coef_tree(t, bs, b, b->max_ytx, 0, b->tx_split,
                                         x_off, y_off, NULL);
                      } else {
                          uint8_t cf_ctx = 0x40;
                          enum TxfmType txtp;
                          const int eob = cbi[t->bx].eob[0] =
                              decode_coefs(t, &t->a->lcoef[bx4 + x],
                                           &t->l.lcoef[by4 + y], b->tx, bs, b, 1,
                                           0, ts->frame_thread.cf, &txtp, &cf_ctx);
                          if (DEBUG_BLOCK_INFO)
                              printf("Post-y-cf-blk[tx=%d,txtp=%d,eob=%d]: r=%d\n",
                                     b->tx, txtp, eob, ts->msac.rng);
                          cbi[t->bx].txtp[0] = txtp;
                          ts->frame_thread.cf += imin(t_dim->w, 8) * imin(t_dim->h, 8) * 16;
  #define set_ctx(type, dir, diridx, off, mul, rep_macro) \
                          rep_macro(type, t->dir lcoef, off, mul * cf_ctx)
  #define default_memset(dir, diridx, off, sz) \
                          memset(&t->dir lcoef[off], cf_ctx, sz)
                          case_set_upto16_with_default(imin(t_dim->h, f->bh - t->by),
                                                       l., 1, by4 + y);
                          case_set_upto16_with_default(imin(t_dim->w, f->bw - t->bx),
                                                       a->, 0, bx4 + x);
  #undef default_memset
  #undef set_ctx
                      }
                  }
                  t->bx -= x;
              }
              t->by -= y;
  
              if (!has_chroma) continue;
  
              const int sub_ch4 = imin(ch4, (init_y + 16) >> ss_ver);
              const int sub_cw4 = imin(cw4, (init_x + 16) >> ss_hor);
              for (int pl = 0; pl < 2; pl++) {
                  for (y = init_y >> ss_ver, t->by += init_y; y < sub_ch4;
                       y += uv_t_dim->h, t->by += uv_t_dim->h << ss_ver)
                  {
                      struct CodedBlockInfo *const cbi =
                          &f->frame_thread.cbi[t->by * f->b4_stride];
                      for (x = init_x >> ss_hor, t->bx += init_x; x < sub_cw4;
                           x += uv_t_dim->w, t->bx += uv_t_dim->w << ss_hor)
                      {
                          uint8_t cf_ctx = 0x40;
                          enum TxfmType txtp;
                          if (!b->intra)
                              txtp = t->txtp_map[(by4 + (y << ss_ver)) * 32 +
                                                  bx4 + (x << ss_hor)];
                          const int eob = cbi[t->bx].eob[1 + pl] =
                              decode_coefs(t, &t->a->ccoef[pl][cbx4 + x],
                                           &t->l.ccoef[pl][cby4 + y], b->uvtx, bs,
                                           b, b->intra, 1 + pl, ts->frame_thread.cf,
                                           &txtp, &cf_ctx);
                          if (DEBUG_BLOCK_INFO)
                              printf("Post-uv-cf-blk[pl=%d,tx=%d,"
                                     "txtp=%d,eob=%d]: r=%d\n",
                                     pl, b->uvtx, txtp, eob, ts->msac.rng);
                          cbi[t->bx].txtp[1 + pl] = txtp;
                          ts->frame_thread.cf += uv_t_dim->w * uv_t_dim->h * 16;
  #define set_ctx(type, dir, diridx, off, mul, rep_macro) \
                          rep_macro(type, t->dir ccoef[pl], off, mul * cf_ctx)
  #define default_memset(dir, diridx, off, sz) \
                          memset(&t->dir ccoef[pl][off], cf_ctx, sz)
                          case_set_upto16_with_default( \
                                   imin(uv_t_dim->h, (f->bh - t->by + ss_ver) >> ss_ver),
                                   l., 1, cby4 + y);
                          case_set_upto16_with_default( \
                                   imin(uv_t_dim->w, (f->bw - t->bx + ss_hor) >> ss_hor),
                                   a->, 0, cbx4 + x);
  #undef default_memset
  #undef set_ctx
                      }
                      t->bx -= x << ss_hor;
                  }
                  t->by -= y << ss_ver;
              }
          }
      }
  }
  
  static int mc(Dav1dTileContext *const t,
                pixel *const dst8, int16_t *const dst16, const ptrdiff_t dst_stride,
                const int bw4, const int bh4,
                const int bx, const int by, const int pl,
                const mv mv, const Dav1dThreadPicture *const refp, const int refidx,
                const enum Filter2d filter_2d)
  {
      assert((dst8 != NULL) ^ (dst16 != NULL));
      const Dav1dFrameContext *const f = t->f;
      const int ss_ver = !!pl && f->cur.p.layout == DAV1D_PIXEL_LAYOUT_I420;
      const int ss_hor = !!pl && f->cur.p.layout != DAV1D_PIXEL_LAYOUT_I444;
      const int h_mul = 4 >> ss_hor, v_mul = 4 >> ss_ver;
      const int mvx = mv.x, mvy = mv.y;
      const int mx = mvx & (15 >> !ss_hor), my = mvy & (15 >> !ss_ver);
      ptrdiff_t ref_stride = refp->p.stride[!!pl];
      const pixel *ref;
  
      if (refp->p.p.w == f->cur.p.w && refp->p.p.h == f->cur.p.h) {
          const int dx = bx * h_mul + (mvx >> (3 + ss_hor));
          const int dy = by * v_mul + (mvy >> (3 + ss_ver));
          int w, h;
  
          if (refp->p.data[0] != f->cur.data[0]) { // i.e. not for intrabc
              if (dav1d_thread_picture_wait(refp, dy + bh4 * v_mul + !!my * 4,
                                            PLANE_TYPE_Y + !!pl))
              {
                  return -1;
              }
              w = (f->cur.p.w + ss_hor) >> ss_hor;
              h = (f->cur.p.h + ss_ver) >> ss_ver;
          } else {
              w = f->bw * 4 >> ss_hor;
              h = f->bh * 4 >> ss_ver;
          }
          if (dx < !!mx * 3 || dy < !!my * 3 ||
              dx + bw4 * h_mul + !!mx * 4 > w ||
              dy + bh4 * v_mul + !!my * 4 > h)
          {
              pixel *const emu_edge_buf = bitfn(t->scratch.emu_edge);
              f->dsp->mc.emu_edge(bw4 * h_mul + !!mx * 7, bh4 * v_mul + !!my * 7,
                                  w, h, dx - !!mx * 3, dy - !!my * 3,
                                  emu_edge_buf, 192 * sizeof(pixel),
                                  refp->p.data[pl], ref_stride);
              ref = &emu_edge_buf[192 * !!my * 3 + !!mx * 3];
              ref_stride = 192 * sizeof(pixel);
          } else {
              ref = ((pixel *) refp->p.data[pl]) + PXSTRIDE(ref_stride) * dy + dx;
          }
  
          if (dst8 != NULL) {
              f->dsp->mc.mc[filter_2d](dst8, dst_stride, ref, ref_stride, bw4 * h_mul,
                                       bh4 * v_mul, mx << !ss_hor, my << !ss_ver
                                       HIGHBD_CALL_SUFFIX);
          } else {
              f->dsp->mc.mct[filter_2d](dst16, ref, ref_stride, bw4 * h_mul,
                                        bh4 * v_mul, mx << !ss_hor, my << !ss_ver
                                        HIGHBD_CALL_SUFFIX);
          }
      } else {
          assert(refp != &f->sr_cur);
  
          int orig_pos_y = (by * v_mul << 4) + mvy * (1 << !ss_ver);
          int orig_pos_x = (bx * h_mul << 4) + mvx * (1 << !ss_hor);
  #define scale_mv(res, val, scale) do { \
              const int64_t tmp = (int64_t)(val) * scale + (scale - 0x4000) * 8; \
              res = apply_sign64((int) ((llabs(tmp) + 128) >> 8), tmp) + 32;     \
          } while (0)
          int pos_y, pos_x;
          scale_mv(pos_x, orig_pos_x, f->svc[refidx][0].scale);
          scale_mv(pos_y, orig_pos_y, f->svc[refidx][1].scale);
  #undef scale_mv
          const int left = pos_x >> 10;
          const int top = pos_y >> 10;
          const int right =
              ((pos_x + (bw4 * h_mul - 1) * f->svc[refidx][0].step) >> 10) + 1;
          const int bottom =
              ((pos_y + (bh4 * v_mul - 1) * f->svc[refidx][1].step) >> 10) + 1;
  
          if (dav1d_thread_picture_wait(refp, bottom + 4, PLANE_TYPE_Y + !!pl))
              return -1;
          if (DEBUG_BLOCK_INFO)
              printf("Off %dx%d [%d,%d,%d], size %dx%d [%d,%d]\n",
                     left, top, orig_pos_x, f->svc[refidx][0].scale, refidx,
                     right-left, bottom-top,
                     f->svc[refidx][0].step, f->svc[refidx][1].step);
  
          const int w = (refp->p.p.w + ss_hor) >> ss_hor;
          const int h = (refp->p.p.h + ss_ver) >> ss_ver;
          if (left < 3 || top < 3 || right + 4 > w || bottom + 4 > h) {
              pixel *const emu_edge_buf = bitfn(t->scratch.emu_edge);
              f->dsp->mc.emu_edge(right - left + 7, bottom - top + 7,
                                  w, h, left - 3, top - 3,
                                  emu_edge_buf, 320 * sizeof(pixel),
                                  refp->p.data[pl], ref_stride);
              ref = &emu_edge_buf[320 * 3 + 3];
              ref_stride = 320 * sizeof(pixel);
              if (DEBUG_BLOCK_INFO) printf("Emu\n");
          } else {
              ref = ((pixel *) refp->p.data[pl]) + PXSTRIDE(ref_stride) * top + left;
          }
  
          if (dst8 != NULL) {
              f->dsp->mc.mc_scaled[filter_2d](dst8, dst_stride, ref, ref_stride,
                                              bw4 * h_mul, bh4 * v_mul,
                                              pos_x & 0x3ff, pos_y & 0x3ff,
                                              f->svc[refidx][0].step,
                                              f->svc[refidx][1].step
                                              HIGHBD_CALL_SUFFIX);
          } else {
              f->dsp->mc.mct_scaled[filter_2d](dst16, ref, ref_stride,
                                               bw4 * h_mul, bh4 * v_mul,
                                               pos_x & 0x3ff, pos_y & 0x3ff,
                                               f->svc[refidx][0].step,
                                               f->svc[refidx][1].step
                                               HIGHBD_CALL_SUFFIX);
          }
      }
  
      return 0;
  }
  
  static int obmc(Dav1dTileContext *const t,
                  pixel *const dst, const ptrdiff_t dst_stride,
                  const uint8_t *const b_dim, const int pl,
                  const int bx4, const int by4, const int w4, const int h4)
  {
      assert(!(t->bx & 1) && !(t->by & 1));
      const Dav1dFrameContext *const f = t->f;
      const refmvs *const r = &f->mvs[t->by * f->b4_stride + t->bx];
      pixel *const lap = bitfn(t->scratch.lap);
      const int ss_ver = !!pl && f->cur.p.layout == DAV1D_PIXEL_LAYOUT_I420;
      const int ss_hor = !!pl && f->cur.p.layout != DAV1D_PIXEL_LAYOUT_I444;
      const int h_mul = 4 >> ss_hor, v_mul = 4 >> ss_ver;
      int res;
  
      if (t->by > t->ts->tiling.row_start &&
          (!pl || b_dim[0] * h_mul + b_dim[1] * v_mul >= 16))
      {
          for (int i = 0, x = 0; x < w4 && i < imin(b_dim[2], 4); ) {
              // only odd blocks are considered for overlap handling, hence +1
              const refmvs *const a_r = &r[x - f->b4_stride + 1];
              const uint8_t *const a_b_dim =
                  dav1d_block_dimensions[dav1d_sbtype_to_bs[a_r->sb_type]];
  
              if (a_r->ref[0] > 0) {
                  const int ow4 = iclip(a_b_dim[0], 2, b_dim[0]);
                  const int oh4 = imin(b_dim[1], 16) >> 1;
                  res = mc(t, lap, NULL, ow4 * h_mul * sizeof(pixel), ow4, (oh4 * 3 + 3) >> 2,
                           t->bx + x, t->by, pl, a_r->mv[0],
                           &f->refp[a_r->ref[0] - 1], a_r->ref[0] - 1,
                           dav1d_filter_2d[t->a->filter[1][bx4 + x + 1]][t->a->filter[0][bx4 + x + 1]]);
                  if (res) return res;
                  f->dsp->mc.blend_h(&dst[x * h_mul], dst_stride, lap,
                                     h_mul * ow4, v_mul * oh4);
                  i++;
              }
              x += imax(a_b_dim[0], 2);
          }
      }
  
      if (t->bx > t->ts->tiling.col_start)
          for (int i = 0, y = 0; y < h4 && i < imin(b_dim[3], 4); ) {
              // only odd blocks are considered for overlap handling, hence +1
              const refmvs *const l_r = &r[(y + 1) * f->b4_stride - 1];
              const uint8_t *const l_b_dim =
                  dav1d_block_dimensions[dav1d_sbtype_to_bs[l_r->sb_type]];
  
              if (l_r->ref[0] > 0) {
                  const int ow4 = imin(b_dim[0], 16) >> 1;
                  const int oh4 = iclip(l_b_dim[1], 2, b_dim[1]);
                  res = mc(t, lap, NULL, h_mul * ow4 * sizeof(pixel), ow4, oh4,
                           t->bx, t->by + y, pl, l_r->mv[0],
                           &f->refp[l_r->ref[0] - 1], l_r->ref[0] - 1,
                           dav1d_filter_2d[t->l.filter[1][by4 + y + 1]][t->l.filter[0][by4 + y + 1]]);
                  if (res) return res;
                  f->dsp->mc.blend_v(&dst[y * v_mul * PXSTRIDE(dst_stride)],
                                     dst_stride, lap, h_mul * ow4, v_mul * oh4);
                  i++;
              }
              y += imax(l_b_dim[1], 2);
          }
      return 0;
  }
  
  static int warp_affine(Dav1dTileContext *const t,
                         pixel *dst8, int16_t *dst16, const ptrdiff_t dstride,
                         const uint8_t *const b_dim, const int pl,
                         const Dav1dThreadPicture *const refp,
                         const Dav1dWarpedMotionParams *const wmp)
  {
      assert((dst8 != NULL) ^ (dst16 != NULL));
      const Dav1dFrameContext *const f = t->f;
      const Dav1dDSPContext *const dsp = f->dsp;
      const int ss_ver = !!pl && f->cur.p.layout == DAV1D_PIXEL_LAYOUT_I420;
      const int ss_hor = !!pl && f->cur.p.layout != DAV1D_PIXEL_LAYOUT_I444;
      const int h_mul = 4 >> ss_hor, v_mul = 4 >> ss_ver;
      assert(!((b_dim[0] * h_mul) & 7) && !((b_dim[1] * v_mul) & 7));
      const int32_t *const mat = wmp->matrix;
      const int width = (refp->p.p.w + ss_hor) >> ss_hor;
      const int height = (refp->p.p.h + ss_ver) >> ss_ver;
  
      for (int y = 0; y < b_dim[1] * v_mul; y += 8) {
          for (int x = 0; x < b_dim[0] * h_mul; x += 8) {
              // calculate transformation relative to center of 8x8 block in
              // luma pixel units
              const int src_x = t->bx * 4 + ((x + 4) << ss_hor);
              const int src_y = t->by * 4 + ((y + 4) << ss_ver);
              const int64_t mvx = ((int64_t) mat[2] * src_x +
                                   (int64_t) mat[3] * src_y + mat[0]) >> ss_hor;
              const int64_t mvy = ((int64_t) mat[4] * src_x +
                                   (int64_t) mat[5] * src_y + mat[1]) >> ss_ver;
  
              const int dx = (int) (mvx >> 16) - 4;
              const int mx = (((int) mvx & 0xffff) - wmp->alpha * 4 -
                                                     wmp->beta  * 7) & ~0x3f;
              const int dy = (int) (mvy >> 16) - 4;
              const int my = (((int) mvy & 0xffff) - wmp->gamma * 4 -
                                                     wmp->delta * 4) & ~0x3f;
  
              const pixel *ref_ptr;
              ptrdiff_t ref_stride = refp->p.stride[!!pl];
  
              if (dav1d_thread_picture_wait(refp, dy + 4 + 8,
                                            PLANE_TYPE_Y + !!pl))
              {
                  return -1;
              }
              if (dx < 3 || dx + 8 + 4 > width || dy < 3 || dy + 8 + 4 > height) {
                  pixel *const emu_edge_buf = bitfn(t->scratch.emu_edge);
                  f->dsp->mc.emu_edge(15, 15, width, height, dx - 3, dy - 3,
                                      emu_edge_buf, 32 * sizeof(pixel),
                                      refp->p.data[pl], ref_stride);
                  ref_ptr = &emu_edge_buf[32 * 3 + 3];
                  ref_stride = 32 * sizeof(pixel);
              } else {
                  ref_ptr = ((pixel *) refp->p.data[pl]) + PXSTRIDE(ref_stride) * dy + dx;
              }
              if (dst16 != NULL)
                  dsp->mc.warp8x8t(&dst16[x], dstride, ref_ptr, ref_stride,
                                   wmp->abcd, mx, my HIGHBD_CALL_SUFFIX);
              else
                  dsp->mc.warp8x8(&dst8[x], dstride, ref_ptr, ref_stride,
                                  wmp->abcd, mx, my HIGHBD_CALL_SUFFIX);
          }
          if (dst8) dst8  += 8 * PXSTRIDE(dstride);
          else      dst16 += 8 * dstride;
      }
      return 0;
  }
  
  void bytefn(dav1d_recon_b_intra)(Dav1dTileContext *const t, const enum BlockSize bs,
                                   const enum EdgeFlags intra_edge_flags,
                                   const Av1Block *const b)
  {
      Dav1dTileState *const ts = t->ts;
      const Dav1dFrameContext *const f = t->f;
      const Dav1dDSPContext *const dsp = f->dsp;
      const int bx4 = t->bx & 31, by4 = t->by & 31;
      const int ss_ver = f->cur.p.layout == DAV1D_PIXEL_LAYOUT_I420;
      const int ss_hor = f->cur.p.layout != DAV1D_PIXEL_LAYOUT_I444;
      const int cbx4 = bx4 >> ss_hor, cby4 = by4 >> ss_ver;
      const uint8_t *const b_dim = dav1d_block_dimensions[bs];
      const int bw4 = b_dim[0], bh4 = b_dim[1];
      const int w4 = imin(bw4, f->bw - t->bx), h4 = imin(bh4, f->bh - t->by);
      const int cw4 = (w4 + ss_hor) >> ss_hor, ch4 = (h4 + ss_ver) >> ss_ver;
      const int has_chroma = f->cur.p.layout != DAV1D_PIXEL_LAYOUT_I400 &&
                             (bw4 > ss_hor || t->bx & 1) &&
                             (bh4 > ss_ver || t->by & 1);
      const TxfmInfo *const t_dim = &dav1d_txfm_dimensions[b->tx];
      const TxfmInfo *const uv_t_dim = &dav1d_txfm_dimensions[b->uvtx];
  
      // coefficient coding
      pixel *const edge = bitfn(t->scratch.edge) + 128;
      const int cbw4 = (bw4 + ss_hor) >> ss_hor, cbh4 = (bh4 + ss_ver) >> ss_ver;
  
      const int intra_edge_filter_flag = f->seq_hdr->intra_edge_filter << 10;
  
      for (int init_y = 0; init_y < h4; init_y += 16) {
          for (int init_x = 0; init_x < w4; init_x += 16) {
              if (b->pal_sz[0]) {
                  pixel *dst = ((pixel *) f->cur.data[0]) +
                               4 * (t->by * PXSTRIDE(f->cur.stride[0]) + t->bx);
                  const uint8_t *pal_idx;
                  if (f->frame_thread.pass) {
                      assert(ts->frame_thread.pal_idx);
                      pal_idx = ts->frame_thread.pal_idx;
                      ts->frame_thread.pal_idx += bw4 * bh4 * 16;
                  } else {
                      pal_idx = t->scratch.pal_idx;
                  }
                  const uint16_t *const pal = f->frame_thread.pass ?
                      f->frame_thread.pal[((t->by >> 1) + (t->bx & 1)) * (f->b4_stride >> 1) +
                                          ((t->bx >> 1) + (t->by & 1))][0] : t->scratch.pal[0];
                  f->dsp->ipred.pal_pred(dst, f->cur.stride[0], pal,
                                         pal_idx, bw4 * 4, bh4 * 4);
                  if (DEBUG_BLOCK_INFO && DEBUG_B_PIXELS)
                      hex_dump(dst, PXSTRIDE(f->cur.stride[0]),
                               bw4 * 4, bh4 * 4, "y-pal-pred");
              }
  
              const int intra_flags = (sm_flag(t->a, bx4) |
                                       sm_flag(&t->l, by4) |
                                       intra_edge_filter_flag);
              const int sb_has_tr = init_x + 16 < w4 ? 1 : init_y ? 0 :
                                intra_edge_flags & EDGE_I444_TOP_HAS_RIGHT;
              const int sb_has_bl = init_x ? 0 : init_y + 16 < h4 ? 1 :
                                intra_edge_flags & EDGE_I444_LEFT_HAS_BOTTOM;
              int y, x;
              const int sub_h4 = imin(h4, 16 + init_y);
              const int sub_w4 = imin(w4, init_x + 16);
              for (y = init_y, t->by += init_y; y < sub_h4;
                   y += t_dim->h, t->by += t_dim->h)
              {
                  pixel *dst = ((pixel *) f->cur.data[0]) +
                                 4 * (t->by * PXSTRIDE(f->cur.stride[0]) +
                                      t->bx + init_x);
                  for (x = init_x, t->bx += init_x; x < sub_w4;
                       x += t_dim->w, t->bx += t_dim->w)
                  {
                      if (b->pal_sz[0]) goto skip_y_pred;
  
                      int angle = b->y_angle;
                      const enum EdgeFlags edge_flags =
                          (((y > init_y || !sb_has_tr) && (x + t_dim->w >= sub_w4)) ?
                               0 : EDGE_I444_TOP_HAS_RIGHT) |
                          ((x > init_x || (!sb_has_bl && y + t_dim->h >= sub_h4)) ?
                               0 : EDGE_I444_LEFT_HAS_BOTTOM);
                      const pixel *top_sb_edge = NULL;
                      if (!(t->by & (f->sb_step - 1))) {
                          top_sb_edge = f->ipred_edge[0];
                          const int sby = t->by >> f->sb_shift;
                          top_sb_edge += f->sb128w * 128 * (sby - 1);
                      }
                      const enum IntraPredMode m =
                          bytefn(dav1d_prepare_intra_edges)(t->bx,
                                                            t->bx > ts->tiling.col_start,
                                                            t->by,
                                                            t->by > ts->tiling.row_start,
                                                            ts->tiling.col_end,
                                                            ts->tiling.row_end,
                                                            edge_flags, dst,
                                                            f->cur.stride[0], top_sb_edge,
                                                            b->y_mode, &angle,
                                                            t_dim->w, t_dim->h,
                                                            f->seq_hdr->intra_edge_filter,
                                                            edge HIGHBD_CALL_SUFFIX);
                      dsp->ipred.intra_pred[m](dst, f->cur.stride[0], edge,
                                               t_dim->w * 4, t_dim->h * 4,
                                               angle | intra_flags,
                                               4 * f->bw - 4 * t->bx,
                                               4 * f->bh - 4 * t->by
                                               HIGHBD_CALL_SUFFIX);
  
                      if (DEBUG_BLOCK_INFO && DEBUG_B_PIXELS) {
                          hex_dump(edge - t_dim->h * 4, t_dim->h * 4,
                                   t_dim->h * 4, 2, "l");
                          hex_dump(edge, 0, 1, 1, "tl");
                          hex_dump(edge + 1, t_dim->w * 4,
                                   t_dim->w * 4, 2, "t");
                          hex_dump(dst, f->cur.stride[0],
                                   t_dim->w * 4, t_dim->h * 4, "y-intra-pred");
                      }
  
                  skip_y_pred: {}
                      if (!b->skip) {
                          coef *cf;
                          int eob;
                          enum TxfmType txtp;
                          if (f->frame_thread.pass) {
                              cf = ts->frame_thread.cf;
                              ts->frame_thread.cf += imin(t_dim->w, 8) * imin(t_dim->h, 8) * 16;
                              const struct CodedBlockInfo *const cbi =
                                  &f->frame_thread.cbi[t->by * f->b4_stride + t->bx];
                              eob = cbi->eob[0];
                              txtp = cbi->txtp[0];
                          } else {
                              uint8_t cf_ctx;
                              cf = bitfn(t->cf);
                              eob = decode_coefs(t, &t->a->lcoef[bx4 + x],
                                                 &t->l.lcoef[by4 + y], b->tx, bs,
                                                 b, 1, 0, cf, &txtp, &cf_ctx);
                              if (DEBUG_BLOCK_INFO)
                                  printf("Post-y-cf-blk[tx=%d,txtp=%d,eob=%d]: r=%d\n",
                                         b->tx, txtp, eob, ts->msac.rng);
  #define set_ctx(type, dir, diridx, off, mul, rep_macro) \
                              rep_macro(type, t->dir lcoef, off, mul * cf_ctx)
  #define default_memset(dir, diridx, off, sz) \
                              memset(&t->dir lcoef[off], cf_ctx, sz)
                              case_set_upto16_with_default(imin(t_dim->h, f->bh - t->by), \
                                                           l., 1, by4 + y);
                              case_set_upto16_with_default(imin(t_dim->w, f->bw - t->bx), \
                                                           a->, 0, bx4 + x);
  #undef default_memset
  #undef set_ctx
                          }
                          if (eob >= 0) {
                              if (DEBUG_BLOCK_INFO && DEBUG_B_PIXELS)
                                  coef_dump(cf, imin(t_dim->h, 8) * 4,
                                            imin(t_dim->w, 8) * 4, 3, "dq");
                              dsp->itx.itxfm_add[b->tx]
                                                [txtp](dst,
                                                       f->cur.stride[0],
                                                       cf, eob HIGHBD_CALL_SUFFIX);
                              if (DEBUG_BLOCK_INFO && DEBUG_B_PIXELS)
                                  hex_dump(dst, f->cur.stride[0],
                                           t_dim->w * 4, t_dim->h * 4, "recon");
                          }
                      } else if (!f->frame_thread.pass) {
  #define set_ctx(type, dir, diridx, off, mul, rep_macro) \
                          rep_macro(type, t->dir lcoef, off, mul * 0x40)
                          case_set_upto16(t_dim->h, l., 1, by4 + y);
                          case_set_upto16(t_dim->w, a->, 0, bx4 + x);
  #undef set_ctx
                      }
                      dst += 4 * t_dim->w;
                  }
                  t->bx -= x;
              }
              t->by -= y;
  
              if (!has_chroma) continue;
  
              const ptrdiff_t stride = f->cur.stride[1];
  
              if (b->uv_mode == CFL_PRED) {
                  assert(!init_x && !init_y);
  
                  int16_t *const ac = t->scratch.ac;
                  pixel *y_src = ((pixel *) f->cur.data[0]) + 4 * (t->bx & ~ss_hor) +
                                   4 * (t->by & ~ss_ver) * PXSTRIDE(f->cur.stride[0]);
                  const ptrdiff_t uv_off = 4 * ((t->bx >> ss_hor) +
                                                (t->by >> ss_ver) * PXSTRIDE(stride));
                  pixel *const uv_dst[2] = { ((pixel *) f->cur.data[1]) + uv_off,
                                             ((pixel *) f->cur.data[2]) + uv_off };
  
                  const int furthest_r =
                      ((cw4 << ss_hor) + t_dim->w - 1) & ~(t_dim->w - 1);
                  const int furthest_b =
                      ((ch4 << ss_ver) + t_dim->h - 1) & ~(t_dim->h - 1);
                  dsp->ipred.cfl_ac[f->cur.p.layout - 1](ac, y_src, f->cur.stride[0],
                                                           cbw4 - (furthest_r >> ss_hor),
                                                           cbh4 - (furthest_b >> ss_ver),
                                                           cbw4 * 4, cbh4 * 4);
                  for (int pl = 0; pl < 2; pl++) {
                      if (!b->cfl_alpha[pl]) continue;
                      int angle = 0;
                      const pixel *top_sb_edge = NULL;
                      if (!((t->by & ~ss_ver) & (f->sb_step - 1))) {
                          top_sb_edge = f->ipred_edge[pl + 1];
                          const int sby = t->by >> f->sb_shift;
                          top_sb_edge += f->sb128w * 128 * (sby - 1);
                      }
                      const int xpos = t->bx >> ss_hor, ypos = t->by >> ss_ver;
                      const int xstart = ts->tiling.col_start >> ss_hor;
                      const int ystart = ts->tiling.row_start >> ss_ver;
                      const enum IntraPredMode m =
                          bytefn(dav1d_prepare_intra_edges)(xpos, xpos > xstart,
                                                            ypos, ypos > ystart,
                                                            ts->tiling.col_end >> ss_hor,
                                                            ts->tiling.row_end >> ss_ver,
                                                            0, uv_dst[pl], stride,
                                                            top_sb_edge, DC_PRED, &angle,
                                                            uv_t_dim->w, uv_t_dim->h, 0,
                                                            edge HIGHBD_CALL_SUFFIX);
                      dsp->ipred.cfl_pred[m](uv_dst[pl], stride, edge,
                                             uv_t_dim->w * 4,
                                             uv_t_dim->h * 4,
                                             ac, b->cfl_alpha[pl]
                                             HIGHBD_CALL_SUFFIX);
                  }
                  if (DEBUG_BLOCK_INFO && DEBUG_B_PIXELS) {
                      ac_dump(ac, 4*cbw4, 4*cbh4, "ac");
                      hex_dump(uv_dst[0], stride, cbw4 * 4, cbh4 * 4, "u-cfl-pred");
                      hex_dump(uv_dst[1], stride, cbw4 * 4, cbh4 * 4, "v-cfl-pred");
                  }
              } else if (b->pal_sz[1]) {
                  ptrdiff_t uv_dstoff = 4 * ((t->bx >> ss_hor) +
                                             (t->by >> ss_ver) * PXSTRIDE(f->cur.stride[1]));
                  const uint16_t (*pal)[8];
                  const uint8_t *pal_idx;
                  if (f->frame_thread.pass) {
                      assert(ts->frame_thread.pal_idx);
                      pal = f->frame_thread.pal[((t->by >> 1) + (t->bx & 1)) * (f->b4_stride >> 1) +
                                                ((t->bx >> 1) + (t->by & 1))];
                      pal_idx = ts->frame_thread.pal_idx;
                      ts->frame_thread.pal_idx += cbw4 * cbh4 * 16;
                  } else {
                      pal = t->scratch.pal;
                      pal_idx = &t->scratch.pal_idx[bw4 * bh4 * 16];
                  }
  
                  f->dsp->ipred.pal_pred(((pixel *) f->cur.data[1]) + uv_dstoff,
                                         f->cur.stride[1], pal[1],
                                         pal_idx, cbw4 * 4, cbh4 * 4);
                  f->dsp->ipred.pal_pred(((pixel *) f->cur.data[2]) + uv_dstoff,
                                         f->cur.stride[1], pal[2],
                                         pal_idx, cbw4 * 4, cbh4 * 4);
                  if (DEBUG_BLOCK_INFO && DEBUG_B_PIXELS) {
                      hex_dump(((pixel *) f->cur.data[1]) + uv_dstoff,
                               PXSTRIDE(f->cur.stride[1]),
                               cbw4 * 4, cbh4 * 4, "u-pal-pred");
                      hex_dump(((pixel *) f->cur.data[2]) + uv_dstoff,
                               PXSTRIDE(f->cur.stride[1]),
                               cbw4 * 4, cbh4 * 4, "v-pal-pred");
                  }
              }
  
              const int sm_uv_fl = sm_uv_flag(t->a, cbx4) |
                                   sm_uv_flag(&t->l, cby4);
              const int uv_sb_has_tr =
                  ((init_x + 16) >> ss_hor) < cw4 ? 1 : init_y ? 0 :
                  intra_edge_flags & (EDGE_I420_TOP_HAS_RIGHT >> (f->cur.p.layout - 1));
              const int uv_sb_has_bl =
                  init_x ? 0 : ((init_y + 16) >> ss_ver) < ch4 ? 1 :
                  intra_edge_flags & (EDGE_I420_LEFT_HAS_BOTTOM >> (f->cur.p.layout - 1));
              const int sub_ch4 = imin(ch4, (init_y + 16) >> ss_ver);
              const int sub_cw4 = imin(cw4, (init_x + 16) >> ss_hor);
              for (int pl = 0; pl < 2; pl++) {
                  for (y = init_y >> ss_ver, t->by += init_y; y < sub_ch4;
                       y += uv_t_dim->h, t->by += uv_t_dim->h << ss_ver)
                  {
                      pixel *dst = ((pixel *) f->cur.data[1 + pl]) +
                                     4 * ((t->by >> ss_ver) * PXSTRIDE(stride) +
                                          ((t->bx + init_x) >> ss_hor));
                      for (x = init_x >> ss_hor, t->bx += init_x; x < sub_cw4;
                           x += uv_t_dim->w, t->bx += uv_t_dim->w << ss_hor)
                      {
                          if ((b->uv_mode == CFL_PRED && b->cfl_alpha[pl]) ||
                              b->pal_sz[1])
                          {
                              goto skip_uv_pred;
                          }
  
                          int angle = b->uv_angle;
                          // this probably looks weird because we're using
                          // luma flags in a chroma loop, but that's because
                          // prepare_intra_edges() expects luma flags as input
                          const enum EdgeFlags edge_flags =
                              (((y > (init_y >> ss_ver) || !uv_sb_has_tr) &&
                                (x + uv_t_dim->w >= sub_cw4)) ?
                                   0 : EDGE_I444_TOP_HAS_RIGHT) |
                              ((x > (init_x >> ss_hor) ||
                                (!uv_sb_has_bl && y + uv_t_dim->h >= sub_ch4)) ?
                                   0 : EDGE_I444_LEFT_HAS_BOTTOM);
                          const pixel *top_sb_edge = NULL;
                          if (!((t->by & ~ss_ver) & (f->sb_step - 1))) {
                              top_sb_edge = f->ipred_edge[1 + pl];
                              const int sby = t->by >> f->sb_shift;
                              top_sb_edge += f->sb128w * 128 * (sby - 1);
                          }
                          const enum IntraPredMode uv_mode =
                               b->uv_mode == CFL_PRED ? DC_PRED : b->uv_mode;
                          const int xpos = t->bx >> ss_hor, ypos = t->by >> ss_ver;
                          const int xstart = ts->tiling.col_start >> ss_hor;
                          const int ystart = ts->tiling.row_start >> ss_ver;
                          const enum IntraPredMode m =
                              bytefn(dav1d_prepare_intra_edges)(xpos, xpos > xstart,
                                                                ypos, ypos > ystart,
                                                                ts->tiling.col_end >> ss_hor,
                                                                ts->tiling.row_end >> ss_ver,
                                                                edge_flags, dst, stride,
                                                                top_sb_edge, uv_mode,
                                                                &angle, uv_t_dim->w,
                                                                uv_t_dim->h,
                                                                f->seq_hdr->intra_edge_filter,
                                                                edge HIGHBD_CALL_SUFFIX);
                          angle |= intra_edge_filter_flag;
                          dsp->ipred.intra_pred[m](dst, stride, edge,
                                                   uv_t_dim->w * 4,
                                                   uv_t_dim->h * 4,
                                                   angle | sm_uv_fl,
                                                   (4 * f->bw + ss_hor -
                                                    4 * (t->bx & ~ss_hor)) >> ss_hor,
                                                   (4 * f->bh + ss_ver -
                                                    4 * (t->by & ~ss_ver)) >> ss_ver
                                                   HIGHBD_CALL_SUFFIX);
                          if (DEBUG_BLOCK_INFO && DEBUG_B_PIXELS) {
                              hex_dump(edge - uv_t_dim->h * 4, uv_t_dim->h * 4,
                                       uv_t_dim->h * 4, 2, "l");
                              hex_dump(edge, 0, 1, 1, "tl");
                              hex_dump(edge + 1, uv_t_dim->w * 4,
                                       uv_t_dim->w * 4, 2, "t");
                              hex_dump(dst, stride, uv_t_dim->w * 4,
                                       uv_t_dim->h * 4, pl ? "v-intra-pred" : "u-intra-pred");
                          }
  
                      skip_uv_pred: {}
                          if (!b->skip) {
                              enum TxfmType txtp;
                              int eob;
                              coef *cf;
                              if (f->frame_thread.pass) {
                                  cf = ts->frame_thread.cf;
                                  ts->frame_thread.cf += uv_t_dim->w * uv_t_dim->h * 16;
                                  const struct CodedBlockInfo *const cbi =
                                      &f->frame_thread.cbi[t->by * f->b4_stride + t->bx];
                                  eob = cbi->eob[pl + 1];
                                  txtp = cbi->txtp[pl + 1];
                              } else {
                                  uint8_t cf_ctx;
                                  cf = bitfn(t->cf);
                                  eob = decode_coefs(t, &t->a->ccoef[pl][cbx4 + x],
                                                     &t->l.ccoef[pl][cby4 + y],
                                                     b->uvtx, bs, b, 1, 1 + pl, cf,
                                                     &txtp, &cf_ctx);
                                  if (DEBUG_BLOCK_INFO)
                                      printf("Post-uv-cf-blk[pl=%d,tx=%d,"
                                             "txtp=%d,eob=%d]: r=%d [x=%d,cbx4=%d]\n",
                                             pl, b->uvtx, txtp, eob, ts->msac.rng, x, cbx4);
  #define set_ctx(type, dir, diridx, off, mul, rep_macro) \
                                  rep_macro(type, t->dir ccoef[pl], off, mul * cf_ctx)
  #define default_memset(dir, diridx, off, sz) \
                                  memset(&t->dir ccoef[pl][off], cf_ctx, sz)
                                  case_set_upto16_with_default( \
                                           imin(uv_t_dim->h, (f->bh - t->by + ss_ver) >> ss_ver),
                                           l., 1, cby4 + y);
                                  case_set_upto16_with_default( \
                                           imin(uv_t_dim->w, (f->bw - t->bx + ss_hor) >> ss_hor),
                                           a->, 0, cbx4 + x);
  #undef default_memset
  #undef set_ctx
                              }
                              if (eob >= 0) {
                                  if (DEBUG_BLOCK_INFO && DEBUG_B_PIXELS)
                                      coef_dump(cf, uv_t_dim->h * 4,
                                                uv_t_dim->w * 4, 3, "dq");
                                  dsp->itx.itxfm_add[b->uvtx]
                                                    [txtp](dst, stride,
                                                           cf, eob HIGHBD_CALL_SUFFIX);
                                  if (DEBUG_BLOCK_INFO && DEBUG_B_PIXELS)
                                      hex_dump(dst, stride, uv_t_dim->w * 4,
                                               uv_t_dim->h * 4, "recon");
                              }
                          } else if (!f->frame_thread.pass) {
  #define set_ctx(type, dir, diridx, off, mul, rep_macro) \
                              rep_macro(type, t->dir ccoef[pl], off, mul * 0x40)
                              case_set_upto16(uv_t_dim->h, l., 1, cby4 + y);
                              case_set_upto16(uv_t_dim->w, a->, 0, cbx4 + x);
  #undef set_ctx
                          }
                          dst += uv_t_dim->w * 4;
                      }
                      t->bx -= x << ss_hor;
                  }
                  t->by -= y << ss_ver;
              }
          }
      }
  }
  
  int bytefn(dav1d_recon_b_inter)(Dav1dTileContext *const t, const enum BlockSize bs,
                                   const Av1Block *const b)
  {
      Dav1dTileState *const ts = t->ts;
      const Dav1dFrameContext *const f = t->f;
      const Dav1dDSPContext *const dsp = f->dsp;
      const int bx4 = t->bx & 31, by4 = t->by & 31;
      const int ss_ver = f->cur.p.layout == DAV1D_PIXEL_LAYOUT_I420;
      const int ss_hor = f->cur.p.layout != DAV1D_PIXEL_LAYOUT_I444;
      const int cbx4 = bx4 >> ss_hor, cby4 = by4 >> ss_ver;
      const uint8_t *const b_dim = dav1d_block_dimensions[bs];
      const int bw4 = b_dim[0], bh4 = b_dim[1];
      const int w4 = imin(bw4, f->bw - t->bx), h4 = imin(bh4, f->bh - t->by);
      const int has_chroma = f->cur.p.layout != DAV1D_PIXEL_LAYOUT_I400 &&
                             (bw4 > ss_hor || t->bx & 1) &&
                             (bh4 > ss_ver || t->by & 1);
      const int chr_layout_idx = f->cur.p.layout == DAV1D_PIXEL_LAYOUT_I400 ? 0 :
                                 DAV1D_PIXEL_LAYOUT_I444 - f->cur.p.layout;
      int res;
  
      // prediction
      const int cbh4 = (bh4 + ss_ver) >> ss_ver, cbw4 = (bw4 + ss_hor) >> ss_hor;
      pixel *dst = ((pixel *) f->cur.data[0]) +
          4 * (t->by * PXSTRIDE(f->cur.stride[0]) + t->bx);
      const ptrdiff_t uvdstoff =
          4 * ((t->bx >> ss_hor) + (t->by >> ss_ver) * PXSTRIDE(f->cur.stride[1]));
      if (!(f->frame_hdr->frame_type & 1)) {
          // intrabc
          assert(!f->frame_hdr->super_res.enabled);
          res = mc(t, dst, NULL, f->cur.stride[0], bw4, bh4, t->bx, t->by, 0,
                   b->mv[0], &f->sr_cur, 0 /* unused */, FILTER_2D_BILINEAR);
          if (res) return res;
          if (has_chroma) for (int pl = 1; pl < 3; pl++) {
              res = mc(t, ((pixel *)f->cur.data[pl]) + uvdstoff, NULL, f->cur.stride[1],
                       bw4 << (bw4 == ss_hor), bh4 << (bh4 == ss_ver),
                       t->bx & ~ss_hor, t->by & ~ss_ver, pl, b->mv[0],
                       &f->sr_cur, 0 /* unused */, FILTER_2D_BILINEAR);
              if (res) return res;
          }
      } else if (b->comp_type == COMP_INTER_NONE) {
          const Dav1dThreadPicture *const refp = &f->refp[b->ref[0]];
          const enum Filter2d filter_2d = b->filter2d;
  
          if (imin(bw4, bh4) > 1 &&
              ((b->inter_mode == GLOBALMV && f->gmv_warp_allowed[b->ref[0]]) ||
               (b->motion_mode == MM_WARP && t->warpmv.type > DAV1D_WM_TYPE_TRANSLATION)))
          {
              res = warp_affine(t, dst, NULL, f->cur.stride[0], b_dim, 0, refp,
                                b->motion_mode == MM_WARP ? &t->warpmv :
                                    &f->frame_hdr->gmv[b->ref[0]]);
              if (res) return res;
          } else {
              res = mc(t, dst, NULL, f->cur.stride[0],
                       bw4, bh4, t->bx, t->by, 0, b->mv[0], refp, b->ref[0], filter_2d);
              if (res) return res;
              if (b->motion_mode == MM_OBMC) {
                  res = obmc(t, dst, f->cur.stride[0], b_dim, 0, bx4, by4, w4, h4);
                  if (res) return res;
              }
          }
          if (b->interintra_type) {
              pixel *const tl_edge = bitfn(t->scratch.edge) + 32;
              enum IntraPredMode m = b->interintra_mode == II_SMOOTH_PRED ?
                                     SMOOTH_PRED : b->interintra_mode;
              pixel *const tmp = bitfn(t->scratch.interintra);
              int angle = 0;
              const pixel *top_sb_edge = NULL;
              if (!(t->by & (f->sb_step - 1))) {
                  top_sb_edge = f->ipred_edge[0];
                  const int sby = t->by >> f->sb_shift;
                  top_sb_edge += f->sb128w * 128 * (sby - 1);
              }
              m = bytefn(dav1d_prepare_intra_edges)(t->bx, t->bx > ts->tiling.col_start,
                                                    t->by, t->by > ts->tiling.row_start,
                                                    ts->tiling.col_end, ts->tiling.row_end,
                                                    0, dst, f->cur.stride[0], top_sb_edge,
                                                    m, &angle, bw4, bh4, 0, tl_edge
                                                    HIGHBD_CALL_SUFFIX);
              dsp->ipred.intra_pred[m](tmp, 4 * bw4 * sizeof(pixel),
                                       tl_edge, bw4 * 4, bh4 * 4, 0, 0, 0
                                       HIGHBD_CALL_SUFFIX);
              const uint8_t *const ii_mask =
                  b->interintra_type == INTER_INTRA_BLEND ?
                       dav1d_ii_masks[bs][0][b->interintra_mode] :
                       dav1d_wedge_masks[bs][0][0][b->wedge_idx];
              dsp->mc.blend(dst, f->cur.stride[0], tmp,
                            bw4 * 4, bh4 * 4, ii_mask);
          }
  
          if (!has_chroma) goto skip_inter_chroma_pred;
  
          // sub8x8 derivation
          int is_sub8x8 = bw4 == ss_hor || bh4 == ss_ver;
          refmvs *r;
          if (is_sub8x8) {
              assert(ss_hor == 1);
              r = &f->mvs[t->by * f->b4_stride + t->bx];
              if (bw4 == 1) is_sub8x8 &= r[-1].ref[0] > 0;
              if (bh4 == ss_ver) is_sub8x8 &= r[-f->b4_stride].ref[0] > 0;
              if (bw4 == 1 && bh4 == ss_ver)
                  is_sub8x8 &= r[-(1 + f->b4_stride)].ref[0] > 0;
          }
  
          // chroma prediction
          if (is_sub8x8) {
              assert(ss_hor == 1);
              ptrdiff_t h_off = 0, v_off = 0;
              if (bw4 == 1 && bh4 == ss_ver) {
                  for (int pl = 0; pl < 2; pl++) {
                      res = mc(t, ((pixel *) f->cur.data[1 + pl]) + uvdstoff,
                               NULL, f->cur.stride[1],
                               bw4, bh4, t->bx - 1, t->by - 1, 1 + pl,
                               r[-(f->b4_stride + 1)].mv[0],
                               &f->refp[r[-(f->b4_stride + 1)].ref[0] - 1],
                               r[-(f->b4_stride + 1)].ref[0] - 1,
                               f->frame_thread.pass != 2 ? t->tl_4x4_filter :
                                   f->frame_thread.b[((t->by - 1) * f->b4_stride) + t->bx - 1].filter2d);
                      if (res) return res;
                  }
                  v_off = 2 * PXSTRIDE(f->cur.stride[1]);
                  h_off = 2;
              }
              if (bw4 == 1) {
                  const enum Filter2d left_filter_2d =
                      dav1d_filter_2d[t->l.filter[1][by4]][t->l.filter[0][by4]];
                  for (int pl = 0; pl < 2; pl++) {
                      res = mc(t, ((pixel *) f->cur.data[1 + pl]) + uvdstoff + v_off, NULL,
                               f->cur.stride[1], bw4, bh4, t->bx - 1,
                               t->by, 1 + pl, r[-1].mv[0], &f->refp[r[-1].ref[0] - 1],
                               r[-1].ref[0] - 1,
                               f->frame_thread.pass != 2 ? left_filter_2d :
                                   f->frame_thread.b[(t->by * f->b4_stride) + t->bx - 1].filter2d);
                      if (res) return res;
                  }
                  h_off = 2;
              }
              if (bh4 == ss_ver) {
                  const enum Filter2d top_filter_2d =
                      dav1d_filter_2d[t->a->filter[1][bx4]][t->a->filter[0][bx4]];
                  for (int pl = 0; pl < 2; pl++) {
                      res = mc(t, ((pixel *) f->cur.data[1 + pl]) + uvdstoff + h_off, NULL,
                               f->cur.stride[1], bw4, bh4, t->bx, t->by - 1,
                               1 + pl, r[-f->b4_stride].mv[0],
                               &f->refp[r[-f->b4_stride].ref[0] - 1],
                               r[-f->b4_stride].ref[0] - 1,
                               f->frame_thread.pass != 2 ? top_filter_2d :
                                   f->frame_thread.b[((t->by - 1) * f->b4_stride) + t->bx].filter2d);
                      if (res) return res;
                  }
                  v_off = 2 * PXSTRIDE(f->cur.stride[1]);
              }
              for (int pl = 0; pl < 2; pl++) {
                  res = mc(t, ((pixel *) f->cur.data[1 + pl]) + uvdstoff + h_off + v_off, NULL, f->cur.stride[1],
                           bw4, bh4, t->bx, t->by, 1 + pl, b->mv[0],
                           refp, b->ref[0], filter_2d);
                  if (res) return res;
              }
          } else {
              if (imin(cbw4, cbh4) > 1 &&
                  ((b->inter_mode == GLOBALMV && f->gmv_warp_allowed[b->ref[0]]) ||
                   (b->motion_mode == MM_WARP && t->warpmv.type > DAV1D_WM_TYPE_TRANSLATION)))
              {
                  for (int pl = 0; pl < 2; pl++) {
                      res = warp_affine(t, ((pixel *) f->cur.data[1 + pl]) + uvdstoff, NULL,
                                        f->cur.stride[1], b_dim, 1 + pl, refp,
                                        b->motion_mode == MM_WARP ? &t->warpmv :
                                            &f->frame_hdr->gmv[b->ref[0]]);
                      if (res) return res;
                  }
              } else {
                  for (int pl = 0; pl < 2; pl++) {
                      res = mc(t, ((pixel *) f->cur.data[1 + pl]) + uvdstoff,
                               NULL, f->cur.stride[1],
                               bw4 << (bw4 == ss_hor), bh4 << (bh4 == ss_ver),
                               t->bx & ~ss_hor, t->by & ~ss_ver,
                               1 + pl, b->mv[0], refp, b->ref[0], filter_2d);
                      if (res) return res;
                      if (b->motion_mode == MM_OBMC) {
                          res = obmc(t, ((pixel *) f->cur.data[1 + pl]) + uvdstoff,
                                     f->cur.stride[1], b_dim, 1 + pl, bx4, by4, w4, h4);
                          if (res) return res;
                      }
                  }
              }
              if (b->interintra_type) {
                  // FIXME for 8x32 with 4:2:2 subsampling, this probably does
                  // the wrong thing since it will select 4x16, not 4x32, as a
                  // transform size...
                  const uint8_t *const ii_mask =
                      b->interintra_type == INTER_INTRA_BLEND ?
                           dav1d_ii_masks[bs][chr_layout_idx][b->interintra_mode] :
                           dav1d_wedge_masks[bs][chr_layout_idx][0][b->wedge_idx];
  
                  for (int pl = 0; pl < 2; pl++) {
                      pixel *const tmp = bitfn(t->scratch.interintra);
                      pixel *const tl_edge = bitfn(t->scratch.edge) + 32;
                      enum IntraPredMode m =
                          b->interintra_mode == II_SMOOTH_PRED ?
                          SMOOTH_PRED : b->interintra_mode;
                      int angle = 0;
                      pixel *const uvdst = ((pixel *) f->cur.data[1 + pl]) + uvdstoff;
                      const pixel *top_sb_edge = NULL;
                      if (!(t->by & (f->sb_step - 1))) {
                          top_sb_edge = f->ipred_edge[pl + 1];
                          const int sby = t->by >> f->sb_shift;
                          top_sb_edge += f->sb128w * 128 * (sby - 1);
                      }
                      m = bytefn(dav1d_prepare_intra_edges)(t->bx >> ss_hor,
                                                            (t->bx >> ss_hor) >
                                                                (ts->tiling.col_start >> ss_hor),
                                                            t->by >> ss_ver,
                                                            (t->by >> ss_ver) >
                                                                (ts->tiling.row_start >> ss_ver),
                                                            ts->tiling.col_end >> ss_hor,
                                                            ts->tiling.row_end >> ss_ver,
                                                            0, uvdst, f->cur.stride[1],
                                                            top_sb_edge, m,
                                                            &angle, cbw4, cbh4, 0, tl_edge
                                                            HIGHBD_CALL_SUFFIX);
                      dsp->ipred.intra_pred[m](tmp, cbw4 * 4 * sizeof(pixel),
                                               tl_edge, cbw4 * 4, cbh4 * 4, 0, 0, 0
                                               HIGHBD_CALL_SUFFIX);
                      dsp->mc.blend(uvdst, f->cur.stride[1], tmp,
                                    cbw4 * 4, cbh4 * 4, ii_mask);
                  }
              }
          }
  
      skip_inter_chroma_pred: {}
          t->tl_4x4_filter = filter_2d;
      } else {
          const enum Filter2d filter_2d = b->filter2d;
          // Maximum super block size is 128x128
          int16_t (*tmp)[128 * 128] = t->scratch.compinter;
          int jnt_weight;
          uint8_t *const seg_mask = t->scratch.seg_mask;
          const uint8_t *mask;
  
          for (int i = 0; i < 2; i++) {
              const Dav1dThreadPicture *const refp = &f->refp[b->ref[i]];
  
              if (b->inter_mode == GLOBALMV_GLOBALMV && f->gmv_warp_allowed[b->ref[i]]) {
                  res = warp_affine(t, NULL, tmp[i], bw4 * 4, b_dim, 0, refp,
                                    &f->frame_hdr->gmv[b->ref[i]]);
                  if (res) return res;
              } else {
                  res = mc(t, NULL, tmp[i], 0, bw4, bh4, t->bx, t->by, 0,
                           b->mv[i], refp, b->ref[i], filter_2d);
                  if (res) return res;
              }
          }
          switch (b->comp_type) {
          case COMP_INTER_AVG:
              dsp->mc.avg(dst, f->cur.stride[0], tmp[0], tmp[1],
                          bw4 * 4, bh4 * 4 HIGHBD_CALL_SUFFIX);
              break;
          case COMP_INTER_WEIGHTED_AVG:
              jnt_weight = f->jnt_weights[b->ref[0]][b->ref[1]];
              dsp->mc.w_avg(dst, f->cur.stride[0], tmp[0], tmp[1],
                            bw4 * 4, bh4 * 4, jnt_weight HIGHBD_CALL_SUFFIX);
              break;
          case COMP_INTER_SEG:
              dsp->mc.w_mask[chr_layout_idx](dst, f->cur.stride[0],
                                             tmp[b->mask_sign], tmp[!b->mask_sign],
                                             bw4 * 4, bh4 * 4, seg_mask,
                                             b->mask_sign HIGHBD_CALL_SUFFIX);
              mask = seg_mask;
              break;
          case COMP_INTER_WEDGE:
              mask = dav1d_wedge_masks[bs][0][0][b->wedge_idx];
              dsp->mc.mask(dst, f->cur.stride[0],
                           tmp[b->mask_sign], tmp[!b->mask_sign],
                           bw4 * 4, bh4 * 4, mask HIGHBD_CALL_SUFFIX);
              if (has_chroma)
                  mask = dav1d_wedge_masks[bs][chr_layout_idx][b->mask_sign][b->wedge_idx];
              break;
          }
  
          // chroma
          if (has_chroma) for (int pl = 0; pl < 2; pl++) {
              for (int i = 0; i < 2; i++) {
                  const Dav1dThreadPicture *const refp = &f->refp[b->ref[i]];
                  if (b->inter_mode == GLOBALMV_GLOBALMV &&
                      imin(cbw4, cbh4) > 1 && f->gmv_warp_allowed[b->ref[i]])
                  {
                      res = warp_affine(t, NULL, tmp[i], bw4 * 4 >> ss_hor,
                                        b_dim, 1 + pl,
                                        refp, &f->frame_hdr->gmv[b->ref[i]]);
                      if (res) return res;
                  } else {
                      res = mc(t, NULL, tmp[i], 0, bw4, bh4, t->bx, t->by,
                               1 + pl, b->mv[i], refp, b->ref[i], filter_2d);
                      if (res) return res;
                  }
              }
              pixel *const uvdst = ((pixel *) f->cur.data[1 + pl]) + uvdstoff;
              switch (b->comp_type) {
              case COMP_INTER_AVG:
                  dsp->mc.avg(uvdst, f->cur.stride[1], tmp[0], tmp[1],
                              bw4 * 4 >> ss_hor, bh4 * 4 >> ss_ver
                              HIGHBD_CALL_SUFFIX);
                  break;
              case COMP_INTER_WEIGHTED_AVG:
                  dsp->mc.w_avg(uvdst, f->cur.stride[1], tmp[0], tmp[1],
                                bw4 * 4 >> ss_hor, bh4 * 4 >> ss_ver, jnt_weight
                                HIGHBD_CALL_SUFFIX);
                  break;
              case COMP_INTER_WEDGE:
              case COMP_INTER_SEG:
                  dsp->mc.mask(uvdst, f->cur.stride[1],
                               tmp[b->mask_sign], tmp[!b->mask_sign],
                               bw4 * 4 >> ss_hor, bh4 * 4 >> ss_ver, mask
                               HIGHBD_CALL_SUFFIX);
                  break;
              }
          }
      }
  
      if (DEBUG_BLOCK_INFO && DEBUG_B_PIXELS) {
          hex_dump(dst, f->cur.stride[0], b_dim[0] * 4, b_dim[1] * 4, "y-pred");
          if (has_chroma) {
              hex_dump(&((pixel *) f->cur.data[1])[uvdstoff], f->cur.stride[1],
                       cbw4 * 4, cbh4 * 4, "u-pred");
              hex_dump(&((pixel *) f->cur.data[2])[uvdstoff], f->cur.stride[1],
                       cbw4 * 4, cbh4 * 4, "v-pred");
          }
      }
  
      const int cw4 = (w4 + ss_hor) >> ss_hor, ch4 = (h4 + ss_ver) >> ss_ver;
  
      if (b->skip) {
          // reset coef contexts
  #define set_ctx(type, dir, diridx, off, mul, rep_macro) \
          rep_macro(type, t->dir lcoef, off, mul * 0x40)
          case_set(bh4, l., 1, by4);
          case_set(bw4, a->, 0, bx4);
  #undef set_ctx
          if (has_chroma) {
  #define set_ctx(type, dir, diridx, off, mul, rep_macro) \
              rep_macro(type, t->dir ccoef[0], off, mul * 0x40); \
              rep_macro(type, t->dir ccoef[1], off, mul * 0x40)
              case_set(cbh4, l., 1, cby4);
              case_set(cbw4, a->, 0, cbx4);
  #undef set_ctx
          }
          return 0;
      }
  
      const TxfmInfo *const uvtx = &dav1d_txfm_dimensions[b->uvtx];
      const TxfmInfo *const ytx = &dav1d_txfm_dimensions[b->max_ytx];
  
      for (int init_y = 0; init_y < bh4; init_y += 16) {
          for (int init_x = 0; init_x < bw4; init_x += 16) {
              // coefficient coding & inverse transforms
              int y_off = !!init_y, y;
              dst += PXSTRIDE(f->cur.stride[0]) * 4 * init_y;
              for (y = init_y, t->by += init_y; y < imin(h4, init_y + 16);
                   y += ytx->h, y_off++)
              {
                  int x, x_off = !!init_x;
                  for (x = init_x, t->bx += init_x; x < imin(w4, init_x + 16);
                       x += ytx->w, x_off++)
                  {
                      read_coef_tree(t, bs, b, b->max_ytx, 0, b->tx_split,
                                     x_off, y_off, &dst[x * 4]);
                      t->bx += ytx->w;
                  }
                  dst += PXSTRIDE(f->cur.stride[0]) * 4 * ytx->h;
                  t->bx -= x;
                  t->by += ytx->h;
              }
              dst -= PXSTRIDE(f->cur.stride[0]) * 4 * y;
              t->by -= y;
  
              // chroma coefs and inverse transform
              if (has_chroma) for (int pl = 0; pl < 2; pl++) {
                  pixel *uvdst = ((pixel *) f->cur.data[1 + pl]) + uvdstoff +
                      (PXSTRIDE(f->cur.stride[1]) * init_y * 4 >> ss_ver);
                  for (y = init_y >> ss_ver, t->by += init_y;
                       y < imin(ch4, (init_y + 16) >> ss_ver); y += uvtx->h)
                  {
                      int x;
                      for (x = init_x >> ss_hor, t->bx += init_x;
                           x < imin(cw4, (init_x + 16) >> ss_hor); x += uvtx->w)
                      {
                          coef *cf;
                          int eob;
                          enum TxfmType txtp;
                          if (f->frame_thread.pass) {
                              cf = ts->frame_thread.cf;
                              ts->frame_thread.cf += uvtx->w * uvtx->h * 16;
                              const struct CodedBlockInfo *const cbi =
                                  &f->frame_thread.cbi[t->by * f->b4_stride + t->bx];
                              eob = cbi->eob[1 + pl];
                              txtp = cbi->txtp[1 + pl];
                          } else {
                              uint8_t cf_ctx;
                              cf = bitfn(t->cf);
                              txtp = t->txtp_map[(by4 + (y << ss_ver)) * 32 +
                                                  bx4 + (x << ss_hor)];
                              eob = decode_coefs(t, &t->a->ccoef[pl][cbx4 + x],
                                                 &t->l.ccoef[pl][cby4 + y],
                                                 b->uvtx, bs, b, 0, 1 + pl,
                                                 cf, &txtp, &cf_ctx);
                              if (DEBUG_BLOCK_INFO)
                                  printf("Post-uv-cf-blk[pl=%d,tx=%d,"
                                         "txtp=%d,eob=%d]: r=%d\n",
                                         pl, b->uvtx, txtp, eob, ts->msac.rng);
  #define set_ctx(type, dir, diridx, off, mul, rep_macro) \
                              rep_macro(type, t->dir ccoef[pl], off, mul * cf_ctx)
  #define default_memset(dir, diridx, off, sz) \
                              memset(&t->dir ccoef[pl][off], cf_ctx, sz)
                              case_set_upto16_with_default( \
                                       imin(uvtx->h, (f->bh - t->by + ss_ver) >> ss_ver),
                                       l., 1, cby4 + y);
                              case_set_upto16_with_default( \
                                       imin(uvtx->w, (f->bw - t->bx + ss_hor) >> ss_hor),
                                       a->, 0, cbx4 + x);
  #undef default_memset
  #undef set_ctx
                          }
                          if (eob >= 0) {
                              if (DEBUG_BLOCK_INFO && DEBUG_B_PIXELS)
                                  coef_dump(cf, uvtx->h * 4, uvtx->w * 4, 3, "dq");
                              dsp->itx.itxfm_add[b->uvtx]
                                                [txtp](&uvdst[4 * x],
                                                       f->cur.stride[1],
                                                       cf, eob HIGHBD_CALL_SUFFIX);
                              if (DEBUG_BLOCK_INFO && DEBUG_B_PIXELS)
                                  hex_dump(&uvdst[4 * x], f->cur.stride[1],
                                           uvtx->w * 4, uvtx->h * 4, "recon");
                          }
                          t->bx += uvtx->w << ss_hor;
                      }
                      uvdst += PXSTRIDE(f->cur.stride[1]) * 4 * uvtx->h;
                      t->bx -= x << ss_hor;
                      t->by += uvtx->h << ss_ver;
                  }
                  t->by -= y << ss_ver;
              }
          }
      }
      return 0;
  }
  
  void bytefn(dav1d_filter_sbrow)(Dav1dFrameContext *const f, const int sby) {
      const int sbsz = f->sb_step, sbh = f->sbh;
  
      if (f->frame_hdr->loopfilter.level_y[0] ||
          f->frame_hdr->loopfilter.level_y[1])
      {
          int start_of_tile_row = 0;
          if (f->frame_hdr->tiling.row_start_sb[f->lf.tile_row] == sby)
              start_of_tile_row = f->lf.tile_row++;
          bytefn(dav1d_loopfilter_sbrow)(f, f->lf.p, f->lf.mask_ptr, sby,
                                         start_of_tile_row);
      }
  
      if (f->lf.restore_planes) {
          // Store loop filtered pixels required by loop restoration
          bytefn(dav1d_lr_copy_lpf)(f, f->lf.p, sby);
      }
      if (f->seq_hdr->cdef) {
          if (sby) {
              const int ss_ver = f->cur.p.layout == DAV1D_PIXEL_LAYOUT_I420;
              pixel *p_up[3] = {
                  f->lf.p[0] - 8 * PXSTRIDE(f->cur.stride[0]),
                  f->lf.p[1] - (8 * PXSTRIDE(f->cur.stride[1]) >> ss_ver),
                  f->lf.p[2] - (8 * PXSTRIDE(f->cur.stride[1]) >> ss_ver),
              };
              bytefn(dav1d_cdef_brow)(f, p_up, f->lf.prev_mask_ptr,
                                      sby * sbsz - 2, sby * sbsz);
          }
          const int n_blks = sbsz - 2 * (sby + 1 < sbh);
          bytefn(dav1d_cdef_brow)(f, f->lf.p, f->lf.mask_ptr, sby * sbsz,
                                  imin(sby * sbsz + n_blks, f->bh));
      }
      if (f->frame_hdr->width[0] != f->frame_hdr->width[1]) {
          const int has_chroma = f->cur.p.layout != DAV1D_PIXEL_LAYOUT_I400;
          for (int pl = 0; pl < 1 + 2 * has_chroma; pl++) {
              const int ss_ver = pl && f->cur.p.layout == DAV1D_PIXEL_LAYOUT_I420;
              const int h_start = 8 * !!sby >> ss_ver;
              const ptrdiff_t dst_stride = f->sr_cur.p.stride[!!pl];
              pixel *dst = f->lf.sr_p[pl] - h_start * PXSTRIDE(dst_stride);
              const ptrdiff_t src_stride = f->cur.stride[!!pl];
              const pixel *src = f->lf.p[pl] - h_start * PXSTRIDE(src_stride);
              const int h_end = 4 * (sbsz - 2 * (sby + 1 < sbh)) >> ss_ver;
              const int ss_hor = pl && f->cur.p.layout != DAV1D_PIXEL_LAYOUT_I444;
              const int dst_w = (f->sr_cur.p.p.w + ss_hor) >> ss_hor;
              const int src_w = (4 * f->bw + ss_hor) >> ss_hor;
              const int img_h = (f->cur.p.h - sbsz * 4 * sby + ss_ver) >> ss_ver;
  
              f->dsp->mc.resize(dst, dst_stride, src, src_stride, dst_w, src_w,
                                imin(img_h, h_end) + h_start, f->resize_step[!!pl],
                                f->resize_start[!!pl] HIGHBD_CALL_SUFFIX);
          }
      }
      if (f->lf.restore_planes) {
          bytefn(dav1d_lr_sbrow)(f, f->lf.sr_p, sby);
      }
  
      const int ss_ver = f->cur.p.layout == DAV1D_PIXEL_LAYOUT_I420;
      f->lf.p[0] += sbsz * 4 * PXSTRIDE(f->cur.stride[0]);
      f->lf.p[1] += sbsz * 4 * PXSTRIDE(f->cur.stride[1]) >> ss_ver;
      f->lf.p[2] += sbsz * 4 * PXSTRIDE(f->cur.stride[1]) >> ss_ver;
      f->lf.sr_p[0] += sbsz * 4 * PXSTRIDE(f->sr_cur.p.stride[0]);
      f->lf.sr_p[1] += sbsz * 4 * PXSTRIDE(f->sr_cur.p.stride[1]) >> ss_ver;
      f->lf.sr_p[2] += sbsz * 4 * PXSTRIDE(f->sr_cur.p.stride[1]) >> ss_ver;
      f->lf.prev_mask_ptr = f->lf.mask_ptr;
      if ((sby & 1) || f->seq_hdr->sb128) {
          f->lf.mask_ptr += f->sb128w;
      }
  }
  
  void bytefn(dav1d_backup_ipred_edge)(Dav1dTileContext *const t) {
      const Dav1dFrameContext *const f = t->f;
      Dav1dTileState *const ts = t->ts;
      const int sby = t->by >> f->sb_shift;
      const int sby_off = f->sb128w * 128 * sby;
      const int x_off = ts->tiling.col_start;
  
      const pixel *const y =
          ((const pixel *) f->cur.data[0]) + x_off * 4 +
                      ((t->by + f->sb_step) * 4 - 1) * PXSTRIDE(f->cur.stride[0]);
      pixel_copy(&f->ipred_edge[0][sby_off + x_off * 4], y,
                 4 * (ts->tiling.col_end - x_off));
  
      if (f->cur.p.layout != DAV1D_PIXEL_LAYOUT_I400) {
          const int ss_ver = f->cur.p.layout == DAV1D_PIXEL_LAYOUT_I420;
          const int ss_hor = f->cur.p.layout != DAV1D_PIXEL_LAYOUT_I444;
  
          const ptrdiff_t uv_off = (x_off * 4 >> ss_hor) +
              (((t->by + f->sb_step) * 4 >> ss_ver) - 1) * PXSTRIDE(f->cur.stride[1]);
          for (int pl = 1; pl <= 2; pl++)
              pixel_copy(&f->ipred_edge[pl][sby_off + (x_off * 4 >> ss_hor)],
                         &((const pixel *) f->cur.data[pl])[uv_off],
                         4 * (ts->tiling.col_end - x_off) >> ss_hor);
      }
  }
  