Merge "Add AVX vectorized vp9_diamond_search_sad"

vp9/common/vp9_rtcd_defs.pl

@@ -312,7 +312,7 @@ $vp9_full_search_sad_sse3=vp9_full_search_sadx3;
 $vp9_full_search_sad_sse4_1=vp9_full_search_sadx8;
 
 add_proto qw/int vp9_diamond_search_sad/, "const struct macroblock *x, const struct search_site_config *cfg,  struct mv *ref_mv, struct mv *best_mv, int search_param, int sad_per_bit, int *num00, const struct vp9_variance_vtable *fn_ptr, const struct mv *center_mv";
-specialize qw/vp9_diamond_search_sad/;
+specialize qw/vp9_diamond_search_sad avx/;
 
 add_proto qw/int vp9_full_range_search/, "const struct macroblock *x, const struct search_site_config *cfg, struct mv *ref_mv, struct mv *best_mv, int search_param, int sad_per_bit, int *num00, const struct vp9_variance_vtable *fn_ptr, const struct mv *center_mv";
 specialize qw/vp9_full_range_search/;

vp9/encoder/vp9_encoder.c

@@ -1570,7 +1570,30 @@ void vp9_change_config(struct VP9_COMP *cpi, const VP9EncoderConfig *oxcf) {
 #endif
 #define log2f(x) (log (x) / (float) M_LOG2_E)
 
+/***********************************************************************
+ * Read before modifying 'cal_nmvjointsadcost' or 'cal_nmvsadcosts'    *
+ ***********************************************************************
+ * The following 2 functions ('cal_nmvjointsadcost' and                *
+ * 'cal_nmvsadcosts') are used to calculate cost lookup tables         *
+ * used by 'vp9_diamond_search_sad'. The C implementation of the       *
+ * function is generic, but the AVX intrinsics optimised version       *
+ * relies on the following properties of the computed tables:          *
+ * For cal_nmvjointsadcost:                                            *
+ *   - mvjointsadcost[1] == mvjointsadcost[2] == mvjointsadcost[3]     *
+ * For cal_nmvsadcosts:                                                *
+ *   - For all i: mvsadcost[0][i] == mvsadcost[1][i]                   *
+ *         (Equal costs for both components)                           *
+ *   - For all i: mvsadcost[0][i] == mvsadcost[0][-i]                  *
+ *         (Cost function is even)                                     *
+ * If these do not hold, then the AVX optimised version of the         *
+ * 'vp9_diamond_search_sad' function cannot be used as it is, in which *
+ * case you can revert to using the C function instead.                *
+ ***********************************************************************/
+
 static void cal_nmvjointsadcost(int *mvjointsadcost) {
+  /*********************************************************************
+   * Warning: Read the comments above before modifying this function   *
+   *********************************************************************/
   mvjointsadcost[0] = 600;
   mvjointsadcost[1] = 300;
   mvjointsadcost[2] = 300;
@@ -1578,6 +1601,9 @@ static void cal_nmvjointsadcost(int *mvjointsadcost) {
 }
 
 static void cal_nmvsadcosts(int *mvsadcost[2]) {
+  /*********************************************************************
+   * Warning: Read the comments above before modifying this function   *
+   *********************************************************************/
   int i = 1;
 
   mvsadcost[0][0] = 0;
@@ -1739,6 +1765,10 @@ VP9_COMP *vp9_create_compressor(VP9EncoderConfig *oxcf,
 
   cpi->first_time_stamp_ever = INT64_MAX;
 
+  /*********************************************************************
+   * Warning: Read the comments around 'cal_nmvjointsadcost' and       *
+   * 'cal_nmvsadcosts' before modifying how these tables are computed. *
+   *********************************************************************/
   cal_nmvjointsadcost(cpi->td.mb.nmvjointsadcost);
   cpi->td.mb.nmvcost[0] = &cpi->nmvcosts[0][MV_MAX];
   cpi->td.mb.nmvcost[1] = &cpi->nmvcosts[1][MV_MAX];

vp9/encoder/vp9_mcomp.c

@@ -101,11 +101,8 @@ static int mvsad_err_cost(const MACROBLOCK *x, const MV *mv, const MV *ref,
 }
 
 void vp9_init_dsmotion_compensation(search_site_config *cfg, int stride) {
-  int len, ss_count = 1;
-
-  cfg->ss_mv[0].col = 0;
-  cfg->ss_mv[0].row = 0;
-  cfg->ss_os[0] = 0;
+  int len;
+  int ss_count = 0;
 
   for (len = MAX_FIRST_STEP; len > 0; len /= 2) {
     // Generate offsets for 4 search sites per step.
@@ -117,16 +114,13 @@ void vp9_init_dsmotion_compensation(search_site_config *cfg, int stride) {
     }
   }
 
-  cfg->ss_count = ss_count;
   cfg->searches_per_step = 4;
+  cfg->total_steps = ss_count / cfg->searches_per_step;
 }
 
 void vp9_init3smotion_compensation(search_site_config *cfg, int stride) {
-  int len, ss_count = 1;
-
-  cfg->ss_mv[0].col = 0;
-  cfg->ss_mv[0].row = 0;
-  cfg->ss_os[0] = 0;
+  int len;
+  int ss_count = 0;
 
   for (len = MAX_FIRST_STEP; len > 0; len /= 2) {
     // Generate offsets for 8 search sites per step.
@@ -141,8 +135,8 @@ void vp9_init3smotion_compensation(search_site_config *cfg, int stride) {
     }
   }
 
-  cfg->ss_count = ss_count;
   cfg->searches_per_step = 8;
+  cfg->total_steps = ss_count / cfg->searches_per_step;
 }
 
 /*
@@ -1612,8 +1606,8 @@ int vp9_diamond_search_sad_c(const MACROBLOCK *x,
   const uint8_t *best_address;
 
   unsigned int bestsad = INT_MAX;
-  int best_site = 0;
-  int last_site = 0;
+  int best_site = -1;
+  int last_site = -1;
 
   int ref_row;
   int ref_col;
@@ -1626,7 +1620,7 @@ int vp9_diamond_search_sad_c(const MACROBLOCK *x,
 //  const search_site *ss = &cfg->ss[search_param * cfg->searches_per_step];
   const MV *ss_mv = &cfg->ss_mv[search_param * cfg->searches_per_step];
   const intptr_t *ss_os = &cfg->ss_os[search_param * cfg->searches_per_step];
-  const int tot_steps = (cfg->ss_count / cfg->searches_per_step) - search_param;
+  const int tot_steps = (cfg->total_steps) - search_param;
 
   const MV fcenter_mv = {center_mv->row >> 3, center_mv->col >> 3};
   clamp_mv(ref_mv, x->mv_col_min, x->mv_col_max, x->mv_row_min, x->mv_row_max);
@@ -1644,7 +1638,7 @@ int vp9_diamond_search_sad_c(const MACROBLOCK *x,
   bestsad = fn_ptr->sdf(what, what_stride, in_what, in_what_stride)
                 + mvsad_err_cost(x, best_mv, &fcenter_mv, sad_per_bit);
 
-  i = 1;
+  i = 0;
 
   for (step = 0; step < tot_steps; step++) {
     int all_in = 1, t;

vp9/encoder/vp9_mcomp.h

@@ -33,10 +33,10 @@ extern "C" {
 
 typedef struct search_site_config {
   // motion search sites
-  MV  ss_mv[8 * MAX_MVSEARCH_STEPS + 1];        // Motion vector
-  intptr_t ss_os[8 * MAX_MVSEARCH_STEPS + 1];   // Offset
-  int ss_count;
+  MV  ss_mv[8 * MAX_MVSEARCH_STEPS];        // Motion vector
+  intptr_t ss_os[8 * MAX_MVSEARCH_STEPS];   // Offset
   int searches_per_step;
+  int total_steps;
 } search_site_config;
 
 void vp9_init_dsmotion_compensation(search_site_config *cfg, int stride);

vp9/encoder/x86/vp9_diamond_search_sad_avx.c

+/*
+ *  Copyright (c) 2015 The WebM project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include <emmintrin.h>
+#include <smmintrin.h>
+
+#include "vpx_dsp/vpx_dsp_common.h"
+#include "vp9/encoder/vp9_encoder.h"
+#include "vpx_ports/mem.h"
+
+#ifdef __GNUC__
+# define __likely__(v)    __builtin_expect(v, 1)
+# define __unlikely__(v)  __builtin_expect(v, 0)
+#else
+# define __likely__(v)    (v)
+# define __unlikely__(v)  (v)
+#endif
+
+static INLINE MV_JOINT_TYPE get_mv_joint(const int_mv mv) {
+  // This is simplified from the C implementation to utilise that
+  //  x->nmvjointsadcost[1] == x->nmvjointsadcost[2]  and
+  //  x->nmvjointsadcost[1] == x->nmvjointsadcost[3]
+  return mv.as_int == 0 ? 0 : 1;
+}
+
+static INLINE int mv_cost(const int_mv mv,
+                          const int *joint_cost, int *const comp_cost[2]) {
+  return joint_cost[get_mv_joint(mv)] +
+             comp_cost[0][mv.as_mv.row] + comp_cost[1][mv.as_mv.col];
+}
+
+static int mvsad_err_cost(const MACROBLOCK *x, const int_mv mv, const MV *ref,
+                          int error_per_bit) {
+  const int_mv diff = { .as_mv={  mv.as_mv.row - ref->row,
+                                  mv.as_mv.col - ref->col } };
+  return ROUND_POWER_OF_TWO(mv_cost(diff, x->nmvjointsadcost,
+                                    x->nmvsadcost) * error_per_bit, 8);
+}
+
+/*****************************************************************************
+ * This function utilises 3 properties of the cost function lookup tables,   *
+ * constructed in using 'cal_nmvjointsadcost' and 'cal_nmvsadcosts' in       *
+ * vp9_encoder.c.                                                            *
+ * For the joint cost:                                                       *
+ *   - mvjointsadcost[1] == mvjointsadcost[2] == mvjointsadcost[3]           *
+ * For the component costs:                                                  *
+ *   - For all i: mvsadcost[0][i] == mvsadcost[1][i]                         *
+ *         (Equal costs for both components)                                 *
+ *   - For all i: mvsadcost[0][i] == mvsadcost[0][-i]                        *
+ *         (Cost function is even)                                           *
+ * If these do not hold, then this function cannot be used without           *
+ * modification, in which case you can revert to using the C implementation, *
+ * which does not rely on these properties.                                  *
+ *****************************************************************************/
+int vp9_diamond_search_sad_avx(const MACROBLOCK *x,
+                             const search_site_config *cfg,
+                             MV *ref_mv, MV *best_mv, int search_param,
+                             int sad_per_bit, int *num00,
+                             const vp9_variance_fn_ptr_t *fn_ptr,
+                             const MV *center_mv) {
+  const int_mv maxmv = { .as_mv={x->mv_row_max, x->mv_col_max} };
+  const __m128i v_max_mv_w = _mm_set1_epi32(maxmv.as_int);
+  const int_mv minmv = { .as_mv={x->mv_row_min, x->mv_col_min} };
+  const __m128i v_min_mv_w = _mm_set1_epi32(minmv.as_int);
+
+  const __m128i v_spb_d = _mm_set1_epi32(sad_per_bit);
+
+  const __m128i v_joint_cost_0_d = _mm_set1_epi32(x->nmvjointsadcost[0]);
+  const __m128i v_joint_cost_1_d = _mm_set1_epi32(x->nmvjointsadcost[1]);
+
+  // search_param determines the length of the initial step and hence the number
+  // of iterations.
+  // 0 = initial step (MAX_FIRST_STEP) pel
+  // 1 = (MAX_FIRST_STEP/2) pel,
+  // 2 = (MAX_FIRST_STEP/4) pel...
+  const       MV *ss_mv = &cfg->ss_mv[cfg->searches_per_step * search_param];
+  const intptr_t *ss_os = &cfg->ss_os[cfg->searches_per_step * search_param];
+  const int tot_steps = cfg->total_steps - search_param;
+
+  const int_mv fcenter_mv = { .as_mv={center_mv->row >> 3,
+                                      center_mv->col >> 3} };
+  const __m128i vfcmv = _mm_set1_epi32(fcenter_mv.as_int);
+
+  const int ref_row = clamp(ref_mv->row, minmv.as_mv.row, maxmv.as_mv.row);
+  const int ref_col = clamp(ref_mv->col, minmv.as_mv.col, maxmv.as_mv.col);
+
+  int_mv bmv = { .as_mv={ ref_row, ref_col} };
+  int_mv new_bmv = bmv;
+  __m128i v_bmv_w = _mm_set1_epi32(bmv.as_int);
+
+  const     int         what_stride = x->plane[0].src.stride;
+  const uint8_t * const what = x->plane[0].src.buf;
+  const     int         in_what_stride = x->e_mbd.plane[0].pre[0].stride;
+  const uint8_t * const in_what = x->e_mbd.plane[0].pre[0].buf +
+                                  ref_row * in_what_stride + ref_col;
+
+  // Work out the start point for the search
+  const uint8_t *best_address = in_what;
+  const uint8_t *new_best_address = best_address;
+#if ARCH_X86_64
+  __m128i v_ba_q = _mm_set1_epi64x((intptr_t)best_address);
+#else
+  __m128i v_ba_d = _mm_set1_epi32((intptr_t)best_address);
+#endif
+
+  unsigned int best_sad;
+
+  int i;
+  int j;
+  int step;
+
+  // Check the starting position
+  best_sad = fn_ptr->sdf(what, what_stride, in_what, in_what_stride);
+  best_sad += mvsad_err_cost(x, bmv, &fcenter_mv.as_mv, sad_per_bit);
+
+  *num00 = 0;
+
+  for (i = 0, step = 0; step < tot_steps; step++) {
+    for (j = 0; j < cfg->searches_per_step; j += 4, i += 4) {
+      __m128i v_sad_d;
+      __m128i v_cost_d;
+      __m128i v_outside_d;
+      __m128i v_inside_d;
+      __m128i v_diff_mv_w;
+#if ARCH_X86_64
+      __m128i v_blocka[2];
+#else
+      __m128i v_blocka[1];
+#endif
+
+      // Compute the candidate motion vectors
+      const __m128i v_ss_mv_w = _mm_load_si128((const __m128i*)&ss_mv[i]);
+      const __m128i v_these_mv_w = _mm_add_epi16(v_bmv_w, v_ss_mv_w);
+      // Clamp them to the search bounds
+      __m128i v_these_mv_clamp_w = v_these_mv_w;
+      v_these_mv_clamp_w = _mm_min_epi16(v_these_mv_clamp_w, v_max_mv_w);
+      v_these_mv_clamp_w = _mm_max_epi16(v_these_mv_clamp_w, v_min_mv_w);
+      // The ones that did not change are inside the search area
+      v_inside_d = _mm_cmpeq_epi32(v_these_mv_clamp_w, v_these_mv_w);
+
+      // If none of them are inside, then move on
+      if (__likely__(_mm_test_all_zeros(v_inside_d, v_inside_d))) {
+        continue;
+      }
+
+      // The inverse mask indicates which of the MVs are outside
+      v_outside_d = _mm_xor_si128(v_inside_d, _mm_set1_epi8(0xff));
+      // Shift right to keep the sign bit clear, we will use this later
+      // to set the cost to the maximum value.
+      v_outside_d = _mm_srli_epi32(v_outside_d, 1);
+
+      // Compute the difference MV
+      v_diff_mv_w = _mm_sub_epi16(v_these_mv_clamp_w, vfcmv);
+      // We utilise the fact that the cost function is even, and use the
+      // absolute difference. This allows us to use unsigned indexes later
+      // and reduces cache pressure somewhat as only a half of the table
+      // is ever referenced.
+      v_diff_mv_w = _mm_abs_epi16(v_diff_mv_w);
+
+      // Compute the SIMD pointer offsets.
+      {
+#if ARCH_X86_64  //  sizeof(intptr_t) == 8
+        // Load the offsets (could use _mm_maskload_ps here, instead of the
+        // extra 'and' but it's slower that way)
+        __m128i v_bo10_q = _mm_load_si128((const __m128i*)&ss_os[i+0]);
+        __m128i v_bo32_q = _mm_load_si128((const __m128i*)&ss_os[i+2]);
+        // Set the ones falling outside to zero
+        v_bo10_q = _mm_and_si128(v_bo10_q,
+                                _mm_cvtepi32_epi64(v_inside_d));
+        v_bo32_q = _mm_and_si128(v_bo32_q,
+                                _mm_unpackhi_epi32(v_inside_d, v_inside_d));
+        // Compute the candidate addresses
+        v_blocka[0] = _mm_add_epi64(v_ba_q, v_bo10_q);
+        v_blocka[1] = _mm_add_epi64(v_ba_q, v_bo32_q);
+#else  // ARCH_X86 //  sizeof(intptr_t) == 4
+        __m128i v_bo_d = _mm_load_si128((const __m128i*)&ss_os[i]);
+        v_bo_d = _mm_and_si128(v_bo_d, v_inside_d);
+        v_blocka[0] = _mm_add_epi32(v_ba_d, v_bo_d);
+#endif
+      }
+
+      fn_ptr->sdx4df(what, what_stride,
+                    (const uint8_t **)&v_blocka[0], in_what_stride,
+                    (uint32_t*)&v_sad_d);
+
+      // Look up the component cost of the residual motion vector
+      {
+        const int32_t   row0 = _mm_extract_epi16(v_diff_mv_w, 0);
+        const int32_t   col0 = _mm_extract_epi16(v_diff_mv_w, 1);
+        const int32_t   row1 = _mm_extract_epi16(v_diff_mv_w, 2);
+        const int32_t   col1 = _mm_extract_epi16(v_diff_mv_w, 3);
+        const int32_t   row2 = _mm_extract_epi16(v_diff_mv_w, 4);
+        const int32_t   col2 = _mm_extract_epi16(v_diff_mv_w, 5);
+        const int32_t   row3 = _mm_extract_epi16(v_diff_mv_w, 6);
+        const int32_t   col3 = _mm_extract_epi16(v_diff_mv_w, 7);
+
+        // Note: This is a use case for vpgather in AVX2
+        const uint32_t cost0 = x->nmvsadcost[0][row0] + x->nmvsadcost[0][col0];
+        const uint32_t cost1 = x->nmvsadcost[0][row1] + x->nmvsadcost[0][col1];
+        const uint32_t cost2 = x->nmvsadcost[0][row2] + x->nmvsadcost[0][col2];
+        const uint32_t cost3 = x->nmvsadcost[0][row3] + x->nmvsadcost[0][col3];
+
+        __m128i v_cost_10_d;
+        __m128i v_cost_32_d;
+
+        v_cost_10_d = _mm_cvtsi32_si128(cost0);
+        v_cost_10_d = _mm_insert_epi32(v_cost_10_d, cost1, 1);
+
+        v_cost_32_d = _mm_cvtsi32_si128(cost2);
+        v_cost_32_d = _mm_insert_epi32(v_cost_32_d, cost3, 1);
+
+        v_cost_d = _mm_unpacklo_epi64(v_cost_10_d, v_cost_32_d);
+      }
+
+      // Now add in the joint cost
+      {
+        const __m128i v_sel_d = _mm_cmpeq_epi32(v_diff_mv_w,
+                                                _mm_setzero_si128());
+        const __m128i v_joint_cost_d = _mm_blendv_epi8(v_joint_cost_1_d,
+                                                       v_joint_cost_0_d,
+                                                       v_sel_d);
+        v_cost_d = _mm_add_epi32(v_cost_d, v_joint_cost_d);
+      }
+
+      // Multiply by sad_per_bit
+      v_cost_d = _mm_mullo_epi32(v_cost_d, v_spb_d);
+      // ROUND_POWER_OF_TWO(v_cost_d, 8)
+      v_cost_d = _mm_add_epi32(v_cost_d, _mm_set1_epi32(0x80));
+      v_cost_d = _mm_srai_epi32(v_cost_d, 8);
+      // Add the cost to the sad
+      v_sad_d = _mm_add_epi32(v_sad_d, v_cost_d);
+
+      // Make the motion vectors outside the search area have max cost
+      // by or'ing in the comparison mask, this way the minimum search won't
+      // pick them.
+      v_sad_d = _mm_or_si128(v_sad_d, v_outside_d);
+
+      // Find the minimum value and index horizontally in v_sad_d
+      {
+        // Try speculatively on 16 bits, so we can use the minpos intrinsic
+        const __m128i v_sad_w = _mm_packus_epi32(v_sad_d, v_sad_d);
+        const __m128i v_minp_w = _mm_minpos_epu16(v_sad_w);
+
+        uint32_t local_best_sad = _mm_extract_epi16(v_minp_w, 0);
+        uint32_t local_best_idx = _mm_extract_epi16(v_minp_w, 1);
+
+        // If the local best value is not saturated, just use it, otherwise
+        // find the horizontal minimum again the hard way on 32 bits.
+        // This is executed rarely.
+        if (__unlikely__(local_best_sad == 0xffff)) {
+          __m128i v_loval_d, v_hival_d, v_loidx_d, v_hiidx_d, v_sel_d;
+
+          v_loval_d = v_sad_d;
+          v_loidx_d = _mm_set_epi32(3, 2, 1, 0);
+          v_hival_d = _mm_srli_si128(v_loval_d, 8);
+          v_hiidx_d = _mm_srli_si128(v_loidx_d, 8);
+
+          v_sel_d = _mm_cmplt_epi32(v_hival_d, v_loval_d);
+
+          v_loval_d = _mm_blendv_epi8(v_loval_d, v_hival_d, v_sel_d);
+          v_loidx_d = _mm_blendv_epi8(v_loidx_d, v_hiidx_d, v_sel_d);
+          v_hival_d = _mm_srli_si128(v_loval_d, 4);
+          v_hiidx_d = _mm_srli_si128(v_loidx_d, 4);
+
+          v_sel_d = _mm_cmplt_epi32(v_hival_d, v_loval_d);
+
+          v_loval_d = _mm_blendv_epi8(v_loval_d, v_hival_d, v_sel_d);
+          v_loidx_d = _mm_blendv_epi8(v_loidx_d, v_hiidx_d, v_sel_d);
+
+          local_best_sad = _mm_extract_epi32(v_loval_d, 0);
+          local_best_idx = _mm_extract_epi32(v_loidx_d, 0);
+        }
+
+        // Update the global minimum if the local minimum is smaller
+        if (__likely__(local_best_sad < best_sad)) {
+          new_bmv = ((const int_mv *)&v_these_mv_w)[local_best_idx];
+          new_best_address  = ((const uint8_t **)v_blocka)[local_best_idx];
+
+          best_sad = local_best_sad;
+        }
+      }
+    }
+
+    bmv = new_bmv;
+    best_address = new_best_address;
+
+    v_bmv_w = _mm_set1_epi32(bmv.as_int);
+#if ARCH_X86_64
+    v_ba_q = _mm_set1_epi64x((intptr_t)best_address);
+#else
+    v_ba_d = _mm_set1_epi32((intptr_t)best_address);
+#endif
+
+    if (__unlikely__(best_address == in_what)) {
+      (*num00)++;
+    }
+  }
+
+  *best_mv = bmv.as_mv;
+  return best_sad;
+}

vp9/vp9cx.mk

@@ -96,6 +96,7 @@ VP9_CX_SRCS-yes += encoder/vp9_mbgraph.h
 VP9_CX_SRCS-$(HAVE_SSE2) += encoder/x86/vp9_avg_intrin_sse2.c
 VP9_CX_SRCS-$(HAVE_SSE2) += encoder/x86/vp9_temporal_filter_apply_sse2.asm
 VP9_CX_SRCS-$(HAVE_SSE2) += encoder/x86/vp9_quantize_sse2.c
+VP9_CX_SRCS-$(HAVE_AVX) += encoder/x86/vp9_diamond_search_sad_avx.c
 ifeq ($(CONFIG_VP9_HIGHBITDEPTH),yes)
 VP9_CX_SRCS-$(HAVE_SSE2) += encoder/x86/vp9_highbd_block_error_intrin_sse2.c
 endif