libvpx: Pull from upstream

source/libvpx/vp9/common/arm/neon/vp9_idct16x16_neon.c

+/*
+ *  Copyright (c) 2013 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 "./vp9_rtcd.h"
+#include "vp9/common/vp9_common.h"
+
+extern void vp9_short_idct16x16_add_neon_pass1(int16_t *input,
+                                               int16_t *output,
+                                               int output_stride);
+extern void vp9_short_idct16x16_add_neon_pass2(int16_t *src,
+                                               int16_t *output,
+                                               int16_t *pass1Output,
+                                               int16_t skip_adding,
+                                               uint8_t *dest,
+                                               int dest_stride);
+extern void vp9_short_idct10_16x16_add_neon_pass1(int16_t *input,
+                                               int16_t *output,
+                                               int output_stride);
+extern void vp9_short_idct10_16x16_add_neon_pass2(int16_t *src,
+                                               int16_t *output,
+                                               int16_t *pass1Output,
+                                               int16_t skip_adding,
+                                               uint8_t *dest,
+                                               int dest_stride);
+extern void save_registers();
+extern void restore_registers();
+
+
+void vp9_short_idct16x16_add_neon(int16_t *input,
+                                  uint8_t *dest, int dest_stride) {
+  int16_t pass1_output[16*16] = {0};
+  int16_t row_idct_output[16*16] = {0};
+
+  // save d8-d15 register values.
+  save_registers();
+
+  /* Parallel idct on the upper 8 rows */
+  // First pass processes even elements 0, 2, 4, 6, 8, 10, 12, 14 and save the
+  // stage 6 result in pass1_output.
+  vp9_short_idct16x16_add_neon_pass1(input, pass1_output, 8);
+
+  // Second pass processes odd elements 1, 3, 5, 7, 9, 11, 13, 15 and combines
+  // with result in pass1(pass1_output) to calculate final result in stage 7
+  // which will be saved into row_idct_output.
+  vp9_short_idct16x16_add_neon_pass2(input+1,
+                                     row_idct_output,
+                                     pass1_output,
+                                     0,
+                                     dest,
+                                     dest_stride);
+
+  /* Parallel idct on the lower 8 rows */
+  // First pass processes even elements 0, 2, 4, 6, 8, 10, 12, 14 and save the
+  // stage 6 result in pass1_output.
+  vp9_short_idct16x16_add_neon_pass1(input+8*16, pass1_output, 8);
+
+  // Second pass processes odd elements 1, 3, 5, 7, 9, 11, 13, 15 and combines
+  // with result in pass1(pass1_output) to calculate final result in stage 7
+  // which will be saved into row_idct_output.
+  vp9_short_idct16x16_add_neon_pass2(input+8*16+1,
+                                     row_idct_output+8,
+                                     pass1_output,
+                                     0,
+                                     dest,
+                                     dest_stride);
+
+  /* Parallel idct on the left 8 columns */
+  // First pass processes even elements 0, 2, 4, 6, 8, 10, 12, 14 and save the
+  // stage 6 result in pass1_output.
+  vp9_short_idct16x16_add_neon_pass1(row_idct_output, pass1_output, 8);
+
+  // Second pass processes odd elements 1, 3, 5, 7, 9, 11, 13, 15 and combines
+  // with result in pass1(pass1_output) to calculate final result in stage 7.
+  // Then add the result to the destination data.
+  vp9_short_idct16x16_add_neon_pass2(row_idct_output+1,
+                                     row_idct_output,
+                                     pass1_output,
+                                     1,
+                                     dest,
+                                     dest_stride);
+
+  /* Parallel idct on the right 8 columns */
+  // First pass processes even elements 0, 2, 4, 6, 8, 10, 12, 14 and save the
+  // stage 6 result in pass1_output.
+  vp9_short_idct16x16_add_neon_pass1(row_idct_output+8*16, pass1_output, 8);
+
+  // Second pass processes odd elements 1, 3, 5, 7, 9, 11, 13, 15 and combines
+  // with result in pass1(pass1_output) to calculate final result in stage 7.
+  // Then add the result to the destination data.
+  vp9_short_idct16x16_add_neon_pass2(row_idct_output+8*16+1,
+                                     row_idct_output+8,
+                                     pass1_output,
+                                     1,
+                                     dest+8,
+                                     dest_stride);
+
+  // restore d8-d15 register values.
+  restore_registers();
+
+  return;
+}
+
+void vp9_short_idct10_16x16_add_neon(int16_t *input,
+                                  uint8_t *dest, int dest_stride) {
+  int16_t pass1_output[16*16] = {0};
+  int16_t row_idct_output[16*16] = {0};
+
+  // save d8-d15 register values.
+  save_registers();
+
+  /* Parallel idct on the upper 8 rows */
+  // First pass processes even elements 0, 2, 4, 6, 8, 10, 12, 14 and save the
+  // stage 6 result in pass1_output.
+  vp9_short_idct10_16x16_add_neon_pass1(input, pass1_output, 8);
+
+  // Second pass processes odd elements 1, 3, 5, 7, 9, 11, 13, 15 and combines
+  // with result in pass1(pass1_output) to calculate final result in stage 7
+  // which will be saved into row_idct_output.
+  vp9_short_idct10_16x16_add_neon_pass2(input+1,
+                                        row_idct_output,
+                                        pass1_output,
+                                        0,
+                                        dest,
+                                        dest_stride);
+
+  /* Skip Parallel idct on the lower 8 rows as they are all 0s */
+
+  /* Parallel idct on the left 8 columns */
+  // First pass processes even elements 0, 2, 4, 6, 8, 10, 12, 14 and save the
+  // stage 6 result in pass1_output.
+  vp9_short_idct16x16_add_neon_pass1(row_idct_output, pass1_output, 8);
+
+  // Second pass processes odd elements 1, 3, 5, 7, 9, 11, 13, 15 and combines
+  // with result in pass1(pass1_output) to calculate final result in stage 7.
+  // Then add the result to the destination data.
+  vp9_short_idct16x16_add_neon_pass2(row_idct_output+1,
+                                     row_idct_output,
+                                     pass1_output,
+                                     1,
+                                     dest,
+                                     dest_stride);
+
+  /* Parallel idct on the right 8 columns */
+  // First pass processes even elements 0, 2, 4, 6, 8, 10, 12, 14 and save the
+  // stage 6 result in pass1_output.
+  vp9_short_idct16x16_add_neon_pass1(row_idct_output+8*16, pass1_output, 8);
+
+  // Second pass processes odd elements 1, 3, 5, 7, 9, 11, 13, 15 and combines
+  // with result in pass1(pass1_output) to calculate final result in stage 7.
+  // Then add the result to the destination data.
+  vp9_short_idct16x16_add_neon_pass2(row_idct_output+8*16+1,
+                                     row_idct_output+8,
+                                     pass1_output,
+                                     1,
+                                     dest+8,
+                                     dest_stride);
+
+  // restore d8-d15 register values.
+  restore_registers();
+
+  return;
+}