Libyuv MIPS DSPR2 optimizations.

source/scale_mips.cc

 /*
  *  Copyright 2012 The LibYuv 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.
  */
 
@@ skipping 24 matching lines @@
       "1:                                            \n"
       "lw             $t0, 0(%[src_ptr])             \n"  // |3|2|1|0|
       "lw             $t1, 4(%[src_ptr])             \n"  // |7|6|5|4|
       "lw             $t2, 8(%[src_ptr])             \n"  // |11|10|9|8|
       "lw             $t3, 12(%[src_ptr])            \n"  // |15|14|13|12|
       "lw             $t4, 16(%[src_ptr])            \n"  // |19|18|17|16|
       "lw             $t5, 20(%[src_ptr])            \n"  // |23|22|21|20|
       "lw             $t6, 24(%[src_ptr])            \n"  // |27|26|25|24|
       "lw             $t7, 28(%[src_ptr])            \n"  // |31|30|29|28|
       // TODO(fbarchard): Use odd pixels instead of even.
-      "precr.qb.ph    $t8, $t1, $t0                  \n"  // |6|4|2|0|
-      "precr.qb.ph    $t0, $t3, $t2                  \n"  // |14|12|10|8|
-      "precr.qb.ph    $t1, $t5, $t4                  \n"  // |22|20|18|16|
-      "precr.qb.ph    $t2, $t7, $t6                  \n"  // |30|28|26|24|
+      "precrq.qb.ph   $t8, $t1, $t0                  \n"  // |7|5|3|1|
+      "precrq.qb.ph   $t0, $t3, $t2                  \n"  // |15|13|11|9|
+      "precrq.qb.ph   $t1, $t5, $t4                  \n"  // |23|21|19|17|
+      "precrq.qb.ph   $t2, $t7, $t6                  \n"  // |31|29|27|25|
       "addiu          %[src_ptr], %[src_ptr], 32     \n"
       "addiu          $t9, $t9, -1                   \n"
       "sw             $t8, 0(%[dst])                 \n"
       "sw             $t0, 4(%[dst])                 \n"
       "sw             $t1, 8(%[dst])                 \n"
       "sw             $t2, 12(%[dst])                \n"
       "bgtz           $t9, 1b                        \n"
       " addiu         %[dst], %[dst], 16             \n"
 
       "2:                                            \n"
       "andi           $t9, %[dst_width], 0xf         \n"  // residue
       "beqz           $t9, 3f                        \n"
       " nop                                          \n"
 
       "21:                                           \n"
-      "lbu            $t0, 0(%[src_ptr])             \n"
+      "lbu            $t0, 1(%[src_ptr])             \n"
       "addiu          %[src_ptr], %[src_ptr], 2      \n"
       "addiu          $t9, $t9, -1                   \n"
       "sb             $t0, 0(%[dst])                 \n"
       "bgtz           $t9, 21b                       \n"
       " addiu         %[dst], %[dst], 1              \n"
 
       "3:                                            \n"
       ".set pop                                      \n"
       : [src_ptr] "+r"(src_ptr), [dst] "+r"(dst)
       : [dst_width] "r"(dst_width)
@@ skipping 116 matching lines @@
       "lw             $t3, 8(%[src_ptr])            \n"  // |11|10|9|8|
       "lw             $t4, 12(%[src_ptr])           \n"  // |15|14|13|12|
       "lw             $t5, 16(%[src_ptr])           \n"  // |19|18|17|16|
       "lw             $t6, 20(%[src_ptr])           \n"  // |23|22|21|20|
       "lw             $t7, 24(%[src_ptr])           \n"  // |27|26|25|24|
       "lw             $t8, 28(%[src_ptr])           \n"  // |31|30|29|28|
       "precr.qb.ph    $t1, $t2, $t1                 \n"  // |6|4|2|0|
       "precr.qb.ph    $t2, $t4, $t3                 \n"  // |14|12|10|8|
       "precr.qb.ph    $t5, $t6, $t5                 \n"  // |22|20|18|16|
       "precr.qb.ph    $t6, $t8, $t7                 \n"  // |30|28|26|24|
-      "precr.qb.ph    $t1, $t2, $t1                 \n"  // |12|8|4|0|
-      "precr.qb.ph    $t5, $t6, $t5                 \n"  // |28|24|20|16|
+      "precrq.qb.ph   $t1, $t2, $t1                 \n"  // |14|10|6|2|
+      "precrq.qb.ph   $t5, $t6, $t5                 \n"  // |30|26|22|18|
       "addiu          %[src_ptr], %[src_ptr], 32    \n"
       "addiu          $t9, $t9, -1                  \n"
       "sw             $t1, 0(%[dst])                \n"
       "sw             $t5, 4(%[dst])                \n"
       "bgtz           $t9, 1b                       \n"
       " addiu         %[dst], %[dst], 8             \n"
 
       "2:                                           \n"
       "andi           $t9, %[dst_width], 7          \n"  // residue
       "beqz           $t9, 3f                       \n"
       " nop                                         \n"
 
       "21:                                          \n"
-      "lbu            $t1, 0(%[src_ptr])            \n"
+      "lbu            $t1, 2(%[src_ptr])            \n"
       "addiu          %[src_ptr], %[src_ptr], 4     \n"
       "addiu          $t9, $t9, -1                  \n"
       "sb             $t1, 0(%[dst])                \n"
       "bgtz           $t9, 21b                      \n"
       " addiu         %[dst], %[dst], 1             \n"
 
       "3:                                           \n"
       ".set pop                                     \n"
       : [src_ptr] "+r"(src_ptr), [dst] "+r"(dst)
       : [dst_width] "r"(dst_width)
@@ skipping 381 matching lines @@
       "sb              $t7, -2(%[dst_ptr])               \n"
       "bgtz            %[dst_width], 1b                  \n"
       " sb             $t0, -3(%[dst_ptr])               \n"
       ".set pop                                          \n"
       : [src_ptr] "+r"(src_ptr), [dst_ptr] "+r"(dst_ptr), [s1] "+r"(s1),
         [s2] "+r"(s2), [dst_width] "+r"(dst_width)
       : [c1] "r"(c1), [c2] "r"(c2)
       : "t0", "t1", "t2", "t3", "t4", "t5", "t6", "t7", "t8");
 }
 
+void ScaleAddRow_DSPR2(const uint8* src_ptr, uint16* dst_ptr, int src_width) {
+  int x;
+  for (x = 0; x < ((src_width - 1)); x += 8) {
+    uint32 tmp_t1, tmp_t2, tmp_t3, tmp_t4;
+    uint32 tmp_t5, tmp_t6, tmp_t7, tmp_t8;
+    __asm__ __volatile__(
+        ".set push                                                \n"
+        ".set noreorder                                           \n"
+        "lw                %[tmp_t5],   0(%[src_ptr])             \n"
+        "lw                %[tmp_t6],   4(%[src_ptr])             \n"
+        "lw                %[tmp_t1],   0(%[dst_ptr])             \n"
+        "lw                %[tmp_t2],   4(%[dst_ptr])             \n"
+        "lw                %[tmp_t3],   8(%[dst_ptr])             \n"
+        "lw                %[tmp_t4],   12(%[dst_ptr])            \n"
+        "preceu.ph.qbr     %[tmp_t7],   %[tmp_t5]                 \n"
+        "preceu.ph.qbl     %[tmp_t8],   %[tmp_t5]                 \n"
+        "addu.ph           %[tmp_t1],   %[tmp_t1],     %[tmp_t7]  \n"
+        "addu.ph           %[tmp_t2],   %[tmp_t2],     %[tmp_t8]  \n"
+        "preceu.ph.qbr     %[tmp_t7],   %[tmp_t6]                 \n"
+        "preceu.ph.qbl     %[tmp_t8],   %[tmp_t6]                 \n"
+        "addu.ph           %[tmp_t3],   %[tmp_t3],     %[tmp_t7]  \n"
+        "addu.ph           %[tmp_t4],   %[tmp_t4],     %[tmp_t8]  \n"
+        "sw                %[tmp_t1],   0(%[dst_ptr])             \n"
+        "sw                %[tmp_t2],   4(%[dst_ptr])             \n"
+        "sw                %[tmp_t3],   8(%[dst_ptr])             \n"
+        "sw                %[tmp_t4],   12(%[dst_ptr])            \n"
+        ".set pop                                                 \n"
+        :
+        [tmp_t1] "=&r"(tmp_t1), [tmp_t2] "=&r"(tmp_t2), [tmp_t3] "=&r"(tmp_t3),
+        [tmp_t4] "=&r"(tmp_t4), [tmp_t5] "=&r"(tmp_t5), [tmp_t6] "=&r"(tmp_t6),
+        [tmp_t7] "=&r"(tmp_t7), [tmp_t8] "=&r"(tmp_t8), [src_ptr] "+r"(src_ptr)
+        : [dst_ptr] "r"(dst_ptr));
+    src_ptr += 8;
+    dst_ptr += 8;
+  }
+
+  if ((src_width)&7) {
+    for (x = 0; x < ((src_width - 1) & 7); x += 1) {
+      dst_ptr[0] += src_ptr[0];
+      src_ptr += 1;
+      dst_ptr += 1;
+    }
+  }
+}
+
 #endif  // defined(__mips_dsp) && (__mips_dsp_rev >= 2)
 
 #ifdef __cplusplus
 }  // extern "C"
 }  // namespace libyuv
 #endif