libvpx: Pull from upstream

source/libvpx/vp9/common/arm/neon/vp9_idct4x4_1_add_neon.c

+/*
+ *  Copyright (c) 2014 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 <arm_neon.h>
+#include "vp9/common/vp9_idct.h"
+
+void vp9_idct4x4_1_add_neon(
+        int16_t *input,
+        uint8_t *dest,
+        int dest_stride) {
+    uint8x8_t d6u8;
+    uint32x2_t d2u32 = vdup_n_u32(0);
+    uint16x8_t q8u16;
+    int16x8_t q0s16;
+    uint8_t *d1, *d2;
+    int16_t i, a1, cospi_16_64 = 11585;
+    int16_t out = dct_const_round_shift(input[0] * cospi_16_64);
+    out = dct_const_round_shift(out * cospi_16_64);
+    a1 = ROUND_POWER_OF_TWO(out, 4);
+
+    q0s16 = vdupq_n_s16(a1);
+
+    // dc_only_idct_add
+    d1 = d2 = dest;
+    for (i = 0; i < 2; i++) {
+        d2u32 = vld1_lane_u32((const uint32_t *)d1, d2u32, 0);
+        d1 += dest_stride;
+        d2u32 = vld1_lane_u32((const uint32_t *)d1, d2u32, 1);
+        d1 += dest_stride;
+
+        q8u16 = vaddw_u8(vreinterpretq_u16_s16(q0s16),
+                         vreinterpret_u8_u32(d2u32));
+        d6u8 = vqmovun_s16(vreinterpretq_s16_u16(q8u16));
+
+        vst1_lane_u32((uint32_t *)d2, vreinterpret_u32_u8(d6u8), 0);
+        d2 += dest_stride;
+        vst1_lane_u32((uint32_t *)d2, vreinterpret_u32_u8(d6u8), 1);
+        d2 += dest_stride;
+    }
+    return;
+}