libvpx: Pull from upstream

source/libvpx/vp8/common/arm/neon/idct_dequant_0_2x_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>
+
+void idct_dequant_0_2x_neon(
+        int16_t *q,
+        int16_t dq,
+        unsigned char *dst,
+        int stride) {
+    unsigned char *dst0;
+    int i, a0, a1;
+    int16x8x2_t q2Add;
+    int32x2_t d2s32, d4s32;
+    uint8x8_t d2u8, d4u8;
+    uint16x8_t q1u16, q2u16;
+
+    a0 = ((q[0] * dq) + 4) >> 3;
+    a1 = ((q[16] * dq) + 4) >> 3;
+    q[0] = q[16] = 0;
+    q2Add.val[0] = vdupq_n_s16((int16_t)a0);
+    q2Add.val[1] = vdupq_n_s16((int16_t)a1);
+
+    for (i = 0; i < 2; i++, dst += 4) {
+        dst0 = dst;
+        d2s32 = vld1_lane_s32((const int32_t *)dst0, d2s32, 0);
+        dst0 += stride;
+        d2s32 = vld1_lane_s32((const int32_t *)dst0, d2s32, 1);
+        dst0 += stride;
+        d4s32 = vld1_lane_s32((const int32_t *)dst0, d4s32, 0);
+        dst0 += stride;
+        d4s32 = vld1_lane_s32((const int32_t *)dst0, d4s32, 1);
+
+        q1u16 = vaddw_u8(vreinterpretq_u16_s16(q2Add.val[i]),
+                         vreinterpret_u8_s32(d2s32));
+        q2u16 = vaddw_u8(vreinterpretq_u16_s16(q2Add.val[i]),
+                         vreinterpret_u8_s32(d4s32));
+
+        d2u8 = vqmovun_s16(vreinterpretq_s16_u16(q1u16));
+        d4u8 = vqmovun_s16(vreinterpretq_s16_u16(q2u16));
+
+        d2s32 = vreinterpret_s32_u8(d2u8);
+        d4s32 = vreinterpret_s32_u8(d4u8);
+
+        dst0 = dst;
+        vst1_lane_s32((int32_t *)dst0, d2s32, 0);
+        dst0 += stride;
+        vst1_lane_s32((int32_t *)dst0, d2s32, 1);
+        dst0 += stride;
+        vst1_lane_s32((int32_t *)dst0, d4s32, 0);
+        dst0 += stride;
+        vst1_lane_s32((int32_t *)dst0, d4s32, 1);
+    }
+    return;
+}