libvpx: Pull from upstream

source/libvpx/vp8/encoder/arm/neon/vp8_shortwalsh4x4_neon.c

Index: source/libvpx/vp8/encoder/arm/neon/vp8_shortwalsh4x4_neon.c
===================================================================
--- source/libvpx/vp8/encoder/arm/neon/vp8_shortwalsh4x4_neon.c	(revision 0)
+++ source/libvpx/vp8/encoder/arm/neon/vp8_shortwalsh4x4_neon.c	(revision 0)
@@ -0,0 +1,118 @@
+/*
+ *  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 vp8_short_walsh4x4_neon(
+        int16_t *input,
+        int16_t *output,
+        int pitch) {
+    uint16x4_t d16u16;
+    int16x8_t q0s16, q1s16;
+    int16x4_t dEmptys16, d0s16, d1s16, d2s16, d3s16, d4s16, d5s16, d6s16, d7s16;
+    int32x4_t qEmptys32, q0s32, q1s32, q2s32, q3s32, q8s32;
+    int32x4_t q9s32, q10s32, q11s32, q15s32;
+    uint32x4_t q8u32, q9u32, q10u32, q11u32;
+    int16x4x2_t v2tmp0, v2tmp1;
+    int32x2x2_t v2tmp2, v2tmp3;
+
+    dEmptys16 = vdup_n_s16(0);
+    qEmptys32 = vdupq_n_s32(0);
+    q15s32 = vdupq_n_s32(3);
+
+    d0s16 = vld1_s16(input);
+    input += pitch/2;
+    d1s16 = vld1_s16(input);
+    input += pitch/2;
+    d2s16 = vld1_s16(input);
+    input += pitch/2;
+    d3s16 = vld1_s16(input);
+
+    v2tmp2 = vtrn_s32(vreinterpret_s32_s16(d0s16),
+                      vreinterpret_s32_s16(d2s16));
+    v2tmp3 = vtrn_s32(vreinterpret_s32_s16(d1s16),
+                      vreinterpret_s32_s16(d3s16));
+    v2tmp0 = vtrn_s16(vreinterpret_s16_s32(v2tmp2.val[0]),   // d0
+                      vreinterpret_s16_s32(v2tmp3.val[0]));  // d1
+    v2tmp1 = vtrn_s16(vreinterpret_s16_s32(v2tmp2.val[1]),   // d2
+                      vreinterpret_s16_s32(v2tmp3.val[1]));  // d3
+
+    d4s16 = vadd_s16(v2tmp0.val[0], v2tmp1.val[0]);
+    d5s16 = vadd_s16(v2tmp0.val[1], v2tmp1.val[1]);
+    d6s16 = vsub_s16(v2tmp0.val[1], v2tmp1.val[1]);
+    d7s16 = vsub_s16(v2tmp0.val[0], v2tmp1.val[0]);
+
+    d4s16 = vshl_n_s16(d4s16, 2);
+    d5s16 = vshl_n_s16(d5s16, 2);
+    d6s16 = vshl_n_s16(d6s16, 2);
+    d7s16 = vshl_n_s16(d7s16, 2);
+
+    d16u16 = vceq_s16(d4s16, dEmptys16);
+    d16u16 = vmvn_u16(d16u16);
+
+    d0s16 = vadd_s16(d4s16, d5s16);
+    d3s16 = vsub_s16(d4s16, d5s16);
+    d1s16 = vadd_s16(d7s16, d6s16);
+    d2s16 = vsub_s16(d7s16, d6s16);
+
+    d0s16 = vsub_s16(d0s16, vreinterpret_s16_u16(d16u16));
+
+    // Second for-loop
+    v2tmp2 = vtrn_s32(vreinterpret_s32_s16(d1s16),
+                      vreinterpret_s32_s16(d3s16));
+    v2tmp3 = vtrn_s32(vreinterpret_s32_s16(d0s16),
+                      vreinterpret_s32_s16(d2s16));
+    v2tmp0 = vtrn_s16(vreinterpret_s16_s32(v2tmp3.val[1]),   // d2
+                      vreinterpret_s16_s32(v2tmp2.val[1]));  // d3
+    v2tmp1 = vtrn_s16(vreinterpret_s16_s32(v2tmp3.val[0]),   // d0
+                      vreinterpret_s16_s32(v2tmp2.val[0]));  // d1
+
+    q8s32  = vaddl_s16(v2tmp1.val[0], v2tmp0.val[0]);
+    q9s32  = vaddl_s16(v2tmp1.val[1], v2tmp0.val[1]);
+    q10s32 = vsubl_s16(v2tmp1.val[1], v2tmp0.val[1]);
+    q11s32 = vsubl_s16(v2tmp1.val[0], v2tmp0.val[0]);
+
+    q0s32 = vaddq_s32(q8s32, q9s32);
+    q1s32 = vaddq_s32(q11s32, q10s32);
+    q2s32 = vsubq_s32(q11s32, q10s32);
+    q3s32 = vsubq_s32(q8s32, q9s32);
+
+    q8u32  = vcltq_s32(q0s32, qEmptys32);
+    q9u32  = vcltq_s32(q1s32, qEmptys32);
+    q10u32 = vcltq_s32(q2s32, qEmptys32);
+    q11u32 = vcltq_s32(q3s32, qEmptys32);
+
+    q8s32  = vreinterpretq_s32_u32(q8u32);
+    q9s32  = vreinterpretq_s32_u32(q9u32);
+    q10s32 = vreinterpretq_s32_u32(q10u32);
+    q11s32 = vreinterpretq_s32_u32(q11u32);
+
+    q0s32 = vsubq_s32(q0s32, q8s32);
+    q1s32 = vsubq_s32(q1s32, q9s32);
+    q2s32 = vsubq_s32(q2s32, q10s32);
+    q3s32 = vsubq_s32(q3s32, q11s32);
+
+    q8s32  = vaddq_s32(q0s32, q15s32);
+    q9s32  = vaddq_s32(q1s32, q15s32);
+    q10s32 = vaddq_s32(q2s32, q15s32);
+    q11s32 = vaddq_s32(q3s32, q15s32);
+
+    d0s16 = vshrn_n_s32(q8s32, 3);
+    d1s16 = vshrn_n_s32(q9s32, 3);
+    d2s16 = vshrn_n_s32(q10s32, 3);
+    d3s16 = vshrn_n_s32(q11s32, 3);
+
+    q0s16 = vcombine_s16(d0s16, d1s16);
+    q1s16 = vcombine_s16(d2s16, d3s16);
+
+    vst1q_s16(output, q0s16);
+    vst1q_s16(output + 8, q1s16);
+    return;
+}