libvpx: Pull from upstream

source/libvpx/vp8/common/arm/neon/idct_dequant_full_2x_neon.c

Index: source/libvpx/vp8/common/arm/neon/idct_dequant_full_2x_neon.c
===================================================================
--- source/libvpx/vp8/common/arm/neon/idct_dequant_full_2x_neon.c	(revision 0)
+++ source/libvpx/vp8/common/arm/neon/idct_dequant_full_2x_neon.c	(revision 0)
@@ -0,0 +1,185 @@
+/*
+ *  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>
+
+static const int16_t cospi8sqrt2minus1 = 20091;
+static const int16_t sinpi8sqrt2       = 17734;
+// because the lowest bit in 0x8a8c is 0, we can pre-shift this
+
+void idct_dequant_full_2x_neon(
+        int16_t *q,
+        int16_t *dq,
+        unsigned char *dst,
+        int stride) {
+    unsigned char *dst0, *dst1;
+    int32x2_t d28, d29, d30, d31;
+    int16x8_t q0, q1, q2, q3, q4, q5, q6, q7, q8, q9, q10, q11;
+    int16x8_t qEmpty = vdupq_n_s16(0);
+    int32x4x2_t q2tmp0, q2tmp1;
+    int16x8x2_t q2tmp2, q2tmp3;
+    int16x4_t dLow0, dLow1, dHigh0, dHigh1;
+
+    d28 = d29 = d30 = d31 = vdup_n_s32(0);
+
+    // load dq
+    q0 = vld1q_s16(dq);
+    dq += 8;
+    q1 = vld1q_s16(dq);
+
+    // load q
+    q2 = vld1q_s16(q);
+    vst1q_s16(q, qEmpty);
+    q += 8;
+    q3 = vld1q_s16(q);
+    vst1q_s16(q, qEmpty);
+    q += 8;
+    q4 = vld1q_s16(q);
+    vst1q_s16(q, qEmpty);
+    q += 8;
+    q5 = vld1q_s16(q);
+    vst1q_s16(q, qEmpty);
+
+    // load src from dst
+    dst0 = dst;
+    dst1 = dst + 4;
+    d28 = vld1_lane_s32((const int32_t *)dst0, d28, 0);
+    dst0 += stride;
+    d28 = vld1_lane_s32((const int32_t *)dst1, d28, 1);
+    dst1 += stride;
+    d29 = vld1_lane_s32((const int32_t *)dst0, d29, 0);
+    dst0 += stride;
+    d29 = vld1_lane_s32((const int32_t *)dst1, d29, 1);
+    dst1 += stride;
+
+    d30 = vld1_lane_s32((const int32_t *)dst0, d30, 0);
+    dst0 += stride;
+    d30 = vld1_lane_s32((const int32_t *)dst1, d30, 1);
+    dst1 += stride;
+    d31 = vld1_lane_s32((const int32_t *)dst0, d31, 0);
+    d31 = vld1_lane_s32((const int32_t *)dst1, d31, 1);
+
+    q2 = vmulq_s16(q2, q0);
+    q3 = vmulq_s16(q3, q1);
+    q4 = vmulq_s16(q4, q0);
+    q5 = vmulq_s16(q5, q1);
+
+    // vswp
+    dLow0 = vget_low_s16(q2);
+    dHigh0 = vget_high_s16(q2);
+    dLow1 = vget_low_s16(q4);
+    dHigh1 = vget_high_s16(q4);
+    q2 = vcombine_s16(dLow0, dLow1);
+    q4 = vcombine_s16(dHigh0, dHigh1);
+
+    dLow0 = vget_low_s16(q3);
+    dHigh0 = vget_high_s16(q3);
+    dLow1 = vget_low_s16(q5);
+    dHigh1 = vget_high_s16(q5);
+    q3 = vcombine_s16(dLow0, dLow1);
+    q5 = vcombine_s16(dHigh0, dHigh1);
+
+    q6 = vqdmulhq_n_s16(q4, sinpi8sqrt2);
+    q7 = vqdmulhq_n_s16(q5, sinpi8sqrt2);
+    q8 = vqdmulhq_n_s16(q4, cospi8sqrt2minus1);
+    q9 = vqdmulhq_n_s16(q5, cospi8sqrt2minus1);
+
+    q10 = vqaddq_s16(q2, q3);
+    q11 = vqsubq_s16(q2, q3);
+
+    q8 = vshrq_n_s16(q8, 1);
+    q9 = vshrq_n_s16(q9, 1);
+
+    q4 = vqaddq_s16(q4, q8);
+    q5 = vqaddq_s16(q5, q9);
+
+    q2 = vqsubq_s16(q6, q5);
+    q3 = vqaddq_s16(q7, q4);
+
+    q4 = vqaddq_s16(q10, q3);
+    q5 = vqaddq_s16(q11, q2);
+    q6 = vqsubq_s16(q11, q2);
+    q7 = vqsubq_s16(q10, q3);
+
+    q2tmp0 = vtrnq_s32(vreinterpretq_s32_s16(q4), vreinterpretq_s32_s16(q6));
+    q2tmp1 = vtrnq_s32(vreinterpretq_s32_s16(q5), vreinterpretq_s32_s16(q7));
+    q2tmp2 = vtrnq_s16(vreinterpretq_s16_s32(q2tmp0.val[0]),
+                       vreinterpretq_s16_s32(q2tmp1.val[0]));
+    q2tmp3 = vtrnq_s16(vreinterpretq_s16_s32(q2tmp0.val[1]),
+                       vreinterpretq_s16_s32(q2tmp1.val[1]));
+
+    // loop 2
+    q8  = vqdmulhq_n_s16(q2tmp2.val[1], sinpi8sqrt2);
+    q9  = vqdmulhq_n_s16(q2tmp3.val[1], sinpi8sqrt2);
+    q10 = vqdmulhq_n_s16(q2tmp2.val[1], cospi8sqrt2minus1);
+    q11 = vqdmulhq_n_s16(q2tmp3.val[1], cospi8sqrt2minus1);
+
+    q2 = vqaddq_s16(q2tmp2.val[0], q2tmp3.val[0]);
+    q3 = vqsubq_s16(q2tmp2.val[0], q2tmp3.val[0]);
+
+    q10 = vshrq_n_s16(q10, 1);
+    q11 = vshrq_n_s16(q11, 1);
+
+    q10 = vqaddq_s16(q2tmp2.val[1], q10);
+    q11 = vqaddq_s16(q2tmp3.val[1], q11);
+
+    q8 = vqsubq_s16(q8, q11);
+    q9 = vqaddq_s16(q9, q10);
+
+    q4 = vqaddq_s16(q2, q9);
+    q5 = vqaddq_s16(q3, q8);
+    q6 = vqsubq_s16(q3, q8);
+    q7 = vqsubq_s16(q2, q9);
+
+    q4 = vrshrq_n_s16(q4, 3);
+    q5 = vrshrq_n_s16(q5, 3);
+    q6 = vrshrq_n_s16(q6, 3);
+    q7 = vrshrq_n_s16(q7, 3);
+
+    q2tmp0 = vtrnq_s32(vreinterpretq_s32_s16(q4), vreinterpretq_s32_s16(q6));
+    q2tmp1 = vtrnq_s32(vreinterpretq_s32_s16(q5), vreinterpretq_s32_s16(q7));
+    q2tmp2 = vtrnq_s16(vreinterpretq_s16_s32(q2tmp0.val[0]),
+                       vreinterpretq_s16_s32(q2tmp1.val[0]));
+    q2tmp3 = vtrnq_s16(vreinterpretq_s16_s32(q2tmp0.val[1]),
+                       vreinterpretq_s16_s32(q2tmp1.val[1]));
+
+    q4 = vreinterpretq_s16_u16(vaddw_u8(vreinterpretq_u16_s16(q2tmp2.val[0]),
+                                          vreinterpret_u8_s32(d28)));
+    q5 = vreinterpretq_s16_u16(vaddw_u8(vreinterpretq_u16_s16(q2tmp2.val[1]),
+                                          vreinterpret_u8_s32(d29)));
+    q6 = vreinterpretq_s16_u16(vaddw_u8(vreinterpretq_u16_s16(q2tmp3.val[0]),
+                                          vreinterpret_u8_s32(d30)));
+    q7 = vreinterpretq_s16_u16(vaddw_u8(vreinterpretq_u16_s16(q2tmp3.val[1]),
+                                          vreinterpret_u8_s32(d31)));
+
+    d28 = vreinterpret_s32_u8(vqmovun_s16(q4));
+    d29 = vreinterpret_s32_u8(vqmovun_s16(q5));
+    d30 = vreinterpret_s32_u8(vqmovun_s16(q6));
+    d31 = vreinterpret_s32_u8(vqmovun_s16(q7));
+
+    dst0 = dst;
+    dst1 = dst + 4;
+    vst1_lane_s32((int32_t *)dst0, d28, 0);
+    dst0 += stride;
+    vst1_lane_s32((int32_t *)dst1, d28, 1);
+    dst1 += stride;
+    vst1_lane_s32((int32_t *)dst0, d29, 0);
+    dst0 += stride;
+    vst1_lane_s32((int32_t *)dst1, d29, 1);
+    dst1 += stride;
+
+    vst1_lane_s32((int32_t *)dst0, d30, 0);
+    dst0 += stride;
+    vst1_lane_s32((int32_t *)dst1, d30, 1);
+    dst1 += stride;
+    vst1_lane_s32((int32_t *)dst0, d31, 0);
+    vst1_lane_s32((int32_t *)dst1, d31, 1);
+    return;
+}