From 4e4084434e5fe834fc625a06b77496050e53dfdb Mon Sep 17 00:00:00 2001
From: Joose Sainio <joose.sainio@tuni.fi>
Date: Tue, 12 Sep 2023 14:48:33 +0300
Subject: [PATCH] Remove setr from the loop in hor_w4

---
 src/strategies/avx2/intra-avx2.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/strategies/avx2/intra-avx2.c b/src/strategies/avx2/intra-avx2.c
index 17f63414..9c6f8cb8 100644
--- a/src/strategies/avx2/intra-avx2.c
+++ b/src/strategies/avx2/intra-avx2.c
@@ -701,12 +701,16 @@ static void intra_pred_planar_hor_w4(const uvg_pixel* ref, const int line, const
   __m256i v_last_ref_coeff = _mm256_setr_epi16(1, 2, 3, 4, 1, 2, 3, 4, 1, 2, 3, 4, 1, 2, 3, 4);
 
   __m256i v_last_ref_mul = _mm256_mullo_epi16(v_last_ref, v_last_ref_coeff);
+  __m256i shuffle_mask = _mm256_setr_epi8(0, -1, 0, -1, 0, -1, 0, -1, 8, -1, 8, -1, 8, -1, 8, -1, 0, -1, 0, -1, 0, -1, 0, -1, 8, -1, 8, -1, 8, -1, 8, -1);
 
   for (int i = 0, d = 0; i < line; i += 4, ++d) {
     // Handle 4 lines at a time
-    // TODO: setr is VERY SLOW, replace this
-    __m256i v_ref = _mm256_setr_epi16(ref[i + 1], ref[i + 1], ref[i + 1], ref[i + 1], ref[i + 2], ref[i + 2], ref[i + 2], ref[i + 2], 
-                                      ref[i + 3], ref[i + 3], ref[i + 3], ref[i + 3], ref[i + 4], ref[i + 4], ref[i + 4], ref[i + 4]);
+    // | ref1 | ref2 | ref3 | ref4 | Don't care
+    __m128i v_ref_0 = _mm_loadu_si128((__m128i const*)& ref[i + 1]);
+    // | ref1 | 0 * 7 | ref2 | 0 * 7 | ref3 | 0 * 7 | ref4 | 0* 7 |
+    __m256i v_ref = _mm256_cvtepu8_epi64(v_ref_0);
+    // | ref1_l | ref1_h | ref1_l | ref1_h | ... 
+    v_ref = _mm256_shuffle_epi8(v_ref, shuffle_mask);
 
     __m256i v_tmp = _mm256_mullo_epi16(v_ref, v_ref_coeff);