From 53c8434398b3cba7ac6298cdd44abd40f0e640b1 Mon Sep 17 00:00:00 2001 From: Stephan Walter Date: Sun, 23 Apr 2023 11:01:03 +0000 Subject: [PATCH] Improve AVX2 for vec_dot_q4_3_q8_0 (#1138) --- ggml.c | 14 +++++--------- 1 file changed, 5 insertions(+), 9 deletions(-) diff --git a/ggml.c b/ggml.c index 3c45c5e9d..3ee2d0814 100644 --- a/ggml.c +++ b/ggml.c @@ -2947,6 +2947,7 @@ static void ggml_vec_dot_q4_3_q8_0(const int n, float * restrict s, const void * #elif defined(__AVX2__) // Initialize accumulator with zeros __m256 acc = _mm256_setzero_ps(); + float summs = 0.0f; // Main loop for (int i = 0; i < nb; i++) { @@ -2954,9 +2955,8 @@ static void ggml_vec_dot_q4_3_q8_0(const int n, float * restrict s, const void * const __m128 d1 = _mm_set1_ps(GGML_FP16_TO_FP32(x[2*i + 1].d)); const __m256 dx = _mm256_set_m128(d1, d0); - const __m128 m0 = _mm_set1_ps(GGML_FP16_TO_FP32(x[2*i + 0].m)); - const __m128 m1 = _mm_set1_ps(GGML_FP16_TO_FP32(x[2*i + 1].m)); - const __m256 mx = _mm256_set_m128(m1, m0); + summs += GGML_FP16_TO_FP32(x[2*i + 0].m) * y[i].s0 + + GGML_FP16_TO_FP32(x[2*i + 1].m) * y[i].s1; const __m128i bx0 = bytes_from_nibbles_16(x[2*i + 0].qs); const __m128i bx1 = bytes_from_nibbles_16(x[2*i + 1].qs); @@ -2965,16 +2965,12 @@ static void ggml_vec_dot_q4_3_q8_0(const int n, float * restrict s, const void * const __m256 dy = _mm256_broadcast_ss(&y[i].d); const __m256i by = _mm256_loadu_si256((const __m256i *)y[i].qs); - const __m256i syi = _mm256_maddubs_epi16(_mm256_set1_epi8(1), by); - const __m256 syf = sum_i16_pairs_float(syi); - const __m256 q = mul_sum_i8_pairs_float(bx, by); - const __m256 sxy = _mm256_fmadd_ps(q, dx, _mm256_mul_ps(mx, syf)); - acc = _mm256_fmadd_ps(sxy, dy, acc); + acc = _mm256_fmadd_ps(q, _mm256_mul_ps(dx, dy), acc); } - *s = hsum_float_8(acc); + *s = hsum_float_8(acc) + summs; #else // scalar float sumf = 0.0;