From dcdd65e2969bc03c91a1ebd1160162d5054e6923 Mon Sep 17 00:00:00 2001 From: Georgi Gerganov Date: Tue, 18 Apr 2023 22:59:17 +0300 Subject: ggml : optimize ggml_vec_dot_q4_0_q8_0() using vectorized accumulators --- ggml.c | 39 +++++++++++++++++++-------------------- 1 file changed, 19 insertions(+), 20 deletions(-) diff --git a/ggml.c b/ggml.c index acdba03..66a8c5b 100644 --- a/ggml.c +++ b/ggml.c @@ -2766,8 +2766,8 @@ static void ggml_vec_dot_q4_0_q8_0(const int n, float * restrict s, const void * float sumf = 0.0; #if defined(__ARM_NEON) - float sum0 = 0.0f; - float sum1 = 0.0f; + float32x4_t sumv0 = vdupq_n_f32(0.0f); + float32x4_t sumv1 = vdupq_n_f32(0.0f); for (int i = 0; i < nb; i += 2) { const block_q4_0 * restrict x0 = &x[i + 0]; @@ -2807,14 +2807,17 @@ static void ggml_vec_dot_q4_0_q8_0(const int n, float * restrict s, const void * #if defined(__ARM_FEATURE_DOTPROD) // dot product into int32x4_t - int32x4_t p_0 = vdotq_s32(vdupq_n_s32(0), v0_0ls, v1_0ls); - int32x4_t p_1 = vdotq_s32(vdupq_n_s32(0), v0_1ls, v1_1ls); - - p_0 = vdotq_s32(p_0, v0_0hs, v1_0hs); - p_1 = vdotq_s32(p_1, v0_1hs, v1_1hs); + const int32x4_t p_0 = vdotq_s32(vdotq_s32(vdupq_n_s32(0), v0_0ls, v1_0ls), v0_0hs, v1_0hs); + const int32x4_t p_1 = vdotq_s32(vdotq_s32(vdupq_n_s32(0), v0_1ls, v1_1ls), v0_1hs, v1_1hs); - sum0 += x0->d*y0->d*vaddvq_s32(p_0); - sum1 += x1->d*y1->d*vaddvq_s32(p_1); +#if 0 + // note: this is faster for 4-6 threads by slower for more threads + sumv0 = vmlaq_n_f32(sumv0, vcvtq_f32_s32(p_0), x0->d*y0->d); + sumv1 = vmlaq_n_f32(sumv1, vcvtq_f32_s32(p_1), x1->d*y1->d); +#else + sumv0 = vaddq_f32(sumv0, vmulq_f32(vcvtq_f32_s32(p_0), vdupq_n_f32(x0->d*y0->d))); + sumv1 = vaddq_f32(sumv1, vmulq_f32(vcvtq_f32_s32(p_1), vdupq_n_f32(x1->d*y1->d))); +#endif #else const int16x8_t pl0l = vmull_s8(vget_low_s8 (v0_0ls), vget_low_s8 (v1_0ls)); const int16x8_t pl0h = vmull_s8(vget_high_s8(v0_0ls), vget_high_s8(v1_0ls)); @@ -2826,21 +2829,17 @@ static void ggml_vec_dot_q4_0_q8_0(const int n, float * restrict s, const void * const int16x8_t ph1l = vmull_s8(vget_low_s8 (v0_1hs), vget_low_s8 (v1_1hs)); const int16x8_t ph1h = vmull_s8(vget_high_s8(v0_1hs), vget_high_s8(v1_1hs)); - const int16x8_t pl_0 = vaddq_s16(pl0l, pl0h); - const int16x8_t ph_0 = vaddq_s16(ph0l, ph0h); - - const int16x8_t pl_1 = vaddq_s16(pl1l, pl1h); - const int16x8_t ph_1 = vaddq_s16(ph1l, ph1h); + const int32x4_t pl0 = vaddq_s32(vpaddlq_s16(pl0l), vpaddlq_s16(pl0h)); + const int32x4_t ph0 = vaddq_s32(vpaddlq_s16(ph0l), vpaddlq_s16(ph0h)); + const int32x4_t pl1 = vaddq_s32(vpaddlq_s16(pl1l), vpaddlq_s16(pl1h)); + const int32x4_t ph1 = vaddq_s32(vpaddlq_s16(ph1l), vpaddlq_s16(ph1h)); - const int16x8_t p_0 = vaddq_s16(pl_0, ph_0); - const int16x8_t p_1 = vaddq_s16(pl_1, ph_1); - - sum0 += x0->d*y0->d*vaddvq_s16(p_0); - sum1 += x1->d*y1->d*vaddvq_s16(p_1); + sumv0 = vmlaq_n_f32(sumv0, vcvtq_f32_s32(vaddq_s32(pl0, ph0)), x0->d*y0->d); + sumv1 = vmlaq_n_f32(sumv1, vcvtq_f32_s32(vaddq_s32(pl1, ph1)), x1->d*y1->d); #endif } - sumf = sum0 + sum1; + sumf = vaddvq_f32(sumv0) + vaddvq_f32(sumv1); #elif defined(__AVX2__) // Initialize accumulator with zeros __m256 acc = _mm256_setzero_ps(); -- cgit v1.2.3