From 3eaacf235ec0875c838c54a5f498172c52bf56f1 Mon Sep 17 00:00:00 2001 From: Iwan Kawrakow Date: Thu, 21 Aug 2025 13:50:06 +0300 Subject: [PATCH] Use bperm trick for iq3_k -> 5% PP performance gain --- ggml/src/ggml-cuda/mmq.cuh | 42 +++++++++++++++++--------------------- 1 file changed, 19 insertions(+), 23 deletions(-) diff --git a/ggml/src/ggml-cuda/mmq.cuh b/ggml/src/ggml-cuda/mmq.cuh index 455e20ee..304942eb 100644 --- a/ggml/src/ggml-cuda/mmq.cuh +++ b/ggml/src/ggml-cuda/mmq.cuh @@ -2696,8 +2696,6 @@ template static __device__ __forceinlin constexpr int qstep = 8; const int kqsx = threadIdx.x % qstep; - uint32_t aux32[4]; - const uint8_t * aux8 = (const uint8_t *)aux32; #pragma unroll for (int i0 = 0; i0 < mmq_y; i0 += nwarps * WARP_SIZE/qstep) { int i = i0 + threadIdx.y*(WARP_SIZE/qstep) + threadIdx.x/qstep; @@ -2711,35 +2709,33 @@ template static __device__ __forceinlin const float d = bxi->d; uint16_t extra = bxi->extra >> (kqsx/4); + uint32_t extra32[2] = { uint32_t(extra & 0xff) * 0x01010101, uint32_t(extra >> 8) * 0x01010101 }; int qh = get_int_b2(bxi->qh, kqsx); #pragma unroll for (int l = 0; l < qstep/4; ++l) { + //extra << 3, extra << 1, extra >> 1, extra >> 3 const int ql = get_int_b2(bxi->qs, kqsx + qstep*l); - aux32[0] = ((ql >> 0) & 0x03030303) | ((qh << 2) & 0x04040404); - aux32[1] = ((ql >> 2) & 0x03030303) | ((qh << 1) & 0x04040404); - aux32[2] = ((ql >> 4) & 0x03030303) | ((qh >> 0) & 0x04040404); - aux32[3] = ((ql >> 6) & 0x03030303) | ((qh >> 1) & 0x04040404); + uint32_t val1 = ((ql >> 0) & 0x33333333) | ((extra32[l] << 3) & 0x88888888) + | ((qh << 2) & 0x04040404) | ((qh << 4) & 0x40404040); + uint32_t val2 = ((ql >> 2) & 0x33333333) | ((extra32[l] << 1) & 0x88888888) + | ((qh << 1) & 0x04040404) | ((qh << 3) & 0x40404040); + int2 v1 = get_int_from_table_16(val1, iq3nl_values); + int2 v2 = get_int_from_table_16(val2, iq3nl_values); - const int val0 = int_from_table_2(aux8+ 0, iq3k_table + ((extra << 6) & 0x40)); - const int val1 = int_from_table_2(aux8+ 4, iq3k_table + ((extra << 4) & 0x40)); - const int val2 = int_from_table_2(aux8+ 8, iq3k_table + ((extra << 2) & 0x40)); - const int val3 = int_from_table_2(aux8+12, iq3k_table + ((extra << 0) & 0x40)); - - extra >>= 8; - qh >>= 4; + qh >>= 4; #ifdef INT8_MMA_AVAILABLE - x_qs[i*MMQ_MMA_TILE_X_K_Q3_K + kqsx + 32*l + 0] = val0; - x_qs[i*MMQ_MMA_TILE_X_K_Q3_K + kqsx + 32*l + 8] = val1; - x_qs[i*MMQ_MMA_TILE_X_K_Q3_K + kqsx + 32*l + 16] = val2; - x_qs[i*MMQ_MMA_TILE_X_K_Q3_K + kqsx + 32*l + 24] = val3; + x_qs[i*MMQ_MMA_TILE_X_K_Q3_K + kqsx + 32*l + 0] = v1.x; + x_qs[i*MMQ_MMA_TILE_X_K_Q3_K + kqsx + 32*l + 8] = v2.x; + x_qs[i*MMQ_MMA_TILE_X_K_Q3_K + kqsx + 32*l + 16] = v1.y; + x_qs[i*MMQ_MMA_TILE_X_K_Q3_K + kqsx + 32*l + 24] = v2.y; #else - x_qs[i*(2*WARP_SIZE + 1) + kqsx + 32*l + 0] = val0; - x_qs[i*(2*WARP_SIZE + 1) + kqsx + 32*l + 8] = val1; - x_qs[i*(2*WARP_SIZE + 1) + kqsx + 32*l + 16] = val2; - x_qs[i*(2*WARP_SIZE + 1) + kqsx + 32*l + 24] = val3; + x_qs[i*(2*WARP_SIZE + 1) + kqsx + 32*l + 0] = v1.x; + x_qs[i*(2*WARP_SIZE + 1) + kqsx + 32*l + 8] = v2.x; + x_qs[i*(2*WARP_SIZE + 1) + kqsx + 32*l + 16] = v1.y; + x_qs[i*(2*WARP_SIZE + 1) + kqsx + 32*l + 24] = v2.y; #endif // INT8_MMA_AVAILABLE } @@ -2781,10 +2777,10 @@ template static __device__ __forceinlin const float d = __half2float(dptr[0]); const block_iq3_ks * bxi = (const block_iq3_ks *)(dptr + 1) + kbx0; - uint16_t extra = bxi->extra >> 8; + //uint16_t extra = bxi->extra >> 8; int qh = get_int_b2(bxi->qh, kqsx); - uint32_t extra32 = extra * 0x01010101; + uint32_t extra32 = uint32_t(bxi->extra >> 8) * 0x01010101; #pragma unroll for (int l = 0; l < qstep/4; ++l) {