From 1d91c16869a7040c2c500e70fb7eb53534048e2c Mon Sep 17 00:00:00 2001 From: Iwan Kawrakow Date: Thu, 21 Aug 2025 17:35:33 +0300 Subject: [PATCH] Use bperm trick for iq2_k gemm -> ~5% gain --- ggml/src/ggml-cuda/mmq.cuh | 35 ++++++++++++++++++++++++++++++----- 1 file changed, 30 insertions(+), 5 deletions(-) diff --git a/ggml/src/ggml-cuda/mmq.cuh b/ggml/src/ggml-cuda/mmq.cuh index bc5ea269..613463dc 100644 --- a/ggml/src/ggml-cuda/mmq.cuh +++ b/ggml/src/ggml-cuda/mmq.cuh @@ -2679,7 +2679,7 @@ template static __device__ __forceinlin constexpr int qstep = 8; const int kqsx = threadIdx.x % qstep; -#pragma unroll + #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; @@ -2689,13 +2689,37 @@ template static __device__ __forceinlin const block_iq2_k * bxi = (const block_iq2_k *)(x + i*stride) + kbx0; - auto all_values = (const int *)iq2k_table; - const float d = bxi->d; - uint16_t extra = bxi->extra >> (kqsx/4); - #pragma unroll +#ifdef __CUDA_ARCH__ + + uint32_t extra32[2] = { uint32_t(extra & 0xff) * 0x01010101, uint32_t(extra >> 8) * 0x01010101 }; + #pragma unroll + for (int l = 0; l < qstep/4; ++l) { + const int ql = get_int_b4(bxi->qs, kqsx + qstep*l); + uint32_t val1 = ((ql >> 0) & 0x33333333) | ((extra32[l] << 2) & 0x44444444); + uint32_t val2 = ((ql >> 2) & 0x33333333) | ((extra32[l] << 0) & 0x44444444); + int2 v1 = get_int_from_table_8(val1, iq2nl_values); + int2 v2 = get_int_from_table_8(val2, iq2nl_values); +#ifdef INT8_MMA_AVAILABLE + 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] = 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 + } + +#else + + auto all_values = (const int *)iq2k_table; + + #pragma unroll for (int l = 0; l < qstep/4; ++l) { const int ql = get_int_b4(bxi->qs, kqsx + qstep*l); @@ -2714,6 +2738,7 @@ template static __device__ __forceinlin extra >>= 8; } +#endif // __CUDA_ARCH__ #ifdef INT8_MMA_AVAILABLE x_df[i*MMQ_MMA_TILE_X_K_Q3_K + 2*kqsx+0] = d * (((bxi->scales[kqsx] >> 0) & 0xf) - 8);