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| author | Mitja Felicijan <mitja.felicijan@gmail.com> | 2026-02-12 20:57:17 +0100 |
|---|---|---|
| committer | Mitja Felicijan <mitja.felicijan@gmail.com> | 2026-02-12 20:57:17 +0100 |
| commit | b333b06772c89d96aacb5490d6a219fba7c09cc6 (patch) | |
| tree | 211df60083a5946baa2ed61d33d8121b7e251b06 /llama.cpp/ggml/src/ggml-opencl/kernels/flash_attn_f32.cl | |
| download | llmnpc-b333b06772c89d96aacb5490d6a219fba7c09cc6.tar.gz | |
Engage!
Diffstat (limited to 'llama.cpp/ggml/src/ggml-opencl/kernels/flash_attn_f32.cl')
| -rw-r--r-- | llama.cpp/ggml/src/ggml-opencl/kernels/flash_attn_f32.cl | 371 |
1 files changed, 371 insertions, 0 deletions
diff --git a/llama.cpp/ggml/src/ggml-opencl/kernels/flash_attn_f32.cl b/llama.cpp/ggml/src/ggml-opencl/kernels/flash_attn_f32.cl new file mode 100644 index 0000000..a6d7479 --- /dev/null +++ b/llama.cpp/ggml/src/ggml-opencl/kernels/flash_attn_f32.cl @@ -0,0 +1,371 @@ +#pragma OPENCL EXTENSION cl_khr_fp16 : enable + +#define ACC_TYPE float +#define ACC_TYPE4 float4 +#define DATA_TYPE float +#define DATA_TYPE4 float4 +#define MASK_DATA_TYPE half +#define CONVERT_ACC4(x) (x) +#define CONVERT_DATA4(x) (x) + +#define DK_VEC (DK/4) +#define DV_VEC (DV/4) +#define WG_SIZE (BLOCK_M) +#define Q1_WG_SIZE 64 + +inline float get_alibi_slope( + const float max_bias, const uint h, const uint n_head_log2, const float m0, const float m1 +) { + if (max_bias <= 0.0f) { + return 1.0f; + } + const float base = h < n_head_log2 ? m0 : m1; + const int exph = h < n_head_log2 ? h + 1 : 2*(h - n_head_log2) + 1; + + return pow(base, exph); +} +__kernel void flash_attn_f32( + const global void * q_void, ulong q_offset, + const global void * k_void, ulong k_offset, + const global void * v_void, ulong v_offset, + global void * o_void, ulong o_offset, + const float scale, + const int n_q, + const int n_kv, + const int is_causal, + const int n_head, + const ulong q_nb1, const ulong q_nb2, const ulong q_nb3, + const ulong k_nb1, const ulong k_nb2, const ulong k_nb3, + const ulong v_nb1, const ulong v_nb2, const ulong v_nb3, + const ulong o_nb1, const ulong o_nb2, const ulong o_nb3, + const float max_bias, + const float m0, + const float m1, + const int n_head_log2, + const float logit_softcap, + const int n_head_kv, + const global void* mask_void, + const ulong mask_offset, + const ulong mask_nb1, + const ulong mask_nb2, + const ulong mask_nb3, + const int mask_ne2, + const int mask_ne3, + const global void* sinks_void, + const ulong sinks_offset +) { + const int tid = get_local_id(0); + const int block_q_idx = get_group_id(0); + const int head_batch_idx = get_global_id(1); + + const int my_query_row = block_q_idx * BLOCK_M + tid; + + const int batch_idx = head_batch_idx / n_head; + const int head_idx = head_batch_idx % n_head; + + const int gqa_ratio = n_head / n_head_kv; + const int head_kv_idx = head_idx / gqa_ratio; + + const global char* q_base = (const global char*)q_void + q_offset; + const global char* k_base = (const global char*)k_void + k_offset; + const global char* v_base = (const global char*)v_void + v_offset; + global char* o_base = (global char*)o_void + o_offset; + + const global char* mask_base = NULL; + if (mask_void != NULL) { + const int mask_head_idx = head_idx % mask_ne2; + const int mask_batch_idx = batch_idx % mask_ne3; + mask_base = (const global char*)mask_void + mask_offset + mask_batch_idx * mask_nb3 + mask_head_idx * mask_nb2; + } + + ACC_TYPE4 q_priv[DK_VEC]; + if (my_query_row < n_q) { + const ulong q_row_offset = batch_idx * q_nb3 + head_idx * q_nb2 + my_query_row * q_nb1; + const global DATA_TYPE4* q_ptr = (const global DATA_TYPE4*)(q_base + q_row_offset); + #pragma unroll + for (int i = 0; i < DK_VEC; ++i) { + q_priv[i] = CONVERT_ACC4(q_ptr[i]); + } + } + + ACC_TYPE4 o_acc[DV_VEC]; + #pragma unroll + for (int i = 0; i < DV_VEC; ++i) { + o_acc[i] = (ACC_TYPE4)(0.0f); + } + ACC_TYPE m_i = -INFINITY; + ACC_TYPE l_i = 0.0f; + + float slope = get_alibi_slope(max_bias, head_idx, n_head_log2, m0, m1); + + __local DATA_TYPE4 l_k[BLOCK_N][DK_VEC]; + __local DATA_TYPE4 l_v[BLOCK_N][DV_VEC]; + + for (int k_start = 0; k_start < n_kv; k_start += BLOCK_N) { + for (int i = tid; i < BLOCK_N * DK_VEC; i += WG_SIZE) { + const int row = i / DK_VEC; + const int col = i % DK_VEC; + const int k_row_idx = k_start + row; + if (k_row_idx < n_kv) { + const ulong k_row_offset = batch_idx * k_nb3 + head_kv_idx * k_nb2 + k_row_idx * k_nb1; + l_k[row][col] = ((__global DATA_TYPE4*)(k_base + k_row_offset))[col]; + } + } + for (int i = tid; i < BLOCK_N * DV_VEC; i += WG_SIZE) { + const int row = i / DV_VEC; + const int col = i % DV_VEC; + const int v_row_idx = k_start + row; + if (v_row_idx < n_kv) { + const ulong v_row_offset = batch_idx * v_nb3 + head_kv_idx * v_nb2 + v_row_idx * v_nb1; + l_v[row][col] = ((__global DATA_TYPE4*)(v_base + v_row_offset))[col]; + } + } + barrier(CLK_LOCAL_MEM_FENCE); + + if (my_query_row >= n_q) { + continue; + } + + for (int j = 0; j < BLOCK_N; j += 2) { + const int k_row0 = k_start + j; + const int k_row1 = k_start + j + 1; + + ACC_TYPE4 dot_acc0 = (ACC_TYPE4)(0.0f); + ACC_TYPE4 dot_acc1 = (ACC_TYPE4)(0.0f); + #pragma unroll + for (int k = 0; k < DK_VEC; k++) { + dot_acc0 = mad(q_priv[k], CONVERT_ACC4(l_k[j][k]), dot_acc0); + dot_acc1 = mad(q_priv[k], CONVERT_ACC4(l_k[j+1][k]), dot_acc1); + } + ACC_TYPE score0 = (dot_acc0.s0 + dot_acc0.s1 + dot_acc0.s2 + dot_acc0.s3) * scale; + ACC_TYPE score1 = (dot_acc1.s0 + dot_acc1.s1 + dot_acc1.s2 + dot_acc1.s3) * scale; + + if (is_causal) { + if (k_row0 > (n_kv - n_q + my_query_row)) score0 = -INFINITY; + if (k_row1 > (n_kv - n_q + my_query_row)) score1 = -INFINITY; + } + + if (k_row0 >= n_kv) score0 = -INFINITY; + if (k_row1 >= n_kv) score1 = -INFINITY; + + if (mask_base != NULL) { + const global MASK_DATA_TYPE* mask_ptr = (const global MASK_DATA_TYPE*)(mask_base + my_query_row * mask_nb1); + if (k_row0 < n_kv) score0 += slope * (ACC_TYPE)mask_ptr[k_row0]; + if (k_row1 < n_kv) score1 += slope * (ACC_TYPE)mask_ptr[k_row1]; + } + + if (logit_softcap > 0.0f) { + score0 = logit_softcap * tanh(score0 / logit_softcap); + score1 = logit_softcap * tanh(score1 / logit_softcap); + } + + const ACC_TYPE m_new = max(m_i, max(score0, score1)); + const ACC_TYPE p0 = exp(score0 - m_new); + const ACC_TYPE p1 = exp(score1 - m_new); + const ACC_TYPE scale_prev = exp(m_i - m_new); + + #pragma unroll + for (int i = 0; i < DV_VEC; ++i) { + o_acc[i] = o_acc[i] * scale_prev + p0 * CONVERT_ACC4(l_v[j][i]) + p1 * CONVERT_ACC4(l_v[j+1][i]); + } + l_i = l_i * scale_prev + p0 + p1; + m_i = m_new; + } + } + + if (my_query_row < n_q) { + if (sinks_void != NULL) { + const global ACC_TYPE* sinks_ptr = (const global ACC_TYPE*)((const global char*)sinks_void + sinks_offset); + const ACC_TYPE m_sink = sinks_ptr[head_idx]; + const ACC_TYPE m_final = max(m_i, m_sink); + + const ACC_TYPE scale_o = exp(m_i - m_final); + #pragma unroll + for (int i = 0; i < DV_VEC; ++i) { + o_acc[i] *= scale_o; + } + + l_i = l_i * exp(m_i - m_final) + exp(m_sink - m_final); + } + + const ulong o_row_offset = batch_idx * o_nb3 + my_query_row * o_nb2 + head_idx * o_nb1; + global DATA_TYPE4 *o_row = (global DATA_TYPE4 *)(o_base + o_row_offset); + if (l_i > 0.0f) { + const ACC_TYPE l_inv = 1.0f / l_i; + #pragma unroll + for (int i = 0; i < DV_VEC; ++i) { + o_row[i] = CONVERT_DATA4(o_acc[i] * l_inv); + } + } else { + #pragma unroll + for (int i = 0; i < DV_VEC; ++i) { + o_row[i] = (DATA_TYPE4)(0.0f); + } + } + } +} + +__kernel void flash_attn_f32_q1( + const global void * q_void, ulong q_offset, + const global void * k_void, ulong k_offset, + const global void * v_void, ulong v_offset, + global void * o_void, ulong o_offset, + const float scale, + const int n_q, + const int n_kv, + const int is_causal, + const int n_head, + const ulong q_nb1, const ulong q_nb2, const ulong q_nb3, + const ulong k_nb1, const ulong k_nb2, const ulong k_nb3, + const ulong v_nb1, const ulong v_nb2, const ulong v_nb3, + const ulong o_nb1, const ulong o_nb2, const ulong o_nb3, + const float max_bias, + const float m0, + const float m1, + const int n_head_log2, + const float logit_softcap, + const int n_head_kv, + const global void* mask_void, + const ulong mask_offset, + const ulong mask_nb1, + const ulong mask_nb2, + const ulong mask_nb3, + const int mask_ne2, + const int mask_ne3, + const global void* sinks_void, + const ulong sinks_offset +) { + const int tid = get_local_id(0); + const int head_batch_idx = get_global_id(1); + + const int batch_idx = head_batch_idx / n_head; + const int head_idx = head_batch_idx % n_head; + + const int gqa_ratio = n_head / n_head_kv; + const int head_kv_idx = head_idx / gqa_ratio; + + const global char* q_base = (const global char*)q_void + q_offset; + const global char* k_base = (const global char*)k_void + k_offset; + const global char* v_base = (const global char*)v_void + v_offset; + global char* o_base = (global char*)o_void + o_offset; + + const global char* mask_base = NULL; + if (mask_void != NULL) { + const int mask_head_idx = head_idx % mask_ne2; + const int mask_batch_idx = batch_idx % mask_ne3; + mask_base = (const global char*)mask_void + mask_offset + mask_batch_idx * mask_nb3 + mask_head_idx * mask_nb2; + } + + ACC_TYPE4 q_priv[DK_VEC]; + const ulong q_row_offset = batch_idx * q_nb3 + head_idx * q_nb2; + const global DATA_TYPE4* q_ptr = (const global DATA_TYPE4*)(q_base + q_row_offset); + #pragma unroll + for (int i = 0; i < DK_VEC; ++i) { + q_priv[i] = CONVERT_ACC4(q_ptr[i]); + } + + float slope = get_alibi_slope(max_bias, head_idx, n_head_log2, m0, m1); + + const global ACC_TYPE* sinks_ptr = NULL; + if (sinks_void != NULL) { + sinks_ptr = (const global ACC_TYPE*)((const global char*)sinks_void + sinks_offset); + } + + ACC_TYPE m_i = (sinks_ptr != NULL) ? sinks_ptr[head_idx] : -INFINITY; + for (int k_idx = tid; k_idx < n_kv; k_idx += Q1_WG_SIZE) { + const ulong k_row_offset = batch_idx * k_nb3 + head_kv_idx * k_nb2 + k_idx * k_nb1; + const global DATA_TYPE4* k_ptr = (const global DATA_TYPE4*)(k_base + k_row_offset); + ACC_TYPE4 dot_acc = (ACC_TYPE4)(0.0f); + #pragma unroll + for (int k = 0; k < DK_VEC; k++) { + dot_acc = mad(q_priv[k], CONVERT_ACC4(k_ptr[k]), dot_acc); + } + ACC_TYPE score = (dot_acc.s0 + dot_acc.s1 + dot_acc.s2 + dot_acc.s3) * scale; + if (mask_base != NULL) { + const global MASK_DATA_TYPE* mask_ptr = (const global MASK_DATA_TYPE*)(mask_base); + score += slope * (ACC_TYPE)mask_ptr[k_idx]; + } + if (logit_softcap > 0.0f) { + score = logit_softcap * tanh(score / logit_softcap); + } + m_i = max(m_i, score); + } + + __local ACC_TYPE local_m[Q1_WG_SIZE]; + local_m[tid] = m_i; + barrier(CLK_LOCAL_MEM_FENCE); + #pragma unroll + for (int s = Q1_WG_SIZE / 2; s > 0; s >>= 1) { + if (tid < s) local_m[tid] = max(local_m[tid], local_m[tid + s]); + barrier(CLK_LOCAL_MEM_FENCE); + } + const ACC_TYPE m_final = local_m[0]; + + ACC_TYPE4 o_acc[DV_VEC]; + #pragma unroll + for (int i = 0; i < DV_VEC; ++i) o_acc[i] = (ACC_TYPE4)(0.0f); + ACC_TYPE l_i = 0.0f; + + for (int k_idx = tid; k_idx < n_kv; k_idx += Q1_WG_SIZE) { + const ulong k_row_offset = batch_idx * k_nb3 + head_kv_idx * k_nb2 + k_idx * k_nb1; + const ulong v_row_offset = batch_idx * v_nb3 + head_kv_idx * v_nb2 + k_idx * v_nb1; + const global DATA_TYPE4* k_ptr = (const global DATA_TYPE4*)(k_base + k_row_offset); + const global DATA_TYPE4* v_ptr = (const global DATA_TYPE4*)(v_base + v_row_offset); + ACC_TYPE4 dot_acc = (ACC_TYPE4)(0.0f); + #pragma unroll + for (int k = 0; k < DK_VEC; k++) { + dot_acc = mad(q_priv[k], CONVERT_ACC4(k_ptr[k]), dot_acc); + } + ACC_TYPE score = (dot_acc.s0 + dot_acc.s1 + dot_acc.s2 + dot_acc.s3) * scale; + if (mask_base != NULL) { + const global MASK_DATA_TYPE* mask_ptr = (const global MASK_DATA_TYPE*)(mask_base); + score += slope * (ACC_TYPE)mask_ptr[k_idx]; + } + if (logit_softcap > 0.0f) { + score = logit_softcap * tanh(score / logit_softcap); + } + const ACC_TYPE p = exp(score - m_final); + l_i += p; + #pragma unroll + for (int i = 0; i < DV_VEC; i++) { + o_acc[i] = mad(p, CONVERT_ACC4(v_ptr[i]), o_acc[i]); + } + } + + __local ACC_TYPE local_l[Q1_WG_SIZE]; + __local ACC_TYPE4 local_o_comp[Q1_WG_SIZE]; + local_l[tid] = l_i; + barrier(CLK_LOCAL_MEM_FENCE); + #pragma unroll + for (int s = Q1_WG_SIZE / 2; s > 0; s >>= 1) { + if (tid < s) local_l[tid] += local_l[tid + s]; + barrier(CLK_LOCAL_MEM_FENCE); + } + + const ulong o_row_offset = batch_idx * o_nb3 + head_idx * o_nb1; + global DATA_TYPE4 *o_row = (global DATA_TYPE4 *)(o_base + o_row_offset); + ACC_TYPE l_final = local_l[0]; + + if (sinks_ptr != NULL) { + l_final += exp(sinks_ptr[head_idx] - m_final); + } + + if (l_final > 0.0f) { + const ACC_TYPE l_inv = 1.0f / l_final; + for (int i = 0; i < DV_VEC; i++) { + local_o_comp[tid] = o_acc[i]; + barrier(CLK_LOCAL_MEM_FENCE); + #pragma unroll + for (int s = Q1_WG_SIZE / 2; s > 0; s >>= 1) { + if (tid < s) local_o_comp[tid] += local_o_comp[tid + s]; + barrier(CLK_LOCAL_MEM_FENCE); + } + if (tid == 0) { + o_row[i] = CONVERT_DATA4(local_o_comp[0] * l_inv); + } + } + } else if (tid == 0) { + #pragma unroll + for (int i = 0; i < DV_VEC; ++i) o_row[i] = (DATA_TYPE4)(0.0f); + } +} |
