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-rw-r--r--llama.cpp/ggml/src/ggml-sycl/norm.cpp654
1 files changed, 654 insertions, 0 deletions
diff --git a/llama.cpp/ggml/src/ggml-sycl/norm.cpp b/llama.cpp/ggml/src/ggml-sycl/norm.cpp
new file mode 100644
index 0000000..00702b5
--- /dev/null
+++ b/llama.cpp/ggml/src/ggml-sycl/norm.cpp
@@ -0,0 +1,654 @@
+#include "norm.hpp"
+#include "ggml-sycl/common.hpp"
+#include "ggml-sycl/presets.hpp"
+
+static void norm_f32(const float* x, float* dst, const int ncols, const int64_t stride_row, const int64_t stride_channel,
+ const int64_t stride_sample, const float eps, const sycl::nd_item<3>& item_ct1, sycl::float2* s_sum, int block_size) {
+
+ const int nrows = item_ct1.get_group_range(2);
+ const int nchannels = item_ct1.get_group_range(1);
+
+ const int nthreads = item_ct1.get_local_range(2);
+ const int sample = item_ct1.get_group(0);
+ const int channel = item_ct1.get_group(1);
+ const int row = item_ct1.get_group(2);
+
+ const int tid = item_ct1.get_local_id(2);
+ const int nwarps = nthreads / WARP_SIZE;
+
+ const auto strided_offset = calculate_offset<3>({stride_sample, stride_channel, stride_row}, {sample, channel, row});
+ const auto packed_offset = calculate_offset<3>({nchannels * nrows * ncols, nrows * ncols, ncols}, {sample, channel, row});
+
+ x += strided_offset;
+ dst += packed_offset;
+
+ sycl::float2 mean_var = sycl::float2(0.f, 0.f);
+
+ for (int col = tid; col < ncols; col += block_size) {
+ const float xi = x[col];
+ mean_var.x() += xi;
+ mean_var.y() += xi * xi;
+ }
+
+ // sum up partial sums
+ mean_var = warp_reduce_sum(mean_var, item_ct1);
+ if (block_size > WARP_SIZE) {
+ const auto sub_group = item_ct1.get_sub_group();
+ const auto sg_id = sub_group.get_group_linear_id();
+ const auto wi_in_sg = sub_group.get_local_linear_id();
+ if (wi_in_sg == 0) {
+ s_sum[sg_id] = mean_var;
+ }
+ item_ct1.barrier(sycl::access::fence_space::local_space);
+ mean_var = 0.f;
+ const size_t nreduce = ceil_div(nwarps, WARP_SIZE);
+ for (size_t i = 0; i < nreduce; i += 1)
+ {
+ mean_var += s_sum[wi_in_sg + i * WARP_SIZE];
+ }
+ mean_var = warp_reduce_sum(mean_var, item_ct1);
+ }
+
+ const float mean = mean_var.x() / ncols;
+ const float var = mean_var.y() / ncols - mean * mean;
+ const float inv_std = sycl::rsqrt(var + eps);
+
+ for (int col = tid; col < ncols; col += block_size) {
+ dst[col] = (x[col] - mean) * inv_std;
+ }
+}
+
+static void group_norm_f32(const float* x, float* dst, const int group_size, const int ne_elements, const float eps,
+ const sycl::nd_item<3>& item_ct1, float* s_sum, int block_size) {
+ int start = item_ct1.get_group(2) * group_size;
+ int end = start + group_size;
+ const int nthreads = item_ct1.get_local_range(2);
+ const int nwarps = nthreads / WARP_SIZE;
+ start += item_ct1.get_local_id(2);
+ size_t nreduce = nwarps / WARP_SIZE;
+
+ if (end >= ne_elements) {
+ end = ne_elements;
+ }
+
+ float tmp = 0.0f; // partial sum for thread in warp
+
+ for (int j = start; j < end; j += block_size) {
+ tmp += x[j];
+ }
+
+ tmp = warp_reduce_sum(tmp, item_ct1);
+ if (block_size > WARP_SIZE) {
+
+ int warp_id = item_ct1.get_local_id(2) / WARP_SIZE;
+ int lane_id = item_ct1.get_local_id(2) % WARP_SIZE;
+ if (lane_id == 0) {
+ s_sum[warp_id] = tmp;
+ }
+ /*
+ DPCT1118:1: SYCL group functions and algorithms must be encountered in
+ converged control flow. You may need to adjust the code.
+ */
+ /*
+ DPCT1065:54: Consider replacing sycl::nd_item::barrier() with
+ sycl::nd_item::barrier(sycl::access::fence_space::local_space) for
+ better performance if there is no access to global memory.
+ */
+ item_ct1.barrier();
+ tmp = 0.f;
+ for (size_t i = 0; i < nreduce; i += 1)
+ {
+ tmp += s_sum[lane_id + i * WARP_SIZE];
+ }
+ tmp = warp_reduce_sum(tmp, item_ct1);
+ }
+
+ float mean = tmp / group_size;
+ tmp = 0.0f;
+
+ for (int j = start; j < end; j += block_size) {
+ float xi = x[j] - mean;
+ dst[j] = xi;
+ tmp += xi * xi;
+ }
+
+ tmp = warp_reduce_sum(tmp, item_ct1);
+ if (block_size > WARP_SIZE) {
+
+ int warp_id = item_ct1.get_local_id(2) / WARP_SIZE;
+ int lane_id = item_ct1.get_local_id(2) % WARP_SIZE;
+ if (lane_id == 0) {
+ s_sum[warp_id] = tmp;
+ }
+ /*
+ DPCT1118:2: SYCL group functions and algorithms must be encountered in
+ converged control flow. You may need to adjust the code.
+ */
+ /*
+ DPCT1065:55: Consider replacing sycl::nd_item::barrier() with
+ sycl::nd_item::barrier(sycl::access::fence_space::local_space) for
+ better performance if there is no access to global memory.
+ */
+ item_ct1.barrier();
+ tmp = 0.f;
+ for (size_t i = 0; i < nreduce; i += 1)
+ {
+ tmp += s_sum[lane_id + i * WARP_SIZE];
+ }
+ tmp = warp_reduce_sum(tmp, item_ct1);
+ }
+
+ float variance = tmp / group_size;
+ float scale = sycl::rsqrt(variance + eps);
+ for (int j = start; j < end; j += block_size) {
+ dst[j] *= scale;
+ }
+}
+
+static void rms_norm_f32(const float* x, float* dst, const int ncols, const int64_t stride_row, const int64_t stride_channel,
+ const int64_t stride_sample, const float eps, const sycl::nd_item<3>& item_ct1, float* s_sum, int block_size) {
+
+ const int nrows = item_ct1.get_group_range(2);
+ const int nchannels = item_ct1.get_group_range(1);
+
+ const int sample = item_ct1.get_group(0);
+ const int channel = item_ct1.get_group(1);
+ const int row = item_ct1.get_group(2);
+
+ const int nthreads = item_ct1.get_local_range(2);
+
+ const int tid = item_ct1.get_local_id(2);
+ const int nwarps = nthreads / WARP_SIZE;
+
+ const auto strided_offset = calculate_offset<3>({stride_sample, stride_channel, stride_row}, {sample, channel, row});
+ const auto packed_offset = calculate_offset<3>({nchannels * nrows * ncols, nrows * ncols, ncols}, {sample, channel, row});
+
+ x += strided_offset;
+ dst += packed_offset;
+
+
+ float tmp = 0.0f; // partial sum for thread in warp
+
+ for (int col = tid; col < ncols; col += block_size) {
+ const float xi = x[col];
+ tmp += xi * xi;
+ }
+
+ // sum up partial sums
+ tmp = warp_reduce_sum(tmp, item_ct1);
+ if (block_size > WARP_SIZE) {
+ const auto sub_group = item_ct1.get_sub_group();
+ const auto sg_id = sub_group.get_group_linear_id();
+ const auto wi_in_sg = sub_group.get_local_linear_id();
+ if (wi_in_sg == 0) {
+ s_sum[sg_id] = tmp;
+ }
+
+ item_ct1.barrier(sycl::access::fence_space::local_space);
+ const size_t nreduce = ceil_div(nwarps, WARP_SIZE);
+ tmp = 0.f;
+ for (size_t i = 0; i < nreduce; i += 1)
+ {
+ tmp += s_sum[wi_in_sg + i * WARP_SIZE];
+ }
+ tmp = warp_reduce_sum(tmp, item_ct1);
+ }
+
+ const float mean = tmp / ncols;
+ const float scale = sycl::rsqrt(mean + eps);
+
+ for (int col = tid; col < ncols; col += block_size) {
+ dst[col] = scale * x[col];
+ }
+}
+
+static void l2_norm_f32(const float* x, float* dst, const int ncols, const float eps,
+ const sycl::nd_item<3>& item_ct1, float* s_sum, int block_size) {
+ const int row = item_ct1.get_group(2) * item_ct1.get_local_range(1) +
+ item_ct1.get_local_id(1);
+ const int tid = item_ct1.get_local_id(2);
+ const int nthreads = item_ct1.get_local_range(2);
+ const int nwarps = nthreads / WARP_SIZE;
+ float tmp = 0.0f; // partial sum for thread in warp
+
+ for (int col = tid; col < ncols; col += block_size) {
+ const float xi = x[row * ncols + col];
+ tmp += xi * xi;
+ }
+
+ // sum up partial sums
+ tmp = warp_reduce_sum(tmp, item_ct1);
+ if (block_size > WARP_SIZE) {
+
+ int warp_id = item_ct1.get_local_id(2) / WARP_SIZE;
+ int lane_id = item_ct1.get_local_id(2) % WARP_SIZE;
+ if (lane_id == 0) {
+ s_sum[warp_id] = tmp;
+ }
+ /*
+ DPCT1118:3: SYCL group functions and algorithms must be encountered in
+ converged control flow. You may need to adjust the code.
+ */
+ item_ct1.barrier(sycl::access::fence_space::local_space);
+ size_t nreduce = nwarps / WARP_SIZE;
+ tmp = 0.f;
+ for (size_t i = 0; i < nreduce; i += 1)
+ {
+ tmp += s_sum[lane_id + i * WARP_SIZE];
+ }
+ tmp = warp_reduce_sum(tmp, item_ct1);
+ }
+
+ const float scale = sycl::rsqrt(sycl::max(tmp, eps * eps));
+
+ for (int col = tid; col < ncols; col += block_size) {
+ dst[row * ncols + col] = scale * x[row * ncols + col];
+ }
+}
+
+static void norm_f32_sycl(const float * x, float * dst, const int ncols, const int nrows, const int nchannels, const int nsamples,
+ const int64_t stride_row, const int64_t stride_channel, const int64_t stride_sample,
+ const float eps, queue_ptr stream, int device) {
+
+ const sycl::range<3> global_dims(nsamples, nchannels, nrows);
+ if (ncols < 1024) {
+ const sycl::range<3> block_dims(1, 1, WARP_SIZE);
+ stream->submit([&](sycl::handler& cgh) {
+ cgh.parallel_for(
+ sycl::nd_range<3>(global_dims * block_dims, block_dims),
+ [=](sycl::nd_item<3> item_ct1)
+ [[sycl::reqd_sub_group_size(WARP_SIZE)]] {
+ norm_f32(x, dst, ncols, stride_row, stride_channel, stride_sample, eps, item_ct1, nullptr, WARP_SIZE);
+ });
+ });
+ }
+ else {
+ const int work_group_size = ggml_sycl_info().max_work_group_sizes[device];
+ assert(work_group_size % (WARP_SIZE * WARP_SIZE) == 0);
+ const sycl::range<3> block_dims(1, 1, work_group_size);
+ /*
+ DPCT1049:17: The work-group size passed to the SYCL kernel may exceed
+ the limit. To get the device limit, query
+ info::device::max_work_group_size. Adjust the work-group size if needed.
+ */
+ stream->submit([&](sycl::handler& cgh) {
+ sycl::local_accessor<sycl::float2, 1> s_sum_acc_ct1(
+ sycl::range<1>(work_group_size / WARP_SIZE), cgh);
+ cgh.parallel_for(
+ sycl::nd_range<3>(global_dims * block_dims, block_dims),
+ [=](sycl::nd_item<3> item_ct1)
+ [[sycl::reqd_sub_group_size(WARP_SIZE)]] {
+ norm_f32(x, dst, ncols, stride_row, stride_channel, stride_sample, eps, item_ct1, get_pointer(s_sum_acc_ct1), work_group_size);
+ });
+ });
+ }
+}
+
+static void group_norm_f32_sycl(const float* x, float* dst,
+ const int num_groups, const float eps, const int group_size,
+ const int ne_elements, queue_ptr stream, int device) {
+ if (group_size < 1024) {
+ const sycl::range<3> block_dims(1, 1, WARP_SIZE);
+ stream->submit([&](sycl::handler& cgh) {
+ const float eps_ct4 = eps;
+ cgh.parallel_for(
+ sycl::nd_range<3>(sycl::range<3>(1, 1, num_groups) * block_dims,
+ block_dims),
+ [=](sycl::nd_item<3> item_ct1)
+ [[sycl::reqd_sub_group_size(WARP_SIZE)]] {
+ group_norm_f32(
+ x, dst, group_size, ne_elements, eps_ct4, item_ct1,
+ nullptr, WARP_SIZE);
+ });
+ });
+ }
+ else {
+ const int work_group_size = ggml_sycl_info().max_work_group_sizes[device];
+ assert(work_group_size % (WARP_SIZE * WARP_SIZE) == 0);
+ const sycl::range<3> block_dims(1, 1, work_group_size);
+ /*
+ DPCT1049:18: The work-group size passed to the SYCL kernel may exceed
+ the limit. To get the device limit, query
+ info::device::max_work_group_size. Adjust the work-group size if needed.
+ */
+
+ stream->submit([&](sycl::handler& cgh) {
+ sycl::local_accessor<float, 1> s_sum_acc_ct1(sycl::range<1>(work_group_size / WARP_SIZE),
+ cgh);
+
+ const float eps_ct4 = eps;
+
+ cgh.parallel_for(
+ sycl::nd_range<3>(sycl::range<3>(1, 1, num_groups) * block_dims,
+ block_dims),
+ [=](sycl::nd_item<3> item_ct1)
+ [[sycl::reqd_sub_group_size(WARP_SIZE)]] {
+ group_norm_f32(x, dst, group_size, ne_elements,
+ eps_ct4, item_ct1,
+ get_pointer(s_sum_acc_ct1), work_group_size);
+ });
+ });
+ }
+}
+
+static void rms_norm_f32_sycl(const float* x, float* dst, const int ncols, const int nrows, const int nchannels, const int nsamples,
+ const int64_t stride_row, const int64_t stride_channel, const int64_t stride_sample, const float eps, queue_ptr stream, int device) {
+ // printf("%s ncols=%d, nrows=%d, WARP_SIZE=%d\n", __func__, ncols, nrows, WARP_SIZE);
+
+ const sycl::range<3> global_dims(nsamples, nchannels, nrows);
+ if (ncols < 1024) {
+ const sycl::range<3> block_dims(1, 1, WARP_SIZE);
+ stream->submit([&](sycl::handler& cgh) {
+ cgh.parallel_for(
+ sycl::nd_range<3>(global_dims * block_dims, block_dims),
+ [=](sycl::nd_item<3> item_ct1)
+ [[sycl::reqd_sub_group_size(WARP_SIZE)]] {
+ rms_norm_f32(x, dst, ncols, stride_row, stride_channel, stride_sample, eps, item_ct1, nullptr, WARP_SIZE);
+ });
+ });
+ }
+ else {
+ const int work_group_size = ggml_sycl_info().max_work_group_sizes[device];
+ assert(work_group_size % (WARP_SIZE * WARP_SIZE) == 0);
+ const sycl::range<3> block_dims(1, 1, work_group_size);
+ /*
+ DPCT1049:19: The work-group size passed to the SYCL kernel may exceed
+ the limit. To get the device limit, query
+ info::device::max_work_group_size. Adjust the work-group size if needed.
+ */
+ stream->submit([&](sycl::handler& cgh) {
+ sycl::local_accessor<float, 1> s_sum_acc_ct1(sycl::range<1>(work_group_size / WARP_SIZE),
+ cgh);
+ cgh.parallel_for(
+ sycl::nd_range<3>(global_dims * block_dims, block_dims),
+ [=](sycl::nd_item<3> item_ct1)
+ [[sycl::reqd_sub_group_size(WARP_SIZE)]] {
+ rms_norm_f32(x, dst, ncols, stride_row, stride_channel, stride_sample, eps, item_ct1, get_pointer(s_sum_acc_ct1), work_group_size);
+ });
+ });
+ }
+}
+
+static void l2_norm_f32_sycl(const float* x, float* dst, const int ncols,
+ const int nrows, const float eps,
+ queue_ptr stream, int device) {
+ // printf("%s ncols=%d, nrows=%d, WARP_SIZE=%d\n", __func__, ncols, nrows, WARP_SIZE);
+ if (ncols < 1024) {
+ const sycl::range<3> block_dims(1, 1, WARP_SIZE);
+ stream->submit([&](sycl::handler& cgh) {
+ cgh.parallel_for(
+ sycl::nd_range<3>(sycl::range<3>(1, 1, nrows) * block_dims,
+ block_dims),
+ [=](sycl::nd_item<3> item_ct1)
+ [[sycl::reqd_sub_group_size(WARP_SIZE)]] {
+ l2_norm_f32(x, dst, ncols, eps, item_ct1,
+ nullptr, WARP_SIZE);
+ });
+ });
+ }
+ else {
+ const int work_group_size = ggml_sycl_info().max_work_group_sizes[device];
+ assert(work_group_size % (WARP_SIZE * WARP_SIZE) == 0);
+ const sycl::range<3> block_dims(1, 1, work_group_size);
+ /*
+ DPCT1049:19: The work-group size passed to the SYCL kernel may exceed
+ the limit. To get the device limit, query
+ info::device::max_work_group_size. Adjust the work-group size if needed.
+ */
+ stream->submit([&](sycl::handler& cgh) {
+ sycl::local_accessor<float, 1> s_sum_acc_ct1(sycl::range<1>(work_group_size / WARP_SIZE),
+ cgh);
+ cgh.parallel_for(
+ sycl::nd_range<3>(sycl::range<3>(1, 1, nrows) * block_dims,
+ block_dims),
+ [=](sycl::nd_item<3> item_ct1)
+ [[sycl::reqd_sub_group_size(WARP_SIZE)]] {
+ l2_norm_f32(x, dst, ncols, eps, item_ct1,
+ get_pointer(s_sum_acc_ct1), work_group_size);
+ });
+ });
+ }
+}
+
+void ggml_sycl_op_norm(ggml_backend_sycl_context& ctx, ggml_tensor* dst) {
+ const ggml_tensor * src0 = dst->src[0];
+
+ GGML_ASSERT(dst->src[0]->type == GGML_TYPE_F32);
+ GGML_ASSERT(dst->type == GGML_TYPE_F32);
+
+ GGML_TENSOR_UNARY_OP_LOCALS
+ dpct::queue_ptr main_stream = ctx.stream();
+ SYCL_CHECK(ggml_sycl_set_device(ctx.device));
+ const float * src0_dd = static_cast<const float *>(dst->src[0]->data);
+ float * dst_dd = static_cast<float *>(dst->data);
+
+ float eps;
+ memcpy(&eps, dst->op_params, sizeof(float));
+ GGML_ASSERT(eps >= 0.0f);
+ const size_t ts0 = ggml_type_size(src0->type);
+ GGML_ASSERT(nb00 == ts0);
+ const int64_t s01 = nb01 / ts0;
+ const int64_t s02 = nb02 / ts0;
+ const int64_t s03 = nb03 / ts0;
+
+ norm_f32_sycl(src0_dd, dst_dd, ne00, ne01, ne02, ne03, s01, s02, s03, eps, main_stream, ctx.device);
+}
+
+void ggml_sycl_op_group_norm(ggml_backend_sycl_context& ctx, ggml_tensor* dst) {
+
+ GGML_ASSERT(dst->src[0]->type == GGML_TYPE_F32);
+ GGML_ASSERT(dst->type == GGML_TYPE_F32);
+
+ int num_groups = dst->op_params[0];
+ dpct::queue_ptr main_stream = ctx.stream();
+ SYCL_CHECK(ggml_sycl_set_device(ctx.device));
+
+ const float * src0_dd = static_cast<const float *>(dst->src[0]->data);
+ float * dst_dd = static_cast<float *>(dst->data);
+
+ float eps;
+ memcpy(&eps, dst->op_params + 1, sizeof(float));
+
+ int group_size = dst->src[0]->ne[0] * dst->src[0]->ne[1] * ((dst->src[0]->ne[2] + num_groups - 1) / num_groups);
+ group_norm_f32_sycl(src0_dd, dst_dd, num_groups, eps, group_size, dst->src[0]->ne[0] * dst->src[0]->ne[1] * dst->src[0]->ne[2], main_stream, ctx.device);
+}
+
+void ggml_sycl_op_rms_norm(ggml_backend_sycl_context & ctx, ggml_tensor * dst) {
+
+ const ggml_tensor * src0 = dst->src[0];
+ GGML_ASSERT(dst->src[0]->type == GGML_TYPE_F32);
+ GGML_ASSERT(dst->type == GGML_TYPE_F32);
+
+ dpct::queue_ptr main_stream = ctx.stream();
+ SYCL_CHECK(ggml_sycl_set_device(ctx.device));
+
+ const float * src0_dd = static_cast<const float *>(dst->src[0]->data);
+ float * dst_dd = static_cast<float *>(dst->data);
+
+ float eps;
+ memcpy(&eps, dst->op_params, sizeof(float));
+
+ GGML_TENSOR_UNARY_OP_LOCALS
+ const size_t ts0 = ggml_type_size(src0->type);
+ GGML_ASSERT(nb00 == ts0);
+ const int64_t s01 = nb01 / ts0;
+ const int64_t s02 = nb02 / ts0;
+ const int64_t s03 = nb03 / ts0;
+ rms_norm_f32_sycl(src0_dd, dst_dd, ne00, ne01, ne02, ne03, s01, s02, s03, eps, main_stream, ctx.device);
+}
+
+void ggml_sycl_op_rms_norm_back(ggml_backend_sycl_context & ctx, ggml_tensor * dst) {
+ scope_op_debug_print scope_dbg_print(__func__, dst, /*num_src=*/2);
+
+ GGML_ASSERT(dst->src[0]->type == GGML_TYPE_F32); // dz
+ GGML_ASSERT(dst->src[1]->type == GGML_TYPE_F32); // x
+ GGML_ASSERT(dst->type == GGML_TYPE_F32);
+
+ float eps = 1e-5f;
+ std::memcpy(&eps, dst->op_params, sizeof(float));
+ if (!(eps > 0.0f) || !std::isfinite(eps)) eps = 1e-5f;
+
+ const float * g_base = static_cast<const float *>(dst->src[0]->data); // dz
+ const float * x_base = static_cast<const float *>(dst->src[1]->data); // x
+ float * dx_base = static_cast< float *>(dst->data);
+
+ const int64_t D = dst->ne[0];
+ const int64_t n1 = dst->ne[1], n2 = dst->ne[2], n3 = dst->ne[3]; (void) n3;
+ const int64_t N = ggml_nrows(dst);
+ if (D == 0 || N == 0) return;
+
+ const ggml_tensor *G = dst->src[0];
+ const ggml_tensor *X = dst->src[1];
+ const int ts = (int) ggml_type_size(X->type);
+ GGML_ASSERT((size_t) X->nb[0] == (size_t) ts);
+ GGML_ASSERT((size_t) G->nb[0] == (size_t) ts);
+ GGML_ASSERT((size_t) dst->nb[0] == (size_t) ts);
+
+ const int64_t xs1 = X->nb[1] / ts, xs2 = X->nb[2] / ts, xs3 = X->nb[3] / ts;
+ const int64_t gs1 = G->nb[1] / ts, gs2 = G->nb[2] / ts, gs3 = G->nb[3] / ts;
+ const int64_t ds1 = dst->nb[1] / ts, ds2 = dst->nb[2] / ts, ds3 = dst->nb[3] / ts;
+
+ dpct::queue_ptr q = ctx.stream();
+
+ // work-group size: multiple of WARP_SIZE, capped by device and 256, and not larger than D
+ const int device_max_wg = ggml_sycl_info().max_work_group_sizes[ctx.device];
+ auto roundup = [](int v, int m) { return ((v + m - 1) / m) * m; };
+ int wg_cap = 256;
+ if (device_max_wg > 0) wg_cap = std::min(wg_cap, device_max_wg);
+ int WG = std::max(WARP_SIZE, std::min(roundup((int)std::min<int64_t>(D, wg_cap), WARP_SIZE), wg_cap));
+
+ // FP32 path: per-thread compensated accumulation + hierarchical reduction
+ q->submit([&](sycl::handler &cgh) {
+ const int nwarps_loc = std::max(1, WG / WARP_SIZE);
+ // store one partial value per warp (xx and xg) for cross-warp reduction
+ auto l_xx = sycl::local_accessor<sycl::float2, 1>(sycl::range<1>(nwarps_loc), cgh);
+ auto l_xg = sycl::local_accessor<sycl::float2, 1>(sycl::range<1>(nwarps_loc), cgh);
+
+ cgh.parallel_for(
+ sycl::nd_range<3>(sycl::range<3>(1, 1, N) * sycl::range<3>(1, 1, WG),
+ sycl::range<3>(1, 1, WG)),
+ [=](sycl::nd_item<3> item_ct1) [[sycl::reqd_sub_group_size(WARP_SIZE)]] {
+ const int row = item_ct1.get_group(2);
+ const int tid = item_ct1.get_local_id(2);
+
+ const int64_t i1 = row % n1;
+ const int64_t i2 = (row / n1) % n2;
+ const int64_t i3 = row / (n1 * n2);
+
+ const float *__restrict x_row = x_base + i3 * xs3 + i2 * xs2 + i1 * xs1;
+ const float *__restrict g_row = g_base + i3 * gs3 + i2 * gs2 + i1 * gs1;
+ float *__restrict d_row = dx_base + i3 * ds3 + i2 * ds2 + i1 * ds1;
+
+ // per-thread accumulation (compensated by default)
+ float sum_xx = 0.f, sum_xg = 0.f;
+#ifndef GGML_SYCL_RMS_BACK_FAST
+ float c_xx = 0.f, c_xg = 0.f;
+#endif
+ for (int64_t col = tid; col < D; col += WG) {
+ const float xv = x_row[col];
+ const float gv = g_row[col];
+#ifdef GGML_SYCL_RMS_BACK_FAST
+ sum_xx += xv * xv;
+ sum_xg += xv * gv;
+#else
+ float y1 = xv * xv - c_xx;
+ float t1 = sum_xx + y1;
+ c_xx = (t1 - sum_xx) - y1;
+ sum_xx = t1;
+
+ float y2 = xv * gv - c_xg;
+ float t2 = sum_xg + y2;
+ c_xg = (t2 - sum_xg) - y2;
+ sum_xg = t2;
+#endif
+ }
+
+ // warp-level reduction
+ sycl::float2 xx = sycl::float2(sum_xx,
+#ifndef GGML_SYCL_RMS_BACK_FAST
+ c_xx
+#else
+ 0.f
+#endif
+ );
+ sycl::float2 xg = sycl::float2(sum_xg,
+#ifndef GGML_SYCL_RMS_BACK_FAST
+ c_xg
+#else
+ 0.f
+#endif
+ );
+ xx = warp_reduce_sum(xx, item_ct1);
+ xg = warp_reduce_sum(xg, item_ct1);
+
+ // cross-warp reduction using local memory (single barrier)
+ const auto sub_group = item_ct1.get_sub_group();
+ const auto sg_id = sub_group.get_group_linear_id();
+ const auto wi_in_sg = sub_group.get_local_linear_id();
+ const int nthreads = item_ct1.get_local_range(2);
+ const int nwarps = nthreads / WARP_SIZE;
+
+ sycl::float2 xx_total = xx;
+ sycl::float2 xg_total = xg;
+ if (nwarps > 1) {
+ if (wi_in_sg == 0) {
+ l_xx[sg_id] = xx;
+ l_xg[sg_id] = xg;
+ }
+ item_ct1.barrier(sycl::access::fence_space::local_space);
+
+ if (sg_id == 0) {
+ const unsigned wi_u = wi_in_sg;
+ sycl::float2 xx_first = (wi_u < static_cast<unsigned>(nwarps)) ? l_xx[wi_u] : sycl::float2(0.f, 0.f);
+ sycl::float2 xg_first = (wi_u < static_cast<unsigned>(nwarps)) ? l_xg[wi_u] : sycl::float2(0.f, 0.f);
+ xx_total = warp_reduce_sum(xx_first, item_ct1);
+ xg_total = warp_reduce_sum(xg_first, item_ct1);
+ } else {
+ // other subgroups keep their local totals; they'll be ignored
+ xx_total = xx;
+ xg_total = xg;
+ }
+ // ensure all threads see the first-subgroup result via broadcast below
+ }
+
+ // compute inv_r and coeff once per row and broadcast to the whole work-group
+ float inv_r = 0.f;
+ float coeff = 0.f;
+ if (tid == 0) {
+ const float sum_xx_f = xx_total.x() + xx_total.y();
+ const float sum_xdz_f = xg_total.x() + xg_total.y();
+ const float mean_eps = sum_xx_f / (float) D + eps;
+ const float sum_eps = sum_xx_f + eps * (float) D;
+ inv_r = sycl::rsqrt(mean_eps);
+ coeff = -sum_xdz_f / sum_eps;
+ }
+ inv_r = sycl::group_broadcast(item_ct1.get_group(), inv_r);
+ coeff = sycl::group_broadcast(item_ct1.get_group(), coeff);
+
+ for (int64_t col = tid; col < D; col += WG) {
+ d_row[col] = (g_row[col] + coeff * x_row[col]) * inv_r;
+ }
+ });
+ });
+
+}
+
+void ggml_sycl_op_l2_norm(ggml_backend_sycl_context& ctx, ggml_tensor* dst) {
+
+ GGML_ASSERT(dst->src[0]->type == GGML_TYPE_F32);
+ GGML_ASSERT(dst->type == GGML_TYPE_F32);
+
+ dpct::queue_ptr main_stream = ctx.stream();
+ SYCL_CHECK(ggml_sycl_set_device(ctx.device));
+
+ const int64_t ne00 = dst->src[0]->ne[0];
+ const int64_t nrows = ggml_nrows(dst->src[0]);
+ const float * src0_dd = static_cast<const float *>(dst->src[0]->data);
+ float * dst_dd = static_cast<float *>(dst->data);
+
+ float eps;
+ memcpy(&eps, dst->op_params, sizeof(float));
+
+ l2_norm_f32_sycl(src0_dd, dst_dd, ne00, nrows, eps, main_stream, ctx.device);
+
+}