embedding_kernels_bf16.c File Reference

Token/position embedding lookup kernels for BF16. More...

#include <stdint.h>
#include <string.h>
#include "bf16_utils.h"
#include "ckernel_engine.h"

Go to the source code of this file.

Functions
void	embedding_backward_bf16 (const int32_t *token_ids, int token_count, const uint16_t *d_output, uint16_t *d_token_embeddings, uint16_t *d_pos_embeddings, int vocab_size, int embed_dim, int aligned_embed_dim, int context_window, int add_pos)
void	embedding_forward_bf16 (const int32_t *token_ids, int token_count, int vocab_size, const uint16_t *token_embeddings, const uint16_t *pos_embeddings, uint16_t *output, int embed_dim, int aligned_embed_dim, int context_window, int add_pos)

Detailed Description

Token/position embedding lookup kernels for BF16.

CK-ENGINE KERNEL RULES:

1. NO malloc/free - memory via bump allocator, pointers passed in
2. NO OpenMP - parallelization at orchestrator/codegen layer
3. API must define: inputs, outputs, workspace, and memory layouts
4. Pure computation - deterministic, no side effects

After changes: make test && make llamacpp-parity-full

Definition in file embedding_kernels_bf16.c.

Function Documentation

embedding_backward_bf16()

void embedding_backward_bf16	(	const int32_t *	token_ids,
		int	token_count,
		const uint16_t *	d_output,
		uint16_t *	d_token_embeddings,
		uint16_t *	d_pos_embeddings,
		int	vocab_size,
		int	embed_dim,
		int	aligned_embed_dim,
		int	context_window,
		int	add_pos
	)

Definition at line 72 of file embedding_kernels_bf16.c.

{
    if (!token_ids || !d_output || !d_token_embeddings) {
        return;
    }
 
    int tokens = token_count;
    if (tokens < 0) tokens = 0;
    if (tokens > context_window) tokens = context_window;
 
    for (int t = 0; t < tokens; ++t) {
        int id = token_ids[t];
        if (id < 0 || id >= vocab_size) {
            id = 0;
        }
 
        const uint16_t *d_out = d_output + (size_t)t * (size_t)aligned_embed_dim;
        uint16_t *d_tok = d_token_embeddings + (size_t)id * (size_t)aligned_embed_dim;
        uint16_t *d_pos = d_pos_embeddings ? (d_pos_embeddings + (size_t)t * (size_t)aligned_embed_dim) : NULL;
 
        for (int d = 0; d < embed_dim; ++d) {
            float grad = bf16_to_float(d_out[d]);
 
            float cur_tok = bf16_to_float(d_tok[d]);
            d_tok[d] = float_to_bf16(cur_tok + grad);
 
            if (add_pos && d_pos) {
                float cur_pos = bf16_to_float(d_pos[d]);
                d_pos[d] = float_to_bf16(cur_pos + grad);
            }
        }
    }
}

References bf16_to_float(), float_to_bf16(), and vocab_size.

embedding_forward_bf16()

void embedding_forward_bf16	(	const int32_t *	token_ids,
		int	token_count,
		int	vocab_size,
		const uint16_t *	token_embeddings,
		const uint16_t *	pos_embeddings,
		uint16_t *	output,
		int	embed_dim,
		int	aligned_embed_dim,
		int	context_window,
		int	add_pos
	)

Definition at line 21 of file embedding_kernels_bf16.c.

{
    if (!token_ids || !token_embeddings || !output) {
        return;
    }
 
    int tokens = token_count;
    if (tokens < 0) tokens = 0;
    if (tokens > context_window) tokens = context_window;
 
    for (int t = 0; t < tokens; ++t) {
        int id = token_ids[t];
        if (id < 0 || id >= vocab_size) {
            id = 0;
        }
 
        const uint16_t *tok = token_embeddings + (size_t)id * (size_t)aligned_embed_dim;
        const uint16_t *pos = pos_embeddings ? (pos_embeddings + (size_t)t * (size_t)aligned_embed_dim) : NULL;
        uint16_t *out = output + (size_t)t * (size_t)aligned_embed_dim;
 
        if (add_pos && pos) {
            for (int d = 0; d < embed_dim; ++d) {
                float v = bf16_to_float(tok[d]) + bf16_to_float(pos[d]);
                out[d] = float_to_bf16(v);
            }
        } else {
            for (int d = 0; d < embed_dim; ++d) {
                out[d] = tok[d];
            }
        }
 
        for (int d = embed_dim; d < aligned_embed_dim; ++d) {
            out[d] = 0;
        }
    }
 
    for (int t = tokens; t < context_window; ++t) {
        uint16_t *out = output + (size_t)t * (size_t)aligned_embed_dim;
        memset(out, 0, (size_t)aligned_embed_dim * sizeof(uint16_t));
    }
}

References bf16_to_float(), float_to_bf16(), and vocab_size.