llama.cpp/ggml-opencl-dequant.cl

#define MULTILINE_QUOTE(...) #__VA_ARGS__
const char * clblast_dequant = MULTILINE_QUOTE(

struct block_q4_0
{
    float d;
    uchar qs[16];
};

__kernel void dequantize_row_q4_0(__global struct block_q4_0* blocks, __global float* result) {
    const uint i = get_global_id(0) / 32;
    const uint l = get_local_id(0);

    const float d = blocks[i].d;

    const uchar vi = blocks[i].qs[l];

    const uint index = i*32 + l*2;
    result[index + 0] = ((vi & 0xf) - 8)*d;
    result[index + 1] = ((vi >> 4) - 8)*d;
}

struct block_q4_1
{
    float d;
    float m;
    uchar qs[16];
};

__kernel void dequantize_row_q4_1(__global struct block_q4_1* blocks, __global float* result) {
    const uint i = get_global_id(0) / 32;
    const uint l = get_local_id(0);

    const float d = blocks[i].d;
    const float m = blocks[i].m;

    const uchar vi = blocks[i].qs[l];

    const uint index = i*32 + l*2;
    result[index + 0] = (vi & 0xf) * d + m;
    result[index + 1] = (vi >> 4) * d + m;
}

struct block_q4_2
{
    ushort d;
    uchar qs[8];
};

__kernel void dequantize_row_q4_2(__global struct block_q4_2* blocks, __global float* result) {
    const uint i = get_global_id(0) / 16;
    const uint l = get_local_id(0);

    const float d = vload_half(0, (__global half*) &blocks[i].d);;

    const uchar vi = blocks[i].qs[l];

    const uint index = i*16 + l*2;
    result[index + 0] = ((vi & 0xf) - 8)*d;
    result[index + 1] = ((vi >> 4) - 8)*d;
}

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