[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Explain what this code does and identify the inference stage it belongs to.

File: ds4_metal.m

```c
f (ok) {
            ok = ds4_gpu_encode_set_rows_f32_i32(cb,
                                                   state_kv,
                                                   kvbuf,
                                                   ds4_gpu_tensor_offset(kv),
                                                   rows,
                                                   n_tokens,
                                                   state_rows,
                                                   width);
        }
        if (ok) {
            ok = ds4_gpu_encode_set_rows_f32_i32(cb,
                                                   state_score,
                                                   g_compressor_store_score_buffer,
                                                   0,
                                                   rows,
                                                   n_tokens,
                                                   state_rows,
                                                   width);
        }
        if (rows != rows_stack) free(rows);
        if (!ok) return 0;

        if (!ds4_gpu_finish_command_buffer(cb, owned, "compressor batch DS4 store")) return 0;
    }

    return 1;
}

static ds4_gpu_bin_args ds4_gpu_make_bin_contiguous_3d_args(
        uint32_t cols,
        uint32_t rows,
        uint32_t planes) {
    const uint64_t row_bytes = (uint64_t)cols * sizeof(float);
    const uint64_t plane_bytes = (uint64_t)rows * row_bytes;
    return (ds4_gpu_bin_args) {
        .ne00 = (int32_t)cols,
        .ne01 = (int32_t)rows,
        .ne02 = (int32_t)planes,
        .ne03 = 1,
        .nb00 = sizeof(float),
        .nb01 = row_bytes,
        .nb02 = plane_bytes,
        .nb03 = (uint64_t)planes * plane_bytes,
        .ne10 = (int32_t)cols,
        .ne11 = (int32_t)rows,
        .ne12 = (int32_t)planes,
        .ne13 = 1,
        .nb10 = sizeof(float),
        .nb11 = row_bytes,
        .nb12 = plane_bytes,
        .nb13 = (uint64_t)planes * plane_bytes,
        .ne0 = (int32_t)cols,
        .ne1 = (int32_t)rows,
        .ne2 = (int32_t)planes,
        .ne3 = 1,
        .nb0 = sizeof(float),
        .nb1 = row_bytes,
        .nb2 = plane_bytes,
        .nb3 = (uint64_t)planes * plane_bytes,
        .offs = 0,
        .o1 = { 0 },
    };
}

static int ds4_gpu_encode_softmax_f32_contiguous(
        id<MTLCommandBuffer> cb,
        id<MTLBuffer>        src,
        NSUInteger           src_off,
        id<MTLBuffer>        dst,
        NSUInteger           dst_off,
        uint32_t             width,
        uint32_t             rows,
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Explain what this code does and identify the inference stage it belongs to.

File: ds4_metal.m

```c
f (ok) {
            ok = ds4_gpu_encode_set_rows_f32_i32(cb,
                                                   state_kv,
                                                   kvbuf,
                                                   ds4_gpu_tensor_offset(kv),
                                                   rows,
                                                   n_tokens,
                                                   state_rows,
                                                   width);
        }
        if (ok) {
            ok = ds4_gpu_encode_set_rows_f32_i32(cb,
                                                   state_score,
                                                   g_compressor_store_score_buffer,
                                                   0,
                                                   rows,
                                                   n_tokens,
                                                   state_rows,
                                                   width);
        }
        if (rows != rows_stack) free(rows);
        if (!ok) return 0;

        if (!ds4_gpu_finish_command_buffer(cb, owned, "compressor batch DS4 store")) return 0;
    }

    return 1;
}

static ds4_gpu_bin_args ds4_gpu_make_bin_contiguous_3d_args(
        uint32_t cols,
        uint32_t rows,
        uint32_t planes) {
    const uint64_t row_bytes = (uint64_t)cols * sizeof(float);
    const uint64_t plane_bytes = (uint64_t)rows * row_bytes;
    return (ds4_gpu_bin_args) {
        .ne00 = (int32_t)cols,
        .ne01 = (int32_t)rows,
        .ne02 = (int32_t)planes,
        .ne03 = 1,
        .nb00 = sizeof(float),
        .nb01 = row_bytes,
        .nb02 = plane_bytes,
        .nb03 = (uint64_t)planes * plane_bytes,
        .ne10 = (int32_t)cols,
        .ne11 = (int32_t)rows,
        .ne12 = (int32_t)planes,
        .ne13 = 1,
        .nb10 = sizeof(float),
        .nb11 = row_bytes,
        .nb12 = plane_bytes,
        .nb13 = (uint64_t)planes * plane_bytes,
        .ne0 = (int32_t)cols,
        .ne1 = (int32_t)rows,
        .ne2 = (int32_t)planes,
        .ne3 = 1,
        .nb0 = sizeof(float),
        .nb1 = row_bytes,
        .nb2 = plane_bytes,
        .nb3 = (uint64_t)planes * plane_bytes,
        .offs = 0,
        .o1 = { 0 },
    };
}

static int ds4_gpu_encode_softmax_f32_contiguous(
        id<MTLCommandBuffer> cb,
        id<MTLBuffer>        src,
        NSUInteger           src_off,
        id<MTLBuffer>        dst,
        NSUInteger           dst_off,
        uint32_t             width,
        uint32_t             rows,
```<｜Assistant｜><think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Suggest a minimal correctness-preserving optimization for this excerpt.

File: ds4_metal.m

```c
NSUInteger           src_off,
        id<MTLBuffer>        dst,
        NSUInteger           dst_off,
        uint32_t             width,
        uint32_t             rows,
        uint32_t             planes) {
    if (!cb || !src || !dst || width == 0 || rows == 0 || planes == 0) return 0;

    const uint64_t row_bytes = (uint64_t)width * sizeof(float);
    const uint64_t plane_bytes = (uint64_t)rows * row_bytes;
    ds4_gpu_softmax_args args = {
        .ne00 = (int32_t)width,
        .ne01 = (int32_t)rows,
        .ne02 = (int32_t)planes,
        .nb01 = row_bytes,
        .nb02 = plane_bytes,
        .nb03 = (uint64_t)planes * plane_bytes,
        .ne11 = (int32_t)width,
        .ne12 = (int32_t)rows,
        .ne13 = (int32_t)planes,
        .nb11 = row_bytes,
        .nb12 = plane_bytes,
        .nb13 = (uint64_t)planes * plane_bytes,
        .nb1 = row_bytes,
        .nb2 = plane_bytes,
        .nb3 = (uint64_t)planes * plane_bytes,
        .scale = 1.0f,
        .max_bias = 0.0f,
        .m0 = 0.0f,
        .m1 = 0.0f,
        .n_head_log2 = 1,
    };

    id<MTLComputePipelineState> pipeline =
        (width % 4u) == 0 ? g_soft_max_f32_4_pipeline : g_soft_max_f32_pipeline;
    if (!pipeline) return 0;

    NSUInteger nth = 32u;
    if ((width % 4u) == 0) {
        while (nth < (NSUInteger)(width / 4u) &&
               nth * (NSUInteger)rows * (NSUInteger)planes < 256u) {
            nth *= 2u;
        }
    } else {
        while (nth < (NSUInteger)width &&
               nth * (NSUInteger)rows * (NSUInteger)planes < 256u) {
            nth *= 2u;
        }
    }
    const NSUInteger max_threads = pipeline.maxTotalThreadsPerThreadgroup;
    if (nth > max_threads) nth = max_threads;
    if (nth == 0) nth = 1u;

    id<MTLComputeCommandEncoder> enc = ds4_gpu_compute_encoder(cb);
    [enc setComputePipelineState:pipeline];
    [enc setBytes:&args length:sizeof(args) atIndex:0];
    [enc setBuffer:src offset:src_off atIndex:1];
    [enc setBuffer:src offset:src_off atIndex:2];
    [enc setBuffer:src offset:src_off atIndex:3];
    [enc setBuffer:dst offset:dst_off atIndex:4];
    [enc setThreadgroupMemoryLength:32u * sizeof(float) atIndex:0];
    [enc dispatchThreadgroups:MTLSizeMake(rows, planes, 1)
         threadsPerThreadgroup:MTLSizeMake(nth, 1, 1)];
    ds4_gpu_end_compute_encoder(cb, enc);
    return 1;
}

static int ds4_gpu_encode_dsv4_softmax_pool_one_comp_ggml(
        id<MTLCommandBuffer> cb,
        ds4_gpu_tensor    *out,
        id<MTLBuffer>        kvbuf,
        NSUInteger           kv_offset,
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Suggest a minimal correctness-preserving optimization for this excerpt.

File: ds4_metal.m

```c
NSUInteger           src_off,
        id<MTLBuffer>        dst,
        NSUInteger           dst_off,
        uint32_t             width,
        uint32_t             rows,
        uint32_t             planes) {
    if (!cb || !src || !dst || width == 0 || rows == 0 || planes == 0) return 0;

    const uint64_t row_bytes = (uint64_t)width * sizeof(float);
    const uint64_t plane_bytes = (uint64_t)rows * row_bytes;
    ds4_gpu_softmax_args args = {
        .ne00 = (int32_t)width,
        .ne01 = (int32_t)rows,
        .ne02 = (int32_t)planes,
        .nb01 = row_bytes,
        .nb02 = plane_bytes,
        .nb03 = (uint64_t)planes * plane_bytes,
        .ne11 = (int32_t)width,
        .ne12 = (int32_t)rows,
        .ne13 = (int32_t)planes,
        .nb11 = row_bytes,
        .nb12 = plane_bytes,
        .nb13 = (uint64_t)planes * plane_bytes,
        .nb1 = row_bytes,
        .nb2 = plane_bytes,
        .nb3 = (uint64_t)planes * plane_bytes,
        .scale = 1.0f,
        .max_bias = 0.0f,
        .m0 = 0.0f,
        .m1 = 0.0f,
        .n_head_log2 = 1,
    };

    id<MTLComputePipelineState> pipeline =
        (width % 4u) == 0 ? g_soft_max_f32_4_pipeline : g_soft_max_f32_pipeline;
    if (!pipeline) return 0;

    NSUInteger nth = 32u;
    if ((width % 4u) == 0) {
        while (nth < (NSUInteger)(width / 4u) &&
               nth * (NSUInteger)rows * (NSUInteger)planes < 256u) {
            nth *= 2u;
        }
    } else {
        while (nth < (NSUInteger)width &&
               nth * (NSUInteger)rows * (NSUInteger)planes < 256u) {
            nth *= 2u;
        }
    }
    const NSUInteger max_threads = pipeline.maxTotalThreadsPerThreadgroup;
    if (nth > max_threads) nth = max_threads;
    if (nth == 0) nth = 1u;

    id<MTLComputeCommandEncoder> enc = ds4_gpu_compute_encoder(cb);
    [enc setComputePipelineState:pipeline];
    [enc setBytes:&args length:sizeof(args) atIndex:0];
    [enc setBuffer:src offset:src_off atIndex:1];
    [enc setBuffer:src offset:src_off atIndex:2];
    [enc setBuffer:src offset:src_off atIndex:3];
    [enc setBuffer:dst offset:dst_off atIndex:4];
    [enc setThreadgroupMemoryLength:32u * sizeof(float) atIndex:0];
    [enc dispatchThreadgroups:MTLSizeMake(rows, planes, 1)
         threadsPerThreadgroup:MTLSizeMake(nth, 1, 1)];
    ds4_gpu_end_compute_encoder(cb, enc);
    return 1;
}

static int ds4_gpu_encode_dsv4_softmax_pool_one_comp_ggml(
        id<MTLCommandBuffer> cb,
        ds4_gpu_tensor    *out,
        id<MTLBuffer>        kvbuf,
        NSUInteger           kv_offset,
```<｜Assistant｜></think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Suggest a minimal correctness-preserving optimization for this excerpt.

File: ds4_metal.m

```c
NSUInteger           src_off,
        id<MTLBuffer>        dst,
        NSUInteger           dst_off,
        uint32_t             width,
        uint32_t             rows,
        uint32_t             planes) {
    if (!cb || !src || !dst || width == 0 || rows == 0 || planes == 0) return 0;

    const uint64_t row_bytes = (uint64_t)width * sizeof(float);
    const uint64_t plane_bytes = (uint64_t)rows * row_bytes;
    ds4_gpu_softmax_args args = {
        .ne00 = (int32_t)width,
        .ne01 = (int32_t)rows,
        .ne02 = (int32_t)planes,
        .nb01 = row_bytes,
        .nb02 = plane_bytes,
        .nb03 = (uint64_t)planes * plane_bytes,
        .ne11 = (int32_t)width,
        .ne12 = (int32_t)rows,
        .ne13 = (int32_t)planes,
        .nb11 = row_bytes,
        .nb12 = plane_bytes,
        .nb13 = (uint64_t)planes * plane_bytes,
        .nb1 = row_bytes,
        .nb2 = plane_bytes,
        .nb3 = (uint64_t)planes * plane_bytes,
        .scale = 1.0f,
        .max_bias = 0.0f,
        .m0 = 0.0f,
        .m1 = 0.0f,
        .n_head_log2 = 1,
    };

    id<MTLComputePipelineState> pipeline =
        (width % 4u) == 0 ? g_soft_max_f32_4_pipeline : g_soft_max_f32_pipeline;
    if (!pipeline) return 0;

    NSUInteger nth = 32u;
    if ((width % 4u) == 0) {
        while (nth < (NSUInteger)(width / 4u) &&
               nth * (NSUInteger)rows * (NSUInteger)planes < 256u) {
            nth *= 2u;
        }
    } else {
        while (nth < (NSUInteger)width &&
               nth * (NSUInteger)rows * (NSUInteger)planes < 256u) {
            nth *= 2u;
        }
    }
    const NSUInteger max_threads = pipeline.maxTotalThreadsPerThreadgroup;
    if (nth > max_threads) nth = max_threads;
    if (nth == 0) nth = 1u;

    id<MTLComputeCommandEncoder> enc = ds4_gpu_compute_encoder(cb);
    [enc setComputePipelineState:pipeline];
    [enc setBytes:&args length:sizeof(args) atIndex:0];
    [enc setBuffer:src offset:src_off atIndex:1];
    [enc setBuffer:src offset:src_off atIndex:2];
    [enc setBuffer:src offset:src_off atIndex:3];
    [enc setBuffer:dst offset:dst_off atIndex:4];
    [enc setThreadgroupMemoryLength:32u * sizeof(float) atIndex:0];
    [enc dispatchThreadgroups:MTLSizeMake(rows, planes, 1)
         threadsPerThreadgroup:MTLSizeMake(nth, 1, 1)];
    ds4_gpu_end_compute_encoder(cb, enc);
    return 1;
}

static int ds4_gpu_encode_dsv4_softmax_pool_one_comp_ggml(
        id<MTLCommandBuffer> cb,
        ds4_gpu_tensor    *out,
        id<MTLBuffer>        kvbuf,
        NSUInteger           kv_offset,
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Suggest a minimal correctness-preserving optimization for this excerpt.

File: ds4_metal.m

```c
NSUInteger           src_off,
        id<MTLBuffer>        dst,
        NSUInteger           dst_off,
        uint32_t             width,
        uint32_t             rows,
        uint32_t             planes) {
    if (!cb || !src || !dst || width == 0 || rows == 0 || planes == 0) return 0;

    const uint64_t row_bytes = (uint64_t)width * sizeof(float);
    const uint64_t plane_bytes = (uint64_t)rows * row_bytes;
    ds4_gpu_softmax_args args = {
        .ne00 = (int32_t)width,
        .ne01 = (int32_t)rows,
        .ne02 = (int32_t)planes,
        .nb01 = row_bytes,
        .nb02 = plane_bytes,
        .nb03 = (uint64_t)planes * plane_bytes,
        .ne11 = (int32_t)width,
        .ne12 = (int32_t)rows,
        .ne13 = (int32_t)planes,
        .nb11 = row_bytes,
        .nb12 = plane_bytes,
        .nb13 = (uint64_t)planes * plane_bytes,
        .nb1 = row_bytes,
        .nb2 = plane_bytes,
        .nb3 = (uint64_t)planes * plane_bytes,
        .scale = 1.0f,
        .max_bias = 0.0f,
        .m0 = 0.0f,
        .m1 = 0.0f,
        .n_head_log2 = 1,
    };

    id<MTLComputePipelineState> pipeline =
        (width % 4u) == 0 ? g_soft_max_f32_4_pipeline : g_soft_max_f32_pipeline;
    if (!pipeline) return 0;

    NSUInteger nth = 32u;
    if ((width % 4u) == 0) {
        while (nth < (NSUInteger)(width / 4u) &&
               nth * (NSUInteger)rows * (NSUInteger)planes < 256u) {
            nth *= 2u;
        }
    } else {
        while (nth < (NSUInteger)width &&
               nth * (NSUInteger)rows * (NSUInteger)planes < 256u) {
            nth *= 2u;
        }
    }
    const NSUInteger max_threads = pipeline.maxTotalThreadsPerThreadgroup;
    if (nth > max_threads) nth = max_threads;
    if (nth == 0) nth = 1u;

    id<MTLComputeCommandEncoder> enc = ds4_gpu_compute_encoder(cb);
    [enc setComputePipelineState:pipeline];
    [enc setBytes:&args length:sizeof(args) atIndex:0];
    [enc setBuffer:src offset:src_off atIndex:1];
    [enc setBuffer:src offset:src_off atIndex:2];
    [enc setBuffer:src offset:src_off atIndex:3];
    [enc setBuffer:dst offset:dst_off atIndex:4];
    [enc setThreadgroupMemoryLength:32u * sizeof(float) atIndex:0];
    [enc dispatchThreadgroups:MTLSizeMake(rows, planes, 1)
         threadsPerThreadgroup:MTLSizeMake(nth, 1, 1)];
    ds4_gpu_end_compute_encoder(cb, enc);
    return 1;
}

static int ds4_gpu_encode_dsv4_softmax_pool_one_comp_ggml(
        id<MTLCommandBuffer> cb,
        ds4_gpu_tensor    *out,
        id<MTLBuffer>        kvbuf,
        NSUInteger           kv_offset,
```<｜Assistant｜><think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Trova bug sottili e spiega quali invarianti dell'inferenza possono rompersi.

File: ds4_metal.m

```c
encode_dsv4_softmax_pool_one_comp_ggml(
        id<MTLCommandBuffer> cb,
        ds4_gpu_tensor    *out,
        id<MTLBuffer>        kvbuf,
        NSUInteger           kv_offset,
        uint64_t             kv_nb0,
        uint64_t             kv_nb1,
        uint64_t             kv_nb2,
        id<MTLBuffer>        scorebuf,
        NSUInteger           score_offset,
        uint64_t             score_nb0,
        uint64_t             score_nb1,
        uint64_t             score_nb2,
        uint32_t             n_rows,
        uint32_t             head_dim) {
    id<MTLBuffer> outbuf = ds4_gpu_tensor_buffer(out);
    if (!cb || !outbuf || !kvbuf || !scorebuf || n_rows == 0 || head_dim == 0 ||
        ds4_gpu_tensor_bytes(out) < (uint64_t)head_dim * sizeof(float)) {
        return 0;
    }

    const NSUInteger pack_bytes = (NSUInteger)n_rows * head_dim * sizeof(float);
    if (!ds4_gpu_ensure_scratch_buffer(&g_compressor_pool_product_buffer,
                                         &g_compressor_pool_product_bytes,
                                         pack_bytes,
                                         "ds4_compressor_pool_product") ||
        !ds4_gpu_ensure_scratch_buffer(&g_compressor_pool_score_cont_buffer,
                                         &g_compressor_pool_score_cont_bytes,
                                         pack_bytes,
                                         "ds4_compressor_pool_score_cont") ||
        !ds4_gpu_ensure_scratch_buffer(&g_compressor_pool_softmax_buffer,
                                         &g_compressor_pool_softmax_bytes,
                                         pack_bytes,
                                         "ds4_compressor_pool_softmax")) {
        return 0;
    }

    const uint64_t cont_row_stride = (uint64_t)n_rows * sizeof(float);
    const uint64_t cont_plane_stride = (uint64_t)head_dim * cont_row_stride;

    /*
     * Keep the n_comp == 1 compressor path as the unfused graph sequence:
     *
     *   score = soft_max(contiguous(score))
     *   pooled = sum_rows(contiguous(kv) * score)
     *
     * The fused DS4 pool kernel is mathematically equivalent, but it reduces in
     * a different order. That is enough to create ~1e-6 compressor differences
     * and later FP8/routing flips, so this path intentionally keeps the same
     * operation boundary and memory layout as the graph.
     */
    ds4_gpu_bin_args mul_args =
        ds4_gpu_make_bin_contiguous_3d_args(n_rows, head_dim, 1);

    return
        ds4_gpu_encode_cpy_f32_f32_3d_src_strided(cb,
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Trova bug sottili e spiega quali invarianti dell'inferenza possono rompersi.

File: ds4_metal.m

```c
encode_dsv4_softmax_pool_one_comp_ggml(
        id<MTLCommandBuffer> cb,
        ds4_gpu_tensor    *out,
        id<MTLBuffer>        kvbuf,
        NSUInteger           kv_offset,
        uint64_t             kv_nb0,
        uint64_t             kv_nb1,
        uint64_t             kv_nb2,
        id<MTLBuffer>        scorebuf,
        NSUInteger           score_offset,
        uint64_t             score_nb0,
        uint64_t             score_nb1,
        uint64_t             score_nb2,
        uint32_t             n_rows,
        uint32_t             head_dim) {
    id<MTLBuffer> outbuf = ds4_gpu_tensor_buffer(out);
    if (!cb || !outbuf || !kvbuf || !scorebuf || n_rows == 0 || head_dim == 0 ||
        ds4_gpu_tensor_bytes(out) < (uint64_t)head_dim * sizeof(float)) {
        return 0;
    }

    const NSUInteger pack_bytes = (NSUInteger)n_rows * head_dim * sizeof(float);
    if (!ds4_gpu_ensure_scratch_buffer(&g_compressor_pool_product_buffer,
                                         &g_compressor_pool_product_bytes,
                                         pack_bytes,
                                         "ds4_compressor_pool_product") ||
        !ds4_gpu_ensure_scratch_buffer(&g_compressor_pool_score_cont_buffer,
                                         &g_compressor_pool_score_cont_bytes,
                                         pack_bytes,
                                         "ds4_compressor_pool_score_cont") ||
        !ds4_gpu_ensure_scratch_buffer(&g_compressor_pool_softmax_buffer,
                                         &g_compressor_pool_softmax_bytes,
                                         pack_bytes,
                                         "ds4_compressor_pool_softmax")) {
        return 0;
    }

    const uint64_t cont_row_stride = (uint64_t)n_rows * sizeof(float);
    const uint64_t cont_plane_stride = (uint64_t)head_dim * cont_row_stride;

    /*
     * Keep the n_comp == 1 compressor path as the unfused graph sequence:
     *
     *   score = soft_max(contiguous(score))
     *   pooled = sum_rows(contiguous(kv) * score)
     *
     * The fused DS4 pool kernel is mathematically equivalent, but it reduces in
     * a different order. That is enough to create ~1e-6 compressor differences
     * and later FP8/routing flips, so this path intentionally keeps the same
     * operation boundary and memory layout as the graph.
     */
    ds4_gpu_bin_args mul_args =
        ds4_gpu_make_bin_contiguous_3d_args(n_rows, head_dim, 1);

    return
        ds4_gpu_encode_cpy_f32_f32_3d_src_strided(cb,
```<｜Assistant｜></think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Trova bug sottili e spiega quali invarianti dell'inferenza possono rompersi.

File: ds4_metal.m

```c
encode_dsv4_softmax_pool_one_comp_ggml(
        id<MTLCommandBuffer> cb,
        ds4_gpu_tensor    *out,
        id<MTLBuffer>        kvbuf,
        NSUInteger           kv_offset,
        uint64_t             kv_nb0,
        uint64_t             kv_nb1,
        uint64_t             kv_nb2,
        id<MTLBuffer>        scorebuf,
        NSUInteger           score_offset,
        uint64_t             score_nb0,
        uint64_t             score_nb1,
        uint64_t             score_nb2,
        uint32_t             n_rows,
        uint32_t             head_dim) {
    id<MTLBuffer> outbuf = ds4_gpu_tensor_buffer(out);
    if (!cb || !outbuf || !kvbuf || !scorebuf || n_rows == 0 || head_dim == 0 ||
        ds4_gpu_tensor_bytes(out) < (uint64_t)head_dim * sizeof(float)) {
        return 0;
    }

    const NSUInteger pack_bytes = (NSUInteger)n_rows * head_dim * sizeof(float);
    if (!ds4_gpu_ensure_scratch_buffer(&g_compressor_pool_product_buffer,
                                         &g_compressor_pool_product_bytes,
                                         pack_bytes,
                                         "ds4_compressor_pool_product") ||
        !ds4_gpu_ensure_scratch_buffer(&g_compressor_pool_score_cont_buffer,
                                         &g_compressor_pool_score_cont_bytes,
                                         pack_bytes,
                                         "ds4_compressor_pool_score_cont") ||
        !ds4_gpu_ensure_scratch_buffer(&g_compressor_pool_softmax_buffer,
                                         &g_compressor_pool_softmax_bytes,
                                         pack_bytes,
                                         "ds4_compressor_pool_softmax")) {
        return 0;
    }

    const uint64_t cont_row_stride = (uint64_t)n_rows * sizeof(float);
    const uint64_t cont_plane_stride = (uint64_t)head_dim * cont_row_stride;

    /*
     * Keep the n_comp == 1 compressor path as the unfused graph sequence:
     *
     *   score = soft_max(contiguous(score))
     *   pooled = sum_rows(contiguous(kv) * score)
     *
     * The fused DS4 pool kernel is mathematically equivalent, but it reduces in
     * a different order. That is enough to create ~1e-6 compressor differences
     * and later FP8/routing flips, so this path intentionally keeps the same
     * operation boundary and memory layout as the graph.
     */
    ds4_gpu_bin_args mul_args =
        ds4_gpu_make_bin_contiguous_3d_args(n_rows, head_dim, 1);

    return
        ds4_gpu_encode_cpy_f32_f32_3d_src_strided(cb,
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Trova bug sottili e spiega quali invarianti dell'inferenza possono rompersi.

File: ds4_metal.m

```c
encode_dsv4_softmax_pool_one_comp_ggml(
        id<MTLCommandBuffer> cb,
        ds4_gpu_tensor    *out,
        id<MTLBuffer>        kvbuf,
        NSUInteger           kv_offset,
        uint64_t             kv_nb0,
        uint64_t             kv_nb1,
        uint64_t             kv_nb2,
        id<MTLBuffer>        scorebuf,
        NSUInteger           score_offset,
        uint64_t             score_nb0,
        uint64_t             score_nb1,
        uint64_t             score_nb2,
        uint32_t             n_rows,
        uint32_t             head_dim) {
    id<MTLBuffer> outbuf = ds4_gpu_tensor_buffer(out);
    if (!cb || !outbuf || !kvbuf || !scorebuf || n_rows == 0 || head_dim == 0 ||
        ds4_gpu_tensor_bytes(out) < (uint64_t)head_dim * sizeof(float)) {
        return 0;
    }

    const NSUInteger pack_bytes = (NSUInteger)n_rows * head_dim * sizeof(float);
    if (!ds4_gpu_ensure_scratch_buffer(&g_compressor_pool_product_buffer,
                                         &g_compressor_pool_product_bytes,
                                         pack_bytes,
                                         "ds4_compressor_pool_product") ||
        !ds4_gpu_ensure_scratch_buffer(&g_compressor_pool_score_cont_buffer,
                                         &g_compressor_pool_score_cont_bytes,
                                         pack_bytes,
                                         "ds4_compressor_pool_score_cont") ||
        !ds4_gpu_ensure_scratch_buffer(&g_compressor_pool_softmax_buffer,
                                         &g_compressor_pool_softmax_bytes,
                                         pack_bytes,
                                         "ds4_compressor_pool_softmax")) {
        return 0;
    }

    const uint64_t cont_row_stride = (uint64_t)n_rows * sizeof(float);
    const uint64_t cont_plane_stride = (uint64_t)head_dim * cont_row_stride;

    /*
     * Keep the n_comp == 1 compressor path as the unfused graph sequence:
     *
     *   score = soft_max(contiguous(score))
     *   pooled = sum_rows(contiguous(kv) * score)
     *
     * The fused DS4 pool kernel is mathematically equivalent, but it reduces in
     * a different order. That is enough to create ~1e-6 compressor differences
     * and later FP8/routing flips, so this path intentionally keeps the same
     * operation boundary and memory layout as the graph.
     */
    ds4_gpu_bin_args mul_args =
        ds4_gpu_make_bin_contiguous_3d_args(n_rows, head_dim, 1);

    return
        ds4_gpu_encode_cpy_f32_f32_3d_src_strided(cb,
```<｜Assistant｜><think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Review this excerpt for correctness risks, memory lifetime issues, and performance bottlenecks.

File: ds4_metal.m

```c
e graph.
     */
    ds4_gpu_bin_args mul_args =
        ds4_gpu_make_bin_contiguous_3d_args(n_rows, head_dim, 1);

    return
        ds4_gpu_encode_cpy_f32_f32_3d_src_strided(cb,
                                                    kvbuf,
                                                    kv_offset,
                                                    g_compressor_pool_product_buffer,
                                                    0,
                                                    n_rows,
                                                    head_dim,
                                                    1,
                                                    kv_nb0,
                                                    kv_nb1,
                                                    kv_nb2,
                                                    cont_row_stride,
                                                    cont_plane_stride) &&
        ds4_gpu_encode_cpy_f32_f32_3d_src_strided(cb,
                                                    scorebuf,
                                                    score_offset,
                                                    g_compressor_pool_score_cont_buffer,
                                                    0,
                                                    n_rows,
                                                    head_dim,
                                                    1,
                                                    score_nb0,
                                                    score_nb1,
                                                    score_nb2,
                                                    cont_row_stride,
                                                    cont_plane_stride) &&
        ds4_gpu_encode_softmax_f32_contiguous(cb,
                                                g_compressor_pool_score_cont_buffer,
                                                0,
                                                g_compressor_pool_softmax_buffer,
                                                0,
                                                n_rows,
                                                head_dim,
                                                1) &&
        ds4_gpu_encode_bin_f32_rows(cb,
                                      g_mul_pipeline,
                                      &mul_args,
                                      g_compressor_pool_product_buffer,
                                      0,
                                      g_compressor_pool_softmax_buffer,
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Review this excerpt for correctness risks, memory lifetime issues, and performance bottlenecks.

File: ds4_metal.m

```c
e graph.
     */
    ds4_gpu_bin_args mul_args =
        ds4_gpu_make_bin_contiguous_3d_args(n_rows, head_dim, 1);

    return
        ds4_gpu_encode_cpy_f32_f32_3d_src_strided(cb,
                                                    kvbuf,
                                                    kv_offset,
                                                    g_compressor_pool_product_buffer,
                                                    0,
                                                    n_rows,
                                                    head_dim,
                                                    1,
                                                    kv_nb0,
                                                    kv_nb1,
                                                    kv_nb2,
                                                    cont_row_stride,
                                                    cont_plane_stride) &&
        ds4_gpu_encode_cpy_f32_f32_3d_src_strided(cb,
                                                    scorebuf,
                                                    score_offset,
                                                    g_compressor_pool_score_cont_buffer,
                                                    0,
                                                    n_rows,
                                                    head_dim,
                                                    1,
                                                    score_nb0,
                                                    score_nb1,
                                                    score_nb2,
                                                    cont_row_stride,
                                                    cont_plane_stride) &&
        ds4_gpu_encode_softmax_f32_contiguous(cb,
                                                g_compressor_pool_score_cont_buffer,
                                                0,
                                                g_compressor_pool_softmax_buffer,
                                                0,
                                                n_rows,
                                                head_dim,
                                                1) &&
        ds4_gpu_encode_bin_f32_rows(cb,
                                      g_mul_pipeline,
                                      &mul_args,
                                      g_compressor_pool_product_buffer,
                                      0,
                                      g_compressor_pool_softmax_buffer,
```<｜Assistant｜></think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Review this excerpt for correctness risks, memory lifetime issues, and performance bottlenecks.

File: ds4_metal.m

```c
e graph.
     */
    ds4_gpu_bin_args mul_args =
        ds4_gpu_make_bin_contiguous_3d_args(n_rows, head_dim, 1);

    return
        ds4_gpu_encode_cpy_f32_f32_3d_src_strided(cb,
                                                    kvbuf,
                                                    kv_offset,
                                                    g_compressor_pool_product_buffer,
                                                    0,
                                                    n_rows,
                                                    head_dim,
                                                    1,
                                                    kv_nb0,
                                                    kv_nb1,
                                                    kv_nb2,
                                                    cont_row_stride,
                                                    cont_plane_stride) &&
        ds4_gpu_encode_cpy_f32_f32_3d_src_strided(cb,
                                                    scorebuf,
                                                    score_offset,
                                                    g_compressor_pool_score_cont_buffer,
                                                    0,
                                                    n_rows,
                                                    head_dim,
                                                    1,
                                                    score_nb0,
                                                    score_nb1,
                                                    score_nb2,
                                                    cont_row_stride,
                                                    cont_plane_stride) &&
        ds4_gpu_encode_softmax_f32_contiguous(cb,
                                                g_compressor_pool_score_cont_buffer,
                                                0,
                                                g_compressor_pool_softmax_buffer,
                                                0,
                                                n_rows,
                                                head_dim,
                                                1) &&
        ds4_gpu_encode_bin_f32_rows(cb,
                                      g_mul_pipeline,
                                      &mul_args,
                                      g_compressor_pool_product_buffer,
                                      0,
                                      g_compressor_pool_softmax_buffer,
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Review this excerpt for correctness risks, memory lifetime issues, and performance bottlenecks.

File: ds4_metal.m

```c
e graph.
     */
    ds4_gpu_bin_args mul_args =
        ds4_gpu_make_bin_contiguous_3d_args(n_rows, head_dim, 1);

    return
        ds4_gpu_encode_cpy_f32_f32_3d_src_strided(cb,
                                                    kvbuf,
                                                    kv_offset,
                                                    g_compressor_pool_product_buffer,
                                                    0,
                                                    n_rows,
                                                    head_dim,
                                                    1,
                                                    kv_nb0,
                                                    kv_nb1,
                                                    kv_nb2,
                                                    cont_row_stride,
                                                    cont_plane_stride) &&
        ds4_gpu_encode_cpy_f32_f32_3d_src_strided(cb,
                                                    scorebuf,
                                                    score_offset,
                                                    g_compressor_pool_score_cont_buffer,
                                                    0,
                                                    n_rows,
                                                    head_dim,
                                                    1,
                                                    score_nb0,
                                                    score_nb1,
                                                    score_nb2,
                                                    cont_row_stride,
                                                    cont_plane_stride) &&
        ds4_gpu_encode_softmax_f32_contiguous(cb,
                                                g_compressor_pool_score_cont_buffer,
                                                0,
                                                g_compressor_pool_softmax_buffer,
                                                0,
                                                n_rows,
                                                head_dim,
                                                1) &&
        ds4_gpu_encode_bin_f32_rows(cb,
                                      g_mul_pipeline,
                                      &mul_args,
                                      g_compressor_pool_product_buffer,
                                      0,
                                      g_compressor_pool_softmax_buffer,
```<｜Assistant｜><think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Suggest a minimal correctness-preserving optimization for this excerpt.

File: ds4_metal.m

```c
_pipeline_cache setObject:pipeline forKey:key];
    return pipeline;
}

static int ds4_gpu_disable_hot_pipeline_statics(void) {
    static int initialized;
    static int disabled;
    if (!initialized) {
        disabled = getenv("DS4_METAL_DISABLE_HOT_PIPELINE_STATICS") != NULL;
        initialized = 1;
    }
    return disabled;
}

static id<MTLComputePipelineState> ds4_gpu_hot_pipeline(
        id<MTLComputePipelineState> pipeline,
        const char *fallback_name) {
    if (!ds4_gpu_disable_hot_pipeline_statics()) return pipeline;
    return ds4_gpu_get_pipeline(fallback_name);
}

static int ds4_gpu_use_compressor_pair_nr4(void) {
    static int initialized;
    static int enabled;
    if (!initialized) {
        enabled = getenv("DS4_METAL_COMPRESSOR_PAIR_NR4") != NULL;
        initialized = 1;
    }
    return enabled;
}

static int ds4_gpu_warm_model_views(void) {
    if (g_model_view_count == 0) return 1;

    id<MTLComputePipelineState> pipeline = ds4_gpu_get_pipeline("kernel_touch_u8_stride");
    if (!pipeline) return 0;

    uint64_t stride = 1024ull * 1024ull;
    const char *stride_env = getenv("DS4_METAL_MODEL_WARMUP_STRIDE_MB");
    if (stride_env && stride_env[0]) {
        char *end = NULL;
        unsigned long long mb = strtoull(stride_env, &end, 10);
        if (end != stride_env && mb > 0 && mb <= 1024) {
            stride = mb * 1024ull * 1024ull;
        }
    }

    uint64_t total_touches = 0;
    for (uint32_t i = 0; i < g_model_view_count; i++) {
        total_touches += (g_model_views[i].bytes + stride - 1) / stride;
    }
    if (total_touches == 0 || total_touches > (uint64_t)NSUIntegerMax) return 0;

    const NSUInteger out_bytes = (NSUInteger)total_touches;
    id<MTLBuffer> out = [g_device newBufferWithLength:out_bytes
                                             options:MTLResourceStorageModeShared];
    if (!out) {
        fprintf(stderr, "ds4: Metal model warmup scratch allocation failed\n");
        return 0;
    }
    out.label = @"ds4_model_warmup";

    id<MTLCommandBuffer> cb = [g_queue commandBuffer];
    if (!cb) {
        fprintf(stderr, "ds4: Metal model warmup command buffer allocation failed\n");
        return 0;
    }

    id<MTLComputeCommandEncoder> enc = ds4_gpu_compute_encoder(cb);
    [enc setComputePipelineState:pipeline];
    uint64_t dst_offset = 0;
    for (uint32_t i = 0; i < g_model_view_count; i++) {
        const uint64_t bytes = g_model_views[i].bytes;
        const uint64_t n = (bytes + stride - 1) / stride;
        [enc setBuffer:g_model_views[i].buffer offset:0 atIndex:0];
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Suggest a minimal correctness-preserving optimization for this excerpt.

File: ds4_metal.m

```c
_pipeline_cache setObject:pipeline forKey:key];
    return pipeline;
}

static int ds4_gpu_disable_hot_pipeline_statics(void) {
    static int initialized;
    static int disabled;
    if (!initialized) {
        disabled = getenv("DS4_METAL_DISABLE_HOT_PIPELINE_STATICS") != NULL;
        initialized = 1;
    }
    return disabled;
}

static id<MTLComputePipelineState> ds4_gpu_hot_pipeline(
        id<MTLComputePipelineState> pipeline,
        const char *fallback_name) {
    if (!ds4_gpu_disable_hot_pipeline_statics()) return pipeline;
    return ds4_gpu_get_pipeline(fallback_name);
}

static int ds4_gpu_use_compressor_pair_nr4(void) {
    static int initialized;
    static int enabled;
    if (!initialized) {
        enabled = getenv("DS4_METAL_COMPRESSOR_PAIR_NR4") != NULL;
        initialized = 1;
    }
    return enabled;
}

static int ds4_gpu_warm_model_views(void) {
    if (g_model_view_count == 0) return 1;

    id<MTLComputePipelineState> pipeline = ds4_gpu_get_pipeline("kernel_touch_u8_stride");
    if (!pipeline) return 0;

    uint64_t stride = 1024ull * 1024ull;
    const char *stride_env = getenv("DS4_METAL_MODEL_WARMUP_STRIDE_MB");
    if (stride_env && stride_env[0]) {
        char *end = NULL;
        unsigned long long mb = strtoull(stride_env, &end, 10);
        if (end != stride_env && mb > 0 && mb <= 1024) {
            stride = mb * 1024ull * 1024ull;
        }
    }

    uint64_t total_touches = 0;
    for (uint32_t i = 0; i < g_model_view_count; i++) {
        total_touches += (g_model_views[i].bytes + stride - 1) / stride;
    }
    if (total_touches == 0 || total_touches > (uint64_t)NSUIntegerMax) return 0;

    const NSUInteger out_bytes = (NSUInteger)total_touches;
    id<MTLBuffer> out = [g_device newBufferWithLength:out_bytes
                                             options:MTLResourceStorageModeShared];
    if (!out) {
        fprintf(stderr, "ds4: Metal model warmup scratch allocation failed\n");
        return 0;
    }
    out.label = @"ds4_model_warmup";

    id<MTLCommandBuffer> cb = [g_queue commandBuffer];
    if (!cb) {
        fprintf(stderr, "ds4: Metal model warmup command buffer allocation failed\n");
        return 0;
    }

    id<MTLComputeCommandEncoder> enc = ds4_gpu_compute_encoder(cb);
    [enc setComputePipelineState:pipeline];
    uint64_t dst_offset = 0;
    for (uint32_t i = 0; i < g_model_view_count; i++) {
        const uint64_t bytes = g_model_views[i].bytes;
        const uint64_t n = (bytes + stride - 1) / stride;
        [enc setBuffer:g_model_views[i].buffer offset:0 atIndex:0];
```<｜Assistant｜></think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Suggest a minimal correctness-preserving optimization for this excerpt.

File: ds4_metal.m

```c
_pipeline_cache setObject:pipeline forKey:key];
    return pipeline;
}

static int ds4_gpu_disable_hot_pipeline_statics(void) {
    static int initialized;
    static int disabled;
    if (!initialized) {
        disabled = getenv("DS4_METAL_DISABLE_HOT_PIPELINE_STATICS") != NULL;
        initialized = 1;
    }
    return disabled;
}

static id<MTLComputePipelineState> ds4_gpu_hot_pipeline(
        id<MTLComputePipelineState> pipeline,
        const char *fallback_name) {
    if (!ds4_gpu_disable_hot_pipeline_statics()) return pipeline;
    return ds4_gpu_get_pipeline(fallback_name);
}

static int ds4_gpu_use_compressor_pair_nr4(void) {
    static int initialized;
    static int enabled;
    if (!initialized) {
        enabled = getenv("DS4_METAL_COMPRESSOR_PAIR_NR4") != NULL;
        initialized = 1;
    }
    return enabled;
}

static int ds4_gpu_warm_model_views(void) {
    if (g_model_view_count == 0) return 1;

    id<MTLComputePipelineState> pipeline = ds4_gpu_get_pipeline("kernel_touch_u8_stride");
    if (!pipeline) return 0;

    uint64_t stride = 1024ull * 1024ull;
    const char *stride_env = getenv("DS4_METAL_MODEL_WARMUP_STRIDE_MB");
    if (stride_env && stride_env[0]) {
        char *end = NULL;
        unsigned long long mb = strtoull(stride_env, &end, 10);
        if (end != stride_env && mb > 0 && mb <= 1024) {
            stride = mb * 1024ull * 1024ull;
        }
    }

    uint64_t total_touches = 0;
    for (uint32_t i = 0; i < g_model_view_count; i++) {
        total_touches += (g_model_views[i].bytes + stride - 1) / stride;
    }
    if (total_touches == 0 || total_touches > (uint64_t)NSUIntegerMax) return 0;

    const NSUInteger out_bytes = (NSUInteger)total_touches;
    id<MTLBuffer> out = [g_device newBufferWithLength:out_bytes
                                             options:MTLResourceStorageModeShared];
    if (!out) {
        fprintf(stderr, "ds4: Metal model warmup scratch allocation failed\n");
        return 0;
    }
    out.label = @"ds4_model_warmup";

    id<MTLCommandBuffer> cb = [g_queue commandBuffer];
    if (!cb) {
        fprintf(stderr, "ds4: Metal model warmup command buffer allocation failed\n");
        return 0;
    }

    id<MTLComputeCommandEncoder> enc = ds4_gpu_compute_encoder(cb);
    [enc setComputePipelineState:pipeline];
    uint64_t dst_offset = 0;
    for (uint32_t i = 0; i < g_model_view_count; i++) {
        const uint64_t bytes = g_model_views[i].bytes;
        const uint64_t n = (bytes + stride - 1) / stride;
        [enc setBuffer:g_model_views[i].buffer offset:0 atIndex:0];
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Suggest a minimal correctness-preserving optimization for this excerpt.

File: ds4_metal.m

```c
_pipeline_cache setObject:pipeline forKey:key];
    return pipeline;
}

static int ds4_gpu_disable_hot_pipeline_statics(void) {
    static int initialized;
    static int disabled;
    if (!initialized) {
        disabled = getenv("DS4_METAL_DISABLE_HOT_PIPELINE_STATICS") != NULL;
        initialized = 1;
    }
    return disabled;
}

static id<MTLComputePipelineState> ds4_gpu_hot_pipeline(
        id<MTLComputePipelineState> pipeline,
        const char *fallback_name) {
    if (!ds4_gpu_disable_hot_pipeline_statics()) return pipeline;
    return ds4_gpu_get_pipeline(fallback_name);
}

static int ds4_gpu_use_compressor_pair_nr4(void) {
    static int initialized;
    static int enabled;
    if (!initialized) {
        enabled = getenv("DS4_METAL_COMPRESSOR_PAIR_NR4") != NULL;
        initialized = 1;
    }
    return enabled;
}

static int ds4_gpu_warm_model_views(void) {
    if (g_model_view_count == 0) return 1;

    id<MTLComputePipelineState> pipeline = ds4_gpu_get_pipeline("kernel_touch_u8_stride");
    if (!pipeline) return 0;

    uint64_t stride = 1024ull * 1024ull;
    const char *stride_env = getenv("DS4_METAL_MODEL_WARMUP_STRIDE_MB");
    if (stride_env && stride_env[0]) {
        char *end = NULL;
        unsigned long long mb = strtoull(stride_env, &end, 10);
        if (end != stride_env && mb > 0 && mb <= 1024) {
            stride = mb * 1024ull * 1024ull;
        }
    }

    uint64_t total_touches = 0;
    for (uint32_t i = 0; i < g_model_view_count; i++) {
        total_touches += (g_model_views[i].bytes + stride - 1) / stride;
    }
    if (total_touches == 0 || total_touches > (uint64_t)NSUIntegerMax) return 0;

    const NSUInteger out_bytes = (NSUInteger)total_touches;
    id<MTLBuffer> out = [g_device newBufferWithLength:out_bytes
                                             options:MTLResourceStorageModeShared];
    if (!out) {
        fprintf(stderr, "ds4: Metal model warmup scratch allocation failed\n");
        return 0;
    }
    out.label = @"ds4_model_warmup";

    id<MTLCommandBuffer> cb = [g_queue commandBuffer];
    if (!cb) {
        fprintf(stderr, "ds4: Metal model warmup command buffer allocation failed\n");
        return 0;
    }

    id<MTLComputeCommandEncoder> enc = ds4_gpu_compute_encoder(cb);
    [enc setComputePipelineState:pipeline];
    uint64_t dst_offset = 0;
    for (uint32_t i = 0; i < g_model_view_count; i++) {
        const uint64_t bytes = g_model_views[i].bytes;
        const uint64_t n = (bytes + stride - 1) / stride;
        [enc setBuffer:g_model_views[i].buffer offset:0 atIndex:0];
```<｜Assistant｜><think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Explain what this code does and identify the inference stage it belongs to.

File: ds4_metal.m

```c
g_compressor_pool_product_buffer,
                                      0,
                                      g_compressor_pool_softmax_buffer,
                                      0,
                                      g_compressor_pool_product_buffer,
                                      0) &&
        ds4_gpu_encode_sum_rows_f32(cb,
                                      g_compressor_pool_product_buffer,
                                      0,
                                      outbuf,
                                      ds4_gpu_tensor_offset(out),
                                      n_rows,
                                      head_dim);
}

static int ds4_gpu_encode_dsv4_softmax_pool(
        id<MTLCommandBuffer> cb,
        ds4_gpu_tensor    *out,
        id<MTLBuffer>        kvbuf,
        NSUInteger           kv_offset,
        uint64_t             kv_nb0,
        uint64_t             kv_nb1,
        uint64_t             kv_nb2,
        id<MTLBuffer>        scorebuf,
        NSUInteger           score_offset,
        uint64_t             score_nb0,
        uint64_t             score_nb1,
        uint64_t             score_nb2,
        uint32_t             n_rows,
        uint32_t             head_dim,
        uint32_t             n_comp) {
    id<MTLBuffer> outbuf = ds4_gpu_tensor_buffer(out);
    if (!cb || !outbuf || !kvbuf || !scorebuf ||
        n_rows == 0 || head_dim == 0 || n_comp == 0 ||
        ds4_gpu_tensor_bytes(out) < (uint64_t)head_dim * n_comp * sizeof(float)) {
        return 0;
    }

    if (n_comp == 1) {
        return ds4_gpu_encode_dsv4_softmax_pool_one_comp_ggml(cb,
                                                                out,
                                                                kvbuf,
                                                                kv_offset,
                                                                kv_nb0,
                                                                kv_nb1,
                                                                kv_nb2,
                                                                scorebuf,
                                                                score_offset,
                                                                score_nb0,
                                                                score_nb1,
                                                                score_nb2,
                                                                n_rows,
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Explain what this code does and identify the inference stage it belongs to.

File: ds4_metal.m

```c
g_compressor_pool_product_buffer,
                                      0,
                                      g_compressor_pool_softmax_buffer,
                                      0,
                                      g_compressor_pool_product_buffer,
                                      0) &&
        ds4_gpu_encode_sum_rows_f32(cb,
                                      g_compressor_pool_product_buffer,
                                      0,
                                      outbuf,
                                      ds4_gpu_tensor_offset(out),
                                      n_rows,
                                      head_dim);
}

static int ds4_gpu_encode_dsv4_softmax_pool(
        id<MTLCommandBuffer> cb,
        ds4_gpu_tensor    *out,
        id<MTLBuffer>        kvbuf,
        NSUInteger           kv_offset,
        uint64_t             kv_nb0,
        uint64_t             kv_nb1,
        uint64_t             kv_nb2,
        id<MTLBuffer>        scorebuf,
        NSUInteger           score_offset,
        uint64_t             score_nb0,
        uint64_t             score_nb1,
        uint64_t             score_nb2,
        uint32_t             n_rows,
        uint32_t             head_dim,
        uint32_t             n_comp) {
    id<MTLBuffer> outbuf = ds4_gpu_tensor_buffer(out);
    if (!cb || !outbuf || !kvbuf || !scorebuf ||
        n_rows == 0 || head_dim == 0 || n_comp == 0 ||
        ds4_gpu_tensor_bytes(out) < (uint64_t)head_dim * n_comp * sizeof(float)) {
        return 0;
    }

    if (n_comp == 1) {
        return ds4_gpu_encode_dsv4_softmax_pool_one_comp_ggml(cb,
                                                                out,
                                                                kvbuf,
                                                                kv_offset,
                                                                kv_nb0,
                                                                kv_nb1,
                                                                kv_nb2,
                                                                scorebuf,
                                                                score_offset,
                                                                score_nb0,
                                                                score_nb1,
                                                                score_nb2,
                                                                n_rows,
```<｜Assistant｜></think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Explain what this code does and identify the inference stage it belongs to.

File: ds4_metal.m

```c
g_compressor_pool_product_buffer,
                                      0,
                                      g_compressor_pool_softmax_buffer,
                                      0,
                                      g_compressor_pool_product_buffer,
                                      0) &&
        ds4_gpu_encode_sum_rows_f32(cb,
                                      g_compressor_pool_product_buffer,
                                      0,
                                      outbuf,
                                      ds4_gpu_tensor_offset(out),
                                      n_rows,
                                      head_dim);
}

static int ds4_gpu_encode_dsv4_softmax_pool(
        id<MTLCommandBuffer> cb,
        ds4_gpu_tensor    *out,
        id<MTLBuffer>        kvbuf,
        NSUInteger           kv_offset,
        uint64_t             kv_nb0,
        uint64_t             kv_nb1,
        uint64_t             kv_nb2,
        id<MTLBuffer>        scorebuf,
        NSUInteger           score_offset,
        uint64_t             score_nb0,
        uint64_t             score_nb1,
        uint64_t             score_nb2,
        uint32_t             n_rows,
        uint32_t             head_dim,
        uint32_t             n_comp) {
    id<MTLBuffer> outbuf = ds4_gpu_tensor_buffer(out);
    if (!cb || !outbuf || !kvbuf || !scorebuf ||
        n_rows == 0 || head_dim == 0 || n_comp == 0 ||
        ds4_gpu_tensor_bytes(out) < (uint64_t)head_dim * n_comp * sizeof(float)) {
        return 0;
    }

    if (n_comp == 1) {
        return ds4_gpu_encode_dsv4_softmax_pool_one_comp_ggml(cb,
                                                                out,
                                                                kvbuf,
                                                                kv_offset,
                                                                kv_nb0,
                                                                kv_nb1,
                                                                kv_nb2,
                                                                scorebuf,
                                                                score_offset,
                                                                score_nb0,
                                                                score_nb1,
                                                                score_nb2,
                                                                n_rows,
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Explain what this code does and identify the inference stage it belongs to.

File: ds4_metal.m

```c
g_compressor_pool_product_buffer,
                                      0,
                                      g_compressor_pool_softmax_buffer,
                                      0,
                                      g_compressor_pool_product_buffer,
                                      0) &&
        ds4_gpu_encode_sum_rows_f32(cb,
                                      g_compressor_pool_product_buffer,
                                      0,
                                      outbuf,
                                      ds4_gpu_tensor_offset(out),
                                      n_rows,
                                      head_dim);
}

static int ds4_gpu_encode_dsv4_softmax_pool(
        id<MTLCommandBuffer> cb,
        ds4_gpu_tensor    *out,
        id<MTLBuffer>        kvbuf,
        NSUInteger           kv_offset,
        uint64_t             kv_nb0,
        uint64_t             kv_nb1,
        uint64_t             kv_nb2,
        id<MTLBuffer>        scorebuf,
        NSUInteger           score_offset,
        uint64_t             score_nb0,
        uint64_t             score_nb1,
        uint64_t             score_nb2,
        uint32_t             n_rows,
        uint32_t             head_dim,
        uint32_t             n_comp) {
    id<MTLBuffer> outbuf = ds4_gpu_tensor_buffer(out);
    if (!cb || !outbuf || !kvbuf || !scorebuf ||
        n_rows == 0 || head_dim == 0 || n_comp == 0 ||
        ds4_gpu_tensor_bytes(out) < (uint64_t)head_dim * n_comp * sizeof(float)) {
        return 0;
    }

    if (n_comp == 1) {
        return ds4_gpu_encode_dsv4_softmax_pool_one_comp_ggml(cb,
                                                                out,
                                                                kvbuf,
                                                                kv_offset,
                                                                kv_nb0,
                                                                kv_nb1,
                                                                kv_nb2,
                                                                scorebuf,
                                                                score_offset,
                                                                score_nb0,
                                                                score_nb1,
                                                                score_nb2,
                                                                n_rows,
```<｜Assistant｜><think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Suggest a minimal correctness-preserving optimization for this excerpt.

File: ds4_metal.m

```c
score_nb1,
                                                                score_nb2,
                                                                n_rows,
                                                                head_dim);
    }

    ds4_gpu_dsv4_softmax_pool_args args = {
        .ne00 = (int64_t)n_rows,
        .ne01 = (int64_t)head_dim,
        .ne02 = (int64_t)n_comp,
        .nb00 = kv_nb0,
        .nb01 = kv_nb1,
        .nb02 = kv_nb2,
        .nb10 = score_nb0,
        .nb11 = score_nb1,
        .nb12 = score_nb2,
        .ne0 = (int64_t)head_dim,
        .ne1 = (int64_t)n_comp,
        .nb0 = sizeof(float),
        .nb1 = (uint64_t)head_dim * sizeof(float),
    };
    const uint64_t n = (uint64_t)head_dim * n_comp;

    id<MTLComputeCommandEncoder> enc = ds4_gpu_compute_encoder(cb);
    [enc setComputePipelineState:g_dsv4_softmax_pool_pipeline];
    [enc setBytes:&args length:sizeof(args) atIndex:0];
    [enc setBuffer:kvbuf offset:kv_offset atIndex:1];
    [enc setBuffer:scorebuf offset:score_offset atIndex:2];
    [enc setBuffer:outbuf offset:ds4_gpu_tensor_offset(out) atIndex:3];
    [enc dispatchThreadgroups:MTLSizeMake(((NSUInteger)n + 255u) / 256u, 1, 1)
         threadsPerThreadgroup:MTLSizeMake(256, 1, 1)];
    ds4_gpu_end_compute_encoder(cb, enc);
    return 1;
}

static int ds4_gpu_encode_concat_f32_dim1(
        id<MTLCommandBuffer> cb,
        id<MTLBuffer>        src0,
        NSUInteger           src0_offset,
        uint32_t             src0_rows,
        uint64_t             src0_row_stride,
        id<MTLBuffer>        src1,
        NSUInteger           src1_offset,
        uint32_t             src1_rows,
        uint64_t             src1_row_stride,
        id<MTLBuffer>        dst,
        NSUInteger           dst_offset,
        uint32_t             cols,
        uint64_t             dst_row_stride) {
    if (!cb || !src0 || !src1 || !dst || cols == 0 || src0_rows == 0 || src1_rows == 0) {
        return 0;
    }

    const uint32_t rows = src0_rows + src1_rows;
    const uint64_t src0_plane = (uint64_t)src0_rows * src0_row_stride;
    const uint64_t src1_plane = (uint64_t)src1_rows * src1_row_stride;
    const uint64_t dst_plane = (uint64_t)rows * dst_row_stride;
    ds4_gpu_concat_args args = {
        .ne00 = (int32_t)cols,
        .ne01 = (int32_t)src0_rows,
        .ne02 = 1,
        .ne03 = 1,
        .nb00 = sizeof(float),
        .nb01 = src0_row_stride,
        .nb02 = src0_plane,
        .nb03 = src0_plane,
        .ne10 = (int32_t)cols,
        .ne11 = (int32_t)src1_rows,
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Suggest a minimal correctness-preserving optimization for this excerpt.

File: ds4_metal.m

```c
score_nb1,
                                                                score_nb2,
                                                                n_rows,
                                                                head_dim);
    }

    ds4_gpu_dsv4_softmax_pool_args args = {
        .ne00 = (int64_t)n_rows,
        .ne01 = (int64_t)head_dim,
        .ne02 = (int64_t)n_comp,
        .nb00 = kv_nb0,
        .nb01 = kv_nb1,
        .nb02 = kv_nb2,
        .nb10 = score_nb0,
        .nb11 = score_nb1,
        .nb12 = score_nb2,
        .ne0 = (int64_t)head_dim,
        .ne1 = (int64_t)n_comp,
        .nb0 = sizeof(float),
        .nb1 = (uint64_t)head_dim * sizeof(float),
    };
    const uint64_t n = (uint64_t)head_dim * n_comp;

    id<MTLComputeCommandEncoder> enc = ds4_gpu_compute_encoder(cb);
    [enc setComputePipelineState:g_dsv4_softmax_pool_pipeline];
    [enc setBytes:&args length:sizeof(args) atIndex:0];
    [enc setBuffer:kvbuf offset:kv_offset atIndex:1];
    [enc setBuffer:scorebuf offset:score_offset atIndex:2];
    [enc setBuffer:outbuf offset:ds4_gpu_tensor_offset(out) atIndex:3];
    [enc dispatchThreadgroups:MTLSizeMake(((NSUInteger)n + 255u) / 256u, 1, 1)
         threadsPerThreadgroup:MTLSizeMake(256, 1, 1)];
    ds4_gpu_end_compute_encoder(cb, enc);
    return 1;
}

static int ds4_gpu_encode_concat_f32_dim1(
        id<MTLCommandBuffer> cb,
        id<MTLBuffer>        src0,
        NSUInteger           src0_offset,
        uint32_t             src0_rows,
        uint64_t             src0_row_stride,
        id<MTLBuffer>        src1,
        NSUInteger           src1_offset,
        uint32_t             src1_rows,
        uint64_t             src1_row_stride,
        id<MTLBuffer>        dst,
        NSUInteger           dst_offset,
        uint32_t             cols,
        uint64_t             dst_row_stride) {
    if (!cb || !src0 || !src1 || !dst || cols == 0 || src0_rows == 0 || src1_rows == 0) {
        return 0;
    }

    const uint32_t rows = src0_rows + src1_rows;
    const uint64_t src0_plane = (uint64_t)src0_rows * src0_row_stride;
    const uint64_t src1_plane = (uint64_t)src1_rows * src1_row_stride;
    const uint64_t dst_plane = (uint64_t)rows * dst_row_stride;
    ds4_gpu_concat_args args = {
        .ne00 = (int32_t)cols,
        .ne01 = (int32_t)src0_rows,
        .ne02 = 1,
        .ne03 = 1,
        .nb00 = sizeof(float),
        .nb01 = src0_row_stride,
        .nb02 = src0_plane,
        .nb03 = src0_plane,
        .ne10 = (int32_t)cols,
        .ne11 = (int32_t)src1_rows,
```<｜Assistant｜></think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Suggest a minimal correctness-preserving optimization for this excerpt.

File: ds4_metal.m

```c
score_nb1,
                                                                score_nb2,
                                                                n_rows,
                                                                head_dim);
    }

    ds4_gpu_dsv4_softmax_pool_args args = {
        .ne00 = (int64_t)n_rows,
        .ne01 = (int64_t)head_dim,
        .ne02 = (int64_t)n_comp,
        .nb00 = kv_nb0,
        .nb01 = kv_nb1,
        .nb02 = kv_nb2,
        .nb10 = score_nb0,
        .nb11 = score_nb1,
        .nb12 = score_nb2,
        .ne0 = (int64_t)head_dim,
        .ne1 = (int64_t)n_comp,
        .nb0 = sizeof(float),
        .nb1 = (uint64_t)head_dim * sizeof(float),
    };
    const uint64_t n = (uint64_t)head_dim * n_comp;

    id<MTLComputeCommandEncoder> enc = ds4_gpu_compute_encoder(cb);
    [enc setComputePipelineState:g_dsv4_softmax_pool_pipeline];
    [enc setBytes:&args length:sizeof(args) atIndex:0];
    [enc setBuffer:kvbuf offset:kv_offset atIndex:1];
    [enc setBuffer:scorebuf offset:score_offset atIndex:2];
    [enc setBuffer:outbuf offset:ds4_gpu_tensor_offset(out) atIndex:3];
    [enc dispatchThreadgroups:MTLSizeMake(((NSUInteger)n + 255u) / 256u, 1, 1)
         threadsPerThreadgroup:MTLSizeMake(256, 1, 1)];
    ds4_gpu_end_compute_encoder(cb, enc);
    return 1;
}

static int ds4_gpu_encode_concat_f32_dim1(
        id<MTLCommandBuffer> cb,
        id<MTLBuffer>        src0,
        NSUInteger           src0_offset,
        uint32_t             src0_rows,
        uint64_t             src0_row_stride,
        id<MTLBuffer>        src1,
        NSUInteger           src1_offset,
        uint32_t             src1_rows,
        uint64_t             src1_row_stride,
        id<MTLBuffer>        dst,
        NSUInteger           dst_offset,
        uint32_t             cols,
        uint64_t             dst_row_stride) {
    if (!cb || !src0 || !src1 || !dst || cols == 0 || src0_rows == 0 || src1_rows == 0) {
        return 0;
    }

    const uint32_t rows = src0_rows + src1_rows;
    const uint64_t src0_plane = (uint64_t)src0_rows * src0_row_stride;
    const uint64_t src1_plane = (uint64_t)src1_rows * src1_row_stride;
    const uint64_t dst_plane = (uint64_t)rows * dst_row_stride;
    ds4_gpu_concat_args args = {
        .ne00 = (int32_t)cols,
        .ne01 = (int32_t)src0_rows,
        .ne02 = 1,
        .ne03 = 1,
        .nb00 = sizeof(float),
        .nb01 = src0_row_stride,
        .nb02 = src0_plane,
        .nb03 = src0_plane,
        .ne10 = (int32_t)cols,
        .ne11 = (int32_t)src1_rows,
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Suggest a minimal correctness-preserving optimization for this excerpt.

File: ds4_metal.m

```c
score_nb1,
                                                                score_nb2,
                                                                n_rows,
                                                                head_dim);
    }

    ds4_gpu_dsv4_softmax_pool_args args = {
        .ne00 = (int64_t)n_rows,
        .ne01 = (int64_t)head_dim,
        .ne02 = (int64_t)n_comp,
        .nb00 = kv_nb0,
        .nb01 = kv_nb1,
        .nb02 = kv_nb2,
        .nb10 = score_nb0,
        .nb11 = score_nb1,
        .nb12 = score_nb2,
        .ne0 = (int64_t)head_dim,
        .ne1 = (int64_t)n_comp,
        .nb0 = sizeof(float),
        .nb1 = (uint64_t)head_dim * sizeof(float),
    };
    const uint64_t n = (uint64_t)head_dim * n_comp;

    id<MTLComputeCommandEncoder> enc = ds4_gpu_compute_encoder(cb);
    [enc setComputePipelineState:g_dsv4_softmax_pool_pipeline];
    [enc setBytes:&args length:sizeof(args) atIndex:0];
    [enc setBuffer:kvbuf offset:kv_offset atIndex:1];
    [enc setBuffer:scorebuf offset:score_offset atIndex:2];
    [enc setBuffer:outbuf offset:ds4_gpu_tensor_offset(out) atIndex:3];
    [enc dispatchThreadgroups:MTLSizeMake(((NSUInteger)n + 255u) / 256u, 1, 1)
         threadsPerThreadgroup:MTLSizeMake(256, 1, 1)];
    ds4_gpu_end_compute_encoder(cb, enc);
    return 1;
}

static int ds4_gpu_encode_concat_f32_dim1(
        id<MTLCommandBuffer> cb,
        id<MTLBuffer>        src0,
        NSUInteger           src0_offset,
        uint32_t             src0_rows,
        uint64_t             src0_row_stride,
        id<MTLBuffer>        src1,
        NSUInteger           src1_offset,
        uint32_t             src1_rows,
        uint64_t             src1_row_stride,
        id<MTLBuffer>        dst,
        NSUInteger           dst_offset,
        uint32_t             cols,
        uint64_t             dst_row_stride) {
    if (!cb || !src0 || !src1 || !dst || cols == 0 || src0_rows == 0 || src1_rows == 0) {
        return 0;
    }

    const uint32_t rows = src0_rows + src1_rows;
    const uint64_t src0_plane = (uint64_t)src0_rows * src0_row_stride;
    const uint64_t src1_plane = (uint64_t)src1_rows * src1_row_stride;
    const uint64_t dst_plane = (uint64_t)rows * dst_row_stride;
    ds4_gpu_concat_args args = {
        .ne00 = (int32_t)cols,
        .ne01 = (int32_t)src0_rows,
        .ne02 = 1,
        .ne03 = 1,
        .nb00 = sizeof(float),
        .nb01 = src0_row_stride,
        .nb02 = src0_plane,
        .nb03 = src0_plane,
        .ne10 = (int32_t)cols,
        .ne11 = (int32_t)src1_rows,
```<｜Assistant｜><think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Trova bug sottili e spiega quali invarianti dell'inferenza possono rompersi.

File: ds4_metal.m

```c
.nb00 = sizeof(float),
        .nb01 = src0_row_stride,
        .nb02 = src0_plane,
        .nb03 = src0_plane,
        .ne10 = (int32_t)cols,
        .ne11 = (int32_t)src1_rows,
        .ne12 = 1,
        .ne13 = 1,
        .nb10 = sizeof(float),
        .nb11 = src1_row_stride,
        .nb12 = src1_plane,
        .nb13 = src1_plane,
        .ne0 = (int32_t)cols,
        .ne1 = (int32_t)rows,
        .ne2 = 1,
        .ne3 = 1,
        .nb0 = sizeof(float),
        .nb1 = dst_row_stride,
        .nb2 = dst_plane,
        .nb3 = dst_plane,
        .dim = 1,
    };

    NSUInteger nth = cols < 1024u ? (NSUInteger)cols : 1024u;
    const NSUInteger max_threads = g_concat_pipeline.maxTotalThreadsPerThreadgroup;
    if (nth > max_threads) nth = max_threads;
    if (nth == 0) nth = 1;

    id<MTLComputeCommandEncoder> enc = ds4_gpu_compute_encoder(cb);
    [enc setComputePipelineState:g_concat_pipeline];
    [enc setBytes:&args length:sizeof(args) atIndex:0];
    [enc setBuffer:src0 offset:src0_offset atIndex:1];
    [enc setBuffer:src1 offset:src1_offset atIndex:2];
    [enc setBuffer:dst offset:dst_offset atIndex:3];
    [enc dispatchThreadgroups:MTLSizeMake(rows, 1, 1)
         threadsPerThreadgroup:MTLSizeMake(nth, 1, 1)];
    ds4_gpu_end_compute_encoder(cb, enc);
    return 1;
}

static int ds4_gpu_encode_compressor_pool(
        id<MTLCommandBuffer>   cb,
        ds4_gpu_tensor      *out,
        const ds4_gpu_tensor *state_kv,
        const ds4_gpu_tensor *state_score,
        uint32_t               head_dim,
        uint32_t               ratio) {
    id<MTLBuffer> statekvbuf = ds4_gpu_tensor_buffer(state_kv);
    id<MTLBuffer> statescbuf = ds4_gpu_tensor_buffer(state_score);
    if (!cb || !out || !statekvbuf || !statescbuf || head_dim == 0 || ratio == 0) return 0;

    const uint32_t coff = ratio == 4u ? 2u : 1u;
    const uint32_t width = coff * head_dim;
    const uint32_t rows = coff * ratio;
    const uint64_t state_bytes = (uint64_t)width * rows * sizeof(float);
    if (ds4_gpu_tensor_bytes(state_kv) < state_bytes ||
        ds4_gpu_tensor_bytes(state_score) < state_bytes) {
        return 0;
    }

    if (ratio != 4u) {
        const uint64_t row_stride = (uint64_t)width * sizeof(float);
        return ds4_gpu_encode_dsv4_softmax_pool(cb,
                                                  out,
                                                  statekvbuf,
                                                  ds4_gpu_tensor_offset(state_kv),
                                                  row_stride,
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Trova bug sottili e spiega quali invarianti dell'inferenza possono rompersi.

File: ds4_metal.m

```c
.nb00 = sizeof(float),
        .nb01 = src0_row_stride,
        .nb02 = src0_plane,
        .nb03 = src0_plane,
        .ne10 = (int32_t)cols,
        .ne11 = (int32_t)src1_rows,
        .ne12 = 1,
        .ne13 = 1,
        .nb10 = sizeof(float),
        .nb11 = src1_row_stride,
        .nb12 = src1_plane,
        .nb13 = src1_plane,
        .ne0 = (int32_t)cols,
        .ne1 = (int32_t)rows,
        .ne2 = 1,
        .ne3 = 1,
        .nb0 = sizeof(float),
        .nb1 = dst_row_stride,
        .nb2 = dst_plane,
        .nb3 = dst_plane,
        .dim = 1,
    };

    NSUInteger nth = cols < 1024u ? (NSUInteger)cols : 1024u;
    const NSUInteger max_threads = g_concat_pipeline.maxTotalThreadsPerThreadgroup;
    if (nth > max_threads) nth = max_threads;
    if (nth == 0) nth = 1;

    id<MTLComputeCommandEncoder> enc = ds4_gpu_compute_encoder(cb);
    [enc setComputePipelineState:g_concat_pipeline];
    [enc setBytes:&args length:sizeof(args) atIndex:0];
    [enc setBuffer:src0 offset:src0_offset atIndex:1];
    [enc setBuffer:src1 offset:src1_offset atIndex:2];
    [enc setBuffer:dst offset:dst_offset atIndex:3];
    [enc dispatchThreadgroups:MTLSizeMake(rows, 1, 1)
         threadsPerThreadgroup:MTLSizeMake(nth, 1, 1)];
    ds4_gpu_end_compute_encoder(cb, enc);
    return 1;
}

static int ds4_gpu_encode_compressor_pool(
        id<MTLCommandBuffer>   cb,
        ds4_gpu_tensor      *out,
        const ds4_gpu_tensor *state_kv,
        const ds4_gpu_tensor *state_score,
        uint32_t               head_dim,
        uint32_t               ratio) {
    id<MTLBuffer> statekvbuf = ds4_gpu_tensor_buffer(state_kv);
    id<MTLBuffer> statescbuf = ds4_gpu_tensor_buffer(state_score);
    if (!cb || !out || !statekvbuf || !statescbuf || head_dim == 0 || ratio == 0) return 0;

    const uint32_t coff = ratio == 4u ? 2u : 1u;
    const uint32_t width = coff * head_dim;
    const uint32_t rows = coff * ratio;
    const uint64_t state_bytes = (uint64_t)width * rows * sizeof(float);
    if (ds4_gpu_tensor_bytes(state_kv) < state_bytes ||
        ds4_gpu_tensor_bytes(state_score) < state_bytes) {
        return 0;
    }

    if (ratio != 4u) {
        const uint64_t row_stride = (uint64_t)width * sizeof(float);
        return ds4_gpu_encode_dsv4_softmax_pool(cb,
                                                  out,
                                                  statekvbuf,
                                                  ds4_gpu_tensor_offset(state_kv),
                                                  row_stride,
```<｜Assistant｜></think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Trova bug sottili e spiega quali invarianti dell'inferenza possono rompersi.

File: ds4_metal.m

```c
.nb00 = sizeof(float),
        .nb01 = src0_row_stride,
        .nb02 = src0_plane,
        .nb03 = src0_plane,
        .ne10 = (int32_t)cols,
        .ne11 = (int32_t)src1_rows,
        .ne12 = 1,
        .ne13 = 1,
        .nb10 = sizeof(float),
        .nb11 = src1_row_stride,
        .nb12 = src1_plane,
        .nb13 = src1_plane,
        .ne0 = (int32_t)cols,
        .ne1 = (int32_t)rows,
        .ne2 = 1,
        .ne3 = 1,
        .nb0 = sizeof(float),
        .nb1 = dst_row_stride,
        .nb2 = dst_plane,
        .nb3 = dst_plane,
        .dim = 1,
    };

    NSUInteger nth = cols < 1024u ? (NSUInteger)cols : 1024u;
    const NSUInteger max_threads = g_concat_pipeline.maxTotalThreadsPerThreadgroup;
    if (nth > max_threads) nth = max_threads;
    if (nth == 0) nth = 1;

    id<MTLComputeCommandEncoder> enc = ds4_gpu_compute_encoder(cb);
    [enc setComputePipelineState:g_concat_pipeline];
    [enc setBytes:&args length:sizeof(args) atIndex:0];
    [enc setBuffer:src0 offset:src0_offset atIndex:1];
    [enc setBuffer:src1 offset:src1_offset atIndex:2];
    [enc setBuffer:dst offset:dst_offset atIndex:3];
    [enc dispatchThreadgroups:MTLSizeMake(rows, 1, 1)
         threadsPerThreadgroup:MTLSizeMake(nth, 1, 1)];
    ds4_gpu_end_compute_encoder(cb, enc);
    return 1;
}

static int ds4_gpu_encode_compressor_pool(
        id<MTLCommandBuffer>   cb,
        ds4_gpu_tensor      *out,
        const ds4_gpu_tensor *state_kv,
        const ds4_gpu_tensor *state_score,
        uint32_t               head_dim,
        uint32_t               ratio) {
    id<MTLBuffer> statekvbuf = ds4_gpu_tensor_buffer(state_kv);
    id<MTLBuffer> statescbuf = ds4_gpu_tensor_buffer(state_score);
    if (!cb || !out || !statekvbuf || !statescbuf || head_dim == 0 || ratio == 0) return 0;

    const uint32_t coff = ratio == 4u ? 2u : 1u;
    const uint32_t width = coff * head_dim;
    const uint32_t rows = coff * ratio;
    const uint64_t state_bytes = (uint64_t)width * rows * sizeof(float);
    if (ds4_gpu_tensor_bytes(state_kv) < state_bytes ||
        ds4_gpu_tensor_bytes(state_score) < state_bytes) {
        return 0;
    }

    if (ratio != 4u) {
        const uint64_t row_stride = (uint64_t)width * sizeof(float);
        return ds4_gpu_encode_dsv4_softmax_pool(cb,
                                                  out,
                                                  statekvbuf,
                                                  ds4_gpu_tensor_offset(state_kv),
                                                  row_stride,
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Trova bug sottili e spiega quali invarianti dell'inferenza possono rompersi.

File: ds4_metal.m

```c
.nb00 = sizeof(float),
        .nb01 = src0_row_stride,
        .nb02 = src0_plane,
        .nb03 = src0_plane,
        .ne10 = (int32_t)cols,
        .ne11 = (int32_t)src1_rows,
        .ne12 = 1,
        .ne13 = 1,
        .nb10 = sizeof(float),
        .nb11 = src1_row_stride,
        .nb12 = src1_plane,
        .nb13 = src1_plane,
        .ne0 = (int32_t)cols,
        .ne1 = (int32_t)rows,
        .ne2 = 1,
        .ne3 = 1,
        .nb0 = sizeof(float),
        .nb1 = dst_row_stride,
        .nb2 = dst_plane,
        .nb3 = dst_plane,
        .dim = 1,
    };

    NSUInteger nth = cols < 1024u ? (NSUInteger)cols : 1024u;
    const NSUInteger max_threads = g_concat_pipeline.maxTotalThreadsPerThreadgroup;
    if (nth > max_threads) nth = max_threads;
    if (nth == 0) nth = 1;

    id<MTLComputeCommandEncoder> enc = ds4_gpu_compute_encoder(cb);
    [enc setComputePipelineState:g_concat_pipeline];
    [enc setBytes:&args length:sizeof(args) atIndex:0];
    [enc setBuffer:src0 offset:src0_offset atIndex:1];
    [enc setBuffer:src1 offset:src1_offset atIndex:2];
    [enc setBuffer:dst offset:dst_offset atIndex:3];
    [enc dispatchThreadgroups:MTLSizeMake(rows, 1, 1)
         threadsPerThreadgroup:MTLSizeMake(nth, 1, 1)];
    ds4_gpu_end_compute_encoder(cb, enc);
    return 1;
}

static int ds4_gpu_encode_compressor_pool(
        id<MTLCommandBuffer>   cb,
        ds4_gpu_tensor      *out,
        const ds4_gpu_tensor *state_kv,
        const ds4_gpu_tensor *state_score,
        uint32_t               head_dim,
        uint32_t               ratio) {
    id<MTLBuffer> statekvbuf = ds4_gpu_tensor_buffer(state_kv);
    id<MTLBuffer> statescbuf = ds4_gpu_tensor_buffer(state_score);
    if (!cb || !out || !statekvbuf || !statescbuf || head_dim == 0 || ratio == 0) return 0;

    const uint32_t coff = ratio == 4u ? 2u : 1u;
    const uint32_t width = coff * head_dim;
    const uint32_t rows = coff * ratio;
    const uint64_t state_bytes = (uint64_t)width * rows * sizeof(float);
    if (ds4_gpu_tensor_bytes(state_kv) < state_bytes ||
        ds4_gpu_tensor_bytes(state_score) < state_bytes) {
        return 0;
    }

    if (ratio != 4u) {
        const uint64_t row_stride = (uint64_t)width * sizeof(float);
        return ds4_gpu_encode_dsv4_softmax_pool(cb,
                                                  out,
                                                  statekvbuf,
                                                  ds4_gpu_tensor_offset(state_kv),
                                                  row_stride,
```<｜Assistant｜><think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Review this excerpt for correctness risks, memory lifetime issues, and performance bottlenecks.

File: ds4_metal.m

```c
statekvbuf,
                                                  ds4_gpu_tensor_offset(state_kv),
                                                  row_stride,
                                                  sizeof(float),
                                                  (uint64_t)rows * row_stride,
                                                  statescbuf,
                                                  ds4_gpu_tensor_offset(state_score),
                                                  row_stride,
                                                  sizeof(float),
                                                  (uint64_t)rows * row_stride,
                                                  ratio,
                                                  head_dim,
                                                  1);
    }

    const NSUInteger packed_bytes = (NSUInteger)8u * head_dim * sizeof(float);
    if (!ds4_gpu_ensure_scratch_buffer(&g_compressor_pool_kv_buffer,
                                         &g_compressor_pool_kv_bytes,
                                         packed_bytes,
                                         "ds4_compressor_pool_kv") ||
        !ds4_gpu_ensure_scratch_buffer(&g_compressor_pool_score_buffer,
                                         &g_compressor_pool_score_bytes,
                                         packed_bytes,
                                         "ds4_compressor_pool_score")) {
        return 0;
    }

    const uint64_t state_row_stride = (uint64_t)width * sizeof(float);
    const uint64_t pool_row_stride = (uint64_t)head_dim * sizeof(float);
    const NSUInteger curr_offset = (NSUInteger)4u * state_row_stride +
                                   (NSUInteger)head_dim * sizeof(float);
    if (!ds4_gpu_encode_concat_f32_dim1(cb,
                                          statekvbuf,
                                          ds4_gpu_tensor_offset(state_kv),
                                          4,
                                          state_row_stride,
                                          statekvbuf,
                                          ds4_gpu_tensor_offset(state_kv) + curr_offset,
                                          4,
                                          state_row_stride,
                                          g_compressor_pool_kv_buffer,
                                          0,
                                          head_dim,
                                          pool_row_stride) ||
        !ds4_gpu_encode_concat_f32_dim1(cb,
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Review this excerpt for correctness risks, memory lifetime issues, and performance bottlenecks.

File: ds4_metal.m

```c
statekvbuf,
                                                  ds4_gpu_tensor_offset(state_kv),
                                                  row_stride,
                                                  sizeof(float),
                                                  (uint64_t)rows * row_stride,
                                                  statescbuf,
                                                  ds4_gpu_tensor_offset(state_score),
                                                  row_stride,
                                                  sizeof(float),
                                                  (uint64_t)rows * row_stride,
                                                  ratio,
                                                  head_dim,
                                                  1);
    }

    const NSUInteger packed_bytes = (NSUInteger)8u * head_dim * sizeof(float);
    if (!ds4_gpu_ensure_scratch_buffer(&g_compressor_pool_kv_buffer,
                                         &g_compressor_pool_kv_bytes,
                                         packed_bytes,
                                         "ds4_compressor_pool_kv") ||
        !ds4_gpu_ensure_scratch_buffer(&g_compressor_pool_score_buffer,
                                         &g_compressor_pool_score_bytes,
                                         packed_bytes,
                                         "ds4_compressor_pool_score")) {
        return 0;
    }

    const uint64_t state_row_stride = (uint64_t)width * sizeof(float);
    const uint64_t pool_row_stride = (uint64_t)head_dim * sizeof(float);
    const NSUInteger curr_offset = (NSUInteger)4u * state_row_stride +
                                   (NSUInteger)head_dim * sizeof(float);
    if (!ds4_gpu_encode_concat_f32_dim1(cb,
                                          statekvbuf,
                                          ds4_gpu_tensor_offset(state_kv),
                                          4,
                                          state_row_stride,
                                          statekvbuf,
                                          ds4_gpu_tensor_offset(state_kv) + curr_offset,
                                          4,
                                          state_row_stride,
                                          g_compressor_pool_kv_buffer,
                                          0,
                                          head_dim,
                                          pool_row_stride) ||
        !ds4_gpu_encode_concat_f32_dim1(cb,
```<｜Assistant｜></think>


[System] You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.

[User]
Review this excerpt for correctness risks, memory lifetime issues, and performance bottlenecks.

File: ds4_metal.m

```c
statekvbuf,
                                                  ds4_gpu_tensor_offset(state_kv),
                                                  row_stride,
                                                  sizeof(float),
                                                  (uint64_t)rows * row_stride,
                                                  statescbuf,
                                                  ds4_gpu_tensor_offset(state_score),
                                                  row_stride,
                                                  sizeof(float),
                                                  (uint64_t)rows * row_stride,
                                                  ratio,
                                                  head_dim,
                                                  1);
    }

    const NSUInteger packed_bytes = (NSUInteger)8u * head_dim * sizeof(float);
    if (!ds4_gpu_ensure_scratch_buffer(&g_compressor_pool_kv_buffer,
                                         &g_compressor_pool_kv_bytes,
                                         packed_bytes,
                                         "ds4_compressor_pool_kv") ||
        !ds4_gpu_ensure_scratch_buffer(&g_compressor_pool_score_buffer,
                                         &g_compressor_pool_score_bytes,
                                         packed_bytes,
                                         "ds4_compressor_pool_score")) {
        return 0;
    }

    const uint64_t state_row_stride = (uint64_t)width * sizeof(float);
    const uint64_t pool_row_stride = (uint64_t)head_dim * sizeof(float);
    const NSUInteger curr_offset = (NSUInteger)4u * state_row_stride +
                                   (NSUInteger)head_dim * sizeof(float);
    if (!ds4_gpu_encode_concat_f32_dim1(cb,
                                          statekvbuf,
                                          ds4_gpu_tensor_offset(state_kv),
                                          4,
                                          state_row_stride,
                                          statekvbuf,
                                          ds4_gpu_tensor_offset(state_kv) + curr_offset,
                                          4,
                                          state_row_stride,
                                          g_compressor_pool_kv_buffer,
                                          0,
                                          head_dim,
                                          pool_row_stride) ||
        !ds4_gpu_encode_concat_f32_dim1(cb,
```

<｜begin▁of▁sentence｜>You are DeepSeek V4 Flash running locally. Answer accurately, preserve technical details, and use tools only when the prompt asks for tool use.<｜User｜>Review this excerpt for correctness risks, memory lifetime issues, and performance bottlenecks.

File: ds4_metal.m

```c
statekvbuf,
                                                  ds4_gpu_tensor_offset(state_kv),
                                                  row_stride,
                                                  sizeof(float),
                                                  (uint64_t)rows * row_stride,
                                                  statescbuf,
                                                  ds4_gpu_tensor_offset(state_score),
                                                  row_stride,
                                                  sizeof(float),
                                                  (uint64_t)rows * row_stride,
                                                  ratio,
                                                  head_dim,
                                                  1);
    }

    const NSUInteger packed_bytes = (NSUInteger)8u * head_dim * sizeof(float);
    if (!ds4_gpu_ensure_scratch_buffer(&g_compressor_pool_kv_buffer,
                                         &g_compressor_pool_kv_bytes,
                                         packed_bytes,
                                         "ds4_compressor_pool_kv") ||
        !ds4_gpu_ensure_scratch_buffer(&g_compressor_pool_score_buffer,
                                         &g_compressor_pool_score_bytes,
                                         packed_bytes,
                                         "ds4_compressor_pool_score")) {
        return 0;
    }

    const uint64_t state_row_stride = (uint64_t)width * sizeof(float);
    const uint64_t pool_row_stride = (uint64_t)head_dim * sizeof(float);
    const NSUInteger curr_offset = (NSUInteger)4u * state_row_stride +
                                   (NSUInteger)head_dim * sizeof(float);
    if (!ds4_gpu_encode_concat_f32_dim1(cb,
                                          statekvbuf,
                                          ds4_gpu_tensor_offset(state_kv),
                                          4,
                                          state_row_stride,
                                          statekvbuf,
                                          ds4_gpu_tensor_offset(state_kv) + curr_offset,
                                          4,
                                          state_row_stride,
                                          g_compressor_pool_kv_buffer,
                                          0,
                                          head_dim,
                                          pool_row_stride) ||
        !ds4_gpu_encode_concat_f32_dim1(cb,
```<｜Assistant｜><think>