[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.c

```c
tn_factor,
                                                            DS4_ROPE_YARN_BETA_FAST,
                                                            DS4_ROPE_YARN_BETA_SLOW,
                                                            DS4_RMS_EPS) != 0;
                    if (ok && emit) {
                        ds4_gpu_tensor *comp_row_view = ds4_gpu_tensor_view(
                                g->layer_attn_comp_cache[il],
                                (uint64_t)comp_row * DS4_N_HEAD_DIM * sizeof(float),
                                (uint64_t)DS4_N_HEAD_DIM * sizeof(float));
                        ok = comp_row_view &&
                             ds4_gpu_dsv4_fp8_kv_quantize_tensor(comp_row_view,
                                                                   1,
                                                                   DS4_N_HEAD_DIM,
                                                                   DS4_N_ROT) != 0;
                        if (ok) {
                            metal_graph_debug_dump_tensor("KVcompress",
                                                          comp_row_view,
                                                          DS4_N_HEAD_DIM,
                                                          il,
                                                          pos);
                        }
                        ds4_gpu_tensor_free(comp_row_view);
                    }
                    if (ok && emit) g->layer_n_comp[il]++;
                    if (comp_counts) comp_counts[t] = g->layer_n_comp[il];
                    if (ok && t == 0) ok = metal_graph_capture_prefix1_attn_state(g, il);
                    ds4_gpu_tensor_free(sc_view);
                    ds4_gpu_tensor_free(kv_view);
                }
            }
            n_comp = g->layer_n_comp[il];
        }
        DS4_METAL_PROFILE_ATTN_STAGE("compressor");

        if (ok && ratio == 4) {
            const uint32_t index_width = coff * DS4_N_INDEXER_HEAD_DIM;
            if (!layer->indexer_compressor_kv || !layer->indexer_compressor_gate ||
                !layer->indexer_compressor_ape || !layer->indexer_compressor_norm ||
                !layer->indexer_attn_q_b || !layer->indexer_proj) {
                fprintf(stderr, "ds4: Metal layer-major prefill needs indexer weights\n");
                ok = false;
            }
            if (ok) ok = ds4_gpu_matmul_f16_tensor(g->batch_comp_kv,
                                                     model->map,
                                                     model->size,
```

<｜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.c

```c
tn_factor,
                                                            DS4_ROPE_YARN_BETA_FAST,
                                                            DS4_ROPE_YARN_BETA_SLOW,
                                                            DS4_RMS_EPS) != 0;
                    if (ok && emit) {
                        ds4_gpu_tensor *comp_row_view = ds4_gpu_tensor_view(
                                g->layer_attn_comp_cache[il],
                                (uint64_t)comp_row * DS4_N_HEAD_DIM * sizeof(float),
                                (uint64_t)DS4_N_HEAD_DIM * sizeof(float));
                        ok = comp_row_view &&
                             ds4_gpu_dsv4_fp8_kv_quantize_tensor(comp_row_view,
                                                                   1,
                                                                   DS4_N_HEAD_DIM,
                                                                   DS4_N_ROT) != 0;
                        if (ok) {
                            metal_graph_debug_dump_tensor("KVcompress",
                                                          comp_row_view,
                                                          DS4_N_HEAD_DIM,
                                                          il,
                                                          pos);
                        }
                        ds4_gpu_tensor_free(comp_row_view);
                    }
                    if (ok && emit) g->layer_n_comp[il]++;
                    if (comp_counts) comp_counts[t] = g->layer_n_comp[il];
                    if (ok && t == 0) ok = metal_graph_capture_prefix1_attn_state(g, il);
                    ds4_gpu_tensor_free(sc_view);
                    ds4_gpu_tensor_free(kv_view);
                }
            }
            n_comp = g->layer_n_comp[il];
        }
        DS4_METAL_PROFILE_ATTN_STAGE("compressor");

        if (ok && ratio == 4) {
            const uint32_t index_width = coff * DS4_N_INDEXER_HEAD_DIM;
            if (!layer->indexer_compressor_kv || !layer->indexer_compressor_gate ||
                !layer->indexer_compressor_ape || !layer->indexer_compressor_norm ||
                !layer->indexer_attn_q_b || !layer->indexer_proj) {
                fprintf(stderr, "ds4: Metal layer-major prefill needs indexer weights\n");
                ok = false;
            }
            if (ok) ok = ds4_gpu_matmul_f16_tensor(g->batch_comp_kv,
                                                     model->map,
                                                     model->size,
```<｜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.c

```c
tn_factor,
                                                            DS4_ROPE_YARN_BETA_FAST,
                                                            DS4_ROPE_YARN_BETA_SLOW,
                                                            DS4_RMS_EPS) != 0;
                    if (ok && emit) {
                        ds4_gpu_tensor *comp_row_view = ds4_gpu_tensor_view(
                                g->layer_attn_comp_cache[il],
                                (uint64_t)comp_row * DS4_N_HEAD_DIM * sizeof(float),
                                (uint64_t)DS4_N_HEAD_DIM * sizeof(float));
                        ok = comp_row_view &&
                             ds4_gpu_dsv4_fp8_kv_quantize_tensor(comp_row_view,
                                                                   1,
                                                                   DS4_N_HEAD_DIM,
                                                                   DS4_N_ROT) != 0;
                        if (ok) {
                            metal_graph_debug_dump_tensor("KVcompress",
                                                          comp_row_view,
                                                          DS4_N_HEAD_DIM,
                                                          il,
                                                          pos);
                        }
                        ds4_gpu_tensor_free(comp_row_view);
                    }
                    if (ok && emit) g->layer_n_comp[il]++;
                    if (comp_counts) comp_counts[t] = g->layer_n_comp[il];
                    if (ok && t == 0) ok = metal_graph_capture_prefix1_attn_state(g, il);
                    ds4_gpu_tensor_free(sc_view);
                    ds4_gpu_tensor_free(kv_view);
                }
            }
            n_comp = g->layer_n_comp[il];
        }
        DS4_METAL_PROFILE_ATTN_STAGE("compressor");

        if (ok && ratio == 4) {
            const uint32_t index_width = coff * DS4_N_INDEXER_HEAD_DIM;
            if (!layer->indexer_compressor_kv || !layer->indexer_compressor_gate ||
                !layer->indexer_compressor_ape || !layer->indexer_compressor_norm ||
                !layer->indexer_attn_q_b || !layer->indexer_proj) {
                fprintf(stderr, "ds4: Metal layer-major prefill needs indexer weights\n");
                ok = false;
            }
            if (ok) ok = ds4_gpu_matmul_f16_tensor(g->batch_comp_kv,
                                                     model->map,
                                                     model->size,
```

<｜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.c

```c
tn_factor,
                                                            DS4_ROPE_YARN_BETA_FAST,
                                                            DS4_ROPE_YARN_BETA_SLOW,
                                                            DS4_RMS_EPS) != 0;
                    if (ok && emit) {
                        ds4_gpu_tensor *comp_row_view = ds4_gpu_tensor_view(
                                g->layer_attn_comp_cache[il],
                                (uint64_t)comp_row * DS4_N_HEAD_DIM * sizeof(float),
                                (uint64_t)DS4_N_HEAD_DIM * sizeof(float));
                        ok = comp_row_view &&
                             ds4_gpu_dsv4_fp8_kv_quantize_tensor(comp_row_view,
                                                                   1,
                                                                   DS4_N_HEAD_DIM,
                                                                   DS4_N_ROT) != 0;
                        if (ok) {
                            metal_graph_debug_dump_tensor("KVcompress",
                                                          comp_row_view,
                                                          DS4_N_HEAD_DIM,
                                                          il,
                                                          pos);
                        }
                        ds4_gpu_tensor_free(comp_row_view);
                    }
                    if (ok && emit) g->layer_n_comp[il]++;
                    if (comp_counts) comp_counts[t] = g->layer_n_comp[il];
                    if (ok && t == 0) ok = metal_graph_capture_prefix1_attn_state(g, il);
                    ds4_gpu_tensor_free(sc_view);
                    ds4_gpu_tensor_free(kv_view);
                }
            }
            n_comp = g->layer_n_comp[il];
        }
        DS4_METAL_PROFILE_ATTN_STAGE("compressor");

        if (ok && ratio == 4) {
            const uint32_t index_width = coff * DS4_N_INDEXER_HEAD_DIM;
            if (!layer->indexer_compressor_kv || !layer->indexer_compressor_gate ||
                !layer->indexer_compressor_ape || !layer->indexer_compressor_norm ||
                !layer->indexer_attn_q_b || !layer->indexer_proj) {
                fprintf(stderr, "ds4: Metal layer-major prefill needs indexer weights\n");
                ok = false;
            }
            if (ok) ok = ds4_gpu_matmul_f16_tensor(g->batch_comp_kv,
                                                     model->map,
                                                     model->size,
```<｜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.c

```c
ok = ds4_gpu_matmul_f16_tensor(g->batch_comp_kv,
                                                     model->map,
                                                     model->size,
                                                     layer->indexer_compressor_kv->abs_offset,
                                                     DS4_N_EMBD,
                                                     index_width,
                                                     g->batch_attn_norm,
                                                     n_tokens) != 0;
            if (ok) metal_graph_debug_dump_tensor("indexer_comp_kv_raw",
                                                  g->batch_comp_kv,
                                                  (uint64_t)index_width * n_tokens,
                                                  il,
                                                  pos0);
            if (ok) ok = ds4_gpu_matmul_f16_tensor(g->batch_comp_sc,
                                                     model->map,
                                                     model->size,
                                                     layer->indexer_compressor_gate->abs_offset,
                                                     DS4_N_EMBD,
                                                     index_width,
                                                     g->batch_attn_norm,
                                                     n_tokens) != 0;
            if (ok) metal_graph_debug_dump_tensor("indexer_comp_score_raw",
                                                  g->batch_comp_sc,
                                                  (uint64_t)index_width * n_tokens,
                                                  il,
                                                  pos0);
            if (ok) ok = ds4_gpu_matmul_f16_tensor(g->batch_indexer_q,
                                                     model->map,
                                                     model->size,
                                                     layer->indexer_attn_q_b->abs_offset,
                                                     q_rank,
                                                     (uint64_t)DS4_N_INDEXER_HEAD * DS4_N_INDEXER_HEAD_DIM,
                                                     g->batch_qr_norm,
                                                     n_tokens) != 0;
            if (ok) ok = ds4_gpu_rope_tail_tensor(g->batch_indexer_q,
                                                    n_tokens,
                                                    DS4_N_INDEXER_HEAD,
```

<｜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.c

```c
ok = ds4_gpu_matmul_f16_tensor(g->batch_comp_kv,
                                                     model->map,
                                                     model->size,
                                                     layer->indexer_compressor_kv->abs_offset,
                                                     DS4_N_EMBD,
                                                     index_width,
                                                     g->batch_attn_norm,
                                                     n_tokens) != 0;
            if (ok) metal_graph_debug_dump_tensor("indexer_comp_kv_raw",
                                                  g->batch_comp_kv,
                                                  (uint64_t)index_width * n_tokens,
                                                  il,
                                                  pos0);
            if (ok) ok = ds4_gpu_matmul_f16_tensor(g->batch_comp_sc,
                                                     model->map,
                                                     model->size,
                                                     layer->indexer_compressor_gate->abs_offset,
                                                     DS4_N_EMBD,
                                                     index_width,
                                                     g->batch_attn_norm,
                                                     n_tokens) != 0;
            if (ok) metal_graph_debug_dump_tensor("indexer_comp_score_raw",
                                                  g->batch_comp_sc,
                                                  (uint64_t)index_width * n_tokens,
                                                  il,
                                                  pos0);
            if (ok) ok = ds4_gpu_matmul_f16_tensor(g->batch_indexer_q,
                                                     model->map,
                                                     model->size,
                                                     layer->indexer_attn_q_b->abs_offset,
                                                     q_rank,
                                                     (uint64_t)DS4_N_INDEXER_HEAD * DS4_N_INDEXER_HEAD_DIM,
                                                     g->batch_qr_norm,
                                                     n_tokens) != 0;
            if (ok) ok = ds4_gpu_rope_tail_tensor(g->batch_indexer_q,
                                                    n_tokens,
                                                    DS4_N_INDEXER_HEAD,
```<｜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.c

```c
ok = ds4_gpu_matmul_f16_tensor(g->batch_comp_kv,
                                                     model->map,
                                                     model->size,
                                                     layer->indexer_compressor_kv->abs_offset,
                                                     DS4_N_EMBD,
                                                     index_width,
                                                     g->batch_attn_norm,
                                                     n_tokens) != 0;
            if (ok) metal_graph_debug_dump_tensor("indexer_comp_kv_raw",
                                                  g->batch_comp_kv,
                                                  (uint64_t)index_width * n_tokens,
                                                  il,
                                                  pos0);
            if (ok) ok = ds4_gpu_matmul_f16_tensor(g->batch_comp_sc,
                                                     model->map,
                                                     model->size,
                                                     layer->indexer_compressor_gate->abs_offset,
                                                     DS4_N_EMBD,
                                                     index_width,
                                                     g->batch_attn_norm,
                                                     n_tokens) != 0;
            if (ok) metal_graph_debug_dump_tensor("indexer_comp_score_raw",
                                                  g->batch_comp_sc,
                                                  (uint64_t)index_width * n_tokens,
                                                  il,
                                                  pos0);
            if (ok) ok = ds4_gpu_matmul_f16_tensor(g->batch_indexer_q,
                                                     model->map,
                                                     model->size,
                                                     layer->indexer_attn_q_b->abs_offset,
                                                     q_rank,
                                                     (uint64_t)DS4_N_INDEXER_HEAD * DS4_N_INDEXER_HEAD_DIM,
                                                     g->batch_qr_norm,
                                                     n_tokens) != 0;
            if (ok) ok = ds4_gpu_rope_tail_tensor(g->batch_indexer_q,
                                                    n_tokens,
                                                    DS4_N_INDEXER_HEAD,
```

<｜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.c

```c
ok = ds4_gpu_matmul_f16_tensor(g->batch_comp_kv,
                                                     model->map,
                                                     model->size,
                                                     layer->indexer_compressor_kv->abs_offset,
                                                     DS4_N_EMBD,
                                                     index_width,
                                                     g->batch_attn_norm,
                                                     n_tokens) != 0;
            if (ok) metal_graph_debug_dump_tensor("indexer_comp_kv_raw",
                                                  g->batch_comp_kv,
                                                  (uint64_t)index_width * n_tokens,
                                                  il,
                                                  pos0);
            if (ok) ok = ds4_gpu_matmul_f16_tensor(g->batch_comp_sc,
                                                     model->map,
                                                     model->size,
                                                     layer->indexer_compressor_gate->abs_offset,
                                                     DS4_N_EMBD,
                                                     index_width,
                                                     g->batch_attn_norm,
                                                     n_tokens) != 0;
            if (ok) metal_graph_debug_dump_tensor("indexer_comp_score_raw",
                                                  g->batch_comp_sc,
                                                  (uint64_t)index_width * n_tokens,
                                                  il,
                                                  pos0);
            if (ok) ok = ds4_gpu_matmul_f16_tensor(g->batch_indexer_q,
                                                     model->map,
                                                     model->size,
                                                     layer->indexer_attn_q_b->abs_offset,
                                                     q_rank,
                                                     (uint64_t)DS4_N_INDEXER_HEAD * DS4_N_INDEXER_HEAD_DIM,
                                                     g->batch_qr_norm,
                                                     n_tokens) != 0;
            if (ok) ok = ds4_gpu_rope_tail_tensor(g->batch_indexer_q,
                                                    n_tokens,
                                                    DS4_N_INDEXER_HEAD,
```<｜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.c

```c
= ds4_gpu_rope_tail_tensor(g->batch_indexer_q,
                                                    n_tokens,
                                                    DS4_N_INDEXER_HEAD,
                                                    DS4_N_INDEXER_HEAD_DIM,
                                                    DS4_N_ROT,
                                                    pos0,
                                                    compressed ? (uint32_t)DS4_ROPE_ORIG_CTX : 0,
                                                    false,
                                                    freq_base,
                                                    freq_scale,
                                                    ext_factor,
                                                    attn_factor,
                                                    DS4_ROPE_YARN_BETA_FAST,
                                                    DS4_ROPE_YARN_BETA_SLOW) != 0;
            if (ok) ok = ds4_gpu_matmul_f16_tensor(g->batch_indexer_weights,
                                                     model->map,
                                                     model->size,
                                                     layer->indexer_proj->abs_offset,
                                                     DS4_N_EMBD,
                                                     DS4_N_INDEXER_HEAD,
                                                     g->batch_attn_norm,
                                                     n_tokens) != 0;
            if (zero_prefix) {
                if (ok && n_comp > g->layer_comp_cap[il]) {
                    fprintf(stderr, "ds4: Metal layer-major indexer cache capacity exceeded at layer %u\n", il);
                    ok = false;
                }
                if (ok) {
                    ok = ds4_gpu_compressor_prefill_tensor(g->layer_index_comp_cache[il],
                                                             g->layer_index_state_kv[il],
                                                             g->layer_index_state_score[il],
                                                             g->batch_comp_kv,
                                                             g->batch_comp_sc,
                                                             model->map,
                                                             model->size,
                                                             layer->indexer_compressor_ape->abs_offset,
                                                             layer->indexer_compressor_ape->type,
```

<｜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.c

```c
= ds4_gpu_rope_tail_tensor(g->batch_indexer_q,
                                                    n_tokens,
                                                    DS4_N_INDEXER_HEAD,
                                                    DS4_N_INDEXER_HEAD_DIM,
                                                    DS4_N_ROT,
                                                    pos0,
                                                    compressed ? (uint32_t)DS4_ROPE_ORIG_CTX : 0,
                                                    false,
                                                    freq_base,
                                                    freq_scale,
                                                    ext_factor,
                                                    attn_factor,
                                                    DS4_ROPE_YARN_BETA_FAST,
                                                    DS4_ROPE_YARN_BETA_SLOW) != 0;
            if (ok) ok = ds4_gpu_matmul_f16_tensor(g->batch_indexer_weights,
                                                     model->map,
                                                     model->size,
                                                     layer->indexer_proj->abs_offset,
                                                     DS4_N_EMBD,
                                                     DS4_N_INDEXER_HEAD,
                                                     g->batch_attn_norm,
                                                     n_tokens) != 0;
            if (zero_prefix) {
                if (ok && n_comp > g->layer_comp_cap[il]) {
                    fprintf(stderr, "ds4: Metal layer-major indexer cache capacity exceeded at layer %u\n", il);
                    ok = false;
                }
                if (ok) {
                    ok = ds4_gpu_compressor_prefill_tensor(g->layer_index_comp_cache[il],
                                                             g->layer_index_state_kv[il],
                                                             g->layer_index_state_score[il],
                                                             g->batch_comp_kv,
                                                             g->batch_comp_sc,
                                                             model->map,
                                                             model->size,
                                                             layer->indexer_compressor_ape->abs_offset,
                                                             layer->indexer_compressor_ape->type,
```<｜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.c

```c
= ds4_gpu_rope_tail_tensor(g->batch_indexer_q,
                                                    n_tokens,
                                                    DS4_N_INDEXER_HEAD,
                                                    DS4_N_INDEXER_HEAD_DIM,
                                                    DS4_N_ROT,
                                                    pos0,
                                                    compressed ? (uint32_t)DS4_ROPE_ORIG_CTX : 0,
                                                    false,
                                                    freq_base,
                                                    freq_scale,
                                                    ext_factor,
                                                    attn_factor,
                                                    DS4_ROPE_YARN_BETA_FAST,
                                                    DS4_ROPE_YARN_BETA_SLOW) != 0;
            if (ok) ok = ds4_gpu_matmul_f16_tensor(g->batch_indexer_weights,
                                                     model->map,
                                                     model->size,
                                                     layer->indexer_proj->abs_offset,
                                                     DS4_N_EMBD,
                                                     DS4_N_INDEXER_HEAD,
                                                     g->batch_attn_norm,
                                                     n_tokens) != 0;
            if (zero_prefix) {
                if (ok && n_comp > g->layer_comp_cap[il]) {
                    fprintf(stderr, "ds4: Metal layer-major indexer cache capacity exceeded at layer %u\n", il);
                    ok = false;
                }
                if (ok) {
                    ok = ds4_gpu_compressor_prefill_tensor(g->layer_index_comp_cache[il],
                                                             g->layer_index_state_kv[il],
                                                             g->layer_index_state_score[il],
                                                             g->batch_comp_kv,
                                                             g->batch_comp_sc,
                                                             model->map,
                                                             model->size,
                                                             layer->indexer_compressor_ape->abs_offset,
                                                             layer->indexer_compressor_ape->type,
```

<｜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.c

```c
= ds4_gpu_rope_tail_tensor(g->batch_indexer_q,
                                                    n_tokens,
                                                    DS4_N_INDEXER_HEAD,
                                                    DS4_N_INDEXER_HEAD_DIM,
                                                    DS4_N_ROT,
                                                    pos0,
                                                    compressed ? (uint32_t)DS4_ROPE_ORIG_CTX : 0,
                                                    false,
                                                    freq_base,
                                                    freq_scale,
                                                    ext_factor,
                                                    attn_factor,
                                                    DS4_ROPE_YARN_BETA_FAST,
                                                    DS4_ROPE_YARN_BETA_SLOW) != 0;
            if (ok) ok = ds4_gpu_matmul_f16_tensor(g->batch_indexer_weights,
                                                     model->map,
                                                     model->size,
                                                     layer->indexer_proj->abs_offset,
                                                     DS4_N_EMBD,
                                                     DS4_N_INDEXER_HEAD,
                                                     g->batch_attn_norm,
                                                     n_tokens) != 0;
            if (zero_prefix) {
                if (ok && n_comp > g->layer_comp_cap[il]) {
                    fprintf(stderr, "ds4: Metal layer-major indexer cache capacity exceeded at layer %u\n", il);
                    ok = false;
                }
                if (ok) {
                    ok = ds4_gpu_compressor_prefill_tensor(g->layer_index_comp_cache[il],
                                                             g->layer_index_state_kv[il],
                                                             g->layer_index_state_score[il],
                                                             g->batch_comp_kv,
                                                             g->batch_comp_sc,
                                                             model->map,
                                                             model->size,
                                                             layer->indexer_compressor_ape->abs_offset,
                                                             layer->indexer_compressor_ape->type,
```<｜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.c

```c
layer->indexer_compressor_ape->abs_offset,
                                                             layer->indexer_compressor_ape->type,
                                                             layer->indexer_compressor_norm->abs_offset,
                                                             layer->indexer_compressor_norm->type,
                                                             DS4_N_INDEXER_HEAD_DIM,
                                                             ratio,
                                                             pos0,
                                                             n_tokens,
                                                             DS4_N_ROT,
                                                             compressed ? (uint32_t)DS4_ROPE_ORIG_CTX : 0,
                                                             false,
                                                             freq_base,
                                                             freq_scale,
                                                             ext_factor,
                                                             attn_factor,
                                                             DS4_ROPE_YARN_BETA_FAST,
                                                             DS4_ROPE_YARN_BETA_SLOW,
                                                             DS4_RMS_EPS) != 0;
                }
                if (ok) {
                    ok = metal_graph_refresh_ratio4_compressor_state(g,
                                                                     model,
                                                                     g->layer_index_state_kv[il],
                                                                     g->layer_index_state_score[il],
                                                                     layer->indexer_compressor_kv,
                                                                     layer->indexer_compressor_gate,
                                                                     layer->indexer_compressor_ape,
                                                                     DS4_N_INDEXER_HEAD_DIM,
                                                                     index_width,
                                                                     pos0,
                                                                     n_tokens);
                }
                if (ok) {
                    g->layer_n_index_comp[il] = n_comp;
```

<｜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.c

```c
layer->indexer_compressor_ape->abs_offset,
                                                             layer->indexer_compressor_ape->type,
                                                             layer->indexer_compressor_norm->abs_offset,
                                                             layer->indexer_compressor_norm->type,
                                                             DS4_N_INDEXER_HEAD_DIM,
                                                             ratio,
                                                             pos0,
                                                             n_tokens,
                                                             DS4_N_ROT,
                                                             compressed ? (uint32_t)DS4_ROPE_ORIG_CTX : 0,
                                                             false,
                                                             freq_base,
                                                             freq_scale,
                                                             ext_factor,
                                                             attn_factor,
                                                             DS4_ROPE_YARN_BETA_FAST,
                                                             DS4_ROPE_YARN_BETA_SLOW,
                                                             DS4_RMS_EPS) != 0;
                }
                if (ok) {
                    ok = metal_graph_refresh_ratio4_compressor_state(g,
                                                                     model,
                                                                     g->layer_index_state_kv[il],
                                                                     g->layer_index_state_score[il],
                                                                     layer->indexer_compressor_kv,
                                                                     layer->indexer_compressor_gate,
                                                                     layer->indexer_compressor_ape,
                                                                     DS4_N_INDEXER_HEAD_DIM,
                                                                     index_width,
                                                                     pos0,
                                                                     n_tokens);
                }
                if (ok) {
                    g->layer_n_index_comp[il] = n_comp;
```<｜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.c

```c
layer->indexer_compressor_ape->abs_offset,
                                                             layer->indexer_compressor_ape->type,
                                                             layer->indexer_compressor_norm->abs_offset,
                                                             layer->indexer_compressor_norm->type,
                                                             DS4_N_INDEXER_HEAD_DIM,
                                                             ratio,
                                                             pos0,
                                                             n_tokens,
                                                             DS4_N_ROT,
                                                             compressed ? (uint32_t)DS4_ROPE_ORIG_CTX : 0,
                                                             false,
                                                             freq_base,
                                                             freq_scale,
                                                             ext_factor,
                                                             attn_factor,
                                                             DS4_ROPE_YARN_BETA_FAST,
                                                             DS4_ROPE_YARN_BETA_SLOW,
                                                             DS4_RMS_EPS) != 0;
                }
                if (ok) {
                    ok = metal_graph_refresh_ratio4_compressor_state(g,
                                                                     model,
                                                                     g->layer_index_state_kv[il],
                                                                     g->layer_index_state_score[il],
                                                                     layer->indexer_compressor_kv,
                                                                     layer->indexer_compressor_gate,
                                                                     layer->indexer_compressor_ape,
                                                                     DS4_N_INDEXER_HEAD_DIM,
                                                                     index_width,
                                                                     pos0,
                                                                     n_tokens);
                }
                if (ok) {
                    g->layer_n_index_comp[il] = n_comp;
```

<｜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.c

```c
layer->indexer_compressor_ape->abs_offset,
                                                             layer->indexer_compressor_ape->type,
                                                             layer->indexer_compressor_norm->abs_offset,
                                                             layer->indexer_compressor_norm->type,
                                                             DS4_N_INDEXER_HEAD_DIM,
                                                             ratio,
                                                             pos0,
                                                             n_tokens,
                                                             DS4_N_ROT,
                                                             compressed ? (uint32_t)DS4_ROPE_ORIG_CTX : 0,
                                                             false,
                                                             freq_base,
                                                             freq_scale,
                                                             ext_factor,
                                                             attn_factor,
                                                             DS4_ROPE_YARN_BETA_FAST,
                                                             DS4_ROPE_YARN_BETA_SLOW,
                                                             DS4_RMS_EPS) != 0;
                }
                if (ok) {
                    ok = metal_graph_refresh_ratio4_compressor_state(g,
                                                                     model,
                                                                     g->layer_index_state_kv[il],
                                                                     g->layer_index_state_score[il],
                                                                     layer->indexer_compressor_kv,
                                                                     layer->indexer_compressor_gate,
                                                                     layer->indexer_compressor_ape,
                                                                     DS4_N_INDEXER_HEAD_DIM,
                                                                     index_width,
                                                                     pos0,
                                                                     n_tokens);
                }
                if (ok) {
                    g->layer_n_index_comp[il] = n_comp;
```<｜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.c

```c
n_tokens);
                }
                if (ok) {
                    g->layer_n_index_comp[il] = n_comp;
                    for (uint32_t t = 0; t < n_tokens; t++) {
                        index_counts[t] = (pos0 + t + 1u) / ratio;
                    }
                    if (n_comp != 0) {
                        metal_graph_debug_dump_tensor("indexer_KVcompress",
                                                      g->layer_index_comp_cache[il],
                                                      (uint64_t)n_comp * DS4_N_INDEXER_HEAD_DIM,
                                                      il,
                                                      pos0);
                    }
                    metal_graph_debug_dump_tensor("indexer_state_kv",
                                                  g->layer_index_state_kv[il],
                                                  (uint64_t)index_width * coff * ratio,
                                                  il,
                                                  pos0);
                    metal_graph_debug_dump_tensor("indexer_state_score",
                                                  g->layer_index_state_score[il],
                                                  (uint64_t)index_width * coff * ratio,
                                                  il,
                                                  pos0);
                }
            } else {
                const bool aligned_chunk = (pos0 % ratio) == 0u && (n_tokens % ratio) == 0u;
                if (aligned_chunk) {
                    const uint32_t index_before = g->layer_n_index_comp[il];
                    const uint32_t index_chunk = n_tokens / ratio;
                    if (index_before + index_chunk > g->layer_comp_cap[il]) {
                        fprintf(stderr, "ds4: Metal graph indexer compressed KV cache capacity exceeded at layer %u\n", il);
                        ok = false;
                    }
                    ds4_gpu_tensor *index_view = NULL;
                    if (ok) {
                        index_view = ds4_gpu_tensor_view(
                                g->layer_index_comp_cache[il],
                                (uint64_t)index_before * DS4_N_INDEXER_HEAD_DIM * sizeof(float),
                                (uint64_t)index_chunk * DS4_N_INDEXER_HEAD_DIM * sizeof(float));
                        ok = index_view != NULL;
                    }
                    if (ok) {
```

<｜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.c

```c
n_tokens);
                }
                if (ok) {
                    g->layer_n_index_comp[il] = n_comp;
                    for (uint32_t t = 0; t < n_tokens; t++) {
                        index_counts[t] = (pos0 + t + 1u) / ratio;
                    }
                    if (n_comp != 0) {
                        metal_graph_debug_dump_tensor("indexer_KVcompress",
                                                      g->layer_index_comp_cache[il],
                                                      (uint64_t)n_comp * DS4_N_INDEXER_HEAD_DIM,
                                                      il,
                                                      pos0);
                    }
                    metal_graph_debug_dump_tensor("indexer_state_kv",
                                                  g->layer_index_state_kv[il],
                                                  (uint64_t)index_width * coff * ratio,
                                                  il,
                                                  pos0);
                    metal_graph_debug_dump_tensor("indexer_state_score",
                                                  g->layer_index_state_score[il],
                                                  (uint64_t)index_width * coff * ratio,
                                                  il,
                                                  pos0);
                }
            } else {
                const bool aligned_chunk = (pos0 % ratio) == 0u && (n_tokens % ratio) == 0u;
                if (aligned_chunk) {
                    const uint32_t index_before = g->layer_n_index_comp[il];
                    const uint32_t index_chunk = n_tokens / ratio;
                    if (index_before + index_chunk > g->layer_comp_cap[il]) {
                        fprintf(stderr, "ds4: Metal graph indexer compressed KV cache capacity exceeded at layer %u\n", il);
                        ok = false;
                    }
                    ds4_gpu_tensor *index_view = NULL;
                    if (ok) {
                        index_view = ds4_gpu_tensor_view(
                                g->layer_index_comp_cache[il],
                                (uint64_t)index_before * DS4_N_INDEXER_HEAD_DIM * sizeof(float),
                                (uint64_t)index_chunk * DS4_N_INDEXER_HEAD_DIM * sizeof(float));
                        ok = index_view != NULL;
                    }
                    if (ok) {
```<｜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.c

```c
n_tokens);
                }
                if (ok) {
                    g->layer_n_index_comp[il] = n_comp;
                    for (uint32_t t = 0; t < n_tokens; t++) {
                        index_counts[t] = (pos0 + t + 1u) / ratio;
                    }
                    if (n_comp != 0) {
                        metal_graph_debug_dump_tensor("indexer_KVcompress",
                                                      g->layer_index_comp_cache[il],
                                                      (uint64_t)n_comp * DS4_N_INDEXER_HEAD_DIM,
                                                      il,
                                                      pos0);
                    }
                    metal_graph_debug_dump_tensor("indexer_state_kv",
                                                  g->layer_index_state_kv[il],
                                                  (uint64_t)index_width * coff * ratio,
                                                  il,
                                                  pos0);
                    metal_graph_debug_dump_tensor("indexer_state_score",
                                                  g->layer_index_state_score[il],
                                                  (uint64_t)index_width * coff * ratio,
                                                  il,
                                                  pos0);
                }
            } else {
                const bool aligned_chunk = (pos0 % ratio) == 0u && (n_tokens % ratio) == 0u;
                if (aligned_chunk) {
                    const uint32_t index_before = g->layer_n_index_comp[il];
                    const uint32_t index_chunk = n_tokens / ratio;
                    if (index_before + index_chunk > g->layer_comp_cap[il]) {
                        fprintf(stderr, "ds4: Metal graph indexer compressed KV cache capacity exceeded at layer %u\n", il);
                        ok = false;
                    }
                    ds4_gpu_tensor *index_view = NULL;
                    if (ok) {
                        index_view = ds4_gpu_tensor_view(
                                g->layer_index_comp_cache[il],
                                (uint64_t)index_before * DS4_N_INDEXER_HEAD_DIM * sizeof(float),
                                (uint64_t)index_chunk * DS4_N_INDEXER_HEAD_DIM * sizeof(float));
                        ok = index_view != NULL;
                    }
                    if (ok) {
```

<｜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.c

```c
n_tokens);
                }
                if (ok) {
                    g->layer_n_index_comp[il] = n_comp;
                    for (uint32_t t = 0; t < n_tokens; t++) {
                        index_counts[t] = (pos0 + t + 1u) / ratio;
                    }
                    if (n_comp != 0) {
                        metal_graph_debug_dump_tensor("indexer_KVcompress",
                                                      g->layer_index_comp_cache[il],
                                                      (uint64_t)n_comp * DS4_N_INDEXER_HEAD_DIM,
                                                      il,
                                                      pos0);
                    }
                    metal_graph_debug_dump_tensor("indexer_state_kv",
                                                  g->layer_index_state_kv[il],
                                                  (uint64_t)index_width * coff * ratio,
                                                  il,
                                                  pos0);
                    metal_graph_debug_dump_tensor("indexer_state_score",
                                                  g->layer_index_state_score[il],
                                                  (uint64_t)index_width * coff * ratio,
                                                  il,
                                                  pos0);
                }
            } else {
                const bool aligned_chunk = (pos0 % ratio) == 0u && (n_tokens % ratio) == 0u;
                if (aligned_chunk) {
                    const uint32_t index_before = g->layer_n_index_comp[il];
                    const uint32_t index_chunk = n_tokens / ratio;
                    if (index_before + index_chunk > g->layer_comp_cap[il]) {
                        fprintf(stderr, "ds4: Metal graph indexer compressed KV cache capacity exceeded at layer %u\n", il);
                        ok = false;
                    }
                    ds4_gpu_tensor *index_view = NULL;
                    if (ok) {
                        index_view = ds4_gpu_tensor_view(
                                g->layer_index_comp_cache[il],
                                (uint64_t)index_before * DS4_N_INDEXER_HEAD_DIM * sizeof(float),
                                (uint64_t)index_chunk * DS4_N_INDEXER_HEAD_DIM * sizeof(float));
                        ok = index_view != NULL;
                    }
                    if (ok) {
```<｜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.c

```c
(uint64_t)index_chunk * DS4_N_INDEXER_HEAD_DIM * sizeof(float));
                        ok = index_view != NULL;
                    }
                    if (ok) {
                        ok = ds4_gpu_compressor_prefill_ratio4_replay_tensor(
                                index_view,
                                g->layer_index_state_kv[il],
                                g->layer_index_state_score[il],
                                g->batch_comp_kv,
                                g->batch_comp_sc,
                                model->map,
                                model->size,
                                layer->indexer_compressor_ape->abs_offset,
                                layer->indexer_compressor_ape->type,
                                layer->indexer_compressor_norm->abs_offset,
                                layer->indexer_compressor_norm->type,
                                DS4_N_INDEXER_HEAD_DIM,
                                pos0,
                                n_tokens,
                                DS4_N_ROT,
                                compressed ? (uint32_t)DS4_ROPE_ORIG_CTX : 0,
                                false,
                                freq_base,
                                freq_scale,
                                ext_factor,
                                attn_factor,
                                DS4_ROPE_YARN_BETA_FAST,
                                DS4_ROPE_YARN_BETA_SLOW,
                                DS4_RMS_EPS) != 0;
                    }
                    if (ok) {
                        ok = metal_graph_refresh_ratio4_compressor_state(g,
                                                                         model,
                                                                         g->layer_index_state_kv[il],
                                                                         g->layer_index_state_score[il],
                                                                         layer->indexer_compressor_kv,
                                                                         layer->indexer_compressor_gate,
                                                                         layer->indexer_compressor_ape,
                                                                         DS4_N_INDEXER_HEAD_DIM,
                                                                         index_width,
                                                                         pos0,
```

<｜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.c

```c
(uint64_t)index_chunk * DS4_N_INDEXER_HEAD_DIM * sizeof(float));
                        ok = index_view != NULL;
                    }
                    if (ok) {
                        ok = ds4_gpu_compressor_prefill_ratio4_replay_tensor(
                                index_view,
                                g->layer_index_state_kv[il],
                                g->layer_index_state_score[il],
                                g->batch_comp_kv,
                                g->batch_comp_sc,
                                model->map,
                                model->size,
                                layer->indexer_compressor_ape->abs_offset,
                                layer->indexer_compressor_ape->type,
                                layer->indexer_compressor_norm->abs_offset,
                                layer->indexer_compressor_norm->type,
                                DS4_N_INDEXER_HEAD_DIM,
                                pos0,
                                n_tokens,
                                DS4_N_ROT,
                                compressed ? (uint32_t)DS4_ROPE_ORIG_CTX : 0,
                                false,
                                freq_base,
                                freq_scale,
                                ext_factor,
                                attn_factor,
                                DS4_ROPE_YARN_BETA_FAST,
                                DS4_ROPE_YARN_BETA_SLOW,
                                DS4_RMS_EPS) != 0;
                    }
                    if (ok) {
                        ok = metal_graph_refresh_ratio4_compressor_state(g,
                                                                         model,
                                                                         g->layer_index_state_kv[il],
                                                                         g->layer_index_state_score[il],
                                                                         layer->indexer_compressor_kv,
                                                                         layer->indexer_compressor_gate,
                                                                         layer->indexer_compressor_ape,
                                                                         DS4_N_INDEXER_HEAD_DIM,
                                                                         index_width,
                                                                         pos0,
```<｜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.c

```c
(uint64_t)index_chunk * DS4_N_INDEXER_HEAD_DIM * sizeof(float));
                        ok = index_view != NULL;
                    }
                    if (ok) {
                        ok = ds4_gpu_compressor_prefill_ratio4_replay_tensor(
                                index_view,
                                g->layer_index_state_kv[il],
                                g->layer_index_state_score[il],
                                g->batch_comp_kv,
                                g->batch_comp_sc,
                                model->map,
                                model->size,
                                layer->indexer_compressor_ape->abs_offset,
                                layer->indexer_compressor_ape->type,
                                layer->indexer_compressor_norm->abs_offset,
                                layer->indexer_compressor_norm->type,
                                DS4_N_INDEXER_HEAD_DIM,
                                pos0,
                                n_tokens,
                                DS4_N_ROT,
                                compressed ? (uint32_t)DS4_ROPE_ORIG_CTX : 0,
                                false,
                                freq_base,
                                freq_scale,
                                ext_factor,
                                attn_factor,
                                DS4_ROPE_YARN_BETA_FAST,
                                DS4_ROPE_YARN_BETA_SLOW,
                                DS4_RMS_EPS) != 0;
                    }
                    if (ok) {
                        ok = metal_graph_refresh_ratio4_compressor_state(g,
                                                                         model,
                                                                         g->layer_index_state_kv[il],
                                                                         g->layer_index_state_score[il],
                                                                         layer->indexer_compressor_kv,
                                                                         layer->indexer_compressor_gate,
                                                                         layer->indexer_compressor_ape,
                                                                         DS4_N_INDEXER_HEAD_DIM,
                                                                         index_width,
                                                                         pos0,
```

<｜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.c

```c
(uint64_t)index_chunk * DS4_N_INDEXER_HEAD_DIM * sizeof(float));
                        ok = index_view != NULL;
                    }
                    if (ok) {
                        ok = ds4_gpu_compressor_prefill_ratio4_replay_tensor(
                                index_view,
                                g->layer_index_state_kv[il],
                                g->layer_index_state_score[il],
                                g->batch_comp_kv,
                                g->batch_comp_sc,
                                model->map,
                                model->size,
                                layer->indexer_compressor_ape->abs_offset,
                                layer->indexer_compressor_ape->type,
                                layer->indexer_compressor_norm->abs_offset,
                                layer->indexer_compressor_norm->type,
                                DS4_N_INDEXER_HEAD_DIM,
                                pos0,
                                n_tokens,
                                DS4_N_ROT,
                                compressed ? (uint32_t)DS4_ROPE_ORIG_CTX : 0,
                                false,
                                freq_base,
                                freq_scale,
                                ext_factor,
                                attn_factor,
                                DS4_ROPE_YARN_BETA_FAST,
                                DS4_ROPE_YARN_BETA_SLOW,
                                DS4_RMS_EPS) != 0;
                    }
                    if (ok) {
                        ok = metal_graph_refresh_ratio4_compressor_state(g,
                                                                         model,
                                                                         g->layer_index_state_kv[il],
                                                                         g->layer_index_state_score[il],
                                                                         layer->indexer_compressor_kv,
                                                                         layer->indexer_compressor_gate,
                                                                         layer->indexer_compressor_ape,
                                                                         DS4_N_INDEXER_HEAD_DIM,
                                                                         index_width,
                                                                         pos0,
```<｜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.c

```c
DEXER_HEAD_DIM,
                                                                         index_width,
                                                                         pos0,
                                                                         n_tokens);
                    }
                    if (ok) {
                        g->layer_n_index_comp[il] = index_before + index_chunk;
                        if (index_counts) {
                            for (uint32_t t = 0; t < n_tokens; t++) {
                                index_counts[t] = (pos0 + t + 1u) / ratio;
                            }
                        }
                        metal_graph_debug_dump_tensor("indexer_KVcompress",
                                                      index_view,
                                                      (uint64_t)index_chunk * DS4_N_INDEXER_HEAD_DIM,
                                                      il,
                                                      pos0);
                        metal_graph_debug_dump_tensor("indexer_state_kv",
                                                      g->layer_index_state_kv[il],
                                                      (uint64_t)index_width * coff * ratio,
                                                      il,
                                                      pos0);
                        metal_graph_debug_dump_tensor("indexer_state_score",
                                                      g->layer_index_state_score[il],
                                                      (uint64_t)index_width * coff * ratio,
                                                      il,
                                                      pos0);
                    }
                    ds4_gpu_tensor_free(index_view);
                } else {
                    for (uint32_t t = 0; ok && t < n_tokens; t++) {
                        const uint32_t pos = pos0 + t;
                        const bool emit = ((pos + 1u) % ratio) == 0u;
                        if (emit && g->layer_n_index_comp[il] >= g->layer_comp_cap[il]) {
                            fprintf(stderr, "ds4: Metal graph indexer compressed KV cache capacity exceeded at layer %u\n", il);
                            ok = false;
                            break;
                        }
                        ds4_gpu_tensor *kv_view = metal_graph_tensor_row_view(g->batch_comp_kv, t, index_width);
                        ds4_gpu_tensor *sc_view = metal_graph_tensor_row_view(g->batch_comp_sc, t, index_width);
```

<｜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.c

```c
DEXER_HEAD_DIM,
                                                                         index_width,
                                                                         pos0,
                                                                         n_tokens);
                    }
                    if (ok) {
                        g->layer_n_index_comp[il] = index_before + index_chunk;
                        if (index_counts) {
                            for (uint32_t t = 0; t < n_tokens; t++) {
                                index_counts[t] = (pos0 + t + 1u) / ratio;
                            }
                        }
                        metal_graph_debug_dump_tensor("indexer_KVcompress",
                                                      index_view,
                                                      (uint64_t)index_chunk * DS4_N_INDEXER_HEAD_DIM,
                                                      il,
                                                      pos0);
                        metal_graph_debug_dump_tensor("indexer_state_kv",
                                                      g->layer_index_state_kv[il],
                                                      (uint64_t)index_width * coff * ratio,
                                                      il,
                                                      pos0);
                        metal_graph_debug_dump_tensor("indexer_state_score",
                                                      g->layer_index_state_score[il],
                                                      (uint64_t)index_width * coff * ratio,
                                                      il,
                                                      pos0);
                    }
                    ds4_gpu_tensor_free(index_view);
                } else {
                    for (uint32_t t = 0; ok && t < n_tokens; t++) {
                        const uint32_t pos = pos0 + t;
                        const bool emit = ((pos + 1u) % ratio) == 0u;
                        if (emit && g->layer_n_index_comp[il] >= g->layer_comp_cap[il]) {
                            fprintf(stderr, "ds4: Metal graph indexer compressed KV cache capacity exceeded at layer %u\n", il);
                            ok = false;
                            break;
                        }
                        ds4_gpu_tensor *kv_view = metal_graph_tensor_row_view(g->batch_comp_kv, t, index_width);
                        ds4_gpu_tensor *sc_view = metal_graph_tensor_row_view(g->batch_comp_sc, t, index_width);
```<｜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.c

```c
DEXER_HEAD_DIM,
                                                                         index_width,
                                                                         pos0,
                                                                         n_tokens);
                    }
                    if (ok) {
                        g->layer_n_index_comp[il] = index_before + index_chunk;
                        if (index_counts) {
                            for (uint32_t t = 0; t < n_tokens; t++) {
                                index_counts[t] = (pos0 + t + 1u) / ratio;
                            }
                        }
                        metal_graph_debug_dump_tensor("indexer_KVcompress",
                                                      index_view,
                                                      (uint64_t)index_chunk * DS4_N_INDEXER_HEAD_DIM,
                                                      il,
                                                      pos0);
                        metal_graph_debug_dump_tensor("indexer_state_kv",
                                                      g->layer_index_state_kv[il],
                                                      (uint64_t)index_width * coff * ratio,
                                                      il,
                                                      pos0);
                        metal_graph_debug_dump_tensor("indexer_state_score",
                                                      g->layer_index_state_score[il],
                                                      (uint64_t)index_width * coff * ratio,
                                                      il,
                                                      pos0);
                    }
                    ds4_gpu_tensor_free(index_view);
                } else {
                    for (uint32_t t = 0; ok && t < n_tokens; t++) {
                        const uint32_t pos = pos0 + t;
                        const bool emit = ((pos + 1u) % ratio) == 0u;
                        if (emit && g->layer_n_index_comp[il] >= g->layer_comp_cap[il]) {
                            fprintf(stderr, "ds4: Metal graph indexer compressed KV cache capacity exceeded at layer %u\n", il);
                            ok = false;
                            break;
                        }
                        ds4_gpu_tensor *kv_view = metal_graph_tensor_row_view(g->batch_comp_kv, t, index_width);
                        ds4_gpu_tensor *sc_view = metal_graph_tensor_row_view(g->batch_comp_sc, t, index_width);
```

<｜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.c

```c
DEXER_HEAD_DIM,
                                                                         index_width,
                                                                         pos0,
                                                                         n_tokens);
                    }
                    if (ok) {
                        g->layer_n_index_comp[il] = index_before + index_chunk;
                        if (index_counts) {
                            for (uint32_t t = 0; t < n_tokens; t++) {
                                index_counts[t] = (pos0 + t + 1u) / ratio;
                            }
                        }
                        metal_graph_debug_dump_tensor("indexer_KVcompress",
                                                      index_view,
                                                      (uint64_t)index_chunk * DS4_N_INDEXER_HEAD_DIM,
                                                      il,
                                                      pos0);
                        metal_graph_debug_dump_tensor("indexer_state_kv",
                                                      g->layer_index_state_kv[il],
                                                      (uint64_t)index_width * coff * ratio,
                                                      il,
                                                      pos0);
                        metal_graph_debug_dump_tensor("indexer_state_score",
                                                      g->layer_index_state_score[il],
                                                      (uint64_t)index_width * coff * ratio,
                                                      il,
                                                      pos0);
                    }
                    ds4_gpu_tensor_free(index_view);
                } else {
                    for (uint32_t t = 0; ok && t < n_tokens; t++) {
                        const uint32_t pos = pos0 + t;
                        const bool emit = ((pos + 1u) % ratio) == 0u;
                        if (emit && g->layer_n_index_comp[il] >= g->layer_comp_cap[il]) {
                            fprintf(stderr, "ds4: Metal graph indexer compressed KV cache capacity exceeded at layer %u\n", il);
                            ok = false;
                            break;
                        }
                        ds4_gpu_tensor *kv_view = metal_graph_tensor_row_view(g->batch_comp_kv, t, index_width);
                        ds4_gpu_tensor *sc_view = metal_graph_tensor_row_view(g->batch_comp_sc, t, index_width);
```<｜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.c

```c
ew = metal_graph_tensor_row_view(g->batch_comp_kv, t, index_width);
                        ds4_gpu_tensor *sc_view = metal_graph_tensor_row_view(g->batch_comp_sc, t, index_width);
                        const uint32_t index_row = g->layer_n_index_comp[il];
                        ok = kv_view && sc_view &&
                             ds4_gpu_compressor_update_tensor(kv_view,
                                                                sc_view,
                                                                g->layer_index_state_kv[il],
                                                                g->layer_index_state_score[il],
                                                                g->layer_index_comp_cache[il],
                                                                model->map,
                                                                model->size,
                                                                layer->indexer_compressor_ape->abs_offset,
                                                                layer->indexer_compressor_ape->type,
                                                                layer->indexer_compressor_norm->abs_offset,
                                                                layer->indexer_compressor_norm->type,
                                                                DS4_N_INDEXER_HEAD_DIM,
                                                                ratio,
                                                                pos,
                                                                index_row,
                                                                DS4_N_ROT,
                                                                compressed ? (uint32_t)DS4_ROPE_ORIG_CTX : 0,
                                                                freq_base,
                                                                freq_scale,
                                                                ext_factor,
                                                                attn_factor,
                                                                DS4_ROPE_YARN_BETA_FAST,
                                                                DS4_ROPE_YARN_BETA_SLOW,
                                                                DS4_RMS_EPS) != 0;
                        if (ok && emit) g->layer_n_index_comp[il]++;
                        if (index_counts) index_counts[t] = g->layer_n_index_comp[il];
```

<｜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.c

```c
ew = metal_graph_tensor_row_view(g->batch_comp_kv, t, index_width);
                        ds4_gpu_tensor *sc_view = metal_graph_tensor_row_view(g->batch_comp_sc, t, index_width);
                        const uint32_t index_row = g->layer_n_index_comp[il];
                        ok = kv_view && sc_view &&
                             ds4_gpu_compressor_update_tensor(kv_view,
                                                                sc_view,
                                                                g->layer_index_state_kv[il],
                                                                g->layer_index_state_score[il],
                                                                g->layer_index_comp_cache[il],
                                                                model->map,
                                                                model->size,
                                                                layer->indexer_compressor_ape->abs_offset,
                                                                layer->indexer_compressor_ape->type,
                                                                layer->indexer_compressor_norm->abs_offset,
                                                                layer->indexer_compressor_norm->type,
                                                                DS4_N_INDEXER_HEAD_DIM,
                                                                ratio,
                                                                pos,
                                                                index_row,
                                                                DS4_N_ROT,
                                                                compressed ? (uint32_t)DS4_ROPE_ORIG_CTX : 0,
                                                                freq_base,
                                                                freq_scale,
                                                                ext_factor,
                                                                attn_factor,
                                                                DS4_ROPE_YARN_BETA_FAST,
                                                                DS4_ROPE_YARN_BETA_SLOW,
                                                                DS4_RMS_EPS) != 0;
                        if (ok && emit) g->layer_n_index_comp[il]++;
                        if (index_counts) index_counts[t] = g->layer_n_index_comp[il];
```<｜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.c

```c
ew = metal_graph_tensor_row_view(g->batch_comp_kv, t, index_width);
                        ds4_gpu_tensor *sc_view = metal_graph_tensor_row_view(g->batch_comp_sc, t, index_width);
                        const uint32_t index_row = g->layer_n_index_comp[il];
                        ok = kv_view && sc_view &&
                             ds4_gpu_compressor_update_tensor(kv_view,
                                                                sc_view,
                                                                g->layer_index_state_kv[il],
                                                                g->layer_index_state_score[il],
                                                                g->layer_index_comp_cache[il],
                                                                model->map,
                                                                model->size,
                                                                layer->indexer_compressor_ape->abs_offset,
                                                                layer->indexer_compressor_ape->type,
                                                                layer->indexer_compressor_norm->abs_offset,
                                                                layer->indexer_compressor_norm->type,
                                                                DS4_N_INDEXER_HEAD_DIM,
                                                                ratio,
                                                                pos,
                                                                index_row,
                                                                DS4_N_ROT,
                                                                compressed ? (uint32_t)DS4_ROPE_ORIG_CTX : 0,
                                                                freq_base,
                                                                freq_scale,
                                                                ext_factor,
                                                                attn_factor,
                                                                DS4_ROPE_YARN_BETA_FAST,
                                                                DS4_ROPE_YARN_BETA_SLOW,
                                                                DS4_RMS_EPS) != 0;
                        if (ok && emit) g->layer_n_index_comp[il]++;
                        if (index_counts) index_counts[t] = g->layer_n_index_comp[il];
```

<｜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.c

```c
ew = metal_graph_tensor_row_view(g->batch_comp_kv, t, index_width);
                        ds4_gpu_tensor *sc_view = metal_graph_tensor_row_view(g->batch_comp_sc, t, index_width);
                        const uint32_t index_row = g->layer_n_index_comp[il];
                        ok = kv_view && sc_view &&
                             ds4_gpu_compressor_update_tensor(kv_view,
                                                                sc_view,
                                                                g->layer_index_state_kv[il],
                                                                g->layer_index_state_score[il],
                                                                g->layer_index_comp_cache[il],
                                                                model->map,
                                                                model->size,
                                                                layer->indexer_compressor_ape->abs_offset,
                                                                layer->indexer_compressor_ape->type,
                                                                layer->indexer_compressor_norm->abs_offset,
                                                                layer->indexer_compressor_norm->type,
                                                                DS4_N_INDEXER_HEAD_DIM,
                                                                ratio,
                                                                pos,
                                                                index_row,
                                                                DS4_N_ROT,
                                                                compressed ? (uint32_t)DS4_ROPE_ORIG_CTX : 0,
                                                                freq_base,
                                                                freq_scale,
                                                                ext_factor,
                                                                attn_factor,
                                                                DS4_ROPE_YARN_BETA_FAST,
                                                                DS4_ROPE_YARN_BETA_SLOW,
                                                                DS4_RMS_EPS) != 0;
                        if (ok && emit) g->layer_n_index_comp[il]++;
                        if (index_counts) index_counts[t] = g->layer_n_index_comp[il];
```<｜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.c

```c
inline float f16_to_f32(uint16_t h) {
#if defined(__ARM_NEON)
    const float16x4_t hv = vreinterpret_f16_u16(vdup_n_u16(h));
    return vgetq_lane_f32(vcvt_f32_f16(hv), 0);
#else
    uint32_t sign = (uint32_t)(h & 0x8000) << 16;
    uint32_t exp  = (h >> 10) & 0x1f;
    uint32_t mant = h & 0x03ff;
    uint32_t bits;

    if (exp == 0) {
        if (mant == 0) {
            bits = sign;
        } else {
            exp = 1;
            while ((mant & 0x0400) == 0) {
                mant <<= 1;
                exp--;
            }
            mant &= 0x03ff;
            bits = sign | ((exp + 127 - 15) << 23) | (mant << 13);
        }
    } else if (exp == 31) {
        bits = sign | 0x7f800000u | (mant << 13);
    } else {
        bits = sign | ((exp + 127 - 15) << 23) | (mant << 13);
    }

    float f;
    memcpy(&f, &bits, sizeof(f));
    return f;
#endif
}

static inline uint16_t f32_to_f16(float f) {
#if defined(__ARM_NEON)
    const float32x4_t fv = vdupq_n_f32(f);
    const float16x4_t hv = vcvt_f16_f32(fv);
    return vget_lane_u16(vreinterpret_u16_f16(hv), 0);
#else
    uint32_t bits;
    memcpy(&bits, &f, sizeof(bits));

    const uint32_t sign = (bits >> 16) & 0x8000u;
    int32_t exp = (int32_t)((bits >> 23) & 0xffu) - 127 + 15;
    uint32_t mant = bits & 0x7fffffu;

    if (exp <= 0) {
        if (exp < -10) return (uint16_t)sign;
        mant |= 0x800000u;
        const uint32_t shift = (uint32_t)(14 - exp);
        uint32_t half_mant = mant >> shift;
        const uint32_t round_bit = (mant >> (shift - 1)) & 1u;
        const uint32_t sticky = mant & ((1u << (shift - 1)) - 1u);
        if (round_bit && (sticky || (half_mant & 1u))) half_mant++;
        return (uint16_t)(sign | half_mant);
    }

    if (exp >= 31) {
        if (((bits >> 23) & 0xffu) == 0xffu && mant != 0) {
            return (uint16_t)(sign | 0x7e00u);
        }
        return (uint16_t)(sign | 0x7c00u);
    }

    uint32_t half = sign | ((uint32_t)exp << 10) | (mant >> 13);
    const uint32_t round = mant & 0x1fffu;
    if (round > 0x1000u || (round == 0x1000u && (half & 1u))) half++;
    return (uint16_t)half;
#endif
}

static void f16_round_inplace_cpu(float *x, uint32_t n) {
    for (uint32_t i = 0; i < n; i++) x[i] = f16_to_f32(f32_to_f16(x[i]));
}

static float dsv4_e4m3fn_value_cpu(int i) {
    static const float exp_scale[16] = {
        0.0f, 0.015625f, 0.03125f, 0.0625f,
        0.125f, 0.25f, 0.5f, 1.0f,
        2.0f, 4.0f, 8.0f, 16.0f,
        32.0f, 64.0f, 128.0f, 256.0f,
    };

    const int exp = (i >> 3) & 0x0f;
    const int mant = i & 0x07;
```

<｜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.c

```c
inline float f16_to_f32(uint16_t h) {
#if defined(__ARM_NEON)
    const float16x4_t hv = vreinterpret_f16_u16(vdup_n_u16(h));
    return vgetq_lane_f32(vcvt_f32_f16(hv), 0);
#else
    uint32_t sign = (uint32_t)(h & 0x8000) << 16;
    uint32_t exp  = (h >> 10) & 0x1f;
    uint32_t mant = h & 0x03ff;
    uint32_t bits;

    if (exp == 0) {
        if (mant == 0) {
            bits = sign;
        } else {
            exp = 1;
            while ((mant & 0x0400) == 0) {
                mant <<= 1;
                exp--;
            }
            mant &= 0x03ff;
            bits = sign | ((exp + 127 - 15) << 23) | (mant << 13);
        }
    } else if (exp == 31) {
        bits = sign | 0x7f800000u | (mant << 13);
    } else {
        bits = sign | ((exp + 127 - 15) << 23) | (mant << 13);
    }

    float f;
    memcpy(&f, &bits, sizeof(f));
    return f;
#endif
}

static inline uint16_t f32_to_f16(float f) {
#if defined(__ARM_NEON)
    const float32x4_t fv = vdupq_n_f32(f);
    const float16x4_t hv = vcvt_f16_f32(fv);
    return vget_lane_u16(vreinterpret_u16_f16(hv), 0);
#else
    uint32_t bits;
    memcpy(&bits, &f, sizeof(bits));

    const uint32_t sign = (bits >> 16) & 0x8000u;
    int32_t exp = (int32_t)((bits >> 23) & 0xffu) - 127 + 15;
    uint32_t mant = bits & 0x7fffffu;

    if (exp <= 0) {
        if (exp < -10) return (uint16_t)sign;
        mant |= 0x800000u;
        const uint32_t shift = (uint32_t)(14 - exp);
        uint32_t half_mant = mant >> shift;
        const uint32_t round_bit = (mant >> (shift - 1)) & 1u;
        const uint32_t sticky = mant & ((1u << (shift - 1)) - 1u);
        if (round_bit && (sticky || (half_mant & 1u))) half_mant++;
        return (uint16_t)(sign | half_mant);
    }

    if (exp >= 31) {
        if (((bits >> 23) & 0xffu) == 0xffu && mant != 0) {
            return (uint16_t)(sign | 0x7e00u);
        }
        return (uint16_t)(sign | 0x7c00u);
    }

    uint32_t half = sign | ((uint32_t)exp << 10) | (mant >> 13);
    const uint32_t round = mant & 0x1fffu;
    if (round > 0x1000u || (round == 0x1000u && (half & 1u))) half++;
    return (uint16_t)half;
#endif
}

static void f16_round_inplace_cpu(float *x, uint32_t n) {
    for (uint32_t i = 0; i < n; i++) x[i] = f16_to_f32(f32_to_f16(x[i]));
}

static float dsv4_e4m3fn_value_cpu(int i) {
    static const float exp_scale[16] = {
        0.0f, 0.015625f, 0.03125f, 0.0625f,
        0.125f, 0.25f, 0.5f, 1.0f,
        2.0f, 4.0f, 8.0f, 16.0f,
        32.0f, 64.0f, 128.0f, 256.0f,
    };

    const int exp = (i >> 3) & 0x0f;
    const int mant = i & 0x07;
```<｜Assistant｜></think>