metal: add col2im_1d op (f32/f16/bf16) (#25176)

* metal: add col2im_1d op (f32/f16/bf16)

Gather kernel mirroring the CPU/CUDA path: each output (t_out, oc)
reads its ceil(K/s0) source columns with an F32 accumulator, a single
write and no atomics. One thread per output element, 256 per
threadgroup.

* metal: check dst contiguity and type match in supports_op for COL2IM_1D

Align the GGML_OP_COL2IM_1D predicate with the CPU, CUDA, and Vulkan
backends: the kernel writes dst with linear indexing and assumes the
same type as src0, so supports_op must also require a contiguous dst
and op->type == op->src[0]->type.

* Update ggml/src/ggml-metal/ggml-metal.metal

Co-authored-by: YiChen Lv <63285796+forforever73@users.noreply.github.com>

---------

Co-authored-by: YiChen Lv <63285796+forforever73@users.noreply.github.com>

ggml/src/ggml-metal/ggml-metal-device.cpp

@@ -1800,6 +1800,26 @@ ggml_metal_pipeline_with_params ggml_metal_library_get_pipeline_conv_transpose_1
     return res;
 }
 
+ggml_metal_pipeline_with_params ggml_metal_library_get_pipeline_col2im_1d(ggml_metal_library_t lib, const ggml_tensor * op) {
+    assert(op->op == GGML_OP_COL2IM_1D);
+
+    GGML_ASSERT(ggml_is_contiguous(op->src[0]));
+    GGML_ASSERT(op->src[0]->type == GGML_TYPE_F32 || op->src[0]->type == GGML_TYPE_F16 || op->src[0]->type == GGML_TYPE_BF16);
+
+    char base[256];
+    char name[256];
+
+    snprintf(base, 256, "kernel_col2im_1d_%s", ggml_type_name(op->src[0]->type));
+    snprintf(name, 256, "%s", base);
+
+    ggml_metal_pipeline_with_params res = ggml_metal_library_get_pipeline(lib, name);
+    if (!res.pipeline) {
+        res = ggml_metal_library_compile_pipeline(lib, base, name, nullptr);
+    }
+
+    return res;
+}
+
 ggml_metal_pipeline_with_params ggml_metal_library_get_pipeline_conv_transpose_2d(ggml_metal_library_t lib, const ggml_tensor * op) {
     assert(op->op == GGML_OP_CONV_TRANSPOSE_2D);
 

ggml/src/ggml-metal/ggml-metal-device.h

@@ -150,6 +150,7 @@ struct ggml_metal_pipeline_with_params ggml_metal_library_get_pipeline_rope
 struct ggml_metal_pipeline_with_params ggml_metal_library_get_pipeline_im2col            (ggml_metal_library_t lib, const struct ggml_tensor * op);
 struct ggml_metal_pipeline_with_params ggml_metal_library_get_pipeline_conv_transpose_1d (ggml_metal_library_t lib, const struct ggml_tensor * op);
 struct ggml_metal_pipeline_with_params ggml_metal_library_get_pipeline_conv_transpose_2d (ggml_metal_library_t lib, const struct ggml_tensor * op);
+struct ggml_metal_pipeline_with_params ggml_metal_library_get_pipeline_col2im_1d         (ggml_metal_library_t lib, const struct ggml_tensor * op);
 struct ggml_metal_pipeline_with_params ggml_metal_library_get_pipeline_conv_2d           (ggml_metal_library_t lib, const struct ggml_tensor * op);
 struct ggml_metal_pipeline_with_params ggml_metal_library_get_pipeline_conv_3d           (ggml_metal_library_t lib, const struct ggml_tensor * op);
 struct ggml_metal_pipeline_with_params ggml_metal_library_get_pipeline_upscale           (ggml_metal_library_t lib, const struct ggml_tensor * op);

ggml/src/ggml-metal/ggml-metal-device.m

@@ -1157,6 +1157,11 @@ bool ggml_metal_device_supports_op(ggml_metal_device_t dev, const struct ggml_te
                 (op->src[0]->type == GGML_TYPE_F16 || op->src[0]->type == GGML_TYPE_F32) &&
                 op->src[1]->type == GGML_TYPE_F32 &&
                 op->type == GGML_TYPE_F32;
+        case GGML_OP_COL2IM_1D:
+            return (op->src[0]->type == GGML_TYPE_F32 || op->src[0]->type == GGML_TYPE_F16 || op->src[0]->type == GGML_TYPE_BF16) &&
+                op->type == op->src[0]->type &&
+                ggml_is_contiguous(op->src[0]) &&
+                ggml_is_contiguous(op);
         case GGML_OP_CONV_3D:
             return ggml_is_contiguous(op->src[0]) &&
                    ggml_is_contiguous(op->src[1]) &&

ggml/src/ggml-metal/ggml-metal-impl.h

@@ -603,6 +603,16 @@ typedef struct {
     uint64_t nb1;
 } ggml_metal_kargs_conv_transpose_1d;
 
+typedef struct {
+    int32_t  T_in;
+    int32_t  T_out;
+    int32_t  OC;
+    int32_t  K;
+    int32_t  K_OC;
+    int32_t  s0;
+    int32_t  p0;
+} ggml_metal_kargs_col2im_1d;
+
 typedef struct {
     int32_t  IC;
     int32_t  IH;

ggml/src/ggml-metal/ggml-metal-ops.cpp

@@ -395,6 +395,10 @@ static int ggml_metal_op_encode_impl(ggml_metal_op_t ctx, int idx) {
             {
                 n_fuse = ggml_metal_op_conv_transpose_2d(ctx, idx);
             } break;
+        case GGML_OP_COL2IM_1D:
+            {
+                n_fuse = ggml_metal_op_col2im_1d(ctx, idx);
+            } break;
         case GGML_OP_CONV_3D:
             {
                 n_fuse = ggml_metal_op_conv_3d(ctx, idx);
@@ -3854,6 +3858,47 @@ int ggml_metal_op_conv_transpose_1d(ggml_metal_op_t ctx, int idx) {
     return 1;
 }
 
+int ggml_metal_op_col2im_1d(ggml_metal_op_t ctx, int idx) {
+    ggml_tensor * op = ctx->node(idx);
+
+    ggml_metal_library_t lib = ctx->lib;
+    ggml_metal_encoder_t enc = ctx->enc;
+
+    const int32_t s0 = ((const int32_t *)(op->op_params))[0];
+    const int32_t OC = ((const int32_t *)(op->op_params))[1];
+    const int32_t p0 = ((const int32_t *)(op->op_params))[2];
+
+    const int32_t K_OC  = (int32_t) op->src[0]->ne[0];
+    const int32_t T_in  = (int32_t) op->src[0]->ne[1];
+    const int32_t K     = K_OC / OC;
+    const int32_t T_out = (int32_t) op->ne[0];
+
+    ggml_metal_kargs_col2im_1d args = {
+        /*.T_in  =*/ T_in,
+        /*.T_out =*/ T_out,
+        /*.OC    =*/ OC,
+        /*.K     =*/ K,
+        /*.K_OC  =*/ K_OC,
+        /*.s0    =*/ s0,
+        /*.p0    =*/ p0,
+    };
+
+    auto pipeline = ggml_metal_library_get_pipeline_col2im_1d(lib, op);
+
+    const int total = T_out * OC;
+    const int nth   = 256;
+    const int ntg   = (total + nth - 1) / nth;
+
+    ggml_metal_encoder_set_pipeline(enc, pipeline);
+    ggml_metal_encoder_set_bytes   (enc, &args, sizeof(args), 0);
+    ggml_metal_encoder_set_buffer  (enc, ggml_metal_get_buffer_id(op->src[0]), 1);
+    ggml_metal_encoder_set_buffer  (enc, ggml_metal_get_buffer_id(op),         2);
+
+    ggml_metal_encoder_dispatch_threadgroups(enc, ntg, 1, 1, nth, 1, 1);
+
+    return 1;
+}
+
 int ggml_metal_op_conv_transpose_2d(ggml_metal_op_t ctx, int idx) {
     ggml_tensor * op = ctx->node(idx);
 

ggml/src/ggml-metal/ggml-metal-ops.h

@@ -78,6 +78,7 @@ int ggml_metal_op_conv_2d           (ggml_metal_op_t ctx, int idx);
 int ggml_metal_op_conv_3d           (ggml_metal_op_t ctx, int idx);
 int ggml_metal_op_conv_transpose_1d (ggml_metal_op_t ctx, int idx);
 int ggml_metal_op_conv_transpose_2d (ggml_metal_op_t ctx, int idx);
+int ggml_metal_op_col2im_1d         (ggml_metal_op_t ctx, int idx);
 int ggml_metal_op_upscale           (ggml_metal_op_t ctx, int idx);
 int ggml_metal_op_pad               (ggml_metal_op_t ctx, int idx);
 int ggml_metal_op_pad_reflect_1d    (ggml_metal_op_t ctx, int idx);

ggml/src/ggml-metal/ggml-metal.metal

@@ -4977,6 +4977,49 @@ kernel void kernel_conv_transpose_1d<half>(
     uint3    tgpg[[threadgroups_per_grid]]);
 
 
+template <typename T>
+kernel void kernel_col2im_1d(
+        constant ggml_metal_kargs_col2im_1d & args,
+        device const T * col,
+        device       T * dst,
+        uint         tgpig [[threadgroup_position_in_grid]],
+        uint         tpitg [[thread_position_in_threadgroup]],
+        uint         ntg   [[threads_per_threadgroup]]) {
+
+    const int idx = tgpig * ntg + tpitg;
+    if (idx >= args.T_out * args.OC) {
+        return;
+    }
+
+    const int t_out = idx % args.T_out;
+    const int oc    = idx / args.T_out;
+    const int t_abs = t_out + args.p0;  // absolute position in uncropped signal
+
+    int t_in_min = (t_abs - args.K + args.s0) / args.s0;  // ceil((t_abs - K + 1) / s0)
+    if (t_in_min < 0) {
+        t_in_min = 0;
+    }
+    int t_in_max = t_abs / args.s0;
+    if (t_in_max >= args.T_in) {
+        t_in_max = args.T_in - 1;
+    }
+
+    float sum = 0.0f;
+    for (int t_in = t_in_min; t_in <= t_in_max; t_in++) {
+        const int k = t_abs - t_in * args.s0;
+        sum += float(col[(oc * args.K + k) + t_in * args.K_OC]);
+    }
+
+    dst[t_out + oc * args.T_out] = T(sum);
+}
+
+template [[host_name("kernel_col2im_1d_f32")]]  kernel void kernel_col2im_1d<float>(constant ggml_metal_kargs_col2im_1d &, device const float *, device float *, uint, uint, uint);
+template [[host_name("kernel_col2im_1d_f16")]]  kernel void kernel_col2im_1d<half>(constant ggml_metal_kargs_col2im_1d &, device const half *, device half *, uint, uint, uint);
+#if defined(GGML_METAL_HAS_BF16)
+template [[host_name("kernel_col2im_1d_bf16")]] kernel void kernel_col2im_1d<bfloat>(constant ggml_metal_kargs_col2im_1d &, device const bfloat *, device bfloat *, uint, uint, uint);
+#endif
+
+
 typedef void (conv_transpose_2d_t)(
         constant ggml_metal_kargs_conv_transpose_2d & args,
         device const float * src0,