[ExecuTorch][WebGPU] Port pixel_shuffle

backends/webgpu/runtime/ops/pixel_shuffle/PixelShuffle.cpp

@@ -0,0 +1,218 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#include <executorch/backends/webgpu/runtime/WebGPUGraph.h>
+#include <executorch/backends/webgpu/runtime/WebGPUUtils.h>
+#include <executorch/backends/webgpu/runtime/ops/OperatorRegistry.h>
+#include <executorch/backends/webgpu/runtime/ops/pixel_shuffle/pixel_shuffle_wgsl.h>
+
+#include <webgpu/webgpu.h>
+
+#include <cstdint>
+#include <stdexcept>
+#include <vector>
+
+namespace executorch::backends::webgpu {
+
+namespace {
+
+struct PixelShuffleParams {
+  uint32_t r;
+  uint32_t out_c;
+  uint32_t out_h;
+  uint32_t out_w;
+  uint32_t in_c;
+  uint32_t in_h;
+  uint32_t in_w;
+  uint32_t numel;
+};
+static_assert(
+    sizeof(PixelShuffleParams) == 32,
+    "PixelShuffleParams must match the WGSL Params struct (32 bytes)");
+
+// pixel_shuffle: (N,C*r*r,H,W)->(N,C,H*r,W*r) rearrange (Vulkan glsl).
+void pixel_shuffle_impl(WebGPUGraph& graph, const std::vector<int>& args) {
+  // args: [self, upscale_factor, out].
+  const int in_id = args.at(0);
+  const int r_id = args.at(1);
+  const int out_id = args.at(args.size() - 1);
+
+  if (graph.get_value_type(in_id) != WebGPUGraph::ValueType::Tensor ||
+      graph.get_value_type(out_id) != WebGPUGraph::ValueType::Tensor) {
+    throw std::runtime_error("pixel_shuffle: in/out arg is not a tensor");
+  }
+
+  WGPUDevice device = graph.device();
+  const auto& in_tensor = graph.get_tensor(in_id);
+  const auto& out_tensor = graph.get_tensor(out_id);
+  const size_t ndim = in_tensor.dims.size();
+  if (ndim < 3 || out_tensor.dims.size() != ndim) {
+    throw std::runtime_error("pixel_shuffle: expected matching rank >= 3");
+  }
+
+  const int64_t r = graph.get_int(r_id);
+  if (r < 1) {
+    throw std::runtime_error("pixel_shuffle: upscale_factor must be >= 1");
+  }
+
+  // C/H/W are the last 3 dims; any leading dims collapse into the batch.
+  const uint32_t in_c = static_cast<uint32_t>(in_tensor.dims.at(ndim - 3));
+  const uint32_t in_h = static_cast<uint32_t>(in_tensor.dims.at(ndim - 2));
+  const uint32_t in_w = static_cast<uint32_t>(in_tensor.dims.at(ndim - 1));
+  const uint32_t out_c = static_cast<uint32_t>(out_tensor.dims.at(ndim - 3));
+  const uint32_t out_h = static_cast<uint32_t>(out_tensor.dims.at(ndim - 2));
+  const uint32_t out_w = static_cast<uint32_t>(out_tensor.dims.at(ndim - 1));
+  // Mirror Vulkan VK_CHECK_COND(in_sizes[ndim-3] % (r*r) == 0).
+  if (in_c % (static_cast<uint32_t>(r) * static_cast<uint32_t>(r)) != 0) {
+    throw std::runtime_error("pixel_shuffle: in channels not divisible by r*r");
+  }
+
+  uint64_t out_numel = 1;
+  for (int64_t d : out_tensor.dims) {
+    out_numel *= static_cast<uint64_t>(d);
+  }
+  if (in_tensor.nbytes % sizeof(float) != 0 ||
+      out_tensor.nbytes != out_numel * sizeof(float)) {
+    throw std::runtime_error("pixel_shuffle: non-4-byte operand (nbytes % 4)");
+  }
+
+  PixelShuffleParams params = {};
+  params.r = static_cast<uint32_t>(r);
+  params.out_c = out_c;
+  params.out_h = out_h;
+  params.out_w = out_w;
+  params.in_c = in_c;
+  params.in_h = in_h;
+  params.in_w = in_w;
+  params.numel = static_cast<uint32_t>(out_numel);
+
+  uint32_t wg_size =
+      utils::clamp_workgroup_size(device, kPixelShuffleWorkgroupSizeX);
+  utils::WgCount workgroup_count = utils::compute_2d_workgroup_count(
+      device, static_cast<uint32_t>(out_numel), wg_size, "pixel_shuffle");
+
+  WGPUConstantEntry wg_size_constant = {};
+  wg_size_constant.key = {"wg_size", WGPU_STRLEN};
+  wg_size_constant.value = static_cast<double>(wg_size);
+
+  WGPUBuffer params_buf =
+      utils::make_uniform(device, &params, sizeof(PixelShuffleParams));
+  graph.add_uniform_buffer_bytes(sizeof(PixelShuffleParams));
+
+  WGPUShaderSourceWGSL wgsl_desc = {};
+  wgsl_desc.chain.sType = WGPUSType_ShaderSourceWGSL;
+  wgsl_desc.code = {kPixelShuffleWGSL, WGPU_STRLEN};
+  WGPUShaderModuleDescriptor shader_desc = {};
+  shader_desc.nextInChain = &wgsl_desc.chain;
+  WGPUShaderModule shader = wgpuDeviceCreateShaderModule(device, &shader_desc);
+
+  WGPUBindGroupLayoutEntry entries[3] = {};
+  entries[0].binding = 0;
+  entries[0].visibility = WGPUShaderStage_Compute;
+  entries[0].buffer.type = WGPUBufferBindingType_ReadOnlyStorage;
+  entries[1].binding = 1;
+  entries[1].visibility = WGPUShaderStage_Compute;
+  entries[1].buffer.type = WGPUBufferBindingType_Storage;
+  entries[2].binding = 2;
+  entries[2].visibility = WGPUShaderStage_Compute;
+  entries[2].buffer.type = WGPUBufferBindingType_Uniform;
+
+  WGPUBindGroupLayoutDescriptor bgl_desc = {};
+  bgl_desc.entryCount = 3;
+  bgl_desc.entries = entries;
+  WGPUBindGroupLayout bgl = wgpuDeviceCreateBindGroupLayout(device, &bgl_desc);
+
+  WGPUPipelineLayoutDescriptor pl_desc = {};
+  pl_desc.bindGroupLayoutCount = 1;
+  pl_desc.bindGroupLayouts = &bgl;
+  WGPUPipelineLayout pipeline_layout =
+      wgpuDeviceCreatePipelineLayout(device, &pl_desc);
+
+  WGPUComputePipelineDescriptor pipeline_desc = {};
+  pipeline_desc.layout = pipeline_layout;
+  pipeline_desc.compute.module = shader;
+  pipeline_desc.compute.entryPoint = {"main", WGPU_STRLEN};
+  pipeline_desc.compute.constantCount = 1;
+  pipeline_desc.compute.constants = &wg_size_constant;
+  WGPUComputePipeline pipeline =
+      wgpuDeviceCreateComputePipeline(device, &pipeline_desc);
+
+  WGPUBindGroupEntry bg_entries[3] = {};
+  bg_entries[0].binding = 0;
+  bg_entries[0].buffer = in_tensor.buffer;
+  bg_entries[0].size = in_tensor.nbytes;
+  bg_entries[1].binding = 1;
+  bg_entries[1].buffer = out_tensor.buffer;
+  bg_entries[1].size = out_tensor.nbytes;
+  bg_entries[2].binding = 2;
+  bg_entries[2].buffer = params_buf;
+  bg_entries[2].size = sizeof(PixelShuffleParams);
+
+  WGPUBindGroupDescriptor bg_desc = {};
+  bg_desc.layout = bgl;
+  bg_desc.entryCount = 3;
+  bg_desc.entries = bg_entries;
+  WGPUBindGroup bind_group = wgpuDeviceCreateBindGroup(device, &bg_desc);
+
+  const size_t dispatch_idx = graph.add_dispatch(
+      {pipeline,
+       bind_group,
+       workgroup_count.x,
+       "pixel_shuffle",
+       workgroup_count.y});
+
+  // Dynamic shapes: out = in last-3 rescaled by r; recompute params+dispatch.
+  const uint32_t r_u = static_cast<uint32_t>(r);
+  WGPUBuffer p_buf = params_buf;
+  graph.add_tensor_resize_hook(
+      in_id,
+      [in_id, out_id, r_u, wg_size, dispatch_idx, p_buf](WebGPUGraph& g) {
+        const auto& d = g.cur_dims(in_id);
+        const size_t nd = d.size();
+        if (nd < 3) {
+          throw std::runtime_error("pixel_shuffle(resize): rank < 3");
+        }
+        PixelShuffleParams p = {};
+        p.r = r_u;
+        p.in_c = static_cast<uint32_t>(d[nd - 3]);
+        p.in_h = static_cast<uint32_t>(d[nd - 2]);
+        p.in_w = static_cast<uint32_t>(d[nd - 1]);
+        p.out_c = p.in_c / (r_u * r_u);
+        p.out_h = p.in_h * r_u;
+        p.out_w = p.in_w * r_u;
+        std::vector<int64_t> out_d(d);
+        out_d[nd - 3] = p.out_c;
+        out_d[nd - 2] = p.out_h;
+        out_d[nd - 1] = p.out_w;
+        uint64_t n = 1;
+        for (int64_t v : out_d) {
+          n *= static_cast<uint64_t>(v);
+        }
+        p.numel = static_cast<uint32_t>(n);
+        wgpuQueueWriteBuffer(g.queue(), p_buf, 0, &p, sizeof(p));
+        const utils::WgCount wgc = utils::compute_2d_workgroup_count(
+            g.device(), p.numel, wg_size, "pixel_shuffle(resize)");
+        g.dispatch_at(dispatch_idx).workgroup_count_x = wgc.x;
+        g.dispatch_at(dispatch_idx).workgroup_count_y = wgc.y;
+        g.set_cur_dims(out_id, out_d);
+      });
+
+  wgpuShaderModuleRelease(shader);
+  wgpuBindGroupLayoutRelease(bgl);
+  wgpuPipelineLayoutRelease(pipeline_layout);
+  // Graph owns it so the resize hook can rewrite it; freed in the dtor.
+  graph.own_uniform_buffer(params_buf);
+}
+
+} // namespace
+
+WEBGPU_REGISTER_OPERATORS {
+  WEBGPU_REGISTER_OP(aten.pixel_shuffle.default, pixel_shuffle_impl);
+}
+
+} // namespace executorch::backends::webgpu

backends/webgpu/runtime/ops/pixel_shuffle/pixel_shuffle.wgsl

@@ -0,0 +1,42 @@
+@group(0) @binding(0) var<storage, read> input: array<f32>;
+@group(0) @binding(1) var<storage, read_write> output: array<f32>;
+
+struct Params {
+  r: u32,
+  out_c: u32,
+  out_h: u32,
+  out_w: u32,
+  in_c: u32,
+  in_h: u32,
+  in_w: u32,
+  numel: u32,
+}
+@group(0) @binding(2) var<uniform> params: Params;
+
+override wg_size: u32 = 64u;
+
+@compute @workgroup_size(wg_size, 1, 1)
+fn main(
+    @builtin(global_invocation_id) gid: vec3<u32>,
+    @builtin(num_workgroups) num_workgroups: vec3<u32>) {
+    // 2D-folded flat index (lifts the 65535 1D-dispatch cap for large numel).
+    let oi = gid.x + gid.y * (num_workgroups.x * wg_size);
+    if (oi >= params.numel) {
+        return;
+    }
+
+    // (N, C*r*r, H, W) -> (N, C, H*r, W*r); leading dims collapse into b.
+    let w_out = oi % params.out_w;
+    let h_out = (oi / params.out_w) % params.out_h;
+    let c_out = (oi / (params.out_w * params.out_h)) % params.out_c;
+    let b = oi / (params.out_w * params.out_h * params.out_c);
+
+    let w_in = w_out / params.r;
+    let h_in = h_out / params.r;
+    let c_in = c_out * params.r * params.r
+        + (h_out % params.r) * params.r + (w_out % params.r);
+
+    let in_bufi =
+        ((b * params.in_c + c_in) * params.in_h + h_in) * params.in_w + w_in;
+    output[oi] = input[in_bufi];
+}

backends/webgpu/runtime/ops/pixel_shuffle/pixel_shuffle_wgsl.h

@@ -0,0 +1,66 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#pragma once
+
+#include <cstdint>
+
+namespace executorch::backends::webgpu {
+
+// @generated from pixel_shuffle.wgsl - DO NOT EDIT.
+// wgsl-sha256: fc5271241b55091b4989aafec77221ed93115d69b402f46615713339765d91ee
+inline constexpr const char* kPixelShuffleWGSL = R"(
+@group(0) @binding(0) var<storage, read> input: array<f32>;
+@group(0) @binding(1) var<storage, read_write> output: array<f32>;
+
+struct Params {
+  r: u32,
+  out_c: u32,
+  out_h: u32,
+  out_w: u32,
+  in_c: u32,
+  in_h: u32,
+  in_w: u32,
+  numel: u32,
+}
+@group(0) @binding(2) var<uniform> params: Params;
+
+override wg_size: u32 = 64u;
+
+@compute @workgroup_size(wg_size, 1, 1)
+fn main(
+    @builtin(global_invocation_id) gid: vec3<u32>,
+    @builtin(num_workgroups) num_workgroups: vec3<u32>) {
+    // 2D-folded flat index (lifts the 65535 1D-dispatch cap for large numel).
+    let oi = gid.x + gid.y * (num_workgroups.x * wg_size);
+    if (oi >= params.numel) {
+        return;
+    }
+
+    // (N, C*r*r, H, W) -> (N, C, H*r, W*r); leading dims collapse into b.
+    let w_out = oi % params.out_w;
+    let h_out = (oi / params.out_w) % params.out_h;
+    let c_out = (oi / (params.out_w * params.out_h)) % params.out_c;
+    let b = oi / (params.out_w * params.out_h * params.out_c);
+
+    let w_in = w_out / params.r;
+    let h_in = h_out / params.r;
+    let c_in = c_out * params.r * params.r
+        + (h_out % params.r) * params.r + (w_out % params.r);
+
+    let in_bufi =
+        ((b * params.in_c + c_in) * params.in_h + h_in) * params.in_w + w_in;
+    output[oi] = input[in_bufi];
+}
+)";
+
+inline constexpr uint32_t kPixelShuffleWorkgroupSizeX = 64;
+inline constexpr uint32_t kPixelShuffleWorkgroupSizeY = 1;
+inline constexpr uint32_t kPixelShuffleWorkgroupSizeZ = 1;
+
+} // namespace executorch::backends::webgpu