[ET-VK] Introduce generalized shaders for transfer ops and use it for select and slice (#11304)

## Changes

* Introduce `transfer_buffer.glsl` and `transfer_texture.glsl`, and `Transfer.cpp` which generalizes shaders where each element of the output is copied from a unique element of the input.
* Update `Slice.cpp` and `Select.cpp` to use `Transfer.cpp`
* Remove old implementations of slice and select

## Motivation

With this new implementation, the op can now support both buffers and textures of any packing. There are also benefits of code consolidation.

Differential Revision: [D75686050](https://our.internmc.facebook.com/intern/diff/D75686050/)

Author: pytorchbot

backends/vulkan/runtime/graph/ComputeGraph.cpp

@@ -492,14 +492,24 @@ vkapi::BufferBindInfo ComputeGraph::get_or_create_int_param_buffer(
     const ValueRef idx) {
   if (values_.at(idx).isInt()) {
     const int32_t val = extract_scalar<int32_t>(idx);
-    create_params_buffer(val);
+    return create_params_buffer(val);
   } else if (values_.at(idx).isSymInt()) {
     SymIntPtr symint = get_symint(idx);
     return vkapi::BufferBindInfo(symint->gpu_buffer.buffer());
   }
   VK_THROW("Cannot create a int param buffer for the given value");
 }
 
+vkapi::BufferBindInfo ComputeGraph::get_or_create_int_param_buffer(
+    const ValueRef idx,
+    const int32_t default_val) {
+  if (values_.at(idx).isNone()) {
+    return create_params_buffer(default_val);
+  } else {
+    return get_or_create_int_param_buffer(idx);
+  }
+}
+
 void ComputeGraph::set_symint(const ValueRef idx, const int32_t val) {
   get_symint(idx)->set(val);
 }
@@ -693,6 +703,12 @@ void ComputeGraph::resize_input(
   get_tensor(io_val.value)->virtual_resize(new_sizes);
 }
 
+void ComputeGraph::virtual_resize(
+    const ValueRef idx,
+    const std::vector<int64_t>& new_sizes) {
+  get_tensor(idx)->virtual_resize(new_sizes);
+}
+
 void ComputeGraph::propagate_resize() {
   for (std::unique_ptr<ExecuteNode>& node : execute_nodes_) {
     node->trigger_resize(this);

backends/vulkan/runtime/graph/ComputeGraph.h

@@ -398,6 +398,19 @@ class ComputeGraph final {
   std::optional<T> extract_optional_scalar(const ValueRef idx) {
     if (val_is_none(idx)) {
       return ::std::nullopt;
+    } else if (val_is_symint(idx)) {
+      return utils::safe_downcast<T>(read_symint(idx));
+    } else {
+      return extract_scalar<T>(idx);
+    }
+  }
+
+  template <typename T>
+  T extract_optional_scalar(const ValueRef idx, const T default_val) {
+    if (val_is_none(idx)) {
+      return default_val;
+    } else if (val_is_symint(idx)) {
+      return utils::safe_downcast<T>(read_symint(idx));
     } else {
       return extract_scalar<T>(idx);
     }
@@ -609,6 +622,10 @@ class ComputeGraph final {
    */
   vkapi::BufferBindInfo get_or_create_int_param_buffer(const ValueRef idx);
 
+  vkapi::BufferBindInfo get_or_create_int_param_buffer(
+      const ValueRef idx,
+      const int32_t default_value);
+
   void set_symint(const ValueRef idx, const int32_t val);
 
   int32_t read_symint(const ValueRef idx);
@@ -753,6 +770,9 @@ class ComputeGraph final {
   //
 
   void resize_input(const int64_t idx, const std::vector<int64_t>& new_sizes);
+  void virtual_resize(
+      const ValueRef idx,
+      const std::vector<int64_t>& new_sizes);
   void propagate_resize();
 
   //

backends/vulkan/runtime/graph/ops/glsl/select.glslh

@@ -0,0 +1,74 @@
+/*
+ * 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.
+ */
+
+#ifndef SELECT_GLSLH
+#define SELECT_GLSLH
+
+/*
+ * Enable the fast path if a texel loaded from the input texture can be used as
+ * is to store to the output texture. The following conditions must be met:
+ *
+ * 1. The input and output textures have the same packed dimension.
+ * 2. The selected_dim must not be the packed dimension of the input.
+ * 3. The packed dimension of the input must "map" to the packed dimension of
+ *    the output. This occurs if selected_dim is greater than the packed dimension
+ *    of the input.
+ */
+bool can_use_fast_path() {
+  if (out_packed_dim != in_packed_dim) {
+    return false;
+  }
+  if (selected_dim <= in_packed_dim) {
+    return false;
+  }
+  return true;
+}
+
+/*
+ * Given an output tensor index, return the corresponding input tensor index for
+ * the select operator. This is done by "inserting" the select index at the
+ * selected_dim in the input tensor index.
+ *
+ * A simple example is (note all tensor index are in WHCN order):
+ *   out_tidx = [7, 5, 9]
+ *   selected_dim = 2
+ *   index = 3
+ *   in_tidx = [7, 3, 5, 9]
+ *
+ * This function assumes that the following variables are defined in the layout:
+ * - in_sizes
+ * - selected_dim
+ * - index
+ */
+ivec4 out_tidx_to_in_tidx(const ivec4 out_tidx) {
+  ivec4 in_tidx = ivec4(0);
+
+  int adjusted_index = index;
+  if (index < 0) {
+    adjusted_index = index + in_sizes[selected_dim];
+  }
+
+  // Handle different dimensions for selection
+  if (selected_dim == 0) {
+    // Select from width dimension
+    in_tidx = ivec4(adjusted_index, out_tidx.x, out_tidx.y, out_tidx.z);
+  } else if (selected_dim == 1) {
+    // Select from height dimension
+    in_tidx = ivec4(out_tidx.x, adjusted_index, out_tidx.y, out_tidx.z);
+  } else if (selected_dim == 2) {
+    // Select from channel dimension
+    in_tidx = ivec4(out_tidx.x, out_tidx.y, adjusted_index, out_tidx.z);
+  } else if (selected_dim == 3) {
+    // Select from batch dimension
+    in_tidx = ivec4(out_tidx.x, out_tidx.y, out_tidx.z, adjusted_index);
+  }
+
+  return in_tidx;
+}
+
+#endif // SELECT_GLSLH