Restructure GPU compilation execution pipeline (#903)

* Restructure gpu compilation execution pipeline

* Add compilation server/client infrastructure

* Add wgpu executor

node-graph/gpu-compiler/src/templates/spirv-template.rs

@@ -0,0 +1,38 @@
+#![no_std]
+#![feature(unchecked_math)]
+#![deny(warnings)]
+
+#[cfg(target_arch = "spirv")]
+extern crate spirv_std;
+
+#[cfg(target_arch = "spirv")]
+pub mod gpu {
+    use super::*;
+    use spirv_std::spirv;
+    use spirv_std::glam::UVec3;
+
+    #[allow(unused)]
+    #[spirv(compute(threads({{compute_threads}})))]
+    pub fn eval (
+        #[spirv(global_invocation_id)] global_id: UVec3,
+        #[spirv(storage_buffer, descriptor_set = 0, binding = 0)] a: &[{{input_type}}],
+        #[spirv(storage_buffer, descriptor_set = 0, binding = 1)] y: &mut [{{output_type}}],
+        #[spirv(push_constant)] push_consts: &graphene_core::gpu::PushConstants,
+    ) {
+        let gid = global_id.x as usize;
+        // Only process up to n, which is the length of the buffers.
+        if global_id.x < push_consts.n {
+            y[gid] = node_graph(a[gid]);
+        }
+    }
+
+    fn node_graph(input: {{input_type}}) -> {{output_type}} {
+        use graphene_core::Node;
+
+        {% for node in nodes %}
+        let {{node.id}} = {{node.fqn}}::new({% for arg in node.args %}{{arg}}, {% endfor %});
+        {% endfor %}
+		{{last_node}}.eval(input)
+    }
+
+}