Initial implementation of SP#015 `DescriptorHandle<T>`. (#6028)

* Initial implementation of `ResourcePtr<T>`.

* Update docs

* Fix build error.

* Add more discussion.

* Update documentation.

* Update TOC.

* Fix.

* Fix.

* Add test case for custom `getResourceFromBindlessHandle`.

* Add namehint to generated descriptor heap param.

* Fix.

* Fix.

* format code

* Rename to `DescriptorHandle`, and add `T.Handle` alias.

* Fix compiler error.

* Fix.

* Fix build.

* Renames.

* Fix documentation.

* Documentation fix.

---------

Co-authored-by: slangbot <186143334+slangbot@users.noreply.github.com>

4 files changed, 103 insertions, 0 deletions

diff --git a/tests/language-feature/descriptor-handle/desc-handle-0.slang b/tests/language-feature/descriptor-handle/desc-handle-0.slang
new file mode 100644
index 000000000..67f452cfc
--- /dev/null
+++ b/tests/language-feature/descriptor-handle/desc-handle-0.slang
@@ -0,0 +1,22 @@
+//TEST:SIMPLE(filecheck=CUDA): -target cuda -entry computeMain -stage compute
+//TEST:SIMPLE(filecheck=MTL): -target metallib -entry computeMain -profile cs_6_6
+//TEST:SIMPLE(filecheck=HLSL): -target hlsl -entry computeMain -profile cs_6_6
+//TEST:SIMPLE(filecheck=DXIL): -target dxil -entry computeMain -profile cs_6_6
+//TEST:SIMPLE(filecheck=SPV): -target spirv
+
+// SPV: OpImageSample
+// HLSL: ResourceDescriptorHeap[{{.*}}]
+// HLSL: SamplerDescriptorHeap[{{.*}}]
+// HLSL: SampleLevel
+// DXIL: computeMain
+// CUDA: computeMain
+// MTL: define void @computeMain
+
+uniform StructuredBuffer<DescriptorHandle<Sampler2D>> t;
+uniform DescriptorHandle<RWStructuredBuffer<float4>> buffer;
+
+[numthreads(1,1,1)]
+void computeMain()
+{
+    buffer[0] = t[0]->SampleLevel(float2(0.0), 0.0);
+}
\ No newline at end of file
diff --git a/tests/language-feature/descriptor-handle/desc-handle-1.slang b/tests/language-feature/descriptor-handle/desc-handle-1.slang
new file mode 100644
index 000000000..0621f4a84
--- /dev/null
+++ b/tests/language-feature/descriptor-handle/desc-handle-1.slang
@@ -0,0 +1,32 @@
+//TEST:SIMPLE(filecheck=SPV): -target spirv
+
+// SPV: OpDecorate %resourceHeap DescriptorSet 10
+// SPV: OpAccessChain {{.*}} %resourceHeap
+// SPV: OpImageSample
+
+uniform StructuredBuffer<DescriptorHandle<Sampler2D>> t;
+uniform DescriptorHandle<RWStructuredBuffer<float4>> buffer;
+
+[vk::binding(0, 10)]
+__DynamicResource<__DynamicResourceKind.General> resourceHeap[]; 
+
+// A customized function that overrides the default behavior of fetch texture resources.
+export T getDescriptorFromHandle<T:IOpaqueDescriptor>(DescriptorHandle<T> handleValue)
+{
+    __target_switch
+    {
+    case spirv:
+        if (T.kind != DescriptorKind.Buffer)
+            return resourceHeap[((uint2)handleValue).x].asOpaqueDescriptor<T>();
+        else
+            return defaultGetDescriptorFromHandle(handleValue);
+    default:
+        return defaultGetDescriptorFromHandle(handleValue);
+    }
+}
+
+[numthreads(1,1,1)]
+void computeMain()
+{
+    buffer[0] = t[0]->SampleLevel(float2(0.0), 0.0);
+}
\ No newline at end of file
diff --git a/tests/language-feature/descriptor-handle/desc-handle-2.slang b/tests/language-feature/descriptor-handle/desc-handle-2.slang
new file mode 100644
index 000000000..fa7f73b31
--- /dev/null
+++ b/tests/language-feature/descriptor-handle/desc-handle-2.slang
@@ -0,0 +1,14 @@
+//TEST:SIMPLE(filecheck=SPV): -target spirv -bindless-space-index 101
+
+// SPV: OpDecorate %__slang_resource_heap{{.*}} Binding 0
+// SPV: OpDecorate %__slang_resource_heap{{.*}} DescriptorSet 101
+// SPV: OpImageSample
+
+uniform StructuredBuffer<DescriptorHandle<Sampler2D>> t;
+uniform DescriptorHandle<RWStructuredBuffer<float4>> buffer;
+
+[numthreads(1,1,1)]
+void computeMain()
+{
+    (*buffer)[0] = t[0].SampleLevel(float2(0.0), 0.0);
+}
\ No newline at end of file
diff --git a/tests/language-feature/descriptor-handle/desc-handle-3.slang b/tests/language-feature/descriptor-handle/desc-handle-3.slang
new file mode 100644
index 000000000..5b9263026
--- /dev/null
+++ b/tests/language-feature/descriptor-handle/desc-handle-3.slang
@@ -0,0 +1,35 @@
+//TEST:SIMPLE(filecheck=MTL): -target metal
+//TEST:SIMPLE(filecheck=MTLLIB): -target metallib
+//TEST:SIMPLE(filecheck=CUDA): -target cuda -entry computeMain -stage compute
+//TEST:SIMPLE(filecheck=PTX): -target ptx -entry computeMain -stage compute 
+//TEST:SIMPLE(filecheck=SPV): -target spirv -entry computeMain -stage compute -emit-spirv-via-glsl
+//TEST:SIMPLE(filecheck=GLSL): -target glsl -entry computeMain -stage compute
+//TEST:SIMPLE(filecheck=HLSL): -target hlsl -entry computeMain -profile cs_6_6
+//TEST:SIMPLE(filecheck=DXIL): -target dxil -entry computeMain -profile cs_6_6
+//TEST:SIMPLE(filecheck=SPV): -target spirv
+
+// SPV-DAG: %[[REG:[A-Za-z_0-9]+]] = OpAccessChain{{.*}}NonUniform
+// SPV-DAG: %[[TEX:[A-Za-z_0-9]+]] = OpLoad {{.*}} %[[REG]]
+// SPV-DAG: OpImageSampleExplicitLod {{.*}} %[[TEX]]
+
+// HLSL: ResourceDescriptorHeap[NonUniformResourceIndex
+// HLSL: SamplerDescriptorHeap[NonUniformResourceIndex(
+
+// DXIL: define void @computeMain()
+
+// GLSL: _slang_resource_heap{{[0-9_]+}}[nonuniformEXT
+
+// MTL: void computeMain
+// MTLLIB: @computeMain
+
+// CUDA: tex2DLod
+// PTX: computeMain
+
+uniform StructuredBuffer<Sampler2D.Handle> t;
+uniform RWStructuredBuffer<float4>.Handle buffer;
+
+[numthreads(4,1,1)]
+void computeMain(int3 id : SV_DispatchThreadID)
+{
+    (*buffer)[0] = nonuniform(t[id.x]).SampleLevel(float2(0.0), 0.0);
+}
\ No newline at end of file