Add generic descriptor indexing intrinsic (#4389)

* Add ResourceArray intrinsic type

* Move aliased parameter generation to GLSL legalization

* Add DynamicResourceEntry type for proxying layout of GenericResourceArray

* Reimplement as DynamicResource

* Add reflection test

* Don't reuse alias cache between different parameters

* Add dynamic cast extensions for buffer types

* Minor format fix

* Fix VarDecl diagnostics after finding non-appliable initializer candidates

---------

Co-authored-by: Yong He <yonghe@outlook.com>

2 files changed, 154 insertions, 0 deletions

diff --git a/tests/slang-extension/dynamic-resource-gl.slang b/tests/slang-extension/dynamic-resource-gl.slang
new file mode 100644
index 000000000..0ea82dd8f
--- /dev/null
+++ b/tests/slang-extension/dynamic-resource-gl.slang
@@ -0,0 +1,59 @@
+//TEST:SIMPLE(filecheck=CHECK): -stage compute -entry computeMain -target glsl
+//TEST:REFLECTION: -stage compute -entry computeMain -target glsl
+
+// CHECK-DAG: layout(binding = 0, set = 1)
+// CHECK-DAG: texture2D g_TextureHeap_1[]
+
+// CHECK-DAG: layout(binding = 0, set = 1)
+// CHECK-DAG: utexture2D g_TextureHeap_0[]
+
+[vk::binding(0, 1)]
+__DynamicResource<__DynamicResourceKind.General> g_TextureHeap[];
+
+// CHECK-DAG: layout(binding = 2, set = 1)
+// CHECK-DAG: sampler g_SamplerHeap_0[]
+[vk::binding(2, 1)]
+__DynamicResource<__DynamicResourceKind.Sampler> g_SamplerHeap[];
+
+// CHECK-DAG: layout(binding = 0, set = 2)
+// CHECK-DAG: texture2D g_SingleDynamicResourceA_0;
+[vk::binding(0, 2)]
+__DynamicResource g_SingleDynamicResourceA;
+
+// CHECK-DAG: layout(binding = 1, set = 2)
+// CHECK-DAG: texture2D g_SingleDynamicResourceB_0;
+[vk::binding(1, 2)]
+__DynamicResource g_SingleDynamicResourceB;
+
+// CHECK-DAG: layout(std430, binding = 2, set = 2) buffer
+[vk::binding(2, 2)]
+__DynamicResource g_SingleDynamicResourceC;
+
+// CHECK: IndirectAccess_0
+// CHECK: g_TextureHeap_0[_S1]
+[noinline]
+float4 IndirectAccess(__DynamicResource resource, int2 pos)
+{
+    let texture = resource.as<Texture2D<uint4>>();
+    return texture[pos] / 255.0;
+}
+
+// CHECK: main
+// CHECK-DAG: g_TextureHeap_1[3]
+// CHECK-DAG: g_SamplerHeap_0[2]
+[numthreads(16)]
+void computeMain(int2 tid: SV_DispatchThreadID)
+{
+    Texture2D texture = g_TextureHeap[3];
+    SamplerState sampler = g_SamplerHeap[2].as<SamplerState>();
+
+    float4 value = texture.SampleLevel(sampler, tid / 64.0, 0.0);
+
+    value += IndirectAccess(g_TextureHeap[1], tid);
+
+    value += g_SingleDynamicResourceA.as<Texture2D>()[tid];
+    value += g_SingleDynamicResourceB.as<Texture2D>()[tid];
+
+    RWStructuredBuffer<float4> outputBuffer = g_SingleDynamicResourceC;
+    outputBuffer[tid.x + tid.y * 64] = value;
+}
\ No newline at end of file
diff --git a/tests/slang-extension/dynamic-resource-gl.slang.1.expected b/tests/slang-extension/dynamic-resource-gl.slang.1.expected
new file mode 100644
index 000000000..fe48e643a
--- /dev/null
+++ b/tests/slang-extension/dynamic-resource-gl.slang.1.expected
@@ -0,0 +1,95 @@
+result code = 0
+standard error = {
+}
+standard output = {
+{
+    "parameters": [
+        {
+            "name": "g_TextureHeap",
+            "binding": {"kind": "descriptorTableSlot", "space": 1, "index": 0},
+            "type": {
+                "kind": "array",
+                "elementCount": 0,
+                "elementType": {
+                    "kind": "DynamicResource"
+                }
+            }
+        },
+        {
+            "name": "g_SamplerHeap",
+            "binding": {"kind": "descriptorTableSlot", "space": 1, "index": 2},
+            "type": {
+                "kind": "array",
+                "elementCount": 0,
+                "elementType": {
+                    "kind": "DynamicResource"
+                }
+            }
+        },
+        {
+            "name": "g_SingleDynamicResourceA",
+            "binding": {"kind": "descriptorTableSlot", "space": 2, "index": 0},
+            "type": {
+                "kind": "DynamicResource"
+            }
+        },
+        {
+            "name": "g_SingleDynamicResourceB",
+            "binding": {"kind": "descriptorTableSlot", "space": 2, "index": 1},
+            "type": {
+                "kind": "DynamicResource"
+            }
+        },
+        {
+            "name": "g_SingleDynamicResourceC",
+            "binding": {"kind": "descriptorTableSlot", "space": 2, "index": 2},
+            "type": {
+                "kind": "DynamicResource"
+            }
+        }
+    ],
+    "entryPoints": [
+        {
+            "name": "computeMain",
+            "stage:": "compute",
+            "parameters": [
+                {
+                    "name": "tid",
+                    "semanticName": "SV_DISPATCHTHREADID",
+                    "type": {
+                        "kind": "vector",
+                        "elementCount": 2,
+                        "elementType": {
+                            "kind": "scalar",
+                            "scalarType": "int32"
+                        }
+                    }
+                }
+            ],
+            "threadGroupSize": [16, 1, 1],
+            "bindings": [
+                {
+                    "name": "g_TextureHeap",
+                    "binding": {"kind": "descriptorTableSlot", "space": 1, "index": 0}
+                },
+                {
+                    "name": "g_SamplerHeap",
+                    "binding": {"kind": "descriptorTableSlot", "space": 1, "index": 2}
+                },
+                {
+                    "name": "g_SingleDynamicResourceA",
+                    "binding": {"kind": "descriptorTableSlot", "space": 2, "index": 0}
+                },
+                {
+                    "name": "g_SingleDynamicResourceB",
+                    "binding": {"kind": "descriptorTableSlot", "space": 2, "index": 1}
+                },
+                {
+                    "name": "g_SingleDynamicResourceC",
+                    "binding": {"kind": "descriptorTableSlot", "space": 2, "index": 2}
+                }
+            ]
+        }
+    ]
+}
+}