Merge from v0.9.15 (#460)

* Fix bug when subscripting a type that must be split (#396)

The logic was creating a `PairPseudoExpr` as part of a subscript (`operator[]`) operation, but neglecting to fill in its `pairInfo` field, which led to a null-pointer crash further along.

* Allow writes to UAV textures (#416)

Work on #415

This issue is already fixed in the `v0.10.*` line, but I'm back-porting the fix to `v0.9.*`.
The issue here was that the stdlib declarations for texture types were only including the `get` accessor for subscript operations, even if the texture was write-able.

I've also included the fixes for other subscript accessors in the stdlib (notably that `OutputPatch<T>` is readable, but not writable, despite what the name seems to imply).

* Fix infinite loop in semantic parsing (#424)

The code for parsing semantics was looking for a fixed set of tokens to terminate a semantic list, rather than assuming that whenever you don't see a `:` ahead, you probably are done with semantics. This meant that you could get into an infinite loop just with simple mistakes like leaving out a `;`.

This change fixes the parser to note infinite loop in this case, and adds a test case to verify the fix.

* Expose HLSL `shared` modifier through reflection. (#436)

This is a request from Falcor, because the `shared` modifier can be used as a hint to optimize the grouping of parameters for binding. The intention is that `shared` marks shader parameters (including parameter blocks) that will us the same values across many draw calls (e.g., per-frame data, as opposed to per-model or per-instance).

The mechanism I'm using here is to provide a general reflection API for exposing the `Modifier`s already attached to declarations. While the only modifier exposed is `shared`, and the only modifier information being exposed is presence/absence, this interface could be extended down the line.

2 files changed, 59 insertions, 0 deletions

diff --git a/tests/reflection/shared-modifier.hlsl b/tests/reflection/shared-modifier.hlsl
new file mode 100644
index 000000000..45a1dfac8
--- /dev/null
+++ b/tests/reflection/shared-modifier.hlsl
@@ -0,0 +1,12 @@
+// shared-modifier.hlsl
+//TEST:REFLECTION:-profile ps_5_0 -target hlsl
+
+// Confirm that we expose the `shared` modifier in reflection data.
+
+Texture2D t;
+shared SamplerState s;
+
+float4 main(float2 uv : UV) : SV_Target
+{
+	return t.Sample(s, uv);
+}
\ No newline at end of file
diff --git a/tests/reflection/shared-modifier.hlsl.expected b/tests/reflection/shared-modifier.hlsl.expected
new file mode 100644
index 000000000..ddb982177
--- /dev/null
+++ b/tests/reflection/shared-modifier.hlsl.expected
@@ -0,0 +1,47 @@
+result code = 0
+standard error = {
+}
+standard output = {
+{
+    "parameters": [
+        {
+            "name": "t",
+            "binding": {"kind": "shaderResource", "index": 0},
+            "type": {
+                "kind": "resource",
+                "baseShape": "texture2D"
+            }
+        },
+        {
+            "name": "s",
+            "shared": true,
+            "binding": {"kind": "samplerState", "index": 0},
+            "type": {
+                "kind": "samplerState"
+            }
+        }
+    ],
+    "entryPoints": [
+        {
+            "name": "main",
+            "stage:": "fragment",
+            "parameters": [
+                {
+                    "name": "uv",
+                    "stage": "fragment",
+                    "binding": {"kind": "varyingInput", "index": 0},
+                    "semanticName": "UV",
+                    "type": {
+                        "kind": "vector",
+                        "elementCount": 2,
+                        "elementType": {
+                            "kind": "scalar",
+                            "scalarType": "float32"
+                        }
+                    }
+                }
+            ]
+        }
+    ]
+}
+}