Fix output of `groupshared` with IR type system (#492)

The basic problem was that the lowering logic was constructing (more or less) `Ptr<@GroupShared X>` instead of `@GroupShared Ptr<X>`.
There were also problems with passes not propagating through rates that should have been (e.g., legalization).

I've added a test case to actually validate `groupshared` support.

1 files changed, 39 insertions, 0 deletions

diff --git a/tests/compute/groupshared.slang b/tests/compute/groupshared.slang
new file mode 100644
index 000000000..e471e6148
--- /dev/null
+++ b/tests/compute/groupshared.slang
@@ -0,0 +1,39 @@
+// groupshared.slang
+
+//TEST(compute):COMPARE_COMPUTE_EX:-slang -compute
+//TEST(compute):COMPARE_COMPUTE_EX:-slang -compute -dx12
+//TEST(compute, vulkan):COMPARE_COMPUTE_EX:-vk -compute
+
+//TEST_INPUT:ubuffer(data=[0 0 0 0], stride=4):dxbinding(0),glbinding(0),out
+
+#define THREAD_COUNT 4
+
+groupshared int gA[THREAD_COUNT];
+int test(int val)
+{
+	gA[val] = val;
+	GroupMemoryBarrierWithGroupSync();
+	val = gA[val ^ 1];
+
+/* TODO: once function-scope `static` works
+	static groupshared int gB[THREAD_COUNT];
+
+	gB[val] = val;
+	GroupMemoryBarrierWithGroupSync();
+	val = gB[val ^ 2];
+*/
+
+	return val;
+}
+
+RWStructuredBuffer<int> gBuffer;
+
+[numthreads(THREAD_COUNT, 1, 1)]
+void computeMain(uint3 dispatchThreadID : SV_DispatchThreadID)
+{
+	uint tid = dispatchThreadID.x;
+
+	int val = int(tid);
+	val = test(val);
+	gBuffer[tid] = val;
+}
\ No newline at end of file