Pointer layout support (#2930)

* WIP looking at reflection with pointers.

* Added GetPointerLayout.

* Initial test via reflection with layout of ptr type.

* WIP handles ptrs to types that have layout that hasn't been completed.

* Move tests to ptr.

* WIP try to take into account lowering correctly between AggTypeDecl and Type, but doesn't quite work.

* WIP a different path to handling recursive lowering problem with Ptr.

* Fix issues with reflection output.

* Small tidy.

* Fix for infinite recursion issue.

* Lower IRPointerTypeLayout

* Working with generics.
Has a hack to work around Layout around Ptr in IR.
The reflection around the generic - the name isn't much use, it should probably have the generic parameters, but that would require getName to do something more sophisticated.

* Fix issue around calling finishOuterGenerics to early.

* Remove feature/ptr test.

* Fix type legalization being an infinite loop with Ptr self referencing.

* Disable the pointer self reference test because produces an infintie loop on emit.

* Fixed comment based on review.

* Fix for issue with emit and pointers causing infinite recursion.

1 files changed, 37 insertions, 0 deletions

diff --git a/tests/language-feature/pointer/pointer-self-reference.slang b/tests/language-feature/pointer/pointer-self-reference.slang
new file mode 100644
index 000000000..e78b70db0
--- /dev/null
+++ b/tests/language-feature/pointer/pointer-self-reference.slang
@@ -0,0 +1,37 @@
+// pointer-self-reference.slang
+
+//TEST(compute):COMPARE_COMPUTE_EX:-cpu -compute -output-using-type -shaderobj
+
+//TEST_INPUT:ubuffer(data=[0 0 0 0], stride=4):out,name=outputBuffer
+RWStructuredBuffer<int> outputBuffer;
+
+struct Thing
+{
+    int value;
+    Ptr<Thing> next;
+};
+
+[numthreads(4, 1, 1)]
+void computeMain(int3 dispatchThreadID: SV_DispatchThreadID)
+{
+    int idx = dispatchThreadID.x;
+    
+    Thing things[2];
+    
+    things[0].next = &things[1];
+    things[0].value = 27;
+    
+    things[1].next = &things[0];
+    things[1].value = idx * idx;
+    
+    Ptr<Thing> cur = &things[0];
+    
+    for (int i = 0; cur && i < idx; ++i)
+    {
+        cur = cur.next;
+    }
+    
+    int v = cur.value;
+    
+    outputBuffer[idx] = v; 
+}