Improve compile time performance. (#3857)

* Handle type check cache update on extensions more gracefully.

* Correctness fix.

* Cache implcit cast overload resolution results.

* Fix.

* More optimizations.

* Cache implicit default ctor resolution.

* Disable redundancy removal.

* Fix.

* Fix test.

* Fix.

* Correctness fix.

* Fix.

* Fix,

* Fix test.

* Small tweak.

1 files changed, 30 insertions, 0 deletions

diff --git a/tests/language-feature/extensions/extension-method-simple.slang b/tests/language-feature/extensions/extension-method-simple.slang
new file mode 100644
index 000000000..d3162c053
--- /dev/null
+++ b/tests/language-feature/extensions/extension-method-simple.slang
@@ -0,0 +1,30 @@
+// interface-extension.slang
+
+// Test that an `extension` applied to an interface type works as users expect
+
+//TEST(compute):COMPARE_COMPUTE(filecheck-buffer=CHECK): -shaderobj
+
+struct MyType
+{
+    int v;
+}
+
+extension MyType
+{
+    int foo()
+    {
+        return v;
+    }
+}
+
+//TEST_INPUT:ubuffer(data=[0 0 0 0], stride=4):out,name=outputBuffer
+RWStructuredBuffer<int> outputBuffer;
+
+[numthreads(4, 1, 1)]
+void computeMain(int3 dispatchThreadID : SV_DispatchThreadID)
+{
+    MyType t;
+    t.v = 1;
+    // CHECK: 1
+    outputBuffer[dispatchThreadID.x] = t.foo();
+}