[clang] [HLSL] Add testing for space parameter on global constants (PR #106782)

[Damyan Pepper via cfe-commits]

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@@ -0,0 +1,66 @@
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-library -x hlsl -o - -fsyntax-only %s -verify
+
+// valid
+cbuffer cbuf {
+    RWBuffer<int> r : register(u0, space0);
+}
+
+cbuffer cbuf2 {
+    struct x {
+        // this test validates that no diagnostic is emitted on the space parameter, because
+        // this register annotation is not in the global scope.
+        // expected-error at +1 {{'register' attribute only applies to cbuffer/tbuffer and external global variables}}
+        RWBuffer<int> E : register(u2, space3);
+    };
+}
+
+struct MyStruct {
+    RWBuffer<int> E;
+};
+
+cbuffer cbuf3 {
+  // valid
+  MyStruct E : register(u2, space3);
+}
+
+// valid
+MyStruct F : register(u3, space4);
+
+cbuffer cbuf4 {
+  // this test validates that no diagnostic is emitted on the space parameter, because
+  // this register annotation is not in the global scope.
+  // expected-error at +1 {{binding type 'u' only applies to UAV resources}}
+  float a : register(u2, space3); 
+}
+
+// expected-error at +1 {{invalid space specifier 's2' used; expected 'space' followed by an integer, like space1}}
+cbuffer a : register(b0, s2) {
+
+}
+
+// expected-error at +1 {{invalid space specifier 'spaces' used; expected 'space' followed by an integer, like space1}}
+cbuffer b : register(b2, spaces) {
+
+}
+
+// expected-error at +1 {{wrong argument format for hlsl attribute, use space3 instead}}
+cbuffer c : register(b2, space 3) {}
+
+// expected-error at +1 {{register space cannot be specified on global constants}}
+int d : register(c2, space3);
+
+// expected-error at +1 {{register space cannot be specified on global constants}}
+int e : register(c2, space0);
+
+// expected-error at +1 {{register space cannot be specified on global constants}}
+int f : register(c2, space00);
+
+// valid
+RWBuffer<int> g : register(u2, space0);
+
+// valid
+RWBuffer<int> h : register(u2, space0);
+
+struct S {
+    RWBuffer<int> a;
+};
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damyanp wrote:

What is this for?

https://github.com/llvm/llvm-project/pull/106782