[clang] Implement resource binding type prefix mismatch diagnostic infrastructure (PR #97103)

[Damyan Pepper via cfe-commits]

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@@ -0,0 +1,103 @@
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-library -x hlsl -o - -fsyntax-only %s -verify
+
+// TODO: Implement "Buffer"
+struct Eg1 {
+  float f;
+  // Buffer<float> Buf;
+  RWBuffer<float> RWBuf;
+  };
+Eg1 e1 : /* register(t0) :*/ register(u0); 
+// Valid: f is skipped, Buf is bound to t0, RWBuf is bound to u0
+
+
+struct Eg2 {
+  float f;
+  // Buffer<float> Buf;
+  RWBuffer<float> RWBuf;
+  RWBuffer<float> RWBuf2;
+  };
+Eg2 e2 : /* register(t0) :*/ register(u0); 
+// Valid: f is skipped, Buf is bound to t0, RWBuf is bound to u0. 
+// RWBuf2 gets automatically assigned to u1 even though there is no explicit binding for u1.
+
+/*
+struct Eg3 {
+  float f;
+  // Buffer<float> Buf;
+  }; 
+Eg3 e3 : register(t0) : register(u0);
+// Valid: Buf gets bound to t0. Buf will also be bound to u0.
+*/
+
+struct Eg4 {
+  struct Bar {
+    RWBuffer<int> a;
+    };
+    Bar b;
+};
+Eg4 e4 : register(u0);
+// Valid: Bar, the struct within Eg4, has a valid resource that can be bound to t0. 
+
+/* Light up this test when SamplerState is implemented
+struct Eg5 {
+  SamplerState s[3];
+};
+
+Eg5 e5 : register(s5);
+// Valid: the first sampler state object within Eg5's s is bound to slot 5
+*/
+
+struct Eg6 {
+  float f;
+}; 
+// expected-warning at +1{{variable of type 'Eg6' bound to register type 't' does not contain a matching 'srv' resource}}
+Eg6 e6 : register(t0);
+
+struct Eg7 {
+  struct Bar {
+    float f;
+  };
+  Bar b;
+};
+// expected-warning at +1{{variable of type 'Eg7' bound to register type 't' does not contain a matching 'srv' resource}}
+Eg7 e7 : register(t0);
+
+struct Eg8 {
+  RWBuffer<int> a;
+}; 
+// expected-warning at +1{{register 'c' used on type with no contents to allocate in a constant buffer}}
+Eg8 e8 : register(c0);
+
+
+struct Eg9{
+  // expected-error at +1{{'register' attribute only applies to cbuffer/tbuffer and external global variables}}
+  RWBuffer<int> a : register(u9);
+};
+
+Eg9 e9;
+/* Light up this test when Texture2D is implemented
+template<typename R>
+struct Eg10 {
+    R b;
+};
+// expecting warning: {{variable of type 'Eg10' bound to register type 'u' does not contain a matching 'uav' resource}}
+Eg10<Texture2D> e10 : register(u0);
+
+// invalid because after template expansion, there are no valid resources inside Eg10 to bind as a UAV.
+*/
+
+struct Eg11{
+  RWBuffer<int> a;
+  RWBuffer<int> b;
+};
+
+// expected-error at +1{{conflicting register annotations: multiple register annotations detected for register type 'u'}}
+Eg11 e11 : register(u9) : register(u10);
+// expected-error at +1{{conflicting register annotations: multiple register annotations detected for register type 'u'}}
+Eg11 e11a : register(u9, space0) : register(u9, space1);
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damyanp wrote:

This is different to DXC - DXC prohibits register space's entirely for globals like this.  Maybe we want to change the language there, but we should do that deliberately if so.

https://github.com/llvm/llvm-project/pull/97103