[clang] [HLSL] Default and Relaxed Availability Diagnostics (PR #92704)

[Damyan Pepper via cfe-commits]

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@@ -0,0 +1,98 @@
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.0-compute \
+// RUN: -fsyntax-only -verify %s
+
+__attribute__((availability(shadermodel, introduced = 6.5)))
+float fx(float);  // #fx
+
+__attribute__((availability(shadermodel, introduced = 5.0, environment = pixel)))
+__attribute__((availability(shadermodel, introduced = 6.5, environment = compute)))
+float fy(float); // #fy
+
+__attribute__((availability(shadermodel, introduced = 5.0, environment = pixel)))
+__attribute__((availability(shadermodel, introduced = 6.5, environment = mesh)))
+float fz(float); // #fz
+
+float also_alive(float f) {
+  // expected-error@#also_alive_fx_call {{'fx' is only available on Shader Model 6.5 or newer}}
+  // expected-note@#fx {{'fx' has been marked as being introduced in Shader Model 6.5 here, but the deployment target is Shader Model 6.0}}
+  float A = fx(f); // #also_alive_fx_call
+  // expected-error@#also_alive_fy_call {{'fy' is only available in compute shader environment on Shader Model 6.5 or newer}}
+  // expected-note@#fy {{'fy' has been marked as being introduced in Shader Model 6.5 in compute shader environment here, but the deployment target is Shader Model 6.0 compute shader environment}}
+  float B = fy(f); // #also_alive_fy_call
+  // expected-error@#also_alive_fz_call {{'fz' is unavailable}}
+  // expected-note@#fz {{'fz' has been marked as being introduced in Shader Model 6.5 in mesh shader environment here, but the deployment target is Shader Model 6.0 compute shader environment}}
+  float C = fz(f); // #also_alive_fz_call
+  return 0;
+}
+
+float alive(float f) {
+  // expected-error@#alive_fx_call {{'fx' is only available on Shader Model 6.5 or newer}}
+  // expected-note@#fx {{'fx' has been marked as being introduced in Shader Model 6.5 here, but the deployment target is Shader Model 6.0}}
+  float A = fx(f); // #alive_fx_call
+  // expected-error@#alive_fy_call {{'fy' is only available in compute shader environment on Shader Model 6.5 or newer}}
+  // expected-note@#fy {{'fy' has been marked as being introduced in Shader Model 6.5 in compute shader environment here, but the deployment target is Shader Model 6.0 compute shader environment}}
+  float B = fy(f); // #alive_fy_call
+  // expected-error@#alive_fz_call {{'fz' is unavailable}}
+  // expected-note@#fz {{'fz' has been marked as being introduced in Shader Model 6.5 in mesh shader environment here, but the deployment target is Shader Model 6.0 compute shader environment}}
+  float C = fz(f); // #alive_fz_call
+
+  return also_alive(f);
+}
+
+float also_dead(float f) {
+  // unreachable code - no errors expected
+  float A = fx(f);
+  float B = fy(f);
+  float C = fz(f);
+  return 0;
+}
+
+float dead(float f) {
+  // unreachable code - no errors expected
+  float A = fx(f);
+  float B = fy(f);
+  float C = fz(f);
+
+  return also_dead(f);
+}
+
+template<typename T>
+T aliveTemp(T f) {
----------------
damyanp wrote:

What's the plan for when different template instantiations have different availability? Is that intended to be checked here?

```c++
__attribute__((availability(shadermodel, introduced = 6.5)))
float fx(float);  // #fx

__attribute__((availability(shadermodel, introduced = 6.6)))
half fx(half);  // #fx

template<typename T> T t(T f) { return fx(f); }

half test(half x) { return t(x); }
float test(float x) { return t(x); }
```


https://github.com/llvm/llvm-project/pull/92704