[clang] [llvm] [HLSL] Implement ddx/ddy_coarse intrinsics (PR #164831)

[Alexander Johnston via llvm-commits]

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@@ -360,6 +373,19 @@ bool SemaSPIRV::CheckSPIRVBuiltinFunctionCall(const TargetInfo &TI,
   case SPIRV::BI__builtin_spirv_generic_cast_to_ptr_explicit: {
     return checkGenericCastToPtr(SemaRef, TheCall);
   }
+  case SPIRV::BI__builtin_spirv_ddx_coarse:
+  case SPIRV::BI__builtin_spirv_ddy_coarse: {
+    if (SemaRef.checkArgCount(TheCall, 1))
+      return true;
+
+    if (CheckAllArgTypesAreCorrect(&SemaRef, TheCall,
+                                   CheckFloatOrHalfRepresentation))
+      return true;
+
+    QualType RetTy = TheCall->getArg(0)->getType();
+    TheCall->setType(RetTy);
+    break;
+  }
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Alexander-Johnston wrote:

Reverted

https://github.com/llvm/llvm-project/pull/164831