[clang] [llvm] [HLSL][DXIL] Implement `refract` intrinsic (PR #136026)

[Sarah Spall via cfe-commits]

================
@@ -16,88 +16,90 @@ namespace clang {
 
 SemaSPIRV::SemaSPIRV(Sema &S) : SemaBase(S) {}
 
+/// Checks if the first `NumArgsToCheck` arguments of a function call are of
+/// vector type. If any of the arguments is not a vector type, it emits a
+/// diagnostic error and returns `true`. Otherwise, it returns `false`.
+///
+/// \param TheCall The function call expression to check.
+/// \param NumArgsToCheck The number of arguments to check for vector type.
+/// \return `true` if any of the arguments is not a vector type, `false`
+/// otherwise.
+
+bool SemaSPIRV::CheckVectorArgs(CallExpr *TheCall, unsigned NumArgsToCheck) {
+  for (unsigned i = 0; i < NumArgsToCheck; ++i) {
+    ExprResult Arg = TheCall->getArg(i);
+    QualType ArgTy = Arg.get()->getType();
+    auto *VTy = ArgTy->getAs<VectorType>();
+    if (VTy == nullptr) {
+      SemaRef.Diag(Arg.get()->getBeginLoc(),
+                   diag::err_typecheck_convert_incompatible)
+          << ArgTy
+          << SemaRef.Context.getVectorType(ArgTy, 2, VectorKind::Generic) << 1
+          << 0 << 0;
+      return true;
+    }
+  }
+  return false;
+}
+
 bool SemaSPIRV::CheckSPIRVBuiltinFunctionCall(unsigned BuiltinID,
                                               CallExpr *TheCall) {
   switch (BuiltinID) {
   case SPIRV::BI__builtin_spirv_distance: {
     if (SemaRef.checkArgCount(TheCall, 2))
       return true;
 
-    ExprResult A = TheCall->getArg(0);
-    QualType ArgTyA = A.get()->getType();
-    auto *VTyA = ArgTyA->getAs<VectorType>();
-    if (VTyA == nullptr) {
-      SemaRef.Diag(A.get()->getBeginLoc(),
-                   diag::err_typecheck_convert_incompatible)
-          << ArgTyA
-          << SemaRef.Context.getVectorType(ArgTyA, 2, VectorKind::Generic) << 1
-          << 0 << 0;
-      return true;
-    }
-
-    ExprResult B = TheCall->getArg(1);
-    QualType ArgTyB = B.get()->getType();
-    auto *VTyB = ArgTyB->getAs<VectorType>();
-    if (VTyB == nullptr) {
-      SemaRef.Diag(A.get()->getBeginLoc(),
-                   diag::err_typecheck_convert_incompatible)
-          << ArgTyB
-          << SemaRef.Context.getVectorType(ArgTyB, 2, VectorKind::Generic) << 1
-          << 0 << 0;
+    // Use the helper function to check both arguments
+    if (CheckVectorArgs(TheCall, 2))
       return true;
-    }
 
-    QualType RetTy = VTyA->getElementType();
+    QualType RetTy =
+        TheCall->getArg(0)->getType()->getAs<VectorType>()->getElementType();
     TheCall->setType(RetTy);
     break;
   }
   case SPIRV::BI__builtin_spirv_length: {
     if (SemaRef.checkArgCount(TheCall, 1))
       return true;
-    ExprResult A = TheCall->getArg(0);
-    QualType ArgTyA = A.get()->getType();
-    auto *VTy = ArgTyA->getAs<VectorType>();
-    if (VTy == nullptr) {
-      SemaRef.Diag(A.get()->getBeginLoc(),
-                   diag::err_typecheck_convert_incompatible)
-          << ArgTyA
-          << SemaRef.Context.getVectorType(ArgTyA, 2, VectorKind::Generic) << 1
-          << 0 << 0;
+
+    // Use the helper function to check the argument
+    if (CheckVectorArgs(TheCall, 1))
       return true;
-    }
-    QualType RetTy = VTy->getElementType();
+
+    QualType RetTy =
+        TheCall->getArg(0)->getType()->getAs<VectorType>()->getElementType();
     TheCall->setType(RetTy);
     break;
   }
-  case SPIRV::BI__builtin_spirv_reflect: {
-    if (SemaRef.checkArgCount(TheCall, 2))
+  case SPIRV::BI__builtin_spirv_refract: {
+    if (SemaRef.checkArgCount(TheCall, 3))
       return true;
 
-    ExprResult A = TheCall->getArg(0);
-    QualType ArgTyA = A.get()->getType();
-    auto *VTyA = ArgTyA->getAs<VectorType>();
-    if (VTyA == nullptr) {
-      SemaRef.Diag(A.get()->getBeginLoc(),
-                   diag::err_typecheck_convert_incompatible)
-          << ArgTyA
-          << SemaRef.Context.getVectorType(ArgTyA, 2, VectorKind::Generic) << 1
-          << 0 << 0;
+    // Use the helper function to check the first two arguments
+    if (CheckVectorArgs(TheCall, 2))
----------------
spall wrote:

Same comment here about following the SemaHLSL style. 

https://github.com/llvm/llvm-project/pull/136026