[clang] [CIR] cir.call with scalar return type (PR #135552)

[Bruno Cardoso Lopes via cfe-commits]

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@@ -0,0 +1,50 @@
+#include "TargetInfo.h"
+#include "ABIInfo.h"
+#include "CIRGenFunctionInfo.h"
+#include "clang/CIR/MissingFeatures.h"
+
+using namespace clang;
+using namespace clang::CIRGen;
+
+static bool testIfIsVoidTy(QualType ty) {
+  const auto *builtinTy = ty->getAs<BuiltinType>();
+  return builtinTy && builtinTy->getKind() == BuiltinType::Void;
+}
+
+namespace {
+
+class X8664ABIInfo : public ABIInfo {
+public:
+  X8664ABIInfo(CIRGenTypes &cgt) : ABIInfo(cgt) {}
+
+  void computeInfo(CIRGenFunctionInfo &funcInfo) const override;
+};
+
+class X8664TargetCIRGenInfo : public TargetCIRGenInfo {
+public:
+  X8664TargetCIRGenInfo(CIRGenTypes &cgt)
+      : TargetCIRGenInfo(std::make_unique<X8664ABIInfo>(cgt)) {}
+};
+
+} // namespace
+
+void X8664ABIInfo::computeInfo(CIRGenFunctionInfo &funcInfo) const {
+  // Top level CIR has unlimited arguments and return types. Lowering for ABI
+  // specific concerns should happen during a lowering phase. Assume everything
+  // is direct for now.
+  assert(!cir::MissingFeatures::opCallArgs());
+
+  CanQualType retTy = funcInfo.getReturnType();
+  if (testIfIsVoidTy(retTy))
+    funcInfo.getReturnInfo() = cir::ABIArgInfo::getIgnore();
+  else
+    funcInfo.getReturnInfo() =
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bcardosolopes wrote:

are these both paths tested?

https://github.com/llvm/llvm-project/pull/135552