1 files changed, 126 insertions, 0 deletions
diff --git a/clang/lib/CIR/CodeGen/CIRGenFunction.cpp b/clang/lib/CIR/CodeGen/CIRGenFunction.cpp
index b4b95d6..c65d025 100644
--- a/clang/lib/CIR/CodeGen/CIRGenFunction.cpp
+++ b/clang/lib/CIR/CodeGen/CIRGenFunction.cpp
@@ -923,4 +923,130 @@ CIRGenFunction::emitArrayLength(const clang::ArrayType *origArrayType,
   return builder.getConstInt(*currSrcLoc, SizeTy, countFromCLAs);
 }
 
+// TODO(cir): Most of this function can be shared between CIRGen
+// and traditional LLVM codegen
+void CIRGenFunction::emitVariablyModifiedType(QualType type) {
+  assert(type->isVariablyModifiedType() &&
+         "Must pass variably modified type to EmitVLASizes!");
+
+  // We're going to walk down into the type and look for VLA
+  // expressions.
+  do {
+    assert(type->isVariablyModifiedType());
+
+    const Type *ty = type.getTypePtr();
+    switch (ty->getTypeClass()) {
+    case Type::CountAttributed:
+    case Type::PackIndexing:
+    case Type::ArrayParameter:
+    case Type::HLSLAttributedResource:
+    case Type::HLSLInlineSpirv:
+    case Type::PredefinedSugar:
+      cgm.errorNYI("CIRGenFunction::emitVariablyModifiedType");
+
+#define TYPE(Class, Base)
+#define ABSTRACT_TYPE(Class, Base)
+#define NON_CANONICAL_TYPE(Class, Base)
+#define DEPENDENT_TYPE(Class, Base) case Type::Class:
+#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base)
+#include "clang/AST/TypeNodes.inc"
+      llvm_unreachable(
+          "dependent type must be resolved before the CIR codegen");
+
+    // These types are never variably-modified.
+    case Type::Builtin:
+    case Type::Complex:
+    case Type::Vector:
+    case Type::ExtVector:
+    case Type::ConstantMatrix:
+    case Type::Record:
+    case Type::Enum:
+    case Type::Using:
+    case Type::TemplateSpecialization:
+    case Type::ObjCTypeParam:
+    case Type::ObjCObject:
+    case Type::ObjCInterface:
+    case Type::ObjCObjectPointer:
+    case Type::BitInt:
+      llvm_unreachable("type class is never variably-modified!");
+
+    case Type::Elaborated:
+      type = cast<clang::ElaboratedType>(ty)->getNamedType();
+      break;
+
+    case Type::Adjusted:
+      type = cast<clang::AdjustedType>(ty)->getAdjustedType();
+      break;
+
+    case Type::Decayed:
+      type = cast<clang::DecayedType>(ty)->getPointeeType();
+      break;
+
+    case Type::Pointer:
+      type = cast<clang::PointerType>(ty)->getPointeeType();
+      break;
+
+    case Type::BlockPointer:
+      type = cast<clang::BlockPointerType>(ty)->getPointeeType();
+      break;
+
+    case Type::LValueReference:
+    case Type::RValueReference:
+      type = cast<clang::ReferenceType>(ty)->getPointeeType();
+      break;
+
+    case Type::MemberPointer:
+      type = cast<clang::MemberPointerType>(ty)->getPointeeType();
+      break;
+
+    case Type::ConstantArray:
+    case Type::IncompleteArray:
+      // Losing element qualification here is fine.
+      type = cast<clang::ArrayType>(ty)->getElementType();
+      break;
+
+    case Type::VariableArray: {
+      cgm.errorNYI("CIRGenFunction::emitVariablyModifiedType VLA");
+      break;
+    }
+
+    case Type::FunctionProto:
+    case Type::FunctionNoProto:
+      type = cast<clang::FunctionType>(ty)->getReturnType();
+      break;
+
+    case Type::Paren:
+    case Type::TypeOf:
+    case Type::UnaryTransform:
+    case Type::Attributed:
+    case Type::BTFTagAttributed:
+    case Type::SubstTemplateTypeParm:
+    case Type::MacroQualified:
+      // Keep walking after single level desugaring.
+      type = type.getSingleStepDesugaredType(getContext());
+      break;
+
+    case Type::Typedef:
+    case Type::Decltype:
+    case Type::Auto:
+    case Type::DeducedTemplateSpecialization:
+      // Stop walking: nothing to do.
+      return;
+
+    case Type::TypeOfExpr:
+      // Stop walking: emit typeof expression.
+      emitIgnoredExpr(cast<clang::TypeOfExprType>(ty)->getUnderlyingExpr());
+      return;
+
+    case Type::Atomic:
+      type = cast<clang::AtomicType>(ty)->getValueType();
+      break;
+
+    case Type::Pipe:
+      type = cast<clang::PipeType>(ty)->getElementType();
+      break;
+    }
+  } while (type->isVariablyModifiedType());
+}
+
 } // namespace clang::CIRGen