1 files changed, 196 insertions, 0 deletions
diff --git a/backend/include/rcc/CodeGen/GlobalObject.h b/backend/include/rcc/CodeGen/GlobalObject.h
new file mode 100644
index 0000000..49f1f42
--- /dev/null
+++ b/backend/include/rcc/CodeGen/GlobalObject.h
@@ -0,0 +1,196 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#ifndef RCC_CODEGEN_GLOBALOBJECT_H
+#define RCC_CODEGEN_GLOBALOBJECT_H
+
+#include "rcc/CodeGen/GenericConstant.h"
+#include "rcc/CodeGen/MachineIRTypes.h"
+#include "rcc/CodeGen/TargetConstant.h"
+#include "rcc/Support/Error.h"
+
+#include <cstddef>
+#include <cstdint>
+#include <memory>
+#include <optional>
+#include <string>
+#include <utility>
+#include <variant>
+#include <vector>
+
+namespace rcc {
+
+class GlobalInitializer;
+using GlobalInitializerRef = std::shared_ptr<const GlobalInitializer>;
+
+struct GlobalZeroFill final {
+  std::uint64_t Size = 0;
+};
+
+struct GlobalRepeatedInitializer final {
+  std::uint64_t Count = 0;
+  GlobalInitializerRef Value;
+};
+
+struct GlobalAggregateInitializer final {
+  std::vector<GlobalInitializerRef> Elements;
+};
+
+struct GlobalSymbolAddress final {
+  std::string Symbol;
+  std::int64_t Addend = 0;
+  std::uint8_t Size = 8;
+  std::uint32_t TargetFlags = 0;
+};
+
+struct GlobalSymbolDifference final {
+  std::string Minuend;
+  std::string Subtrahend;
+  std::int64_t Addend = 0;
+  std::uint8_t Size = 8;
+};
+
+struct GlobalAlignmentPadding final {
+  std::uint64_t Size = 0;
+  std::uint8_t Fill = 0;
+};
+
+struct GlobalUndefinedStorage final {
+  std::uint64_t Size = 0;
+};
+
+class GlobalInitializer final {
+public:
+  enum class Kind : std::uint8_t {
+    Invalid,
+    Integer,
+    Floating,
+    Bytes,
+    ZeroFill,
+    Repeated,
+    Aggregate,
+    SymbolAddress,
+    SymbolDifference,
+    Target,
+    AlignmentPadding,
+    UndefinedStorage,
+  };
+
+  GlobalInitializer() = default;
+  GlobalInitializer(const GlobalInitializer &) = delete;
+  GlobalInitializer &operator=(const GlobalInitializer &) = delete;
+  GlobalInitializer(GlobalInitializer &&) noexcept = default;
+  GlobalInitializer &operator=(GlobalInitializer &&) noexcept = default;
+  ~GlobalInitializer() = default;
+
+  [[nodiscard]] static GlobalInitializer integer(IntegerImmediate Value);
+  [[nodiscard]] static GlobalInitializer floating(FloatingPointBits Value);
+  [[nodiscard]] static Expected<GlobalInitializer> bytes(std::vector<std::byte> Value);
+  [[nodiscard]] static Expected<GlobalInitializer> zeroFill(std::uint64_t Size);
+  [[nodiscard]] static Expected<GlobalInitializer> repeated(std::uint64_t Count,
+                                                            GlobalInitializer Value);
+  [[nodiscard]] static Expected<GlobalInitializer>
+  aggregate(std::vector<GlobalInitializer> Elements);
+  [[nodiscard]] static Expected<GlobalInitializer> symbolAddress(GlobalSymbolAddress Value);
+  [[nodiscard]] static Expected<GlobalInitializer> symbolDifference(GlobalSymbolDifference Value);
+  [[nodiscard]] static Expected<GlobalInitializer> target(TargetConstant Value);
+  [[nodiscard]] static Expected<GlobalInitializer> alignmentPadding(std::uint64_t Size,
+                                                                    std::uint8_t Fill = 0);
+  [[nodiscard]] static Expected<GlobalInitializer> undefinedStorage(std::uint64_t Size);
+
+  [[nodiscard]] Kind kind() const noexcept;
+
+  template <typename ValueT> [[nodiscard]] const ValueT *getIf() const noexcept {
+    return std::get_if<ValueT>(&Storage);
+  }
+
+  [[nodiscard]] Expected<void> verify(std::size_t MaximumDepth = 1024) const;
+  [[nodiscard]] Expected<std::uint64_t> storageSize(std::size_t MaximumDepth = 1024) const;
+
+private:
+  using StorageT =
+      std::variant<std::monostate, IntegerImmediate, FloatingPointBits, std::vector<std::byte>,
+                   GlobalZeroFill, GlobalRepeatedInitializer, GlobalAggregateInitializer,
+                   GlobalSymbolAddress, GlobalSymbolDifference, TargetConstant,
+                   GlobalAlignmentPadding, GlobalUndefinedStorage>;
+
+  explicit GlobalInitializer(StorageT Storage) : Storage(std::move(Storage)) {}
+
+  StorageT Storage;
+};
+
+enum class GlobalLinkage : std::uint8_t {
+  External,
+  AvailableExternally,
+  LinkOnceAny,
+  LinkOnceODR,
+  WeakAny,
+  WeakODR,
+  Appending,
+  Internal,
+  Private,
+  ExternalWeak,
+  Common,
+  Count,
+};
+
+enum class GlobalVisibility : std::uint8_t {
+  Default,
+  Hidden,
+  Protected,
+  Count,
+};
+
+enum class GlobalTLSModel : std::uint8_t {
+  None,
+  GeneralDynamic,
+  LocalDynamic,
+  InitialExec,
+  LocalExec,
+  Count,
+};
+
+enum class GlobalUnnamedAddress : std::uint8_t {
+  None,
+  Local,
+  Global,
+  Count,
+};
+
+struct GlobalObjectDesc final {
+  std::string Symbol;
+  GenericConstantType ObjectType;
+  GlobalLinkage Linkage = GlobalLinkage::External;
+  GlobalVisibility Visibility = GlobalVisibility::Default;
+  bool DSOLocal = false;
+  std::optional<std::string> Section;
+  Alignment Align;
+  std::uint64_t Size = 0;
+  std::uint32_t AddressSpace = 0;
+  GlobalTLSModel TLSModel = GlobalTLSModel::None;
+  bool ExternallyInitialized = false;
+  std::optional<std::string> COMDAT;
+  bool IsConstant = false;
+  GlobalUnnamedAddress UnnamedAddress = GlobalUnnamedAddress::None;
+  std::optional<GlobalInitializer> Initializer;
+  std::vector<std::string> DebugExpressions;
+  std::optional<OriginID> StableOrigin;
+  std::uint64_t TargetFlags = 0;
+  std::vector<std::pair<std::string, std::string>> TargetAttributes;
+
+  GlobalObjectDesc() = default;
+  GlobalObjectDesc(const GlobalObjectDesc &) = delete;
+  GlobalObjectDesc &operator=(const GlobalObjectDesc &) = delete;
+  GlobalObjectDesc(GlobalObjectDesc &&) noexcept = default;
+  GlobalObjectDesc &operator=(GlobalObjectDesc &&) noexcept = default;
+  ~GlobalObjectDesc() = default;
+
+  [[nodiscard]] bool isDeclaration() const noexcept {
+    return !Initializer.has_value() && Linkage != GlobalLinkage::Common;
+  }
+
+  [[nodiscard]] Expected<void> verify() const;
+};
+
+} // namespace rcc
+
+#endif // RCC_CODEGEN_GLOBALOBJECT_H