[MC] Implement RV64GC assembly emission

1 files changed, 109 insertions, 0 deletions

diff --git a/backend/include/rcc/MC/MCExpr.h b/backend/include/rcc/MC/MCExpr.h
new file mode 100644
index 0000000..15ff6fd
--- /dev/null
+++ b/backend/include/rcc/MC/MCExpr.h
@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#ifndef RCC_MC_MCEXPR_H
+#define RCC_MC_MCEXPR_H
+
+#include "rcc/MC/MCSymbol.h"
+#include "rcc/Support/Error.h"
+
+#include <cstddef>
+#include <cstdint>
+#include <memory>
+#include <optional>
+#include <variant>
+
+namespace rcc::mc {
+
+class MCExpr;
+using MCExprRef = std::shared_ptr<const MCExpr>;
+
+enum class MCUnaryOperator : std::uint8_t {
+  Plus,
+  Minus,
+  BitwiseNot,
+  LogicalNot,
+};
+
+enum class MCBinaryOperator : std::uint8_t {
+  Add,
+  Subtract,
+  Multiply,
+  Divide,
+  Modulo,
+  ShiftLeft,
+  ShiftRight,
+  BitwiseAnd,
+  BitwiseOr,
+  BitwiseXor,
+  LogicalAnd,
+  LogicalOr,
+  Equal,
+  NotEqual,
+  Less,
+  LessEqual,
+  Greater,
+  GreaterEqual,
+};
+
+struct MCSymbolRefExpr final {
+  MCSymbolRef Symbol;
+};
+
+struct MCUnaryExpr final {
+  MCUnaryOperator Operator = MCUnaryOperator::Plus;
+  MCExprRef Operand;
+};
+
+struct MCBinaryExpr final {
+  MCBinaryOperator Operator = MCBinaryOperator::Add;
+  MCExprRef Left;
+  MCExprRef Right;
+};
+
+struct MCTargetExpr final {
+  std::uint32_t Kind = 0;
+  MCExprRef Operand;
+};
+
+class MCExpr final {
+public:
+  enum class Kind : std::uint8_t {
+    Constant,
+    SymbolRef,
+    Unary,
+    Binary,
+    Target,
+  };
+
+  [[nodiscard]] static MCExprRef constant(std::int64_t Value);
+  [[nodiscard]] static Expected<MCExprRef> symbol(MCSymbolRef Symbol);
+  [[nodiscard]] static Expected<MCExprRef> unary(MCUnaryOperator Operator, MCExprRef Operand);
+  [[nodiscard]] static Expected<MCExprRef> binary(MCBinaryOperator Operator, MCExprRef Left,
+                                                  MCExprRef Right);
+  [[nodiscard]] static Expected<MCExprRef> target(std::uint32_t Kind, MCExprRef Operand);
+
+  [[nodiscard]] Kind kind() const noexcept {
+    return ExpressionKind;
+  }
+
+  template <typename ValueT> [[nodiscard]] const ValueT *getIf() const noexcept {
+    return std::get_if<ValueT>(&Storage);
+  }
+
+  [[nodiscard]] Expected<void> verify(std::size_t MaximumDepth = 256) const;
+  [[nodiscard]] std::optional<std::int64_t> evaluateAbsolute() const noexcept;
+
+private:
+  using StorageT =
+      std::variant<std::int64_t, MCSymbolRefExpr, MCUnaryExpr, MCBinaryExpr, MCTargetExpr>;
+
+  MCExpr(Kind ExpressionKind, StorageT Storage)
+      : ExpressionKind(ExpressionKind), Storage(std::move(Storage)) {}
+
+  Kind ExpressionKind;
+  StorageT Storage;
+};
+
+} // namespace rcc::mc
+
+#endif // RCC_MC_MCEXPR_H