1 files changed, 149 insertions, 0 deletions
diff --git a/backend/include/rcc/CodeGen/GlobalISel/GIMatchTableExecutor.h b/backend/include/rcc/CodeGen/GlobalISel/GIMatchTableExecutor.h
new file mode 100644
index 0000000..f191db2
--- /dev/null
+++ b/backend/include/rcc/CodeGen/GlobalISel/GIMatchTableExecutor.h
@@ -0,0 +1,149 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#ifndef RCC_CODEGEN_GLOBALISEL_GIMATCHTABLEEXECUTOR_H
+#define RCC_CODEGEN_GLOBALISEL_GIMATCHTABLEEXECUTOR_H
+
+#include "rcc/CodeGen/MachineIRTypes.h"
+#include "rcc/CodeGen/MachineOperand.h"
+#include "rcc/Support/Error.h"
+
+#include <cstdint>
+#include <optional>
+#include <span>
+#include <string_view>
+#include <vector>
+
+namespace rcc {
+
+class MachineFunction;
+class MachineInstr;
+class TargetDescription;
+
+enum class GIMatchTypeKind : std::uint8_t {
+  Any,
+  Scalar,
+  Pointer,
+};
+
+enum class GIMatchImmediateTransform : std::uint8_t {
+  Identity,
+  Negate,
+  PlusOne,
+};
+
+enum class GIMatchTableOpcode : std::uint8_t {
+  CheckOpcode,
+  CheckOperandType,
+  CheckInstructionFlag,
+  ClearInstructionFlags,
+  CheckOperandBank,
+  CheckOperandClass,
+  CheckIntegerPredicate,
+  CheckFloatingPredicate,
+  CheckMemorySize,
+  CheckTargetPredicate,
+  CheckOperandImmediateRanges,
+  CheckOperandDefConstantRanges,
+  CheckOperandDefOpcode,
+  CheckOperandDefIntegerPredicate,
+  CheckOperandDefOperandConstantRanges,
+  CaptureDefOperand,
+  CreateTemporary,
+  CreateTemporaryType,
+  MutateOpcode,
+  BuildInstruction,
+  RenderOperand,
+  RenderComplexOperand,
+  RenderCapturedOperand,
+  RenderCapturedTypeBits,
+  RenderPhysicalRegister,
+  RenderTemporary,
+  RenderCapturedImmediate,
+  RenderImmediate,
+  ReplaceRootWithCapturedOperand,
+  EraseOperandDefinition,
+  Complete,
+};
+
+struct GIMatchTableInstruction final {
+  GIMatchTableOpcode Opcode = GIMatchTableOpcode::Complete;
+  std::uint16_t OperandIndex = 0;
+  std::uint32_t Value = 0;
+  std::uint32_t Auxiliary = 0;
+  std::int64_t Immediate = 0;
+  std::string_view Symbol;
+};
+
+struct GIMatchComplexInstruction final {
+  Opcode ResultOpcode;
+  LowLevelType ResultType;
+  std::vector<MachineOperand> Operands;
+};
+
+struct GIMatchComplexOperand final {
+  std::optional<MachineOperand> Operand;
+  std::optional<GIMatchComplexInstruction> Instruction;
+};
+
+struct GIMatchTableConstantRange final {
+  std::int64_t Minimum = 0;
+  std::int64_t Maximum = 0;
+};
+
+struct GIMatchTableRule final {
+  std::string_view Name;
+  std::uint32_t Priority = 0;
+  std::uint32_t FirstInstruction = 0;
+  std::uint32_t InstructionCount = 0;
+};
+
+enum class GIMatchTableKind : std::uint8_t {
+  Selection,
+  Combiner,
+};
+
+struct GIMatchTable final {
+  std::span<const GIMatchTableInstruction> Instructions;
+  std::span<const GIMatchTableRule> Rules;
+  std::span<const GIMatchTableConstantRange> ConstantRanges;
+  GIMatchTableKind Kind = GIMatchTableKind::Selection;
+};
+
+class GIMatchTableExecutor {
+public:
+  virtual ~GIMatchTableExecutor() = default;
+
+  [[nodiscard]] Expected<bool> match(const GIMatchTable &Table, const MachineInstr &Instruction,
+                                     const MachineFunction &Function,
+                                     const TargetDescription &Target) const;
+
+  // A false result means that no table rule matched. The executor completes all
+  // predicates before applying the selected rule to MachineIR.
+  [[nodiscard]] Expected<bool> select(const GIMatchTable &Table, MachineInstr &Instruction,
+                                      MachineFunction &Function,
+                                      const TargetDescription &Target) const;
+
+  // Match and apply one generated GlobalISel combiner rule.
+  [[nodiscard]] Expected<bool> combine(const GIMatchTable &Table, MachineInstr &Instruction,
+                                       MachineFunction &Function,
+                                       const TargetDescription &Target) const;
+
+protected:
+  [[nodiscard]] virtual Expected<bool>
+  matchesTargetPredicate(std::string_view Name, const MachineInstr &Instruction,
+                         const MachineFunction &Function, const TargetDescription &Target) const;
+
+  [[nodiscard]] virtual Expected<std::optional<GIMatchComplexOperand>>
+  renderComplexOperand(std::string_view Name, const MachineInstr &Instruction,
+                       const MachineFunction &Function, const TargetDescription &Target,
+                       std::uint32_t OperandIndex) const;
+
+  [[nodiscard]] virtual Expected<void>
+  finalizeGeneratedInstruction(MachineInstr &Output, MachineFunction &Function,
+                               const TargetDescription &Target, MachineInstrFlags InputFlags,
+                               bool InputMayRaiseFPException) const;
+};
+
+} // namespace rcc
+
+#endif // RCC_CODEGEN_GLOBALISEL_GIMATCHTABLEEXECUTOR_H