[GlobalISel] Split the generic pipeline components

1 files changed, 35 insertions, 0 deletions

diff --git a/backend/include/rcc/CodeGen/GlobalISel/InstructionSelector.h b/backend/include/rcc/CodeGen/GlobalISel/InstructionSelector.h
new file mode 100644
index 0000000..4c69606
--- /dev/null
+++ b/backend/include/rcc/CodeGen/GlobalISel/InstructionSelector.h
@@ -0,0 +1,35 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#ifndef RCC_CODEGEN_GLOBALISEL_INSTRUCTIONSELECTOR_H
+#define RCC_CODEGEN_GLOBALISEL_INSTRUCTIONSELECTOR_H
+
+#include "rcc/Support/Error.h"
+
+namespace rcc {
+
+class MachineFunction;
+class MachineInstr;
+class TargetDescription;
+
+class InstructionSelector {
+public:
+  virtual ~InstructionSelector() = default;
+
+  [[nodiscard]] virtual Expected<void> select(MachineInstr &Instruction, MachineFunction &Function,
+                                              const TargetDescription &Target) const = 0;
+
+  // Selection matching is read-only and completes before select() mutates MachineIR.
+  [[nodiscard]] virtual Expected<void> canSelect(const MachineInstr &, const MachineFunction &,
+                                                 const TargetDescription &) const {
+    return {};
+  }
+
+  [[nodiscard]] virtual Expected<void>
+  constrainSelectedInstruction(MachineInstr &, MachineFunction &, const TargetDescription &) const {
+    return {};
+  }
+};
+
+} // namespace rcc
+
+#endif // RCC_CODEGEN_GLOBALISEL_INSTRUCTIONSELECTOR_H