nopcoder/ir_optimizer.py at main · dotpipe/nopcoder · GitHub

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class IROptimizer:
    """
    Simple optimization passes:
    - remove NOOP
    - constant folding (basic)
    - redundant LOAD elimination
    """

    def optimize(self, program):
        program = self._remove_noop(program)
        program = self._collapse_adjacent_loads(program)
        return program

    # -----------------------------
    def _remove_noop(self, program):
        return [p for p in program if p["opcode"] != "NOOP"]

    # -----------------------------
    def _collapse_adjacent_loads(self, program):
        optimized = []
        last_loads = {}

        for instr in program:
            op = instr["opcode"]

            if op == "LOAD":
                reg = instr["arg1"]
                val = instr["arg2"]

                # overwrite previous load if same register
                last_loads[reg] = val
                continue

            optimized.append(instr)

        # reinsert final loads
        for reg, val in last_loads.items():
            optimized.insert(0, {
                "opcode": "LOAD",
                "arg1": reg,
                "arg2": val,
                "arg3": None
            })

        return optimized