ir_macro_engine.py

class IRMacroEngine:
    """
    Safe macro substitution layer for IR programs.

    Responsibilities:
    - apply learned macros safely
    - prevent structural corruption
    - validate opcode consistency
    - ensure fallback integrity
    """

    def __init__(self, macro_compiler):
        self.macro_compiler = macro_compiler

    # =====================================================
    # MAIN APPLY FUNCTION
    # =====================================================
    def apply(self, program):

        if not program:
            return program

        macros = getattr(self.macro_compiler, "macros", {})

        if not macros:
            return program

        transformed = []

        for instr in program:

            # safety check
            if not isinstance(instr, dict):
                transformed.append(instr)
                continue

            replaced = False

            for name, macro in macros.items():

                if self._matches(instr, macro.get("pattern")):
                    transformed.append({
                        "opcode": name
                    })
                    replaced = True
                    break

            if not replaced:
                transformed.append(instr)

        # final validation pass
        return self._validate(transformed)

    # =====================================================
    # MATCHING LOGIC
    # =====================================================
    def _matches(self, instr, pattern):

        if not pattern:
            return False

        # strict opcode match (prevents false compression)
        if instr.get("opcode") != pattern.get("opcode"):
            return False

        return True

    # =====================================================
    # VALIDATION LAYER (CRITICAL SAFETY GUARD)
    # =====================================================
    def _validate(self, program):

        safe_program = []

        for instr in program:

            if not isinstance(instr, dict):
                continue

            opcode = instr.get("opcode")

            # reject malformed instructions
            if not opcode or not isinstance(opcode, str):
                continue

            safe_program.append(instr)

        # fallback safety: never return empty program
        return safe_program if safe_program else program