package midend.optimize;

import midend.llvm.value.IrBasicBlock;
import midend.llvm.value.IrFuncValue;

import java.util.ArrayList;

import midend.llvm.instr.AllocateInstr;
import midend.llvm.instr.IrInstr;
import midend.llvm.type.IrArrayType;

public class MemToReg extends Optimizer {
    public void optimize() {
        for (IrFuncValue func : getIrModule().getFuncs()) {
            IrBasicBlock entryBlock = func.getBBlock(0);
            for (IrBasicBlock block : func.getBBlocks()) {
                ArrayList<IrInstr> instrs = new ArrayList<>(block.getInstrs());
                for (IrInstr instr : instrs) {
                    if (normalAlloca(instr)) {
                        AllocateInstr allocInstr = (AllocateInstr) instr;
                        PhiInsert phiInsert = new PhiInsert(allocInstr, entryBlock);
                        phiInsert.run();
                    }
                }
            }
        }
    }

    public boolean normalAlloca(IrInstr instr) {
        if (!(instr instanceof AllocateInstr)) {
            return false;
        }
        AllocateInstr allocInstr = (AllocateInstr) instr;
        return !(allocInstr.getPointeeType() instanceof IrArrayType);
    }
}