RiscBasicBlock.java

package cn.edu.nju.software.backend;

import cn.edu.nju.software.backend.regalloc.LValLiveTable;
import cn.edu.nju.software.backend.regalloc.TempVarLiveTable;
import cn.edu.nju.software.backend.riscinstruction.*;
import cn.edu.nju.software.backend.riscinstruction.floatextension.RiscFlw;
import cn.edu.nju.software.backend.riscinstruction.operand.ImmediateValue;
import cn.edu.nju.software.backend.riscinstruction.operand.IndirectRegister;
import cn.edu.nju.software.backend.riscinstruction.operand.Register;
import cn.edu.nju.software.backend.riscinstruction.pseudo.RiscLi;
import cn.edu.nju.software.backend.riscinstruction.util.RiscComment;
import cn.edu.nju.software.backend.regalloc.Allocator;
import cn.edu.nju.software.ir.basicblock.BasicBlockRef;
import cn.edu.nju.software.ir.type.*;
import cn.edu.nju.software.ir.value.FunctionValue;
import cn.edu.nju.software.ir.value.LocalVar;
import java.util.ArrayList;
import java.util.List;

public class RiscBasicBlock {

    private final BasicBlockRef basicBlockRef;
    private final Allocator allocator = Allocator.get();
    private final FunctionValue llvmFunctionValue;
    private final List<RiscInstruction> riscInstructions = new ArrayList<>() ;
    private final RiscInstrGenerator generator;
    private final TempVarLiveTable tempVarLiveTable;
    private final LValLiveTable lValLiveTable;

    public RiscBasicBlock(BasicBlockRef basicBlockRef, FunctionValue functionValue) {
        this.basicBlockRef = basicBlockRef;
        this.llvmFunctionValue = functionValue;
        this.generator = new RiscInstrGenerator(basicBlockRef.getIrs(), llvmFunctionValue);
        this.tempVarLiveTable = new TempVarLiveTable(generator, allocator);
        this.lValLiveTable = new LValLiveTable();
    }

    public void codeGen() {
        allocator.setLValLiveTable(lValLiveTable);
        allocator.setTempVarLiveTable(tempVarLiveTable);
        allocator.setInstrGenerator(generator);
        if (basicBlockRef.isEntryBlock()) {
            functionInit();
        }
        riscInstructions.addAll(generator.genRiscInstructions());
    }

    private void functionInit() {
        generator.insertComment("reserve space for all local variables in function");
        int stackSize = allocator.getStackSize();
        if (stackSize > 0) {
            if(stackSize <= 2048){
                generator.addInstruction(new RiscAddi(new Register("sp"), new Register("sp"), new ImmediateValue(-stackSize)));
            } else {
                generator.addInstruction(new RiscLi(new Register("t0"), new ImmediateValue(stackSize)));
                generator.addInstruction(new RiscSub(new Register("sp"), new Register("sp"), new Register("t0")));
            }
        }
        if(!llvmFunctionValue.getName().equals("main")){ //main没有调用函数，也没有参数
            saveCalleeSavedRegs();
            saveParams();
        }
    }

    public RiscInstrGenerator getGenerator() {
        return generator;
    }

    /**
     * 保存参数