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#include "BasicBlock.h"
#include "Constant.h"
#include "Function.h"
#include "IRStmtBuilder.h"
#include "Module.h"
#include "Type.h"
#include <iostream>
#include <memory>
#ifdef DEBUG // 用于调试信息,大家可以在编译过程中通过" -DDEBUG"来开启这一选项
#define DEBUG_OUTPUT std::cout << __LINE__ << std::endl; // 输出行号的简单示例
#else
#define DEBUG_OUTPUT
#endif
#define CONST_INT(num) \
ConstantInt::create(num, module)
#define CONST_FP(num) \
ConstantFloat::create(num, module) // 得到常数值的表示,方便后面多次用到
using namespace SysYF::IR;
int main(){
auto module = Module::create("sysYF while");
auto builder = IRStmtBuilder::create(nullptr, module);
SysYF::Ptr<Type> Int32Type = Type::get_int32_type(module);
auto zero_initializer = ConstantZero::create(Int32Type, module);
auto b = GlobalVariable::create("b", module, Int32Type, false, zero_initializer);//int b=0;
auto a = GlobalVariable::create("a", module, Int32Type, false, CONST_INT(3));//int a=3;
//main函数
auto mainFunTy = FunctionType::create(Int32Type, {});//main函数没有参数
auto mainFun = Function::create(mainFunTy, "main", module);//创建main函数
auto bb = BasicBlock::create(module, "entry",mainFun);//创建一个名为entry的基本块
builder->set_insert_point(bb); // 一个BB的开始,将当前插入指令点的位置设在bb
// while(a>0){
// b = b+a;
// a = a-1;
// }
// return b;
builder->create_store(CONST_INT(0), b);//b=0
builder->create_store(CONST_INT(3), a);//a=3
auto condBB = BasicBlock::create(module, "condBB", mainFun);
auto whileBB = BasicBlock::create(module, "trueBB_while", mainFun);
auto falseBB = BasicBlock::create(module, "falseBB_while", mainFun);
//无条件br
builder->create_br(condBB);//goto condBB
//condBB
builder->set_insert_point(condBB);
auto aLoad = builder->create_load(a);//a
auto icmp = builder->create_icmp_gt(aLoad, CONST_INT(0));//a>0
//条件br
builder->create_cond_br(icmp, whileBB, falseBB);//if(a>0) goto whileBB; else goto falseBB;
//whileBB
builder->set_insert_point(whileBB);
auto bLoad = builder->create_load(b);//b
//b = b+a
auto bAdda = builder->create_iadd(bLoad, aLoad);//b+a
builder->create_store(bAdda, b);//b=b+a
//a = a-1
auto aSub1 = builder->create_isub(aLoad, CONST_INT(1));//a-1
builder->create_store(aSub1, a);//a=a-1
//无条件br
builder->create_br(condBB);//goto condBB
//falseBB
builder->set_insert_point(falseBB);
auto bLoadr = builder->create_load(b);//b
builder->create_ret(bLoadr);//return b
std::cout << module->print();
return 0;
}