[IR]phi指令重构，将block信息加入并提供新方法，后续需更改phi相关指令构建逻辑

src/IR.cpp

@@ -545,6 +545,83 @@ void User::replaceOperand(unsigned index, Value *value) {
   value->addUse(use);
 }
 
+/**
+ * phi相关函数
+ */
+
+ Value* PhiInst::getvalfromBlk(BasicBlock* blk){
+  refreshB2VMap();
+  if( blk2val.find(blk) != blk2val.end()) {
+    return blk2val.at(blk);
+  }
+  return nullptr;
+}
+
+BasicBlock* PhiInst::getBlkfromVal(Value* val){
+  // 返回第一个值对应的基本块
+  for(unsigned i = 0; i < vsize; i++) {
+    if(getValue(i) == val) {
+      return getBlock(i);
+    }
+  }
+  return nullptr;
+}
+
+void PhiInst::delValue(Value* val){
+  //根据value删除对应的基本块和值
+  unsigned i = 0;
+  BasicBlock* blk = getBlkfromVal(val);
+  for(i = 0; i < vsize; i++) {
+    if(getValue(i) == val) {
+      break;
+    }
+  }
+  removeOperand(2 * i + 1); // 删除blk
+  removeOperand(2 * i); // 删除val
+  vsize--;
+  blk2val.erase(blk); // 删除blk2val映射
+}
+
+void PhiInst::delBlk(BasicBlock* blk){
+  //根据Blk删除对应的基本块和值
+  unsigned i = 0;
+  Value* val = getvalfromBlk(blk);
+  for(i = 0; i < vsize; i++) {
+    if(getBlock(i) == blk) {
+      break;
+    }
+  }
+  removeOperand(2 * i + 1); // 删除blk
+  removeOperand(2 * i); // 删除val
+  vsize--;
+  blk2val.erase(blk); // 删除blk2val映射
+}
+
+void PhiInst::replaceBlk(BasicBlock* newBlk, unsigned k){
+  refreshB2VMap();
+  Value* val = blk2val.at(getBlock(k));
+  // 替换基本块
+  setOperand(2 * k + 1, newBlk);
+  // 替换blk2val映射
+  blk2val.erase(getBlock(k));
+  blk2val.emplace(newBlk, val);
+}
+
+void PhiInst::replaceold2new(BasicBlock* oldBlk, BasicBlock* newBlk){
+  refreshB2VMap();
+  Value* val = blk2val.at(oldBlk);
+  // 替换基本块
+  delBlk(oldBlk);
+  addIncoming(val, newBlk);
+}
+
+void PhiInst::refreshB2VMap(){
+  blk2val.clear();
+  for(unsigned i = 0; i < vsize; i++) {
+    blk2val.emplace(getBlock(i), getValue(i));
+  }
+}
+
 CallInst::CallInst(Function *callee, const std::vector<Value *> &args, BasicBlock *parent, const std::string &name)
     : Instruction(kCall, callee->getReturnType(), parent, name) {
   addOperand(callee);