Linux 未在此范围内声明
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Not declared in this scope
提问by Lady_ari
I'm in the process of implementing a MIPS instruction set simulator. But when I try compiling my code, I keep getting "out of scope" errors and it's getting to be very frustrating. I've tried all kinds of variations, but nothing seems to be helping.
Here's my MIPSsim.cpp file
我正在实施 MIPS 指令集模拟器。但是当我尝试编译我的代码时，我不断收到“超出范围”的错误，这让我非常沮丧。我尝试了各种变化，但似乎没有任何帮助。
这是我的 MIPSsim.cpp 文件
#include <iostream>
#include <fstream>
#include <string>
#include <cassert>
using namespace std;
const int BITS = 32;
string inst_decode(string line);
void execute(string line, string instruction, int ®isters[]);
void print(int cycle, int inst_address, int regs[]/*, int data[]*/);
int convert_5(string binary);
int convert_32(string binary);
void add(string line, int ®isters[]);
void sub(string line, int ®isters[]);
void mult(string line, int ®isters[]);
string inst_decode(string line){
string instruction;
if(line.compare(0,1,"0") == 0){
if (line.compare(1,5,"00010") == 0){
cout << "JUMP" << endl;
instruction = "JUMP";
}else if (line.compare(1,5,"00100") == 0){
cout << "BEQ" << endl;
instruction = "BEQ";
}else if (line.compare(1,5,"00001") == 0){
cout << "BLTZ" << endl;
instruction = "BLTZ";
}else if (line.compare(1,5,"00111") == 0){
cout << "BGTZ" << endl;
instruction = "BGTZ";
}else if (line.compare(1,5,"01011") == 0){
cout << "SW" << endl;
instruction = "SW";
}else if (line.compare(1,5,"00011") == 0){
cout << "LW" << endl;
instruction = "LW";
}else if (line.compare(1,5,"00010") == 0){
cout << "SRL" << endl;
instruction = "SRL";
}else if ((line.compare(1,5,"11100") == 0)&&(line.compare(26,6,"000010") == 0)){
cout << "MUL" << endl;
instruction = "MUL";
}else if (line.compare(1,5,"00000") == 0){
if (line.compare(26,6,"100000") == 0){
cout << "ADD" << endl;
instruction = "ADD";
}else if (line.compare(26,6,"100010") == 0){
cout << "SUB" << endl;
instruction = "SUB";
}else if (line.compare(26,6,"100100") == 0){
cout << "AND" << endl;
instruction = "AND";
}else if (line.compare(26,6,"100101") == 0){
cout << "OR" << endl;
instruction = "OR";
}else if (line.compare(26,6,"101010") == 0){
cout << "SLT" << endl;
instruction = "SLT";
}else if (line.compare(26,6,"000000") == 0){
cout << "SLL" << endl;
instruction = "SLL";
}else if (line.compare(6,26,"00000000000000000000000000") == 0){
cout << "NOP" << endl;
instruction = "NOP";
}
}
}else{
if (line.compare(26,6,"100100") == 0){
cout << "ADDI" << endl;
instruction = "ADDI";
}else if (line.compare(26,6,"100010") == 0){
cout << "ANDI" << endl;
instruction = "ANDI";
}
}
return instruction;
}
void execute(string line, string instruction, int& registers[]){
if(instruction == "ADD"){
add(line, registers);
}else if(instruction == "ADDI"){
addi(line, registers);
}else if(instruction == "SUB"){
sub(line, registers);
}else if(instruction == "MUL"){
mult(line, registers);
}
}
void print(int cycle, int inst_address, int regs[]/*, int data[][]*/){
cout << "---------------------------\n";
cout << "Cycle: " << cycle << "\t" << inst_address << "\t" << "\n";
cout << "\nRegisters\n";
cout << "R00:\t";
for(int i=0; i<=15; i++){
cout << regs[i] << "\t";
}
cout << "\nR16:\t";
for(int i=16; i<32; i++){
cout << regs[i] << "\t";
}
cout << "\n\nData\n";
//cout << "\n148:\t";
//for(int i=0; i<8; i++){
// cout << data[i] << "\t";
//}
//cout << "\n180:\t";
//for(int i=9; i<17; i++){
// cout << data[i] << "\t";
//}
//cout << "\n212:\t";
//for(int i=18; i<26; i++){
// cout << data[i] << "\t";
//}
cout << "\n";
}
int main(){
int registers[32] = {0};
// int data[2][32];
string inst;
//int cycle = 1;
//int PC = 64;
string binary_inst[64];
ifstream inFile;
inFile.open("sample.txt");
if (!inFile) {
cout << "Unable to open file sample.txt" << endl;
return 0;
}
string x;
while(!inFile.eof()){
for(int i=0; i<64; i++){
inFile >> x;
binary_inst[i] = x;
inst = inst_decode(binary_inst[i]);
execute(binary_inst[i], inst, registers);
//print(cycle, PC, registers);
}
}
// print(cycle, PC, registers);
return 0;
}
int convert_5(string binary) {
long power = 32;
long sum = 0;
assert(binary.size() == 5);
for ( int i=0; i<BITS; ++i) {
if ( i==0 && binary[i]!='0') {
sum = -32;
}
else {
sum += (binary[i]-'0')*power;
}
power /= 2;
}
return sum;
}
int convert_32(string binary) {
long power = 4294967296;
long sum = 0;
assert(binary.size() == 32);
for ( int i=0; i<BITS; ++i) {
if ( i==0 && binary[i]!='0') {
sum = -4294967296;
}
else {
sum += (binary[i]-'0')*power;
}
power /= 2;
}
return sum;
}
void add(string line, int& registers[]){
int dest = convert_5(line.substr(17,5));
cout << "Dest: " << dest << endl;
int target = convert_5(line.substr(12,5));
cout << "Target: " << target << endl;
int source = convert_5(line.substr(7,5));
cout << "Source: " << source << endl;
registers[dest] = registers[source] + registers[target];
cout << "Addition: " << registers[dest] << endl;
}
void sub(string line, int& registers[]){
int dest = convert_5(line.substr(17,5));
cout << "Dest: " << dest << endl;
int target = convert_5(line.substr(12,5));
cout << "Target: " << target << endl;
int source = convert_5(line.substr(7,5));
cout << "Source: " << source << endl;
registers[dest] = registers[source] - registers[target];
cout << "Subtraction: " << registers[dest] << endl;
}
void mult(string line, int& registers[]){
int dest = convert_5(line.substr(17,5));
cout << "Dest: " << dest << endl;
int target = convert_5(line.substr(12,5));
cout << "Target: " << target << endl;
int source = convert_5(line.substr(7,5));
cout << "Source: " << source << endl;
registers[dest] = registers[source] * registers[target];
cout << "Multiplication: " << registers[dest] << endl;
}
Here are the error messages I keep getting:
以下是我不断收到的错误消息：
lin114-08:10% make all
g++ -Wall -o MIPSsim MIPSsim.cpp
MIPSsim.cpp:10: error: declaration of ‘registers' as array of references
MIPSsim.cpp:14: error: declaration of ‘registers' as array of references
MIPSsim.cpp:15: error: declaration of ‘registers' as array of references
MIPSsim.cpp:16: error: declaration of ‘registers' as array of references
MIPSsim.cpp:85: error: declaration of ‘registers' as array of references
MIPSsim.cpp: In function ‘void execute(...)':
MIPSsim.cpp:86: error: ‘instruction' was not declared in this scope
MIPSsim.cpp:87: error: ‘line' was not declared in this scope
MIPSsim.cpp:87: error: ‘registers' was not declared in this scope
MIPSsim.cpp:89: error: ‘line' was not declared in this scope
MIPSsim.cpp:89: error: ‘registers' was not declared in this scope
MIPSsim.cpp:89: error: ‘addi' was not declared in this scope
MIPSsim.cpp:91: error: ‘line' was not declared in this scope
MIPSsim.cpp:91: error: ‘registers' was not declared in this scope
MIPSsim.cpp:93: error: ‘line' was not declared in this scope
MIPSsim.cpp:93: error: ‘registers' was not declared in this scope
MIPSsim.cpp: In function ‘int main()':
MIPSsim.cpp:146: warning: cannot pass objects of non-POD type ‘struct std::string' through ‘...'; call will abort at runtime
MIPSsim.cpp:146: warning: cannot pass objects of non-POD type ‘struct std::string' through ‘...'; call will abort at runtime
MIPSsim.cpp: At global scope:
MIPSsim.cpp:193: error: declaration of ‘registers' as array of references
MIPSsim.cpp: In function ‘void add(...)':
MIPSsim.cpp:194: error: ‘line' was not declared in this scope
MIPSsim.cpp:203: error: ‘registers' was not declared in this scope
MIPSsim.cpp: At global scope:
MIPSsim.cpp:207: error: declaration of ‘registers' as array of references
MIPSsim.cpp: In function ‘void sub(...)':
MIPSsim.cpp:208: error: ‘line' was not declared in this scope
MIPSsim.cpp:217: error: ‘registers' was not declared in this scope
MIPSsim.cpp: At global scope:
MIPSsim.cpp:221: error: declaration of ‘registers' as array of references
MIPSsim.cpp: In function ‘void mult(...)':
MIPSsim.cpp:222: error: ‘line' was not declared in this scope
MIPSsim.cpp:231: error: ‘registers' was not declared in this scope
make: *** [MIPSsim] Error 1
Any help would be greatly appreciated
任何帮助将不胜感激
采纳答案by Erik
Always fix the firsterror the compiler gives you: int ®isters[]won't work - use int * registersor int registers[].
总是修复编译器给你的第一个错误：int ®isters[]不会工作 - 使用int * registers或int registers[].
If you really want a reference to an array, you need to specify the size:
如果你真的想要一个数组的引用，你需要指定大小：
void execute(string line, string instruction, int (®isters) [10]);
All of these approaches will let you modify the actual array you pass to the function - there's no copying.
所有这些方法都可以让您修改传递给函数的实际数组 - 没有复制。
Side note:
边注：
In MIPSsim.cppline 146 you're trying to pass a std::stringto a vararg function (e.g. sprintfor printf) - That won't work. Pass string.c_str()instead.
在MIPSsim.cpp第 146 行中，您试图将 a 传递std::string给可变参数函数（例如sprintf或printf）-这不起作用。string.c_str()而是通过。
回答by Mark B
I can't say if there are other problems but I think your execute, add, sub, multfunctions can just take registersas an array, not an array of references.
我不能说是否还有其他问题，但我认为您的execute, add, sub,mult函数可以registers作为一个数组，而不是一个引用数组。
void add(string line, int registers[]);
void add(string line, int registers[]);
回答by James Kanze
You can't pass an array as an argument in C++. What you'd have to do is declare the parameters:
您不能在 C++ 中将数组作为参数传递。你必须做的是声明参数：
int (®isters)[32];
But registers aren't the only machine state which is likely to be changed by executing some code. A much better solution would be to define a struct with all of the machine state (except maybe the memory):
但是寄存器并不是唯一可能通过执行某些代码而改变的机器状态。一个更好的解决方案是定义一个包含所有机器状态（可能除了内存）的结构：
struct HWState
{
int registers[32];
unsigned cc;
??? pc;
// ...
};
Then pass that by reference, and you shouldn't have any problem. (In practice, C style arrays should only be used for static variables, with static initialization, and as members, when the count is constant and not too big.)
然后通过引用传递它，你应该没有任何问题。（在实践中，C 风格的数组应该只用于静态变量，静态初始化，并作为成员，当计数恒定且不太大时。）
回答by MSalters
When you have a lot of functions that all take the same argument, that's usually a sign that they should be member functions. Here, you have add, suband multwhich all operate on your set of registers. And of course, most future instructions will too.
当你有很多函数都采用相同的参数时，这通常表明它们应该是成员函数。在这里，您有add,sub并且mult它们都在您的寄存器组上运行。当然，大多数未来的指令也会如此。
Therefore, define a class CPUwith data members for each register (i.e. int r[32];float f[32];, and a method CPU::add(std::string line). Within add, you can just refer to r[4]if you need the first function argument register etc.
因此，class CPU为每个寄存器定义一个with 数据成员（即int r[32];float f[32];，和一个方法CPU::add(std::string line)。在 add 中，您可以参考r[4]是否需要第一个函数参数寄存器等。
