【2025-11-16】现有代码上传

AssemblyGenerator.cpp

@@ -0,0 +1,204 @@
+// AssemblyGenerator.cpp
+#include "AssemblyGenerator.h"
+#include <sstream>
+#include <iostream>
+#include <cctype>
+#include <cassert>
+
+AssemblyGenerator::AssemblyGenerator(const std::vector<Quad> &quads)
+        : quads_(quads), stackSize_(0) {
+    allocateStack();
+}
+
+void AssemblyGenerator::allocateStack() {
+    int offset = 0;
+
+    // 1) 给所有源变量（localOffset_）分配空间
+    for (auto &q : quads_) {
+        if (!q.var.empty() && localOffset_.count(q.var) == 0) {
+            offset += 8;
+            localOffset_[q.var] = offset;
+        }
+    }
+
+    // 2) 给所有临时变量（t1, t2, ...）分配空间
+    for (auto &q : quads_) {
+        if (!q.result.empty() && q.result[0] == 't'
+            && tempOffset_.count(q.result) == 0) {
+            offset += 8;
+            tempOffset_[q.result] = offset;
+        }
+    }
+
+    // 16 字节对齐
+    stackSize_ = ((offset + 15) / 16) * 16;
+}
+
+std::string AssemblyGenerator::generate() {
+    std::ostringstream out;
+
+    // 1) 段和全局符号声明
+    out << ".text\n";
+    out << ".globl _main\n";
+
+    // 2) 如果首条 IR 是一条 "label main"，先输出 _main:，然后 prologue
+    size_t idx = 0;
+    if (!quads_.empty() && quads_[0].op == "label" && quads_[0].result == "main") {
+        out << "_main:\n";
+        emitPrologue(out);
+        idx = 1;
+    } else {
+        // 否则也输出 prologue
+        emitPrologue(out);
+    }
+
+    // 3) 其余指令
+    for (size_t i = idx; i < quads_.size(); ++i) {
+        emitInstruction(quads_[i], out);
+    }
+
+    // 4) epilogue
+    emitEpilogue(out);
+    return out.str();
+}
+
+void AssemblyGenerator::emitPrologue(std::ostream &os) const {
+    os << "\tstp x29, x30, [sp, #-16]!   // push FP, LR\n";
+    os << "\tmov x29, sp\n";
+    if (stackSize_ > 0) {
+        os << "\tsub sp, sp, #" << stackSize_ << "\n";
+    }
+}
+
+void AssemblyGenerator::emitEpilogue(std::ostream &os) const {
+    if (stackSize_ > 0) {
+        os << "\tadd sp, sp, #" << stackSize_ << "\n";
+    }
+    os << "\tldp x29, x30, [sp], #16   // pop FP, LR\n";
+    os << "\tret\n";
+}
+
+void AssemblyGenerator::loadOperand(const std::string &name, std::ostream &os) const {
+    if (!name.empty() && std::isdigit(name[0])) {
+        // 立即数
+        os << "\tmov w9, #" << name << "\n";
+    }
+    else if (localOffset_.count(name)) {
+        // 局部变量
+        os << "\tldr w9, [x29, #-" << localOffset_.at(name) << "]\n";
+    }
+    else if (tempOffset_.count(name)) {
+        // 临时变量
+        os << "\tldr w9, [x29, #-" << tempOffset_.at(name) << "]\n";
+    }
+    else {
+        // 全局变量
+        os << "\tadrp x10, " << name << "\n";
+        os << "\tadd  x10, x10, :lo12:" << name << "\n";
+        os << "\tldr w9, [x10]\n";
+    }
+}
+
+void AssemblyGenerator::storeResult(const std::string &name, std::ostream &os) const {
+    if (localOffset_.count(name)) {
+        // 局部变量
+        os << "\tstr w9, [x29, #-" << localOffset_.at(name) << "]\n";
+    }
+    else if (tempOffset_.count(name)) {
+        // 临时变量
+        os << "\tstr w9, [x29, #-" << tempOffset_.at(name) << "]\n";
+    }
+    else {
+        // 全局变量
+        os << "\tadrp x10, " << name << "\n";
+        os << "\tadd  x10, x10, :lo12:" << name << "\n";
+        os << "\tstr w9, [x10]\n";
+    }
+}
+
+void AssemblyGenerator::emitInstruction(const Quad &q, std::ostream &os) const {
+    using std::string;
+
+    // 标签
+    if (q.op == "label") {
+        // 非 main 的其他标签直接原样输出
+        if (q.result != "main") {
+            os << q.result << ":\n";
+        }
+        return;
+    }
+
+    // 无条件跳转
+    if (q.op == "goto") {
+        os << "\tb " << q.result << "\n";
+        return;
+    }
+
+    // ifFalse x -> cmp x, #0; beq L
+    if (q.op == "ifFalse") {
+        loadOperand(q.arg1, os);
+        os << "\tcmp w9, #0\n";
+        os << "\tbeq " << q.result << "\n";
+        return;
+    }
+
+    // 赋值 =
+    if (q.op == "=") {
+        loadOperand(q.arg1, os);
+        storeResult(q.result, os);
+        return;
+    }
+
+    // 二元算术/逻辑运算
+    static const std::unordered_map<string, string> binOpMap = {
+            { "+",  "add"  }, { "-",  "sub"  }, { "*",   "mul"  },
+            { "/",  "sdiv" }, { "<<", "lsl"  }, { ">>",  "lsr"  },
+            { "&",  "and"  }, { "|",  "orr"  }, { "^",   "eor"  }
+    };
+    if (binOpMap.count(q.op)) {
+        loadOperand(q.arg1, os);
+        os << "\tmov w10, w9\n";
+        loadOperand(q.arg2, os);
+        os << "\tmov w11, w9\n";
+        os << "\t" << binOpMap.at(q.op) << " w9, w10, w11\n";
+        storeResult(q.result, os);
+        return;
+    }
+
+    // 比较运算，使用 cset 生成布尔 0/1
+    static const std::unordered_map<string, string> cmpCondMap = {
+            {"==", "eq"}, {"!=", "ne"},
+            {"<",  "lt"}, {">",  "gt"},
+            {"<=", "le"}, {">=", "ge"}
+    };
+    if (cmpCondMap.count(q.op)) {
+        loadOperand(q.arg1, os);
+        os << "\tmov w10, w9\n";
+        loadOperand(q.arg2, os);
+        os << "\tmov w11, w9\n";
+        os << "\tcmp w10, w11\n";
+        os << "\tcset w9, " << cmpCondMap.at(q.op) << "\n";
+        storeResult(q.result, os);
+        return;
+    }
+
+    // call / param / return
+    if (q.op == "param") {
+        return;
+    }
+    if (q.op == "call") {
+        os << "\tbl " << q.arg1 << "\n";
+        os << "\tmov w9, w0\n";
+        storeResult(q.result, os);
+        return;
+    }
+    if (q.op == "return") {
+        if (!q.arg1.empty()) {
+            loadOperand(q.arg1, os);
+            os << "\tmov w0, w9\n";
+        }
+        return;
+    }
+
+    std::cerr << "Unhandled IR op: " << q.op << "\n";
+}