LLVM编译器相关C++技术

来源：互联网发布：阿里云帐号编辑：程序博客网时间：2024/05/20 06:09

RegisterMCAsmLexer<X86AsmLexer> X(TheX86_32Target);

这个函数里面有个Allocator的赋值，相关的C++技术模拟代码如下，用VC2010编译成功并运行：

// CppTest.cpp : 定义控制台应用程序的入口点。//#include "stdafx.h"class Target;class MCRegisterInfo {};class MCAsmLexer {};class MCAsmInfo {};class MCTargetAsmLexer {//MCTargetAsmLexer(const MCTargetAsmLexer &);   // DO NOT IMPLEMENT//void operator=(const MCTargetAsmLexer &);  // DO NOT IMPLEMENTprotected: // Can only create subclasses.MCTargetAsmLexer(const Target &T): TheTarget(T), Lexer(NULL) {}/// TheTarget - The Target that this machine was created for.const Target &TheTarget;MCAsmLexer *Lexer;};class Target{public:char a;typedef MCTargetAsmLexer *(*MCAsmLexerCtorTy)(const Target &T,const MCRegisterInfo &MRI,const MCAsmInfo &MAI);MCAsmLexerCtorTy MCAsmLexerCtorFn;};struct TargetRegistry {static void RegisterMCAsmLexer(Target &T, Target::MCAsmLexerCtorTy Fn) {if (!T.MCAsmLexerCtorFn)T.MCAsmLexerCtorFn = Fn;}};template<class MCAsmLexerImpl>struct RegisterMCAsmLexer {RegisterMCAsmLexer(Target &T) {TargetRegistry::RegisterMCAsmLexer(T, &Allocator);}private:static MCTargetAsmLexer *Allocator(const Target &T,const MCRegisterInfo &MRI,const MCAsmInfo &MAI) {return new MCAsmLexerImpl(T, MRI, MAI);}};class X86AsmLexer : public MCTargetAsmLexer {const MCAsmInfo &AsmInfo;bool tentativeIsValid;public:X86AsmLexer(const Target &T, const MCRegisterInfo &MRI, const MCAsmInfo &MAI): MCTargetAsmLexer(T), AsmInfo(MAI), tentativeIsValid(false) {}};Target TheX86_32Target;int _tmain(int argc, _TCHAR* argv[]){RegisterMCAsmLexer<X86AsmLexer> X(TheX86_32Target);return 0;}

0 0