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分享register const int a;为什么要加register呢？
见到书上有写到register int a=1;
register const int a 等等，不知道为什么要加register,有什么作用吗？
register const int a 等等，不知道为什么要加register,有什么作用吗？
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bobob 2006-01-13
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直接访问寄存器,不用读内存
加上的话会优化,除非不能优化
加上的话会优化,除非不能优化
pomelowu 2006-01-13
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加register表示尽可能地优化，不加有可能被优化
pomelowu 2006-01-13
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是的
zhanghengbo 2006-01-13
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那也就是说我完全可以不加register，是这样吗？
xhwu3721 2006-01-13
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哪些编译器可以自动优化啊?VC行不行?
菜牛 2006-01-12
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一些编译器可以把register修饰的变量优化为寄存器变量，使程序性能得到优化，不过现在很多编译器即使不加register修饰也可能会自动优化。
vcmute 2006-01-12
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放在寄存器中，访问速度快
register
register declarator
The register keyword specifies that the variable is to be stored in a machine register, if possible.
The 32-bit compiler does not honor user requests for register variables. Instead it makes its own register choices when global optimizations are on. However, all other semantics associated with the register keyword are honored by the 32-bit compiler.
register
register declarator
The register keyword specifies that the variable is to be stored in a machine register, if possible.
The 32-bit compiler does not honor user requests for register variables. Instead it makes its own register choices when global optimizations are on. However, all other semantics associated with the register keyword are honored by the 32-bit compiler.
static inline int register_chrdev(unsigned int major, const char *name, const struct file_operations
