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在书中Low-Level Programming: C, Assembly, and Program Execution on Intel® 64 Architecture它说，
On system call arguments The arguments for system calls are stored in a different set of registers than those for functions. The fourth argument is stored in
r10, while a function accepts the fourth argument inrcx!The reason is that
syscallinstruction implicitly usesrcx. System calls cannot accept more than six arguments.
你可以看到这个Stack Overflow post里面也提到了这个,
A system-call is done via the syscall instruction. This clobbers %rcx and %r11, as well as %rax, but other registers are preserved.
我理解破坏 rax 来存储返回码，但为什么 rcx 和 r11 在 syscall 中被破坏>?是否有破坏 rcx/r11 的特定系统调用的列表？有破坏的约定吗？它们在任何系统调用中都被认为是安全的吗？