ref: 6e944f5fe207cd0294eaa4cd023533771fd403d8
dir: /lib/thread/exit+openbsd-x64.s/
/* const thread.exit : (stacksz : std.size -> void) */ .globl thread$exit thread$exit: /* Because OpenBSD wants a valid stack whenever we enter the kernel, we need to toss a preallocated stack pointer into %rsp. */ movq thread$exitstk,%rsp /* munmap(base, size) */ movq $73,%rax /* munmap */ movq %fs:0x08,%rdi /* base */ movq %fs:0x10,%rsi /* stksz */ syscall /* __threxit(0) */ movq $302,%rax /* exit */ xorq %rdi,%rdi /* 0 */ syscall