overhaul pthread cancellation

[musl] / src / thread / x86_64 / syscall_cp.s

.text
.global __syscall_cp_asm
.type   __syscall_cp_asm,%function
__syscall_cp_asm:
        lea 1f(%rip),%rax
        mov %rax,8(%rdi)
        mov %rsp,(%rdi)
        mov 16(%rdi),%eax
        test %eax,%eax
        jnz 2f
        mov %rsi,%rax
        mov %rdx,%rdi
        mov %rcx,%rsi
        mov %r8,%rdx
        mov %r9,%r10
        mov 8(%rsp),%r8
        mov 16(%rsp),%r9
1:      syscall
        ret
2:      xor %edi,%edi
        mov %rdi,8(%r10)
        mov %rdi,(%r10)
        dec %rdi
        jmp pthread_exit