# 1.33.0[−][src]Function core::arch::x86_64::_subborrow_u64

    pub unsafe fn _subborrow_u64(c_in: u8, a: u64, b: u64, out: &mut u64) -> u8

This is supported on x86-64 only.

Add unsigned 64-bit integers a and b with unsigned 8-bit carry-in c_in (carry or overflow flag), and store the unsigned 64-bit result in out, and the carry-out is returned (carry or overflow flag).

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