fetch_sub

Atomically subtract operand from *m_data.

T fetch_sub(T operand, cl::sycl::memory_order mem_order) volatile

1. Atomically subtract operand from *m_data.
   Parameters:
   • T operand : the value to subtract from *m_data.
   • cl::sycl::memory_order mem_order : the ordering to use. Can only be memory_order_relaxed.
   Returns: the old value of m_data.