__isync, __builtin_ppc_isync

Purpose

Instruction Synchronize

Waits for all previous instructions to complete and then discards any prefetched instructions, causing subsequent instructions to be fetched (or refetched) and executed in the context established by previous instructions.

Prototype

void __builtin_ppc_isync (void);

void __isync (void);

Note:
  • The built-in function in the form of __name is a synonym of the built-in function in the form of __builtin_ppc_name.
  • The built-in function in the form of __name is provided for compatibility with IBM® XL C/C++ for AIX® 16.1.0 or earlier releases. This built-in function form might be deprecated in the future.
Note:

This function generates the hardware instruction but does not act as an instruction movement barrier within the compiler. If that is needed, you must also use the __fence function.