Memory Read Barrier.
Source position: systemh.inc line 929
procedure ReadBarrier;  | 
ReadBarrier is a low-level instruction to force a read barrier in the CPU: all memory reads before the instruction will be finished before this instruction, before memory reads after the instruction occur.
  | 
Memory Read Dependency Barrier.  | 
|
  | 
Memory read/write barrier.  | 
|
  | 
Memory write barrier.  |