Справочник Пользователя для AMD 250
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Branch Optimizations
Chapter 6
25112
Rev. 3.06
September 2005
Software Optimization Guide for AMD64 Processors
6.4
Pairing CALL and RETURN
Optimization
Always use care when pairing CALLs and RETURNs.
Application
This optimization applies to:
•
32-bit software
•
64-bit software
Rationale
When the 12-entry return-address stack gets out of synchronization, the latency of returns increases.
The return-address stack becomes unsynchronized when:
The return-address stack becomes unsynchronized when:
•
Calls and returns do not match.
•
The depth of the return-address stack is exceeded because of too many levels of nested function
calls.
calls.