Is branch history preserved across function calls or does it get re-initialized every time the function is entered.
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A processor doesn't know anything about function calls. It only knows about addresses where jump and call instructions once executed. Nothing is being reset when you make a function call in a C program. – Hans Passant Mar 28 '14 at 22:10
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@HansPassant Thanks for the info. I associate a function call with a jump, unless its inlined. Glad to know history is maintained across jumps. – san Mar 28 '14 at 22:24
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1The processor does see calls, but there's no reason to reset the history everytime you enter - it would make a horrible predictor without this history. Just think of `while (!finished()) { ...` – Leeor Mar 29 '14 at 14:51