Messages in this thread | | | Date | Mon, 10 Mar 2008 22:51:45 +0100 | From | Andi Kleen <> | Subject | Re: [PATCH 1/1] Speedfreq-SMI call clobbers ECX |
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> Please also note that these are not clobbers in the strict inline asm > syntax, but rather dummy output values that correspond to actual
Outputs/Inputs are as bad as clobbers in triggering gcc reload ICEs.
> input parameters. I'd consider this a serious compiler flaw, if not > bug, if these would not work. But let's not get into GCC vs.
It is, and it's (mostly) fixed in newer versions, but we're stuck with supporting the older compiler versions unfortunately.
> > For asms with so many clobbers explicit push/pop is usually safer. > > Yes, but it is unneccessary overhead as the compiler can (should!) > find more elegant ways to get those registers back if needed.
This code is not performance critical at all. Safer beats faster any time in such cases.
-Andi
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