Re: Intel P6 vs P7 system call performance

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On 19 Dec, Richard B. Johnson wrote:
> On Thu, 19 Dec 2002 billyrose@billyrose.net wrote:

>> long_call:
>> pushl $0xfffff000
>> ret
>>
>
> Because the number pushed onto the stack is a displacement, not
> an address, i.e., -4095. To have the address act as an address,

Not true. A ret(urn) is (sort of) equivalent to 'pop %eip'. The above
code would actually jump to address 0xfffff000, but probably be slow
since it confuses the branch prediction.

Bart

-- 
Bart Hartgers - TUE Eindhoven 
http://plasimo.phys.tue.nl/bart/contact.html
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