Re: [Qemu-devel] TCG flow vs dyngen

[Lluís]

Stefano Bonifazi writes:

> On 01/24/2011 03:32 PM, Peter Maydell wrote:
>>
>> Being a JIT doesn't prohibit counting target instructions executed.
>> It just means that counting them generally requires generating
>> code to do the counting at runtime, so it's a more complicated
>> change to make than it would be in a non-JIT emulator.
>>
> What do you mean? Should I change the code of qemu-user for counting the
> instructions, or should I add code into the target binaries?


If I recall this correctly, target-i386 has a generic function (whose
name I don't remember) called whenever the rdtsc instruction is
executed.

This function rebuilds the counter that contains the number of executed
instructions (more or less, this number can be tuned from a variety of
sources).


Lluis

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