On 28 April 2010 10:24, Adrian Lienhard <[email protected]> wrote:
> Igor, I was wondering whether you or somebody else have a real example where
> NativeBoost boosts performance. For instance in an often used library class...
>
It depends. I provided comparisons before.
But if you have any real-world example in mind, i will happily
implement it and give you the numbers.
Apparently there is nothing else, which can run faster than native code.
I'm giving you control to implement own primitives using native code.
As for FFI interface you will have a full control on how to coerce
types between C and Smalltalk worlds and so, it will run as fast as
you made it. :)
For example, here the FFI plugin code which coercing a smalltalk
object to integer value for pushing it on stack:
ffiIntegerValueOf: oop
"Support for generic callout. Return an integer value that is coerced
as C would do."
| oopClass |
self inline: true.
(interpreterProxy isIntegerObject: oop) ifTrue:[^interpreterProxy
integerValueOf: oop].
oop == interpreterProxy nilObject ifTrue:[^0]. "@@: should we really
allow this????"
oop == interpreterProxy falseObject ifTrue:[^0].
oop == interpreterProxy trueObject ifTrue:[^1].
oopClass := interpreterProxy fetchClassOf: oop.
oopClass == interpreterProxy classFloat
ifTrue:[^(interpreterProxy floatValueOf: oop) asInteger].
oopClass == interpreterProxy classCharacter
ifTrue:[^interpreterProxy fetchInteger: 0 ofObject: oop].
oopClass == interpreterProxy classLargePositiveInteger
ifTrue:[^interpreterProxy positive32BitValueOf: oop].
^interpreterProxy signed32BitValueOf: oop "<- will fail if not integer".
See , how generic it is? It tries to accept every possible combination
which could be translated to native integer value.
Now, suppose, that you know _exactly_ that your function will be
called only with smallintegers as arguments,
and want to fail primitive if it get called with wrong argument.
This is what you can do with NativeBoost, but you can't with FFI,
because it is C code, compiled and made in stone.
> Cheers,
> Adrian
>
--
Best regards,
Igor Stasenko AKA sig.
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