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Implicit Character -> Integer conversion with basicAt:

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Eliot Miranda-2

Implicit Character -> Integer conversion with basicAt:

Hi Clément,

I provoked some protest last week by rewriting

String>>isAsciiString
^self allSatisfy: [ :each | each asciiValue <= 127 ]

as

String>>isAsciiString
1 to: self basicSize do: [:i| (self basicAt: i) > 127 ifTrue: [^false]].
^true

The speed up is around 5x to 6x.

The question comes does Scorch know that it can implicitly obtain Character asciiValue by substituting a suitable basicAt: for the at:, or is the chain of inference too complex (as yet)?

_,,,^..^,,,_ (phone)

Clément Béra

Re: Implicit Character -> Integer conversion with basicAt:

For this case, it can infer everything. It does not yet optimize successfully the loop without crashes.

But it's been almost 5 years that the Sista project has been going on. When I started, there was already a prototype. It took 3 years to get benchmarks running with little speed-ups. It took a 4th year to get benchmarks showing 2x performance boost and have a benchmark at 10x to show the potential of Scorch. There is still so much to do to get it to production...

Specifically, there are specificities to our closures: we don't have LIFO closure like Lars' Smalltalks, we have a reference to outerContext unlike Javascript, etc. That's a problem mostly solved with FullBlocks but there's still so much work to do there.

I don't know if on the short term we should take decisions on how to write code in our code bases based on Scorch.

On Mon, May 7, 2018 at 5:12 PM, Eliot Miranda <[hidden email]> wrote:

Hi Clément,

I provoked some protest last week by rewriting

String>>isAsciiString
^self allSatisfy: [ :each | each asciiValue <= 127 ]

as

String>>isAsciiString
1 to: self basicSize do: [:i| (self basicAt: i) > 127 ifTrue: [^false]].
^true

The speed up is around 5x to 6x.

The question comes does Scorch know that it can implicitly obtain Character asciiValue by substituting a suitable basicAt: for the at:, or is the chain of inference too complex (as yet)?

_,,,^..^,,,_ (phone)

Clément Béra
https://clementbera.github.io/

https://clementbera.wordpress.com/