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Thread-Topic: Reusing main VM stack for generators
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Date: Fri, 22 Jan 2016 14:43:56 +0000
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Subject: Reusing main VM stack for generators
From: dmitry@zend.com (Dmitry Stogov)

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Hi,


Could you please, take a look into the PoC.

It's incomplete, but may be you get ideas how to fix this.


https://gist.github.com/dstogov/285024375d15cacf2a9b


Few tests are failed, because YIELD may be used as expression in nested cal=
ls (between INIT_FCALL/DO_FCALL), and the caller function restores EG(vm_st=
ack_top), loosing and overwriting that active frame.


<?php
function gen() {
    var_dump(yield 1);
}

for ($gen =3D gen(); $gen->valid(); $gen->send(0)) {
    var_dump($gen->current());
}
?>


Thanks. Dmitry.


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