• Guillaume Piolat (8/8) Sep 16 2018 Anyone has any information about the ABI of delegates?
• Guillaume Piolat (4/6) Sep 16 2018 Related thread:
• Vladimir Panteleev (5/13) Sep 16 2018 Have a look at the implementation of toDelegate, which does
• Guillaume Piolat (9/25) Sep 17 2018 Thanks.
• Jacob Carlborg (17/26) Sep 19 2018 You can explicitly set the context pointer of a delegate using the

Guillaume Piolat <spam smam.org> writes:

Anyone has any information about the ABI of delegates?

In particular how to call them with a particular "this"/frame 
pointer?

To solve a hairy problem I need a delegate with a synthesized 
frame pointer.
https://dpaste.dzfl.pl/cf44417c98f9

The problem is that delegate forwarding seems to require GC 
closures. I want manually-managed closures.

Guillaume Piolat <spam smam.org> writes:

On Sunday, 16 September 2018 at 14:12:27 UTC, Guillaume Piolat 
wrote:
 In particular how to call them with a particular "this"/frame 
 pointer?


Related thread: 
https://forum.dlang.org/post/wjbhpztovxratexaobpp forum.dlang.org

Vladimir Panteleev <thecybershadow.lists gmail.com> writes:

On Sunday, 16 September 2018 at 14:12:27 UTC, Guillaume Piolat 
wrote:
 Anyone has any information about the ABI of delegates?

 In particular how to call them with a particular "this"/frame 
 pointer?

 To solve a hairy problem I need a delegate with a synthesized 
 frame pointer.
 https://dpaste.dzfl.pl/cf44417c98f9

 The problem is that delegate forwarding seems to require GC 
 closures. I want manually-managed closures.

Have a look at the implementation of toDelegate, which does 
exactly this:

https://github.com/dlang/phobos/blob/v2.082.0/std/functional.d#L1463

Guillaume Piolat <spam smam.org> writes:

On Sunday, 16 September 2018 at 14:45:08 UTC, Vladimir Panteleev 
wrote:
 On Sunday, 16 September 2018 at 14:12:27 UTC, Guillaume Piolat 
 wrote:
 Anyone has any information about the ABI of delegates?

 In particular how to call them with a particular "this"/frame 
 pointer?

 To solve a hairy problem I need a delegate with a synthesized 
 frame pointer.
 https://dpaste.dzfl.pl/cf44417c98f9

 The problem is that delegate forwarding seems to require GC 
 closures. I want manually-managed closures.

 Have a look at the implementation of toDelegate, which does 
 exactly this:

 https://github.com/dlang/phobos/blob/v2.082.0/std/functional.d#L1463

Thanks.

I ended up using toDelegate internally, and enclosing the 
resulting delegate with code returning a struct with `opCall`.

The conclusion is that "struct with `opCall`" is much easier to 
implement that faking delegate ABI, this is less brittle ; and 
doesn't add a lifetime of a trampoline context to extend the 
input delegate.

Jacob Carlborg <doob me.com> writes:

On 2018-09-16 16:12, Guillaume Piolat wrote:
 Anyone has any information about the ABI of delegates?
 
 In particular how to call them with a particular "this"/frame pointer?

You can explicitly set the context pointer of a delegate using the 
".ptr" property:

class Foo
{
     void bar() { }
}

void main()
{
     auto a = new Foo;
     void delegate () dg;
     dg.ptr = cast(void*) a;
     dg.funcptr = &Foo.bar;
     dg();
}

 To solve a hairy problem I need a delegate with a synthesized frame 
 pointer.
 https://dpaste.dzfl.pl/cf44417c98f9
 
 The problem is that delegate forwarding seems to require GC closures. I 
 want manually-managed closures.


-- 
/Jacob Carlborg