Re: Erlang JIT and loaded code

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Thanks for the answer, Lukas.

Giving a bit more context: I'm doing a benchmarking research on Erlang JIT,
similar to what ErLLVM did.

I managed to get the code size (I suppose) from internal structures:

   - erl_module_instance->code_length (for emulator and asm)
   - erl_module_instance->hipe_code->text_segment_size (for HiPE and ErLLVM=
)

Does that make sense or are those values unrelated?

Em seg., 25 de abr. de 2022 =C3=A0s 06:13, Lukas Larsson <[email protected]>
escreveu:

> Hello!
>
> On Tue, Apr 19, 2022 at 7:17 AM Vitor Rocha <[email protected]> wrote:
>
>> (1) how do I know if my code is actually being executed as interpreted o=
r
>> native?
>>
>
> All code loaded from .beam files are run natively if the VM supports JIT
> compilation.
>
>
>> (2) If I compile a module inside Erlang's shell, using the `c:c/1`
>> function, is the module going to be compiled to native too? Will its
>> execution be switched to native?
>>
>
> There is no difference in how it is compiled, it will always be translate=
d
> into native code when loaded.
>
>
>> (3) Where is stored the generated beamasm native code? I would like to
>> get its size in bytes?
>>
>
> It is stored in memory of the VM. You can get a file dump of the native
> code by passing `+JDdump true` when starting `erl`. There is no way to ge=
t
> the loaded memory size of a single module, but you can get a relatively
> close value by checking what `erlang:memory(code)` returns before and aft=
er
> the module is loaded.
>
>
>>
>> --
>> Atenciosamente,
>> Vitor Rocha da Silva
>>
>

--=20
Atenciosamente,
Vitor Rocha da Silva

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<div dir=3D"ltr"><div>Thanks for the answer, Lukas.<br></div><div><br></div=
><div>Giving a bit more context: I&#39;m doing a benchmarking research on E=
rlang JIT, similar to what ErLLVM did.<br></div><div><br></div><div>I manag=
ed to get the code size (I suppose) from internal structures:<br><ul><li>er=
l_module_instance-&gt;code_length (for emulator and asm)</li><li>erl_module=
_instance-&gt;hipe_code-&gt;text_segment_size (for HiPE and ErLLVM)</li></u=
l><div>Does that make sense or are those values unrelated?<br></div></div><=
/div><br><div class=3D"gmail_quote"><div dir=3D"ltr" class=3D"gmail_attr">E=
m seg., 25 de abr. de 2022 =C3=A0s 06:13, Lukas Larsson &lt;<a href=3D"mail=
to:[email protected]">[email protected]</a>&gt; escreveu:<br></div><blockquot=
e class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px s=
olid rgb(204,204,204);padding-left:1ex"><div dir=3D"ltr"><div>Hello!</div><=
br><div class=3D"gmail_quote"><div dir=3D"ltr" class=3D"gmail_attr">On Tue,=
 Apr 19, 2022 at 7:17 AM Vitor Rocha &lt;<a href=3D"mailto:vitor.vrs@gmail.=
com" target=3D"_blank">[email protected]</a>&gt; wrote:<br></div><blockqu=
ote class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px=
 solid rgb(204,204,204);padding-left:1ex"><div dir=3D"ltr"><div>(1) how do =
I know if my code is actually being executed as interpreted or native?</div=
></div></blockquote><div><br></div><div>All code loaded from .beam files ar=
e run natively if the VM supports JIT compilation.</div><div>=C2=A0</div><b=
lockquote class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;border-le=
ft:1px solid rgb(204,204,204);padding-left:1ex"><div dir=3D"ltr"><div>(2) I=
f I compile a module inside Erlang&#39;s shell, using the `c:c/1` function,=
 is the module going to be compiled to native too? Will its execution be sw=
itched to native?<br></div></div></blockquote><div><br></div><div>There is =
no=C2=A0difference in how it is compiled, it will always be translated into=
 native code when loaded.</div><div>=C2=A0</div><blockquote class=3D"gmail_=
quote" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,=
204);padding-left:1ex"><div dir=3D"ltr"><div></div><div>(3) Where is stored=
 the generated beamasm native code? I would like to get its size in bytes?<=
br></div></div></blockquote><div><br></div><div>It is stored in memory of t=
he VM. You can get a file dump of the native code by passing `+JDdump true`=
 when starting `erl`. There is no way to get the loaded memory size of a si=
ngle module, but you can get a relatively close value by checking what `erl=
ang:memory(code)` returns before and after the module is loaded.</div><div>=
=C2=A0</div><blockquote class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0=
.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir=3D"l=
tr"><div><br></div><div>-- <br><div dir=3D"ltr"><span style=3D"font-family:=
&quot;trebuchet ms&quot;,sans-serif">Atenciosamente,<br>Vitor Rocha da Silv=
a</span><br></div></div></div>
</blockquote></div></div>
</blockquote></div><br clear=3D"all"><br>-- <br><div dir=3D"ltr" class=3D"g=
mail_signature"><span style=3D"font-family:trebuchet ms,sans-serif">Atencio=
samente,<br>Vitor Rocha da Silva</span><br></div>

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