• rempas (2/2) Nov 11 2021 I've seen from
• Adam D Ruppe (3/5) Nov 11 2021 You really shouldn't expect dmd to inline *anything*.
• rempas (2/5) Nov 11 2021 Oh yeah! I just thought to ask anyway! Thanks a lot for your time!
• Basile B. (10/12) Nov 11 2021 Yes, this is still the case. A particularity of DMD inliner is
• rempas (3/13) Nov 11 2021 What? Not even GCC or Clang? Someone said that LDC2 does it with
• max haughton (2/18) Nov 11 2021 There's an attribute to tell it the function is safe to inline.
• rempas (2/3) Nov 12 2021 And can't you do that with inline asm?
• max haughton (3/8) Nov 12 2021 Not always. The attribute is intended for naked asm since
• rempas (2/4) Nov 12 2021 Got that! Thanks for the info!
• Elronnd (3/4) Nov 11 2021 GCC can do it. Somewhat notoriously, LTO can lead to bugs from
• rempas (3/5) Nov 12 2021 That's really interesting to hear! Do we have any cases where
• Basile B. (3/8) Nov 13 2021 I have missed the LTO train TBH, gotta try that once...
• Guillaume Piolat (3/7) Nov 14 2021 LDC can also do it with GCC asm constraints, however it is

rempas <rempas tutanota.com> writes:

I've seen from 
[this](https://forum.dlang.org/post/op.vrzngqeavxi10f biotronic-laptop) reply
in a thread from 2011 that DMD will not inline functions that contain inline
assembly. Is this still the case?

Adam D Ruppe <destructionator gmail.com> writes:

On Thursday, 11 November 2021 at 08:58:43 UTC, rempas wrote:
 I've seen from 
 [this](https://forum.dlang.org/post/op.vrzngqeavxi10f biotronic-laptop) reply
in a thread from 2011 that DMD will not inline functions that contain inline
assembly. Is this still the case?

You really shouldn't expect dmd to inline *anything*.

Or to optimize anything for that matter. That isn't its strength.

rempas <rempas tutanota.com> writes:

On Thursday, 11 November 2021 at 12:05:14 UTC, Adam D Ruppe wrote:
 You really shouldn't expect dmd to inline *anything*.

 Or to optimize anything for that matter. That isn't its 
 strength.

Oh yeah! I just thought to ask anyway! Thanks a lot for your time!

Basile B. <b2.temp gmx.com> writes:

On Thursday, 11 November 2021 at 08:58:43 UTC, rempas wrote:
 I've seen from 
 [this](https://forum.dlang.org/post/op.vrzngqeavxi10f biotronic-laptop) reply
in a thread from 2011 that DMD will not inline functions that contain inline
assembly. Is this still the case?

Yes, this is still the case. A particularity of DMD inliner is 
that it does its job in the front-end, so inlining asm is totally 
impossible. Then, even if inlining was done in the backend 
inlining of asm would not be guaranteed because the byte code is 
generated at a very late stag, which causes problem with the 
registry allocator, the preservation of the stack, etc.

For example ldc2 does not inline a trival asm func 
https://godbolt.org/z/1W6r693Tq.

As for now, I know no compiler that can do that.

rempas <rempas tutanota.com> writes:

On Thursday, 11 November 2021 at 13:22:15 UTC, Basile B. wrote:
 Yes, this is still the case. A particularity of DMD inliner is 
 that it does its job in the front-end, so inlining asm is 
 totally impossible. Then, even if inlining was done in the 
 backend inlining of asm would not be guaranteed because the 
 byte code is generated at a very late stag, which causes 
 problem with the registry allocator, the preservation of the 
 stack, etc.

 For example ldc2 does not inline a trival asm func 
 https://godbolt.org/z/1W6r693Tq.

 As for now, I know no compiler that can do that.

What? Not even GCC or Clang? Someone said that LDC2 does it with 
two ways in the thread I linked

max haughton <maxhaton gmail.com> writes:

On Thursday, 11 November 2021 at 17:29:33 UTC, rempas wrote:
 On Thursday, 11 November 2021 at 13:22:15 UTC, Basile B. wrote:
 Yes, this is still the case. A particularity of DMD inliner is 
 that it does its job in the front-end, so inlining asm is 
 totally impossible. Then, even if inlining was done in the 
 backend inlining of asm would not be guaranteed because the 
 byte code is generated at a very late stag, which causes 
 problem with the registry allocator, the preservation of the 
 stack, etc.

 For example ldc2 does not inline a trival asm func 
 https://godbolt.org/z/1W6r693Tq.

 As for now, I know no compiler that can do that.

 What? Not even GCC or Clang? Someone said that LDC2 does it 
 with two ways in the thread I linked

There's an attribute to tell it the function is safe to inline.

rempas <rempas tutanota.com> writes:

On Thursday, 11 November 2021 at 19:22:33 UTC, max haughton wrote:
 There's an attribute to tell it the function is safe to inline.

And can't you do that with inline asm?

max haughton <maxhaton gmail.com> writes:

On Friday, 12 November 2021 at 11:32:16 UTC, rempas wrote:
 On Thursday, 11 November 2021 at 19:22:33 UTC, max haughton 
 wrote:
 There's an attribute to tell it the function is safe to inline.

 And can't you do that with inline asm?

Not always. The attribute is intended for naked asm since 
inlining could be completely wrong in this case.

rempas <rempas tutanota.com> writes:

On Friday, 12 November 2021 at 15:10:19 UTC, max haughton wrote:
 Not always. The attribute is intended for naked asm since 
 inlining could be completely wrong in this case.

Got that! Thanks for the info!

Elronnd <elronnd elronnd.net> writes:

On Thursday, 11 November 2021 at 13:22:15 UTC, Basile B. wrote:
 As for now, I know no compiler that can do that.

GCC can do it.  Somewhat notoriously, LTO can lead to bugs from 
underspecified asm constraints following cross-TU inlining.

rempas <rempas tutanota.com> writes:

On Friday, 12 November 2021 at 00:46:05 UTC, Elronnd wrote:
 GCC can do it.  Somewhat notoriously, LTO can lead to bugs from 
 underspecified asm constraints following cross-TU inlining.

That's really interesting to hear! Do we have any cases where 
this happened to software that was used for production?

Basile B. <b2.temp gmx.com> writes:

On Friday, 12 November 2021 at 00:46:05 UTC, Elronnd wrote:
 On Thursday, 11 November 2021 at 13:22:15 UTC, Basile B. wrote:
 As for now, I know no compiler that can do that.

 GCC can do it.  Somewhat notoriously,

you meant "infamously" ?

 LTO can lead to bugs from underspecified asm constraints 
 following cross-TU inlining.

I have missed the LTO train TBH, gotta try that once...

Guillaume Piolat <first.last gmail.com> writes:

On Friday, 12 November 2021 at 00:46:05 UTC, Elronnd wrote:
 On Thursday, 11 November 2021 at 13:22:15 UTC, Basile B. wrote:
 As for now, I know no compiler that can do that.

 GCC can do it.  Somewhat notoriously, LTO can lead to bugs from 
 underspecified asm constraints following cross-TU inlining.

LDC can also do it with GCC asm constraints, however it is 
atrociously hard to get documentation and examples for this.