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digitalmars.D - Can someone decipher this moon speak for me? (abi - calling

reply "Bernard Helyer" <b.helyer gmail.com> writes:
http://dlang.org/abi.html

"The extern (C) and extern (D) calling convention matches the C 
calling convention used by the supported C compiler on the host 
system. Except that the extern (D) calling convention for Windows 
x86 is described here."

Was this written by someone slamming their face onto the keyboard 
repeatedly? Is the calling convention just C on non-windows 
platforms? What about AMD64? Why should I, as someone writing a D 
implementation, burn cycles on trying to decypher this madness? 
Didn't this section _used_ to make sense?

To summarise:





fucking what?






</rant>
Feb 29 2012
parent reply "Bernard Helyer" <b.helyer gmail.com> writes:
So as near as I can tell, it's trying to say

"On non-Windows platforms, both extern (C) and extern (D) match 
the calling convention of the platforms C compiler. On Windows,  
the extern (D) calling convention differs, and is documented 
below:"

Is this accurate?

If so, there's is no way I am wasting my time with the D calling 
convention. I'm not wrangling LLVM into producing DM OMF, so 
binary compatibility isn't going to happen anyway.

If not, then I have no idea.
Feb 29 2012
parent reply "Martin Nowak" <dawg dawgfoto.de> writes:
On Thu, 01 Mar 2012 06:26:28 +0100, Bernard Helyer <b.helyer gmail.com>  
wrote:


 So as near as I can tell, it's trying to say

 "On non-Windows platforms, both extern (C) and extern (D) match the  
 calling convention of the platforms C compiler. On Windows,  the extern  
 (D) calling convention differs, and is documented below:"

 Is this accurate?

 If so, there's is no way I am wasting my time with the D calling  
 convention. I'm not wrangling LLVM into producing DM OMF, so binary  
 compatibility isn't going to happen anyway.

 If not, then I have no idea.


For x86-32 dmd uses a fastcall, where EAX can contain a parameter, for  
Windows AND all other supported OSes.
This is different from cdecl where parameters are always passed on the  
stack.

For x86-64 D follows the SysV AMD64 ABI, don't know about Windows.
Feb 29 2012
next sibling parent reply "Bernard Helyer" <b.helyer gmail.com> writes:
On Thursday, 1 March 2012 at 06:07:40 UTC, Martin Nowak wrote:

 For x86-32 dmd uses a fastcall, where EAX can contain a 
 parameter, for Windows AND all other supported OSes.


._.;

Well, that's nice to know, thanks. Because we (SDC) use fastcall 
for D, just (we thought) as a temporary measure.

But seriously, I don't think one can gather that information even 
if they can recognise fastcall from the technical description.
Feb 29 2012
parent "Martin Nowak" <dawg dawgfoto.de> writes:
On Thu, 01 Mar 2012 07:14:17 +0100, Bernard Helyer <b.helyer gmail.com>  
wrote:


 On Thursday, 1 March 2012 at 06:07:40 UTC, Martin Nowak wrote:

 For x86-32 dmd uses a fastcall, where EAX can contain a parameter, for  
 Windows AND all other supported OSes.


 ._.;

 Well, that's nice to know, thanks. Because we (SDC) use fastcall for D,  
 just (we thought) as a temporary measure.

 But seriously, I don't think one can gather that information even if  
 they can recognise fastcall from the technical description.


Be aware though, that fastcall means vendor specific,
so LLVM's understanding of fastcall could be different.
Mar 01 2012
prev sibling parent Jacob Carlborg <doob me.com> writes:
On 2012-03-01 07:07, Martin Nowak wrote:

 On Thu, 01 Mar 2012 06:26:28 +0100, Bernard Helyer <b.helyer gmail.com>
 wrote:


 So as near as I can tell, it's trying to say

 "On non-Windows platforms, both extern (C) and extern (D) match the
 calling convention of the platforms C compiler. On Windows, the extern
 (D) calling convention differs, and is documented below:"

 Is this accurate?

 If so, there's is no way I am wasting my time with the D calling
 convention. I'm not wrangling LLVM into producing DM OMF, so binary
 compatibility isn't going to happen anyway.

 If not, then I have no idea.


 For x86-32 dmd uses a fastcall, where EAX can contain a parameter, for
 Windows AND all other supported OSes.


 From the documentation it sounds like it's ONLY on Windows.


 This is different from cdecl where parameters are always passed on the
 stack.

 For x86-64 D follows the SysV AMD64 ABI, don't know about Windows.



-- 
/Jacob Carlborg
Feb 29 2012