• Ilya Yaroshenko (21/21) Jun 23 2014 Hello all!
• John Colvin (5/26) Jun 23 2014 If you look at the bottom of those _array functions you will find
• Ilya Yaroshenko (1/5) Jun 23 2014 I think it is something different. LDC has standard D inline asm.
• Kai Nacke (22/43) Jun 24 2014 Hi Ilya,

"Ilya Yaroshenko" <ilyayaroshenko gmail.com> writes:

Hello all!

very simple code:

------------------
double[] a, c;
...
c[] += a[];
------------------

The DMD version I can find in _arraySliceSliceAddass_d, 
https://github.com/D-Programming-Language/druntime/blob/master/
rc/rt/arraydouble.d 
.

What about LDC and GDC?
The _arraySliceSliceAddass_d is the same, no any version(LDC).

When I compile code into assembler I found other code then in asm 
scope.

So I suppose LDC has it's own architecture.
Is it right?

Where I can find it for understanding what optimization can be 
done by LLVM optimizer?

Have GDC it's own architecture too?

Best Regards,
Ilya

"John Colvin" <john.loughran.colvin gmail.com> writes:

On Monday, 23 June 2014 at 18:09:46 UTC, Ilya Yaroshenko wrote:
 Hello all!

 very simple code:

 ------------------
 double[] a, c;
 ...
 c[] += a[];
 ------------------

 The DMD version I can find in _arraySliceSliceAddass_d, 
 https://github.com/D-Programming-Language/druntime/blob/master/
rc/rt/arraydouble.d 
 .

 What about LDC and GDC?
 The _arraySliceSliceAddass_d is the same, no any version(LDC).

 When I compile code into assembler I found other code then in 
 asm scope.

 So I suppose LDC has it's own architecture.
 Is it right?

 Where I can find it for understanding what optimization can be 
 done by LLVM optimizer?

 Have GDC it's own architecture too?

 Best Regards,
 Ilya

If you look at the bottom of those _array functions you will find 
a regular loop doing the cleanup for anything missed by the 
inline asm. If I remember correctly, for gdc it is this loop 
doing the whole operation as the asm is versioned out.

"Ilya Yaroshenko" <ilyayaroshenko gmail.com> writes:

 If you look at the bottom of those _array functions you will 
 find a regular loop doing the cleanup for anything missed by 
 the inline asm. If I remember correctly, for gdc it is this 
 loop doing the whole operation as the asm is versioned out.

I think it is something different. LDC has standard D inline asm.

"Kai Nacke" <kai redstar.de> writes:

On Monday, 23 June 2014 at 18:09:46 UTC, Ilya Yaroshenko wrote:
 Hello all!

 very simple code:

 ------------------
 double[] a, c;
 ...
 c[] += a[];
 ------------------

 The DMD version I can find in _arraySliceSliceAddass_d, 
 https://github.com/D-Programming-Language/druntime/blob/master/
rc/rt/arraydouble.d 
 .

 What about LDC and GDC?
 The _arraySliceSliceAddass_d is the same, no any version(LDC).

 When I compile code into assembler I found other code then in 
 asm scope.

 So I suppose LDC has it's own architecture.
 Is it right?

 Where I can find it for understanding what optimization can be 
 done by LLVM optimizer?

 Have GDC it's own architecture too?

 Best Regards,
 Ilya

Hi Ilya,

I am not sure if I understand your question. I compiled this code 
with ldc

void main()
{
     double[] a, c;

     a[] = 1;
     c[] = 2;
     c[] += a[];
}

(options ldc2 -c -output-ll -output-s -release -O0)

and get in the main function

	movq	120(%rsp), %r8
	movq	128(%rsp), %r9
	movq	104(%rsp), %rcx
	movq	112(%rsp), %rdx
	callq	_arraySliceSliceAddass_d

Using -O1 or higher optimizes the call away, maybe that is the 
problem. Could you post the source code you are using?

Regards,
Kai