A small comparison

[bearophile]

jerro:

> If I use core.stdc.math.sin and compile the code with:
>
> gdc c.d -o c -O3 -fno-bounds-check -frelease
>
> I get:
>
>   404e80:	cvtsi2sd %ebx,%xmm0
>   404e84:	callq  403070 <sin at plt>
>   404e89:	mulsd  %xmm0,%xmm0
>   404e8d:	add    $0x1,%ebx
>   404e90:	cmp    $0x64,%ebx
>   404e93:	addsd  0x28(%rsp),%xmm0
>   404e99:	movsd  %xmm0,0x28(%rsp)
>   404e9f:	jne    404e80 <_Dmain+0x60>
>
> This is almost exactly the same code as
>
>> .L3:
>>    cvtsi2sd    %ebx, %xmm0
>>    call    sin
>> .L2:
>>    mulsd   %xmm0, %xmm0
>>    addl    $1, %ebx
>>    cmpl    $100, %ebx
>>    addsd   8(%rsp), %xmm0
>>    movsd   %xmm0, 8(%rsp)
>>    jne .L3

I guess the back-end is very similar, and it's able to optimize 
the code well :-)

What's the difference between std.math.sin and core.stdc.math.sin?

Bye,
bearophile