Consider this short program:
void main()
{
alias S = float;
S s1 = 0x1.24c92ep+5;
S s2 = -0x1.1c71c8p+0;
import std.math : std_pow = pow;
import core.stdc.stdio : printf;
import core.stdc.math: powf;
printf("std: %a\n", std_pow(s1, s2));
printf("pow: %a\n", s1 ^^ s2);
printf("pow: %a\n", powf(s1, s2));
version(LDC)
{
import ldc.intrinsics : llvm_pow;
printf("ldc: %a\n", llvm_pow(s1, s2));
}
}
std: 0x1.2c155ap-6
pow: 0x1.2c155ap-6
powf: 0x1.2c1558p-6
As you can see below the C powf compiles to the assembly powf and
LDC compiles to powf too. The output of std.math.pow is rather
large, hence not listed.
1) Is this a bug in Phobos or just a very annoying "feature"?
2) I thought that DMD was decoupled from Phobos? So I was very
astonished to see that it's not (see [1])
[1]
https://github.com/dlang/dmd/blob/master/src/expression.d#L14781
```
.text._Dmain segment
assume CS:.text._Dmain
_Dmain:
push RBP
mov RBP,RSP
sub RSP,010h
movss XMM0,FLAT:.rodata[00h][RIP]
movss -8[RBP],XMM0
movss XMM1,FLAT:.rodata[00h][RIP]
movss -4[RBP],XMM1
movss XMM1,-4[RBP]
movss XMM0,-8[RBP]
call powf@PC32
cvtss2sd XMM0,XMM0
mov EDI,offset FLAT:.rodata@32
mov AL,1
call printf@PC32
xor EAX,EAX
leave
ret
0f1f
add 0[RCX],AL
.text._Dmain ends
```
