Did Walter's pure optimization ever make it into dmd?

[ag0aep6g]

On 04/02/2018 10:52 AM, Dennis wrote:
> ```For these examples, I'll use the D programming language compiler that 
> is currently under development. (...)
> But what if bar is pure?
> 
> pure int bar(int);
> 
> int foo(int i)
> {
>      return bar(i) + bar(i);
> }
> 
> Now the assembler output is:
> 
>      push    EAX    ; save argument i on stack
>      call    bar    ; call bar(i)
>      add     EAX,EAX   ; double result
>      pop     ECX    ; clean stack
>      ret      ; return to caller
> 
> bar(i) is called only once```
> 
> I've checked whether multiple calls to pure functions get optimized, and 
> it seems like they *never* do. I've tried different versions of dmd with 
> optimizaiton flags on/off, and also LDC/GDC.

The function also needs the `nothrow` attribute. And you have to compile 
with `-O -release`.

https://run.dlang.io/is/GWnUPH