The Daily WTF

In modern times, there’s almost no reason to use Assembly, outside of highly specific and limited cases. For example, I recently worked on a project that uses a PRU, and while you can program that in C, I wanted to be able to count instructions so that I could get extremely precise timings to control LEDs.

In modern times, there’s also no reason to use Delphi, but Andre found this code a few years ago, and has been puzzling over it ever since.

procedure tvAdd(var a,b:timevectortype; Range: Integer); register; var i: Integer; pa,pb: PDouble; begin i:=succ(LongRec(Range).Lo-LongRec(Range).Hi); pa:=@a[LongRec(Range).Hi]; pb:=@b[LongRec(Range).Hi]; asm mov ecx, i mov eax, [pa] mov edx, [pb] @loop: fld qword ptr [eax] fadd qword ptr [edx] fstp qword ptr [eax] add eax,8 add edx,8 dec ecx jnz @loop wait end; { for i:=starts to ends do a[i] := a[i] + b[i]; } end;

The curly brackets at

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