On Fri, 23 Aug 2024, 19:02 Iain Buclaw via Digitalmars-d, <digitalmars-d@puremagic.com> wrote:

On Friday, 23 August 2024 at 02:23:37 UTC, Nicholas Wilson wrote:
>
> GDC probably has something similar too.

https://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#index-_005f_005fbuiltin_005fexpect


Regarding DMD, I recall it being said that its code generator
always treats the true branch as the "likely" code path taken. So
if you have `if (cond) cold; else hot;`, invert the condition for
the benefit of DMD.

Yes, I understand, and this is part of my point here; that leads to really ugly code and deep nested scopes. That's what I've been doing, and I don't want my program to look like that. It's just bad software.

For instance, an extraordinarily common function pattern is to receive some inputs, validate a few things, and then do the thing at the end with valid inputs.

Validations are usually a series of exclusionary checks framed as `if(fails_validity_check) return;`

That flow keeps code in a nice linear flow, it doesn't introduce any scopes at all... but it's the opposite of what the assume(true) prediction rule wants. This is what lead me to this; almost every if statement I write is predicted wrong... and I definitely don't want to solve that by writing functions with 10 level deep nested scopes.