GCC builtins in LDC - compiler interoperability

[Cecil Ward]

On Thursday, 16 July 2020 at 00:12:06 UTC, kinke wrote:
> On Thursday, 16 July 2020 at 00:06:49 UTC, kinke wrote:
>> With -O, bar() is optimized to a `return 123`.
>
> (After the foo() call due to potential side effects.)

This is just what I have been working on : an assume() routine 
which modifies the compiler’s behaviour so that later code 
generation is optimised further by the knowledge gained by 
declarations of truths in assume( cond ) statements. Now you’ve 
been kind enough to give me the missing piece for ldc, I can add 
LDC support in too next.

Thank you so very much for your generous help guys. I’m an 
experienced professional asm and C programmer but I’m just 
starting out with D, and due to my poor health my memory and 
concentration are shot.