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Date: Tue, 23 Feb 2021 10:10:09 -0800 (PST)
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Subject: Implementation of arrays in Ada compilers.
From: Vincent DIEMUNSCH <vincent.diemunsch@gmail.com>
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Xref: reader02.eternal-september.org comp.lang.ada:61427
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Hello,

I would like to know what is the runtime implementation of arrays used by c=
ompilers, and GNAT in particular.

Does an array is represented as an address, a starting index (First) and an=
 ending index (Last) ? Or a First index and a Length.
Is the address the A=E2=80=99First=E2=80=99Address ?
And what about slicing ? Is the address modified ?
And what about passing arrays as reference ?
And what happens when the array is a component of a record :
type OneString (Length : Integer) is
   record
        Data :=E2=80=AFString(1 .. Length);
   end record;

Is this optimized as a special kind of arrays ?

Is there a paper that discusses these implementation choices ?


Regards,

Vincent