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[Ada] Adapt ghost code to maintain proof

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gcc/ada/

	* libgnat/s-expmod.adb (Exp_Modular): Add assertions.
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Yannick Moy 2022-01-04 10:37:53 +01:00 committed by Pierre-Marie de Rodat
parent 42c54add83
commit 371b4ad7c4
1 changed files with 3 additions and 0 deletions
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3
gcc/ada/libgnat/s-expmod.adb
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@ -278,6 +278,7 @@ is
(Big (Result) * Big (Factor) ** (Exp - 1),
Big (Left) ** Right));
Lemma_Exp_Expand (Big (Factor), Exp - 1);
pragma Assert (Exp / 2 = (Exp - 1) / 2);
end if;
Lemma_Exp_Expand (Big (Factor), Exp);
@ -286,6 +287,8 @@ is
exit when Exp = 0;
Rest := Big (Factor) ** Exp;
pragma Assert (Equal_Modulo
(Big (Result) * (Rest * Rest), Big (Left) ** Right));
Lemma_Exp_Mod (Big (Factor) * Big (Factor), Exp, Big (Modulus));
pragma Assert
((Big (Factor) * Big (Factor)) ** Exp = Rest * Rest);