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Diffstat (limited to 'lib/Integers.v')
| -rw-r--r-- | lib/Integers.v | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/lib/Integers.v b/lib/Integers.v index cbbf28c..d85007b 100644 --- a/lib/Integers.v +++ b/lib/Integers.v @@ -2454,6 +2454,19 @@ Proof. generalize wordsize_pos; generalize wordsize_max_unsigned; omega. Qed. +Theorem ror_rol_neg: + forall x y, (zwordsize | modulus) -> ror x y = rol x (neg y). +Proof. + intros. apply same_bits_eq; intros. + rewrite bits_ror by auto. rewrite bits_rol by auto. + f_equal. apply eqmod_mod_eq. omega. + apply eqmod_trans with (i - (- unsigned y)). + apply eqmod_refl2; omega. + apply eqmod_sub. apply eqmod_refl. + apply eqmod_divides with modulus. + apply eqm_unsigned_repr. auto. +Qed. + Theorem or_ror: forall x y z, ltu y iwordsize = true -> |