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| author | xleroy <xleroy@fca1b0fc-160b-0410-b1d3-a4f43f01ea2e> | 2013-12-20 13:05:53 +0000 |
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| committer | xleroy <xleroy@fca1b0fc-160b-0410-b1d3-a4f43f01ea2e> | 2013-12-20 13:05:53 +0000 |
| commit | 7698300cfe2d3f944ce2e1d4a60a263620487718 (patch) | |
| tree | 74292bb5f65bc797906b5c768df2e2e937e869b6 /lib/Integers.v | |
| parent | c511207bd0f25c4199770233175924a725526bd3 (diff) | |
| download | compcert-7698300cfe2d3f944ce2e1d4a60a263620487718.tar.gz compcert-7698300cfe2d3f944ce2e1d4a60a263620487718.zip | |
Merge of branch value-analysis.
git-svn-id: https://yquem.inria.fr/compcert/svn/compcert/trunk@2381 fca1b0fc-160b-0410-b1d3-a4f43f01ea2e
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 cbbf28c7..d85007b4 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 -> |