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| author | Xavier Leroy <xavier.leroy@college-de-france.fr> | 2020-02-18 16:57:17 +0100 |
|---|---|---|
| committer | Xavier Leroy <xavierleroy@users.noreply.github.com> | 2020-02-21 13:29:39 +0100 |
| commit | be0b1872bf2ad36df9b0c7a0ffa63b9e77fa769b (patch) | |
| tree | 0d54cce547d12567d7e9e9f2c4d650e5a1b94b39 /backend/Tailcallproof.v | |
| parent | a9eaf4897c825093aba2137ff76e56bfbf1e72d5 (diff) | |
| download | compcert-kvx-be0b1872bf2ad36df9b0c7a0ffa63b9e77fa769b.tar.gz compcert-kvx-be0b1872bf2ad36df9b0c7a0ffa63b9e77fa769b.zip | |
Refine the type of function results in AST.signature
Before it was "option typ". Now it is a proper inductive type
that can also express small integer types (8/16-bit unsigned/signed integers).
One benefit is that external functions get more precise types that
control better their return values. As a consequence,
the CompCert C type preservation property now holds unconditionally,
without extra typing hypotheses on external functions.
Diffstat (limited to 'backend/Tailcallproof.v')
| -rw-r--r-- | backend/Tailcallproof.v | 10 |
1 files changed, 4 insertions, 6 deletions
diff --git a/backend/Tailcallproof.v b/backend/Tailcallproof.v index 06e314f3..9ec89553 100644 --- a/backend/Tailcallproof.v +++ b/backend/Tailcallproof.v @@ -157,12 +157,10 @@ Lemma transf_instr_charact: transf_instr_spec f instr (transf_instr f pc instr). Proof. intros. unfold transf_instr. destruct instr; try constructor. - caseEq (is_return niter f n r && tailcall_is_possible s && - opt_typ_eq (sig_res s) (sig_res (fn_sig f))); intros. - destruct (andb_prop _ _ H0). destruct (andb_prop _ _ H1). - eapply transf_instr_tailcall; eauto. - eapply is_return_charact; eauto. - constructor. + destruct (is_return niter f n r && tailcall_is_possible s && + rettype_eq (sig_res s) (sig_res (fn_sig f))) eqn:B. +- InvBooleans. eapply transf_instr_tailcall; eauto. eapply is_return_charact; eauto. +- constructor. Qed. Lemma transf_instr_lookup: |