mirrors/z3
3
0
Fork 0
mirror of https://github.com/Z3Prover/z3 synced 2025-04-22 16:45:31 +00:00
Code Activity

enhance rewriting for indexof based on #3516

Browse source 
Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2020-03-25 13:29:36 -07:00
parent f92050c7e5
commit 73d73e6c95
1 changed files with 17 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

17
src/ast/rewriter/seq_rewriter.cpp
View file

@ -1138,6 +1138,23 @@ br_status seq_rewriter::mk_seq_index(expr* a, expr* b, expr* c, expr_ref& result
result = c;
return BR_DONE;
}
if (a == b) {
if (m_autil.is_numeral(c, r)) {
if (r.is_zero()) {
result = m_autil.mk_int(0);
}
else {
result = m_autil.mk_int(-1);
}
return BR_DONE;
}
else {
result = m().mk_ite(m().mk_eq(m_autil.mk_int(0), c), m_autil.mk_int(0), m_autil.mk_int(-1));
return BR_REWRITE2;
}
}
// Enhancement: walk segments of a, determine which segments must overlap, must not overlap, may overlap.
return BR_FAILED;
}