diff options
| author | Andres Noetzli <andres.noetzli@gmail.com> | 2020-03-19 07:18:58 -0700 |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2020-03-19 09:18:58 -0500 |
| commit | 089a60266f2658e471d204fdd737e3e0d37e105c (patch) | |
| tree | dd07799cf5a1a06f184ce402fab016bf54c656e0 /src/theory/strings | |
| parent | 94844fbf4fbe4fa08d8fa4cbe093ba532f5bd613 (diff) | |
Only apply testConstStringInRegExp to const regexp (#4120)
Fixes #4070. `TheoryStringsRewriter::rewriteConcatRegExp()` rewrites
`(a)* ++ (_)*` to `(_)*`. To do so, it checks whether the elements
preceding `(_)*` match the empty string using
`TheoryStringsRewriter::testConstStringInRegExp()`. However, this method
only expects to be called on constant regular expressions (i.e. regular
expressions without string variables). This commit adds a corresponding
check before calling `TheoryStringsRewriter::testConstStringInRegExp()`.
Diffstat (limited to 'src/theory/strings')
| -rw-r--r-- | src/theory/strings/theory_strings_rewriter.cpp | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/src/theory/strings/theory_strings_rewriter.cpp b/src/theory/strings/theory_strings_rewriter.cpp index f05c9165b..95f537878 100644 --- a/src/theory/strings/theory_strings_rewriter.cpp +++ b/src/theory/strings/theory_strings_rewriter.cpp @@ -907,7 +907,7 @@ Node TheoryStringsRewriter::rewriteConcatRegExp(TNode node) { // if empty, drop it // e.g. this ensures we rewrite (_)* ++ (a)* ---> (_)* - if (testConstStringInRegExp(emptyStr, 0, curr)) + if (isConstRegExp(curr) && testConstStringInRegExp(emptyStr, 0, curr)) { curr = Node::null(); } @@ -928,7 +928,7 @@ Node TheoryStringsRewriter::rewriteConcatRegExp(TNode node) lastAllStar = true; // go back and remove empty ones from back of cvec // e.g. this ensures we rewrite (a)* ++ (_)* ---> (_)* - while (!cvec.empty() + while (!cvec.empty() && isConstRegExp(cvec.back()) && testConstStringInRegExp(emptyStr, 0, cvec.back())) { cvec.pop_back(); |