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| author | Andrew Reynolds <andrew.j.reynolds@gmail.com> | 2019-10-06 02:33:25 -0500 |
|---|---|---|
| committer | Andres Noetzli <andres.noetzli@gmail.com> | 2019-10-06 00:33:25 -0700 |
| commit | 51f9809788e4d26a423d9812ceab0f6720550c1b (patch) | |
| tree | 59c233fd8b18afa6ae3f2e6797f405de7417de5b /src/theory/strings | |
| parent | 472c5a592c78e4757b3201f9e20908a4c645921b (diff) | |
Fix str to int reduction (#3358)
This fixes a corner case of the str-to-int reduction for the case where the argument is the empty string.
This fixes #3357.
Diffstat (limited to 'src/theory/strings')
| -rw-r--r-- | src/theory/strings/theory_strings_preprocess.cpp | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/src/theory/strings/theory_strings_preprocess.cpp b/src/theory/strings/theory_strings_preprocess.cpp index d1eef656b..8e057a525 100644 --- a/src/theory/strings/theory_strings_preprocess.cpp +++ b/src/theory/strings/theory_strings_preprocess.cpp @@ -309,6 +309,9 @@ Node StringsPreprocess::simplify( Node t, std::vector< Node > &new_nodes ) { lem = s.eqNode(nm->mkNode(APPLY_UF, us, d_zero)); conc2.push_back(lem); + lem = nm->mkNode(GT, lens, d_zero); + conc2.push_back(lem); + Node x = nm->mkBoundVar(nm->integerType()); Node xbv = nm->mkNode(BOUND_VAR_LIST, x); Node g = @@ -343,6 +346,7 @@ Node StringsPreprocess::simplify( Node t, std::vector< Node > &new_nodes ) { // ELSE: // stoit = U( len( s ) ) ^ U( 0 ) = 0 ^ // "" = Us( len( s ) ) ^ s = Us( 0 ) ^ + // str.len( s ) > 0 ^ // forall x. (x>=0 ^ x < str.len(s)) => // Us( x ) = Ud( x ) ++ Us( x+1 ) ^ // U( x+1 ) = ( str.code( Ud( x ) ) - 48 ) + 10*U( x ) |