diff options
author | Andres Noetzli <noetzli@stanford.edu> | 2019-05-14 12:06:41 -0700 |
---|---|---|
committer | Andres Noetzli <noetzli@stanford.edu> | 2019-05-14 13:41:46 -0700 |
commit | b6dbe3d31271bd7aaccd3d0bb1ea748b323a715a (patch) | |
tree | d8d3bf0bbbb244ea1349f6035594afeb67fc100c | |
parent | 3b407342c06d89910e19373e3c486155464843a7 (diff) |
Fix model of Boolean vars with eager bit-blaster
When bit-blasting eagerly, we were not assigning values to the Boolean
variables in the `TheoryModel`. With eager bit-blasting, the BV SAT
solver gets all (converted) terms, including the Boolean ones, so
`EagerBitblaster::collectModelInfo()` is responsible for assigning
values to Boolean variables. However, it has only been assigning values
to bit-vector variables, which lead to wrong models. This commit fixes
the issue by asking the `CnfStream` for the Boolean variables, querying
the SAT solver for their value, and assigning them in the `TheoryModel`.
-rw-r--r-- | src/theory/bv/bitblast/eager_bitblaster.cpp | 32 | ||||
-rw-r--r-- | test/regress/CMakeLists.txt | 1 | ||||
-rw-r--r-- | test/regress/regress0/bv/bool-model.smt2 | 7 |
3 files changed, 40 insertions, 0 deletions
diff --git a/src/theory/bv/bitblast/eager_bitblaster.cpp b/src/theory/bv/bitblast/eager_bitblaster.cpp index 77ff6f885..3527f3855 100644 --- a/src/theory/bv/bitblast/eager_bitblaster.cpp +++ b/src/theory/bv/bitblast/eager_bitblaster.cpp @@ -241,6 +241,9 @@ Node EagerBitblaster::getModelFromSatSolver(TNode a, bool fullModel) { bool EagerBitblaster::collectModelInfo(TheoryModel* m, bool fullModel) { + NodeManager* nm = NodeManager::currentNM(); + + // Collect the values for the bit-vector variables TNodeSet::iterator it = d_variables.begin(); for (; it != d_variables.end(); ++it) { TNode var = *it; @@ -262,6 +265,35 @@ bool EagerBitblaster::collectModelInfo(TheoryModel* m, bool fullModel) } } } + + // Collect the values for the Boolean variables + std::vector<TNode> vars; + d_cnfStream->getBooleanVariables(vars); + for (TNode var : vars) + { + Node const_value; + + if (d_cnfStream->hasLiteral(var)) + { + prop::SatLiteral bit = d_cnfStream->getLiteral(var); + prop::SatValue bit_value = d_satSolver->value(bit); + Assert(bit_value != prop::SAT_VALUE_UNKNOWN); + const_value = nm->mkConst(bit_value == prop::SAT_VALUE_TRUE); + } + else + { + if (!fullModel) + { + continue; + } + const_value = nm->mkConst(false); + } + + if (!m->assertEquality(var, const_value, true)) + { + return false; + } + } return true; } diff --git a/test/regress/CMakeLists.txt b/test/regress/CMakeLists.txt index 2f39bbb59..98b12e1a6 100644 --- a/test/regress/CMakeLists.txt +++ b/test/regress/CMakeLists.txt @@ -161,6 +161,7 @@ set(regress_0_tests regress0/bv/ackermann4.smt2 regress0/bv/bool-to-bv-all.smt2 regress0/bv/bool-to-bv-ite.smt2 + regress0/bv/bool-model.smt2 regress0/bv/bug260a.smt regress0/bv/bug260b.smt regress0/bv/bug440.smt diff --git a/test/regress/regress0/bv/bool-model.smt2 b/test/regress/regress0/bv/bool-model.smt2 new file mode 100644 index 000000000..30531418c --- /dev/null +++ b/test/regress/regress0/bv/bool-model.smt2 @@ -0,0 +1,7 @@ +; COMMAND-LINE: --bitblast=eager +(set-info :status sat) +(set-logic QF_BV) +(declare-fun x () Bool) +(declare-fun y () Bool) +(assert (xor y x)) +(check-sat) |