replaced simplifier with rewriter at pull_quant.cpp

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>

scripts/mk_project.py

@@ -30,7 +30,7 @@ def init_project_def():
     # Simplifier module will be deleted in the future.
     # It has been replaced with rewriter module.
     add_lib('simplifier', ['rewriter', 'front_end_params'], 'ast/simplifier')
-    add_lib('normal_forms', ['rewriter', 'simplifier'], 'ast/normal_forms')
+    add_lib('normal_forms', ['rewriter', 'front_end_params'], 'ast/normal_forms')
     add_lib('core_tactics', ['tactic', 'normal_forms'], 'tactic/core')
     add_lib('sat_tactic', ['tactic', 'sat'], 'sat/tactic')
     add_lib('arith_tactics', ['core_tactics', 'sat'], 'tactic/arith')
@@ -41,7 +41,7 @@ def init_project_def():
     add_lib('cmd_context', ['solver', 'rewriter'])
     add_lib('extra_cmds', ['cmd_context', 'subpaving_tactic', 'arith_tactics'], 'cmd_context/extra_cmds')
     add_lib('smt2parser', ['cmd_context', 'parser_util'], 'parsers/smt2')
-    add_lib('pattern', ['normal_forms', 'smt2parser'], 'ast/pattern')
+    add_lib('pattern', ['normal_forms', 'smt2parser', 'simplifier'], 'ast/pattern')
     add_lib('macros', ['simplifier', 'front_end_params'], 'ast/macros')
     add_lib('proof_checker', ['rewriter', 'front_end_params'], 'ast/proof_checker')
     add_lib('bit_blaster', ['rewriter', 'simplifier', 'front_end_params'], 'ast/rewriter/bit_blaster')

src/ast/normal_forms/cnf.cpp

@@ -16,8 +16,9 @@ Author:
 Revision History:
 
 --*/
-
 #include"cnf.h"
+#include"var_subst.h"
+#include"ast_util.h"
 #include"ast_pp.h"
 #include"ast_ll_pp.h"
 

src/ast/normal_forms/pull_quant.cpp

@@ -17,10 +17,22 @@ Notes:
 
 --*/
 #include"pull_quant.h"
+#include"var_subst.h"
+#include"rewriter_def.h"
 #include"ast_pp.h"
-#include"for_each_expr.h"
 
-void pull_quant::pull_quant1(func_decl * d, unsigned num_children, expr * const * children, expr_ref & result) {
+struct pull_quant::imp {
+    
+    struct rw_cfg : public default_rewriter_cfg {
+        ast_manager & m_manager;
+        shift_vars    m_shift;
+        
+        rw_cfg(ast_manager & m):
+            m_manager(m), 
+            m_shift(m) {
+        }
+
+        bool pull_quant1_core(func_decl * d, unsigned num_children, expr * const * children, expr_ref & result) {
             ptr_buffer<sort>  var_sorts;
             buffer<symbol>    var_names;
             symbol            qid;
@@ -38,11 +50,11 @@ void pull_quant::pull_quant1(func_decl * d, unsigned num_children, expr * const
                     quantifier * q = to_quantifier(child);
                     expr * body = q->get_expr();
                     result = m_manager.update_quantifier(q, !q->is_forall(), m_manager.mk_not(body));
+                    return true;
                 }
                 else {
-            result = m_manager.mk_not(child);
+                    return false;
                 }
-        return;
             }
             
             bool found_quantifier = false;
@@ -144,17 +156,25 @@ void pull_quant::pull_quant1(func_decl * d, unsigned num_children, expr * const
                                                  m_manager.mk_app(d, new_adjusted_children.size(), new_adjusted_children.c_ptr()),
                                                  w,
                                                  qid);
+                return true;
             }
             else {
                 SASSERT(!found_quantifier);
+                return false;
+            }
+        }
+
+        void pull_quant1(func_decl * d, unsigned num_children, expr * const * children, expr_ref & result) {
+            if (!pull_quant1_core(d, num_children, children, result)) {
                 result = m_manager.mk_app(d, num_children, children);
             }
-}
+        }
 
-void pull_quant::pull_quant1(quantifier * q, expr * new_expr, expr_ref & result) {
+
+        void pull_quant1_core(quantifier * q, expr * new_expr, expr_ref & result) {
             // The original formula was in SNF, so the original quantifiers must be universal.
             SASSERT(is_forall(q));
-    if (is_forall(new_expr)) { 
+            SASSERT(is_forall(new_expr));
             quantifier * nested_q = to_quantifier(new_expr);
             ptr_buffer<sort> var_sorts;
             buffer<symbol>   var_names;
@@ -171,23 +191,30 @@ void pull_quant::pull_quant1(quantifier * q, expr * new_expr, expr_ref & result)
                                          std::min(q->get_weight(), nested_q->get_weight()),
                                          q->get_qid());
         }
+
+        void pull_quant1(quantifier * q, expr * new_expr, expr_ref & result) {
+            // The original formula was in SNF, so the original quantifiers must be universal.
+            SASSERT(is_forall(q));
+            if (is_forall(new_expr)) { 
+                pull_quant1_core(q, new_expr, result);
+            }
             else {
                 SASSERT(!is_quantifier(new_expr));
                 result = m_manager.update_quantifier(q, new_expr);
             }
-}
+        }
 
-void pull_quant::pull_quant1(expr * n, expr_ref & result) {
+        void pull_quant1(expr * n, expr_ref & result) {
             if (is_app(n))
                 pull_quant1(to_app(n)->get_decl(), to_app(n)->get_num_args(), to_app(n)->get_args(), result);
             else if (is_quantifier(n))
                 pull_quant1(to_quantifier(n), to_quantifier(n)->get_expr(), result);
             else
                 result = n;
-}
+        }
         
-// Code for proof generation...
+        // Code for proof generation...
-void pull_quant::pull_quant2(expr * n, expr_ref & r, proof_ref & pr) {
+        void pull_quant2(expr * n, expr_ref & r, proof_ref & pr) {
             pr = 0;
             if (is_app(n)) {
                 expr_ref_buffer   new_args(m_manager);
@@ -227,159 +254,135 @@ void pull_quant::pull_quant2(expr * n, expr_ref & r, proof_ref & pr) {
             else {
                 r  = n;
             }
-}
+        }
 
-bool pull_quant::visit_children(expr * n) {
+        br_status reduce_app(func_decl * f, unsigned num, expr * const * args, expr_ref & result, proof_ref & result_pr) {
-    bool visited = true;
+            if (!m_manager.is_or(f) && !m_manager.is_and(f) && !m_manager.is_not(f))
-    unsigned j;
+                return BR_FAILED;
-    switch(n->get_kind()) {
-    case AST_APP:
-        // This transformation is also applied after the formula
-        // has been converted into a SNF using only OR and NOT.
-        if (m_manager.is_or(n) || m_manager.is_and(n) || m_manager.is_not(n)) {
-            j = to_app(n)->get_num_args();
-            while (j > 0) {
-                --j;
-                visit(to_app(n)->get_arg(j), visited);
-            }
-        }
-        else {
-            // This class assumes the formula is in skolem normal form.
-            SASSERT(!has_quantifiers(n));
-        }
-        break;
-    case AST_QUANTIFIER:
-        if (to_quantifier(n)->is_forall())
-            visit(to_quantifier(n)->get_expr(), visited);
-        break;
-    default:
-        break;
-    }
-    return visited;
-}
 
-void pull_quant::reduce1(expr * n) {
+            if (!pull_quant1_core(f, num, args, result))
-    switch(n->get_kind()) {
+                return BR_FAILED;
-    case AST_APP:
+
-        reduce1_app(to_app(n));
+            if (m_manager.proofs_enabled()) {
-        break;
+                result_pr = m_manager.mk_pull_quant(m_manager.mk_app(f, num, args), 
-    case AST_VAR: 
+                                                    to_quantifier(result.get()));
-        cache_result(n, n, 0); 
+            }
-        break;
+            return BR_DONE;
-    case AST_QUANTIFIER: 
+        }
-        reduce1_quantifier(to_quantifier(n));
+
-        break;
+        bool reduce_quantifier(quantifier * old_q, 
-    default:
+                               expr * new_body, 
+                               expr * const * new_patterns, 
+                               expr * const * new_no_patterns,
+                               expr_ref & result,
+                               proof_ref & result_pr) {
+
+            if (old_q->is_exists()) {
                 UNREACHABLE();
-        break;
+                return false;
             }
+
+            if (!is_forall(new_body))
+                return false;
+
+            pull_quant1_core(old_q, new_body, result);
+            if (m_manager.proofs_enabled())
+                result_pr = m_manager.mk_pull_quant(old_q, to_quantifier(result.get()));
+            return true;
+        }
+    };
+
+    struct rw : public rewriter_tpl<rw_cfg> {
+        rw_cfg m_cfg;
+        rw(ast_manager & m):
+            rewriter_tpl<rw_cfg>(m, m.proofs_enabled(), m_cfg),
+            m_cfg(m) {
+        }
+    };
+    
+    rw m_rw;
+
+    imp(ast_manager & m):
+        m_rw(m) {
+    }
+    
+    void operator()(expr * n, expr_ref & r, proof_ref & p) {
+        m_rw(n, r, p);
+    }
+};
+
+pull_quant::pull_quant(ast_manager & m) {
+    m_imp = alloc(imp, m);
 }
 
-void pull_quant::reduce1_app(app * n) {
+pull_quant::~pull_quant() {
-    if (m_manager.is_or(n) || m_manager.is_and(n) || m_manager.is_not(n)) {
+    dealloc(m_imp);
-        ptr_buffer<expr>  new_children;
-        ptr_buffer<proof> new_children_proofs;
-        unsigned num = n->get_num_args();
-        for (unsigned i = 0; i < num; i++) {
-            expr *  new_child = 0;
-            proof * new_child_pr = 0;
-            get_cached(n->get_arg(i), new_child, new_child_pr);
-            new_children.push_back(new_child);
-            if (new_child_pr) {
-                new_children_proofs.push_back(new_child_pr);
-            }
-        }
-
-        expr_ref r(m_manager);
-        pull_quant1(n->get_decl(), new_children.size(), new_children.c_ptr(), r);
-        proof * pr = 0;
-        if (m_manager.fine_grain_proofs()) {
-            app * n_prime = m_manager.mk_app(n->get_decl(), new_children.size(), new_children.c_ptr());
-            TRACE("proof_bug", tout << mk_pp(n, m_manager) << "\n";
-                  tout << mk_pp(n_prime, m_manager) << "\n";);
-            proof * p1 = n == n_prime ? 0 : m_manager.mk_congruence(n, n_prime, 
-                                                                    new_children_proofs.size(), new_children_proofs.c_ptr());
-            proof * p2 = n_prime == r ? 0 : m_manager.mk_pull_quant(n_prime, to_quantifier(r));
-            pr         = m_manager.mk_transitivity(p1, p2);
-        }
-        cache_result(n, r, pr);
-        return;
-    }
-    TRACE("proof_bug", tout << mk_pp(n, m_manager) << "\n";);
-    cache_result(n, n, 0);
-}
-
-void pull_quant::reduce1_quantifier(quantifier * q) {
-    if (q->is_forall()) {
-        expr * new_expr;
-        proof * new_expr_pr;
-        get_cached(q->get_expr(), new_expr, new_expr_pr);
-        expr_ref r(m_manager);
-        pull_quant1(q, new_expr, r);
-        proof * pr = 0;
-        if (m_manager.fine_grain_proofs()) {
-            quantifier * q_prime = m_manager.update_quantifier(q, new_expr);
-            proof * p1 = q == q_prime ? 0 : m_manager.mk_quant_intro(q, q_prime, new_expr_pr);
-            proof * p2 = q_prime == r ? 0 : m_manager.mk_pull_quant(q_prime, to_quantifier(r));
-            pr         = m_manager.mk_transitivity(p1, p2);
-        }
-        cache_result(q, r, pr);
-        return;
-    }
-    // should be unreachable, right?
-    UNREACHABLE();
-    cache_result(q, q, 0);
-}
-    
-pull_quant::pull_quant(ast_manager & m):
-    base_simplifier(m),
-    m_shift(m) {
 }
 
 void pull_quant::operator()(expr * n, expr_ref & r, proof_ref & p) {
-    flush_cache();
+    (*m_imp)(n, r, p);
-    m_todo.push_back(n);
-    while (!m_todo.empty()) {
-        expr * n = m_todo.back();
-        if (is_cached(n))
-            m_todo.pop_back();
-        else if (visit_children(n)) {
-            m_todo.pop_back();
-            reduce1(n);
-        }
-    }
-
-    expr  * result;
-    proof * result_proof;
-    get_cached(n, result, result_proof);
-    
-    r = result;
-    
-    switch (m_manager.proof_mode()) {
-    case PGM_DISABLED:
-        p = m_manager.mk_undef_proof();
-        break;
-    case PGM_COARSE:
-        if (result == n) 
-            p = m_manager.mk_reflexivity(n);
-        else
-            p = m_manager.mk_pull_quant_star(n, to_quantifier(result));
-        break;
-    case PGM_FINE:
-        SASSERT(result_proof || result == n);
-        p = result_proof ? result_proof : m_manager.mk_reflexivity(n);
-        break;
-    }
 }
 
-bool pull_nested_quant::visit_quantifier(quantifier * q) {
+void pull_quant::reset() {
-    // do not recurse.
+    m_imp->m_rw.reset();
+}
+
+void pull_quant::pull_quant2(expr * n, expr_ref & r, proof_ref & pr) {
+    m_imp->m_rw.cfg().pull_quant2(n, r, pr);
+}
+
+struct pull_nested_quant::imp {
+    
+    struct rw_cfg : public default_rewriter_cfg {
+        pull_quant m_pull;
+        expr_ref   m_r;
+        proof_ref  m_pr;
+
+        rw_cfg(ast_manager & m):m_pull(m), m_r(m), m_pr(m) {}
+        
+        bool get_subst(expr * s, expr * & t, proof * & t_pr) { 
+            if (!is_quantifier(s))
+                return false;
+            m_pull(to_quantifier(s), m_r, m_pr);
+            t    = m_r.get();
+            t_pr = m_pr.get();
             return true;
+        }
+    };
+    
+    struct rw : public rewriter_tpl<rw_cfg> {
+        rw_cfg m_cfg;
+        rw(ast_manager & m):
+            rewriter_tpl<rw_cfg>(m, m.proofs_enabled(), m_cfg),
+            m_cfg(m) {
+        }
+    };
+    
+    rw m_rw;
+
+    imp(ast_manager & m):
+        m_rw(m) {
+    }
+    
+    void operator()(expr * n, expr_ref & r, proof_ref & p) {
+        m_rw(n, r, p);
+    }
+};
+
+pull_nested_quant::pull_nested_quant(ast_manager & m) {
+    m_imp = alloc(imp, m);
 }
 
-void pull_nested_quant::reduce1_quantifier(quantifier * q) {
+pull_nested_quant::~pull_nested_quant() {
-    expr_ref r(m_manager);
+    dealloc(m_imp);
-    proof_ref pr(m_manager);
-    m_pull(q, r, pr);
-    cache_result(q, r, pr);
 }
+
+void pull_nested_quant::operator()(expr * n, expr_ref & r, proof_ref & p) {
+    (*m_imp)(n, r, p);
+}
+
+void pull_nested_quant::reset() {
+    m_imp->m_rw.reset();
+}
+
+

src/ast/normal_forms/pull_quant.h

@@ -19,8 +19,7 @@ Notes:
 #ifndef _PULL_QUANT_H_
 #define _PULL_QUANT_H_
 
-#include"simplifier.h"
+#include"ast.h"
-#include"var_subst.h"
 
 /**
    \brief Pull nested quantifiers in a formula. 
@@ -32,22 +31,14 @@ Notes:
    \remark If pull_quant(F) is a quantifier then its weight is 
    Min{weight(Q') | Q' is a quantifier nested in F}
 */
-class pull_quant : public base_simplifier {
+class pull_quant {
-protected:    
+    struct imp;
-    shift_vars m_shift;
+    imp *  m_imp;
-    bool visit_children(expr * n);
-    void reduce1(expr *);
-    void reduce1_app(app * n);
-    void reduce1_quantifier(quantifier * q);
-    
 public:
     pull_quant(ast_manager & m);
-    virtual ~pull_quant() {}
+    ~pull_quant();
     void operator()(expr * n, expr_ref & r, proof_ref & p);
-    void reset() { flush_cache(); }
+    void reset();
-    void pull_quant1(func_decl * d, unsigned num_children, expr * const * children, expr_ref & result);
-    void pull_quant1(quantifier * q, expr * new_expr, expr_ref & result);
-    void pull_quant1(expr * n, expr_ref & result);
     void pull_quant2(expr * n, expr_ref & r, proof_ref & pr);
 };
 
@@ -55,13 +46,14 @@ public:
    \brief After applying this transformation the formula will not
    contain nested quantifiers.
 */
-class pull_nested_quant : public simplifier {
+class pull_nested_quant {
-    pull_quant   m_pull;
+    struct imp;
-    virtual bool visit_quantifier(quantifier * q);
+    imp * m_imp;
-    virtual void reduce1_quantifier(quantifier * q);
 public:
-    pull_nested_quant(ast_manager & m):simplifier(m), m_pull(m) { enable_ac_support(false); }
+    pull_nested_quant(ast_manager & m);
-    virtual ~pull_nested_quant() {}
+    ~pull_nested_quant();
+    void operator()(expr * n, expr_ref & r, proof_ref & p);
+    void reset();
 };
 
 #endif /* _PULL_QUANT_H_ */