First draft of elim_term_ite xform. Not working.

src/muz/transforms/CMakeLists.txt

@@ -1,3 +1,4 @@
+
 z3_add_component(transforms
   SOURCES
     dl_mk_array_blast.cpp
@@ -23,6 +24,7 @@ z3_add_component(transforms
     dl_transforms.cpp
     dl_mk_array_eq_rewrite.cpp
     dl_mk_array_instantiation.cpp
+    dl_mk_elim_term_ite.cpp
   COMPONENT_DEPENDENCIES
     dataflow
     hilbert

src/muz/transforms/dl_mk_elim_term_ite.cpp

@@ -0,0 +1,117 @@
+/*++
+Copyright (c) 2018 Arie Gurfinkel
+
+Module Name:
+
+    dl_mk_elim_term_ite.h
+
+Abstract:
+
+   Remove term-ite expressions from the rules
+
+Author:
+
+    Arie Gurfinkel (agurfinkel)
+
+Revision History:
+
+--*/
+
+#include "muz/transforms/dl_mk_elim_term_ite.h"
+#include "tactic/core/blast_term_ite_tactic.h"
+#include "ast/ast_util.h"
+#include "tactic/tactic.h"
+#include "tactic/core/elim_term_ite_tactic.h"
+
+namespace datalog {
+    mk_elim_term_ite::mk_elim_term_ite(context & ctx, unsigned priority) :
+        rule_transformer::plugin(priority, false),
+        m_ctx(ctx),
+        m(ctx.get_manager()),
+        rm(ctx.get_rule_manager()) {}
+
+    mk_elim_term_ite::~mk_elim_term_ite() {}
+
+    bool mk_elim_term_ite::elim(rule &r, rule_set &new_rules){
+        unsigned utsz = r.get_uninterpreted_tail_size();
+        unsigned tsz = r.get_tail_size();
+        expr_ref_vector new_conjs(m);
+        expr_ref tmp(m);
+
+        bool change = false;
+
+        for (unsigned i = utsz; i < tsz; ++i)
+            new_conjs.push_back(r.get_tail(i));
+        flatten_and(new_conjs);
+
+        expr_ref fml1(m), fml2(m), old_body(m), body(m), head(m);
+
+        // blast ite
+        old_body = m.mk_and(new_conjs.size(), new_conjs.c_ptr());
+        body = old_body;
+        blast_term_ite(body, 2);
+        change = old_body != body;
+        if (!change) {
+            new_rules.add_rule(&r);
+            return false;
+        }
+        new_conjs.reset();
+
+        // elim ite
+        tactic_ref elim_term_ite = mk_elim_term_ite_tactic(m);
+        goal_ref goal = alloc(class goal, m);
+        goal_ref_buffer result;
+        flatten_and(body, new_conjs);
+        for (auto *e : new_conjs) {
+            goal->assert_expr(e);
+        }
+        unsigned sz = goal->num_exprs();
+        (*elim_term_ite)(goal, result);
+        if (result.size() == 1) {
+            goal_ref new_goal = result[0];
+            if (new_goal->num_exprs() != sz) {
+                new_conjs.reset();
+                new_goal->get_formulas(new_conjs);
+            }
+        }
+
+
+        expr_ref_vector conjs(m);
+        for (unsigned i = 0; i < utsz; ++i)
+            conjs.push_back(r.get_tail(i));
+        conjs.append(new_conjs);
+
+        body = mk_and(conjs);
+        head = r.get_head();
+
+        fml2 = m.mk_implies(body, head);
+        proof_ref p(m);
+        rm.mk_rule(fml2, p, new_rules, r.name());
+
+        return true;
+    }
+
+
+
+    rule_set * mk_elim_term_ite::operator()(rule_set const & source) {
+        if (!m_ctx.elim_term_ite ()) {return nullptr;}
+
+        rule_set* rules = alloc(rule_set, m_ctx);
+        rules->inherit_predicates(source);
+        bool change = false;
+        for (auto *rule : source) {
+            if (m_ctx.canceled()) {
+                change = false;
+                break;
+            }
+            change |= elim(*rule, *rules);
+        }
+        if (!change) {
+            dealloc(rules);
+            rules = nullptr;
+        }
+        return rules;
+    }
+
+
+}

src/muz/transforms/dl_mk_elim_term_ite.h

@@ -0,0 +1,38 @@
+/*++
+Copyright (c) 2018 Arie Gurfinkel
+
+Module Name:
+
+    dl_mk_elim_term_ite.h
+
+Abstract:
+
+   Remove term-ite expressions from the rules
+
+Author:
+
+    Arie Gurfinkel (agurfinkel)
+
+Revision History:
+
+--*/
+#pragma once
+
+#include "muz/base/dl_context.h"
+#include "muz/base/dl_rule_set.h"
+#include "muz/base/dl_rule_transformer.h"
+#include "tactic/equiv_proof_converter.h"
+
+namespace datalog {
+    class mk_elim_term_ite : public rule_transformer::plugin {
+        context &m_ctx;
+        ast_manager &m;
+        rule_manager &rm;
+
+        bool elim(rule &r, rule_set &new_rules);
+    public:
+        mk_elim_term_ite(context &ctx, unsigned priority);
+        ~mk_elim_term_ite() override;
+        rule_set * operator()(const rule_set &source) override;
+    };
+}

src/muz/transforms/dl_transforms.cpp

@@ -35,6 +35,7 @@ Revision History:
 #include "muz/transforms/dl_mk_scale.h"
 #include "muz/transforms/dl_mk_array_eq_rewrite.h"
 #include "muz/transforms/dl_mk_array_instantiation.h"
+#include "muz/transforms/dl_mk_elim_term_ite.h"
 #include "muz/base/fp_params.hpp"
 
 namespace datalog {
@@ -95,6 +96,8 @@ namespace datalog {
         if (ctx.get_params().xform_magic()) {
             transf.register_plugin(alloc(datalog::mk_magic_symbolic, ctx, 36020));
         }
+
+        transf.register_plugin(alloc(datalog::mk_elim_term_ite, ctx, 34999));
         ctx.transform_rules(transf);
     }
 }