1. Arlen Cox
  2. z3

Source

z3 / src / cmd_context / simplify_cmd.cpp

/*++
Copyright (c) 2011 Microsoft Corporation

Module Name:

    simplify_cmd.cpp

Abstract:
    SMT2 front-end 'simplify' command.

Author:

    Leonardo (leonardo) 2011-04-20

Notes:

--*/
#include"cmd_context.h"
#include"th_rewriter.h"
#include"shared_occs.h"
#include"ast_smt_pp.h"
#include"for_each_expr.h"
#include"parametric_cmd.h"
#include"scoped_timer.h"
#include"scoped_ctrl_c.h"
#include"cancel_eh.h"
#include<iomanip>

class simplify_cmd : public parametric_cmd {
    expr *                   m_target;
public:
    simplify_cmd(char const * name = "simplify"):parametric_cmd(name) {}

    virtual char const * get_usage() const { return "<term> (<keyword> <value>)*"; }

    virtual char const * get_main_descr() const { 
        return "simplify the given term using builtin theory simplification rules.";
    }
    
    virtual void init_pdescrs(cmd_context & ctx, param_descrs & p) {
        th_rewriter::get_param_descrs(p);
        insert_timeout(p);
        p.insert(":print", CPK_BOOL, "(default: true)  print the simplified term.");
        p.insert(":print-proofs", CPK_BOOL, "(default: false) print a proof showing the original term is equal to the resultant one.");
        p.insert(":print-statistics", CPK_BOOL, "(default: false) print statistics.");
    }
    
    virtual ~simplify_cmd() {
    }
    
    virtual void prepare(cmd_context & ctx) { 
        parametric_cmd::prepare(ctx);
        m_target   = 0; 
    }

    virtual cmd_arg_kind next_arg_kind(cmd_context & ctx) const {
        if (m_target == 0) return CPK_EXPR;
        return parametric_cmd::next_arg_kind(ctx);
    }
    
    virtual void set_next_arg(cmd_context & ctx, expr * arg) {
        m_target = arg;
    }
    
    virtual void execute(cmd_context & ctx) {
        if (m_target == 0)
            throw cmd_exception("invalid simplify command, argument expected");
        expr_ref r(ctx.m());
        proof_ref pr(ctx.m());
        if (m_params.get_bool(":som", false))
            m_params.set_bool(":flat", true);
        th_rewriter s(ctx.m(), m_params);
        unsigned cache_sz;
        unsigned num_steps = 0;
        unsigned timeout   = m_params.get_uint(":timeout", UINT_MAX);
        bool failed = false;
        cancel_eh<th_rewriter> eh(s);
        { 
            scoped_ctrl_c ctrlc(eh);
            scoped_timer timer(timeout, &eh);
            cmd_context::scoped_watch sw(ctx);
            try {
                s(m_target, r, pr);
            }
            catch (z3_error & ex) {
                throw ex;
            }
            catch (z3_exception & ex) {
                ctx.regular_stream() << "(error \"simplifier failed: " << ex.msg() << "\")" << std::endl;
                failed = true;
                r = m_target;
            }
            cache_sz  = s.get_cache_size();
            num_steps = s.get_num_steps();
            s.cleanup();
        }
        if (m_params.get_bool(":print", true)) {
            ctx.display(ctx.regular_stream(), r);
            ctx.regular_stream() << std::endl; 
        }
        if (!failed && m_params.get_bool(":print-proofs", false)) {
            ast_smt_pp pp(ctx.m());
            pp.set_logic(ctx.get_logic().str().c_str());
            pp.display_expr_smt2(ctx.regular_stream(), pr.get());
            ctx.regular_stream() << std::endl;
        }
        if (m_params.get_bool(":print-statistics", false)) {
            shared_occs s1(ctx.m());
            if (!failed)
                s1(r);
            unsigned long long max_mem = memory::get_max_used_memory();
            unsigned long long mem = memory::get_allocation_size();
            ctx.regular_stream() << "(:time " << std::fixed << std::setprecision(2) << ctx.get_seconds() << " :num-steps " << num_steps
                                 << " :memory " << std::fixed << std::setprecision(2) << static_cast<double>(mem)/static_cast<double>(1024*1024)
                                 << " :max-memory " << std::fixed << std::setprecision(2) << static_cast<double>(max_mem)/static_cast<double>(1024*1024)
                                 << " :cache-size: " << cache_sz
                                 << " :num-nodes-before " << get_num_exprs(m_target);
            if (!failed)
                ctx.regular_stream() << " :num-shared " << s1.num_shared() << " :num-nodes " << get_num_exprs(r);
            ctx.regular_stream() << ")" << std::endl;
        }
    }
};


void install_simplify_cmd(cmd_context & ctx, char const * cmd_name) {
    ctx.insert(alloc(simplify_cmd, cmd_name));
}