diff --git a/src/ast/rewriter/arith_rewriter.cpp b/src/ast/rewriter/arith_rewriter.cpp index 635d5a3f2..658ca4110 100644 --- a/src/ast/rewriter/arith_rewriter.cpp +++ b/src/ast/rewriter/arith_rewriter.cpp @@ -1119,7 +1119,7 @@ br_status arith_rewriter::mk_idiv_core(expr * arg1, expr * arg2, expr_ref & resu return BR_REWRITE3; } } - if (divides(arg1, arg2, result)) { + if (get_divides(arg1, arg2, result)) { expr_ref zero(m_util.mk_int(0), m); result = m.mk_ite(m.mk_eq(zero, arg2), m_util.mk_idiv(arg1, zero), result); return BR_REWRITE_FULL; @@ -1137,7 +1137,7 @@ br_status arith_rewriter::mk_idiv_core(expr * arg1, expr * arg2, expr_ref & resu // // implement div ab ac = floor( ab / ac) = floor (b / c) = div b c // -bool arith_rewriter::divides(expr* num, expr* den, expr_ref& result) { +bool arith_rewriter::get_divides(expr* num, expr* den, expr_ref& result) { expr_fast_mark1 mark; rational num_r(1), den_r(1); expr* num_e = nullptr, *den_e = nullptr; @@ -1229,23 +1229,25 @@ static rational symmod(rational const& a, rational const& b) { if (2*r > b) r -= b; return r; } - + br_status arith_rewriter::mk_mod_core(expr * arg1, expr * arg2, expr_ref & result) { set_curr_sort(arg1->get_sort()); - numeral x, y; - bool is_num_x = m_util.is_numeral(arg1, x); - bool is_num_y = m_util.is_numeral(arg2, y); - if (is_num_x && is_num_y && !y.is_zero()) { - result = m_util.mk_int(mod(x, y)); + numeral v1, v2; + bool is_int; + bool is_num1 = m_util.is_numeral(arg1, v1, is_int); + bool is_num2 = m_util.is_numeral(arg2, v2, is_int); + + if (is_num1 && is_num2 && !v2.is_zero()) { + result = m_util.mk_numeral(mod(v1, v2), is_int); return BR_DONE; } - if (is_num_y && y.is_int() && (y.is_one() || y.is_minus_one())) { + if (is_num2 && is_int && (v2.is_one() || v2.is_minus_one())) { result = m_util.mk_numeral(numeral(0), true); return BR_DONE; } - if (arg1 == arg2 && !is_num_y) { + if (arg1 == arg2 && !is_num2) { expr_ref zero(m_util.mk_int(0), m); result = m.mk_ite(m.mk_eq(arg2, zero), m_util.mk_mod(zero, zero), zero); return BR_DONE; @@ -1253,46 +1255,45 @@ br_status arith_rewriter::mk_mod_core(expr * arg1, expr * arg2, expr_ref & resul // mod is idempotent on non-zero modulus. expr* t1, *t2; - if (m_util.is_mod(arg1, t1, t2) && t2 == arg2 && is_num_y && y.is_int() && !y.is_zero()) { - result = arg1; - return BR_DONE; - } - - rational lo, hi; - if (is_num_y && get_range(arg1, lo, hi) && 0 <= lo && hi < y) { + if (m_util.is_mod(arg1, t1, t2) && t2 == arg2 && is_num2 && is_int && !v2.is_zero()) { result = arg1; return BR_DONE; } // propagate mod inside only if there is something to reduce. - if (is_num_y && y.is_int() && y.is_pos() && (is_add(arg1) || is_mul(arg1))) { + if (is_num2 && is_int && v2.is_pos() && (is_add(arg1) || is_mul(arg1))) { TRACE("mod_bug", tout << "mk_mod:\n" << mk_ismt2_pp(arg1, m) << "\n" << mk_ismt2_pp(arg2, m) << "\n";); expr_ref_buffer args(m); bool change = false; for (expr* arg : *to_app(arg1)) { rational arg_v; - if (m_util.is_numeral(arg, arg_v) && mod(arg_v, y) != arg_v) { + if (m_util.is_numeral(arg, arg_v) && mod(arg_v, v2) != arg_v) { change = true; - args.push_back(m_util.mk_numeral(mod(arg_v, y), true)); + args.push_back(m_util.mk_numeral(mod(arg_v, v2), true)); } else if (m_util.is_mod(arg, t1, t2) && t2 == arg2) { change = true; args.push_back(t1); } - else if (m_util.is_mul(arg, t1, t2) && m_util.is_numeral(t1, arg_v) && symmod(arg_v, y) != arg_v) { + else if (m_util.is_mul(arg, t1, t2) && m_util.is_numeral(t1, arg_v) && symmod(arg_v, v2) != arg_v) { change = true; - args.push_back(m_util.mk_mul(m_util.mk_numeral(symmod(arg_v, y), true), t2)); + args.push_back(m_util.mk_mul(m_util.mk_numeral(symmod(arg_v, v2), true), t2)); } else { args.push_back(arg); } } - if (!change) { - return BR_FAILED; // did not find any target for applying simplification + if (change) { + result = m_util.mk_mod(m.mk_app(to_app(arg1)->get_decl(), args.size(), args.data()), arg2); + TRACE("mod_bug", tout << "mk_mod result: " << mk_ismt2_pp(result, m) << "\n";); + return BR_REWRITE3; } - result = m_util.mk_mod(m.mk_app(to_app(arg1)->get_decl(), args.size(), args.data()), arg2); - TRACE("mod_bug", tout << "mk_mod result: " << mk_ismt2_pp(result, m) << "\n";); - return BR_REWRITE3; + } + + expr* x, *y; + if (is_num2 && v2.is_pos() && m_util.is_mul(arg1, x, y) && m_util.is_numeral(x, v1, is_int) && divides(v1, v2)) { + result = m_util.mk_mul(x, m_util.mk_mod(y, m_util.mk_int(v2/v1))); + return BR_REWRITE1; } return BR_FAILED; diff --git a/src/ast/rewriter/arith_rewriter.h b/src/ast/rewriter/arith_rewriter.h index a9a30fe00..01fea0ac7 100644 --- a/src/ast/rewriter/arith_rewriter.h +++ b/src/ast/rewriter/arith_rewriter.h @@ -104,7 +104,7 @@ class arith_rewriter : public poly_rewriter { expr_ref neg_monomial(expr * e); expr * mk_sin_value(rational const & k); app * mk_sqrt(rational const & k); - bool divides(expr* d, expr* n, expr_ref& result); + bool get_divides(expr* d, expr* n, expr_ref& result); expr_ref remove_divisor(expr* arg, expr* num, expr* den); void flat_mul(expr* e, ptr_buffer& args); void remove_divisor(expr* d, ptr_buffer& args);