From 33ebdc8adc0ac55ef2e071a15bdb3236ff0d01d7 Mon Sep 17 00:00:00 2001 From: "Christoph M. Wintersteiger" Date: Thu, 27 Jul 2017 23:08:35 +0100 Subject: [PATCH] Cleaned up mpf rounder. Rewrote mpf fma. Relates to #872. --- src/ast/fpa/fpa2bv_converter.cpp | 4 - src/util/mpf.cpp | 348 ++++++++++++++++--------------- src/util/mpf.h | 3 +- 3 files changed, 184 insertions(+), 171 deletions(-) diff --git a/src/ast/fpa/fpa2bv_converter.cpp b/src/ast/fpa/fpa2bv_converter.cpp index 5b71b2c2d..0e83d7fea 100644 --- a/src/ast/fpa/fpa2bv_converter.cpp +++ b/src/ast/fpa/fpa2bv_converter.cpp @@ -3904,9 +3904,6 @@ void fpa2bv_converter::round(sort * s, expr_ref & rm, expr_ref & sgn, expr_ref & SASSERT(m_bv_util.get_bv_size(sig) == sbits+4); SASSERT(m_bv_util.get_bv_size(exp) == ebits+2); - // bool UNFen = false; - // bool OVFen = false; - expr_ref e_min(m), e_max(m); mk_min_exp(ebits, e_min); mk_max_exp(ebits, e_max); @@ -4025,7 +4022,6 @@ void fpa2bv_converter::round(sort * s, expr_ref & rm, expr_ref & sgn, expr_ref & SASSERT(is_well_sorted(m, sig)); SASSERT(m_bv_util.get_bv_size(sig) == sbits+2); - // CMW: The (OVF1 && OVFen) and (TINY && UNFen) cases are never taken. expr_ref ext_emin(m); ext_emin = m_bv_util.mk_zero_extend(2, e_min); m_simp.mk_ite(TINY, ext_emin, beta, exp); diff --git a/src/util/mpf.cpp b/src/util/mpf.cpp index fac314837..36d9e49f1 100644 --- a/src/util/mpf.cpp +++ b/src/util/mpf.cpp @@ -805,7 +805,7 @@ void mpf_manager::fma(mpf_rounding_mode rm, mpf const & x, mpf const & y, mpf co o.ebits = x.ebits; o.sbits = x.sbits; - scoped_mpf mul_res(*this, x.ebits+2, 2*x.sbits); + scoped_mpf mul_res(*this, x.ebits+2, 2*x.sbits-1); scoped_mpf a(*this, x.ebits, x.sbits), b(*this, x.ebits, x.sbits), c(*this, x.ebits, x.sbits); set(a, x); set(b, y); @@ -814,9 +814,12 @@ void mpf_manager::fma(mpf_rounding_mode rm, mpf const & x, mpf const & y, mpf co unpack(b, true); unpack(c, true); - TRACE("mpf_dbg", tout << "A = " << to_string(a) << std::endl;); - TRACE("mpf_dbg", tout << "B = " << to_string(b) << std::endl;); - TRACE("mpf_dbg", tout << "C = " << to_string(c) << std::endl;); + TRACE("mpf_dbg", tout << "A = " << to_string(a) << std::endl; + tout << "B = " << to_string(b) << std::endl; + tout << "C = " << to_string(c) << std::endl; + tout << "A = " << to_string_binary(a, 1, 0) << std::endl; + tout << "B = " << to_string_binary(b, 1, 0) << std::endl; + tout << "C = " << to_string_binary(c, 1, 0) << std::endl;); SASSERT(m_mpz_manager.lt(a.significand(), m_powers2(x.sbits))); SASSERT(m_mpz_manager.lt(b.significand(), m_powers2(x.sbits))); @@ -824,98 +827,114 @@ void mpf_manager::fma(mpf_rounding_mode rm, mpf const & x, mpf const & y, mpf co SASSERT(m_mpz_manager.ge(a.significand(), m_powers2(x.sbits-1))); SASSERT(m_mpz_manager.ge(b.significand(), m_powers2(x.sbits-1))); + // A/B in _1.[sbits-1]. mul_res.get().sign = (a.sign() != b.sign()); mul_res.get().exponent = a.exponent() + b.exponent(); - m_mpz_manager.mul(a.significand(), b.significand(), mul_res.get().significand); + m_mpz_manager.mul(a.significand(), b.significand(), mul_res.significand()); - TRACE("mpf_dbg", tout << "PRODUCT = " << to_string(mul_res) << std::endl;); + TRACE("mpf_dbg", tout << "M = " << to_string(mul_res) << std::endl; + tout << "M = " << to_string_binary(mul_res, 1, 0) << std::endl;); - // mul_res is [-1][0].[2*sbits - 2], i.e., between 2*sbits-1 and 2*sbits. + // mul_res is [-1][0].[2*sbits - 2], i.e., >= 2^(2*sbits-2) and < 2^(2*sbits). SASSERT(m_mpz_manager.lt(mul_res.significand(), m_powers2(2*x.sbits))); SASSERT(m_mpz_manager.ge(mul_res.significand(), m_powers2(2*x.sbits - 2))); - // Introduce extra bits into c. - m_mpz_manager.mul2k(c.significand(), x.sbits-1, c.significand()); + // Introduce extra bits into c in _[0].[sbits-1] s.t. c in _[0].[2*sbits-2] + c.get().ebits = x.ebits + 2; + c.get().sbits = 2 * x.sbits - 1; + m_mpz_manager.mul2k(c.significand(), x.sbits - 1); - SASSERT(m_mpz_manager.lt(c.significand(), m_powers2(2 * x.sbits - 1))); + TRACE("mpf_dbg", tout << "C_= " << to_string(c) << std::endl; + tout << "C_= " << to_string_binary(c, 1, 0) << std::endl;); + + SASSERT(m_mpz_manager.lt(c.significand(), m_powers2(2*x.sbits))); SASSERT(m_mpz_manager.is_zero(c.significand()) || - m_mpz_manager.ge(c.significand(), m_powers2(2 * x.sbits - 2))); + m_mpz_manager.ge(c.significand(), m_powers2(2*x.sbits - 2))); - TRACE("mpf_dbg", tout << "C = " << to_string(c) << std::endl;); - - if (exp(c) > exp(mul_res)) + if (exp(c) > exp(mul_res)) { + TRACE("mpf_dbg", tout << "Swap!" << std::endl;); mul_res.swap(c); + } - mpf_exp_t exp_delta = exp(mul_res) - exp(c); + mpf_exp_t exp_delta_w = exp(mul_res) - exp(c); - SASSERT(exp(mul_res) >= exp(c) && exp_delta >= 0); + SASSERT(exp(mul_res) >= exp(c) && exp_delta_w >= 0); - if (exp_delta > 2 * x.sbits) - exp_delta = 2 * x.sbits; + if (exp_delta_w > 2 * x.sbits) + exp_delta_w = 2 * x.sbits; + unsigned exp_delta = (unsigned)exp_delta_w; TRACE("mpf_dbg", tout << "exp_delta = " << exp_delta << std::endl;); // Alignment shift with sticky bit computation. scoped_mpz sticky_rem(m_mpz_manager); - m_mpz_manager.machine_div_rem(c.significand(), m_powers2((int)exp_delta), c.significand(), sticky_rem); + m_mpz_manager.machine_div_rem(c.significand(), m_powers2(exp_delta), c.significand(), sticky_rem); TRACE("mpf_dbg", tout << "alignment shift -> sig = " << m_mpz_manager.to_string(c.significand()) << " sticky_rem = " << m_mpz_manager.to_string(sticky_rem) << std::endl;); if (!m_mpz_manager.is_zero(sticky_rem) && m_mpz_manager.is_even(c.significand())) m_mpz_manager.inc(c.significand()); - TRACE("mpf_dbg", tout << "M' = " << m_mpz_manager.to_string(mul_res.significand()) << std::endl;); - TRACE("mpf_dbg", tout << "C' = " << m_mpz_manager.to_string(c.significand()) << std::endl;); + TRACE("mpf_dbg", tout << "M'= " << m_mpz_manager.to_string(mul_res.significand()) << std::endl; + tout << "M'= " << to_string_binary(mul_res, 1, 0) << std::endl; ); + TRACE("mpf_dbg", tout << "C'= " << m_mpz_manager.to_string(c.significand()) << std::endl; + tout << "C'= " << to_string_binary(c, 1, 0) << std::endl; ); + + scoped_mpf res(c); + + res.get().sign = mul_res.sign(); + res.get().exponent = mul_res.exponent(); // Significand addition + if (sgn(mul_res) != sgn(c)) { TRACE("mpf_dbg", tout << "SUBTRACTING" << std::endl;); - m_mpz_manager.sub(mul_res.significand(), c.significand(), o.significand); + m_mpz_manager.sub(mul_res.significand(), c.significand(), res.significand()); + + if (m_mpz_manager.is_neg(res.significand())) { + m_mpz_manager.abs(res.significand()); + res.get().sign |= !mul_res.sign() && c.sign(); + } } else { TRACE("mpf_dbg", tout << "ADDING" << std::endl;); - m_mpz_manager.add(mul_res.significand(), c.significand(), o.significand); + m_mpz_manager.add(mul_res.significand(), c.significand(), res.significand()); } - TRACE("mpf_dbg", tout << "sum[-1:] = " << m_mpz_manager.to_string(o.significand) << std::endl;); + TRACE("mpf_dbg", tout << "S'= " << m_mpz_manager.to_string(res.significand()) << std::endl; + tout << "S'= " << to_string_binary(res, 1, 0) << std::endl; ); - bool neg = m_mpz_manager.is_neg(o.significand); - TRACE("mpf_dbg", tout << "NEG=" << neg << std::endl;); - if (neg) m_mpz_manager.abs(o.significand); - - o.exponent = mul_res.exponent(); - - unsigned extra = 0; - // Result could overflow into 4.xxx ... - SASSERT(m_mpz_manager.lt(o.significand, m_powers2(2 * x.sbits + 2))); - if (m_mpz_manager.ge(o.significand, m_powers2(2 * x.sbits + 1))) + SASSERT(m_mpz_manager.lt(res.significand(), m_powers2(2 * x.sbits + 1))); + if (m_mpz_manager.ge(res.significand(), m_powers2(2 * x.sbits))) { - extra++; - o.exponent++; - TRACE("mpf_dbg", tout << "Addition overflew!" << std::endl;); + SASSERT(exp(res) < mk_max_exp(x.ebits)); // NYI. + + res.get().exponent++; + bool sticky = !m_mpz_manager.is_even(res.significand()); + m_mpz_manager.machine_div2k(res.significand(), 1); + if (sticky && m_mpz_manager.is_even(res.significand())) + m_mpz_manager.inc(res.significand()); + TRACE("mpf_dbg", tout << "Add/Sub overflew into 4.xxx!" << std::endl; + tout << "S*= " << to_string_binary(res, 2, 0) << std::endl;); } - // Remove the extra bits, keeping a sticky bit. - m_mpz_manager.set(sticky_rem, 0); - unsigned minbits = (4 + extra); - if (o.sbits >= minbits) - m_mpz_manager.machine_div_rem(o.significand, m_powers2(o.sbits - minbits), o.significand, sticky_rem); - else - m_mpz_manager.mul2k(o.significand, minbits - o.sbits, o.significand); + set(o, x.ebits, x.sbits, res.sign(), res.exponent(), mpz(0)); - if (!m_mpz_manager.is_zero(sticky_rem) && m_mpz_manager.is_even(o.significand)) - m_mpz_manager.inc(o.significand); + if (x.sbits >= 4) { + m_mpz_manager.set(sticky_rem, 0); + m_mpz_manager.machine_div_rem(res.significand(), m_powers2(x.sbits - 4), o.significand, sticky_rem); + if (!m_mpz_manager.is_zero(sticky_rem) && m_mpz_manager.is_even(o.significand)) + m_mpz_manager.inc(o.significand); + } + else { + m_mpz_manager.mul2k(res.significand(), 4 - x.sbits, o.significand); + } - TRACE("mpf_dbg", tout << "sum[-1:sbits+2] = " << m_mpz_manager.to_string(o.significand) << std::endl;); + TRACE("mpf_dbg", tout << "sum[-1:sbits+2] = " << m_mpz_manager.to_string(o.significand) << std::endl; + tout << "R = " << to_string_binary(o, 2, 3) << std::endl;); if (m_mpz_manager.is_zero(o.significand)) mk_zero(x.ebits, x.sbits, rm == MPF_ROUND_TOWARD_NEGATIVE, o); - else { - o.sign = ((!mul_res.sign() && c.sign() && neg) || - ( mul_res.sign() && !c.sign() && !neg) || - ( mul_res.sign() && c.sign())); - TRACE("mpf_dbg", tout << "before round = " << to_string(o) << std::endl << - "fs[-1:sbits+2] = " << m_mpz_manager.to_string(o.significand) << std::endl;); + else round(rm, o); - } } } @@ -1596,6 +1615,64 @@ std::string mpf_manager::to_string_hexfloat(mpf const & x) { return ss.str(); } +std::string mpf_manager::to_string_binary(mpf const & x, unsigned upper_extra, unsigned lower_extra) { + std::string res; + + if (is_nan(x)) + res = std::string("") + "#b0 " + + "#b" + std::string(x.ebits, '1') + " " + + "#b" + std::string(x.sbits-2, '0') + "1 " + + "(NaN)"; + else if (is_inf(x)) + res = std::string("") + "#b" + (sgn(x)?"1":"0") + " " + + "#b" + std::string(x.ebits, '1') + " " + + "#b" + std::string(x.sbits - 1, '0') + "1 " + + "(" + (sgn(x)?"-":"+") + "oo)"; + else if (is_zero(x)) + res = std::string("") + "#b" + (sgn(x) ? "1" : "0") + " " + + "#b" + std::string(x.ebits, '0') + " " + + "#b" + std::string(x.sbits - 1, '0') + " " + + "(" + (sgn(x) ? "-" : "+") + "zero)"; + else { + res = std::string("") + "#b" + (sgn(x) ? "1" : "0") + " "; + + scoped_mpz tmp(m_mpz_manager); + + if (is_denormal(x)) + m_mpz_manager.set(tmp, bias_exp(x.ebits, mk_min_exp(x.ebits))); + else { + m_mpz_manager.set(tmp, bias_exp(x.ebits, exp(x))); + } + + std::string tmp_str = ""; + for (unsigned i = 0; i < x.ebits; i++) { + tmp_str += m_mpz_manager.is_odd(tmp) ? "1" : "0"; + tmp /= 2; + } + std::reverse(tmp_str.begin(), tmp_str.end()); + res += "#b" + tmp_str + " "; + + tmp_str = ""; + m_mpz_manager.set(tmp, sig(x)); + unsigned num_bits = upper_extra + x.sbits + lower_extra; + for (unsigned i = 0; i < num_bits || !tmp.is_zero(); i++) { + tmp_str += m_mpz_manager.is_odd(tmp) ? "1" : "0"; + tmp /= 2; + if (i == lower_extra - 1) + tmp_str += ","; + if (i == x.sbits + lower_extra - 2) { + tmp_str += "."; + if (i == num_bits - 1) + tmp_str += " "; + } + } + std::reverse(tmp_str.begin(), tmp_str.end()); + res += "#b" + tmp_str; + } + + return res; +} + void mpf_manager::to_rational(mpf const & x, unsynch_mpq_manager & qm, mpq & o) { scoped_mpf a(*this); scoped_mpz n(m_mpq_manager), d(m_mpq_manager); @@ -1865,129 +1942,76 @@ void mpf_manager::mk_round_inf(mpf_rounding_mode rm, mpf & o) { } void mpf_manager::round(mpf_rounding_mode rm, mpf & o) { - // Assumptions: o.significand is of the form f[-1:0] . f[1:sbits-1] [guard,round,sticky], + // Assumptions: o.significand is of the form f[-1:0] . f[1:sbits-1] [round,extra,sticky], // i.e., it has 2 + (sbits-1) + 3 = sbits + 4 bits. - TRACE("mpf_dbg", tout << "RND: " << to_string(o) << std::endl;); + TRACE("mpf_dbg", tout << "RND: " << to_string(o) << std::endl; + tout << to_string_binary(o, 1, 3) << std::endl;); DEBUG_CODE({ - const mpz & p_m3 = m_powers2(o.sbits+5); + const mpz & p_m3 = m_powers2(o.sbits+4); SASSERT(m_mpz_manager.lt(o.significand, p_m3)); }); - // Structure of the rounder: - // (s, e_out, f_out) == (s, exprd(s, post(e, sigrd(s, f)))). + mpf_exp_t e_max = mk_max_exp(o.ebits); + mpf_exp_t e_min = mk_min_exp(o.ebits); - bool UNFen = false; // Are these supposed to be persistent flags accross calls? - bool OVFen = false; + unsigned sig_width = m_mpz_manager.prev_power_of_two(o.significand) + 1; + mpf_exp_t lz = o.sbits + 4 - sig_width; + mpf_exp_t beta = o.exponent - lz + 1; - mpf_exp_t e_max_norm = mk_max_exp(o.ebits); - mpf_exp_t e_min_norm = mk_min_exp(o.ebits); - scoped_mpz temporary(m_mpq_manager); + scoped_mpz sigma(m_mpz_manager); - TRACE("mpf_dbg", tout << "e_min_norm = " << e_min_norm << std::endl << - "e_max_norm = " << e_max_norm << std::endl;); - - const mpz & p_m1 = m_powers2(o.sbits+2); - const mpz & p_m2 = m_powers2(o.sbits+3); - (void)p_m1; - - TRACE("mpf_dbg", tout << "p_m1 = " << m_mpz_manager.to_string(p_m1) << std::endl << - "p_m2 = " << m_mpz_manager.to_string(p_m2) << std::endl;); - - bool OVF1 = o.exponent > e_max_norm || // Exponent OVF - (o.exponent == e_max_norm && m_mpz_manager.ge(o.significand, p_m2)); - - TRACE("mpf_dbg", tout << "OVF1 = " << OVF1 << std::endl;); - - int lz = 0; - scoped_mpz t(m_mpq_manager); - m_mpz_manager.set(t, p_m2); - while (m_mpz_manager.gt(t, o.significand)) { - m_mpz_manager.machine_div2k(t, 1); - lz++; + if (beta < e_min) { + // denormal significand/TINY + m_mpz_manager.set(sigma, o.exponent - e_min); + o.exponent = e_min; + } + else { + m_mpz_manager.set(sigma, lz - 1); + o.exponent = beta; } - TRACE("mpf_dbg", tout << "LZ = " << lz << std::endl;); + scoped_mpz sigma_cap(m_mpz_manager); + sigma_cap = o.sbits + 2; + m_mpz_manager.neg(sigma_cap); + if (m_mpz_manager.lt(sigma, sigma_cap)) + m_mpz_manager.set(sigma, sigma_cap); - m_mpz_manager.set(t, o.exponent); - m_mpz_manager.inc(t); - m_mpz_manager.sub(t, lz, t); - m_mpz_manager.set(temporary, e_min_norm); - m_mpz_manager.sub(t, temporary, t); - bool TINY = m_mpz_manager.is_neg(t); - - TRACE("mpf_dbg", tout << "TINY = " << TINY << std::endl;); - - mpf_exp_t alpha = 3 << (o.ebits-2); - mpf_exp_t beta = o.exponent - lz + 1; - - TRACE("mpf_dbg", tout << "alpha = " << alpha << std::endl << - "beta = " << beta << std::endl; ); - - scoped_mpz sigma(m_mpq_manager); - sigma = 0; - - if (TINY && !UNFen) { - m_mpz_manager.set(sigma, o.exponent); - m_mpz_manager.sub(sigma, temporary, sigma); - m_mpz_manager.inc(sigma); - } - else - m_mpz_manager.set(sigma, lz); - - scoped_mpz limit(m_mpq_manager); - limit = o.sbits + 2; - m_mpz_manager.neg(limit); - if (m_mpz_manager.lt(sigma, limit)) { - m_mpz_manager.set(sigma, limit); - } + TRACE("mpf_dbg", tout << "e_min_norm = " << e_min << std::endl; + tout << "e_max_norm = " << e_max << std::endl; + tout << "beta = " << beta << ", (beta < e_min) = " << (beta < e_min) << std::endl; + tout << "LZ = " << lz << std::endl; + tout << "sigma = " << m_mpz_manager.to_string(sigma) << std::endl; + tout << "sigma_cap = " << m_mpz_manager.to_string(sigma_cap) << std::endl;); // Normalization shift TRACE("mpf_dbg", tout << "Shift distance: " << m_mpz_manager.to_string(sigma) << " " << ((m_mpz_manager.is_nonneg(sigma))?"(LEFT)":"(RIGHT)") << std::endl;); - if (m_mpz_manager.le(sigma, 0)) { // Right shift + if (m_mpz_manager.le(sigma, -1)) { + // Right shift scoped_mpz sticky_rem(m_mpz_manager); - unsigned sigma_uint = (unsigned)-m_mpz_manager.get_int64(sigma); // sigma is capped, this is safe. - sigma_uint += 2; - m_mpz_manager.machine_div_rem(o.significand, m_powers2(sigma_uint), o.significand, sticky_rem); + unsigned nsigma_uint = (unsigned)-m_mpz_manager.get_int64(sigma); // sigma is capped, this is safe. + m_mpz_manager.machine_div_rem(o.significand, m_powers2(nsigma_uint), o.significand, sticky_rem); bool sticky = !m_mpz_manager.is_zero(sticky_rem); if (sticky && m_mpz_manager.is_even(o.significand)) m_mpz_manager.inc(o.significand); } - else { // Left shift + else { + // Left shift unsigned sigma_uint = static_cast(m_mpz_manager.get_int64(sigma)); - m_mpz_manager.mul2k(o.significand, sigma_uint - 1, o.significand); - bool sticky = !m_mpz_manager.is_even(o.significand); - m_mpz_manager.machine_div2k(o.significand, 1); - if (sticky && m_mpz_manager.is_even(o.significand)) - m_mpz_manager.inc(o.significand); + m_mpz_manager.mul2k(o.significand, sigma_uint, o.significand); } - TRACE("mpf_dbg", tout << "After sticky: " << to_string(o) << std::endl;); - - if (OVF1 && OVFen) { - o.exponent = beta; - o.exponent -= alpha; - } - else if (TINY && UNFen) { - o.exponent = beta; - o.exponent += alpha; - } - else if (TINY && !UNFen) - o.exponent = e_min_norm; - else - o.exponent = beta; - - TRACE("mpf_dbg", tout << "Shifted: " << to_string(o) << std::endl;); - - const mpz & p_sig = m_powers2(o.sbits); - SASSERT(TINY || (m_mpz_manager.ge(o.significand, p_sig))); + TRACE("mpf_dbg", tout << "Shifted: " << to_string(o) << std::endl; + tout << to_string_binary(o, 1, 3) << std::endl;); // Significand rounding (sigrd) - bool sticky = !m_mpz_manager.is_even(o.significand); // new sticky bit! + bool sticky = !m_mpz_manager.is_even(o.significand); + m_mpz_manager.machine_div2k(o.significand, 1); + sticky = sticky || !m_mpz_manager.is_even(o.significand); m_mpz_manager.machine_div2k(o.significand, 1); bool round = !m_mpz_manager.is_even(o.significand); m_mpz_manager.machine_div2k(o.significand, 1); @@ -2002,56 +2026,47 @@ void mpf_manager::round(mpf_rounding_mode rm, mpf & o) { bool inc = false; switch (rm) { case MPF_ROUND_NEAREST_TEVEN: inc = round && (last || sticky); break; - // case MPF_ROUND_NEAREST_TAWAY: inc = round; break; // CMW: Check - case MPF_ROUND_NEAREST_TAWAY: inc = round && (!last || sticky); break; // CMW: Fix ok? + case MPF_ROUND_NEAREST_TAWAY: inc = round && (!last || sticky); break; case MPF_ROUND_TOWARD_POSITIVE: inc = (!o.sign && (round || sticky)); break; case MPF_ROUND_TOWARD_NEGATIVE: inc = (o.sign && (round || sticky)); break; case MPF_ROUND_TOWARD_ZERO: inc = false; break; default: UNREACHABLE(); } - if (inc) { - TRACE("mpf_dbg", tout << "Rounding increment -> significand +1" << std::endl;); + TRACE("mpf_dbg", tout << "Rounding increment -> significand +" << (int)inc << std::endl;); + if (inc) m_mpz_manager.inc(o.significand); - } - else - TRACE("mpf_dbg", tout << "Rounding increment -> significand +0" << std::endl;); TRACE("mpf_dbg", tout << "Rounded significand: " << to_string(o) << std::endl;); - bool SIGovf = false; - // Post normalization (post) + const mpz & p_sig = m_powers2(o.sbits); if (m_mpz_manager.ge(o.significand, p_sig)) { m_mpz_manager.machine_div2k(o.significand, 1); o.exponent++; } - if (o.exponent > e_max_norm) - SIGovf = true; - + bool SIGovf = o.exponent > e_max; TRACE("mpf_dbg", tout << "Post-normalized: " << to_string(o) << std::endl;); - TRACE("mpf_dbg", tout << "SIGovf = " << SIGovf << std::endl;); // Exponent rounding (exprd) - bool o_has_max_exp = (o.exponent > e_max_norm); + bool o_has_max_exp = (o.exponent > e_max); bool OVF2 = SIGovf && o_has_max_exp; TRACE("mpf_dbg", tout << "OVF2 = " << OVF2 << std::endl;); TRACE("mpf_dbg", tout << "o_has_max_exp = " << o_has_max_exp << std::endl;); - if (!OVFen && OVF2) + if (OVF2) mk_round_inf(rm, o); else { const mpz & p = m_powers2(o.sbits-1); - TRACE("mpf_dbg", tout << "P: " << m_mpz_manager.to_string(p_m1) << std::endl;); if (m_mpz_manager.ge(o.significand, p)) { TRACE("mpf_dbg", tout << "NORMAL: " << m_mpz_manager.to_string(o.significand) << std::endl;); - m_mpz_manager.sub(o.significand, p, o.significand); + m_mpz_manager.sub(o.significand, p, o.significand); // Strips the hidden bit. } else { TRACE("mpf_dbg", tout << "DENORMAL: " << m_mpz_manager.to_string(o.significand) << std::endl;); @@ -2059,7 +2074,8 @@ void mpf_manager::round(mpf_rounding_mode rm, mpf & o) { } } - TRACE("mpf_dbg", tout << "ROUNDED = " << to_string(o) << std::endl;); + TRACE("mpf_dbg", tout << "ROUNDED = " << to_string(o) << std::endl; + tout << to_string_binary(o, -1, 0) << " (hidden bit, unbiased exp)." << std::endl;); } void mpf_manager::round_sqrt(mpf_rounding_mode rm, mpf & o) { diff --git a/src/util/mpf.h b/src/util/mpf.h index 31523c3ed..72c03f447 100644 --- a/src/util/mpf.h +++ b/src/util/mpf.h @@ -285,8 +285,9 @@ protected: }; std::string to_string_raw(mpf const & a); - std::string to_string_hexfloat(mpf const & a); + std::string to_string_hexfloat(mpf const & a); std::string to_string_hexfloat(bool sgn, mpf_exp_t exp, scoped_mpz const & sig, unsigned ebits, unsigned sbits, unsigned rbits); + std::string to_string_binary(mpf const & x, unsigned upper_extra, unsigned lower_extra); public: powers2 m_powers2; };