From a59907170d10385ad382b95d2bf9c713db1a3c0d Mon Sep 17 00:00:00 2001 From: "Christoph M. Wintersteiger" Date: Mon, 31 Jul 2017 18:34:46 +0100 Subject: [PATCH] Fixed renormalization in fp.mul. Relates to #872. --- src/ast/fpa/fpa2bv_converter.cpp | 8 ++++++-- src/util/mpf.cpp | 2 +- 2 files changed, 7 insertions(+), 3 deletions(-) diff --git a/src/ast/fpa/fpa2bv_converter.cpp b/src/ast/fpa/fpa2bv_converter.cpp index 0c9a1c866..864293380 100644 --- a/src/ast/fpa/fpa2bv_converter.cpp +++ b/src/ast/fpa/fpa2bv_converter.cpp @@ -1598,7 +1598,7 @@ void fpa2bv_converter::mk_fma(func_decl * f, unsigned num, expr * const * args, alignment_sticky_raw = m_bv_util.mk_extract(sbits-1, 0, shifted_big); alignment_sticky = m.mk_app(m_bv_util.get_fid(), OP_BREDOR, alignment_sticky_raw.get()); dbg_decouple("fpa2bv_fma_shifted_f_sig", shifted_f_sig); - dbg_decouple("fpa2bv_fma_f_sig_alignment_stickyw", alignment_sticky); + dbg_decouple("fpa2bv_fma_f_sig_alignment_sticky", alignment_sticky); SASSERT(is_well_sorted(m, alignment_sticky)); SASSERT(m_bv_util.get_bv_size(shifted_f_sig) == 2 * sbits); SASSERT(is_well_sorted(m, shifted_f_sig)); @@ -1677,7 +1677,8 @@ void fpa2bv_converter::mk_fma(func_decl * f, unsigned num, expr * const * args, // Renormalize expr_ref zero_e2(m), min_exp(m), sig_lz(m), max_exp_delta(m), sig_lz_capped(m), renorm_delta(m); zero_e2 = m_bv_util.mk_numeral(0, ebits + 2); - mk_min_exp(ebits+2, min_exp); + mk_min_exp(ebits, min_exp); + min_exp = m_bv_util.mk_sign_extend(2, min_exp); mk_leading_zeros(sig_abs, ebits+2, sig_lz); sig_lz = m_bv_util.mk_bv_sub(sig_lz, m_bv_util.mk_numeral(2, ebits+2)); max_exp_delta = m_bv_util.mk_bv_sub(res_exp, min_exp); @@ -1685,7 +1686,10 @@ void fpa2bv_converter::mk_fma(func_decl * f, unsigned num, expr * const * args, renorm_delta = m.mk_ite(m_bv_util.mk_sle(zero_e2, sig_lz_capped), sig_lz_capped, zero_e2); res_exp = m_bv_util.mk_bv_sub(res_exp, renorm_delta); sig_abs = m_bv_util.mk_bv_shl(sig_abs, m_bv_util.mk_zero_extend(2*sbits-ebits, renorm_delta)); + dbg_decouple("fpa2bv_fma_min_exp", min_exp); + dbg_decouple("fpa2bv_fma_max_exp_delta", max_exp_delta); dbg_decouple("fpa2bv_fma_sig_lz", sig_lz); + dbg_decouple("fpa2bv_fma_sig_lz_capped", sig_lz_capped); dbg_decouple("fpa2bv_fma_renorm_delta", renorm_delta); unsigned too_short = 0; diff --git a/src/util/mpf.cpp b/src/util/mpf.cpp index a2bf12a30..6f61a78e9 100644 --- a/src/util/mpf.cpp +++ b/src/util/mpf.cpp @@ -919,7 +919,7 @@ void mpf_manager::fma(mpf_rounding_mode rm, mpf const & x, mpf const & y, mpf co mpf_exp_t min_exp = mk_min_exp(x.ebits); unsigned sig_width = m_mpz_manager.prev_power_of_two(res.get().significand) + 1; - mpf_exp_t sig_lz = 2 * x.sbits - sig_width; // want << lz + mpf_exp_t sig_lz = 2 * x.sbits - sig_width; mpf_exp_t max_exp_delta = res.exponent() - min_exp; unsigned renorm_delta = (unsigned) std::max((mpf_exp_t)0, std::min(sig_lz, max_exp_delta)); res.get().exponent -= renorm_delta;