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Diffstat (limited to 'sys/arch/hppa/spmath/dfdiv.c')
| -rw-r--r-- | sys/arch/hppa/spmath/dfdiv.c | 404 |
1 files changed, 404 insertions, 0 deletions
diff --git a/sys/arch/hppa/spmath/dfdiv.c b/sys/arch/hppa/spmath/dfdiv.c new file mode 100644 index 00000000000..8f331698431 --- /dev/null +++ b/sys/arch/hppa/spmath/dfdiv.c @@ -0,0 +1,404 @@ +/* + * Copyright 1996 1995 by Open Software Foundation, Inc. + * All Rights Reserved + * + * Permission to use, copy, modify, and distribute this software and + * its documentation for any purpose and without fee is hereby granted, + * provided that the above copyright notice appears in all copies and + * that both the copyright notice and this permission notice appear in + * supporting documentation. + * + * OSF DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE + * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE. + * + * IN NO EVENT SHALL OSF BE LIABLE FOR ANY SPECIAL, INDIRECT, OR + * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM + * LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT, + * NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION + * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + * + */ +/* + * pmk1.1 + */ +/* + * (c) Copyright 1986 HEWLETT-PACKARD COMPANY + * + * To anyone who acknowledges that this file is provided "AS IS" + * without any express or implied warranty: + * permission to use, copy, modify, and distribute this file + * for any purpose is hereby granted without fee, provided that + * the above copyright notice and this notice appears in all + * copies, and that the name of Hewlett-Packard Company not be + * used in advertising or publicity pertaining to distribution + * of the software without specific, written prior permission. + * Hewlett-Packard Company makes no representations about the + * suitability of this software for any purpose. + */ +/* $Source: /cvs/OpenBSD/src/sys/arch/hppa/spmath/dfdiv.c,v $ + * $Revision: 1.1 $ $Author: mickey $ + * $State: Exp $ $Locker: $ + * $Date: 1998/06/23 20:33:52 $ + */ + +#include "../spmath/float.h" +#include "../spmath/dbl_float.h" + +/* + * Double Precision Floating-point Divide + */ + +dbl_fdiv(srcptr1,srcptr2,dstptr,status) + +dbl_floating_point *srcptr1, *srcptr2, *dstptr; +unsigned int *status; +{ + register unsigned int opnd1p1, opnd1p2, opnd2p1, opnd2p2; + register unsigned int opnd3p1, opnd3p2, resultp1, resultp2; + register int dest_exponent, count; + register boolean inexact = FALSE, guardbit = FALSE, stickybit = FALSE; + boolean is_tiny; + + Dbl_copyfromptr(srcptr1,opnd1p1,opnd1p2); + Dbl_copyfromptr(srcptr2,opnd2p1,opnd2p2); + /* + * set sign bit of result + */ + if (Dbl_sign(opnd1p1) ^ Dbl_sign(opnd2p1)) + Dbl_setnegativezerop1(resultp1); + else Dbl_setzerop1(resultp1); + /* + * check first operand for NaN's or infinity + */ + if (Dbl_isinfinity_exponent(opnd1p1)) { + if (Dbl_iszero_mantissa(opnd1p1,opnd1p2)) { + if (Dbl_isnotnan(opnd2p1,opnd2p2)) { + if (Dbl_isinfinity(opnd2p1,opnd2p2)) { + /* + * invalid since both operands + * are infinity + */ + if (Is_invalidtrap_enabled()) + return(INVALIDEXCEPTION); + Set_invalidflag(); + Dbl_makequietnan(resultp1,resultp2); + Dbl_copytoptr(resultp1,resultp2,dstptr); + return(NOEXCEPTION); + } + /* + * return infinity + */ + Dbl_setinfinity_exponentmantissa(resultp1,resultp2); + Dbl_copytoptr(resultp1,resultp2,dstptr); + return(NOEXCEPTION); + } + } + else { + /* + * is NaN; signaling or quiet? + */ + if (Dbl_isone_signaling(opnd1p1)) { + /* trap if INVALIDTRAP enabled */ + if (Is_invalidtrap_enabled()) + return(INVALIDEXCEPTION); + /* make NaN quiet */ + Set_invalidflag(); + Dbl_set_quiet(opnd1p1); + } + /* + * is second operand a signaling NaN? + */ + else if (Dbl_is_signalingnan(opnd2p1)) { + /* trap if INVALIDTRAP enabled */ + if (Is_invalidtrap_enabled()) + return(INVALIDEXCEPTION); + /* make NaN quiet */ + Set_invalidflag(); + Dbl_set_quiet(opnd2p1); + Dbl_copytoptr(opnd2p1,opnd2p2,dstptr); + return(NOEXCEPTION); + } + /* + * return quiet NaN + */ + Dbl_copytoptr(opnd1p1,opnd1p2,dstptr); + return(NOEXCEPTION); + } + } + /* + * check second operand for NaN's or infinity + */ + if (Dbl_isinfinity_exponent(opnd2p1)) { + if (Dbl_iszero_mantissa(opnd2p1,opnd2p2)) { + /* + * return zero + */ + Dbl_setzero_exponentmantissa(resultp1,resultp2); + Dbl_copytoptr(resultp1,resultp2,dstptr); + return(NOEXCEPTION); + } + /* + * is NaN; signaling or quiet? + */ + if (Dbl_isone_signaling(opnd2p1)) { + /* trap if INVALIDTRAP enabled */ + if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION); + /* make NaN quiet */ + Set_invalidflag(); + Dbl_set_quiet(opnd2p1); + } + /* + * return quiet NaN + */ + Dbl_copytoptr(opnd2p1,opnd2p2,dstptr); + return(NOEXCEPTION); + } + /* + * check for division by zero + */ + if (Dbl_iszero_exponentmantissa(opnd2p1,opnd2p2)) { + if (Dbl_iszero_exponentmantissa(opnd1p1,opnd1p2)) { + /* invalid since both operands are zero */ + if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION); + Set_invalidflag(); + Dbl_makequietnan(resultp1,resultp2); + Dbl_copytoptr(resultp1,resultp2,dstptr); + return(NOEXCEPTION); + } + if (Is_divisionbyzerotrap_enabled()) + return(DIVISIONBYZEROEXCEPTION); + Set_divisionbyzeroflag(); + Dbl_setinfinity_exponentmantissa(resultp1,resultp2); + Dbl_copytoptr(resultp1,resultp2,dstptr); + return(NOEXCEPTION); + } + /* + * Generate exponent + */ + dest_exponent = Dbl_exponent(opnd1p1) - Dbl_exponent(opnd2p1) + DBL_BIAS; + + /* + * Generate mantissa + */ + if (Dbl_isnotzero_exponent(opnd1p1)) { + /* set hidden bit */ + Dbl_clear_signexponent_set_hidden(opnd1p1); + } + else { + /* check for zero */ + if (Dbl_iszero_mantissa(opnd1p1,opnd1p2)) { + Dbl_setzero_exponentmantissa(resultp1,resultp2); + Dbl_copytoptr(resultp1,resultp2,dstptr); + return(NOEXCEPTION); + } + /* is denormalized, want to normalize */ + Dbl_clear_signexponent(opnd1p1); + Dbl_leftshiftby1(opnd1p1,opnd1p2); + Dbl_normalize(opnd1p1,opnd1p2,dest_exponent); + } + /* opnd2 needs to have hidden bit set with msb in hidden bit */ + if (Dbl_isnotzero_exponent(opnd2p1)) { + Dbl_clear_signexponent_set_hidden(opnd2p1); + } + else { + /* is denormalized; want to normalize */ + Dbl_clear_signexponent(opnd2p1); + Dbl_leftshiftby1(opnd2p1,opnd2p2); + while (Dbl_iszero_hiddenhigh7mantissa(opnd2p1)) { + dest_exponent+=8; + Dbl_leftshiftby8(opnd2p1,opnd2p2); + } + if (Dbl_iszero_hiddenhigh3mantissa(opnd2p1)) { + dest_exponent+=4; + Dbl_leftshiftby4(opnd2p1,opnd2p2); + } + while (Dbl_iszero_hidden(opnd2p1)) { + dest_exponent++; + Dbl_leftshiftby1(opnd2p1,opnd2p2); + } + } + + /* Divide the source mantissas */ + + /* + * A non-restoring divide algorithm is used. + */ + Twoword_subtract(opnd1p1,opnd1p2,opnd2p1,opnd2p2); + Dbl_setzero(opnd3p1,opnd3p2); + for (count=1; count <= DBL_P && (opnd1p1 || opnd1p2); count++) { + Dbl_leftshiftby1(opnd1p1,opnd1p2); + Dbl_leftshiftby1(opnd3p1,opnd3p2); + if (Dbl_iszero_sign(opnd1p1)) { + Dbl_setone_lowmantissap2(opnd3p2); + Twoword_subtract(opnd1p1,opnd1p2,opnd2p1,opnd2p2); + } + else { + Twoword_add(opnd1p1, opnd1p2, opnd2p1, opnd2p2); + } + } + if (count <= DBL_P) { + Dbl_leftshiftby1(opnd3p1,opnd3p2); + Dbl_setone_lowmantissap2(opnd3p2); + Dbl_leftshift(opnd3p1,opnd3p2,(DBL_P-count)); + if (Dbl_iszero_hidden(opnd3p1)) { + Dbl_leftshiftby1(opnd3p1,opnd3p2); + dest_exponent--; + } + } + else { + if (Dbl_iszero_hidden(opnd3p1)) { + /* need to get one more bit of result */ + Dbl_leftshiftby1(opnd1p1,opnd1p2); + Dbl_leftshiftby1(opnd3p1,opnd3p2); + if (Dbl_iszero_sign(opnd1p1)) { + Dbl_setone_lowmantissap2(opnd3p2); + Twoword_subtract(opnd1p1,opnd1p2,opnd2p1,opnd2p2); + } + else { + Twoword_add(opnd1p1,opnd1p2,opnd2p1,opnd2p2); + } + dest_exponent--; + } + if (Dbl_iszero_sign(opnd1p1)) guardbit = TRUE; + stickybit = Dbl_allp1(opnd1p1) || Dbl_allp2(opnd1p2); + } + inexact = guardbit | stickybit; + + /* + * round result + */ + if (inexact && (dest_exponent > 0 || Is_underflowtrap_enabled())) { + Dbl_clear_signexponent(opnd3p1); + switch (Rounding_mode()) { + case ROUNDPLUS: + if (Dbl_iszero_sign(resultp1)) + Dbl_increment(opnd3p1,opnd3p2); + break; + case ROUNDMINUS: + if (Dbl_isone_sign(resultp1)) + Dbl_increment(opnd3p1,opnd3p2); + break; + case ROUNDNEAREST: + if (guardbit && (stickybit || + Dbl_isone_lowmantissap2(opnd3p2))) { + Dbl_increment(opnd3p1,opnd3p2); + } + } + if (Dbl_isone_hidden(opnd3p1)) dest_exponent++; + } + Dbl_set_mantissa(resultp1,resultp2,opnd3p1,opnd3p2); + + /* + * Test for overflow + */ + if (dest_exponent >= DBL_INFINITY_EXPONENT) { + /* trap if OVERFLOWTRAP enabled */ + if (Is_overflowtrap_enabled()) { + /* + * Adjust bias of result + */ + Dbl_setwrapped_exponent(resultp1,dest_exponent,ovfl); + Dbl_copytoptr(resultp1,resultp2,dstptr); + if (inexact) + if (Is_inexacttrap_enabled()) + return(OVERFLOWEXCEPTION | INEXACTEXCEPTION); + else Set_inexactflag(); + return(OVERFLOWEXCEPTION); + } + Set_overflowflag(); + /* set result to infinity or largest number */ + Dbl_setoverflow(resultp1,resultp2); + inexact = TRUE; + } + /* + * Test for underflow + */ + else if (dest_exponent <= 0) { + /* trap if UNDERFLOWTRAP enabled */ + if (Is_underflowtrap_enabled()) { + /* + * Adjust bias of result + */ + Dbl_setwrapped_exponent(resultp1,dest_exponent,unfl); + Dbl_copytoptr(resultp1,resultp2,dstptr); + if (inexact) + if (Is_inexacttrap_enabled()) + return(UNDERFLOWEXCEPTION | INEXACTEXCEPTION); + else Set_inexactflag(); + return(UNDERFLOWEXCEPTION); + } + + /* Determine if should set underflow flag */ + is_tiny = TRUE; + if (dest_exponent == 0 && inexact) { + switch (Rounding_mode()) { + case ROUNDPLUS: + if (Dbl_iszero_sign(resultp1)) { + Dbl_increment(opnd3p1,opnd3p2); + if (Dbl_isone_hiddenoverflow(opnd3p1)) + is_tiny = FALSE; + Dbl_decrement(opnd3p1,opnd3p2); + } + break; + case ROUNDMINUS: + if (Dbl_isone_sign(resultp1)) { + Dbl_increment(opnd3p1,opnd3p2); + if (Dbl_isone_hiddenoverflow(opnd3p1)) + is_tiny = FALSE; + Dbl_decrement(opnd3p1,opnd3p2); + } + break; + case ROUNDNEAREST: + if (guardbit && (stickybit || + Dbl_isone_lowmantissap2(opnd3p2))) { + Dbl_increment(opnd3p1,opnd3p2); + if (Dbl_isone_hiddenoverflow(opnd3p1)) + is_tiny = FALSE; + Dbl_decrement(opnd3p1,opnd3p2); + } + break; + } + } + + /* + * denormalize result or set to signed zero + */ + stickybit = inexact; + Dbl_denormalize(opnd3p1,opnd3p2,dest_exponent,guardbit, + stickybit,inexact); + + /* return rounded number */ + if (inexact) { + switch (Rounding_mode()) { + case ROUNDPLUS: + if (Dbl_iszero_sign(resultp1)) { + Dbl_increment(opnd3p1,opnd3p2); + } + break; + case ROUNDMINUS: + if (Dbl_isone_sign(resultp1)) { + Dbl_increment(opnd3p1,opnd3p2); + } + break; + case ROUNDNEAREST: + if (guardbit && (stickybit || + Dbl_isone_lowmantissap2(opnd3p2))) { + Dbl_increment(opnd3p1,opnd3p2); + } + break; + } + if (is_tiny) Set_underflowflag(); + } + Dbl_set_exponentmantissa(resultp1,resultp2,opnd3p1,opnd3p2); + } + else Dbl_set_exponent(resultp1,dest_exponent); + Dbl_copytoptr(resultp1,resultp2,dstptr); + + /* check for inexact */ + if (inexact) { + if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION); + else Set_inexactflag(); + } + return(NOEXCEPTION); +} |