/* * Linux/PA-RISC Project (http://www.parisc-linux.org/) * * Floating-point emulation code * Copyright (C) 2001 Hewlett-Packard (Paul Bame) <bame@debian.org> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2, or (at your option) * any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ /* * BEGIN_DESC * * File: * @(#) pa/spmath/fcnvfx.c $Revision: 1.1 $ * * Purpose: * Single Floating-point to Single Fixed-point * Single Floating-point to Double Fixed-point * Double Floating-point to Single Fixed-point * Double Floating-point to Double Fixed-point * * External Interfaces: * dbl_to_dbl_fcnvfx(srcptr,nullptr,dstptr,status) * dbl_to_sgl_fcnvfx(srcptr,nullptr,dstptr,status) * sgl_to_dbl_fcnvfx(srcptr,nullptr,dstptr,status) * sgl_to_sgl_fcnvfx(srcptr,nullptr,dstptr,status) * * Internal Interfaces: * * Theory: * <<please update with a overview of the operation of this file>> * * END_DESC */ #include "float.h" #include "sgl_float.h" #include "dbl_float.h" #include "cnv_float.h" /* * Single Floating-point to Single Fixed-point */ /*ARGSUSED*/ int sgl_to_sgl_fcnvfx( sgl_floating_point *srcptr, sgl_floating_point *nullptr, int *dstptr, sgl_floating_point *status) { register unsigned int src, temp; register int src_exponent, result; register boolean inexact = FALSE; src = *srcptr; src_exponent = Sgl_exponent(src) - SGL_BIAS; /* * Test for overflow */ if (src_exponent > SGL_FX_MAX_EXP) { /* check for MININT */ if ((src_exponent > SGL_FX_MAX_EXP + 1) || Sgl_isnotzero_mantissa(src) || Sgl_iszero_sign(src)) { if (Sgl_iszero_sign(src)) result = 0x7fffffff; else result = 0x80000000; if (Is_invalidtrap_enabled()) { return(INVALIDEXCEPTION); } Set_invalidflag(); *dstptr = result; return(NOEXCEPTION); } } /* * Generate result */ if (src_exponent >= 0) { temp = src; Sgl_clear_signexponent_set_hidden(temp); Int_from_sgl_mantissa(temp,src_exponent); if (Sgl_isone_sign(src)) result = -Sgl_all(temp); else result = Sgl_all(temp); /* check for inexact */ if (Sgl_isinexact_to_fix(src,src_exponent)) { inexact = TRUE; /* round result */ switch (Rounding_mode()) { case ROUNDPLUS: if (Sgl_iszero_sign(src)) result++; break; case ROUNDMINUS: if (Sgl_isone_sign(src)) result--; break; case ROUNDNEAREST: if (Sgl_isone_roundbit(src,src_exponent)) { if (Sgl_isone_stickybit(src,src_exponent) || (Sgl_isone_lowmantissa(temp))) if (Sgl_iszero_sign(src)) result++; else result--; } } } } else { result = 0; /* check for inexact */ if (Sgl_isnotzero_exponentmantissa(src)) { inexact = TRUE; /* round result */ switch (Rounding_mode()) { case ROUNDPLUS: if (Sgl_iszero_sign(src)) result++; break; case ROUNDMINUS: if (Sgl_isone_sign(src)) result--; break; case ROUNDNEAREST: if (src_exponent == -1) if (Sgl_isnotzero_mantissa(src)) if (Sgl_iszero_sign(src)) result++; else result--; } } } *dstptr = result; if (inexact) { if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION); else Set_inexactflag(); } return(NOEXCEPTION); } /* * Single Floating-point to Double Fixed-point */ /*ARGSUSED*/ int sgl_to_dbl_fcnvfx( sgl_floating_point *srcptr, unsigned int *nullptr, dbl_integer *dstptr, unsigned int *status) { register int src_exponent, resultp1; register unsigned int src, temp, resultp2; register boolean inexact = FALSE; src = *srcptr; src_exponent = Sgl_exponent(src) - SGL_BIAS; /* * Test for overflow */ if (src_exponent > DBL_FX_MAX_EXP) { /* check for MININT */ if ((src_exponent > DBL_FX_MAX_EXP + 1) || Sgl_isnotzero_mantissa(src) || Sgl_iszero_sign(src)) { if (Sgl_iszero_sign(src)) { resultp1 = 0x7fffffff; resultp2 = 0xffffffff; } else { resultp1 = 0x80000000; resultp2 = 0; } if (Is_invalidtrap_enabled()) { return(INVALIDEXCEPTION); } Set_invalidflag(); Dint_copytoptr(resultp1,resultp2,dstptr); return(NOEXCEPTION); } Dint_set_minint(resultp1,resultp2); Dint_copytoptr(resultp1,resultp2,dstptr); return(NOEXCEPTION); } /* * Generate result */ if (src_exponent >= 0) { temp = src; Sgl_clear_signexponent_set_hidden(temp); Dint_from_sgl_mantissa(temp,src_exponent,resultp1,resultp2); if (Sgl_isone_sign(src)) { Dint_setone_sign(resultp1,resultp2); } /* check for inexact */ if (Sgl_isinexact_to_fix(src,src_exponent)) { inexact = TRUE; /* round result */ switch (Rounding_mode()) { case ROUNDPLUS: if (Sgl_iszero_sign(src)) { Dint_increment(resultp1,resultp2); } break; case ROUNDMINUS: if (Sgl_isone_sign(src)) { Dint_decrement(resultp1,resultp2); } break; case ROUNDNEAREST: if (Sgl_isone_roundbit(src,src_exponent)) if (Sgl_isone_stickybit(src,src_exponent) || (Dint_isone_lowp2(resultp2))) if (Sgl_iszero_sign(src)) { Dint_increment(resultp1,resultp2); } else { Dint_decrement(resultp1,resultp2); } } } } else { Dint_setzero(resultp1,resultp2); /* check for inexact */ if (Sgl_isnotzero_exponentmantissa(src)) { inexact = TRUE; /* round result */ switch (Rounding_mode()) { case ROUNDPLUS: if (Sgl_iszero_sign(src)) { Dint_increment(resultp1,resultp2); } break; case ROUNDMINUS: if (Sgl_isone_sign(src)) { Dint_decrement(resultp1,resultp2); } break; case ROUNDNEAREST: if (src_exponent == -1) if (Sgl_isnotzero_mantissa(src)) if (Sgl_iszero_sign(src)) { Dint_increment(resultp1,resultp2); } else { Dint_decrement(resultp1,resultp2); } } } } Dint_copytoptr(resultp1,resultp2,dstptr); if (inexact) { if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION); else Set_inexactflag(); } return(NOEXCEPTION); } /* * Double Floating-point to Single Fixed-point */ /*ARGSUSED*/ int dbl_to_sgl_fcnvfx( dbl_floating_point *srcptr, unsigned int *nullptr, int *dstptr, unsigned int *status) { register unsigned int srcp1,srcp2, tempp1,tempp2; register int src_exponent, result; register boolean inexact = FALSE; Dbl_copyfromptr(srcptr,srcp1,srcp2); src_exponent = Dbl_exponent(srcp1) - DBL_BIAS; /* * Test for overflow */ if (src_exponent > SGL_FX_MAX_EXP) { /* check for MININT */ if (Dbl_isoverflow_to_int(src_exponent,srcp1,srcp2)) { if (Dbl_iszero_sign(srcp1)) result = 0x7fffffff; else result = 0x80000000; if (Is_invalidtrap_enabled()) { return(INVALIDEXCEPTION); } Set_invalidflag(); *dstptr = result; return(NOEXCEPTION); } } /* * Generate result */ if (src_exponent >= 0) { tempp1 = srcp1; tempp2 = srcp2; Dbl_clear_signexponent_set_hidden(tempp1); Int_from_dbl_mantissa(tempp1,tempp2,src_exponent); if (Dbl_isone_sign(srcp1) && (src_exponent <= SGL_FX_MAX_EXP)) result = -Dbl_allp1(tempp1); else result = Dbl_allp1(tempp1); /* check for inexact */ if (Dbl_isinexact_to_fix(srcp1,srcp2,src_exponent)) { inexact = TRUE; /* round result */ switch (Rounding_mode()) { case ROUNDPLUS: if (Dbl_iszero_sign(srcp1)) result++; break; case ROUNDMINUS: if (Dbl_isone_sign(srcp1)) result--; break; case ROUNDNEAREST: if (Dbl_isone_roundbit(srcp1,srcp2,src_exponent)) if (Dbl_isone_stickybit(srcp1,srcp2,src_exponent) || (Dbl_isone_lowmantissap1(tempp1))) if (Dbl_iszero_sign(srcp1)) result++; else result--; } /* check for overflow */ if ((Dbl_iszero_sign(srcp1) && result < 0) || (Dbl_isone_sign(srcp1) && result > 0)) { if (Dbl_iszero_sign(srcp1)) result = 0x7fffffff; else result = 0x80000000; if (Is_invalidtrap_enabled()) { return(INVALIDEXCEPTION); } Set_invalidflag(); *dstptr = result; return(NOEXCEPTION); } } } else { result = 0; /* check for inexact */ if (Dbl_isnotzero_exponentmantissa(srcp1,srcp2)) { inexact = TRUE; /* round result */ switch (Rounding_mode()) { case ROUNDPLUS: if (Dbl_iszero_sign(srcp1)) result++; break; case ROUNDMINUS: if (Dbl_isone_sign(srcp1)) result--; break; case ROUNDNEAREST: if (src_exponent == -1) if (Dbl_isnotzero_mantissa(srcp1,srcp2)) if (Dbl_iszero_sign(srcp1)) result++; else result--; } } } *dstptr = result; if (inexact) { if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION); else Set_inexactflag(); } return(NOEXCEPTION); } /* * Double Floating-point to Double Fixed-point */ /*ARGSUSED*/ int dbl_to_dbl_fcnvfx( dbl_floating_point *srcptr, unsigned int *nullptr, dbl_integer *dstptr, unsigned int *status) { register int src_exponent, resultp1; register unsigned int srcp1, srcp2, tempp1, tempp2, resultp2; register boolean inexact = FALSE; Dbl_copyfromptr(srcptr,srcp1,srcp2); src_exponent = Dbl_exponent(srcp1) - DBL_BIAS; /* * Test for overflow */ if (src_exponent > DBL_FX_MAX_EXP) { /* check for MININT */ if ((src_exponent > DBL_FX_MAX_EXP + 1) || Dbl_isnotzero_mantissa(srcp1,srcp2) || Dbl_iszero_sign(srcp1)) { if (Dbl_iszero_sign(srcp1)) { resultp1 = 0x7fffffff; resultp2 = 0xffffffff; } else { resultp1 = 0x80000000; resultp2 = 0; } if (Is_invalidtrap_enabled()) { return(INVALIDEXCEPTION); } Set_invalidflag(); Dint_copytoptr(resultp1,resultp2,dstptr); return(NOEXCEPTION); } } /* * Generate result */ if (src_exponent >= 0) { tempp1 = srcp1; tempp2 = srcp2; Dbl_clear_signexponent_set_hidden(tempp1); Dint_from_dbl_mantissa(tempp1,tempp2,src_exponent,resultp1, resultp2); if (Dbl_isone_sign(srcp1)) { Dint_setone_sign(resultp1,resultp2); } /* check for inexact */ if (Dbl_isinexact_to_fix(srcp1,srcp2,src_exponent)) { inexact = TRUE; /* round result */ switch (Rounding_mode()) { case ROUNDPLUS: if (Dbl_iszero_sign(srcp1)) { Dint_increment(resultp1,resultp2); } break; case ROUNDMINUS: if (Dbl_isone_sign(srcp1)) { Dint_decrement(resultp1,resultp2); } break; case ROUNDNEAREST: if (Dbl_isone_roundbit(srcp1,srcp2,src_exponent)) if (Dbl_isone_stickybit(srcp1,srcp2,src_exponent) || (Dint_isone_lowp2(resultp2))) if (Dbl_iszero_sign(srcp1)) { Dint_increment(resultp1,resultp2); } else { Dint_decrement(resultp1,resultp2); } } } } else { Dint_setzero(resultp1,resultp2); /* check for inexact */ if (Dbl_isnotzero_exponentmantissa(srcp1,srcp2)) { inexact = TRUE; /* round result */ switch (Rounding_mode()) { case ROUNDPLUS: if (Dbl_iszero_sign(srcp1)) { Dint_increment(resultp1,resultp2); } break; case ROUNDMINUS: if (Dbl_isone_sign(srcp1)) { Dint_decrement(resultp1,resultp2); } break; case ROUNDNEAREST: if (src_exponent == -1) if (Dbl_isnotzero_mantissa(srcp1,srcp2)) if (Dbl_iszero_sign(srcp1)) { Dint_increment(resultp1,resultp2); } else { Dint_decrement(resultp1,resultp2); } } } } Dint_copytoptr(resultp1,resultp2,dstptr); if (inexact) { if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION); else Set_inexactflag(); } return(NOEXCEPTION); }