cnv_float.h
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上传日期：2013-04-10
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文件大小：13k
- /*
- * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
- #ifdef __NO_PA_HDRS
- PA header file -- do not include this header file for non-PA builds.
- #endif
- /*
- * Some more constants
- */
- #define SGL_FX_MAX_EXP 30
- #define DBL_FX_MAX_EXP 62
- #define QUAD_FX_MAX_EXP 126
- #define Dintp1(object) (object)
- #define Dintp2(object) (object)
- #define Duintp1(object) (object)
- #define Duintp2(object) (object)
- #define Qintp0(object) (object)
- #define Qintp1(object) (object)
- #define Qintp2(object) (object)
- #define Qintp3(object) (object)
- /*
- * These macros will be used specifically by the convert instructions.
- *
- *
- * Single format macros
- */
- #define Sgl_to_dbl_exponent(src_exponent,dest)
- Deposit_dexponent(dest,src_exponent+(DBL_BIAS-SGL_BIAS))
- #define Sgl_to_dbl_mantissa(src_mantissa,destA,destB)
- Deposit_dmantissap1(destA,src_mantissa>>3);
- Dmantissap2(destB) = src_mantissa << 29
- #define Sgl_isinexact_to_fix(sgl_value,exponent)
- ((exponent < (SGL_P - 1)) ?
- (Sall(sgl_value) << (SGL_EXP_LENGTH + 1 + exponent)) : FALSE)
- #define Int_isinexact_to_sgl(int_value) (int_value << 33 - SGL_EXP_LENGTH)
- #define Sgl_roundnearest_from_int(int_value,sgl_value)
- if (int_value & 1<<(SGL_EXP_LENGTH - 2)) /* round bit */
- if ((int_value << 34 - SGL_EXP_LENGTH) || Slow(sgl_value))
- Sall(sgl_value)++
- #define Dint_isinexact_to_sgl(dint_valueA,dint_valueB)
- ((Dintp1(dint_valueA) << 33 - SGL_EXP_LENGTH) || Dintp2(dint_valueB))
- #define Sgl_roundnearest_from_dint(dint_valueA,dint_valueB,sgl_value)
- if (Dintp1(dint_valueA) & 1<<(SGL_EXP_LENGTH - 2))
- if ((Dintp1(dint_valueA) << 34 - SGL_EXP_LENGTH) ||
- Dintp2(dint_valueB) || Slow(sgl_value)) Sall(sgl_value)++
- #define Dint_isinexact_to_dbl(dint_value)
- (Dintp2(dint_value) << 33 - DBL_EXP_LENGTH)
- #define Dbl_roundnearest_from_dint(dint_opndB,dbl_opndA,dbl_opndB)
- if (Dintp2(dint_opndB) & 1<<(DBL_EXP_LENGTH - 2))
- if ((Dintp2(dint_opndB) << 34 - DBL_EXP_LENGTH) || Dlowp2(dbl_opndB))
- if ((++Dallp2(dbl_opndB))==0) Dallp1(dbl_opndA)++
- #define Sgl_isone_roundbit(sgl_value,exponent)
- ((Sall(sgl_value) << (SGL_EXP_LENGTH + 1 + exponent)) >> 31)
- #define Sgl_isone_stickybit(sgl_value,exponent)
- (exponent < (SGL_P - 2) ?
- Sall(sgl_value) << (SGL_EXP_LENGTH + 2 + exponent) : FALSE)
- /*
- * Double format macros
- */
- #define Dbl_to_sgl_exponent(src_exponent,dest)
- dest = src_exponent + (SGL_BIAS - DBL_BIAS)
- #define Dbl_to_sgl_mantissa(srcA,srcB,dest,inexact,guard,sticky,odd)
- Shiftdouble(Dmantissap1(srcA),Dmantissap2(srcB),29,dest);
- guard = Dbit3p2(srcB);
- sticky = Dallp2(srcB)<<4;
- inexact = guard | sticky;
- odd = Dbit2p2(srcB)
- #define Dbl_to_sgl_denormalized(srcA,srcB,exp,dest,inexact,guard,sticky,odd,tiny)
- Deposit_dexponent(srcA,1);
- tiny = TRUE;
- if (exp >= -2) {
- if (exp == 0) {
- inexact = Dallp2(srcB) << 3;
- guard = inexact >> 31;
- sticky = inexact << 1;
- Shiftdouble(Dmantissap1(srcA),Dmantissap2(srcB),29,dest);
- odd = dest << 31;
- if (inexact) {
- switch(Rounding_mode()) {
- case ROUNDPLUS:
- if (Dbl_iszero_sign(srcA)) {
- dest++;
- if (Sgl_isone_hidden(dest))
- tiny = FALSE;
- dest--;
- }
- break;
- case ROUNDMINUS:
- if (Dbl_isone_sign(srcA)) {
- dest++;
- if (Sgl_isone_hidden(dest))
- tiny = FALSE;
- dest--;
- }
- break;
- case ROUNDNEAREST:
- if (guard && (sticky || odd)) {
- dest++;
- if (Sgl_isone_hidden(dest))
- tiny = FALSE;
- dest--;
- }
- break;
- }
- }
- /* shift right by one to get correct result */
- guard = odd;
- sticky = inexact;
- inexact |= guard;
- dest >>= 1;
- Deposit_dsign(srcA,0);
- Shiftdouble(Dallp1(srcA),Dallp2(srcB),30,dest);
- odd = dest << 31;
- }
- else {
- inexact = Dallp2(srcB) << (2 + exp);
- guard = inexact >> 31;
- sticky = inexact << 1;
- Deposit_dsign(srcA,0);
- if (exp == -2) dest = Dallp1(srcA);
- else Variable_shift_double(Dallp1(srcA),Dallp2(srcB),30-exp,dest);
- odd = dest << 31;
- }
- }
- else {
- Deposit_dsign(srcA,0);
- if (exp > (1 - SGL_P)) {
- dest = Dallp1(srcA) >> (- 2 - exp);
- inexact = Dallp1(srcA) << (34 + exp);
- guard = inexact >> 31;
- sticky = (inexact << 1) | Dallp2(srcB);
- inexact |= Dallp2(srcB);
- odd = dest << 31;
- }
- else {
- dest = 0;
- inexact = Dallp1(srcA) | Dallp2(srcB);
- if (exp == (1 - SGL_P)) {
- guard = Dhidden(srcA);
- sticky = Dmantissap1(srcA) | Dallp2(srcB);
- }
- else {
- guard = 0;
- sticky = inexact;
- }
- odd = 0;
- }
- }
- exp = 0
- #define Dbl_isinexact_to_fix(dbl_valueA,dbl_valueB,exponent)
- (exponent < (DBL_P-33) ?
- Dallp2(dbl_valueB) || Dallp1(dbl_valueA) << (DBL_EXP_LENGTH+1+exponent) :
- (exponent < (DBL_P-1) ? Dallp2(dbl_valueB) << (exponent + (33-DBL_P)) :
- FALSE))
- #define Dbl_isoverflow_to_int(exponent,dbl_valueA,dbl_valueB)
- ((exponent > SGL_FX_MAX_EXP + 1) || Dsign(dbl_valueA)==0 ||
- Dmantissap1(dbl_valueA)!=0 || (Dallp2(dbl_valueB)>>21)!=0 )
- #define Dbl_isone_roundbit(dbl_valueA,dbl_valueB,exponent)
- ((exponent < (DBL_P - 33) ?
- Dallp1(dbl_valueA) >> ((30 - DBL_EXP_LENGTH) - exponent) :
- Dallp2(dbl_valueB) >> ((DBL_P - 2) - exponent)) & 1)
- #define Dbl_isone_stickybit(dbl_valueA,dbl_valueB,exponent)
- (exponent < (DBL_P-34) ?
- (Dallp2(dbl_valueB) || Dallp1(dbl_valueA)<<(DBL_EXP_LENGTH+2+exponent)) :
- (exponent<(DBL_P-2) ? (Dallp2(dbl_valueB) << (exponent + (34-DBL_P))) :
- FALSE))
- /* Int macros */
- #define Int_from_sgl_mantissa(sgl_value,exponent)
- Sall(sgl_value) =
- (unsigned)(Sall(sgl_value) << SGL_EXP_LENGTH)>>(31 - exponent)
- #define Int_from_dbl_mantissa(dbl_valueA,dbl_valueB,exponent)
- Shiftdouble(Dallp1(dbl_valueA),Dallp2(dbl_valueB),22,Dallp1(dbl_valueA));
- if (exponent < 31) Dallp1(dbl_valueA) >>= 30 - exponent;
- else Dallp1(dbl_valueA) <<= 1
- #define Int_negate(int_value) int_value = -int_value
- /* Dint macros */
- #define Dint_from_sgl_mantissa(sgl_value,exponent,dresultA,dresultB)
- {Sall(sgl_value) <<= SGL_EXP_LENGTH; /* left-justify */
- if (exponent <= 31) {
- Dintp1(dresultA) = 0;
- Dintp2(dresultB) = (unsigned)Sall(sgl_value) >> (31 - exponent);
- }
- else {
- Dintp1(dresultA) = Sall(sgl_value) >> (63 - exponent);
- Dintp2(dresultB) = Sall(sgl_value) << (exponent - 31);
- }}
- #define Dint_from_dbl_mantissa(dbl_valueA,dbl_valueB,exponent,destA,destB)
- {if (exponent < 32) {
- Dintp1(destA) = 0;
- if (exponent <= 20)
- Dintp2(destB) = Dallp1(dbl_valueA) >> 20-exponent;
- else Variable_shift_double(Dallp1(dbl_valueA),Dallp2(dbl_valueB),
- 52-exponent,Dintp2(destB));
- }
- else {
- if (exponent <= 52) {
- Dintp1(destA) = Dallp1(dbl_valueA) >> 52-exponent;
- if (exponent == 52) Dintp2(destB) = Dallp2(dbl_valueB);
- else Variable_shift_double(Dallp1(dbl_valueA),Dallp2(dbl_valueB),
- 52-exponent,Dintp2(destB));
- }
- else {
- Variable_shift_double(Dallp1(dbl_valueA),Dallp2(dbl_valueB),
- 84-exponent,Dintp1(destA));
- Dintp2(destB) = Dallp2(dbl_valueB) << exponent-52;
- }
- }}
- #define Dint_setzero(dresultA,dresultB)
- Dintp1(dresultA) = 0;
- Dintp2(dresultB) = 0
- #define Dint_setone_sign(dresultA,dresultB)
- Dintp1(dresultA) = ~Dintp1(dresultA);
- if ((Dintp2(dresultB) = -Dintp2(dresultB)) == 0) Dintp1(dresultA)++
- #define Dint_set_minint(dresultA,dresultB)
- Dintp1(dresultA) = (unsigned int)1<<31;
- Dintp2(dresultB) = 0
- #define Dint_isone_lowp2(dresultB) (Dintp2(dresultB) & 01)
- #define Dint_increment(dresultA,dresultB)
- if ((++Dintp2(dresultB))==0) Dintp1(dresultA)++
- #define Dint_decrement(dresultA,dresultB)
- if ((Dintp2(dresultB)--)==0) Dintp1(dresultA)--
- #define Dint_negate(dresultA,dresultB)
- Dintp1(dresultA) = ~Dintp1(dresultA);
- if ((Dintp2(dresultB) = -Dintp2(dresultB))==0) Dintp1(dresultA)++
- #define Dint_copyfromptr(src,destA,destB)
- Dintp1(destA) = src->wd0;
- Dintp2(destB) = src->wd1
- #define Dint_copytoptr(srcA,srcB,dest)
- dest->wd0 = Dintp1(srcA);
- dest->wd1 = Dintp2(srcB)
- /* other macros */
- #define Find_ms_one_bit(value, position)
- {
- int var;
- for (var=8; var >=1; var >>= 1) {
- if (value >> 32 - position)
- position -= var;
- else position += var;
- }
- if ((value >> 32 - position) == 0)
- position--;
- else position -= 2;
- }
- /*
- * Unsigned int macros
- */
- #define Duint_copyfromptr(src,destA,destB)
- Dint_copyfromptr(src,destA,destB)
- #define Duint_copytoptr(srcA,srcB,dest)
- Dint_copytoptr(srcA,srcB,dest)
- #define Suint_isinexact_to_sgl(int_value)
- (int_value << 32 - SGL_EXP_LENGTH)
- #define Sgl_roundnearest_from_suint(suint_value,sgl_value)
- if (suint_value & 1<<(SGL_EXP_LENGTH - 1)) /* round bit */
- if ((suint_value << 33 - SGL_EXP_LENGTH) || Slow(sgl_value))
- Sall(sgl_value)++
- #define Duint_isinexact_to_sgl(duint_valueA,duint_valueB)
- ((Duintp1(duint_valueA) << 32 - SGL_EXP_LENGTH) || Duintp2(duint_valueB))
- #define Sgl_roundnearest_from_duint(duint_valueA,duint_valueB,sgl_value)
- if (Duintp1(duint_valueA) & 1<<(SGL_EXP_LENGTH - 1))
- if ((Duintp1(duint_valueA) << 33 - SGL_EXP_LENGTH) ||
- Duintp2(duint_valueB) || Slow(sgl_value)) Sall(sgl_value)++
- #define Duint_isinexact_to_dbl(duint_value)
- (Duintp2(duint_value) << 32 - DBL_EXP_LENGTH)
- #define Dbl_roundnearest_from_duint(duint_opndB,dbl_opndA,dbl_opndB)
- if (Duintp2(duint_opndB) & 1<<(DBL_EXP_LENGTH - 1))
- if ((Duintp2(duint_opndB) << 33 - DBL_EXP_LENGTH) || Dlowp2(dbl_opndB))
- if ((++Dallp2(dbl_opndB))==0) Dallp1(dbl_opndA)++
- #define Suint_from_sgl_mantissa(src,exponent,result)
- Sall(result) = (unsigned)(Sall(src) << SGL_EXP_LENGTH)>>(31 - exponent)
- #define Sgl_isinexact_to_unsigned(sgl_value,exponent)
- Sgl_isinexact_to_fix(sgl_value,exponent)
- #define Duint_from_sgl_mantissa(sgl_value,exponent,dresultA,dresultB)
- {Sall(sgl_value) <<= SGL_EXP_LENGTH; /* left-justify */
- if (exponent <= 31) {
- Dintp1(dresultA) = 0;
- Dintp2(dresultB) = (unsigned)Sall(sgl_value) >> (31 - exponent);
- }
- else {
- Dintp1(dresultA) = Sall(sgl_value) >> (63 - exponent);
- Dintp2(dresultB) = Sall(sgl_value) << (exponent - 31);
- }
- Sall(sgl_value) >>= SGL_EXP_LENGTH; /* return to original */
- }
- #define Duint_setzero(dresultA,dresultB)
- Dint_setzero(dresultA,dresultB)
- #define Duint_increment(dresultA,dresultB) Dint_increment(dresultA,dresultB)
- #define Duint_isone_lowp2(dresultB) Dint_isone_lowp2(dresultB)
- #define Suint_from_dbl_mantissa(srcA,srcB,exponent,dest)
- Shiftdouble(Dallp1(srcA),Dallp2(srcB),21,dest);
- dest = (unsigned)dest >> 31 - exponent
- #define Dbl_isinexact_to_unsigned(dbl_valueA,dbl_valueB,exponent)
- Dbl_isinexact_to_fix(dbl_valueA,dbl_valueB,exponent)
- #define Duint_from_dbl_mantissa(dbl_valueA,dbl_valueB,exponent,destA,destB)
- Dint_from_dbl_mantissa(dbl_valueA,dbl_valueB,exponent,destA,destB)
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