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Diffstat (limited to 'qemu/libdecnumber/dpd/decimal64.c')
| -rw-r--r-- | qemu/libdecnumber/dpd/decimal64.c | 849 |
1 files changed, 0 insertions, 849 deletions
diff --git a/qemu/libdecnumber/dpd/decimal64.c b/qemu/libdecnumber/dpd/decimal64.c deleted file mode 100644 index 481617641..000000000 --- a/qemu/libdecnumber/dpd/decimal64.c +++ /dev/null @@ -1,849 +0,0 @@ -/* Decimal 64-bit format module for the decNumber C Library. - Copyright (C) 2005, 2007 Free Software Foundation, Inc. - Contributed by IBM Corporation. Author Mike Cowlishaw. - - This file is part of GCC. - - GCC 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. - - In addition to the permissions in the GNU General Public License, - the Free Software Foundation gives you unlimited permission to link - the compiled version of this file into combinations with other - programs, and to distribute those combinations without any - restriction coming from the use of this file. (The General Public - License restrictions do apply in other respects; for example, they - cover modification of the file, and distribution when not linked - into a combine executable.) - - GCC 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 GCC; see the file COPYING. If not, write to the Free - Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA - 02110-1301, USA. */ - -/* ------------------------------------------------------------------ */ -/* Decimal 64-bit format module */ -/* ------------------------------------------------------------------ */ -/* This module comprises the routines for decimal64 format numbers. */ -/* Conversions are supplied to and from decNumber and String. */ -/* */ -/* This is used when decNumber provides operations, either for all */ -/* operations or as a proxy between decNumber and decSingle. */ -/* */ -/* Error handling is the same as decNumber (qv.). */ -/* ------------------------------------------------------------------ */ -#include "qemu/osdep.h" - -#include "libdecnumber/dconfig.h" -#define DECNUMDIGITS 16 /* make decNumbers with space for 16 */ -#include "libdecnumber/decNumber.h" -#include "libdecnumber/decNumberLocal.h" -#include "libdecnumber/dpd/decimal64.h" - -/* Utility routines and tables [in decimal64.c]; externs for C++ */ -extern const uInt COMBEXP[32], COMBMSD[32]; -extern const uByte BIN2CHAR[4001]; - -extern void decDigitsFromDPD(decNumber *, const uInt *, Int); -extern void decDigitsToDPD(const decNumber *, uInt *, Int); - -#if DECTRACE || DECCHECK -void decimal64Show(const decimal64 *); /* for debug */ -extern void decNumberShow(const decNumber *); /* .. */ -#endif - -/* Useful macro */ -/* Clear a structure (e.g., a decNumber) */ -#define DEC_clear(d) memset(d, 0, sizeof(*d)) - -/* define and include the tables to use for conversions */ -#define DEC_BIN2CHAR 1 -#define DEC_DPD2BIN 1 -#define DEC_BIN2DPD 1 /* used for all sizes */ -#include "libdecnumber/decDPD.h" - -/* ------------------------------------------------------------------ */ -/* decimal64FromNumber -- convert decNumber to decimal64 */ -/* */ -/* ds is the target decimal64 */ -/* dn is the source number (assumed valid) */ -/* set is the context, used only for reporting errors */ -/* */ -/* The set argument is used only for status reporting and for the */ -/* rounding mode (used if the coefficient is more than DECIMAL64_Pmax */ -/* digits or an overflow is detected). If the exponent is out of the */ -/* valid range then Overflow or Underflow will be raised. */ -/* After Underflow a subnormal result is possible. */ -/* */ -/* DEC_Clamped is set if the number has to be 'folded down' to fit, */ -/* by reducing its exponent and multiplying the coefficient by a */ -/* power of ten, or if the exponent on a zero had to be clamped. */ -/* ------------------------------------------------------------------ */ -decimal64 * decimal64FromNumber(decimal64 *d64, const decNumber *dn, - decContext *set) { - uInt status=0; /* status accumulator */ - Int ae; /* adjusted exponent */ - decNumber dw; /* work */ - decContext dc; /* .. */ - uInt *pu; /* .. */ - uInt comb, exp; /* .. */ - uInt targar[2]={0, 0}; /* target 64-bit */ - #define targhi targar[1] /* name the word with the sign */ - #define targlo targar[0] /* and the other */ - - /* If the number has too many digits, or the exponent could be */ - /* out of range then reduce the number under the appropriate */ - /* constraints. This could push the number to Infinity or zero, */ - /* so this check and rounding must be done before generating the */ - /* decimal64] */ - ae=dn->exponent+dn->digits-1; /* [0 if special] */ - if (dn->digits>DECIMAL64_Pmax /* too many digits */ - || ae>DECIMAL64_Emax /* likely overflow */ - || ae<DECIMAL64_Emin) { /* likely underflow */ - decContextDefault(&dc, DEC_INIT_DECIMAL64); /* [no traps] */ - dc.round=set->round; /* use supplied rounding */ - decNumberPlus(&dw, dn, &dc); /* (round and check) */ - /* [this changes -0 to 0, so enforce the sign...] */ - dw.bits|=dn->bits&DECNEG; - status=dc.status; /* save status */ - dn=&dw; /* use the work number */ - } /* maybe out of range */ - - if (dn->bits&DECSPECIAL) { /* a special value */ - if (dn->bits&DECINF) targhi=DECIMAL_Inf<<24; - else { /* sNaN or qNaN */ - if ((*dn->lsu!=0 || dn->digits>1) /* non-zero coefficient */ - && (dn->digits<DECIMAL64_Pmax)) { /* coefficient fits */ - decDigitsToDPD(dn, targar, 0); - } - if (dn->bits&DECNAN) targhi|=DECIMAL_NaN<<24; - else targhi|=DECIMAL_sNaN<<24; - } /* a NaN */ - } /* special */ - - else { /* is finite */ - if (decNumberIsZero(dn)) { /* is a zero */ - /* set and clamp exponent */ - if (dn->exponent<-DECIMAL64_Bias) { - exp=0; /* low clamp */ - status|=DEC_Clamped; - } - else { - exp=dn->exponent+DECIMAL64_Bias; /* bias exponent */ - if (exp>DECIMAL64_Ehigh) { /* top clamp */ - exp=DECIMAL64_Ehigh; - status|=DEC_Clamped; - } - } - comb=(exp>>5) & 0x18; /* msd=0, exp top 2 bits .. */ - } - else { /* non-zero finite number */ - uInt msd; /* work */ - Int pad=0; /* coefficient pad digits */ - - /* the dn is known to fit, but it may need to be padded */ - exp=(uInt)(dn->exponent+DECIMAL64_Bias); /* bias exponent */ - if (exp>DECIMAL64_Ehigh) { /* fold-down case */ - pad=exp-DECIMAL64_Ehigh; - exp=DECIMAL64_Ehigh; /* [to maximum] */ - status|=DEC_Clamped; - } - - /* fastpath common case */ - if (DECDPUN==3 && pad==0) { - uInt dpd[6]={0,0,0,0,0,0}; - uInt i; - Int d=dn->digits; - for (i=0; d>0; i++, d-=3) dpd[i]=BIN2DPD[dn->lsu[i]]; - targlo =dpd[0]; - targlo|=dpd[1]<<10; - targlo|=dpd[2]<<20; - if (dn->digits>6) { - targlo|=dpd[3]<<30; - targhi =dpd[3]>>2; - targhi|=dpd[4]<<8; - } - msd=dpd[5]; /* [did not really need conversion] */ - } - else { /* general case */ - decDigitsToDPD(dn, targar, pad); - /* save and clear the top digit */ - msd=targhi>>18; - targhi&=0x0003ffff; - } - - /* create the combination field */ - if (msd>=8) comb=0x18 | ((exp>>7) & 0x06) | (msd & 0x01); - else comb=((exp>>5) & 0x18) | msd; - } - targhi|=comb<<26; /* add combination field .. */ - targhi|=(exp&0xff)<<18; /* .. and exponent continuation */ - } /* finite */ - - if (dn->bits&DECNEG) targhi|=0x80000000; /* add sign bit */ - - /* now write to storage; this is now always endian */ - pu=(uInt *)d64->bytes; /* overlay */ - if (DECLITEND) { - pu[0]=targar[0]; /* directly store the low int */ - pu[1]=targar[1]; /* then the high int */ - } - else { - pu[0]=targar[1]; /* directly store the high int */ - pu[1]=targar[0]; /* then the low int */ - } - - if (status!=0) decContextSetStatus(set, status); /* pass on status */ - /* decimal64Show(d64); */ - return d64; - } /* decimal64FromNumber */ - -/* ------------------------------------------------------------------ */ -/* decimal64ToNumber -- convert decimal64 to decNumber */ -/* d64 is the source decimal64 */ -/* dn is the target number, with appropriate space */ -/* No error is possible. */ -/* ------------------------------------------------------------------ */ -decNumber * decimal64ToNumber(const decimal64 *d64, decNumber *dn) { - uInt msd; /* coefficient MSD */ - uInt exp; /* exponent top two bits */ - uInt comb; /* combination field */ - const uInt *pu; /* work */ - Int need; /* .. */ - uInt sourar[2]; /* source 64-bit */ - #define sourhi sourar[1] /* name the word with the sign */ - #define sourlo sourar[0] /* and the lower word */ - - /* load source from storage; this is endian */ - pu=(const uInt *)d64->bytes; /* overlay */ - if (DECLITEND) { - sourlo=pu[0]; /* directly load the low int */ - sourhi=pu[1]; /* then the high int */ - } - else { - sourhi=pu[0]; /* directly load the high int */ - sourlo=pu[1]; /* then the low int */ - } - - comb=(sourhi>>26)&0x1f; /* combination field */ - - decNumberZero(dn); /* clean number */ - if (sourhi&0x80000000) dn->bits=DECNEG; /* set sign if negative */ - - msd=COMBMSD[comb]; /* decode the combination field */ - exp=COMBEXP[comb]; /* .. */ - - if (exp==3) { /* is a special */ - if (msd==0) { - dn->bits|=DECINF; - return dn; /* no coefficient needed */ - } - else if (sourhi&0x02000000) dn->bits|=DECSNAN; - else dn->bits|=DECNAN; - msd=0; /* no top digit */ - } - else { /* is a finite number */ - dn->exponent=(exp<<8)+((sourhi>>18)&0xff)-DECIMAL64_Bias; /* unbiased */ - } - - /* get the coefficient */ - sourhi&=0x0003ffff; /* clean coefficient continuation */ - if (msd) { /* non-zero msd */ - sourhi|=msd<<18; /* prefix to coefficient */ - need=6; /* process 6 declets */ - } - else { /* msd=0 */ - if (!sourhi) { /* top word 0 */ - if (!sourlo) return dn; /* easy: coefficient is 0 */ - need=3; /* process at least 3 declets */ - if (sourlo&0xc0000000) need++; /* process 4 declets */ - /* [could reduce some more, here] */ - } - else { /* some bits in top word, msd=0 */ - need=4; /* process at least 4 declets */ - if (sourhi&0x0003ff00) need++; /* top declet!=0, process 5 */ - } - } /*msd=0 */ - - decDigitsFromDPD(dn, sourar, need); /* process declets */ - return dn; - } /* decimal64ToNumber */ - - -/* ------------------------------------------------------------------ */ -/* to-scientific-string -- conversion to numeric string */ -/* to-engineering-string -- conversion to numeric string */ -/* */ -/* decimal64ToString(d64, string); */ -/* decimal64ToEngString(d64, string); */ -/* */ -/* d64 is the decimal64 format number to convert */ -/* string is the string where the result will be laid out */ -/* */ -/* string must be at least 24 characters */ -/* */ -/* No error is possible, and no status can be set. */ -/* ------------------------------------------------------------------ */ -char * decimal64ToEngString(const decimal64 *d64, char *string){ - decNumber dn; /* work */ - decimal64ToNumber(d64, &dn); - decNumberToEngString(&dn, string); - return string; - } /* decimal64ToEngString */ - -char * decimal64ToString(const decimal64 *d64, char *string){ - uInt msd; /* coefficient MSD */ - Int exp; /* exponent top two bits or full */ - uInt comb; /* combination field */ - char *cstart; /* coefficient start */ - char *c; /* output pointer in string */ - const uInt *pu; /* work */ - char *s, *t; /* .. (source, target) */ - Int dpd; /* .. */ - Int pre, e; /* .. */ - const uByte *u; /* .. */ - - uInt sourar[2]; /* source 64-bit */ - #define sourhi sourar[1] /* name the word with the sign */ - #define sourlo sourar[0] /* and the lower word */ - - /* load source from storage; this is endian */ - pu=(const uInt *)d64->bytes; /* overlay */ - if (DECLITEND) { - sourlo=pu[0]; /* directly load the low int */ - sourhi=pu[1]; /* then the high int */ - } - else { - sourhi=pu[0]; /* directly load the high int */ - sourlo=pu[1]; /* then the low int */ - } - - c=string; /* where result will go */ - if (((Int)sourhi)<0) *c++='-'; /* handle sign */ - - comb=(sourhi>>26)&0x1f; /* combination field */ - msd=COMBMSD[comb]; /* decode the combination field */ - exp=COMBEXP[comb]; /* .. */ - - if (exp==3) { - if (msd==0) { /* infinity */ - strcpy(c, "Inf"); - strcpy(c+3, "inity"); - return string; /* easy */ - } - if (sourhi&0x02000000) *c++='s'; /* sNaN */ - strcpy(c, "NaN"); /* complete word */ - c+=3; /* step past */ - if (sourlo==0 && (sourhi&0x0003ffff)==0) return string; /* zero payload */ - /* otherwise drop through to add integer; set correct exp */ - exp=0; msd=0; /* setup for following code */ - } - else exp=(exp<<8)+((sourhi>>18)&0xff)-DECIMAL64_Bias; - - /* convert 16 digits of significand to characters */ - cstart=c; /* save start of coefficient */ - if (msd) *c++='0'+(char)msd; /* non-zero most significant digit */ - - /* Now decode the declets. After extracting each one, it is */ - /* decoded to binary and then to a 4-char sequence by table lookup; */ - /* the 4-chars are a 1-char length (significant digits, except 000 */ - /* has length 0). This allows us to left-align the first declet */ - /* with non-zero content, then remaining ones are full 3-char */ - /* length. We use fixed-length memcpys because variable-length */ - /* causes a subroutine call in GCC. (These are length 4 for speed */ - /* and are safe because the array has an extra terminator byte.) */ - #define dpd2char u=&BIN2CHAR[DPD2BIN[dpd]*4]; \ - if (c!=cstart) {memcpy(c, u+1, 4); c+=3;} \ - else if (*u) {memcpy(c, u+4-*u, 4); c+=*u;} - - dpd=(sourhi>>8)&0x3ff; /* declet 1 */ - dpd2char; - dpd=((sourhi&0xff)<<2) | (sourlo>>30); /* declet 2 */ - dpd2char; - dpd=(sourlo>>20)&0x3ff; /* declet 3 */ - dpd2char; - dpd=(sourlo>>10)&0x3ff; /* declet 4 */ - dpd2char; - dpd=(sourlo)&0x3ff; /* declet 5 */ - dpd2char; - - if (c==cstart) *c++='0'; /* all zeros -- make 0 */ - - if (exp==0) { /* integer or NaN case -- easy */ - *c='\0'; /* terminate */ - return string; - } - - /* non-0 exponent */ - e=0; /* assume no E */ - pre=c-cstart+exp; - /* [here, pre-exp is the digits count (==1 for zero)] */ - if (exp>0 || pre<-5) { /* need exponential form */ - e=pre-1; /* calculate E value */ - pre=1; /* assume one digit before '.' */ - } /* exponential form */ - - /* modify the coefficient, adding 0s, '.', and E+nn as needed */ - s=c-1; /* source (LSD) */ - if (pre>0) { /* ddd.ddd (plain), perhaps with E */ - char *dotat=cstart+pre; - if (dotat<c) { /* if embedded dot needed... */ - t=c; /* target */ - for (; s>=dotat; s--, t--) *t=*s; /* open the gap; leave t at gap */ - *t='.'; /* insert the dot */ - c++; /* length increased by one */ - } - - /* finally add the E-part, if needed; it will never be 0, and has */ - /* a maximum length of 3 digits */ - if (e!=0) { - *c++='E'; /* starts with E */ - *c++='+'; /* assume positive */ - if (e<0) { - *(c-1)='-'; /* oops, need '-' */ - e=-e; /* uInt, please */ - } - u=&BIN2CHAR[e*4]; /* -> length byte */ - memcpy(c, u+4-*u, 4); /* copy fixed 4 characters [is safe] */ - c+=*u; /* bump pointer appropriately */ - } - *c='\0'; /* add terminator */ - /*printf("res %s\n", string); */ - return string; - } /* pre>0 */ - - /* -5<=pre<=0: here for plain 0.ddd or 0.000ddd forms (can never have E) */ - t=c+1-pre; - *(t+1)='\0'; /* can add terminator now */ - for (; s>=cstart; s--, t--) *t=*s; /* shift whole coefficient right */ - c=cstart; - *c++='0'; /* always starts with 0. */ - *c++='.'; - for (; pre<0; pre++) *c++='0'; /* add any 0's after '.' */ - /*printf("res %s\n", string); */ - return string; - } /* decimal64ToString */ - -/* ------------------------------------------------------------------ */ -/* to-number -- conversion from numeric string */ -/* */ -/* decimal64FromString(result, string, set); */ -/* */ -/* result is the decimal64 format number which gets the result of */ -/* the conversion */ -/* *string is the character string which should contain a valid */ -/* number (which may be a special value) */ -/* set is the context */ -/* */ -/* The context is supplied to this routine is used for error handling */ -/* (setting of status and traps) and for the rounding mode, only. */ -/* If an error occurs, the result will be a valid decimal64 NaN. */ -/* ------------------------------------------------------------------ */ -decimal64 * decimal64FromString(decimal64 *result, const char *string, - decContext *set) { - decContext dc; /* work */ - decNumber dn; /* .. */ - - decContextDefault(&dc, DEC_INIT_DECIMAL64); /* no traps, please */ - dc.round=set->round; /* use supplied rounding */ - - decNumberFromString(&dn, string, &dc); /* will round if needed */ - - decimal64FromNumber(result, &dn, &dc); - if (dc.status!=0) { /* something happened */ - decContextSetStatus(set, dc.status); /* .. pass it on */ - } - return result; - } /* decimal64FromString */ - -/* ------------------------------------------------------------------ */ -/* decimal64IsCanonical -- test whether encoding is canonical */ -/* d64 is the source decimal64 */ -/* returns 1 if the encoding of d64 is canonical, 0 otherwise */ -/* No error is possible. */ -/* ------------------------------------------------------------------ */ -uint32_t decimal64IsCanonical(const decimal64 *d64) { - decNumber dn; /* work */ - decimal64 canon; /* .. */ - decContext dc; /* .. */ - decContextDefault(&dc, DEC_INIT_DECIMAL64); - decimal64ToNumber(d64, &dn); - decimal64FromNumber(&canon, &dn, &dc);/* canon will now be canonical */ - return memcmp(d64, &canon, DECIMAL64_Bytes)==0; - } /* decimal64IsCanonical */ - -/* ------------------------------------------------------------------ */ -/* decimal64Canonical -- copy an encoding, ensuring it is canonical */ -/* d64 is the source decimal64 */ -/* result is the target (may be the same decimal64) */ -/* returns result */ -/* No error is possible. */ -/* ------------------------------------------------------------------ */ -decimal64 * decimal64Canonical(decimal64 *result, const decimal64 *d64) { - decNumber dn; /* work */ - decContext dc; /* .. */ - decContextDefault(&dc, DEC_INIT_DECIMAL64); - decimal64ToNumber(d64, &dn); - decimal64FromNumber(result, &dn, &dc);/* result will now be canonical */ - return result; - } /* decimal64Canonical */ - -#if DECTRACE || DECCHECK -/* Macros for accessing decimal64 fields. These assume the - argument is a reference (pointer) to the decimal64 structure, - and the decimal64 is in network byte order (big-endian) */ -/* Get sign */ -#define decimal64Sign(d) ((unsigned)(d)->bytes[0]>>7) - -/* Get combination field */ -#define decimal64Comb(d) (((d)->bytes[0] & 0x7c)>>2) - -/* Get exponent continuation [does not remove bias] */ -#define decimal64ExpCon(d) ((((d)->bytes[0] & 0x03)<<6) \ - | ((unsigned)(d)->bytes[1]>>2)) - -/* Set sign [this assumes sign previously 0] */ -#define decimal64SetSign(d, b) { \ - (d)->bytes[0]|=((unsigned)(b)<<7);} - -/* Set exponent continuation [does not apply bias] */ -/* This assumes range has been checked and exponent previously 0; */ -/* type of exponent must be unsigned */ -#define decimal64SetExpCon(d, e) { \ - (d)->bytes[0]|=(uint8_t)((e)>>6); \ - (d)->bytes[1]|=(uint8_t)(((e)&0x3F)<<2);} - -/* ------------------------------------------------------------------ */ -/* decimal64Show -- display a decimal64 in hexadecimal [debug aid] */ -/* d64 -- the number to show */ -/* ------------------------------------------------------------------ */ -/* Also shows sign/cob/expconfields extracted */ -void decimal64Show(const decimal64 *d64) { - char buf[DECIMAL64_Bytes*2+1]; - Int i, j=0; - - if (DECLITEND) { - for (i=0; i<DECIMAL64_Bytes; i++, j+=2) { - sprintf(&buf[j], "%02x", d64->bytes[7-i]); - } - printf(" D64> %s [S:%d Cb:%02x Ec:%02x] LittleEndian\n", buf, - d64->bytes[7]>>7, (d64->bytes[7]>>2)&0x1f, - ((d64->bytes[7]&0x3)<<6)| (d64->bytes[6]>>2)); - } - else { /* big-endian */ - for (i=0; i<DECIMAL64_Bytes; i++, j+=2) { - sprintf(&buf[j], "%02x", d64->bytes[i]); - } - printf(" D64> %s [S:%d Cb:%02x Ec:%02x] BigEndian\n", buf, - decimal64Sign(d64), decimal64Comb(d64), decimal64ExpCon(d64)); - } - } /* decimal64Show */ -#endif - -/* ================================================================== */ -/* Shared utility routines and tables */ -/* ================================================================== */ -/* define and include the conversion tables to use for shared code */ -#if DECDPUN==3 - #define DEC_DPD2BIN 1 -#else - #define DEC_DPD2BCD 1 -#endif -#include "libdecnumber/decDPD.h" - -/* The maximum number of decNumberUnits needed for a working copy of */ -/* the units array is the ceiling of digits/DECDPUN, where digits is */ -/* the maximum number of digits in any of the formats for which this */ -/* is used. decimal128.h must not be included in this module, so, as */ -/* a very special case, that number is defined as a literal here. */ -#define DECMAX754 34 -#define DECMAXUNITS ((DECMAX754+DECDPUN-1)/DECDPUN) - -/* ------------------------------------------------------------------ */ -/* Combination field lookup tables (uInts to save measurable work) */ -/* */ -/* COMBEXP - 2-bit most-significant-bits of exponent */ -/* [11 if an Infinity or NaN] */ -/* COMBMSD - 4-bit most-significant-digit */ -/* [0=Infinity, 1=NaN if COMBEXP=11] */ -/* */ -/* Both are indexed by the 5-bit combination field (0-31) */ -/* ------------------------------------------------------------------ */ -const uInt COMBEXP[32]={0, 0, 0, 0, 0, 0, 0, 0, - 1, 1, 1, 1, 1, 1, 1, 1, - 2, 2, 2, 2, 2, 2, 2, 2, - 0, 0, 1, 1, 2, 2, 3, 3}; -const uInt COMBMSD[32]={0, 1, 2, 3, 4, 5, 6, 7, - 0, 1, 2, 3, 4, 5, 6, 7, - 0, 1, 2, 3, 4, 5, 6, 7, - 8, 9, 8, 9, 8, 9, 0, 1}; - -/* ------------------------------------------------------------------ */ -/* decDigitsToDPD -- pack coefficient into DPD form */ -/* */ -/* dn is the source number (assumed valid, max DECMAX754 digits) */ -/* targ is 1, 2, or 4-element uInt array, which the caller must */ -/* have cleared to zeros */ -/* shift is the number of 0 digits to add on the right (normally 0) */ -/* */ -/* The coefficient must be known small enough to fit. The full */ -/* coefficient is copied, including the leading 'odd' digit. This */ -/* digit is retrieved and packed into the combination field by the */ -/* caller. */ -/* */ -/* The target uInts are altered only as necessary to receive the */ -/* digits of the decNumber. When more than one uInt is needed, they */ -/* are filled from left to right (that is, the uInt at offset 0 will */ -/* end up with the least-significant digits). */ -/* */ -/* shift is used for 'fold-down' padding. */ -/* */ -/* No error is possible. */ -/* ------------------------------------------------------------------ */ -#if DECDPUN<=4 -/* Constant multipliers for divide-by-power-of five using reciprocal */ -/* multiply, after removing powers of 2 by shifting, and final shift */ -/* of 17 [we only need up to **4] */ -static const uInt multies[]={131073, 26215, 5243, 1049, 210}; -/* QUOT10 -- macro to return the quotient of unit u divided by 10**n */ -#define QUOT10(u, n) ((((uInt)(u)>>(n))*multies[n])>>17) -#endif -void decDigitsToDPD(const decNumber *dn, uInt *targ, Int shift) { - Int cut; /* work */ - Int n; /* output bunch counter */ - Int digits=dn->digits; /* digit countdown */ - uInt dpd; /* densely packed decimal value */ - uInt bin; /* binary value 0-999 */ - uInt *uout=targ; /* -> current output uInt */ - uInt uoff=0; /* -> current output offset [from right] */ - const Unit *inu=dn->lsu; /* -> current input unit */ - Unit uar[DECMAXUNITS]; /* working copy of units, iff shifted */ - #if DECDPUN!=3 /* not fast path */ - Unit in; /* current unit */ - #endif - - if (shift!=0) { /* shift towards most significant required */ - /* shift the units array to the left by pad digits and copy */ - /* [this code is a special case of decShiftToMost, which could */ - /* be used instead if exposed and the array were copied first] */ - const Unit *source; /* .. */ - Unit *target, *first; /* .. */ - uInt next=0; /* work */ - - source=dn->lsu+D2U(digits)-1; /* where msu comes from */ - target=uar+D2U(digits)-1+D2U(shift);/* where upper part of first cut goes */ - cut=DECDPUN-MSUDIGITS(shift); /* where to slice */ - if (cut==0) { /* unit-boundary case */ - for (; source>=dn->lsu; source--, target--) *target=*source; - } - else { - first=uar+D2U(digits+shift)-1; /* where msu will end up */ - for (; source>=dn->lsu; source--, target--) { - /* split the source Unit and accumulate remainder for next */ - #if DECDPUN<=4 - uInt quot=QUOT10(*source, cut); - uInt rem=*source-quot*DECPOWERS[cut]; - next+=quot; - #else - uInt rem=*source%DECPOWERS[cut]; - next+=*source/DECPOWERS[cut]; - #endif - if (target<=first) *target=(Unit)next; /* write to target iff valid */ - next=rem*DECPOWERS[DECDPUN-cut]; /* save remainder for next Unit */ - } - } /* shift-move */ - /* propagate remainder to one below and clear the rest */ - for (; target>=uar; target--) { - *target=(Unit)next; - next=0; - } - digits+=shift; /* add count (shift) of zeros added */ - inu=uar; /* use units in working array */ - } - - /* now densely pack the coefficient into DPD declets */ - - #if DECDPUN!=3 /* not fast path */ - in=*inu; /* current unit */ - cut=0; /* at lowest digit */ - bin=0; /* [keep compiler quiet] */ - #endif - - for(n=0; digits>0; n++) { /* each output bunch */ - #if DECDPUN==3 /* fast path, 3-at-a-time */ - bin=*inu; /* 3 digits ready for convert */ - digits-=3; /* [may go negative] */ - inu++; /* may need another */ - - #else /* must collect digit-by-digit */ - Unit dig; /* current digit */ - Int j; /* digit-in-declet count */ - for (j=0; j<3; j++) { - #if DECDPUN<=4 - Unit temp=(Unit)((uInt)(in*6554)>>16); - dig=(Unit)(in-X10(temp)); - in=temp; - #else - dig=in%10; - in=in/10; - #endif - if (j==0) bin=dig; - else if (j==1) bin+=X10(dig); - else /* j==2 */ bin+=X100(dig); - digits--; - if (digits==0) break; /* [also protects *inu below] */ - cut++; - if (cut==DECDPUN) {inu++; in=*inu; cut=0;} - } - #endif - /* here there are 3 digits in bin, or have used all input digits */ - - dpd=BIN2DPD[bin]; - - /* write declet to uInt array */ - *uout|=dpd<<uoff; - uoff+=10; - if (uoff<32) continue; /* no uInt boundary cross */ - uout++; - uoff-=32; - *uout|=dpd>>(10-uoff); /* collect top bits */ - } /* n declets */ - return; - } /* decDigitsToDPD */ - -/* ------------------------------------------------------------------ */ -/* decDigitsFromDPD -- unpack a format's coefficient */ -/* */ -/* dn is the target number, with 7, 16, or 34-digit space. */ -/* sour is a 1, 2, or 4-element uInt array containing only declets */ -/* declets is the number of (right-aligned) declets in sour to */ -/* be processed. This may be 1 more than the obvious number in */ -/* a format, as any top digit is prefixed to the coefficient */ -/* continuation field. It also may be as small as 1, as the */ -/* caller may pre-process leading zero declets. */ -/* */ -/* When doing the 'extra declet' case care is taken to avoid writing */ -/* extra digits when there are leading zeros, as these could overflow */ -/* the units array when DECDPUN is not 3. */ -/* */ -/* The target uInts are used only as necessary to process declets */ -/* declets into the decNumber. When more than one uInt is needed, */ -/* they are used from left to right (that is, the uInt at offset 0 */ -/* provides the least-significant digits). */ -/* */ -/* dn->digits is set, but not the sign or exponent. */ -/* No error is possible [the redundant 888 codes are allowed]. */ -/* ------------------------------------------------------------------ */ -void decDigitsFromDPD(decNumber *dn, const uInt *sour, Int declets) { - - uInt dpd; /* collector for 10 bits */ - Int n; /* counter */ - Unit *uout=dn->lsu; /* -> current output unit */ - Unit *last=uout; /* will be unit containing msd */ - const uInt *uin=sour; /* -> current input uInt */ - uInt uoff=0; /* -> current input offset [from right] */ - - #if DECDPUN!=3 - uInt bcd; /* BCD result */ - uInt nibble; /* work */ - Unit out=0; /* accumulator */ - Int cut=0; /* power of ten in current unit */ - #endif - #if DECDPUN>4 - uInt const *pow; /* work */ - #endif - - /* Expand the densely-packed integer, right to left */ - for (n=declets-1; n>=0; n--) { /* count down declets of 10 bits */ - dpd=*uin>>uoff; - uoff+=10; - if (uoff>32) { /* crossed uInt boundary */ - uin++; - uoff-=32; - dpd|=*uin<<(10-uoff); /* get waiting bits */ - } - dpd&=0x3ff; /* clear uninteresting bits */ - - #if DECDPUN==3 - if (dpd==0) *uout=0; - else { - *uout=DPD2BIN[dpd]; /* convert 10 bits to binary 0-999 */ - last=uout; /* record most significant unit */ - } - uout++; - } /* n */ - - #else /* DECDPUN!=3 */ - if (dpd==0) { /* fastpath [e.g., leading zeros] */ - /* write out three 0 digits (nibbles); out may have digit(s) */ - cut++; - if (cut==DECDPUN) {*uout=out; if (out) {last=uout; out=0;} uout++; cut=0;} - if (n==0) break; /* [as below, works even if MSD=0] */ - cut++; - if (cut==DECDPUN) {*uout=out; if (out) {last=uout; out=0;} uout++; cut=0;} - cut++; - if (cut==DECDPUN) {*uout=out; if (out) {last=uout; out=0;} uout++; cut=0;} - continue; - } - - bcd=DPD2BCD[dpd]; /* convert 10 bits to 12 bits BCD */ - - /* now accumulate the 3 BCD nibbles into units */ - nibble=bcd & 0x00f; - if (nibble) out=(Unit)(out+nibble*DECPOWERS[cut]); - cut++; - if (cut==DECDPUN) {*uout=out; if (out) {last=uout; out=0;} uout++; cut=0;} - bcd>>=4; - - /* if this is the last declet and the remaining nibbles in bcd */ - /* are 00 then process no more nibbles, because this could be */ - /* the 'odd' MSD declet and writing any more Units would then */ - /* overflow the unit array */ - if (n==0 && !bcd) break; - - nibble=bcd & 0x00f; - if (nibble) out=(Unit)(out+nibble*DECPOWERS[cut]); - cut++; - if (cut==DECDPUN) {*uout=out; if (out) {last=uout; out=0;} uout++; cut=0;} - bcd>>=4; - - nibble=bcd & 0x00f; - if (nibble) out=(Unit)(out+nibble*DECPOWERS[cut]); - cut++; - if (cut==DECDPUN) {*uout=out; if (out) {last=uout; out=0;} uout++; cut=0;} - } /* n */ - if (cut!=0) { /* some more left over */ - *uout=out; /* write out final unit */ - if (out) last=uout; /* and note if non-zero */ - } - #endif - - /* here, last points to the most significant unit with digits; */ - /* inspect it to get the final digits count -- this is essentially */ - /* the same code as decGetDigits in decNumber.c */ - dn->digits=(last-dn->lsu)*DECDPUN+1; /* floor of digits, plus */ - /* must be at least 1 digit */ - #if DECDPUN>1 - if (*last<10) return; /* common odd digit or 0 */ - dn->digits++; /* must be 2 at least */ - #if DECDPUN>2 - if (*last<100) return; /* 10-99 */ - dn->digits++; /* must be 3 at least */ - #if DECDPUN>3 - if (*last<1000) return; /* 100-999 */ - dn->digits++; /* must be 4 at least */ - #if DECDPUN>4 - for (pow=&DECPOWERS[4]; *last>=*pow; pow++) dn->digits++; - #endif - #endif - #endif - #endif - return; - } /*decDigitsFromDPD */ |