--- /dev/null
+/* Common code for fixed-size types in the decNumber C Library.
+ Copyright (C) 2007, 2009 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 3, or (at your option) any later
+ version.
+
+ 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.
+
+Under Section 7 of GPL version 3, you are granted additional
+permissions described in the GCC Runtime Library Exception, version
+3.1, as published by the Free Software Foundation.
+
+You should have received a copy of the GNU General Public License and
+a copy of the GCC Runtime Library Exception along with this program;
+see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
+<http://www.gnu.org/licenses/>. */
+
+/* ------------------------------------------------------------------ */
+/* decCommon.c -- common code for all three fixed-size types */
+/* ------------------------------------------------------------------ */
+/* This module comprises code that is shared between all the formats */
+/* (decSingle, decDouble, and decQuad); it includes set and extract */
+/* of format components, widening, narrowing, and string conversions. */
+/* */
+/* Unlike decNumber, parameterization takes place at compile time */
+/* rather than at runtime. The parameters are set in the decDouble.c */
+/* (etc.) files, which then include this one to produce the compiled */
+/* code. The functions here, therefore, are code shared between */
+/* multiple formats. */
+/* ------------------------------------------------------------------ */
+/* Names here refer to decFloat rather than to decDouble, etc., and */
+/* the functions are in strict alphabetical order. */
+/* Constants, tables, and debug function(s) are included only for QUAD */
+/* (which will always be compiled if DOUBLE or SINGLE are used). */
+/* */
+/* Whenever a decContext is used, only the status may be set (using */
+/* OR) or the rounding mode read; all other fields are ignored and */
+/* untouched. */
+
+#include "decCommonSymbols.h"
+
+/* names for simpler testing and default context */
+#if DECPMAX==7
+ #define SINGLE 1
+ #define DOUBLE 0
+ #define QUAD 0
+ #define DEFCONTEXT DEC_INIT_DECIMAL32
+#elif DECPMAX==16
+ #define SINGLE 0
+ #define DOUBLE 1
+ #define QUAD 0
+ #define DEFCONTEXT DEC_INIT_DECIMAL64
+#elif DECPMAX==34
+ #define SINGLE 0
+ #define DOUBLE 0
+ #define QUAD 1
+ #define DEFCONTEXT DEC_INIT_DECIMAL128
+#else
+ #error Unexpected DECPMAX value
+#endif
+
+/* Assertions */
+
+#if DECPMAX!=7 && DECPMAX!=16 && DECPMAX!=34
+ #error Unexpected Pmax (DECPMAX) value for this module
+#endif
+
+/* Assert facts about digit characters, etc. */
+#if ('9'&0x0f)!=9
+ #error This module assumes characters are of the form 0b....nnnn
+ /* where .... are don't care 4 bits and nnnn is 0000 through 1001 */
+#endif
+#if ('9'&0xf0)==('.'&0xf0)
+ #error This module assumes '.' has a different mask than a digit
+#endif
+
+/* Assert ToString lay-out conditions */
+#if DECSTRING<DECPMAX+9
+ #error ToString needs at least 8 characters for lead-in and dot
+#endif
+#if DECPMAX+DECEMAXD+5 > DECSTRING
+ #error Exponent form can be too long for ToString to lay out safely
+#endif
+#if DECEMAXD > 4
+ #error Exponent form is too long for ToString to lay out
+ /* Note: code for up to 9 digits exists in archives [decOct] */
+#endif
+
+/* Private functions used here and possibly in decBasic.c, etc. */
+static decFloat * decFinalize(decFloat *, bcdnum *, decContext *);
+static Flag decBiStr(const char *, const char *, const char *);
+
+/* Macros and private tables; those which are not format-dependent */
+/* are only included if decQuad is being built. */
+
+/* ------------------------------------------------------------------ */
+/* Combination field lookup tables (uInts to save measurable work) */
+/* */
+/* DECCOMBEXP - 2 most-significant-bits of exponent (00, 01, or */
+/* 10), shifted left for format, or DECFLOAT_Inf/NaN */
+/* DECCOMBWEXP - The same, for the next-wider format (unless QUAD) */
+/* DECCOMBMSD - 4-bit most-significant-digit */
+/* [0 if the index is a special (Infinity or NaN)] */
+/* DECCOMBFROM - 5-bit combination field from EXP top bits and MSD */
+/* (placed in uInt so no shift is needed) */
+/* */
+/* DECCOMBEXP, DECCOMBWEXP, and DECCOMBMSD are indexed by the sign */
+/* and 5-bit combination field (0-63, the second half of the table */
+/* identical to the first half) */
+/* DECCOMBFROM is indexed by expTopTwoBits*16 + msd */
+/* */
+/* DECCOMBMSD and DECCOMBFROM are not format-dependent and so are */
+/* only included once, when QUAD is being built */
+/* ------------------------------------------------------------------ */
+static const uInt DECCOMBEXP[64]={
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 1<<DECECONL, 1<<DECECONL, 1<<DECECONL, 1<<DECECONL,
+ 1<<DECECONL, 1<<DECECONL, 1<<DECECONL, 1<<DECECONL,
+ 2<<DECECONL, 2<<DECECONL, 2<<DECECONL, 2<<DECECONL,
+ 2<<DECECONL, 2<<DECECONL, 2<<DECECONL, 2<<DECECONL,
+ 0, 0, 1<<DECECONL, 1<<DECECONL,
+ 2<<DECECONL, 2<<DECECONL, DECFLOAT_Inf, DECFLOAT_NaN,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 1<<DECECONL, 1<<DECECONL, 1<<DECECONL, 1<<DECECONL,
+ 1<<DECECONL, 1<<DECECONL, 1<<DECECONL, 1<<DECECONL,
+ 2<<DECECONL, 2<<DECECONL, 2<<DECECONL, 2<<DECECONL,
+ 2<<DECECONL, 2<<DECECONL, 2<<DECECONL, 2<<DECECONL,
+ 0, 0, 1<<DECECONL, 1<<DECECONL,
+ 2<<DECECONL, 2<<DECECONL, DECFLOAT_Inf, DECFLOAT_NaN};
+#if !QUAD
+static const uInt DECCOMBWEXP[64]={
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 1<<DECWECONL, 1<<DECWECONL, 1<<DECWECONL, 1<<DECWECONL,
+ 1<<DECWECONL, 1<<DECWECONL, 1<<DECWECONL, 1<<DECWECONL,
+ 2<<DECWECONL, 2<<DECWECONL, 2<<DECWECONL, 2<<DECWECONL,
+ 2<<DECWECONL, 2<<DECWECONL, 2<<DECWECONL, 2<<DECWECONL,
+ 0, 0, 1<<DECWECONL, 1<<DECWECONL,
+ 2<<DECWECONL, 2<<DECWECONL, DECFLOAT_Inf, DECFLOAT_NaN,
+ 0, 0, 0, 0, 0, 0, 0, 0,
+ 1<<DECWECONL, 1<<DECWECONL, 1<<DECWECONL, 1<<DECWECONL,
+ 1<<DECWECONL, 1<<DECWECONL, 1<<DECWECONL, 1<<DECWECONL,
+ 2<<DECWECONL, 2<<DECWECONL, 2<<DECWECONL, 2<<DECWECONL,
+ 2<<DECWECONL, 2<<DECWECONL, 2<<DECWECONL, 2<<DECWECONL,
+ 0, 0, 1<<DECWECONL, 1<<DECWECONL,
+ 2<<DECWECONL, 2<<DECWECONL, DECFLOAT_Inf, DECFLOAT_NaN};
+#endif
+
+#if QUAD
+const uInt DECCOMBMSD[64]={
+ 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,
+ 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, 0};
+
+const uInt DECCOMBFROM[48]={
+ 0x00000000, 0x04000000, 0x08000000, 0x0C000000, 0x10000000, 0x14000000,
+ 0x18000000, 0x1C000000, 0x60000000, 0x64000000, 0x00000000, 0x00000000,
+ 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x20000000, 0x24000000,
+ 0x28000000, 0x2C000000, 0x30000000, 0x34000000, 0x38000000, 0x3C000000,
+ 0x68000000, 0x6C000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000,
+ 0x00000000, 0x00000000, 0x40000000, 0x44000000, 0x48000000, 0x4C000000,
+ 0x50000000, 0x54000000, 0x58000000, 0x5C000000, 0x70000000, 0x74000000,
+ 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000};
+
+/* ------------------------------------------------------------------ */
+/* Request and include the tables to use for conversions */
+/* ------------------------------------------------------------------ */
+#define DEC_BCD2DPD 1 /* 0-0x999 -> DPD */
+#define DEC_BIN2DPD 1 /* 0-999 -> DPD */
+#define DEC_BIN2BCD8 1 /* 0-999 -> ddd, len */
+#define DEC_DPD2BCD8 1 /* DPD -> ddd, len */
+#define DEC_DPD2BIN 1 /* DPD -> 0-999 */
+#define DEC_DPD2BINK 1 /* DPD -> 0-999000 */
+#define DEC_DPD2BINM 1 /* DPD -> 0-999000000 */
+#include "decDPD.h" /* source of the lookup tables */
+
+#endif
+
+/* ----------------------------------------------------------------- */
+/* decBiStr -- compare string with pairwise options */
+/* */
+/* targ is the string to compare */
+/* str1 is one of the strings to compare against (length may be 0) */
+/* str2 is the other; it must be the same length as str1 */
+/* */
+/* returns 1 if strings compare equal, (that is, targ is the same */
+/* length as str1 and str2, and each character of targ is in one */
+/* of str1 or str2 in the corresponding position), or 0 otherwise */
+/* */
+/* This is used for generic caseless compare, including the awkward */
+/* case of the Turkish dotted and dotless Is. Use as (for example): */
+/* if (decBiStr(test, "mike", "MIKE")) ... */
+/* ----------------------------------------------------------------- */
+static Flag decBiStr(const char *targ, const char *str1, const char *str2) {
+ for (;;targ++, str1++, str2++) {
+ if (*targ!=*str1 && *targ!=*str2) return 0;
+ /* *targ has a match in one (or both, if terminator) */
+ if (*targ=='\0') break;
+ } /* forever */
+ return 1;
+ } /* decBiStr */
+
+/* ------------------------------------------------------------------ */
+/* decFinalize -- adjust and store a final result */
+/* */
+/* df is the decFloat format number which gets the final result */
+/* num is the descriptor of the number to be checked and encoded */
+/* [its values, including the coefficient, may be modified] */
+/* set is the context to use */
+/* returns df */
+/* */
+/* The num descriptor may point to a bcd8 string of any length; this */
+/* string may have leading insignificant zeros. If it has more than */
+/* DECPMAX digits then the final digit can be a round-for-reround */
+/* digit (i.e., it may include a sticky bit residue). */
+/* */
+/* The exponent (q) may be one of the codes for a special value and */
+/* can be up to 999999999 for conversion from string. */
+/* */
+/* No error is possible, but Inexact, Underflow, and/or Overflow may */
+/* be set. */
+/* ------------------------------------------------------------------ */
+/* Constant whose size varies with format; also the check for surprises */
+static uByte allnines[DECPMAX]=
+#if SINGLE
+ {9, 9, 9, 9, 9, 9, 9};
+#elif DOUBLE
+ {9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9};
+#elif QUAD
+ {9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
+ 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9};
+#endif
+
+static decFloat * decFinalize(decFloat *df, bcdnum *num,
+ decContext *set) {
+ uByte *ub; /* work */
+ uInt dpd; /* .. */
+ uByte *umsd=num->msd; /* local copy */
+ uByte *ulsd=num->lsd; /* .. */
+ uInt encode; /* encoding accumulator */
+ Int length; /* coefficient length */
+
+ #if DECCHECK
+ Int clen=ulsd-umsd+1;
+ #if QUAD
+ #define COEXTRA 2 /* extra-long coefficent */
+ #else
+ #define COEXTRA 0
+ #endif
+ if (clen<1 || clen>DECPMAX*3+2+COEXTRA)
+ printf("decFinalize: suspect coefficient [length=%ld]\n", (LI)clen);
+ if (num->sign!=0 && num->sign!=DECFLOAT_Sign)
+ printf("decFinalize: bad sign [%08lx]\n", (LI)num->sign);
+ if (!EXPISSPECIAL(num->exponent)
+ && (num->exponent>1999999999 || num->exponent<-1999999999))
+ printf("decFinalize: improbable exponent [%ld]\n", (LI)num->exponent);
+ /* decShowNum(num, "final"); */
+ #endif
+
+ /* A special will have an 'exponent' which is very positive and a */
+ /* coefficient < DECPMAX */
+ length=(uInt)(ulsd-umsd+1); /* coefficient length */
+
+ if (!NUMISSPECIAL(num)) {
+ Int drop; /* digits to be dropped */
+ /* skip leading insignificant zeros to calculate an exact length */
+ /* [this is quite expensive] */
+ if (*umsd==0) {
+ for (; UINTAT(umsd)==0 && umsd+3<ulsd;) umsd+=4;
+ for (; *umsd==0 && umsd<ulsd;) umsd++;
+ length=ulsd-umsd+1; /* recalculate */
+ }
+ drop=MAXI(length-DECPMAX, DECQTINY-num->exponent);
+ /* drop can now be > digits for bottom-clamp (subnormal) cases */
+ if (drop>0) { /* rounding needed */
+ /* (decFloatQuantize has very similar code to this, so any */
+ /* changes may need to be made there, too) */
+ uByte *roundat; /* -> re-round digit */
+ uByte reround; /* reround value */
+ /* printf("Rounding; drop=%ld\n", (LI)drop); */
+
+ num->exponent+=drop; /* always update exponent */
+
+ /* Three cases here: */
+ /* 1. new LSD is in coefficient (almost always) */
+ /* 2. new LSD is digit to left of coefficient (so MSD is */
+ /* round-for-reround digit) */
+ /* 3. new LSD is to left of case 2 (whole coefficient is sticky) */
+ /* [duplicate check-stickies code to save a test] */
+ /* [by-digit check for stickies as runs of zeros are rare] */
+ if (drop<length) { /* NB lengths not addresses */
+ roundat=umsd+length-drop;
+ reround=*roundat;
+ for (ub=roundat+1; ub<=ulsd; ub++) {
+ if (*ub!=0) { /* non-zero to be discarded */
+ reround=DECSTICKYTAB[reround]; /* apply sticky bit */
+ break; /* [remainder don't-care] */
+ }
+ } /* check stickies */
+ ulsd=roundat-1; /* new LSD */
+ }
+ else { /* edge case */
+ if (drop==length) {
+ roundat=umsd;
+ reround=*roundat;
+ }
+ else {
+ roundat=umsd-1;
+ reround=0;
+ }
+ for (ub=roundat+1; ub<=ulsd; ub++) {
+ if (*ub!=0) { /* non-zero to be discarded */
+ reround=DECSTICKYTAB[reround]; /* apply sticky bit */
+ break; /* [remainder don't-care] */
+ }
+ } /* check stickies */
+ *umsd=0; /* coefficient is a 0 */
+ ulsd=umsd; /* .. */
+ }
+
+ if (reround!=0) { /* discarding non-zero */
+ uInt bump=0;
+ set->status|=DEC_Inexact;
+ /* if adjusted exponent [exp+digits-1] is < EMIN then num is */
+ /* subnormal -- so raise Underflow */
+ if (num->exponent<DECEMIN && (num->exponent+(ulsd-umsd+1)-1)<DECEMIN)
+ set->status|=DEC_Underflow;
+
+ /* next decide whether increment of the coefficient is needed */
+ if (set->round==DEC_ROUND_HALF_EVEN) { /* fastpath slowest case */
+ if (reround>5) bump=1; /* >0.5 goes up */
+ else if (reround==5) /* exactly 0.5000 .. */
+ bump=*ulsd & 0x01; /* .. up iff [new] lsd is odd */
+ } /* r-h-e */
+ else switch (set->round) {
+ case DEC_ROUND_DOWN: {
+ /* no change */
+ break;} /* r-d */
+ case DEC_ROUND_HALF_DOWN: {
+ if (reround>5) bump=1;
+ break;} /* r-h-d */
+ case DEC_ROUND_HALF_UP: {
+ if (reround>=5) bump=1;
+ break;} /* r-h-u */
+ case DEC_ROUND_UP: {
+ if (reround>0) bump=1;
+ break;} /* r-u */
+ case DEC_ROUND_CEILING: {
+ /* same as _UP for positive numbers, and as _DOWN for negatives */
+ if (!num->sign && reround>0) bump=1;
+ break;} /* r-c */
+ case DEC_ROUND_FLOOR: {
+ /* same as _UP for negative numbers, and as _DOWN for positive */
+ /* [negative reround cannot occur on 0] */
+ if (num->sign && reround>0) bump=1;
+ break;} /* r-f */
+ case DEC_ROUND_05UP: {
+ if (reround>0) { /* anything out there is 'sticky' */
+ /* bump iff lsd=0 or 5; this cannot carry so it could be */
+ /* effected immediately with no bump -- but the code */
+ /* is clearer if this is done the same way as the others */
+ if (*ulsd==0 || *ulsd==5) bump=1;
+ }
+ break;} /* r-r */
+ default: { /* e.g., DEC_ROUND_MAX */
+ set->status|=DEC_Invalid_context;
+ #if DECCHECK
+ printf("Unknown rounding mode: %ld\n", (LI)set->round);
+ #endif
+ break;}
+ } /* switch (not r-h-e) */
+ /* printf("ReRound: %ld bump: %ld\n", (LI)reround, (LI)bump); */
+
+ if (bump!=0) { /* need increment */
+ /* increment the coefficient; this might end up with 1000... */
+ /* (after the all nines case) */
+ ub=ulsd;
+ for(; ub-3>=umsd && UINTAT(ub-3)==0x09090909; ub-=4) UINTAT(ub-3)=0;
+ /* [note ub could now be to left of msd, and it is not safe */
+ /* to write to the the left of the msd] */
+ /* now at most 3 digits left to non-9 (usually just the one) */
+ for (; ub>=umsd; *ub=0, ub--) {
+ if (*ub==9) continue; /* carry */
+ *ub+=1;
+ break;
+ }
+ if (ub<umsd) { /* had all-nines */
+ *umsd=1; /* coefficient to 1000... */
+ /* usually the 1000... coefficient can be used as-is */
+ if ((ulsd-umsd+1)==DECPMAX) {
+ num->exponent++;
+ }
+ else {
+ /* if coefficient is shorter than Pmax then num is */
+ /* subnormal, so extend it; this is safe as drop>0 */
+ /* (or, if the coefficient was supplied above, it could */
+ /* not be 9); this may make the result normal. */
+ ulsd++;
+ *ulsd=0;
+ /* [exponent unchanged] */
+ #if DECCHECK
+ if (num->exponent!=DECQTINY) /* sanity check */
+ printf("decFinalize: bad all-nines extend [^%ld, %ld]\n",
+ (LI)num->exponent, (LI)(ulsd-umsd+1));
+ #endif
+ } /* subnormal extend */
+ } /* had all-nines */
+ } /* bump needed */
+ } /* inexact rounding */
+
+ length=ulsd-umsd+1; /* recalculate (may be <DECPMAX) */
+ } /* need round (drop>0) */
+
+ /* The coefficient will now fit and has final length unless overflow */
+ /* decShowNum(num, "rounded"); */
+
+ /* if exponent is >=emax may have to clamp, overflow, or fold-down */
+ if (num->exponent>DECEMAX-(DECPMAX-1)) { /* is edge case */
+ /* printf("overflow checks...\n"); */
+ if (*ulsd==0 && ulsd==umsd) { /* have zero */
+ num->exponent=DECEMAX-(DECPMAX-1); /* clamp to max */
+ }
+ else if ((num->exponent+length-1)>DECEMAX) { /* > Nmax */
+ /* Overflow -- these could go straight to encoding, here, but */
+ /* instead num is adjusted to keep the code cleaner */
+ Flag needmax=0; /* 1 for finite result */
+ set->status|=(DEC_Overflow | DEC_Inexact);
+ switch (set->round) {
+ case DEC_ROUND_DOWN: {
+ needmax=1; /* never Infinity */
+ break;} /* r-d */
+ case DEC_ROUND_05UP: {
+ needmax=1; /* never Infinity */
+ break;} /* r-05 */
+ case DEC_ROUND_CEILING: {
+ if (num->sign) needmax=1; /* Infinity iff non-negative */
+ break;} /* r-c */
+ case DEC_ROUND_FLOOR: {
+ if (!num->sign) needmax=1; /* Infinity iff negative */
+ break;} /* r-f */
+ default: break; /* Infinity in all other cases */
+ }
+ if (!needmax) { /* easy .. set Infinity */
+ num->exponent=DECFLOAT_Inf;
+ *umsd=0; /* be clean: coefficient to 0 */
+ ulsd=umsd; /* .. */
+ }
+ else { /* return Nmax */
+ umsd=allnines; /* use constant array */
+ ulsd=allnines+DECPMAX-1;
+ num->exponent=DECEMAX-(DECPMAX-1);
+ }
+ }
+ else { /* no overflow but non-zero and may have to fold-down */
+ Int shift=num->exponent-(DECEMAX-(DECPMAX-1));
+ if (shift>0) { /* fold-down needed */
+ /* fold down needed; must copy to buffer in order to pad */
+ /* with zeros safely; fortunately this is not the worst case */
+ /* path because cannot have had a round */
+ uByte buffer[ROUNDUP(DECPMAX+3, 4)]; /* [+3 allows uInt padding] */
+ uByte *s=umsd; /* source */
+ uByte *t=buffer; /* safe target */
+ uByte *tlsd=buffer+(ulsd-umsd)+shift; /* target LSD */
+ /* printf("folddown shift=%ld\n", (LI)shift); */
+ for (; s<=ulsd; s+=4, t+=4) UINTAT(t)=UINTAT(s);
+ for (t=tlsd-shift+1; t<=tlsd; t+=4) UINTAT(t)=0; /* pad */
+ num->exponent-=shift;
+ umsd=buffer;
+ ulsd=tlsd;
+ }
+ } /* fold-down? */
+ length=ulsd-umsd+1; /* recalculate length */
+ } /* high-end edge case */
+ } /* finite number */
+
+ /*------------------------------------------------------------------*/
+ /* At this point the result will properly fit the decFloat */
+ /* encoding, and it can be encoded with no possibility of error */
+ /*------------------------------------------------------------------*/
+ /* Following code does not alter coefficient (could be allnines array) */
+
+ if (length==DECPMAX) {
+ return decFloatFromBCD(df, num->exponent, umsd, num->sign);
+ }
+
+ /* Here when length is short */
+ if (!NUMISSPECIAL(num)) { /* is still finite */
+ /* encode the combination field and exponent continuation */
+ uInt uexp=(uInt)(num->exponent+DECBIAS); /* biased exponent */
+ uInt code=(uexp>>DECECONL)<<4; /* top two bits of exp */
+ /* [msd=0] */
+ /* look up the combination field and make high word */
+ encode=DECCOMBFROM[code]; /* indexed by (0-2)*16+msd */
+ encode|=(uexp<<(32-6-DECECONL)) & 0x03ffffff; /* exponent continuation */
+ }
+ else encode=num->exponent; /* special [already in word] */
+ /* [coefficient length here will be < DECPMAX] */
+
+ encode|=num->sign; /* add sign */
+
+ /* private macro to extract a declet, n (where 0<=n<DECLETS and 0 */
+ /* refers to the declet from the least significant three digits) */
+ /* and put the corresponding DPD code into dpd. Access to umsd and */
+ /* ulsd (pointers to the most and least significant digit of the */
+ /* variable-length coefficient) is assumed, along with use of a */
+ /* working pointer, uInt *ub. */
+ /* As not full-length then chances are there are many leading zeros */
+ /* [and there may be a partial triad] */
+ #define getDPD(dpd, n) ub=ulsd-(3*(n))-2; \
+ if (ub<umsd-2) dpd=0; \
+ else if (ub>=umsd) dpd=BCD2DPD[(*ub*256)+(*(ub+1)*16)+*(ub+2)]; \
+ else {dpd=*(ub+2); if (ub+1==umsd) dpd+=*(ub+1)*16; dpd=BCD2DPD[dpd];}
+
+ /* place the declets in the encoding words and copy to result (df), */
+ /* according to endianness; in all cases complete the sign word */
+ /* first */
+ #if DECPMAX==7
+ getDPD(dpd, 1);
+ encode|=dpd<<10;
+ getDPD(dpd, 0);
+ encode|=dpd;
+ DFWORD(df, 0)=encode; /* just the one word */
+
+ #elif DECPMAX==16
+ getDPD(dpd, 4); encode|=dpd<<8;
+ getDPD(dpd, 3); encode|=dpd>>2;
+ DFWORD(df, 0)=encode;
+ encode=dpd<<30;
+ getDPD(dpd, 2); encode|=dpd<<20;
+ getDPD(dpd, 1); encode|=dpd<<10;
+ getDPD(dpd, 0); encode|=dpd;
+ DFWORD(df, 1)=encode;
+
+ #elif DECPMAX==34
+ getDPD(dpd,10); encode|=dpd<<4;
+ getDPD(dpd, 9); encode|=dpd>>6;
+ DFWORD(df, 0)=encode;
+
+ encode=dpd<<26;
+ getDPD(dpd, 8); encode|=dpd<<16;
+ getDPD(dpd, 7); encode|=dpd<<6;
+ getDPD(dpd, 6); encode|=dpd>>4;
+ DFWORD(df, 1)=encode;
+
+ encode=dpd<<28;
+ getDPD(dpd, 5); encode|=dpd<<18;
+ getDPD(dpd, 4); encode|=dpd<<8;
+ getDPD(dpd, 3); encode|=dpd>>2;
+ DFWORD(df, 2)=encode;
+
+ encode=dpd<<30;
+ getDPD(dpd, 2); encode|=dpd<<20;
+ getDPD(dpd, 1); encode|=dpd<<10;
+ getDPD(dpd, 0); encode|=dpd;
+ DFWORD(df, 3)=encode;
+ #endif
+
+ /* printf("Status: %08lx\n", (LI)set->status); */
+ /* decFloatShow(df, "final"); */
+ return df;
+ } /* decFinalize */
+
+/* ------------------------------------------------------------------ */
+/* decFloatFromBCD -- set decFloat from exponent, BCD8, and sign */
+/* */
+/* df is the target decFloat */
+/* exp is the in-range unbiased exponent, q, or a special value in */
+/* the form returned by decFloatGetExponent */
+/* bcdar holds DECPMAX digits to set the coefficient from, one */
+/* digit in each byte (BCD8 encoding); the first (MSD) is ignored */
+/* if df is a NaN; all are ignored if df is infinite. */
+/* All bytes must be in 0-9; results undefined otherwise. */
+/* sig is DECFLOAT_Sign to set the sign bit, 0 otherwise */
+/* returns df, which will be canonical */
+/* */
+/* No error is possible, and no status will be set. */
+/* ------------------------------------------------------------------ */
+decFloat * decFloatFromBCD(decFloat *df, Int exp, const uByte *bcdar,
+ Int sig) {
+ uInt encode, dpd; /* work */
+ const uByte *ub; /* .. */
+
+ if (EXPISSPECIAL(exp)) encode=exp|sig;/* specials already encoded */
+ else { /* is finite */
+ /* encode the combination field and exponent continuation */
+ uInt uexp=(uInt)(exp+DECBIAS); /* biased exponent */
+ uInt code=(uexp>>DECECONL)<<4; /* top two bits of exp */
+ code+=bcdar[0]; /* add msd */
+ /* look up the combination field and make high word */
+ encode=DECCOMBFROM[code]|sig; /* indexed by (0-2)*16+msd */
+ encode|=(uexp<<(32-6-DECECONL)) & 0x03ffffff; /* exponent continuation */
+ }
+
+ /* private macro to extract a declet, n (where 0<=n<DECLETS and 0 */
+ /* refers to the declet from the least significant three digits) */
+ /* and put the corresponding DPD code into dpd. */
+ /* Use of a working pointer, uInt *ub, is assumed. */
+
+ #define getDPDf(dpd, n) ub=bcdar+DECPMAX-1-(3*(n))-2; \
+ dpd=BCD2DPD[(*ub*256)+(*(ub+1)*16)+*(ub+2)];
+
+ /* place the declets in the encoding words and copy to result (df), */
+ /* according to endianness; in all cases complete the sign word */
+ /* first */
+ #if DECPMAX==7
+ getDPDf(dpd, 1);
+ encode|=dpd<<10;
+ getDPDf(dpd, 0);
+ encode|=dpd;
+ DFWORD(df, 0)=encode; /* just the one word */
+
+ #elif DECPMAX==16
+ getDPDf(dpd, 4); encode|=dpd<<8;
+ getDPDf(dpd, 3); encode|=dpd>>2;
+ DFWORD(df, 0)=encode;
+ encode=dpd<<30;
+ getDPDf(dpd, 2); encode|=dpd<<20;
+ getDPDf(dpd, 1); encode|=dpd<<10;
+ getDPDf(dpd, 0); encode|=dpd;
+ DFWORD(df, 1)=encode;
+
+ #elif DECPMAX==34
+ getDPDf(dpd,10); encode|=dpd<<4;
+ getDPDf(dpd, 9); encode|=dpd>>6;
+ DFWORD(df, 0)=encode;
+
+ encode=dpd<<26;
+ getDPDf(dpd, 8); encode|=dpd<<16;
+ getDPDf(dpd, 7); encode|=dpd<<6;
+ getDPDf(dpd, 6); encode|=dpd>>4;
+ DFWORD(df, 1)=encode;
+
+ encode=dpd<<28;
+ getDPDf(dpd, 5); encode|=dpd<<18;
+ getDPDf(dpd, 4); encode|=dpd<<8;
+ getDPDf(dpd, 3); encode|=dpd>>2;
+ DFWORD(df, 2)=encode;
+
+ encode=dpd<<30;
+ getDPDf(dpd, 2); encode|=dpd<<20;
+ getDPDf(dpd, 1); encode|=dpd<<10;
+ getDPDf(dpd, 0); encode|=dpd;
+ DFWORD(df, 3)=encode;
+ #endif
+ /* decFloatShow(df, "final"); */
+ return df;
+ } /* decFloatFromBCD */
+
+/* ------------------------------------------------------------------ */
+/* decFloatFromPacked -- set decFloat from exponent and packed BCD */
+/* */
+/* df is the target decFloat */
+/* exp is the in-range unbiased exponent, q, or a special value in */
+/* the form returned by decFloatGetExponent */
+/* packed holds DECPMAX packed decimal digits plus a sign nibble */
+/* (all 6 codes are OK); the first (MSD) is ignored if df is a NaN */
+/* and all except sign are ignored if df is infinite. For DOUBLE */
+/* and QUAD the first (pad) nibble is also ignored in all cases. */
+/* All coefficient nibbles must be in 0-9 and sign in A-F; results */
+/* are undefined otherwise. */
+/* returns df, which will be canonical */
+/* */
+/* No error is possible, and no status will be set. */
+/* ------------------------------------------------------------------ */
+decFloat * decFloatFromPacked(decFloat *df, Int exp, const uByte *packed) {
+ uByte bcdar[DECPMAX+2]; /* work [+1 for pad, +1 for sign] */
+ const uByte *ip; /* .. */
+ uByte *op; /* .. */
+ Int sig=0; /* sign */
+
+ /* expand coefficient and sign to BCDAR */
+ #if SINGLE
+ op=bcdar+1; /* no pad digit */
+ #else
+ op=bcdar; /* first (pad) digit ignored */
+ #endif
+ for (ip=packed; ip<packed+((DECPMAX+2)/2); ip++) {
+ *op++=*ip>>4;
+ *op++=(uByte)(*ip&0x0f); /* [final nibble is sign] */
+ }
+ op--; /* -> sign byte */
+ if (*op==DECPMINUS || *op==DECPMINUSALT) sig=DECFLOAT_Sign;
+
+ if (EXPISSPECIAL(exp)) { /* Infinity or NaN */
+ if (!EXPISINF(exp)) bcdar[1]=0; /* a NaN: ignore MSD */
+ else memset(bcdar+1, 0, DECPMAX); /* Infinite: coefficient to 0 */
+ }
+ return decFloatFromBCD(df, exp, bcdar+1, sig);
+ } /* decFloatFromPacked */
+
+/* ------------------------------------------------------------------ */
+/* decFloatFromString -- conversion from numeric string */
+/* */
+/* result is the decFloat 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), \0-terminated */
+/* If there are too many significant digits in the */
+/* coefficient it will be rounded. */
+/* set is the context */
+/* returns result */
+/* */
+/* The length of the coefficient and the size of the exponent are */
+/* checked by this routine, so the correct error (Underflow or */
+/* Overflow) can be reported or rounding applied, as necessary. */
+/* */
+/* There is no limit to the coefficient length for finite inputs; */
+/* NaN payloads must be integers with no more than DECPMAX-1 digits. */
+/* Exponents may have up to nine significant digits. */
+/* */
+/* If bad syntax is detected, the result will be a quiet NaN. */
+/* ------------------------------------------------------------------ */
+decFloat * decFloatFromString(decFloat *result, const char *string,
+ decContext *set) {
+ Int digits; /* count of digits in coefficient */
+ const char *dotchar=NULL; /* where dot was found [NULL if none] */
+ const char *cfirst=string; /* -> first character of decimal part */
+ const char *c; /* work */
+ uByte *ub; /* .. */
+ bcdnum num; /* collects data for finishing */
+ uInt error=DEC_Conversion_syntax; /* assume the worst */
+ uByte buffer[ROUNDUP(DECSTRING+11, 8)]; /* room for most coefficents, */
+ /* some common rounding, +3, & pad */
+ #if DECTRACE
+ /* printf("FromString %s ...\n", string); */
+ #endif
+
+ for(;;) { /* once-only 'loop' */
+ num.sign=0; /* assume non-negative */
+ num.msd=buffer; /* MSD is here always */
+
+ /* detect and validate the coefficient, including any leading, */
+ /* trailing, or embedded '.' */
+ /* [could test four-at-a-time here (saving 10% for decQuads), */
+ /* but that risks storage violation because the position of the */
+ /* terminator is unknown] */
+ for (c=string;; c++) { /* -> input character */
+ if (((unsigned)(*c-'0'))<=9) continue; /* '0' through '9' is good */
+ if (*c=='\0') break; /* most common non-digit */
+ if (*c=='.') {
+ if (dotchar!=NULL) break; /* not first '.' */
+ dotchar=c; /* record offset into decimal part */
+ continue;}
+ if (c==string) { /* first in string... */
+ if (*c=='-') { /* valid - sign */
+ cfirst++;
+ num.sign=DECFLOAT_Sign;
+ continue;}
+ if (*c=='+') { /* valid + sign */
+ cfirst++;
+ continue;}
+ }
+ /* *c is not a digit, terminator, or a valid +, -, or '.' */
+ break;
+ } /* c loop */
+
+ digits=(uInt)(c-cfirst); /* digits (+1 if a dot) */
+
+ if (digits>0) { /* had digits and/or dot */
+ const char *clast=c-1; /* note last coefficient char position */
+ Int exp=0; /* exponent accumulator */
+ if (*c!='\0') { /* something follows the coefficient */
+ uInt edig; /* unsigned work */
+ /* had some digits and more to come; expect E[+|-]nnn now */
+ const char *firstexp; /* exponent first non-zero */
+ if (*c!='E' && *c!='e') break;
+ c++; /* to (optional) sign */
+ if (*c=='-' || *c=='+') c++; /* step over sign (c=clast+2) */
+ if (*c=='\0') break; /* no digits! (e.g., '1.2E') */
+ for (; *c=='0';) c++; /* skip leading zeros [even last] */
+ firstexp=c; /* remember start [maybe '\0'] */
+ /* gather exponent digits */
+ edig=(uInt)*c-(uInt)'0';
+ if (edig<=9) { /* [check not bad or terminator] */
+ exp+=edig; /* avoid initial X10 */
+ c++;
+ for (;; c++) {
+ edig=(uInt)*c-(uInt)'0';
+ if (edig>9) break;
+ exp=exp*10+edig;
+ }
+ }
+ /* if not now on the '\0', *c must not be a digit */
+ if (*c!='\0') break;
+
+ /* (this next test must be after the syntax checks) */
+ /* if definitely more than the possible digits for format then */
+ /* the exponent may have wrapped, so simply set it to a certain */
+ /* over/underflow value */
+ if (c>firstexp+DECEMAXD) exp=DECEMAX*2;
+ if (*(clast+2)=='-') exp=-exp; /* was negative */
+ } /* digits>0 */
+
+ if (dotchar!=NULL) { /* had a '.' */
+ digits--; /* remove from digits count */
+ if (digits==0) break; /* was dot alone: bad syntax */
+ exp-=(Int)(clast-dotchar); /* adjust exponent */
+ /* [the '.' can now be ignored] */
+ }
+ num.exponent=exp; /* exponent is good; store it */
+
+ /* Here when whole string has been inspected and syntax is good */
+ /* cfirst->first digit or dot, clast->last digit or dot */
+ error=0; /* no error possible now */
+
+ /* if the number of digits in the coefficient will fit in buffer */
+ /* then it can simply be converted to bcd8 and copied -- decFinalize */
+ /* will take care of leading zeros and rounding; the buffer is big */
+ /* enough for all canonical coefficients, including 0.00000nn... */
+ ub=buffer;
+ if (digits<=(Int)(sizeof(buffer)-3)) { /* [-3 allows by-4s copy] */
+ c=cfirst;
+ if (dotchar!=NULL) { /* a dot to worry about */
+ if (*(c+1)=='.') { /* common canonical case */
+ *ub++=(uByte)(*c-'0'); /* copy leading digit */
+ c+=2; /* prepare to handle rest */
+ }
+ else for (; c<=clast;) { /* '.' could be anywhere */
+ /* as usual, go by fours when safe; NB it has been asserted */
+ /* that a '.' does not have the same mask as a digit */
+ if (c<=clast-3 /* safe for four */
+ && (UINTAT(c)&0xf0f0f0f0)==CHARMASK) { /* test four */
+ UINTAT(ub)=UINTAT(c)&0x0f0f0f0f; /* to BCD8 */
+ ub+=4;
+ c+=4;
+ continue;
+ }
+ if (*c=='.') { /* found the dot */
+ c++; /* step over it .. */
+ break; /* .. and handle the rest */
+ }
+ *ub++=(uByte)(*c++-'0');
+ }
+ } /* had dot */
+ /* Now no dot; do this by fours (where safe) */
+ for (; c<=clast-3; c+=4, ub+=4) UINTAT(ub)=UINTAT(c)&0x0f0f0f0f;
+ for (; c<=clast; c++, ub++) *ub=(uByte)(*c-'0');
+ num.lsd=buffer+digits-1; /* record new LSD */
+ } /* fits */
+
+ else { /* too long for buffer */
+ /* [This is a rare and unusual case; arbitrary-length input] */
+ /* strip leading zeros [but leave final 0 if all 0's] */
+ if (*cfirst=='.') cfirst++; /* step past dot at start */
+ if (*cfirst=='0') { /* [cfirst always -> digit] */
+ for (; cfirst<clast; cfirst++) {
+ if (*cfirst!='0') { /* non-zero found */
+ if (*cfirst=='.') continue; /* [ignore] */
+ break; /* done */
+ }
+ digits--; /* 0 stripped */
+ } /* cfirst */
+ } /* at least one leading 0 */
+
+ /* the coefficient is now as short as possible, but may still */
+ /* be too long; copy up to Pmax+1 digits to the buffer, then */
+ /* just record any non-zeros (set round-for-reround digit) */
+ for (c=cfirst; c<=clast && ub<=buffer+DECPMAX; c++) {
+ /* (see commentary just above) */
+ if (c<=clast-3 /* safe for four */
+ && (UINTAT(c)&0xf0f0f0f0)==CHARMASK) { /* four digits */
+ UINTAT(ub)=UINTAT(c)&0x0f0f0f0f; /* to BCD8 */
+ ub+=4;
+ c+=3; /* [will become 4] */
+ continue;
+ }
+ if (*c=='.') continue; /* [ignore] */
+ *ub++=(uByte)(*c-'0');
+ }
+ ub--; /* -> LSD */
+ for (; c<=clast; c++) { /* inspect remaining chars */
+ if (*c!='0') { /* sticky bit needed */
+ if (*c=='.') continue; /* [ignore] */
+ *ub=DECSTICKYTAB[*ub]; /* update round-for-reround */
+ break; /* no need to look at more */
+ }
+ }
+ num.lsd=ub; /* record LSD */
+ /* adjust exponent for dropped digits */
+ num.exponent+=digits-(Int)(ub-buffer+1);
+ } /* too long for buffer */
+ } /* digits or dot */
+
+ else { /* no digits or dot were found */
+ if (*c=='\0') break; /* nothing to come is bad */
+ /* only Infinities and NaNs are allowed, here */
+ buffer[0]=0; /* default a coefficient of 0 */
+ num.lsd=buffer; /* .. */
+ if (decBiStr(c, "infinity", "INFINITY")
+ || decBiStr(c, "inf", "INF")) num.exponent=DECFLOAT_Inf;
+ else { /* should be a NaN */
+ num.exponent=DECFLOAT_qNaN; /* assume quiet NaN */
+ if (*c=='s' || *c=='S') { /* probably an sNaN */
+ c++;
+ num.exponent=DECFLOAT_sNaN; /* assume is in fact sNaN */
+ }
+ if (*c!='N' && *c!='n') break; /* check caseless "NaN" */
+ c++;
+ if (*c!='a' && *c!='A') break; /* .. */
+ c++;
+ if (*c!='N' && *c!='n') break; /* .. */
+ c++;
+ /* now either nothing, or nnnn payload (no dots), expected */
+ /* -> start of integer, and skip leading 0s [including plain 0] */
+ for (cfirst=c; *cfirst=='0';) cfirst++;
+ if (*cfirst!='\0') { /* not empty or all-0, payload */
+ /* payload found; check all valid digits and copy to buffer as bcd8 */
+ ub=buffer;
+ for (c=cfirst;; c++, ub++) {
+ if ((unsigned)(*c-'0')>9) break; /* quit if not 0-9 */
+ if (c-cfirst==DECPMAX-1) break; /* too many digits */
+ *ub=(uByte)(*c-'0'); /* good bcd8 */
+ }
+ if (*c!='\0') break; /* not all digits, or too many */
+ num.lsd=ub-1; /* record new LSD */
+ }
+ } /* NaN or sNaN */
+ error=0; /* syntax is OK */
+ break; /* done with specials */
+ } /* digits=0 (special expected) */
+ break;
+ } /* [for(;;) break] */
+
+ /* decShowNum(&num, "fromStr"); */
+
+ if (error!=0) {
+ set->status|=error;
+ num.exponent=DECFLOAT_qNaN; /* set up quiet NaN */
+ num.sign=0; /* .. with 0 sign */
+ buffer[0]=0; /* .. and coefficient */
+ num.lsd=buffer; /* .. */
+ /* decShowNum(&num, "oops"); */
+ }
+
+ /* decShowNum(&num, "dffs"); */
+ decFinalize(result, &num, set); /* round, check, and lay out */
+ /* decFloatShow(result, "fromString"); */
+ return result;
+ } /* decFloatFromString */
+
+/* ------------------------------------------------------------------ */
+/* decFloatFromWider -- conversion from next-wider format */
+/* */
+/* result is the decFloat format number which gets the result of */
+/* the conversion */
+/* wider is the decFloatWider format number which will be narrowed */
+/* set is the context */
+/* returns result */
+/* */
+/* Narrowing can cause rounding, overflow, etc., but not Invalid */
+/* operation (sNaNs are copied and do not signal). */
+/* ------------------------------------------------------------------ */
+/* narrow-to is not possible for decQuad format numbers; simply omit */
+#if !QUAD
+decFloat * decFloatFromWider(decFloat *result, const decFloatWider *wider,
+ decContext *set) {
+ bcdnum num; /* collects data for finishing */
+ uByte bcdar[DECWPMAX]; /* room for wider coefficient */
+ uInt widerhi=DFWWORD(wider, 0); /* top word */
+ Int exp;
+
+ GETWCOEFF(wider, bcdar);
+
+ num.msd=bcdar; /* MSD is here always */
+ num.lsd=bcdar+DECWPMAX-1; /* LSD is here always */
+ num.sign=widerhi&0x80000000; /* extract sign [DECFLOAT_Sign=Neg] */
+
+ /* decode the wider combination field to exponent */
+ exp=DECCOMBWEXP[widerhi>>26]; /* decode from wider combination field */
+ /* if it is a special there's nothing to do unless sNaN; if it's */
+ /* finite then add the (wider) exponent continuation and unbias */
+ if (EXPISSPECIAL(exp)) exp=widerhi&0x7e000000; /* include sNaN selector */
+ else exp+=GETWECON(wider)-DECWBIAS;
+ num.exponent=exp;
+
+ /* decShowNum(&num, "dffw"); */
+ return decFinalize(result, &num, set);/* round, check, and lay out */
+ } /* decFloatFromWider */
+#endif
+
+/* ------------------------------------------------------------------ */
+/* decFloatGetCoefficient -- get coefficient as BCD8 */
+/* */
+/* df is the decFloat from which to extract the coefficient */
+/* bcdar is where DECPMAX bytes will be written, one BCD digit in */
+/* each byte (BCD8 encoding); if df is a NaN the first byte will */
+/* be zero, and if it is infinite they will all be zero */
+/* returns the sign of the coefficient (DECFLOAT_Sign if negative, */
+/* 0 otherwise) */
+/* */
+/* No error is possible, and no status will be set. If df is a */
+/* special value the array is set to zeros (for Infinity) or to the */
+/* payload of a qNaN or sNaN. */
+/* ------------------------------------------------------------------ */
+Int decFloatGetCoefficient(const decFloat *df, uByte *bcdar) {
+ if (DFISINF(df)) memset(bcdar, 0, DECPMAX);
+ else {
+ GETCOEFF(df, bcdar); /* use macro */
+ if (DFISNAN(df)) bcdar[0]=0; /* MSD needs correcting */
+ }
+ return DFISSIGNED(df);
+ } /* decFloatGetCoefficient */
+
+/* ------------------------------------------------------------------ */
+/* decFloatGetExponent -- get unbiased exponent */
+/* */
+/* df is the decFloat from which to extract the exponent */
+/* returns the exponent, q. */
+/* */
+/* No error is possible, and no status will be set. If df is a */
+/* special value the first seven bits of the decFloat are returned, */
+/* left adjusted and with the first (sign) bit set to 0 (followed by */
+/* 25 0 bits). e.g., -sNaN would return 0x7e000000 (DECFLOAT_sNaN). */
+/* ------------------------------------------------------------------ */
+Int decFloatGetExponent(const decFloat *df) {
+ if (DFISSPECIAL(df)) return DFWORD(df, 0)&0x7e000000;
+ return GETEXPUN(df);
+ } /* decFloatGetExponent */
+
+/* ------------------------------------------------------------------ */
+/* decFloatSetCoefficient -- set coefficient from BCD8 */
+/* */
+/* df is the target decFloat (and source of exponent/special value) */
+/* bcdar holds DECPMAX digits to set the coefficient from, one */
+/* digit in each byte (BCD8 encoding); the first (MSD) is ignored */
+/* if df is a NaN; all are ignored if df is infinite. */
+/* sig is DECFLOAT_Sign to set the sign bit, 0 otherwise */
+/* returns df, which will be canonical */
+/* */
+/* No error is possible, and no status will be set. */
+/* ------------------------------------------------------------------ */
+decFloat * decFloatSetCoefficient(decFloat *df, const uByte *bcdar,
+ Int sig) {
+ uInt exp; /* for exponent */
+ uByte bcdzero[DECPMAX]; /* for infinities */
+
+ /* Exponent/special code is extracted from df */
+ if (DFISSPECIAL(df)) {
+ exp=DFWORD(df, 0)&0x7e000000;
+ if (DFISINF(df)) {
+ memset(bcdzero, 0, DECPMAX);
+ return decFloatFromBCD(df, exp, bcdzero, sig);
+ }
+ }
+ else exp=GETEXPUN(df);
+ return decFloatFromBCD(df, exp, bcdar, sig);
+ } /* decFloatSetCoefficient */
+
+/* ------------------------------------------------------------------ */
+/* decFloatSetExponent -- set exponent or special value */
+/* */
+/* df is the target decFloat (and source of coefficient/payload) */
+/* set is the context for reporting status */
+/* exp is the unbiased exponent, q, or a special value in the form */
+/* returned by decFloatGetExponent */
+/* returns df, which will be canonical */
+/* */
+/* No error is possible, but Overflow or Underflow might occur. */
+/* ------------------------------------------------------------------ */
+decFloat * decFloatSetExponent(decFloat *df, decContext *set, Int exp) {
+ uByte bcdcopy[DECPMAX]; /* for coefficient */
+ bcdnum num; /* work */
+ num.exponent=exp;
+ num.sign=decFloatGetCoefficient(df, bcdcopy); /* extract coefficient */
+ if (DFISSPECIAL(df)) { /* MSD or more needs correcting */
+ if (DFISINF(df)) memset(bcdcopy, 0, DECPMAX);
+ bcdcopy[0]=0;
+ }
+ num.msd=bcdcopy;
+ num.lsd=bcdcopy+DECPMAX-1;
+ return decFinalize(df, &num, set);
+ } /* decFloatSetExponent */
+
+/* ------------------------------------------------------------------ */
+/* decFloatRadix -- returns the base (10) */
+/* */
+/* df is any decFloat of this format */
+/* ------------------------------------------------------------------ */
+uInt decFloatRadix(const decFloat *df) {
+ if (df) return 10; /* to placate compiler */
+ return 10;
+ } /* decFloatRadix */
+
+#if (DECCHECK || DECTRACE)
+/* ------------------------------------------------------------------ */
+/* decFloatShow -- printf a decFloat in hexadecimal and decimal */
+/* df is the decFloat to show */
+/* tag is a tag string displayed with the number */
+/* */
+/* This is a debug aid; the precise format of the string may change. */
+/* ------------------------------------------------------------------ */
+void decFloatShow(const decFloat *df, const char *tag) {
+ char hexbuf[DECBYTES*2+DECBYTES/4+1]; /* NB blank after every fourth */
+ char buff[DECSTRING]; /* for value in decimal */
+ Int i, j=0;
+
+ for (i=0; i<DECBYTES; i++) {
+ #if DECLITEND
+ sprintf(&hexbuf[j], "%02x", df->bytes[DECBYTES-1-i]);
+ #else
+ sprintf(&hexbuf[j], "%02x", df->bytes[i]);
+ #endif
+ j+=2;
+ /* the next line adds blank (and terminator) after final pair, too */
+ if ((i+1)%4==0) {strcpy(&hexbuf[j], " "); j++;}
+ }
+ decFloatToString(df, buff);
+ printf(">%s> %s [big-endian] %s\n", tag, hexbuf, buff);
+ return;
+ } /* decFloatShow */
+#endif
+
+/* ------------------------------------------------------------------ */
+/* decFloatToBCD -- get sign, exponent, and BCD8 from a decFloat */
+/* */
+/* df is the source decFloat */
+/* exp will be set to the unbiased exponent, q, or to a special */
+/* value in the form returned by decFloatGetExponent */
+/* bcdar is where DECPMAX bytes will be written, one BCD digit in */
+/* each byte (BCD8 encoding); if df is a NaN the first byte will */
+/* be zero, and if it is infinite they will all be zero */
+/* returns the sign of the coefficient (DECFLOAT_Sign if negative, */
+/* 0 otherwise) */
+/* */
+/* No error is possible, and no status will be set. */
+/* ------------------------------------------------------------------ */
+Int decFloatToBCD(const decFloat *df, Int *exp, uByte *bcdar) {
+ if (DFISINF(df)) {
+ memset(bcdar, 0, DECPMAX);
+ *exp=DFWORD(df, 0)&0x7e000000;
+ }
+ else {
+ GETCOEFF(df, bcdar); /* use macro */
+ if (DFISNAN(df)) {
+ bcdar[0]=0; /* MSD needs correcting */
+ *exp=DFWORD(df, 0)&0x7e000000;
+ }
+ else { /* finite */
+ *exp=GETEXPUN(df);
+ }
+ }
+ return DFISSIGNED(df);
+ } /* decFloatToBCD */
+
+/* ------------------------------------------------------------------ */
+/* decFloatToEngString -- conversion to numeric string, engineering */
+/* */
+/* df is the decFloat format number to convert */
+/* string is the string where the result will be laid out */
+/* */
+/* string must be at least DECPMAX+9 characters (the worst case is */
+/* "-0.00000nnn...nnn\0", which is as long as the exponent form when */
+/* DECEMAXD<=4); this condition is asserted above */
+/* */
+/* No error is possible, and no status will be set */
+/* ------------------------------------------------------------------ */
+char * decFloatToEngString(const decFloat *df, 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 */
+ char *s, *t; /* .. (source, target) */
+ Int pre, e; /* work */
+ const uByte *u; /* .. */
+
+ /* Source words; macro handles endianness */
+ uInt sourhi=DFWORD(df, 0); /* word with sign */
+ #if DECPMAX==16
+ uInt sourlo=DFWORD(df, 1);
+ #elif DECPMAX==34
+ uInt sourmh=DFWORD(df, 1);
+ uInt sourml=DFWORD(df, 2);
+ uInt sourlo=DFWORD(df, 3);
+ #endif
+
+ c=string; /* where result will go */
+ if (((Int)sourhi)<0) *c++='-'; /* handle sign */
+ comb=sourhi>>26; /* sign+combination field */
+ msd=DECCOMBMSD[comb]; /* decode the combination field */
+ exp=DECCOMBEXP[comb]; /* .. */
+
+ if (EXPISSPECIAL(exp)) { /* special */
+ if (exp==DECFLOAT_Inf) { /* 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 */
+ /* quick exit if the payload is zero */
+ #if DECPMAX==7
+ if ((sourhi&0x000fffff)==0) return string;
+ #elif DECPMAX==16
+ if (sourlo==0 && (sourhi&0x0003ffff)==0) return string;
+ #elif DECPMAX==34
+ if (sourlo==0 && sourml==0 && sourmh==0
+ && (sourhi&0x00003fff)==0) return string;
+ #endif
+ /* otherwise drop through to add integer; set correct exp etc. */
+ exp=0; msd=0; /* setup for following code */
+ }
+ else { /* complete exponent; top two bits are in place */
+ exp+=GETECON(df)-DECBIAS; /* .. + continuation and unbias */
+ }
+
+ /* convert the digits of the significand to characters */
+ cstart=c; /* save start of coefficient */
+ if (msd) *c++=(char)('0'+(char)msd); /* non-zero most significant digit */
+
+ /* Decode the declets. After extracting each declet, it is */
+ /* decoded to a 4-uByte sequence by table lookup; the four uBytes */
+ /* are the three encoded BCD8 digits followed by a 1-byte length */
+ /* (significant digits, except that 000 has length 0). This allows */
+ /* us to left-align the first declet with non-zero content, then */
+ /* the remaining ones are full 3-char length. Fixed-length copies */
+ /* are used because variable-length memcpy causes a subroutine call */
+ /* in at least two compilers. (The copies are length 4 for speed */
+ /* and are safe because the last item in the array is of length */
+ /* three and has the length byte following.) */
+ #define dpd2char(dpdin) u=&DPD2BCD8[((dpdin)&0x3ff)*4]; \
+ if (c!=cstart) {UINTAT(c)=UINTAT(u)|CHARMASK; c+=3;} \
+ else if (*(u+3)) { \
+ UINTAT(c)=UINTAT(u+3-*(u+3))|CHARMASK; c+=*(u+3);}
+
+ #if DECPMAX==7
+ dpd2char(sourhi>>10); /* declet 1 */
+ dpd2char(sourhi); /* declet 2 */
+
+ #elif DECPMAX==16
+ dpd2char(sourhi>>8); /* declet 1 */
+ dpd2char((sourhi<<2) | (sourlo>>30)); /* declet 2 */
+ dpd2char(sourlo>>20); /* declet 3 */
+ dpd2char(sourlo>>10); /* declet 4 */
+ dpd2char(sourlo); /* declet 5 */
+
+ #elif DECPMAX==34
+ dpd2char(sourhi>>4); /* declet 1 */
+ dpd2char((sourhi<<6) | (sourmh>>26)); /* declet 2 */
+ dpd2char(sourmh>>16); /* declet 3 */
+ dpd2char(sourmh>>6); /* declet 4 */
+ dpd2char((sourmh<<4) | (sourml>>28)); /* declet 5 */
+ dpd2char(sourml>>18); /* declet 6 */
+ dpd2char(sourml>>8); /* declet 7 */
+ dpd2char((sourml<<2) | (sourlo>>30)); /* declet 8 */
+ dpd2char(sourlo>>20); /* declet 9 */
+ dpd2char(sourlo>>10); /* declet 10 */
+ dpd2char(sourlo); /* declet 11 */
+ #endif
+
+ if (c==cstart) *c++='0'; /* all zeros, empty -- make "0" */
+
+ if (exp==0) { /* integer or NaN case -- easy */
+ *c='\0'; /* terminate */
+ return string;
+ }
+ /* non-0 exponent */
+
+ e=0; /* assume no E */
+ pre=(Int)(c-cstart)+exp; /* length+exp [c->LSD+1] */
+ /* [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 '.' */
+ if (e!=0) { /* engineering: may need to adjust */
+ Int adj; /* adjustment */
+ /* The C remainder operator is undefined for negative numbers, so */
+ /* a positive remainder calculation must be used here */
+ if (e<0) {
+ adj=(-e)%3;
+ if (adj!=0) adj=3-adj;
+ }
+ else { /* e>0 */
+ adj=e%3;
+ }
+ e=e-adj;
+ /* if dealing with zero still produce an exponent which is a */
+ /* multiple of three, as expected, but there will only be the */
+ /* one zero before the E, still. Otherwise note the padding. */
+ if (!DFISZERO(df)) pre+=adj;
+ else { /* is zero */
+ if (adj!=0) { /* 0.00Esnn needed */
+ e=e+3;
+ pre=-(2-adj);
+ }
+ } /* zero */
+ } /* engineering adjustment */
+ } /* exponential form */
+ /* printf("e=%ld pre=%ld exp=%ld\n", (LI)e, (LI)pre, (LI)exp); */
+
+ /* modify the coefficient, adding 0s, '.', and E+nn as needed */
+ if (pre>0) { /* ddd.ddd (plain), perhaps with E */
+ /* or dd00 padding for engineering */
+ char *dotat=cstart+pre;
+ if (dotat<c) { /* if embedded dot needed... */
+ /* move by fours; there must be space for junk at the end */
+ /* because there is still space for exponent */
+ s=dotat+ROUNDDOWN4(c-dotat); /* source */
+ t=s+1; /* target */
+ /* open the gap */
+ for (; s>=dotat; s-=4, t-=4) UINTAT(t)=UINTAT(s);
+ *dotat='.';
+ c++; /* length increased by one */
+ } /* need dot? */
+ else for (; c<dotat; c++) *c='0'; /* pad for engineering */
+ } /* pre>0 */
+ else {
+ /* -5<=pre<=0: here for plain 0.ddd or 0.000ddd forms (may have
+ E, but only for 0.00E+3 kind of case -- with plenty of spare
+ space in this case */
+ pre=-pre+2; /* gap width, including "0." */
+ t=cstart+ROUNDDOWN4(c-cstart)+pre; /* preferred first target point */
+ /* backoff if too far to the right */
+ if (t>string+DECSTRING-5) t=string+DECSTRING-5; /* adjust to fit */
+ /* now shift the entire coefficient to the right, being careful not */
+ /* to access to the left of string */
+ for (s=t-pre; s>=string; s-=4, t-=4) UINTAT(t)=UINTAT(s);
+ /* for Quads and Singles there may be a character or two left... */
+ s+=3; /* where next would come from */
+ for(; s>=cstart; s--, t--) *(t+3)=*(s);
+ /* now have fill 0. through 0.00000; use overlaps to avoid tests */
+ if (pre>=4) {
+ UINTAT(cstart+pre-4)=UINTAT("0000");
+ UINTAT(cstart)=UINTAT("0.00");
+ }
+ else { /* 2 or 3 */
+ *(cstart+pre-1)='0';
+ USHORTAT(cstart)=USHORTAT("0.");
+ }
+ c+=pre; /* to end */
+ }
+
+ /* finally add the E-part, if needed; it will never be 0, and has */
+ /* a maximum length of 3 or 4 digits (asserted above) */
+ if (e!=0) {
+ USHORTAT(c)=USHORTAT("E+"); /* starts with E, assume + */
+ c++;
+ if (e<0) {
+ *c='-'; /* oops, need '-' */
+ e=-e; /* uInt, please */
+ }
+ c++;
+ /* Three-character exponents are easy; 4-character a little trickier */
+ #if DECEMAXD<=3
+ u=&BIN2BCD8[e*4]; /* -> 3 digits + length byte */
+ /* copy fixed 4 characters [is safe], starting at non-zero */
+ /* and with character mask to convert BCD to char */
+ UINTAT(c)=UINTAT(u+3-*(u+3))|CHARMASK;
+ c+=*(u+3); /* bump pointer appropriately */
+ #elif DECEMAXD==4
+ if (e<1000) { /* 3 (or fewer) digits case */
+ u=&BIN2BCD8[e*4]; /* -> 3 digits + length byte */
+ UINTAT(c)=UINTAT(u+3-*(u+3))|CHARMASK; /* [as above] */
+ c+=*(u+3); /* bump pointer appropriately */
+ }
+ else { /* 4-digits */
+ Int thou=((e>>3)*1049)>>17; /* e/1000 */
+ Int rem=e-(1000*thou); /* e%1000 */
+ *c++=(char)('0'+(char)thou); /* the thousands digit */
+ u=&BIN2BCD8[rem*4]; /* -> 3 digits + length byte */
+ UINTAT(c)=UINTAT(u)|CHARMASK; /* copy fixed 3+1 characters [is safe] */
+ c+=3; /* bump pointer, always 3 digits */
+ }
+ #endif
+ }
+ *c='\0'; /* terminate */
+ /*printf("res %s\n", string); */
+ return string;
+ } /* decFloatToEngString */
+
+/* ------------------------------------------------------------------ */
+/* decFloatToPacked -- convert decFloat to Packed decimal + exponent */
+/* */
+/* df is the source decFloat */
+/* exp will be set to the unbiased exponent, q, or to a special */
+/* value in the form returned by decFloatGetExponent */
+/* packed is where DECPMAX nibbles will be written with the sign as */
+/* final nibble (0x0c for +, 0x0d for -); a NaN has a first nibble */
+/* of zero, and an infinity is all zeros. decDouble and decQuad */
+/* have a additional leading zero nibble, leading to result */
+/* lengths of 4, 9, and 18 bytes. */
+/* returns the sign of the coefficient (DECFLOAT_Sign if negative, */
+/* 0 otherwise) */
+/* */
+/* No error is possible, and no status will be set. */
+/* ------------------------------------------------------------------ */
+Int decFloatToPacked(const decFloat *df, Int *exp, uByte *packed) {
+ uByte bcdar[DECPMAX+2]; /* work buffer */
+ uByte *ip=bcdar, *op=packed; /* work pointers */
+ if (DFISINF(df)) {
+ memset(bcdar, 0, DECPMAX+2);
+ *exp=DECFLOAT_Inf;
+ }
+ else {
+ GETCOEFF(df, bcdar+1); /* use macro */
+ if (DFISNAN(df)) {
+ bcdar[1]=0; /* MSD needs clearing */
+ *exp=DFWORD(df, 0)&0x7e000000;
+ }
+ else { /* finite */
+ *exp=GETEXPUN(df);
+ }
+ }
+ /* now pack; coefficient currently at bcdar+1 */
+ #if SINGLE
+ ip++; /* ignore first byte */
+ #else
+ *ip=0; /* need leading zero */
+ #endif
+ /* set final byte to Packed BCD sign value */
+ bcdar[DECPMAX+1]=(DFISSIGNED(df) ? DECPMINUS : DECPPLUS);
+ /* pack an even number of bytes... */
+ for (; op<packed+((DECPMAX+2)/2); op++, ip+=2) {
+ *op=(uByte)((*ip<<4)+*(ip+1));
+ }
+ return (bcdar[DECPMAX+1]==DECPMINUS ? DECFLOAT_Sign : 0);
+ } /* decFloatToPacked */
+
+/* ------------------------------------------------------------------ */
+/* decFloatToString -- conversion to numeric string */
+/* */
+/* df is the decFloat format number to convert */
+/* string is the string where the result will be laid out */
+/* */
+/* string must be at least DECPMAX+9 characters (the worst case is */
+/* "-0.00000nnn...nnn\0", which is as long as the exponent form when */
+/* DECEMAXD<=4); this condition is asserted above */
+/* */
+/* No error is possible, and no status will be set */
+/* ------------------------------------------------------------------ */
+char * decFloatToString(const decFloat *df, 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 */
+ char *s, *t; /* .. (source, target) */
+ Int pre, e; /* work */
+ const uByte *u; /* .. */
+
+ /* Source words; macro handles endianness */
+ uInt sourhi=DFWORD(df, 0); /* word with sign */
+ #if DECPMAX==16
+ uInt sourlo=DFWORD(df, 1);
+ #elif DECPMAX==34
+ uInt sourmh=DFWORD(df, 1);
+ uInt sourml=DFWORD(df, 2);
+ uInt sourlo=DFWORD(df, 3);
+ #endif
+
+ c=string; /* where result will go */
+ if (((Int)sourhi)<0) *c++='-'; /* handle sign */
+ comb=sourhi>>26; /* sign+combination field */
+ msd=DECCOMBMSD[comb]; /* decode the combination field */
+ exp=DECCOMBEXP[comb]; /* .. */
+
+ if (EXPISSPECIAL(exp)) { /* special */
+ if (exp==DECFLOAT_Inf) { /* infinity */
+ strcpy(c, "Infinity");
+ return string; /* easy */
+ }
+ if (sourhi&0x02000000) *c++='s'; /* sNaN */
+ strcpy(c, "NaN"); /* complete word */
+ c+=3; /* step past */
+ /* quick exit if the payload is zero */
+ #if DECPMAX==7
+ if ((sourhi&0x000fffff)==0) return string;
+ #elif DECPMAX==16
+ if (sourlo==0 && (sourhi&0x0003ffff)==0) return string;
+ #elif DECPMAX==34
+ if (sourlo==0 && sourml==0 && sourmh==0
+ && (sourhi&0x00003fff)==0) return string;
+ #endif
+ /* otherwise drop through to add integer; set correct exp etc. */
+ exp=0; msd=0; /* setup for following code */
+ }
+ else { /* complete exponent; top two bits are in place */
+ exp+=GETECON(df)-DECBIAS; /* .. + continuation and unbias */
+ }
+
+ /* convert the digits of the significand to characters */
+ cstart=c; /* save start of coefficient */
+ if (msd) *c++=(char)('0'+(char)msd); /* non-zero most significant digit */
+
+ /* Decode the declets. After extracting each declet, it is */
+ /* decoded to a 4-uByte sequence by table lookup; the four uBytes */
+ /* are the three encoded BCD8 digits followed by a 1-byte length */
+ /* (significant digits, except that 000 has length 0). This allows */
+ /* us to left-align the first declet with non-zero content, then */
+ /* the remaining ones are full 3-char length. Fixed-length copies */
+ /* are used because variable-length memcpy causes a subroutine call */
+ /* in at least two compilers. (The copies are length 4 for speed */
+ /* and are safe because the last item in the array is of length */
+ /* three and has the length byte following.) */
+ #define dpd2char(dpdin) u=&DPD2BCD8[((dpdin)&0x3ff)*4]; \
+ if (c!=cstart) {UINTAT(c)=UINTAT(u)|CHARMASK; c+=3;} \
+ else if (*(u+3)) { \
+ UINTAT(c)=UINTAT(u+3-*(u+3))|CHARMASK; c+=*(u+3);}
+
+ #if DECPMAX==7
+ dpd2char(sourhi>>10); /* declet 1 */
+ dpd2char(sourhi); /* declet 2 */
+
+ #elif DECPMAX==16
+ dpd2char(sourhi>>8); /* declet 1 */
+ dpd2char((sourhi<<2) | (sourlo>>30)); /* declet 2 */
+ dpd2char(sourlo>>20); /* declet 3 */
+ dpd2char(sourlo>>10); /* declet 4 */
+ dpd2char(sourlo); /* declet 5 */
+
+ #elif DECPMAX==34
+ dpd2char(sourhi>>4); /* declet 1 */
+ dpd2char((sourhi<<6) | (sourmh>>26)); /* declet 2 */
+ dpd2char(sourmh>>16); /* declet 3 */
+ dpd2char(sourmh>>6); /* declet 4 */
+ dpd2char((sourmh<<4) | (sourml>>28)); /* declet 5 */
+ dpd2char(sourml>>18); /* declet 6 */
+ dpd2char(sourml>>8); /* declet 7 */
+ dpd2char((sourml<<2) | (sourlo>>30)); /* declet 8 */
+ dpd2char(sourlo>>20); /* declet 9 */
+ dpd2char(sourlo>>10); /* declet 10 */
+ dpd2char(sourlo); /* declet 11 */
+ #endif
+
+ if (c==cstart) *c++='0'; /* all zeros, empty -- make "0" */
+
+ /*[This fast path is valid but adds 3-5 cycles to worst case length] */
+ /*if (exp==0) { // integer or NaN case -- easy */
+ /* *c='\0'; // terminate */
+ /* return string; */
+ /* } */
+
+ e=0; /* assume no E */
+ pre=(Int)(c-cstart)+exp; /* length+exp [c->LSD+1] */
+ /* [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 */
+ if (pre>0) { /* ddd.ddd (plain), perhaps with E */
+ char *dotat=cstart+pre;
+ if (dotat<c) { /* if embedded dot needed... */
+ /* move by fours; there must be space for junk at the end */
+ /* because there is still space for exponent */
+ s=dotat+ROUNDDOWN4(c-dotat); /* source */
+ t=s+1; /* target */
+ /* open the gap */
+ for (; s>=dotat; s-=4, t-=4) UINTAT(t)=UINTAT(s);
+ *dotat='.';
+ c++; /* length increased by one */
+ } /* need dot? */
+
+ /* finally add the E-part, if needed; it will never be 0, and has */
+ /* a maximum length of 3 or 4 digits (asserted above) */
+ if (e!=0) {
+ USHORTAT(c)=USHORTAT("E+"); /* starts with E, assume + */
+ c++;
+ if (e<0) {
+ *c='-'; /* oops, need '-' */
+ e=-e; /* uInt, please */
+ }
+ c++;
+ /* Three-character exponents are easy; 4-character a little trickier */
+ #if DECEMAXD<=3
+ u=&BIN2BCD8[e*4]; /* -> 3 digits + length byte */
+ /* copy fixed 4 characters [is safe], starting at non-zero */
+ /* and with character mask to convert BCD to char */
+ UINTAT(c)=UINTAT(u+3-*(u+3))|CHARMASK;
+ c+=*(u+3); /* bump pointer appropriately */
+ #elif DECEMAXD==4
+ if (e<1000) { /* 3 (or fewer) digits case */
+ u=&BIN2BCD8[e*4]; /* -> 3 digits + length byte */
+ UINTAT(c)=UINTAT(u+3-*(u+3))|CHARMASK; /* [as above] */
+ c+=*(u+3); /* bump pointer appropriately */
+ }
+ else { /* 4-digits */
+ Int thou=((e>>3)*1049)>>17; /* e/1000 */
+ Int rem=e-(1000*thou); /* e%1000 */
+ *c++=(char)('0'+(char)thou); /* the thousands digit */
+ u=&BIN2BCD8[rem*4]; /* -> 3 digits + length byte */
+ UINTAT(c)=UINTAT(u)|CHARMASK; /* copy fixed 3+1 characters [is safe] */
+ c+=3; /* bump pointer, always 3 digits */
+ }
+ #endif
+ }
+ *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) */
+ /* Surprisingly, this is close to being the worst-case path, so the */
+ /* shift is done by fours; this is a little tricky because the */
+ /* rightmost character to be written must not be beyond where the */
+ /* rightmost terminator could be -- so backoff to not touch */
+ /* terminator position if need be (this can make exact alignments */
+ /* for full Doubles, but in some cases needs care not to access too */
+ /* far to the left) */
+
+ pre=-pre+2; /* gap width, including "0." */
+ t=cstart+ROUNDDOWN4(c-cstart)+pre; /* preferred first target point */
+ /* backoff if too far to the right */
+ if (t>string+DECSTRING-5) t=string+DECSTRING-5; /* adjust to fit */
+ /* now shift the entire coefficient to the right, being careful not */
+ /* to access to the left of string */
+ for (s=t-pre; s>=string; s-=4, t-=4) UINTAT(t)=UINTAT(s);
+ /* for Quads and Singles there may be a character or two left... */
+ s+=3; /* where next would come from */
+ for(; s>=cstart; s--, t--) *(t+3)=*(s);
+ /* now have fill 0. through 0.00000; use overlaps to avoid tests */
+ if (pre>=4) {
+ UINTAT(cstart+pre-4)=UINTAT("0000");
+ UINTAT(cstart)=UINTAT("0.00");
+ }
+ else { /* 2 or 3 */
+ *(cstart+pre-1)='0';
+ USHORTAT(cstart)=USHORTAT("0.");
+ }
+ *(c+pre)='\0'; /* terminate */
+ return string;
+ } /* decFloatToString */
+
+/* ------------------------------------------------------------------ */
+/* decFloatToWider -- conversion to next-wider format */
+/* */
+/* source is the decFloat format number which gets the result of */
+/* the conversion */
+/* wider is the decFloatWider format number which will be narrowed */
+/* returns wider */
+/* */
+/* Widening is always exact; no status is set (sNaNs are copied and */
+/* do not signal). The result will be canonical if the source is, */
+/* and may or may not be if the source is not. */
+/* ------------------------------------------------------------------ */
+/* widening is not possible for decQuad format numbers; simply omit */
+#if !QUAD
+decFloatWider * decFloatToWider(const decFloat *source, decFloatWider *wider) {
+ uInt msd;
+
+ /* Construct and copy the sign word */
+ if (DFISSPECIAL(source)) {
+ /* copy sign, combination, and first bit of exponent (sNaN selector) */
+ DFWWORD(wider, 0)=DFWORD(source, 0)&0xfe000000;
+ msd=0;
+ }
+ else { /* is finite number */
+ uInt exp=GETEXPUN(source)+DECWBIAS; /* get unbiased exponent and rebias */
+ uInt code=(exp>>DECWECONL)<<29; /* set two bits of exp [msd=0] */
+ code|=(exp<<(32-6-DECWECONL)) & 0x03ffffff; /* add exponent continuation */
+ code|=DFWORD(source, 0)&0x80000000; /* add sign */
+ DFWWORD(wider, 0)=code; /* .. and place top word in wider */
+ msd=GETMSD(source); /* get source coefficient MSD [0-9] */
+ }
+ /* Copy the coefficient and clear any 'unused' words to left */
+ #if SINGLE
+ DFWWORD(wider, 1)=(DFWORD(source, 0)&0x000fffff)|(msd<<20);
+ #elif DOUBLE
+ DFWWORD(wider, 2)=(DFWORD(source, 0)&0x0003ffff)|(msd<<18);
+ DFWWORD(wider, 3)=DFWORD(source, 1);
+ DFWWORD(wider, 1)=0;
+ #endif
+ return wider;
+ } /* decFloatToWider */
+#endif
+
+/* ------------------------------------------------------------------ */
+/* decFloatVersion -- return package version string */
+/* */
+/* returns a constant string describing this package */
+/* ------------------------------------------------------------------ */
+const char *decFloatVersion(void) {
+ return DECVERSION;
+ } /* decFloatVersion */
+
+/* ------------------------------------------------------------------ */
+/* decFloatZero -- set to canonical (integer) zero */
+/* */
+/* df is the decFloat format number to integer +0 (q=0, c=+0) */
+/* returns df */
+/* */
+/* No error is possible, and no status can be set. */
+/* ------------------------------------------------------------------ */
+decFloat * decFloatZero(decFloat *df){
+ DFWORD(df, 0)=ZEROWORD; /* set appropriate top word */
+ #if DOUBLE || QUAD
+ DFWORD(df, 1)=0;
+ #if QUAD
+ DFWORD(df, 2)=0;
+ DFWORD(df, 3)=0;
+ #endif
+ #endif
+ /* decFloatShow(df, "zero"); */
+ return df;
+ } /* decFloatZero */
+
+/* ------------------------------------------------------------------ */
+/* Private generic function (not format-specific) for development use */
+/* ------------------------------------------------------------------ */
+/* This is included once only, for all to use */
+#if QUAD && (DECCHECK || DECTRACE)
+ /* ---------------------------------------------------------------- */
+ /* decShowNum -- display bcd8 number in debug form */
+ /* */
+ /* num is the bcdnum to display */
+ /* tag is a string to label the display */
+ /* ---------------------------------------------------------------- */
+ void decShowNum(const bcdnum *num, const char *tag) {
+ const char *csign="+"; /* sign character */
+ uByte *ub; /* work */
+ if (num->sign==DECFLOAT_Sign) csign="-";
+
+ printf(">%s> ", tag);
+ if (num->exponent==DECFLOAT_Inf) printf("%sInfinity", csign);
+ else if (num->exponent==DECFLOAT_qNaN) printf("%sqNaN", csign);
+ else if (num->exponent==DECFLOAT_sNaN) printf("%ssNaN", csign);
+ else { /* finite */
+ char qbuf[10]; /* for right-aligned q */
+ char *c; /* work */
+ const uByte *u; /* .. */
+ Int e=num->exponent; /* .. exponent */
+ strcpy(qbuf, "q=");
+ c=&qbuf[2]; /* where exponent will go */
+ /* lay out the exponent */
+ if (e<0) {
+ *c++='-'; /* add '-' */
+ e=-e; /* uInt, please */
+ }
+ #if DECEMAXD>4
+ #error Exponent form is too long for ShowNum to lay out
+ #endif
+ if (e==0) *c++='0'; /* 0-length case */
+ else if (e<1000) { /* 3 (or fewer) digits case */
+ u=&BIN2BCD8[e*4]; /* -> 3 digits + length byte */
+ UINTAT(c)=UINTAT(u+3-*(u+3))|CHARMASK; /* [as above] */
+ c+=*(u+3); /* bump pointer appropriately */
+ }
+ else { /* 4-digits */
+ Int thou=((e>>3)*1049)>>17; /* e/1000 */
+ Int rem=e-(1000*thou); /* e%1000 */
+ *c++=(char)('0'+(char)thou); /* the thousands digit */
+ u=&BIN2BCD8[rem*4]; /* -> 3 digits + length byte */
+ UINTAT(c)=UINTAT(u)|CHARMASK; /* copy fixed 3+1 characters [is safe] */
+ c+=3; /* bump pointer, always 3 digits */
+ }
+ *c='\0'; /* add terminator */
+ printf("%7s c=%s", qbuf, csign);
+ }
+
+ if (!EXPISSPECIAL(num->exponent) || num->msd!=num->lsd || *num->lsd!=0) {
+ for (ub=num->msd; ub<=num->lsd; ub++) { /* coefficient... */
+ printf("%1x", *ub);
+ if ((num->lsd-ub)%3==0 && ub!=num->lsd) printf(" "); /* 4-space */
+ }
+ }
+ printf("\n");
+ } /* decShowNum */
+#endif
projects / msp430-gcc.git / blobdiff