-/* Decimal 64-bit format module for the decNumber C Library
- Copyright (C) 2005 Free Software Foundation, Inc.
+/* 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.
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. */
-/* */
-/* No arithmetic routines are included; decNumber provides these. */
-/* */
-/* Error handling is the same as decNumber (qv.). */
+/* 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 <string.h> /* [for memset/memcpy] */
-#include <stdio.h> /* [for printf] */
+#include <string.h> /* [for memset/memcpy] */
+#include <stdio.h> /* [for printf] */
+
+#include "dconfig.h" /* GCC definitions */
+#define DECNUMDIGITS 16 /* make decNumbers with space for 16 */
+#include "decNumber.h" /* base number library */
+#include "decNumberLocal.h" /* decNumber local types, etc. */
+#include "decimal64.h" /* our primary include */
-#define DECNUMDIGITS 16 /* we need decNumbers with space for 16 */
-#include "config.h"
-#include "decNumber.h" /* base number library */
-#include "decNumberLocal.h" /* decNumber local types, etc. */
-#include "decimal64.h" /* our primary include */
-#include "decUtility.h" /* utility routines */
+/* Utility routines and tables [in decimal64.c]; externs for C++ */
+extern const uInt COMBEXP[32], COMBMSD[32];
+extern const uShort DPD2BIN[1024];
+extern const uShort BIN2DPD[1000];
+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 */
-void decNumberShow (const decNumber *); /* .. */
+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 "decDPD.h" /* lookup tables */
+
/* ------------------------------------------------------------------ */
-/* 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 */
-/* */
+/* 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. */
-/* */
+/* 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 pad = 0; /* coefficient pad digits */
- decNumber dw; /* work */
- decContext dc; /* .. */
- uByte isneg = dn->bits & DECNEG; /* non-0 if original sign set */
- uInt comb, exp; /* work */
-
- /* If the number is finite, and has too many digits, or the exponent */
- /* could be out of range then we reduce the number under the */
- /* appropriate constraints */
- if (!(dn->bits & DECSPECIAL))
- { /* not a special value */
- Int ae = dn->exponent + dn->digits - 1; /* adjusted exponent */
- 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, but it will be restored below] */
- status |= dc.status; /* save status */
- dn = &dw; /* use the work number */
- }
- /* [this could have pushed number to Infinity or zero, so this */
- /* rounding must be done before we generate the decimal64] */
- }
+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 */
- DEC_clear (d64); /* clean the target */
- if (dn->bits & DECSPECIAL)
- { /* a special value */
- uByte top; /* work */
- if (dn->bits & DECINF)
- top = DECIMAL_Inf;
- else
- { /* sNaN or qNaN */
- if ((*dn->lsu != 0 || dn->digits > 1) /* non-zero coefficient */
- && (dn->digits < DECIMAL64_Pmax))
- { /* coefficient fits */
- decDensePackCoeff (dn, d64->bytes, sizeof (d64->bytes), 0);
- }
- if (dn->bits & DECNAN)
- top = DECIMAL_NaN;
- else
- top = DECIMAL_sNaN;
+ 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);
}
- d64->bytes[0] = top;
- }
- else if (decNumberIsZero (dn))
- { /* a zero */
+ 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;
- status |= DEC_Clamped;
+ 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;
- }
+ else {
+ exp=dn->exponent+DECIMAL64_Bias; /* bias exponent */
+ if (exp>DECIMAL64_Ehigh) { /* top clamp */
+ exp=DECIMAL64_Ehigh;
+ status|=DEC_Clamped;
+ }
}
- comb = (exp >> 5) & 0x18; /* combination field */
- d64->bytes[0] = (uByte) (comb << 2);
- exp &= 0xff; /* remaining exponent bits */
- decimal64SetExpCon (d64, exp);
- }
- else
- { /* non-zero finite number */
- uInt msd; /* work */
-
- /* we have a dn that fits, 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;
+ 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;
}
- decDensePackCoeff (dn, d64->bytes, sizeof (d64->bytes), pad);
+ /* 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;
+ }
- /* save and clear the top digit */
- msd = ((unsigned) d64->bytes[1] >> 2) & 0x0f;
- d64->bytes[1] &= 0x03;
/* create the combination field */
- if (msd >= 8)
- comb = 0x18 | (msd & 0x01) | ((exp >> 7) & 0x06);
- else
- comb = (msd & 0x07) | ((exp >> 5) & 0x18);
- d64->bytes[0] = (uByte) (comb << 2);
- exp &= 0xff; /* remaining exponent bits */
- decimal64SetExpCon (d64, exp);
- }
+ 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 */
- if (isneg)
- decimal64SetSign (d64, 1);
- if (status != 0)
- decContextSetStatus (set, status); /* pass on status */
+ /* 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 */
+ }
- /*decimal64Show(d64); */
+ 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. */
+/* 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 */
- decimal64 wk; /* working copy, if needed */
- uInt top = d64->bytes[0] & 0x7f; /* top byte, less sign bit */
- decNumberZero (dn); /* clean target */
- /* set the sign if negative */
- if (decimal64Sign (d64))
- dn->bits = DECNEG;
-
- if (top >= 0x78)
- { /* is a special */
- if ((top & 0x7c) == (DECIMAL_Inf & 0x7c))
- dn->bits |= DECINF;
- else if ((top & 0x7e) == (DECIMAL_NaN & 0x7e))
- dn->bits |= DECNAN;
- else
- dn->bits |= DECSNAN;
- msd = 0; /* no top digit */
+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
- { /* have a finite number */
- uInt comb = top >> 2; /* combination field */
- uInt exp; /* exponent */
-
- if (comb >= 0x18)
- {
- msd = 8 + (comb & 0x01);
- exp = (comb & 0x06) << 7; /* MSBs */
- }
- else
- {
- msd = comb & 0x07;
- exp = (comb & 0x18) << 5;
- }
- dn->exponent = exp + decimal64ExpCon (d64) - DECIMAL64_Bias; /* remove bias */
+ else {
+ sourhi=pu[0]; /* directly load the high int */
+ sourlo=pu[1]; /* then the low int */
}
- /* get the coefficient, unless infinite */
- if (!(dn->bits & DECINF))
- {
- Int bunches = DECIMAL64_Pmax / 3; /* coefficient full bunches to convert */
- Int odd = 0; /* assume MSD is 0 (no odd bunch) */
- if (msd != 0)
- { /* coefficient has leading non-0 digit */
- /* make a copy of the decimal64, with an extra bunch which has */
- /* the top digit ready for conversion */
- wk = *d64; /* take a copy */
- wk.bytes[0] = 0; /* clear all but coecon */
- wk.bytes[1] &= 0x03; /* .. */
- wk.bytes[1] |= (msd << 2); /* and prefix MSD */
- odd++; /* indicate the extra */
- d64 = &wk; /* use the work copy */
- }
- decDenseUnpackCoeff (d64->bytes, sizeof (d64->bytes), dn, bunches, odd);
+ 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. */
+/* 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 *
-decimal64ToString (const decimal64 * d64, char *string)
-{
- decNumber dn; /* work */
- decimal64ToNumber (d64, &dn);
- decNumberToString (&dn, string);
+char * decimal64ToEngString(const decimal64 *d64, char *string){
+ decNumber dn; /* work */
+ decimal64ToNumber(d64, &dn);
+ decNumberToEngString(&dn, string);
return string;
-}
-
-char *
-decimal64ToEngString (const decimal64 * d64, char *string)
-{
- decNumber dn; /* work */
- decimal64ToNumber (d64, &dn);
- decNumberToEngString (&dn, 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); */
-/* */
+/* to-number -- conversion from numeric string */
+/* */
+/* decimal64FromString(result, string, set); */
+/* */
/* result is the decimal64 format number which gets the result of */
-/* the conversion */
+/* the conversion */
/* *string is the character string which should contain a valid */
-/* number (which may be a special value) */
-/* set is the context */
-/* */
+/* 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; /* .. */
+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 */
+ decContextDefault(&dc, DEC_INIT_DECIMAL64); /* no traps, please */
+ dc.round=set->round; /* use supplied rounding */
- decNumberFromString (&dn, string, &dc); /* will round if needed */
+ 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 */
+ 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 single in hexadecimal [debug aid] */
-/* d64 -- the number to show */
+/* 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;
- j = 0;
- for (i = 0; i < DECIMAL64_Bytes; i++)
- {
- sprintf (&buf[j], "%02x", d64->bytes[i]);
- j = j + 2;
+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));
}
- printf (" D64> %s [S:%d Cb:%02x E:%d]\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 "decDPD.h" /* lookup tables */
+
+/* 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 */
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