diff libdecnumber/dpd/decimal128.c @ 0:a06113de4d67

first commit
author kent <kent@cr.ie.u-ryukyu.ac.jp>
date Fri, 17 Jul 2009 14:47:48 +0900
parents
children 77e2b8dfacca
line wrap: on
line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libdecnumber/dpd/decimal128.c	Fri Jul 17 14:47:48 2009 +0900
@@ -0,0 +1,561 @@
+/* Decimal 128-bit format module for the decNumber C Library.
+   Copyright (C) 2005, 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/>.  */
+
+/* ------------------------------------------------------------------ */
+/* Decimal 128-bit format module				      */
+/* ------------------------------------------------------------------ */
+/* This module comprises the routines for decimal128 format numbers.  */
+/* Conversions are supplied to and from decNumber and String.	      */
+/*								      */
+/* This is used when decNumber provides operations, either for all    */
+/* operations or as a proxy between decNumber and decSingle.	      */
+/*								      */
+/* Error handling is the same as decNumber (qv.).		      */
+/* ------------------------------------------------------------------ */
+#include <string.h>	      /* [for memset/memcpy] */
+#include <stdio.h>	      /* [for printf] */
+
+#include "dconfig.h"	      /* GCC definitions */
+#define	 DECNUMDIGITS 34      /* make decNumbers with space for 34 */
+#include "decNumber.h"	      /* base number library */
+#include "decNumberLocal.h"   /* decNumber local types, etc. */
+#include "decimal128.h"	      /* our primary include */
+
+/* Utility routines and tables [in decimal64.c] */
+extern const uInt   COMBEXP[32], COMBMSD[32];
+extern const uShort DPD2BIN[1024];
+extern const uShort BIN2DPD[1000];	/* [not used] */
+extern const uByte  BIN2CHAR[4001];
+
+extern void decDigitsFromDPD(decNumber *, const uInt *, Int);
+extern void decDigitsToDPD(const decNumber *, uInt *, Int);
+
+#if DECTRACE || DECCHECK
+void decimal128Show(const decimal128 *);	  /* 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))
+
+/* ------------------------------------------------------------------ */
+/* decimal128FromNumber -- convert decNumber to decimal128	      */
+/*								      */
+/*   ds is the target decimal128				      */
+/*   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 DECIMAL128_Pmax*/
+/* digits or an overflow is detected).	If the exponent is out of the */
+/* valid range then Overflow or Underflow will be raised.	      */
+/* After Underflow a subnormal result is possible.		      */
+/*								      */
+/* DEC_Clamped is set if the number has to be 'folded down' to fit,   */
+/* by reducing its exponent and multiplying the coefficient by a      */
+/* power of ten, or if the exponent on a zero had to be clamped.      */
+/* ------------------------------------------------------------------ */
+decimal128 * decimal128FromNumber(decimal128 *d128, 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[4]={0,0,0,0};	   /* target 128-bit */
+  #define targhi targar[3]	   /* name the word with the sign */
+  #define targmh targar[2]	   /* name the words */
+  #define targml targar[1]	   /* .. */
+  #define targlo targar[0]	   /* .. */
+
+  /* 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 */
+  /* decimal128] */
+  ae=dn->exponent+dn->digits-1;		     /* [0 if special] */
+  if (dn->digits>DECIMAL128_Pmax	     /* too many digits */
+   || ae>DECIMAL128_Emax		     /* likely overflow */
+   || ae<DECIMAL128_Emin) {		     /* likely underflow */
+    decContextDefault(&dc, DEC_INIT_DECIMAL128); /* [no traps] */
+    dc.round=set->round;		     /* use supplied rounding */
+    decNumberPlus(&dw, dn, &dc);	     /* (round and check) */
+    /* [this changes -0 to 0, so enforce the sign...] */
+    dw.bits|=dn->bits&DECNEG;
+    status=dc.status;			     /* save status */
+    dn=&dw;				     /* use the work number */
+    } /* maybe out of range */
+
+  if (dn->bits&DECSPECIAL) {			  /* a special value */
+    if (dn->bits&DECINF) targhi=DECIMAL_Inf<<24;
+     else {					  /* sNaN or qNaN */
+      if ((*dn->lsu!=0 || dn->digits>1)		  /* non-zero coefficient */
+       && (dn->digits<DECIMAL128_Pmax)) {	  /* coefficient fits */
+	decDigitsToDPD(dn, targar, 0);
+	}
+      if (dn->bits&DECNAN) targhi|=DECIMAL_NaN<<24;
+       else targhi|=DECIMAL_sNaN<<24;
+      } /* a NaN */
+    } /* special */
+
+   else { /* is finite */
+    if (decNumberIsZero(dn)) {		     /* is a zero */
+      /* set and clamp exponent */
+      if (dn->exponent<-DECIMAL128_Bias) {
+	exp=0;				     /* low clamp */
+	status|=DEC_Clamped;
+	}
+       else {
+	exp=dn->exponent+DECIMAL128_Bias;    /* bias exponent */
+	if (exp>DECIMAL128_Ehigh) {	     /* top clamp */
+	  exp=DECIMAL128_Ehigh;
+	  status|=DEC_Clamped;
+	  }
+	}
+      comb=(exp>>9) & 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+DECIMAL128_Bias);	   /* bias exponent */
+      if (exp>DECIMAL128_Ehigh) {		   /* fold-down case */
+	pad=exp-DECIMAL128_Ehigh;
+	exp=DECIMAL128_Ehigh;			   /* [to maximum] */
+	status|=DEC_Clamped;
+	}
+
+      /* [fastpath for common case is not a win, here] */
+      decDigitsToDPD(dn, targar, pad);
+      /* save and clear the top digit */
+      msd=targhi>>14;
+      targhi&=0x00003fff;
+
+      /* create the combination field */
+      if (msd>=8) comb=0x18 | ((exp>>11) & 0x06) | (msd & 0x01);
+	     else comb=((exp>>9) & 0x18) | msd;
+      }
+    targhi|=comb<<26;		   /* add combination field .. */
+    targhi|=(exp&0xfff)<<14;	   /* .. and exponent continuation */
+    } /* finite */
+
+  if (dn->bits&DECNEG) targhi|=0x80000000; /* add sign bit */
+
+  /* now write to storage; this is endian */
+  pu=(uInt *)d128->bytes;	   /* overlay */
+  if (DECLITEND) {
+    pu[0]=targlo;		   /* directly store the low int */
+    pu[1]=targml;		   /* then the mid-low */
+    pu[2]=targmh;		   /* then the mid-high */
+    pu[3]=targhi;		   /* then the high int */
+    }
+   else {
+    pu[0]=targhi;		   /* directly store the high int */
+    pu[1]=targmh;		   /* then the mid-high */
+    pu[2]=targml;		   /* then the mid-low */
+    pu[3]=targlo;		   /* then the low int */
+    }
+
+  if (status!=0) decContextSetStatus(set, status); /* pass on status */
+  /* decimal128Show(d128); */
+  return d128;
+  } /* decimal128FromNumber */
+
+/* ------------------------------------------------------------------ */
+/* decimal128ToNumber -- convert decimal128 to decNumber	      */
+/*   d128 is the source decimal128				      */
+/*   dn is the target number, with appropriate space		      */
+/* No error is possible.					      */
+/* ------------------------------------------------------------------ */
+decNumber * decimal128ToNumber(const decimal128 *d128, decNumber *dn) {
+  uInt msd;			   /* coefficient MSD */
+  uInt exp;			   /* exponent top two bits */
+  uInt comb;			   /* combination field */
+  const uInt *pu;		   /* work */
+  Int  need;			   /* .. */
+  uInt sourar[4];		   /* source 128-bit */
+  #define sourhi sourar[3]	   /* name the word with the sign */
+  #define sourmh sourar[2]	   /* and the mid-high word */
+  #define sourml sourar[1]	   /* and the mod-low word */
+  #define sourlo sourar[0]	   /* and the lowest word */
+
+  /* load source from storage; this is endian */
+  pu=(const uInt *)d128->bytes;	   /* overlay */
+  if (DECLITEND) {
+    sourlo=pu[0];		   /* directly load the low int */
+    sourml=pu[1];		   /* then the mid-low */
+    sourmh=pu[2];		   /* then the mid-high */
+    sourhi=pu[3];		   /* then the high int */
+    }
+   else {
+    sourhi=pu[0];		   /* directly load the high int */
+    sourmh=pu[1];		   /* then the mid-high */
+    sourml=pu[2];		   /* then the mid-low */
+    sourlo=pu[3];		   /* then the low int */
+    }
+
+  comb=(sourhi>>26)&0x1f;	   /* combination field */
+
+  decNumberZero(dn);		   /* clean number */
+  if (sourhi&0x80000000) dn->bits=DECNEG; /* set sign if negative */
+
+  msd=COMBMSD[comb];		   /* decode the combination field */
+  exp=COMBEXP[comb];		   /* .. */
+
+  if (exp==3) {			   /* is a special */
+    if (msd==0) {
+      dn->bits|=DECINF;
+      return dn;		   /* no coefficient needed */
+      }
+    else if (sourhi&0x02000000) dn->bits|=DECSNAN;
+    else dn->bits|=DECNAN;
+    msd=0;			   /* no top digit */
+    }
+   else {			   /* is a finite number */
+    dn->exponent=(exp<<12)+((sourhi>>14)&0xfff)-DECIMAL128_Bias; /* unbiased */
+    }
+
+  /* get the coefficient */
+  sourhi&=0x00003fff;		   /* clean coefficient continuation */
+  if (msd) {			   /* non-zero msd */
+    sourhi|=msd<<14;		   /* prefix to coefficient */
+    need=12;			   /* process 12 declets */
+    }
+   else { /* msd=0 */
+    if (sourhi) need=11;	   /* declets to process */
+     else if (sourmh) need=10;
+     else if (sourml) need=7;
+     else if (sourlo) need=4;
+     else return dn;		   /* easy: coefficient is 0 */
+    } /*msd=0 */
+
+  decDigitsFromDPD(dn, sourar, need);	/* process declets */
+  /* decNumberShow(dn); */
+  return dn;
+  } /* decimal128ToNumber */
+
+/* ------------------------------------------------------------------ */
+/* to-scientific-string -- conversion to numeric string		      */
+/* to-engineering-string -- conversion to numeric string	      */
+/*								      */
+/*   decimal128ToString(d128, string);				      */
+/*   decimal128ToEngString(d128, string);			      */
+/*								      */
+/*  d128 is the decimal128 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 * decimal128ToEngString(const decimal128 *d128, char *string){
+  decNumber dn;				/* work */
+  decimal128ToNumber(d128, &dn);
+  decNumberToEngString(&dn, string);
+  return string;
+  } /* decimal128ToEngString */
+
+char * decimal128ToString(const decimal128 *d128, 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[4];		   /* source 128-bit */
+  #define sourhi sourar[3]	   /* name the word with the sign */
+  #define sourmh sourar[2]	   /* and the mid-high word */
+  #define sourml sourar[1]	   /* and the mod-low word */
+  #define sourlo sourar[0]	   /* and the lowest word */
+
+  /* load source from storage; this is endian */
+  pu=(const uInt *)d128->bytes;	   /* overlay */
+  if (DECLITEND) {
+    sourlo=pu[0];		   /* directly load the low int */
+    sourml=pu[1];		   /* then the mid-low */
+    sourmh=pu[2];		   /* then the mid-high */
+    sourhi=pu[3];		   /* then the high int */
+    }
+   else {
+    sourhi=pu[0];		   /* directly load the high int */
+    sourmh=pu[1];		   /* then the mid-high */
+    sourml=pu[2];		   /* then the mid-low */
+    sourlo=pu[3];		   /* 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 && sourml==0 && sourmh==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<<12)+((sourhi>>14)&0xfff)-DECIMAL128_Bias; /* unbiased */
+
+  /* convert 34 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>>4)&0x3ff;		     /* declet 1 */
+  dpd2char;
+  dpd=((sourhi&0xf)<<6) | (sourmh>>26);	     /* declet 2 */
+  dpd2char;
+  dpd=(sourmh>>16)&0x3ff;		     /* declet 3 */
+  dpd2char;
+  dpd=(sourmh>>6)&0x3ff;		     /* declet 4 */
+  dpd2char;
+  dpd=((sourmh&0x3f)<<4) | (sourml>>28);     /* declet 5 */
+  dpd2char;
+  dpd=(sourml>>18)&0x3ff;		     /* declet 6 */
+  dpd2char;
+  dpd=(sourml>>8)&0x3ff;		     /* declet 7 */
+  dpd2char;
+  dpd=((sourml&0xff)<<2) | (sourlo>>30);     /* declet 8 */
+  dpd2char;
+  dpd=(sourlo>>20)&0x3ff;		     /* declet 9 */
+  dpd2char;
+  dpd=(sourlo>>10)&0x3ff;		     /* declet 10 */
+  dpd2char;
+  dpd=(sourlo)&0x3ff;			     /* declet 11 */
+  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 4 digits */
+    if (e!=0) {
+      *c++='E';			   /* starts with E */
+      *c++='+';			   /* assume positive */
+      if (e<0) {
+	*(c-1)='-';		   /* oops, need '-' */
+	e=-e;			   /* uInt, please */
+	}
+      if (e<1000) {		   /* 3 (or fewer) digits case */
+	u=&BIN2CHAR[e*4];	   /* -> length byte */
+	memcpy(c, u+4-*u, 4);	   /* copy fixed 4 characters [is safe] */
+	c+=*u;			   /* bump pointer appropriately */
+	}
+       else {			   /* 4-digits */
+	Int thou=((e>>3)*1049)>>17; /* e/1000 */
+	Int rem=e-(1000*thou);	    /* e%1000 */
+	*c++='0'+(char)thou;
+	u=&BIN2CHAR[rem*4];	   /* -> length byte */
+	memcpy(c, u+1, 4);	   /* copy fixed 3+1 characters [is safe] */
+	c+=3;			   /* bump pointer, always 3 digits */
+	}
+      }
+    *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;
+  } /* decimal128ToString */
+
+/* ------------------------------------------------------------------ */
+/* to-number -- conversion from numeric string			      */
+/*								      */
+/*   decimal128FromString(result, string, set);			      */
+/*								      */
+/*  result  is the decimal128 format number which gets the result of  */
+/*	    the conversion					      */
+/*  *string is the character string which should contain a valid      */
+/*	    number (which may be a special value)		      */
+/*  set	    is the context					      */
+/*								      */
+/* The context is supplied to this routine is used for error handling */
+/* (setting of status and traps) and for the rounding mode, only.     */
+/* If an error occurs, the result will be a valid decimal128 NaN.     */
+/* ------------------------------------------------------------------ */
+decimal128 * decimal128FromString(decimal128 *result, const char *string,
+				  decContext *set) {
+  decContext dc;			     /* work */
+  decNumber dn;				     /* .. */
+
+  decContextDefault(&dc, DEC_INIT_DECIMAL128); /* no traps, please */
+  dc.round=set->round;			       /* use supplied rounding */
+
+  decNumberFromString(&dn, string, &dc);     /* will round if needed */
+  decimal128FromNumber(result, &dn, &dc);
+  if (dc.status!=0) {			     /* something happened */
+    decContextSetStatus(set, dc.status);     /* .. pass it on */
+    }
+  return result;
+  } /* decimal128FromString */
+
+/* ------------------------------------------------------------------ */
+/* decimal128IsCanonical -- test whether encoding is canonical	      */
+/*   d128 is the source decimal128				      */
+/*   returns 1 if the encoding of d128 is canonical, 0 otherwise      */
+/* No error is possible.					      */
+/* ------------------------------------------------------------------ */
+uint32_t decimal128IsCanonical(const decimal128 *d128) {
+  decNumber dn;				/* work */
+  decimal128 canon;			 /* .. */
+  decContext dc;			/* .. */
+  decContextDefault(&dc, DEC_INIT_DECIMAL128);
+  decimal128ToNumber(d128, &dn);
+  decimal128FromNumber(&canon, &dn, &dc);/* canon will now be canonical */
+  return memcmp(d128, &canon, DECIMAL128_Bytes)==0;
+  } /* decimal128IsCanonical */
+
+/* ------------------------------------------------------------------ */
+/* decimal128Canonical -- copy an encoding, ensuring it is canonical  */
+/*   d128 is the source decimal128				      */
+/*   result is the target (may be the same decimal128)		      */
+/*   returns result						      */
+/* No error is possible.					      */
+/* ------------------------------------------------------------------ */
+decimal128 * decimal128Canonical(decimal128 *result, const decimal128 *d128) {
+  decNumber dn;				/* work */
+  decContext dc;			/* .. */
+  decContextDefault(&dc, DEC_INIT_DECIMAL128);
+  decimal128ToNumber(d128, &dn);
+  decimal128FromNumber(result, &dn, &dc);/* result will now be canonical */
+  return result;
+  } /* decimal128Canonical */
+
+#if DECTRACE || DECCHECK
+/* Macros for accessing decimal128 fields.  These assume the argument
+   is a reference (pointer) to the decimal128 structure, and the
+   decimal128 is in network byte order (big-endian) */
+/* Get sign */
+#define decimal128Sign(d)	((unsigned)(d)->bytes[0]>>7)
+
+/* Get combination field */
+#define decimal128Comb(d)	(((d)->bytes[0] & 0x7c)>>2)
+
+/* Get exponent continuation [does not remove bias] */
+#define decimal128ExpCon(d)	((((d)->bytes[0] & 0x03)<<10)	      \
+			      | ((unsigned)(d)->bytes[1]<<2)	      \
+			      | ((unsigned)(d)->bytes[2]>>6))
+
+/* Set sign [this assumes sign previously 0] */
+#define decimal128SetSign(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 decimal128SetExpCon(d, e) {				      \
+  (d)->bytes[0]|=(uint8_t)((e)>>10);				      \
+  (d)->bytes[1] =(uint8_t)(((e)&0x3fc)>>2);			      \
+  (d)->bytes[2]|=(uint8_t)(((e)&0x03)<<6);}
+
+/* ------------------------------------------------------------------ */
+/* decimal128Show -- display a decimal128 in hexadecimal [debug aid]  */
+/*   d128 -- the number to show					      */
+/* ------------------------------------------------------------------ */
+/* Also shows sign/cob/expconfields extracted */
+void decimal128Show(const decimal128 *d128) {
+  char buf[DECIMAL128_Bytes*2+1];
+  Int i, j=0;
+
+  if (DECLITEND) {
+    for (i=0; i<DECIMAL128_Bytes; i++, j+=2) {
+      sprintf(&buf[j], "%02x", d128->bytes[15-i]);
+      }
+    printf(" D128> %s [S:%d Cb:%02x Ec:%02x] LittleEndian\n", buf,
+	   d128->bytes[15]>>7, (d128->bytes[15]>>2)&0x1f,
+	   ((d128->bytes[15]&0x3)<<10)|(d128->bytes[14]<<2)|
+	   (d128->bytes[13]>>6));
+    }
+   else {
+    for (i=0; i<DECIMAL128_Bytes; i++, j+=2) {
+      sprintf(&buf[j], "%02x", d128->bytes[i]);
+      }
+    printf(" D128> %s [S:%d Cb:%02x Ec:%02x] BigEndian\n", buf,
+	   decimal128Sign(d128), decimal128Comb(d128),
+	   decimal128ExpCon(d128));
+    }
+  } /* decimal128Show */
+#endif