decNumberLocal.h

/* Local definitions for the decNumber C Library.
   Copyright (C) 2007 Free Software Foundation, Inc.
   Contributed by IBM Corporation.  Author Mike Cowlishaw.

   This file is part of GCC.

   GCC is free software; you can redistribute it and/or modify it under
   the terms of the GNU General Public License as published by the Free
   Software Foundation; either version 2, or (at your option) any later
   version.

   In addition to the permissions in the GNU General Public License,
   the Free Software Foundation gives you unlimited permission to link
   the compiled version of this file into combinations with other
   programs, and to distribute those combinations without any
   restriction coming from the use of this file.  (The General Public
   License restrictions do apply in other respects; for example, they
   cover modification of the file, and distribution when not linked
   into a combine executable.)

   GCC is distributed in the hope that it will be useful, but WITHOUT ANY
   WARRANTY; without even the implied warranty of MERCHANTABILITY or
   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   for more details.

   You should have received a copy of the GNU General Public License
   along with GCC; see the file COPYING.  If not, write to the Free
   Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
   02110-1301, USA.  */

/* ------------------------------------------------------------------ */
/* decNumber package local type, tuning, and macro definitions	      */
/* ------------------------------------------------------------------ */
/* This header file is included by all modules in the decNumber	      */
/* library, and contains local type definitions, tuning parameters,   */
/* etc.	 It should not need to be used by application programs.	      */
/* decNumber.h or one of decDouble (etc.) must be included first.     */
/* ------------------------------------------------------------------ */

#ifndef DECNUMBERLOCAL_H
#define DECNUMBERLOCAL_H

  #define DECVERSION	"decNumber 3.53" /* Package Version [16 max.] */
  #define DECNLAUTHOR	"Mike Cowlishaw"	      /* Who to blame */

  #include "libdecnumber/dconfig.h"
  #include "libdecnumber/decContext.h"

  /* Conditional code flag -- set this to match hardware platform     */
  /* 1=little-endian, 0=big-endian	                              */
  #if WORDS_BIGENDIAN
  #define DECLITEND 0
  #else
  #define DECLITEND 1
  #endif

  /* Conditional code flag -- set this to 1 for best performance      */
  #define DECUSE64  1	      /* 1=use int64s, 0=int32 & smaller only */

  /* Conditional check flags -- set these to 0 for best performance   */
  #define DECCHECK  0	      /* 1 to enable robust checking	      */
  #define DECALLOC  0	      /* 1 to enable memory accounting	      */
  #define DECTRACE  0	      /* 1 to trace certain internals, etc.   */

  /* Tuning parameter for decNumber (arbitrary precision) module      */
  #define DECBUFFER 36	      /* Size basis for local buffers.	This  */
			      /* should be a common maximum precision */
			      /* rounded up to a multiple of 4; must  */
			      /* be zero or positive.		      */

  /* ---------------------------------------------------------------- */
  /* Definitions for all modules (general-purpose)		      */
  /* ---------------------------------------------------------------- */

  /* Local names for common types -- for safety, decNumber modules do */
  /* not use int or long directly.				      */
  #define Flag	 uint8_t
  #define Byte	 int8_t
  #define uByte	 uint8_t
  #define Short	 int16_t
  #define uShort uint16_t
  #define Int	 int32_t
  #define uInt	 uint32_t
  #define Unit	 decNumberUnit
  #if DECUSE64
  #define Long	 int64_t
  #define uLong	 uint64_t
  #endif

  /* Development-use definitions				      */
  typedef long int LI;	      /* for printf arguments only	      */
  #define DECNOINT  0	      /* 1 to check no internal use of 'int'  */
  #if DECNOINT
    /* if these interfere with your C includes, do not set DECNOINT   */
    #define  int ?	      /* enable to ensure that plain C 'int'  */
    #define  long ??	      /* .. or 'long' types are not used      */
  #endif

  /* Shared lookup tables					      */
  extern const uByte  DECSTICKYTAB[10]; /* re-round digits if sticky  */
  extern const uLong  DECPOWERS[19];    /* powers of ten table        */
  /* The following are included from decDPD.h			      */
  extern const uShort DPD2BIN[1024];	/* DPD -> 0-999		      */
  extern const uShort BIN2DPD[1000];	/* 0-999 -> DPD		      */
  extern const uInt   DPD2BINK[1024];	/* DPD -> 0-999000	      */
  extern const uInt   DPD2BINM[1024];	/* DPD -> 0-999000000	      */
  extern const uByte  DPD2BCD8[4096];	/* DPD -> ddd + len	      */
  extern const uByte  BIN2BCD8[4000];	/* 0-999 -> ddd + len	      */
  extern const uShort BCD2DPD[2458];	/* 0-0x999 -> DPD (0x999=2457)*/

  /* LONGMUL32HI -- set w=(u*v)>>32, where w, u, and v are uInts      */
  /* (that is, sets w to be the high-order word of the 64-bit result; */
  /* the low-order word is simply u*v.)				      */
  /* This version is derived from Knuth via Hacker's Delight;	      */
  /* it seems to optimize better than some others tried		      */
  #define LONGMUL32HI(w, u, v) {	     \
    uInt u0, u1, v0, v1, w0, w1, w2, t;	     \
    u0=u & 0xffff; u1=u>>16;		     \
    v0=v & 0xffff; v1=v>>16;		     \
    w0=u0*v0;				     \
    t=u1*v0 + (w0>>16);			     \
    w1=t & 0xffff; w2=t>>16;		     \
    w1=u0*v1 + w1;			     \
    (w)=u1*v1 + w2 + (w1>>16);}

  /* ROUNDUP -- round an integer up to a multiple of n		      */
  #define ROUNDUP(i, n) ((((i)+(n)-1)/n)*n)

  /* ROUNDDOWN -- round an integer down to a multiple of n	      */
  #define ROUNDDOWN(i, n) (((i)/n)*n)
  #define ROUNDDOWN4(i)	  ((i)&~3)	/* special for n=4	      */

  /* References to multi-byte sequences under different sizes	      */
  /* Refer to a uInt from four bytes starting at a char* or uByte*,   */
  /* etc.							      */
  #define UINTAT(b)   (*((uInt	 *)(b)))
  #define USHORTAT(b) (*((uShort *)(b)))
  #define UBYTEAT(b)  (*((uByte	 *)(b)))

  /* X10 and X100 -- multiply integer i by 10 or 100		      */
  /* [shifts are usually faster than multiply; could be conditional]  */
  #define X10(i)  (((i)<<1)+((i)<<3))
  #define X100(i) (((i)<<2)+((i)<<5)+((i)<<6))

  /* MAXI and MINI -- general max & min (not in ANSI) for integers    */
  #define MAXI(x,y) ((x)<(y)?(y):(x))
  #define MINI(x,y) ((x)>(y)?(y):(x))

  /* Useful constants						      */
  #define BILLION      1000000000	     /* 10**9		      */
  /* CHARMASK: 0x30303030 for ASCII/UTF8; 0xF0F0F0F0 for EBCDIC	      */
  #define CHARMASK ((((((((uInt)'0')<<8)+'0')<<8)+'0')<<8)+'0')


  /* ---------------------------------------------------------------- */
  /* Definitions for arbitrary-precision modules (only valid after    */
  /* decNumber.h has been included)				      */
  /* ---------------------------------------------------------------- */

  /* Limits and constants					      */
  #define DECNUMMAXP 999999999	/* maximum precision code can handle  */
  #define DECNUMMAXE 999999999	/* maximum adjusted exponent ditto    */
  #define DECNUMMINE -999999999 /* minimum adjusted exponent ditto    */
  #if (DECNUMMAXP != DEC_MAX_DIGITS)
    #error Maximum digits mismatch
  #endif
  #if (DECNUMMAXE != DEC_MAX_EMAX)
    #error Maximum exponent mismatch
  #endif
  #if (DECNUMMINE != DEC_MIN_EMIN)
    #error Minimum exponent mismatch
  #endif

  /* Set DECDPUNMAX -- the maximum integer that fits in DECDPUN	      */
  /* digits, and D2UTABLE -- the initializer for the D2U table	      */
  #if	DECDPUN==1
    #define DECDPUNMAX 9
    #define D2UTABLE {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,  \
		      18,19,20,21,22,23,24,25,26,27,28,29,30,31,32, \
		      33,34,35,36,37,38,39,40,41,42,43,44,45,46,47, \
		      48,49}
  #elif DECDPUN==2
    #define DECDPUNMAX 99
    #define D2UTABLE {0,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,  \
		      11,11,12,12,13,13,14,14,15,15,16,16,17,17,18, \
		      18,19,19,20,20,21,21,22,22,23,23,24,24,25}
  #elif DECDPUN==3
    #define DECDPUNMAX 999
    #define D2UTABLE {0,1,1,1,2,2,2,3,3,3,4,4,4,5,5,5,6,6,6,7,7,7,  \
		      8,8,8,9,9,9,10,10,10,11,11,11,12,12,12,13,13, \
		      13,14,14,14,15,15,15,16,16,16,17}
  #elif DECDPUN==4
    #define DECDPUNMAX 9999
    #define D2UTABLE {0,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,6,  \
		      6,6,6,7,7,7,7,8,8,8,8,9,9,9,9,10,10,10,10,11, \
		      11,11,11,12,12,12,12,13}
  #elif DECDPUN==5
    #define DECDPUNMAX 99999
    #define D2UTABLE {0,1,1,1,1,1,2,2,2,2,2,3,3,3,3,3,4,4,4,4,4,5,  \
		      5,5,5,5,6,6,6,6,6,7,7,7,7,7,8,8,8,8,8,9,9,9,  \
		      9,9,10,10,10,10}
  #elif DECDPUN==6
    #define DECDPUNMAX 999999
    #define D2UTABLE {0,1,1,1,1,1,1,2,2,2,2,2,2,3,3,3,3,3,3,4,4,4,  \
		      4,4,4,5,5,5,5,5,5,6,6,6,6,6,6,7,7,7,7,7,7,8,  \
		      8,8,8,8,8,9}
  #elif DECDPUN==7
    #define DECDPUNMAX 9999999
    #define D2UTABLE {0,1,1,1,1,1,1,1,2,2,2,2,2,2,2,3,3,3,3,3,3,3,  \
		      4,4,4,4,4,4,4,5,5,5,5,5,5,5,6,6,6,6,6,6,6,7,  \
		      7,7,7,7,7,7}
  #elif DECDPUN==8
    #define DECDPUNMAX 99999999
    #define D2UTABLE {0,1,1,1,1,1,1,1,1,2,2,2,2,2,2,2,2,3,3,3,3,3,  \
		      3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,6,6,6,  \
		      6,6,6,6,6,7}
  #elif DECDPUN==9
    #define DECDPUNMAX 999999999
    #define D2UTABLE {0,1,1,1,1,1,1,1,1,1,2,2,2,2,2,2,2,2,2,3,3,3,  \
		      3,3,3,3,3,3,4,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,  \
		      5,5,6,6,6,6}
  #elif defined(DECDPUN)
    #error DECDPUN must be in the range 1-9
  #endif

  /* ----- Shared data (in decNumber.c) ----- */
  /* Public lookup table used by the D2U macro (see below)	      */
  #define DECMAXD2U 49
  extern const uByte d2utable[DECMAXD2U+1];

  /* ----- Macros ----- */
  /* ISZERO -- return true if decNumber dn is a zero		      */
  /* [performance-critical in some situations]			      */
  #define ISZERO(dn) decNumberIsZero(dn)     /* now just a local name */

  /* D2U -- return the number of Units needed to hold d digits	      */
  /* (runtime version, with table lookaside for small d)	      */
  #if DECDPUN==8
    #define D2U(d) ((unsigned)((d)<=DECMAXD2U?d2utable[d]:((d)+7)>>3))
  #elif DECDPUN==4
    #define D2U(d) ((unsigned)((d)<=DECMAXD2U?d2utable[d]:((d)+3)>>2))
  #else
    #define D2U(d) ((d)<=DECMAXD2U?d2utable[d]:((d)+DECDPUN-1)/DECDPUN)
  #endif
  /* SD2U -- static D2U macro (for compile-time calculation)	      */
  #define SD2U(d) (((d)+DECDPUN-1)/DECDPUN)

  /* MSUDIGITS -- returns digits in msu, from digits, calculated      */
  /* using D2U							      */
  #define MSUDIGITS(d) ((d)-(D2U(d)-1)*DECDPUN)

  /* D2N -- return the number of decNumber structs that would be      */
  /* needed to contain that number of digits (and the initial	      */
  /* decNumber struct) safely.	Note that one Unit is included in the */
  /* initial structure.	 Used for allocating space that is aligned on */
  /* a decNumber struct boundary. */
  #define D2N(d) \
    ((((SD2U(d)-1)*sizeof(Unit))+sizeof(decNumber)*2-1)/sizeof(decNumber))

  /* TODIGIT -- macro to remove the leading digit from the unsigned   */
  /* integer u at column cut (counting from the right, LSD=0) and     */
  /* place it as an ASCII character into the character pointed to by  */
  /* c.	 Note that cut must be <= 9, and the maximum value for u is   */
  /* 2,000,000,000 (as is needed for negative exponents of	      */
  /* subnormals).  The unsigned integer pow is used as a temporary    */
  /* variable. */
  #define TODIGIT(u, cut, c, pow) {	  \
    *(c)='0';				  \
    pow=DECPOWERS[cut]*2;		  \
    if ((u)>pow) {			  \
      pow*=4;				  \
      if ((u)>=pow) {(u)-=pow; *(c)+=8;}  \
      pow/=2;				  \
      if ((u)>=pow) {(u)-=pow; *(c)+=4;}  \
      pow/=2;				  \
      }					  \
    if ((u)>=pow) {(u)-=pow; *(c)+=2;}	  \
    pow/=2;				  \
    if ((u)>=pow) {(u)-=pow; *(c)+=1;}	  \
    }

  /* ---------------------------------------------------------------- */
  /* Definitions for fixed-precision modules (only valid after	      */
  /* decSingle.h, decDouble.h, or decQuad.h has been included)	      */
  /* ---------------------------------------------------------------- */

  /* bcdnum -- a structure describing a format-independent finite     */
  /* number, whose coefficient is a string of bcd8 uBytes	      */
  typedef struct {
    uByte   *msd;	      /* -> most significant digit	      */
    uByte   *lsd;	      /* -> least ditto			      */
    uInt     sign;	      /* 0=positive, DECFLOAT_Sign=negative   */
    Int	     exponent;	      /* Unadjusted signed exponent (q), or   */
			      /* DECFLOAT_NaN etc. for a special      */
    } bcdnum;

  /* Test if exponent or bcdnum exponent must be a special, etc.      */
  #define EXPISSPECIAL(exp) ((exp)>=DECFLOAT_MinSp)
  #define EXPISINF(exp) (exp==DECFLOAT_Inf)
  #define EXPISNAN(exp) (exp==DECFLOAT_qNaN || exp==DECFLOAT_sNaN)
  #define NUMISSPECIAL(num) (EXPISSPECIAL((num)->exponent))

  /* Refer to a 32-bit word or byte in a decFloat (df) by big-endian  */
  /* (array) notation (the 0 word or byte contains the sign bit),     */
  /* automatically adjusting for endianness; similarly address a word */
  /* in the next-wider format (decFloatWider, or dfw)		      */
  #define DECWORDS  (DECBYTES/4)
  #define DECWWORDS (DECWBYTES/4)
  #if DECLITEND
    #define DFWORD(df, off) ((df)->words[DECWORDS-1-(off)])
    #define DFBYTE(df, off) ((df)->bytes[DECBYTES-1-(off)])
    #define DFWWORD(dfw, off) ((dfw)->words[DECWWORDS-1-(off)])
  #else
    #define DFWORD(df, off) ((df)->words[off])
    #define DFBYTE(df, off) ((df)->bytes[off])
    #define DFWWORD(dfw, off) ((dfw)->words[off])
  #endif

  /* Tests for sign or specials, directly on DECFLOATs		      */
  #define DFISSIGNED(df)   (DFWORD(df, 0)&0x80000000)
  #define DFISSPECIAL(df) ((DFWORD(df, 0)&0x78000000)==0x78000000)
  #define DFISINF(df)	  ((DFWORD(df, 0)&0x7c000000)==0x78000000)
  #define DFISNAN(df)	  ((DFWORD(df, 0)&0x7c000000)==0x7c000000)
  #define DFISQNAN(df)	  ((DFWORD(df, 0)&0x7e000000)==0x7c000000)
  #define DFISSNAN(df)	  ((DFWORD(df, 0)&0x7e000000)==0x7e000000)

  /* Shared lookup tables					      */
  extern const uInt   DECCOMBMSD[64];	/* Combination field -> MSD   */
  extern const uInt   DECCOMBFROM[48];	/* exp+msd -> Combination     */

  /* Private generic (utility) routine				      */
  #if DECCHECK || DECTRACE
    extern void decShowNum(const bcdnum *, const char *);
  #endif

  /* Format-dependent macros and constants			      */
  #if defined(DECPMAX)

    /* Useful constants						      */
    #define DECPMAX9  (ROUNDUP(DECPMAX, 9)/9)  /* 'Pmax' in 10**9s    */
    /* Top words for a zero					      */
    #define SINGLEZERO	 0x22500000
    #define DOUBLEZERO	 0x22380000
    #define QUADZERO	 0x22080000
    /* [ZEROWORD is defined to be one of these in the DFISZERO macro] */

    /* Format-dependent common tests:				      */
    /*	 DFISZERO   -- test for (any) zero			      */
    /*	 DFISCCZERO -- test for coefficient continuation being zero   */
    /*	 DFISCC01   -- test for coefficient contains only 0s and 1s   */
    /*	 DFISINT    -- test for finite and exponent q=0		      */
    /*	 DFISUINT01 -- test for sign=0, finite, exponent q=0, and     */
    /*		       MSD=0 or 1				      */
    /*	 ZEROWORD is also defined here.				      */
    /* In DFISZERO the first test checks the least-significant word   */
    /* (most likely to be non-zero); the penultimate tests MSD and    */
    /* DPDs in the signword, and the final test excludes specials and */
    /* MSD>7.  DFISINT similarly has to allow for the two forms of    */
    /* MSD codes.  DFISUINT01 only has to allow for one form of MSD   */
    /* code.							      */
    #if DECPMAX==7
      #define ZEROWORD SINGLEZERO
      /* [test macros not needed except for Zero]		      */
      #define DFISZERO(df)  ((DFWORD(df, 0)&0x1c0fffff)==0	   \
			  && (DFWORD(df, 0)&0x60000000)!=0x60000000)
    #elif DECPMAX==16
      #define ZEROWORD DOUBLEZERO
      #define DFISZERO(df)  ((DFWORD(df, 1)==0			   \
			  && (DFWORD(df, 0)&0x1c03ffff)==0	   \
			  && (DFWORD(df, 0)&0x60000000)!=0x60000000))
      #define DFISINT(df) ((DFWORD(df, 0)&0x63fc0000)==0x22380000  \
			 ||(DFWORD(df, 0)&0x7bfc0000)==0x6a380000)
      #define DFISUINT01(df) ((DFWORD(df, 0)&0xfbfc0000)==0x22380000)
      #define DFISCCZERO(df) (DFWORD(df, 1)==0			   \
			  && (DFWORD(df, 0)&0x0003ffff)==0)
      #define DFISCC01(df)  ((DFWORD(df, 0)&~0xfffc9124)==0	   \
			  && (DFWORD(df, 1)&~0x49124491)==0)
    #elif DECPMAX==34
      #define ZEROWORD QUADZERO
      #define DFISZERO(df)  ((DFWORD(df, 3)==0			   \
			  &&  DFWORD(df, 2)==0			   \
			  &&  DFWORD(df, 1)==0			   \
			  && (DFWORD(df, 0)&0x1c003fff)==0	   \
			  && (DFWORD(df, 0)&0x60000000)!=0x60000000))
      #define DFISINT(df) ((DFWORD(df, 0)&0x63ffc000)==0x22080000  \
			 ||(DFWORD(df, 0)&0x7bffc000)==0x6a080000)
      #define DFISUINT01(df) ((DFWORD(df, 0)&0xfbffc000)==0x22080000)
      #define DFISCCZERO(df) (DFWORD(df, 3)==0			   \
			  &&  DFWORD(df, 2)==0			   \
			  &&  DFWORD(df, 1)==0			   \
			  && (DFWORD(df, 0)&0x00003fff)==0)

      #define DFISCC01(df)   ((DFWORD(df, 0)&~0xffffc912)==0	   \
			  &&  (DFWORD(df, 1)&~0x44912449)==0	   \
			  &&  (DFWORD(df, 2)&~0x12449124)==0	   \
			  &&  (DFWORD(df, 3)&~0x49124491)==0)
    #endif

    /* Macros to test if a certain 10 bits of a uInt or pair of uInts */
    /* are a canonical declet [higher or lower bits are ignored].     */
    /* declet is at offset 0 (from the right) in a uInt:	      */
    #define CANONDPD(dpd) (((dpd)&0x300)==0 || ((dpd)&0x6e)!=0x6e)
    /* declet is at offset k (a multiple of 2) in a uInt:	      */
    #define CANONDPDOFF(dpd, k) (((dpd)&(0x300<<(k)))==0	    \
      || ((dpd)&(((uInt)0x6e)<<(k)))!=(((uInt)0x6e)<<(k)))
    /* declet is at offset k (a multiple of 2) in a pair of uInts:    */
    /* [the top 2 bits will always be in the more-significant uInt]   */
    #define CANONDPDTWO(hi, lo, k) (((hi)&(0x300>>(32-(k))))==0	    \
      || ((hi)&(0x6e>>(32-(k))))!=(0x6e>>(32-(k)))		    \
      || ((lo)&(((uInt)0x6e)<<(k)))!=(((uInt)0x6e)<<(k)))

    /* Macro to test whether a full-length (length DECPMAX) BCD8      */
    /* coefficient is zero					      */
    /* test just the LSWord first, then the remainder		      */
    #if DECPMAX==7
      #define ISCOEFFZERO(u) (UINTAT((u)+DECPMAX-4)==0		    \
	&& UINTAT((u)+DECPMAX-7)==0)
    #elif DECPMAX==16
      #define ISCOEFFZERO(u) (UINTAT((u)+DECPMAX-4)==0		    \
	&& (UINTAT((u)+DECPMAX-8)+UINTAT((u)+DECPMAX-12)	    \
	   +UINTAT((u)+DECPMAX-16))==0)
    #elif DECPMAX==34
      #define ISCOEFFZERO(u) (UINTAT((u)+DECPMAX-4)==0		    \
	&& (UINTAT((u)+DECPMAX-8) +UINTAT((u)+DECPMAX-12)	    \
	   +UINTAT((u)+DECPMAX-16)+UINTAT((u)+DECPMAX-20)	    \
	   +UINTAT((u)+DECPMAX-24)+UINTAT((u)+DECPMAX-28)	    \
	   +UINTAT((u)+DECPMAX-32)+USHORTAT((u)+DECPMAX-34))==0)
    #endif

    /* Macros and masks for the exponent continuation field and MSD   */
    /* Get the exponent continuation from a decFloat *df as an Int    */
    #define GETECON(df) ((Int)((DFWORD((df), 0)&0x03ffffff)>>(32-6-DECECONL)))
    /* Ditto, from the next-wider format			      */
    #define GETWECON(df) ((Int)((DFWWORD((df), 0)&0x03ffffff)>>(32-6-DECWECONL)))
    /* Get the biased exponent similarly			      */
    #define GETEXP(df)	((Int)(DECCOMBEXP[DFWORD((df), 0)>>26]+GETECON(df)))
    /* Get the unbiased exponent similarly			      */
    #define GETEXPUN(df) ((Int)GETEXP(df)-DECBIAS)
    /* Get the MSD similarly (as uInt)				      */
    #define GETMSD(df)	 (DECCOMBMSD[DFWORD((df), 0)>>26])

    /* Compile-time computes of the exponent continuation field masks */
    /* full exponent continuation field:			      */
    #define ECONMASK ((0x03ffffff>>(32-6-DECECONL))<<(32-6-DECECONL))
    /* same, not including its first digit (the qNaN/sNaN selector):  */
    #define ECONNANMASK ((0x01ffffff>>(32-6-DECECONL))<<(32-6-DECECONL))

    /* Macros to decode the coefficient in a finite decFloat *df into */
    /* a BCD string (uByte *bcdin) of length DECPMAX uBytes	      */

    /* In-line sequence to convert 10 bits at right end of uInt dpd   */
    /* to three BCD8 digits starting at uByte u.  Note that an extra  */
    /* byte is written to the right of the three digits because this  */
    /* moves four at a time for speed; the alternative macro moves    */
    /* exactly three bytes					      */
    #define dpd2bcd8(u, dpd) {				 \
      UINTAT(u)=UINTAT(&DPD2BCD8[((dpd)&0x3ff)*4]);}

    #define dpd2bcd83(u, dpd) {				 \
      *(u)=DPD2BCD8[((dpd)&0x3ff)*4];			 \
      *(u+1)=DPD2BCD8[((dpd)&0x3ff)*4+1];		 \
      *(u+2)=DPD2BCD8[((dpd)&0x3ff)*4+2];}

    /* Decode the declets.  After extracting each one, it is decoded  */
    /* to BCD8 using a table lookup (also used for variable-length    */
    /* decode).	 Each DPD decode is 3 bytes BCD8 plus a one-byte      */
    /* length which is not used, here).	 Fixed-length 4-byte moves    */
    /* are fast, however, almost everywhere, and so are used except   */
    /* for the final three bytes (to avoid overrun).  The code below  */
    /* is 36 instructions for Doubles and about 70 for Quads, even    */
    /* on IA32.							      */

    /* Two macros are defined for each format:			      */
    /*	 GETCOEFF extracts the coefficient of the current format      */
    /*	 GETWCOEFF extracts the coefficient of the next-wider format. */
    /* The latter is a copy of the next-wider GETCOEFF using DFWWORD. */

    #if DECPMAX==7
    #define GETCOEFF(df, bcd) {				 \
      uInt sourhi=DFWORD(df, 0);			 \
      *(bcd)=(uByte)DECCOMBMSD[sourhi>>26];		 \
      dpd2bcd8(bcd+1, sourhi>>10);			 \
      dpd2bcd83(bcd+4, sourhi);}
    #define GETWCOEFF(df, bcd) {			 \
      uInt sourhi=DFWWORD(df, 0);			 \
      uInt sourlo=DFWWORD(df, 1);			 \
      *(bcd)=(uByte)DECCOMBMSD[sourhi>>26];		 \
      dpd2bcd8(bcd+1, sourhi>>8);			 \
      dpd2bcd8(bcd+4, (sourhi<<2) | (sourlo>>30));	 \
      dpd2bcd8(bcd+7, sourlo>>20);			 \
      dpd2bcd8(bcd+10, sourlo>>10);			 \
      dpd2bcd83(bcd+13, sourlo);}

    #elif DECPMAX==16
    #define GETCOEFF(df, bcd) {				 \
      uInt sourhi=DFWORD(df, 0);			 \
      uInt sourlo=DFWORD(df, 1);			 \
      *(bcd)=(uByte)DECCOMBMSD[sourhi>>26];		 \
      dpd2bcd8(bcd+1, sourhi>>8);			 \
      dpd2bcd8(bcd+4, (sourhi<<2) | (sourlo>>30));	 \
      dpd2bcd8(bcd+7, sourlo>>20);			 \
      dpd2bcd8(bcd+10, sourlo>>10);			 \
      dpd2bcd83(bcd+13, sourlo);}
    #define GETWCOEFF(df, bcd) {			 \
      uInt sourhi=DFWWORD(df, 0);			 \
      uInt sourmh=DFWWORD(df, 1);			 \
      uInt sourml=DFWWORD(df, 2);			 \
      uInt sourlo=DFWWORD(df, 3);			 \
      *(bcd)=(uByte)DECCOMBMSD[sourhi>>26];		 \
      dpd2bcd8(bcd+1, sourhi>>4);			 \
      dpd2bcd8(bcd+4, ((sourhi)<<6) | (sourmh>>26));	 \
      dpd2bcd8(bcd+7, sourmh>>16);			 \
      dpd2bcd8(bcd+10, sourmh>>6);			 \
      dpd2bcd8(bcd+13, ((sourmh)<<4) | (sourml>>28));	 \
      dpd2bcd8(bcd+16, sourml>>18);			 \
      dpd2bcd8(bcd+19, sourml>>8);			 \
      dpd2bcd8(bcd+22, ((sourml)<<2) | (sourlo>>30));	 \
      dpd2bcd8(bcd+25, sourlo>>20);			 \
      dpd2bcd8(bcd+28, sourlo>>10);			 \
      dpd2bcd83(bcd+31, sourlo);}

    #elif DECPMAX==34
    #define GETCOEFF(df, bcd) {				 \
      uInt sourhi=DFWORD(df, 0);			 \
      uInt sourmh=DFWORD(df, 1);			 \
      uInt sourml=DFWORD(df, 2);			 \
      uInt sourlo=DFWORD(df, 3);			 \
      *(bcd)=(uByte)DECCOMBMSD[sourhi>>26];		 \
      dpd2bcd8(bcd+1, sourhi>>4);			 \
      dpd2bcd8(bcd+4, ((sourhi)<<6) | (sourmh>>26));	 \
      dpd2bcd8(bcd+7, sourmh>>16);			 \
      dpd2bcd8(bcd+10, sourmh>>6);			 \
      dpd2bcd8(bcd+13, ((sourmh)<<4) | (sourml>>28));	 \
      dpd2bcd8(bcd+16, sourml>>18);			 \
      dpd2bcd8(bcd+19, sourml>>8);			 \
      dpd2bcd8(bcd+22, ((sourml)<<2) | (sourlo>>30));	 \
      dpd2bcd8(bcd+25, sourlo>>20);			 \
      dpd2bcd8(bcd+28, sourlo>>10);			 \
      dpd2bcd83(bcd+31, sourlo);}

      #define GETWCOEFF(df, bcd) {??} /* [should never be used]	      */
    #endif

    /* Macros to decode the coefficient in a finite decFloat *df into */
    /* a base-billion uInt array, with the least-significant	      */
    /* 0-999999999 'digit' at offset 0.				      */

    /* Decode the declets.  After extracting each one, it is decoded  */
    /* to binary using a table lookup.	Three tables are used; one    */
    /* the usual DPD to binary, the other two pre-multiplied by 1000  */
    /* and 1000000 to avoid multiplication during decode.  These      */
    /* tables can also be used for multiplying up the MSD as the DPD  */
    /* code for 0 through 9 is the identity.			      */
    #define DPD2BIN0 DPD2BIN	     /* for prettier code	      */

    #if DECPMAX==7
    #define GETCOEFFBILL(df, buf) {			      \
      uInt sourhi=DFWORD(df, 0);			      \
      (buf)[0]=DPD2BIN0[sourhi&0x3ff]			      \
	      +DPD2BINK[(sourhi>>10)&0x3ff]		      \
	      +DPD2BINM[DECCOMBMSD[sourhi>>26]];}

    #elif DECPMAX==16
    #define GETCOEFFBILL(df, buf) {			      \
      uInt sourhi, sourlo;				      \
      sourlo=DFWORD(df, 1);				      \
      (buf)[0]=DPD2BIN0[sourlo&0x3ff]			      \
	      +DPD2BINK[(sourlo>>10)&0x3ff]		      \
	      +DPD2BINM[(sourlo>>20)&0x3ff];		      \
      sourhi=DFWORD(df, 0);				      \
      (buf)[1]=DPD2BIN0[((sourhi<<2) | (sourlo>>30))&0x3ff]   \
	      +DPD2BINK[(sourhi>>8)&0x3ff]		      \
	      +DPD2BINM[DECCOMBMSD[sourhi>>26]];}

    #elif DECPMAX==34
    #define GETCOEFFBILL(df, buf) {			      \
      uInt sourhi, sourmh, sourml, sourlo;		      \
      sourlo=DFWORD(df, 3);				      \
      (buf)[0]=DPD2BIN0[sourlo&0x3ff]			      \
	      +DPD2BINK[(sourlo>>10)&0x3ff]		      \
	      +DPD2BINM[(sourlo>>20)&0x3ff];		      \
      sourml=DFWORD(df, 2);				      \
      (buf)[1]=DPD2BIN0[((sourml<<2) | (sourlo>>30))&0x3ff]   \
	      +DPD2BINK[(sourml>>8)&0x3ff]		      \
	      +DPD2BINM[(sourml>>18)&0x3ff];		      \
      sourmh=DFWORD(df, 1);				      \
      (buf)[2]=DPD2BIN0[((sourmh<<4) | (sourml>>28))&0x3ff]   \
	      +DPD2BINK[(sourmh>>6)&0x3ff]		      \
	      +DPD2BINM[(sourmh>>16)&0x3ff];		      \
      sourhi=DFWORD(df, 0);				      \
      (buf)[3]=DPD2BIN0[((sourhi<<6) | (sourmh>>26))&0x3ff]   \
	      +DPD2BINK[(sourhi>>4)&0x3ff]		      \
	      +DPD2BINM[DECCOMBMSD[sourhi>>26]];}

    #endif

    /* Macros to decode the coefficient in a finite decFloat *df into */
    /* a base-thousand uInt array, with the least-significant 0-999   */
    /* 'digit' at offset 0.					      */

    /* Decode the declets.  After extracting each one, it is decoded  */
    /* to binary using a table lookup.				      */
    #if DECPMAX==7
    #define GETCOEFFTHOU(df, buf) {			      \
      uInt sourhi=DFWORD(df, 0);			      \
      (buf)[0]=DPD2BIN[sourhi&0x3ff];			      \
      (buf)[1]=DPD2BIN[(sourhi>>10)&0x3ff];		      \
      (buf)[2]=DECCOMBMSD[sourhi>>26];}

    #elif DECPMAX==16
    #define GETCOEFFTHOU(df, buf) {			      \
      uInt sourhi, sourlo;				      \
      sourlo=DFWORD(df, 1);				      \
      (buf)[0]=DPD2BIN[sourlo&0x3ff];			      \
      (buf)[1]=DPD2BIN[(sourlo>>10)&0x3ff];		      \
      (buf)[2]=DPD2BIN[(sourlo>>20)&0x3ff];		      \
      sourhi=DFWORD(df, 0);				      \
      (buf)[3]=DPD2BIN[((sourhi<<2) | (sourlo>>30))&0x3ff];   \
      (buf)[4]=DPD2BIN[(sourhi>>8)&0x3ff];		      \
      (buf)[5]=DECCOMBMSD[sourhi>>26];}

    #elif DECPMAX==34
    #define GETCOEFFTHOU(df, buf) {			      \
      uInt sourhi, sourmh, sourml, sourlo;		      \
      sourlo=DFWORD(df, 3);				      \
      (buf)[0]=DPD2BIN[sourlo&0x3ff];			      \
      (buf)[1]=DPD2BIN[(sourlo>>10)&0x3ff];		      \
      (buf)[2]=DPD2BIN[(sourlo>>20)&0x3ff];		      \
      sourml=DFWORD(df, 2);				      \
      (buf)[3]=DPD2BIN[((sourml<<2) | (sourlo>>30))&0x3ff];   \
      (buf)[4]=DPD2BIN[(sourml>>8)&0x3ff];		      \
      (buf)[5]=DPD2BIN[(sourml>>18)&0x3ff];		      \
      sourmh=DFWORD(df, 1);				      \
      (buf)[6]=DPD2BIN[((sourmh<<4) | (sourml>>28))&0x3ff];   \
      (buf)[7]=DPD2BIN[(sourmh>>6)&0x3ff];		      \
      (buf)[8]=DPD2BIN[(sourmh>>16)&0x3ff];		      \
      sourhi=DFWORD(df, 0);				      \
      (buf)[9]=DPD2BIN[((sourhi<<6) | (sourmh>>26))&0x3ff];   \
      (buf)[10]=DPD2BIN[(sourhi>>4)&0x3ff];		      \
      (buf)[11]=DECCOMBMSD[sourhi>>26];}

    #endif

    /* Set a decFloat to the maximum positive finite number (Nmax)    */
    #if DECPMAX==7
    #define DFSETNMAX(df)	     \
      {DFWORD(df, 0)=0x77f3fcff;}
    #elif DECPMAX==16
    #define DFSETNMAX(df)	     \
      {DFWORD(df, 0)=0x77fcff3f;     \
       DFWORD(df, 1)=0xcff3fcff;}
    #elif DECPMAX==34
    #define DFSETNMAX(df)	     \
      {DFWORD(df, 0)=0x77ffcff3;     \
       DFWORD(df, 1)=0xfcff3fcf;     \
       DFWORD(df, 2)=0xf3fcff3f;     \
       DFWORD(df, 3)=0xcff3fcff;}
    #endif

  /* [end of format-dependent macros and constants]		      */
  #endif

#endif