v10i062: config.c v4.2, Everything you wanted to know about your C compiler (and more)
Steven Pemberton
steven at cwi.nl
Wed Feb 14 12:58:48 AEST 1990
Posting-number: Volume 10, Issue 62
Submitted-by: steven at cwi.nl (Steven Pemberton)
Archive-name: config42
Here is the latest version of config.c, a program that finds out all
sorts of properties of your machine and C compiler. It will also
optionally produce the ANSI C float.h and limits.h files for you.
All documentation is in the file itself.
Steven Pemberton, CWI, Amsterdam; steven at cwi.nl
"Let us go then you and I/while the night is laid out against the sky/like a
smear of mustard on an old pork pie"
"Nice poem Tom. I have suggestions for changes though, why not come over?"- Ez.
-----------------CUT HERE-------------------------
: This is a shell archive.
: Extract with 'sh this_file'.
echo 'Start of pack.out, part 01 out of 01:'
if test -s 'config.c'
then echo '*** I will not over-write existing file config.c'
else
echo 'x - config.c'
sed 's/^X//' > 'config.c' << 'EOF'
X/* Everything you wanted to know about your machine and C compiler,
X but didn't know who to ask. */
X
X#ifndef VERSION
X#define VERSION "4.2"
X#endif
X
X/* Author: Steven Pemberton, CWI, Amsterdam; steven at cwi.nl
X Bugfixes and upgrades gratefully received.
X
X Copyright (c) 1988, 1989, 1990 Steven Pemberton, CWI, Amsterdam.
X All rights reserved.
X
X COMPILING
X With luck and a following wind, just the following will work:
X cc config.c -o config
X You may get some messages about unreachable code. This is OK.
X
X If your compiler doesn't support: add flag:
X signed char (eg pcc) -DNO_SC
X unsigned char -DNO_UC
X unsigned short and long -DNO_UI
X void -DNO_VOID
X signal(), or setjmp/longjmp() -DNO_SIG
X
X Try to compile first with no flags, and see if you get any errors -
X you might be surprised. (Most non-ANSI compilers need -DNO_SC, though.)
X Some compilers need a -f flag for floating point.
X
X If your C preprocessor doesn't have the predefined __FILE__ macro, and
X you don't want to call this file config.c but, say, params.c, add the
X flag -D__FILE__=\"params.c\" .
X
X Some naughty compilers define __STDC__, but don't really support it
X (typically they define __STDC__ as 0). If this is the case for you,
X add flag -DNO_STDC. (To those compiler writers: for shame).
X
X Some bad compilers won't accept the line "#include __FILE__" or
X "#ifdef __FILE__". Add flag -DNO_FILE. In that case, this file *must*
X be called config.c.
X
X Don't use any optimisation flags: the program may not work if you do.
X Though "while (a+1.0-a-1.0 == 0.0)" may look like "while(1)" to an
X optimiser, to a floating-point unit there's a world of difference.
X
X Some compilers offer various flags for different floating point
X modes; it's worth trying all possible combinations of these.
X
X Add -DID=\"name\" if you want the machine/flags identified in the output.
X
X While it is not our policy to support defective compilers, pity has been
X taken on people with compilers that can't produce object files bigger than
X 32k (especially since it was an easy addition). Compile the program
X into separate parts like this:
X cc -DSEP -DPASS0 -o p0.o <other flags> config.c
X cc -DSEP -DPASS1 -o p1.o <other flags> config.c
X cc -DSEP -DPASS2 -o p2.o <other flags> config.c
X cc -DSEP -DPASS3 -o p3.o <other flags> config.c
X cc -o config p0.o p1.o p2.o p3.o
X
X SYSTEM DEPENDENCIES
X You may possibly need to add some calls to signal() for other sorts of
X exception on your machine than SIGFPE, and SIGOVER. See lines beginning
X #ifdef SIGxxx in main() (and communicate the differences to me!).
X
X OUTPUT
X Run without argument to get the information as English text. If run
X with argument -l (e.g. config -l), output is a series of #define's for
X the ANSI standard limits.h include file, excluding MB_MAX_CHAR. If run
X with argument -f, output is a series of #define's for the ANSI standard
X float.h include file (according to ANSI C Draft of May 13, 1988).
X Flag -v gives verbose output: output includes the English text above
X as C comments. The program exit(0)'s if everything went ok, otherwise
X it exits with a positive number, telling how many problems there were.
X
X VERIFYING THE COMPILER
X If, having produced the float.h and limits.h header files, you want to
X verify that the compiler reads them back correctly (there are a lot of
X boundary cases, of course, like minimum and maximum numbers), you can
X recompile config.c with -DVERIFY set (plus the other flags that you used
X when compiling the version that produced the header files). This then
X recompiles the program so that it #includes "limits.h" and "float.h",
X and checks that the constants it finds there are the same as the
X constants it produces. Run the resulting program with config -fl.
X Very few compilers have passed without error.
X
X You can also use this option if your compiler already has both files,
X and you want to confirm that this program produces the right results.
X
X TROUBLESHOOTING.
X This program is now quite trustworthy, and suspicious and wrong output
X may well be caused by bugs in the compiler, not in the program (however
X of course, this is not guaranteed, and no responsibility can be
X accepted, etc.)
X
X The program only works if overflows are ignored by the C system or
X are catchable with signal().
X
X If the program fails to run to completion (often with the error message
X "Unexpected signal at point x"), this often turns out to be a bug in the
X C compiler's run-time system. Check what was about to be printed, and
X try to narrow the problem down.
X
X Another possible problem is that you have compiled the program to produce
X loss-of-precision arithmetic traps. The program cannot cope with these,
X and you should re-compile without them. (They should never be the default).
X
X Make sure you compiled with optimisation turned off.
X
X Output preceded by *** WARNING: identifies behaviour of the C system
X deemed incorrect by the program. Likely problems are that printf or
X scanf don't cope properly with certain boundary numbers: this program
X goes to a lot of trouble to calculate its values, and these values
X are mostly boundary numbers. Experience has shown that often printf
X cannot cope with these values, and so in an attempt to increase
X confidence in the output, for each float and double that is printed,
X the printed value is checked by using sscanf to read it back.
X Care is taken that numbers are printed with enough digits to uniquely
X identify them, and therefore that they can be read back identically.
X If the number read back is different, then there is probably a bug in
X printf or sscanf, and the program prints the warning message.
X If the two numbers in the warning look identical, then printf is more
X than likely rounding the last digit(s) incorrectly. To put you at ease
X that the two really are different, the bit patterns of the two numbers
X are also printed. The difference is very likely in the last bit.
X Many scanf's read the minimum double back as 0.0, and similarly cause
X overflow when reading the maximum double. The program quite ruthlessly
X declares all these behaviours faulty. The point is that if you get
X one of these warnings, the output may be wrong, so you should check
X the result carefully if you intend to use the results. Of course, printf
X and sscanf may both be wrong, and cancel each other out, so you should
X check the output carefully anyway.
X
X The warning that "a cast didn't work" refers to cases like this:
X
X float f;
X #define C 1.234567890123456789
X f= C;
X if (f != (float) C) printf ("Wrong!");
X
X A faulty compiler will widen f to double and ignore the cast to float,
X and because there is more accuracy in a double than a float, fail to
X recognise that they are the same. In the actual case in point, f and C
X are passed as parameters to a function that discovers they are not equal,
X so it's just possible that the error was in the parameter passing,
X not in the cast (see function Validate()).
X For ANSI C, which has float constants, the error message is "constant has
X wrong precision".
X
X REPORTING PROBLEMS
X If the program doesn't work for you for any reason that can't be
X narrowed down to a problem in the C compiler, or it has to be changed in
X order to get it to compile, or it produces suspicious output (like a very
X low maximum float, for instance), please mail the problem and an example
X of the incorrect output to steven at cwi.nl or ..!hp4nl!cwi.nl!steven, so that
X improvements can be worked into future versions; cwi.nl is the European
X backbone, and is connected to uunet and other fine hosts.
X
X The program tries to catch and diagnose bugs in the compiler/run-time
X system. I would be especially pleased to have reports of failures so
X that I can improve this service.
X
X I apologise unreservedly for the contorted use of the preprocessor...
X
X THE SMALL PRINT
X You may copy and distribute verbatim copies of this source file.
X
X You may modify this source file, and copy and distribute such
X modified versions, provided that you leave the copyright notice
X at the top of the file and also cause the modified file to carry
X prominent notices stating that you changed the files and the date
X of any change; and cause the whole of any work that you distribute
X or publish, that in whole or in part contains or is a derivative of
X this program or any part thereof, to be licensed at no charge to
X all third parties on terms identical to those here.
X
X If you do have a fix to any problem, please send it to me, so that
X other people can have the benefits.
X
X While every effort has been taken to make this program as reliable as
X possible, no responsibility can be taken for the correctness of the
X output, or suitability for any particular use.
X
X ACKNOWLEDGEMENTS
X Many people have given time and ideas to making this program what it is.
X To all of them thanks, and apologies for not mentioning them by name.
X
X HISTORY
X 4.0 Added -f and -l options, and warnings
X 4.1 Added VERIFY
X 4.2 Added SEP
X Fixed eps/epsneg
X Added check for pseudo-unsigned chars
X Added description for each #define output
X Added check for absence of defines during verify
X Added prototypes
X Added NO_STDC and NO_FILE
X Fixed alignments output
X*/
X
X#ifndef NO_FILE
X#ifndef __FILE__
X#define __FILE__ "config.c"
X#endif
X#endif
X
X/* If PASS isn't defined, then this is the first pass over this file. */
X#ifndef PASS
X#ifndef SEP
X#define PASS 1
X#define PASS0 1
X#define PASS1 1
X#endif /* SEP */
X
X/* A description of the ANSI constants */
X#define D_CHAR_BIT "Number of bits in a storage unit"
X#define D_CHAR_MAX "Maximum char"
X#define D_CHAR_MIN "Minimum char"
X#define D_SCHAR_MAX "Maximum signed char"
X#define D_SCHAR_MIN "Minimum signed char"
X#define D_UCHAR_MAX "Maximum unsigned char (minimum is always 0)"
X
X#define D_INT_MAX "Maximum %s"
X#define D_INT_MIN "Minimum %s"
X#define D_UINT_MAX "Maximum unsigned %s (minimum is always 0)"
X
X#define D_FLT_ROUNDS "Addition rounds to 0: zero, 1: nearest, 2: +inf, 3: -inf, -1: unknown"
X#define D_FLT_RADIX "Radix of exponent representation"
X#define D_MANT_DIG "Number of base-FLT_RADIX digits in the mantissa of a %s"
X#define D_DIG "Number of decimal digits of precision in a %s"
X#define D_MIN_EXP "Minimum int x such that FLT_RADIX**(x-1) is a normalised %s"
X#define D_MIN_10_EXP "Minimum int x such that 10**x is a normalised %s"
X#define D_MAX_EXP "Maximum int x such that FLT_RADIX**(x-1) is a representable %s"
X#define D_MAX_10_EXP "Maximum int x such that 10**x is a representable %s"
X#define D_MAX "Maximum %s"
X#define D_EPSILON "Minimum %s x such that 1.0+x != 1.0"
X#define D_MIN "Minimum normalised %s"
X
X/* Procedure just marks the functions that don't return a result */
X#ifdef NO_VOID
X#define Procedure int
X#else
X#define Procedure void
X#endif
X
X/* Some bad compilers define __STDC__, when they don't support it.
X Compile with -DNO_STDC to get round this.
X*/
X#ifndef NO_STDC
X#ifdef __STDC__
X#define STDC
X#endif
X#endif
X
X/* Stuff different for ANSI C, and old C:
X ARGS and NOARGS are used for function prototypes.
X Volatile is used to reduce the chance of optimisation,
X and to prevent variables being put in registers (when setjmp/longjmp
X wouldn't work as we want)
X Long_double is the longest floating point type available.
X stdc is used in tests like "if (stdc)", which is less ugly than #ifdef.
X U is output after unsigned constants.
X */
X#ifdef STDC
X
X#define ARGS(x) x
X#define NOARGS (void)
X#define Volatile volatile
X#define Long_double long double
X#define stdc 1
X#define U "U"
X
X#else /* Old style C */
X
X#define ARGS(x) ()
X#define NOARGS ()
X#define Volatile static
X#define Long_double double
X#define stdc 0
X#define U ""
X
X#endif /* STDC */
X
X/* include files */
X#include <stdio.h>
X
X#ifdef NO_SIG
X#define jmp_buf int
X#else
X#include <signal.h>
X#include <setjmp.h>
X#endif
X
X#ifdef VERIFY
X#include "limits.h"
X#include "float.h"
X#endif
X
X#define Vprintf if (V) printf
X#define Unexpected(place) if (setjmp(lab)!=0) croak(place)
X#define fabs(x) (((x)<0.0)?(-x):(x))
X
X#endif /* PASS */
X
X#ifdef PASS0
X
X/* Prototypes for what's to come: */
X
Xchar *malloc ARGS((unsigned size));
XProcedure exit ARGS((int status));
X
Xchar *f_rep ARGS((int precision, Long_double val));
X
Xint cprop NOARGS;
Xint basic NOARGS;
XProcedure sprop NOARGS;
XProcedure iprop NOARGS;
XProcedure lprop NOARGS;
XProcedure usprop NOARGS;
XProcedure uiprop NOARGS;
XProcedure ulprop NOARGS;
Xint fprop ARGS((int bits_per_byte));
Xint dprop ARGS((int bits_per_byte));
Xint ldprop ARGS((int bits_per_byte));
XProcedure efprop ARGS((int fprec, int dprec, int lprec));
XProcedure edprop ARGS((int fprec, int dprec, int lprec));
XProcedure eldprop ARGS((int fprec, int dprec, int lprec));
X
Xint setmode ARGS((char *s));
XProcedure farewell ARGS((int bugs));
XProcedure describe ARGS((char *description, char *extra));
XProcedure check_defines NOARGS;
XProcedure bitpattern ARGS((char *p, unsigned int size));
Xint ceil_log ARGS((int base, Long_double x));
XProcedure croak ARGS((int place));
XProcedure eek_a_bug ARGS((char *problem));
XProcedure endian ARGS((int bits_per_byte));
Xint exponent ARGS((Long_double x, double *fract, int *exp));
Xint floor_log ARGS((int base, Long_double x));
XProcedure f_define ARGS((char *desc, char *extra, char *sort, char *name,
X int prec, Long_double val, char *mark));
XProcedure i_define ARGS((char *desc, char *extra, char *sort, char *name,
X long val, long req, char *mark));
XProcedure u_define ARGS((char *desc, char *extra, char *sort, char *name,
X unsigned long val, unsigned long req, char *mark));
X
X#ifdef NO_SIG /* There's no signal(), or setjmp/longjmp() */
X
X /* Dummy routines instead */
X
X Procedure setjmp ARGS((int lab));
X
X int lab=1;
X int setjmp(lab) int lab; { return(0); }
X Procedure signal(i, p) int i, (*p)(); {}
X
X#else
X jmp_buf lab;
X Procedure overflow(sig) int sig; { /* what to do on over/underflow */
X signal(sig, overflow);
X longjmp(lab, 1);
X }
X
X#endif /*NO_SIG*/
X
Xint V= 0, /* verbose */
X L= 0, /* produce limits.h */
X F= 0, /* produce float.h */
X bugs=0; /* The number of (possible) bugs in the output */
X
Xchar co[4], oc[4]; /* Comment starter and ender symbols */
X
Xint bits_per_byte; /* the number of bits per unit returned by sizeof() */
Xint flt_rounds; /* The calculated value of FLT_ROUNDS */
Xint flt_radix; /* The calculated value of FLT_RADIX */
X
X#ifdef TEST
X/* Set the fp modes on a SUN with 68881 chip, to check that different
X rounding modes etc. get properly detected.
X Compile with additional flag -DTEST, and run with additional parameter
X +hex-number, to set the 68881 mode register to hex-number
X*/
X
X/* Bits 0x30 = rounding mode: */
X#define ROUND_BITS 0x30
X#define TO_NEAREST 0x00
X#define TO_ZERO 0x10
X#define TO_MINUS_INF 0x20
X#define TO_PLUS_INF 0x30 /* The SUN FP user's guide seems to be wrong here */
X
X/* Bits 0xc0 = extended rounding: */
X#define EXT_BITS 0xc0
X#define ROUND_EXTENDED 0x00
X#define ROUND_SINGLE 0x40
X#define ROUND_DOUBLE 0x80
X
X/* Enabled traps: */
X#define EXE_INEX1 0x100
X#define EXE_INEX2 0x200
X#define EXE_DZ 0x400
X#define EXE_UNFL 0x800
X#define EXE_OVFL 0x1000
X#define EXE_OPERR 0x2000
X#define EXE_SNAN 0x4000
X#define EXE_BSUN 0x8000
X
X/* Only used for testing, on a Sun with 68881 chip */
X/* Print the FP mode */
Xprintmode(new) unsigned new; {
X fpmode_(&new);
X printf("New fp mode:\n");
X printf(" Round toward ");
X switch (new & ROUND_BITS) {
X case TO_NEAREST: printf("nearest"); break;
X case TO_ZERO: printf("zero"); break;
X case TO_MINUS_INF: printf("minus infinity"); break;
X case TO_PLUS_INF: printf("plus infinity"); break;
X default: printf("???"); break;
X }
X
X printf("\n Extended rounding precision: ");
X
X switch (new & EXT_BITS) {
X case ROUND_EXTENDED: printf("extended"); break;
X case ROUND_SINGLE: printf("single"); break;
X case ROUND_DOUBLE: printf("double"); break;
X default: printf("???"); break;
X }
X
X printf("\n Enabled exceptions:");
X if (new & (unsigned) EXE_INEX1) printf(" inex1");
X if (new & (unsigned) EXE_INEX2) printf(" inex2");
X if (new & (unsigned) EXE_DZ) printf(" dz");
X if (new & (unsigned) EXE_UNFL) printf(" unfl");
X if (new & (unsigned) EXE_OVFL) printf(" ovfl");
X if (new & (unsigned) EXE_OPERR) printf(" operr");
X if (new & (unsigned) EXE_SNAN) printf(" snan");
X if (new & (unsigned) EXE_BSUN) printf(" bsun");
X printf("\n");
X}
X
X/* Only used for testing, on a Sun with 68881 chip */
X/* Set the FP mode */
Xint setmode(s) char *s; {
X unsigned mode=0, dig;
X char c;
X
X while (*s) {
X c= *s++;
X if (c>='0' && c<='9') dig= c-'0';
X else if (c>='a' && c<='f') dig= c-'a'+10;
X else if (c>='A' && c<='F') dig= c-'A'+10;
X else return 1;
X mode= mode<<4 | dig;
X }
X printmode(mode);
X return 0;
X}
X#else
Xint setmode(s) char *s; {
X fprintf(stderr, "Can't set mode: not compiled with TEST\n");
X return(1);
X}
X#endif
X
XProcedure farewell(bugs) int bugs; {
X if (bugs > 0) {
X printf("\n%sFor hints on dealing with the problems above", co);
X printf("\n see the section 'TROUBLESHOOTING' in the file ");
X printf("%s%s\n", __FILE__, oc);
X }
X exit(bugs);
X}
X
X/* The program has received a signal where it wasn't expecting one */
XProcedure croak(place) int place; {
X printf("*** Unexpected signal at point %d\n", place);
X farewell(bugs+1); /* An exit isn't essential here, but avoids loops */
X}
X
Xmain(argc, argv) int argc; char *argv[]; {
X int dprec, fprec, lprec;
X unsigned int size;
X long total;
X int i; char *s; int bad;
X
X#ifdef SIGFPE
X signal(SIGFPE, overflow);
X#endif
X#ifdef SIGOVER
X signal(SIGOVER, overflow);
X#endif
X/* Add more calls as necessary */
X
X Unexpected(1);
X
X bad=0;
X for (i=1; i < argc; i++) {
X s= argv[i];
X if (*s == '-') {
X s++;
X while (*s) {
X switch (*(s++)) {
X case 'v': V=1; break;
X case 'l': L=1; break;
X case 'f': F=1; break;
X default: bad=1; break;
X }
X }
X } else if (*s == '+') {
X s++;
X bad= setmode(s);
X } else bad= 1;
X }
X if (bad) {
X fprintf(stderr,
X "Usage: %s [-vlf]\n v=Verbose l=Limits.h f=Float.h\n",
X argv[0]);
X exit(1);
X }
X if (L || F) {
X co[0]= '/'; oc[0]= ' ';
X co[1]= '*'; oc[1]= '*';
X co[2]= ' '; oc[2]= '/';
X co[3]= '\0'; oc[3]= '\0';
X } else {
X co[0]= '\0'; oc[0]= '\0';
X V=1;
X }
X
X if (L) printf("%slimits.h%s\n", co, oc);
X if (F) printf("%sfloat.h%s\n", co, oc);
X#ifdef ID
X printf("%sProduced on %s by config version %s, CWI, Amsterdam%s\n",
X co, ID, VERSION, oc);
X#else
X printf("%sProduced by config version %s, CWI, Amsterdam%s\n",
X co, VERSION, oc);
X#endif
X
X#ifdef VERIFY
X printf("%sVerification phase%s\n", co, oc);
X#endif
X
X#ifdef NO_SIG
X Vprintf("%sCompiled without signal(): %s%s\n",
X co,
X "there's nothing that can be done if overflow occurs",
X oc);
X#endif
X#ifdef NO_SC
X Vprintf("%sCompiled without signed char%s\n", co, oc);
X#endif
X#ifdef NO_UC
X Vprintf("%Compiled without unsigned char%s\n", co, oc);
X#endif
X#ifdef NO_UI
X Vprintf("%Compiled without unsigned short or long%s\n", co, oc);
X#endif
X#ifdef __STDC__
X Vprintf("%sCompiler claims to be ANSI C level %d%s\n",
X co, __STDC__, oc);
X#else
X Vprintf("%sCompiler does not claim to be ANSI C%s\n", co, oc);
X#endif
X printf("\n");
X check_defines();
X
X bits_per_byte= basic();
X Vprintf("\n");
X if (F||V) {
X fprec= fprop(bits_per_byte);
X dprec= dprop(bits_per_byte);
X lprec= ldprop(bits_per_byte);
X efprop(fprec, dprec, lprec);
X edprop(fprec, dprec, lprec);
X eldprop(fprec, dprec, lprec);
X }
X if (V) {
X /* An extra goody: the approximate amount of data-space */
X /* Allocate store until no more available */
X size=1<<((bits_per_byte*sizeof(int))-2);
X total=0;
X while (size!=0) {
X while (malloc(size)!=(char *)NULL) total+=(size/2);
X size/=2;
X }
X
X Vprintf("%sMemory mallocatable ~= %ld Kbytes%s\n",
X co, (total+511)/512, oc);
X }
X farewell(bugs);
X return bugs; /* To keep compilers and lint happy */
X}
X
XProcedure eek_a_bug(problem) char *problem; {
X /* The program has discovered a problem */
X printf("\n%s*** WARNING: %s%s\n", co, problem, oc);
X bugs++;
X}
X
XProcedure describe(description, extra) char *description, *extra; {
X /* Produce the description for a #define */
X printf(" %s", co);
X printf(description, extra);
X printf("%s\n", oc);
X}
X
XProcedure i_define(desc, extra, sort, name, val, req, mark)
X char *desc, *extra, *sort, *name; long val, req; char *mark; {
X /* Produce a #define for a signed int type */
X describe(desc, extra);
X if (val >= 0) {
X printf("#define %s%s %ld%s\n", sort, name, val, mark);
X } else {
X printf("#define %s%s (%ld%s)\n", sort, name, val, mark);
X }
X if (val != req) {
X printf("%s*** Verify failed for above #define!\n", co);
X printf(" Compiler has %ld for value%s\n\n", req, oc);
X bugs++;
X }
X Vprintf("\n");
X}
X
XProcedure u_define(desc, extra, sort, name, val, req, mark)
X char *desc, *extra, *sort, *name; unsigned long val, req; char *mark; {
X /* Produce a #define for an unsigned value */
X describe(desc, extra);
X printf("#define %s%s %lu%s%s\n", sort, name, val, U, mark);
X if (val != req) {
X printf("%s*** Verify failed for above #define!\n", co);
X printf(" Compiler has %lu for value%s\n\n", req, oc);
X bugs++;
X }
X Vprintf("\n");
X}
X
XProcedure f_define(desc, extra, sort, name, precision, val, mark)
X char *desc, *extra, *sort, *name; int precision;
X Long_double val; char *mark; {
X /* Produce a #define for a float/double/long double */
X describe(desc, extra);
X if (stdc) {
X printf("#define %s%s %s%s\n",
X sort, name, f_rep(precision, val), mark);
X } else if (*mark == 'F') {
X /* non-ANSI C has no float constants, so cast the constant */
X printf("#define %s%s ((float)%s)\n",
X sort, name, f_rep(precision, val));
X } else {
X printf("#define %s%s %s\n", sort, name, f_rep(precision, val));
X }
X Vprintf("\n");
X}
X
Xint floor_log(base, x) int base; Long_double x; {
X /* return floor(log base(x)) */
X int r=0;
X while (x>=base) { r++; x/=base; }
X return r;
X}
X
Xint ceil_log(base, x) int base; Long_double x; {
X int r=0;
X while (x>1.0) { r++; x/=base; }
X return r;
X}
X
Xint exponent(x, fract, exp) Long_double x; double *fract; int *exp; {
X /* Split x into a fraction and a power of ten;
X returns 0 if x is unusable, 1 otherwise.
X Only used for error messages about faulty output.
X */
X int r=0, neg=0;
X Long_double old;
X *fract=0.0; *exp=0;
X if (x<0.0) {
X x= -x;
X neg= 1;
X }
X if (x==0.0) return 1;
X if (x>=10.0) {
X while (x>=10.0) {
X old=x; r++; x/=10.0;
X if (old==x) return 0;
X }
X } else {
X while (x<1.0) {
X old=x; r--; x*=10.0;
X if (old==x) return 0;
X }
X }
X if (neg) *fract= -x;
X else *fract=x;
X *exp=r;
X return 1;
X}
X
Xchar *f_rep(precision, val) int precision; Long_double val; {
X /* Return the floating representation of val */
X static char buf[1024];
X char *f1;
X if (sizeof(double) == sizeof(Long_double)) {
X /* Assume they're the same, and use non-stdc format */
X /* This is for stdc compilers using non-stdc libraries */
X f1= "%.*e";
X } else {
X /* It had better support Le then */
X f1= "%.*Le";
X }
X sprintf(buf, f1, precision, val);
X return buf;
X}
X
XProcedure bitpattern(p, size) char *p; unsigned int size; {
X /* Printf the bit-pattern of p */
X char c;
X int i, j;
X
X for (i=1; i<=size; i++) {
X c= *p;
X p++;
X for (j=bits_per_byte-1; j>=0; j--)
X printf("%c", (c>>j)&1 ? '1' : '0');
X if (i!=size) printf(" ");
X }
X}
X
X#define Order(x, px, mode)\
X printf("%s %s ", co, mode); for (i=0; i<sizeof(x); i++) px[i]= c[i]; \
X for (i=1; i<=sizeof(x); i++) { putchar((char)((x>>(bits_per_byte*(sizeof(x)-i)))&mask)); }\
X printf("%s\n", oc);
X
XProcedure endian(bits_per_byte) int bits_per_byte; {
X /* Printf the byte-order used on this machine */
X /*unsigned*/ short s=0;
X /*unsigned*/ int j=0;
X /*unsigned*/ long l=0;
X
X char *ps= (char *) &s,
X *pj= (char *) &j,
X *pl= (char *) &l,
X *c= "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
X unsigned int mask, i;
X
X mask=0;
X for (i=1; i<=(unsigned)bits_per_byte; i++) mask= (mask<<1)|1;
X
X if (V) {
X printf("%sCharacter order:%s\n", co, oc);
X Order(s, ps, "short:");
X Order(j, pj, "int: ");
X Order(l, pl, "long: ");
X }
X}
X
XProcedure check_defines() {
X /* ensure that all the #defines are present */
X#ifdef VERIFY
X if (L) {
X#ifndef CHAR_BIT
X printf("%s*** CHAR_BIT missing from limits.h%s\n", co, oc); bugs++;
X#endif
X#ifndef CHAR_MAX
X printf("%s*** CHAR_MAX missing from limits.h%s\n", co, oc); bugs++;
X#endif
X#ifndef CHAR_MIN
X printf("%s*** CHAR_MIN missing from limits.h%s\n", co, oc); bugs++;
X#endif
X#ifndef SCHAR_MAX
X printf("%s*** SCHAR_MAX missing from limits.h%s\n", co, oc); bugs++;
X#endif
X#ifndef SCHAR_MIN
X printf("%s*** SCHAR_MIN missing from limits.h%s\n", co, oc); bugs++;
X#endif
X#ifndef UCHAR_MAX
X printf("%s*** UCHAR_MAX missing from limits.h%s\n", co, oc); bugs++;
X#endif
X#ifndef SHRT_MAX
X printf("%s*** SHRT_MAX missing from limits.h%s\n", co, oc); bugs++;
X#endif
X#ifndef SHRT_MIN
X printf("%s*** SHRT_MIN missing from limits.h%s\n", co, oc); bugs++;
X#endif
X#ifndef INT_MAX
X printf("%s*** INT_MAX missing from limits.h%s\n", co, oc); bugs++;
X#endif
X#ifndef INT_MIN
X printf("%s*** INT_MIN missing from limits.h%s\n", co, oc); bugs++;
X#endif
X#ifndef LONG_MAX
X printf("%s*** LONG_MAX missing from limits.h%s\n", co, oc); bugs++;
X#endif
X#ifndef LONG_MIN
X printf("%s*** LONG_MIN missing from limits.h%s\n", co, oc); bugs++;
X#endif
X#ifndef USHRT_MAX
X printf("%s*** USHRT_MAX missing from limits.h%s\n", co, oc); bugs++;
X#endif
X#ifndef UINT_MAX
X printf("%s*** UINT_MAX missing from limits.h%s\n", co, oc); bugs++;
X#endif
X#ifndef ULONG_MAX
X printf("%s*** ULONG_MAX missing from limits.h%s\n", co, oc); bugs++;
X#endif
X } /* if (L) */
X
X if (F) {
X#ifndef FLT_RADIX
X printf("%s*** FLT_RADIX missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef FLT_MANT_DIG
X printf("%s*** FLT_MANT_DIG missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef FLT_DIG
X printf("%s*** FLT_DIG missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef FLT_ROUNDS
X printf("%s*** FLT_ROUNDS missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef FLT_EPSILON
X printf("%s*** FLT_EPSILON missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef FLT_MIN_EXP
X printf("%s*** FLT_MIN_EXP missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef FLT_MIN
X printf("%s*** FLT_MIN missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef FLT_MIN_10_EXP
X printf("%s*** FLT_MIN_10_EXP missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef FLT_MAX_EXP
X printf("%s*** FLT_MAX_EXP missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef FLT_MAX
X printf("%s*** FLT_MAX missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef FLT_MAX_10_EXP
X printf("%s*** FLT_MAX_10_EXP missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef DBL_MANT_DIG
X printf("%s*** DBL_MANT_DIG missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef DBL_DIG
X printf("%s*** DBL_DIG missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef DBL_EPSILON
X printf("%s*** DBL_EPSILON missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef DBL_MIN_EXP
X printf("%s*** DBL_MIN_EXP missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef DBL_MIN
X printf("%s*** DBL_MIN missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef DBL_MIN_10_EXP
X printf("%s*** DBL_MIN_10_EXP missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef DBL_MAX_EXP
X printf("%s*** DBL_MAX_EXP missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef DBL_MAX
X printf("%s*** DBL_MAX missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef DBL_MAX_10_EXP
X printf("%s*** DBL_MAX_10_EXP missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifdef STDC
X#ifndef LDBL_MANT_DIG
X printf("%s*** LDBL_MANT_DIG missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef LDBL_DIG
X printf("%s*** LDBL_DIG missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef LDBL_EPSILON
X printf("%s*** LDBL_EPSILON missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef LDBL_MIN_EXP
X printf("%s*** LDBL_MIN_EXP missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef LDBL_MIN
X printf("%s*** LDBL_MIN missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef LDBL_MIN_10_EXP
X printf("%s*** LDBL_MIN_10_EXP missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef LDBL_MAX_EXP
X printf("%s*** LDBL_MAX_EXP missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef LDBL_MAX
X printf("%s*** LDBL_MAX missing from float.h%s\n", co, oc); bugs++;
X#endif
X#ifndef LDBL_MAX_10_EXP
X printf("%s*** LDBL_MAX_10_EXP missing from float.h%s\n", co, oc); bugs++;
X#endif
X#endif /* STDC */
X } /* if (F) */
X#endif /* VERIFY */
X}
X
X#ifdef VERIFY
X#ifndef SCHAR_MAX
X#define SCHAR_MAX char_max
X#endif
X#ifndef SCHAR_MIN
X#define SCHAR_MIN char_min
X#endif
X#ifndef UCHAR_MAX
X#define UCHAR_MAX char_max
X#endif
X#endif /* VERIFY */
X
X#ifndef CHAR_BIT
X#define CHAR_BIT char_bit
X#endif
X#ifndef CHAR_MAX
X#define CHAR_MAX char_max
X#endif
X#ifndef CHAR_MIN
X#define CHAR_MIN char_min
X#endif
X#ifndef SCHAR_MAX
X#define SCHAR_MAX char_max
X#endif
X#ifndef SCHAR_MIN
X#define SCHAR_MIN char_min
X#endif
X#ifndef UCHAR_MAX
X#define UCHAR_MAX char_max
X#endif
X
Xint cprop() {
X /* Properties of type char */
X Volatile char c, char_max, char_min;
X Volatile int bits_per_byte, is_signed;
X long char_bit;
X
X Unexpected(2);
X
X /* Calculate number of bits per character *************************/
X c=1; bits_per_byte=0;
X do { c=c<<1; bits_per_byte++; } while(c!=0);
X c= (char)(-1);
X if (((int)c)<0) is_signed=1;
X else is_signed=0;
X Vprintf("%sChar = %d bits, %ssigned%s\n",
X co, (int)sizeof(c)*bits_per_byte, (is_signed?"":"un"), oc);
X char_bit=(long)(sizeof(c)*bits_per_byte);
X if (L) i_define(D_CHAR_BIT, "",
X "CHAR", "_BIT", char_bit, (long) CHAR_BIT, "");
X
X c=0; char_max=0;
X c++;
X if (setjmp(lab)==0) { /* Yields char_max */
X while (c>char_max) {
X char_max=c;
X c++;
X }
X } else {
X Vprintf("%sCharacter overflow generates a trap!%s\n", co, oc);
X }
X c=0; char_min=0;
X c--;
X if (setjmp(lab)==0) { /* Yields char_min */
X while (c<char_min) {
X char_min=c;
X c--;
X }
X }
X if (is_signed && char_min == 0) {
X Vprintf("%sBEWARE! Chars are pseudo-unsigned:%s\n", co, oc);
X Vprintf("%s %s%s%s\n",
X "They contain only nonnegative values, ",
X "but sign extend when used as integers.", co, oc);
X }
X Unexpected(3);
X
X if (L) {
X i_define(D_CHAR_MAX, "",
X "CHAR", "_MAX", (long) char_max, (long) CHAR_MAX, "");
X i_define(D_CHAR_MIN, "",
X "CHAR", "_MIN", (long) char_min, (long) CHAR_MIN, "");
X if (is_signed) {
X i_define(D_SCHAR_MAX, "",
X "SCHAR", "_MAX", (long) char_max,
X (long) SCHAR_MAX, "");
X i_define(D_SCHAR_MIN, "",
X "SCHAR", "_MIN", (long) char_min,
X (long) SCHAR_MIN, "");
X } else {
X i_define(D_UCHAR_MAX, "",
X "UCHAR", "_MAX", (long) char_max,
X (long) UCHAR_MAX, "");
X }
X
X if (is_signed) {
X#ifndef NO_UC
X Volatile unsigned char c, char_max;
X c=0; char_max=0;
X c++;
X if (setjmp(lab)==0) { /* Yields char_max */
X while (c>char_max) {
X char_max=c;
X c++;
X }
X }
X Unexpected(4);
X i_define(D_UCHAR_MAX, "",
X "UCHAR", "_MAX", (long) char_max,
X (long) UCHAR_MAX, "");
X#endif
X } else {
X#ifndef NO_SC /* Define NO_SC if the next line gives a syntax error */
X Volatile signed char c, char_max, char_min;
X c=0; char_max=0;
X c++;
X if (setjmp(lab)==0) { /* Yields char_max */
X while (c>char_max) {
X char_max=c;
X c++;
X }
X }
X c=0; char_min=0;
X c--;
X if (setjmp(lab)==0) { /* Yields char_min */
X while (c<char_min) {
X char_min=c;
X c--;
X }
X }
X Unexpected(5);
X i_define(D_SCHAR_MIN, "",
X "SCHAR", "_MIN", (long) char_min,
X (long) SCHAR_MIN, "");
X i_define(D_SCHAR_MAX, "",
X "SCHAR", "_MAX", (long) char_max,
X (long) SCHAR_MAX, "");
X#endif /* NO_SC */
X }
X }
X return bits_per_byte;
X}
X
Xint basic() {
X /* The properties of the basic types.
X Returns number of bits per sizeof unit */
X Volatile int bits_per_byte;
X struct{char i1; char c1;} schar;
X struct{short i2; char c2;} sshort;
X struct{int i3; char c3;} sint;
X struct{long i4; char c4;} slong;
X
X bits_per_byte= cprop();
X
X /* Shorts, ints and longs *****************************************/
X Vprintf("%sShort=%d int=%d long=%d float=%d double=%d bits %s\n",
X co,
X (int) sizeof(short)*bits_per_byte,
X (int) sizeof(int)*bits_per_byte,
X (int) sizeof(long)*bits_per_byte,
X (int) sizeof(float)*bits_per_byte,
X (int) sizeof(double)*bits_per_byte, oc);
X if (stdc) {
X Vprintf("%sLong double=%d bits%s\n",
X co, (int) sizeof(Long_double)*bits_per_byte, oc);
X }
X Vprintf("%sChar pointers = %d bits%s%s\n",
X co, (int)sizeof(char *)*bits_per_byte,
X sizeof(char *)>sizeof(int)?" BEWARE! larger than int!":"",
X oc);
X Vprintf("%sInt pointers = %d bits%s%s\n",
X co, (int)sizeof(int *)*bits_per_byte,
X sizeof(int *)>sizeof(int)?" BEWARE! larger than int!":"",
X oc);
X
X /* Alignment constants ********************************************/
X Vprintf("%sAlignments used for char=%ld short=%ld int=%ld long=%ld%s\n",
X co,
X ((long)&schar.c1)-((long)&schar.i1),
X ((long)&sshort.c2)-((long)&sshort.i2),
X ((long)&sint.c3)-((long)&sint.i3),
X ((long)&slong.c4)-((long)&slong.i4),
X oc);
X
X /* Ten little endians *********************************************/
X
X endian(bits_per_byte);
X
X /* Pointers *******************************************************/
X if (V) {
X if ("abcd"=="abcd")
X printf("%sStrings are shared%s\n", co, oc);
X else printf("%sStrings are not shared%s\n", co, oc);
X }
X
X sprop();
X iprop();
X lprop();
X usprop();
X uiprop();
X ulprop();
X
X Unexpected(6);
X
X return bits_per_byte;
X}
X
X#else /* not PASS0 */
X
X#ifdef SEP
Xextern jmp_buf lab;
Xextern int V, L, F, bugs, bits_per_byte;
Xextern char co[], oc[];
Xextern char *f_rep();
X#endif /* SEP */
X#endif /* ifdef PASS0 */
X
X/* As I said, I apologise for the contortions below. The functions are
X expanded by the preprocessor twice or three times (for float and double,
X and maybe for long double, and for short, int and long). That way,
X I never make a change to one that I forget to make to the other.
X You can look on it as C's fault for not supporting multi-line macro's.
X This whole file is read 3 times by the preprocessor, with PASSn set for
X n=1, 2 or 3, to decide which parts to reprocess.
X*/
X
X/* #undef on an already undefined thing is (wrongly) flagged as an error
X by some compilers, therefore the #ifdef that follows:
X*/
X#ifdef Number
X#undef Number
X#undef THING
X#undef Thing
X#undef thing
X#undef FPROP
X#undef Fname
X#undef Store
X#undef Sum
X#undef Diff
X#undef Mul
X#undef Div
X#undef ZERO
X#undef HALF
X#undef ONE
X#undef TWO
X#undef THREE
X#undef FOUR
X#undef Self
X#undef F_check
X#undef Validate
X#undef EPROP
X#undef MARK
X
X/* These are the float.h constants */
X#undef F_RADIX
X#undef F_MANT_DIG
X#undef F_DIG
X#undef F_ROUNDS
X#undef F_EPSILON
X#undef F_MIN_EXP
X#undef F_MIN
X#undef F_MIN_10_EXP
X#undef F_MAX_EXP
X#undef F_MAX
X#undef F_MAX_10_EXP
X#endif
X
X#ifdef Integer
X#undef Integer
X#undef INT
X#undef IPROP
X#undef Iname
X#undef UPROP
X#undef Uname
X#undef OK_UI
X#undef IMARK
X
X#undef I_MAX
X#undef I_MIN
X#undef U_MAX
X#endif
X
X#ifdef PASS1
X
X/* Define the things we're going to use this pass */
X
X#define Number float
X#define THING "FLOAT"
X#define Thing "Float"
X#define thing "float"
X#define Fname "FLT"
X#define FPROP fprop
X#define Store fStore
X#define Sum fSum
X#define Diff fDiff
X#define Mul fMul
X#define Div fDiv
X#define ZERO 0.0
X#define HALF 0.5
X#define ONE 1.0
X#define TWO 2.0
X#define THREE 3.0
X#define FOUR 4.0
X#define Self fSelf
X#define F_check fCheck
X#define MARK "F"
X#ifdef VERIFY
X#define Validate(prec, val, req, same) fValidate(prec, val, req, same)
X#endif
X
X#define EPROP efprop
X
X#define Integer short
X#define INT "short"
X#define IPROP sprop
X#define Iname "SHRT"
X#ifndef NO_UI
X#define OK_UI 1
X#endif
X#define IMARK ""
X
X#define UPROP usprop
X#define Uname "USHRT"
X
X#ifdef VERIFY
X#ifdef SHRT_MAX
X#define I_MAX SHRT_MAX
X#endif
X#ifdef SHRT_MIN
X#define I_MIN SHRT_MIN
X#endif
X#ifdef USHRT_MAX
X#define U_MAX USHRT_MAX
X#endif
X
X#ifdef FLT_RADIX
X#define F_RADIX FLT_RADIX
X#endif
X#ifdef FLT_MANT_DIG
X#define F_MANT_DIG FLT_MANT_DIG
X#endif
X#ifdef FLT_DIG
X#define F_DIG FLT_DIG
X#endif
X#ifdef FLT_ROUNDS
X#define F_ROUNDS FLT_ROUNDS
X#endif
X#ifdef FLT_EPSILON
X#define F_EPSILON FLT_EPSILON
X#endif
X#ifdef FLT_MIN_EXP
X#define F_MIN_EXP FLT_MIN_EXP
X#endif
X#ifdef FLT_MIN
X#define F_MIN FLT_MIN
X#endif
X#ifdef FLT_MIN_10_EXP
X#define F_MIN_10_EXP FLT_MIN_10_EXP
X#endif
X#ifdef FLT_MAX_EXP
X#define F_MAX_EXP FLT_MAX_EXP
X#endif
X#ifdef FLT_MAX
X#define F_MAX FLT_MAX
X#endif
X#ifdef FLT_MAX_10_EXP
X#define F_MAX_10_EXP FLT_MAX_10_EXP
X#endif
X#endif /* VERIFY */
X
X#endif /* PASS1 */
X
X#ifdef PASS2
X
X#define Number double
X#define THING "DOUBLE"
X#define Thing "Double"
X#define thing "double"
X#define Fname "DBL"
X#define FPROP dprop
X#define Store dStore
X#define Sum dSum
X#define Diff dDiff
X#define Mul dMul
X#define Div dDiv
X#define ZERO 0.0
X#define HALF 0.5
X#define ONE 1.0
X#define TWO 2.0
X#define THREE 3.0
X#define FOUR 4.0
X#define Self dSelf
X#define F_check dCheck
X#define MARK ""
X#ifdef VERIFY
X#define Validate(prec, val, req, same) dValidate(prec, val, req, same)
X#endif
X
X#define EPROP edprop
X
X#define Integer int
X#define INT "int"
X#define IPROP iprop
X#define Iname "INT"
X#define OK_UI 1 /* Unsigned int is always possible */
X#define IMARK ""
X
X#define UPROP uiprop
X#define Uname "UINT"
X
X#ifdef VERIFY
X#ifdef INT_MAX
X#define I_MAX INT_MAX
X#endif
X#ifdef INT_MIN
X#define I_MIN INT_MIN
X#endif
X#ifdef UINT_MAX
X#define U_MAX UINT_MAX
X#endif
X
X#ifdef DBL_MANT_DIG
X#define F_MANT_DIG DBL_MANT_DIG
X#endif
X#ifdef DBL_DIG
X#define F_DIG DBL_DIG
X#endif
X#ifdef DBL_EPSILON
X#define F_EPSILON DBL_EPSILON
X#endif
X#ifdef DBL_MIN_EXP
X#define F_MIN_EXP DBL_MIN_EXP
X#endif
X#ifdef DBL_MIN
X#define F_MIN DBL_MIN
X#endif
X#ifdef DBL_MIN_10_EXP
X#define F_MIN_10_EXP DBL_MIN_10_EXP
X#endif
X#ifdef DBL_MAX_EXP
X#define F_MAX_EXP DBL_MAX_EXP
X#endif
X#ifdef DBL_MAX
X#define F_MAX DBL_MAX
X#endif
X#ifdef DBL_MAX_10_EXP
X#define F_MAX_10_EXP DBL_MAX_10_EXP
X#endif
X#endif /* VERIFY */
X
X#endif /* PASS2 */
X
X#ifdef PASS3
X
X#ifdef STDC
X#define Number long double
X#endif
X
X#define THING "LONG DOUBLE"
X#define Thing "Long double"
X#define thing "long double"
X#define Fname "LDBL"
X#define FPROP ldprop
X#define Store ldStore
X#define Sum ldSum
X#define Diff ldDiff
X#define Mul ldMul
X#define Div ldDiv
X#define ZERO 0.0L
X#define HALF 0.5L
X#define ONE 1.0L
X#define TWO 2.0L
X#define THREE 3.0L
X#define FOUR 4.0L
X#define Self ldSelf
X#define F_check ldCheck
X#define MARK "L"
X#ifdef VERIFY
X#define Validate(prec, val, req, same) ldValidate(prec, val, req, same)
X#endif
X
X#define EPROP eldprop
X
X#define Integer long
X#define INT "long"
X#define IPROP lprop
X#define Iname "LONG"
X#ifndef NO_UI
X#define OK_UI 1
X#endif
X#define IMARK "L"
X
X#define UPROP ulprop
X#define Uname "ULONG"
X
X#ifdef VERIFY
X#ifdef LONG_MAX
X#define I_MAX LONG_MAX
X#endif
X#ifdef LONG_MIN
X#define I_MIN LONG_MIN
X#endif
X#ifdef ULONG_MAX
X#define U_MAX ULONG_MAX
X#endif
X
X#ifdef LDBL_MANT_DIG
X#define F_MANT_DIG LDBL_MANT_DIG
X#endif
X#ifdef LDBL_DIG
X#define F_DIG LDBL_DIG
X#endif
X#ifdef LDBL_EPSILON
X#define F_EPSILON LDBL_EPSILON
X#endif
X#ifdef LDBL_MIN_EXP
X#define F_MIN_EXP LDBL_MIN_EXP
X#endif
X#ifdef LDBL_MIN
X#define F_MIN LDBL_MIN
X#endif
X#ifdef LDBL_MIN_10_EXP
X#define F_MIN_10_EXP LDBL_MIN_10_EXP
X#endif
X#ifdef LDBL_MAX_EXP
X#define F_MAX_EXP LDBL_MAX_EXP
X#endif
X#ifdef LDBL_MAX
X#define F_MAX LDBL_MAX
X#endif
X#ifdef LDBL_MAX_10_EXP
X#define F_MAX_10_EXP LDBL_MAX_10_EXP
X#endif
X#endif /* VERIFY */
X
X#endif /* PASS3 */
X
X#ifndef I_MAX
X#define I_MAX int_max
X#endif
X#ifndef I_MIN
X#define I_MIN int_min
X#endif
X#ifndef U_MAX
X#define U_MAX int_max
X#endif
X
X#ifndef F_RADIX
X#define F_RADIX f_radix
X#endif
X#ifndef F_MANT_DIG
X#define F_MANT_DIG f_mant_dig
X#endif
X#ifndef F_DIG
X#define F_DIG f_dig
X#endif
X#ifndef F_ROUNDS
X#define F_ROUNDS f_rounds
X#endif
X#ifndef F_EPSILON
X#define F_EPSILON f_epsilon
X#endif
X#ifndef F_MIN_EXP
X#define F_MIN_EXP f_min_exp
X#endif
X#ifndef F_MIN
X#define F_MIN f_min
X#endif
X#ifndef F_MIN_10_EXP
X#define F_MIN_10_EXP f_min_10_exp
X#endif
X#ifndef F_MAX_EXP
X#define F_MAX_EXP f_max_exp
X#endif
X#ifndef F_MAX
X#define F_MAX f_max
X#endif
X#ifndef F_MAX_10_EXP
X#define F_MAX_10_EXP f_max_10_exp
X#endif
X
X#ifndef VERIFY
X#define Validate(prec, val, req, same) {;}
X#endif
X
X#ifdef Integer
X
XProcedure IPROP() {
X /* the properties of short, int, and long */
X Volatile Integer newi, int_max, maxeri, int_min, minneri;
X Volatile int ibits, ipower, two=2;
X
X /* Calculate max short/int/long ***********************************/
X /* Calculate 2**n-1 until overflow - then use the previous value */
X
X newi=1; int_max=0;
X
X if (setjmp(lab)==0) { /* Yields int_max */
X for(ipower=0; newi>int_max; ipower++) {
X int_max=newi;
X newi=newi*two+1;
X }
X Vprintf("%sOverflow of a%s %s does not generate a trap%s\n",
X co, INT[0]=='i'?"n":"", INT, oc);
X } else {
X Vprintf("%sOverflow of a%s %s generates a trap%s\n",
X co, INT[0]=='i'?"n":"", INT, oc);
X }
X Unexpected(7);
X
X /* Minimum value: assume either two's or one's complement *********/
X int_min= -int_max;
X if (setjmp(lab)==0) { /* Yields int_min */
X if (int_min-1 < int_min) int_min--;
X }
X Unexpected(8);
X
X /* Now for those daft Cybers: */
X
X maxeri=0; newi=int_max;
X
X if (setjmp(lab)==0) { /* Yields maxeri */
X for(ibits=ipower; newi>maxeri; ibits++) {
X maxeri=newi;
X newi=newi+newi+1;
X }
X }
X Unexpected(9);
X
X minneri= -maxeri;
X if (setjmp(lab)==0) { /* Yields minneri */
X if (minneri-1 < minneri) minneri--;
X }
X Unexpected(10);
X
X Vprintf("%sMaximum %s = %ld (= 2**%d-1)%s\n",
X co, INT, (long)int_max, ipower, oc);
X Vprintf("%sMinimum %s = %ld%s\n", co, INT, (long)int_min, oc);
X
X if (L) i_define(D_INT_MAX, INT,
X Iname, "_MAX", (long) int_max, (long) I_MAX, IMARK);
X if (L) i_define(D_INT_MIN, INT,
X Iname, "_MIN", (long) int_min, (long) I_MIN, IMARK);
X
X if (maxeri>int_max) {
X Vprintf("%sThere is a larger %s, %ld (= 2**%d-1), %s %s%s\n",
X co, INT, (long)maxeri, ibits,
X "but only for addition, not multiplication",
X "(I smell a Cyber!)",
X oc);
X }
X
X if (minneri<int_min) {
X Vprintf("%sThere is a smaller %s, %ld, %s %s%s\n",
X co, INT, (long)minneri,
X "but only for addition, not multiplication",
X "(I smell a Cyber!)",
X oc);
X }
X}
X
XProcedure UPROP () {
X /* The properties of unsigned short/int/long */
X#ifdef OK_UI
X Volatile unsigned Integer int_max, newi, two;
X newi=1; int_max=0; two=2;
X
X if (setjmp(lab)==0) { /* Yields int_max */
X while(newi>int_max) {
X int_max=newi;
X newi=newi*two+1;
X }
X }
X Unexpected(11);
X Vprintf("%sMaximum unsigned %s = %lu%s\n",
X co, INT, (unsigned long) int_max, oc);
X if (L) u_define(D_UINT_MAX, INT,
X Uname, "_MAX", (unsigned long) int_max,
X (unsigned long) U_MAX, IMARK);
X#endif
X}
X
X#endif /* Integer */
X
X#ifdef Number
X
X/* The following routines are intended to defeat any attempt at optimisation
X or use of extended precision, and to defeat faulty narrowing casts.
X The weird prototypes are because of widening incompatibilities.
X*/
X#ifdef STDC
X#define ARGS1(atype, a) (atype a)
X#define ARGS2(atype, a, btype, b) (atype a, btype b)
X#else
X#define ARGS1(atype, a) (a) atype a;
X#define ARGS2(atype, a, btype, b) (a, b) atype a; btype b;
X#endif
X
XProcedure Store ARGS2(Number, a, Number *, b) { *b=a; }
XNumber Sum ARGS2(Number, a, Number, b) {Number r; Store(a+b, &r); return (r); }
XNumber Diff ARGS2(Number, a, Number, b){Number r; Store(a-b, &r); return (r); }
XNumber Mul ARGS2(Number, a, Number, b) {Number r; Store(a*b, &r); return (r); }
XNumber Div ARGS2(Number, a, Number, b) {Number r; Store(a/b, &r); return (r); }
XNumber Self ARGS1(Number, a) {Number r; Store(a, &r); return (r); }
X
XProcedure F_check ARGS((int precision, Long_double val1));
X
XProcedure F_check(precision, val1) int precision; Long_double val1; {
X /* You don't think I'm going to go to all the trouble of writing
X a program that works out what all sorts of values are, only to
X have printf go and print the wrong values out, do you?
X No, you're right, so this function tries to see if printf
X has written the right value, by reading it back again.
X This introduces a new problem of course: suppose printf writes
X the correct value, and scanf reads it back wrong... oh well.
X But I'm adamant about this: the precision given is enough
X to uniquely identify the printed number, therefore I insist
X that sscanf read the number back identically. Harsh yes, but
X sometimes you've got to be cruel to be kind.
X */
X Long_double new1;
X Number val, new, diff;
X double rem;
X int e;
X char *rep;
X char *f2;
X
X if (sizeof(double) == sizeof(Long_double)) {
X /* Assume they're the same, and use non-stdc format */
X /* This is for stdc compilers using non-stdc libraries */
X f2= "%le"; /* Input */
X } else {
X /* It had better support Le then */
X f2= "%Le";
X }
X val= val1;
X rep= f_rep(precision, (Long_double) val);
X if (setjmp(lab)==0) {
X sscanf(rep, f2, &new1);
X } else {
X eek_a_bug("sscanf caused a trap");
X printf("%s scanning: %s format: %s%s\n\n", co, rep, f2, oc);
X Unexpected(12);
X return;
X }
X
X if (setjmp(lab)==0) { /* See if new is usable */
X new= new1;
X if (new != 0.0) {
X diff= val/new - 1.0;
X if (diff < 0.1) diff= 1.0;
X /* That should be enough to generate a trap */
X }
X } else {
X eek_a_bug("sscanf returned an unusable number");
X printf("%s scanning: %s with format: %s%s\n\n",
X co, rep, f2, oc);
X Unexpected(13);
X return;
X }
X
X Unexpected(14);
X if (new != val) {
X eek_a_bug("Possibly bad output from printf above");
X if (!exponent((Long_double)val, &rem, &e)) {
X printf("%s but value was an unusable number%s\n\n",
X co, oc);
X return;
X }
X printf("%s expected value around %.*fe%d, bit pattern:\n ",
X co, precision, rem, e);
X bitpattern((char *) &val, sizeof(val));
X printf ("%s\n", oc);
X printf("%s sscanf gave %s, bit pattern:\n ",
X co, f_rep(precision, (Long_double) new));
X bitpattern((char *) &new, sizeof(new));
X printf ("%s\n", oc);
X if (setjmp(lab) == 0) {
X diff= val-new;
X printf("%s difference= %s%s\n\n",
X co, f_rep(precision, (Long_double) diff), oc);
X } /* else forget it */
X Unexpected(15);
X }
X}
X
X#ifdef VERIFY
XProcedure Validate(prec, val, req, same) int prec, same; Long_double val, req; {
X /* Check that the compiler has read a #define value correctly */
X Unexpected(16);
X if (!same) {
X printf("%s*** Verify failed for above #define!\n", co);
X if (setjmp(lab) == 0) { /* for the case that req == nan */
X printf(" Compiler has %s for value%s\n",
X f_rep(prec, req), oc);
X } else {
X printf(" Compiler has %s for value%s\n",
X "an unusable number", oc);
X }
X if (setjmp(lab) == 0) {
X F_check(prec, (Long_double) req);
X } /*else forget it*/
X if (setjmp(lab) == 0) {
X if (req > 0.0 && val > 0.0) {
X printf("%s difference= %s%s\n",
X co, f_rep(prec, val-req), oc);
X }
X } /*else forget it*/
X Unexpected(17);
X printf("\n");
X bugs++;
X } else if (val != req) {
X if (stdc) {
X printf("%s*** Verify failed for above #define!\n", co);
X printf(" Constant has the wrong precision%s\n",
X oc);
X } else eek_a_bug("the cast didn't work");
X printf("\n");
X bugs++;
X }
X}
X#endif /* VERIFY */
X
Xint FPROP(bits_per_byte) int bits_per_byte; {
X /* Properties of floating types, using algorithms by Cody and Waite
X from MA Malcolm, as modified by WM Gentleman and SB Marovich.
X Further extended by S Pemberton.
X
X Returns the number of digits in the fraction.
X */
X
X Volatile int
X i, f_radix, iexp, irnd, mrnd, f_rounds, f_mant_dig,
X iz, k, inf, machep, f_max_exp, f_min_exp, mx, negeps,
X mantbits, digs, f_dig, trap,
X hidden, normal, f_min_10_exp, f_max_10_exp;
X Volatile Number
X a, b, base, basein, basem1, f_epsilon, epsneg,
X eps, epsp1, etop, ebot,
X f_max, newxmax, f_min, xminner, y, y1, z, z1, z2;
X
X Unexpected(18);
X
X Vprintf("%sPROPERTIES OF %s:%s\n", co, THING, oc);
X
X /* Base and size of mantissa **************************************/
X /* First repeatedly double until adding 1 has no effect. */
X /* For instance, if base is 10, with 3 significant digits */
X /* it will try 1, 2, 4, 8, ... 512, 1024, and stop there, */
X /* since 1024 is only representable as 1020. */
X a=1.0;
X if (setjmp(lab)==0) { /* inexact trap? */
X do { a=Sum(a, a); }
X while (Diff(Diff(Sum(a, ONE), a), ONE) == ZERO);
X } else {
X fprintf(stderr, "*** Program got loss-of-precision trap!\n");
X /* And supporting those is just TOO much trouble! */
X farewell(bugs+1);
X }
X Unexpected(19);
X /* Now double until you find a number that can be added to the */
X /* above number. For 1020 this is 8 or 16, depending whether the */
X /* result is rounded or truncated. */
X /* In either case the result is 1030. 1030-1020= the base, 10. */
X b=1.0;
X do { b=Sum(b, b); } while ((base=Diff(Sum(a, b), a)) == ZERO);
X f_radix=base;
X Vprintf("%sBase = %d%s\n", co, f_radix, oc);
X
X /* Sanity check; if base<2, I can't guarantee the rest will work */
X if (f_radix < 2) {
X eek_a_bug("Function return or parameter passing faulty? (This is a guess.)");
X printf("\n");
X return(0);
X }
X
X#ifdef PASS1 /* only for FLT */
X flt_radix= f_radix;
X if (F) i_define(D_FLT_RADIX, "",
X "FLT", "_RADIX", (long) f_radix, (long) F_RADIX, "");
X#else
X if (f_radix != flt_radix) {
X printf("\n%s*** WARNING: %s %s (%d) %s%s\n",
X co, thing, "arithmetic has a different radix",
X f_radix, "from float", oc);
X bugs++;
X }
X#endif
X
X /* Now the number of digits precision: */
X f_mant_dig=0; b=1.0;
X do { f_mant_dig++; b=Mul(b, base); }
X while (Diff(Diff(Sum(b, ONE), b), ONE) == ZERO);
X f_dig=floor_log(10, (Long_double)(b/base)) + (base==10?1:0);
X Vprintf("%sSignificant base digits = %d %s %d %s%s\n",
X co, f_mant_dig, "(= at least", f_dig, "decimal digits)", oc);
X if (F) i_define(D_MANT_DIG, thing,
X Fname, "_MANT_DIG", (long) f_mant_dig,
X (long) F_MANT_DIG, "");
X if (F) i_define(D_DIG, thing,
X Fname, "_DIG", (long) f_dig, (long) F_DIG, "");
X digs= ceil_log(10, (Long_double)b); /* the number of digits to printf */
X
X /* Rounding *******************************************************/
X basem1=Diff(base, HALF);
X if (Diff(Sum(a, basem1), a) != ZERO) {
X if (f_radix == 2) basem1=0.375;
X else basem1=1.0;
X if (Diff(Sum(a, basem1), a) != ZERO) irnd=2; /* away from 0 */
X else irnd=1; /* to nearest */
X } else irnd=0; /* towards 0 */
X
X basem1=Diff(base, HALF);
X
X if (Diff(Diff(-a, basem1), -a) != ZERO) {
X if (f_radix == 2) basem1=0.375;
X else basem1=1.0;
X if (Diff(Diff(-a, basem1), -a) != ZERO) mrnd=2; /* away from 0*/
X else mrnd=1; /* to nearest */
X } else mrnd=0; /* towards 0 */
X
X f_rounds= -1; /* Unknown rounding */
X if (irnd==0 && mrnd==0) f_rounds=0; /* zero = chops */
X if (irnd==1 && mrnd==1) f_rounds=1; /* nearest */
X if (irnd==2 && mrnd==0) f_rounds=2; /* +inf */
X if (irnd==0 && mrnd==2) f_rounds=3; /* -inf */
X
X if (f_rounds != -1) {
X Vprintf("%sArithmetic rounds towards ", co);
X switch (f_rounds) {
X case 0: Vprintf("zero (i.e. it chops)"); break;
X case 1: Vprintf("nearest"); break;
X case 2: Vprintf("+infinity"); break;
X case 3: Vprintf("-infinity"); break;
X default: Vprintf("???"); break;
X }
X Vprintf("%s\n", oc);
X } else { /* Hmm, try to give some help here: */
X Vprintf("%sArithmetic rounds oddly: %s\n", co, oc);
X Vprintf("%s Negative numbers %s%s\n",
X co, mrnd==0 ? "towards zero" :
X mrnd==1 ? "to nearest" :
X "away from zero",
X oc);
X Vprintf("%s Positive numbers %s%s\n",
X co, irnd==0 ? "towards zero" :
X irnd==1 ? "to nearest" :
X "away from zero",
X oc);
X }
X /* An extra goody */
X if (f_radix == 2 && f_rounds == 1) {
X if (Diff(Sum(a, ONE), a) != ZERO) {
X Vprintf("%s Tie breaking rounds up%s\n", co, oc);
X } else if (Diff(Sum(a, THREE), a) == FOUR) {
X Vprintf("%s Tie breaking rounds to even%s\n", co, oc);
X } else {
X Vprintf("%s Tie breaking rounds down%s\n", co, oc);
X }
X }
X#ifdef PASS1 /* only for FLT */
X flt_rounds= f_rounds;
X if (F)
X i_define(D_FLT_ROUNDS, "",
X "FLT", "_ROUNDS", (long) f_rounds, (long) F_ROUNDS, "");
X#else
X if (f_rounds != flt_rounds) {
X printf("\n%s*** WARNING: %s %s (%d) %s%s\n",
X co, thing, "arithmetic rounds differently",
X f_rounds, "from float", oc);
X bugs++;
X }
X#endif
X
X /* Various flavours of epsilon ************************************/
X negeps=f_mant_dig+f_mant_dig;
X basein=1.0/base;
X a=1.0;
X for(i=1; i<=negeps; i++) a*=basein;
X
X b=a;
X while (Diff(Diff(ONE, a), ONE) == ZERO) {
X a*=base;
X negeps--;
X }
X negeps= -negeps;
X Vprintf("%sSmallest x such that 1.0-base**x != 1.0 = %d%s\n",
X co, negeps, oc);
X
X etop = ONE;
X ebot = ZERO;
X eps = Sum(ebot, Div(Diff(etop, ebot), TWO));
X while (eps != ebot && eps != etop) {
X epsp1 = Diff(ONE, eps);
X if (epsp1 < ONE) etop = eps;
X else ebot = eps;
X eps = Sum(ebot, Div(Diff(etop, ebot), TWO));
X }
X /* Sanity check */
X if (Diff(ONE, etop) >= ONE || Diff(ONE, ebot) != ONE) {
X eek_a_bug("internal error calculating epsneg");
X }
X Vprintf("%sSmallest x such that 1.0-x != 1.0 = %s%s\n",
X co, f_rep(digs, (Long_double) eps), oc);
X if (V) F_check(digs, (Long_double) eps);
X
X epsneg=a;
X if ((f_radix!=2) && irnd) {
X /* a=(a*(1.0+a))/(1.0+1.0); => */
X a=Div(Mul(a, Sum(ONE, a)), Sum(ONE, ONE));
X /* if ((1.0-a)-1.0 != 0.0) epsneg=a; => */
X if (Diff(Diff(ONE, a), ONE) != ZERO) epsneg=a;
X }
X /* epsneg is used later */
X Unexpected(20);
X
X machep= -f_mant_dig-f_mant_dig;
X a=b;
X while (Diff(Sum(ONE, a), ONE) == ZERO) { a*=base; machep++; }
X Vprintf("%sSmallest x such that 1.0+base**x != 1.0 = %d%s\n",
X co, machep, oc);
X
X etop = ONE;
X ebot = ZERO;
X eps = Sum(ebot, Div(Diff(etop, ebot), TWO));
X while (eps != ebot && eps != etop) {
X epsp1 = Sum(ONE, eps);
X if (epsp1 > ONE) etop = eps;
X else ebot = eps;
X eps = Sum(ebot, Div(Diff(etop, ebot), TWO));
X }
X /* Sanity check */
X if (Sum(ONE, etop) <= ONE || Sum(ONE, ebot) != ONE) {
X eek_a_bug("internal error calculating eps");
X }
X f_epsilon=etop;
X
X Vprintf("%sSmallest x such that 1.0+x != 1.0 = %s%s\n",
X co, f_rep(digs, (Long_double) f_epsilon), oc);
X /* Possible loss of precision warnings here from non-stdc compilers: */
X if (F) f_define(D_EPSILON, thing,
X Fname, "_EPSILON", digs, (Long_double) f_epsilon, MARK);
X if (V || F) F_check(digs, (Long_double) f_epsilon);
X Unexpected(21);
X if (F) Validate(digs, (Long_double) f_epsilon, (Long_double) F_EPSILON,
X f_epsilon == Self(F_EPSILON));
X Unexpected(22);
X
X /* Extra chop info *************************************************/
X if (f_rounds == 0) {
X if (Diff(Mul(Sum(ONE,f_epsilon),ONE),ONE) != ZERO) {
X Vprintf("%sAlthough arithmetic chops, it uses guard digits%s\n", co, oc);
X }
X }
X
X /* Size of and minimum normalised exponent ************************/
X y=0; i=0; k=1; z=basein; z1=(1.0+f_epsilon)/base;
X
X /* Coarse search for the largest power of two */
X if (setjmp(lab)==0) { /* for underflow trap */ /* Yields i, k, y, y1 */
X do {
X y=z; y1=z1;
X z=Mul(y,y); z1=Mul(z1, y);
X a=Mul(z,ONE);
X z2=Div(z1,y);
X if (z2 != y1) break;
X if ((Sum(a,a) == ZERO) || (fabs(z) >= y)) break;
X i++;
X k+=k;
X } while(1);
X } else {
X Vprintf("%s%s underflow generates a trap%s\n", co, Thing, oc);
X }
X Unexpected(23);
X
X if (f_radix != 10) {
X iexp=i+1; /* for the sign */
X mx=k+k;
X } else {
X iexp=2;
X iz=f_radix;
X while (k >= iz) { iz*=f_radix; iexp++; }
X mx=iz+iz-1;
X }
X
X /* Fine tune starting with y and y1 */
X if (setjmp(lab)==0) { /* for underflow trap */ /* Yields k, f_min */
X do {
X f_min=y; z1=y1;
X y=Div(y,base); y1=Div(y1,base);
X a=Mul(y,ONE);
X z2=Mul(y1,base);
X if (z2 != z1) break;
X if ((Sum(a,a) == ZERO) || (fabs(y) >= f_min)) break;
X k++;
X } while (1);
X }
X Unexpected(24);
X
X f_min_exp=(-k)+1;
X
X if ((mx <= k+k-3) && (f_radix != 10)) { mx+=mx; iexp+=1; }
X Vprintf("%sNumber of bits used for exponent = %d%s\n", co, iexp, oc);
X Vprintf("%sMinimum normalised exponent = %d%s\n", co, f_min_exp, oc);
X if (F)
X i_define(D_MIN_EXP, thing,
X Fname, "_MIN_EXP", (long) f_min_exp, (long) F_MIN_EXP, "");
X
X if (setjmp(lab)==0) {
X Vprintf("%sMinimum normalised positive number = %s%s\n",
X co, f_rep(digs, (Long_double) f_min), oc);
X } else {
X eek_a_bug("printf can't print the smallest normalised number");
X printf("\n");
X }
X Unexpected(25);
X /* Possible loss of precision warnings here from non-stdc compilers: */
X if (setjmp(lab) == 0) {
X if (F) f_define(D_MIN, thing,
X Fname, "_MIN", digs, (Long_double) f_min, MARK);
X if (V || F) F_check(digs, (Long_double) f_min);
X } else {
X eek_a_bug("xxx_MIN caused a trap");
X printf("\n");
X }
X
X if (setjmp(lab) == 0) {
X if (F) Validate(digs, (Long_double) f_min, (Long_double) F_MIN,
X f_min == Self(F_MIN));
X } else {
X printf("%s*** Verify failed for above #define!\n %s %s\n\n",
X co, "Compiler has an unusable number for value", oc);
X bugs++;
X }
X Unexpected(26);
X
X a=1.0; f_min_10_exp=0;
X while (a > f_min*10.0) { a/=10.0; f_min_10_exp--; }
X if (F) i_define(D_MIN_10_EXP, thing,
X Fname, "_MIN_10_EXP", (long) f_min_10_exp,
X (long) F_MIN_10_EXP, "");
X
X /* Minimum exponent ************************************************/
X if (setjmp(lab)==0) { /* for underflow trap */ /* Yields xminner */
X do {
X xminner=y;
X y=Div(y,base);
X a=Mul(y,ONE);
X if ((Sum(a,a) == ZERO) || (fabs(y) >= xminner)) break;
X } while (1);
X }
X Unexpected(27);
X
X if (xminner != 0.0 && xminner != f_min) {
X normal= 0;
X Vprintf("%sThe smallest numbers are not kept normalised%s\n",
X co, oc);
X if (setjmp(lab)==0) {
X Vprintf("%sSmallest unnormalised positive number = %s%s\n",
X co, f_rep(digs, (Long_double) xminner), oc);
X if (V) F_check(digs, (Long_double) xminner);
X } else {
X eek_a_bug("printf can't print the smallest unnormalised number.");
X printf("\n");
X }
X Unexpected(28);
X } else {
X normal= 1;
X Vprintf("%sThe smallest numbers are normalised%s\n", co, oc);
X }
X
X /* Maximum exponent ************************************************/
X f_max_exp=2; f_max=1.0; newxmax=base+1.0;
X inf=0; trap=0;
X while (f_max<newxmax) {
X f_max=newxmax;
X if (setjmp(lab) == 0) { /* Yields inf, f_max_exp */
X newxmax=Mul(newxmax, base);
X } else {
X trap=1;
X break;
X }
X if (Div(newxmax, base) != f_max) {
X inf=1; /* ieee infinity */
X break;
X }
X f_max_exp++;
X }
X Unexpected(29);
X if (trap) {
X Vprintf("%s%s overflow generates a trap%s\n", co, Thing, oc);
X }
X
X if (inf) Vprintf("%sThere is an 'infinite' value%s\n", co, oc);
X Vprintf("%sMaximum exponent = %d%s\n", co, f_max_exp, oc);
X if (F) i_define(D_MAX_EXP, thing,
X Fname, "_MAX_EXP", (long) f_max_exp,
X (long) F_MAX_EXP, "");
X
X /* Largest number ***************************************************/
X f_max=Diff(ONE, epsneg);
X if (Mul(f_max,ONE) != f_max) f_max=Diff(ONE, Mul(base,epsneg));
X for (i=1; i<=f_max_exp; i++) f_max=Mul(f_max, base);
X
X if (setjmp(lab)==0) {
X Vprintf("%sMaximum number = %s%s\n",
X co, f_rep(digs, (Long_double) f_max), oc);
X } else {
X eek_a_bug("printf can't print the largest double.");
X printf("\n");
X }
X if (setjmp(lab)==0) {
X /* Possible loss of precision warnings here from non-stdc compilers: */
X if (F) f_define(D_MAX, thing,
X Fname, "_MAX", digs, (Long_double) f_max, MARK);
X if (V || F) F_check(digs, (Long_double) f_max);
X } else {
X eek_a_bug("xxx_MAX caused a trap");
X printf("\n");
X }
X if (setjmp(lab)==0) {
X if (F) Validate(digs, (Long_double) f_max, (Long_double) F_MAX,
X f_max == Self(F_MAX));
X } else {
X printf("%s*** Verify failed for above #define!\n %s %s\n\n",
X co, "Compiler has an unusable number for value", oc);
X bugs++;
X }
X Unexpected(30);
X
X a=1.0; f_max_10_exp=0;
X while (a < f_max/10.0) { a*=10.0; f_max_10_exp++; }
X if (F) i_define(D_MAX_10_EXP, thing,
X Fname, "_MAX_10_EXP", (long) f_max_10_exp,
X (long) F_MAX_10_EXP, "");
X
X /* Hidden bit + sanity check ****************************************/
X if (f_radix != 10) {
X hidden=0;
X mantbits=floor_log(2, (Long_double)f_radix)*f_mant_dig;
X if (mantbits+iexp == (int)sizeof(Number)*bits_per_byte) {
X hidden=1;
X Vprintf("%sArithmetic uses a hidden bit%s\n", co, oc);
X } else if (mantbits+iexp+1 == (int)sizeof(Number)*bits_per_byte) {
X Vprintf("%sArithmetic doesn't use a hidden bit%s\n",
X co, oc);
X } else {
X printf("\n%s%s\n %s %s %s!%s\n\n",
X co,
X "*** Something fishy here!",
X "Exponent size + mantissa size doesn't match",
X "with the size of a", thing,
X oc);
X }
X if (hidden && f_radix == 2 && f_max_exp+f_min_exp==3) {
X Vprintf("%sIt looks like %s length IEEE format%s\n",
X co, f_mant_dig==24 ? "single" :
X f_mant_dig==53 ? "double" :
X f_mant_dig >53 ? "extended" :
X "some", oc);
X if (f_rounds != 1 || normal) {
X Vprintf("%s though ", co);
X if (f_rounds != 1) {
X Vprintf("the rounding is unusual");
X if (normal) Vprintf(" and ");
X }
X if (normal) Vprintf("the normalisation is unusual");
X Vprintf("%s\n", oc);
X }
X } else {
X Vprintf("%sIt doesn't look like IEEE format%s\n",
X co, oc);
X }
X }
X printf("\n"); /* regardless of verbosity */
X return f_mant_dig;
X}
X
XProcedure EPROP(fprec, dprec, lprec) int fprec, dprec, lprec; {
X /* See if expressions are evaluated in extended precision.
X Some compilers optimise even if you don't want it,
X and then this function fails to produce the right result.
X We try to diagnose this if it happens.
X */
X Volatile int eprec;
X Volatile double a, b, base, old;
X Volatile Number d, oldd, dbase, one, zero;
X Volatile int bad=0;
X
X /* Size of mantissa **************************************/
X a=1.0;
X if (setjmp(lab) == 0) { /* Yields nothing */
X do { old=a; a=a+a; }
X while ((((a+1.0)-a)-1.0) == 0.0 && a>old);
X } else bad=1;
X if (a <= old) bad=1;
X
X if (!bad) {
X b=1.0;
X if (setjmp(lab) == 0) { /* Yields nothing */
X do { old=b; b=b+b; }
X while ((base=((a+b)-a)) == 0.0 && b>old);
X if (b <= old) bad=1;
X } else bad=1;
X }
X
X if (!bad) {
X eprec=0; d=1.0; dbase=base; one=1.0; zero=0.0;
X if (setjmp(lab) == 0) { /* Yields nothing */
X do { eprec++; oldd=d; d=d*dbase; }
X while ((((d+one)-d)-one) == zero && d>oldd);
X if (d <= oldd) bad=1;
X } else bad=1;
X }
X
X Unexpected(31);
X
X if (bad) {
X Vprintf("%sCan't determine precision for %s expressions:\n%s%s\n",
X co, thing, " check that you compiled without optimisation!",
X oc);
X } else if (eprec==dprec) {
X Vprintf("%s%s expressions are evaluated in double precision%s\n",
X co, Thing, oc);
X } else if (eprec==fprec) {
X Vprintf("%s%s expressions are evaluated in float precision%s\n",
X co, Thing, oc);
X } else if (eprec==lprec) {
X Vprintf("%s%s expressions are evaluated in long double precision%s\n",
X co, Thing, oc);
X } else {
X Vprintf("%s%s expressions are evaluated in a %s %s %d %s%s\n",
X co, Thing, eprec>dprec ? "higher" : "lower",
X "precision than double,\n using",
X eprec, "base digits",
X oc);
X }
X}
X
X#else /* not Number */
X
X#ifdef FPROP
X/* ARGSUSED */
Xint FPROP(bits_per_byte) int bits_per_byte; { return 0; }
X#endif
X#ifdef EPROP
X/* ARGSUSED */
XProcedure EPROP(fprec, dprec, lprec) int fprec, dprec, lprec; {}
X#endif
X
X#endif /* ifdef Number */
X
X#ifdef PASS3
X#undef PASS
X#endif
X
X#ifdef PASS2
X#undef PASS2
X#define PASS3 1
X#endif
X
X#ifdef PASS1
X#undef PASS1
X#define PASS2 1
X#endif
X
X#ifdef PASS0
X#undef PASS0
X#endif
X
X#ifdef PASS /* then rescan this file */
X#ifdef NO_FILE
X#include "config.c"
X#else /* if the next line fails to compile, define NO_FILE */
X#include __FILE__
X#endif
X#endif /* PASS */
EOF
fi
echo 'Part 01 out of 01 of pack.out complete.'
exit 0
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