jscpucfg.cpp
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla Communicator client code, released
* March 31, 1998.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Roland Mainz <roland.mainz@informatik.med.uni-giessen.de>
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
/*
* Generate CPU-specific bit-size and similar #defines.
*/
#include <stdio.h>
#include <stdlib.h>
#if defined(CROSS_COMPILE) && !defined(FORCE_BIG_ENDIAN) && !defined(FORCE_LITTLE_ENDIAN)
#include <prtypes.h>
#endif
/************************************************************************/
int main(int argc, char **argv)
{
printf("#ifndef js_cpucfg___\n");
printf("#define js_cpucfg___\n\n");
printf("/* AUTOMATICALLY GENERATED - DO NOT EDIT */\n\n");
#ifdef CROSS_COMPILE
#if defined(__APPLE__) && !defined(FORCE_BIG_ENDIAN) && !defined(FORCE_LITTLE_ENDIAN)
/*
* Darwin NSPR uses the same MDCPUCFG (_darwin.cfg) for multiple
* processors, and determines which processor to configure for based
* on compiler predefined macros. We do the same thing here.
*/
printf("#ifdef __LITTLE_ENDIAN__\n");
printf("#define IS_LITTLE_ENDIAN 1\n");
printf("#undef IS_BIG_ENDIAN\n");
printf("#else\n");
printf("#undef IS_LITTLE_ENDIAN\n");
printf("#define IS_BIG_ENDIAN 1\n");
printf("#endif\n\n");
#elif defined(IS_LITTLE_ENDIAN) || defined(FORCE_LITTLE_ENDIAN)
printf("#define IS_LITTLE_ENDIAN 1\n");
printf("#undef IS_BIG_ENDIAN\n\n");
#elif defined(IS_BIG_ENDIAN) || defined(FORCE_BIG_ENDIAN)
printf("#undef IS_LITTLE_ENDIAN\n");
printf("#define IS_BIG_ENDIAN 1\n\n");
#else
#error "Endianess not defined."
#endif
#else
/*
* We don't handle PDP-endian or similar orders: if a short is big-endian,
* so must int and long be big-endian for us to generate the IS_BIG_ENDIAN
* #define and the IS_LITTLE_ENDIAN #undef.
*/
{
int big_endian = 0, little_endian = 0, ntests = 0;
if (sizeof(short) == 2) {
/* force |volatile| here to get rid of any compiler optimisations
* (var in register etc.) which may be appiled to |auto| vars -
* even those in |union|s...
* (|static| is used to get the same functionality for compilers
* which do not honor |volatile|...).
*/
volatile static union {
short i;
char c[2];
} u;
u.i = 0x0102;
big_endian += (u.c[0] == 0x01 && u.c[1] == 0x02);
little_endian += (u.c[0] == 0x02 && u.c[1] == 0x01);
ntests++;
}
if (sizeof(int) == 4) {
/* force |volatile| here ... */
volatile static union {
int i;
char c[4];
} u;
u.i = 0x01020304;
big_endian += (u.c[0] == 0x01 && u.c[1] == 0x02 &&
u.c[2] == 0x03 && u.c[3] == 0x04);
little_endian += (u.c[0] == 0x04 && u.c[1] == 0x03 &&
u.c[2] == 0x02 && u.c[3] == 0x01);
ntests++;
}
if (sizeof(long) == 8) {
/* force |volatile| here ... */
volatile static union {
long i;
char c[8];
} u;
/*
* Write this as portably as possible: avoid 0x0102030405060708L
* and <<= 32.
*/
u.i = 0x01020304;
u.i <<= 16, u.i <<= 16;
u.i |= 0x05060708;
big_endian += (u.c[0] == 0x01 && u.c[1] == 0x02 &&
u.c[2] == 0x03 && u.c[3] == 0x04 &&
u.c[4] == 0x05 && u.c[5] == 0x06 &&
u.c[6] == 0x07 && u.c[7] == 0x08);
little_endian += (u.c[0] == 0x08 && u.c[1] == 0x07 &&
u.c[2] == 0x06 && u.c[3] == 0x05 &&
u.c[4] == 0x04 && u.c[5] == 0x03 &&
u.c[6] == 0x02 && u.c[7] == 0x01);
ntests++;
}
if (big_endian && big_endian == ntests) {
printf("#undef IS_LITTLE_ENDIAN\n");
printf("#define IS_BIG_ENDIAN 1\n\n");
} else if (little_endian && little_endian == ntests) {
printf("#define IS_LITTLE_ENDIAN 1\n");
printf("#undef IS_BIG_ENDIAN\n\n");
} else {
fprintf(stderr, "%s: unknown byte order"
"(big_endian=%d, little_endian=%d, ntests=%d)!\n",
argv[0], big_endian, little_endian, ntests);
return EXIT_FAILURE;
}
}
#endif /* CROSS_COMPILE */
// PA-RISC is the only platform we try to support on which the stack
// grows towards higher addresses. Trying to detect it here has
// historically led to portability problems, which aren't worth it
// given the near consensus on stack growth direction.
printf("#ifdef __hppa\n"
"# define JS_STACK_GROWTH_DIRECTION (1)\n"
"#else\n"
"# define JS_STACK_GROWTH_DIRECTION (-1)\n"
"#endif\n");
printf("#endif /* js_cpucfg___ */\n");
return EXIT_SUCCESS;
}