yann@402: Taken from http://sources.redhat.com/ml/crossgcc/2004-02/msg00104.html yann@402: Author: addsub@eyou.com yann@402: Target: ARM yann@402: yann@402: Fixes http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/gcc.c-torture/execute/920501-8.c yann@402: and makes printf("%f", 1.0) work. yann@402: yann@402: Lennert Buytenhek wrote in http://sources.redhat.com/ml/crossgcc/2004-09/msg00115.html : yann@402: It ... fixes the 'printf("%f\n", 0.5); prints 0.000000' and general 'floating point yann@402: is broken' on my big-endian hardfloat FPA ARM platform. ... yann@402: It's definitely needed for hardfloat. So I'd think it's needed for yann@402: big-endian systems in any case, and for VFP on little-endian systems yann@402: too. Someone would have to verify that though. yann@402: yann@402: Lennert Buytenhek wrote in http://sources.redhat.com/ml/crossgcc/2004-09/msg00123.html yann@402: I just had a look at glibc-20040830, and [this patch] is still needed and useful yann@402: for this version. glibc-20040830 out-of-the-box still contains the yann@402: following wrong assumptions: yann@402: - sysdeps/arm/bits/endian.h: float word order is big endian (which it is yann@402: not on vfp systems) yann@402: - sysdeps/arm/gmp-mparam.h: IEEE doubles are mixed endian (which they yann@402: are not on big endian systems, neither on vfp systems) yann@402: - sysdeps/arm/ieee754.h: IEEE doubles are in little endian byte order yann@402: (which they are not on big endian systems) yann@402: [This patch] seems the right solution for all of these issues. yann@402: yann@402: Dimitry Andric wrote in http://sources.redhat.com/ml/crossgcc/2004-09/msg00132.html : yann@402: It's even needed for glibc CVS, AFAICS. yann@402: The patch hunk which modifies glibc.new/sysdeps/arm/bits/endian.h yann@402: (currently at version 1.4) is only needed for proper VFP operation. yann@402: But the hunk which modifies sysdeps/arm/gmp-mparam.h, and the hunk yann@402: that deletes sysdeps/arm/ieee754.h (yes, this IS correct), are needed yann@402: for proper operation of *any* FP model on big endian ARM. yann@402: yann@402: See also discussion in followups to yann@402: http://sources.redhat.com/ml/crossgcc/2004-05/msg00245.html) yann@402: yann@402: Message-ID: <276985760.37584@eyou.com> yann@402: Received: from unknown (HELO eyou.com) (172.16.2.2) yann@402: by 0.0.0.0 with SMTP; Tue, 17 Feb 2004 10:42:40 +0800 yann@402: Received: (qmail 8238 invoked by uid 65534); 17 Feb 2004 10:42:38 +0800 yann@402: Date: 17 Feb 2004 10:42:38 +0800 yann@402: Message-ID: <20040217104238.8237.qmail@eyou.com> yann@402: From: "add" yann@402: To: dank@kegel.com yann@402: Reply-To: "add" yann@402: Subject: Re:   problem while building arm vfp softfloat gcc ` yann@402: yann@402: Hi, Dan, This is a patch I applied to my glibc-2.3.2, then my softfloat yann@402: toolchain can printf("%f\n",1.0). So you may have a try of this yann@402: yann@402: yann@402: diff -uNrp glibc.old/sysdeps/arm/bits/endian.h glibc.new/sysdeps/arm/bits/endian.h yann@402: --- glibc.old/sysdeps/arm/bits/endian.h 1999-04-12 11:59:13.000000000 -0400 yann@402: +++ glibc.new/sysdeps/arm/bits/endian.h 2004-02-12 09:15:13.000000000 -0500 yann@402: @@ -9,4 +9,9 @@ yann@402: #else yann@402: #define __BYTE_ORDER __LITTLE_ENDIAN yann@402: #endif yann@402: + yann@402: +#ifdef __VFP_FP__ yann@402: +#define __FLOAT_WORD_ORDER __BYTE_ORDER yann@402: +#else yann@402: #define __FLOAT_WORD_ORDER __BIG_ENDIAN yann@402: +#endif yann@402: diff -uNrp glibc.old/sysdeps/arm/gmp-mparam.h glibc.new/sysdeps/arm/gmp-mparam.h yann@402: --- glibc.old/sysdeps/arm/gmp-mparam.h 2001-07-07 15:21:19.000000000 -0400 yann@402: +++ glibc.new/sysdeps/arm/gmp-mparam.h 2004-02-12 09:15:13.000000000 -0500 yann@402: @@ -26,5 +26,13 @@ MA 02111-1307, USA. */ yann@402: #define BITS_PER_SHORTINT 16 yann@402: #define BITS_PER_CHAR 8 yann@402: yann@402: -#define IEEE_DOUBLE_BIG_ENDIAN 0 yann@402: -#define IEEE_DOUBLE_MIXED_ENDIAN 1 yann@402: +#if defined(__ARMEB__) yann@402: +# define IEEE_DOUBLE_MIXED_ENDIAN 0 yann@402: +# define IEEE_DOUBLE_BIG_ENDIAN 1 yann@402: +#elif defined(__VFP_FP__) yann@402: +# define IEEE_DOUBLE_MIXED_ENDIAN 0 yann@402: +# define IEEE_DOUBLE_BIG_ENDIAN 0 yann@402: +#else yann@402: +# define IEEE_DOUBLE_BIG_ENDIAN 0 yann@402: +# define IEEE_DOUBLE_MIXED_ENDIAN 1 yann@402: +#endif yann@402: diff -uNrp glibc.old/sysdeps/arm/ieee754.h glibc.new/sysdeps/arm/ieee754.h yann@402: --- glibc.old/sysdeps/arm/ieee754.h 2001-07-07 15:21:19.000000000 -0400 yann@402: +++ glibc.new/sysdeps/arm/ieee754.h 1969-12-31 19:00:00.000000000 -0500 yann@402: @@ -1,115 +0,0 @@ yann@402: -/* Copyright (C) 1992, 1995, 1996, 1998 Free Software Foundation, Inc. yann@402: - This file is part of the GNU C Library. yann@402: - yann@402: - The GNU C Library is free software; you can redistribute it and/or yann@402: - modify it under the terms of the GNU Lesser General Public yann@402: - License as published by the Free Software Foundation; either yann@402: - version 2.1 of the License, or (at your option) any later version. yann@402: - yann@402: - The GNU C Library is distributed in the hope that it will be useful, yann@402: - but WITHOUT ANY WARRANTY; without even the implied warranty of yann@402: - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU yann@402: - Lesser General Public License for more details. yann@402: - yann@402: - You should have received a copy of the GNU Lesser General Public yann@402: - License along with the GNU C Library; if not, write to the Free yann@402: - Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA yann@402: - 02111-1307 USA. */ yann@402: - yann@402: -#ifndef _IEEE754_H yann@402: - yann@402: -#define _IEEE754_H 1 yann@402: -#include yann@402: - yann@402: -#include yann@402: - yann@402: -__BEGIN_DECLS yann@402: - yann@402: -union ieee754_float yann@402: - { yann@402: - float f; yann@402: - yann@402: - /* This is the IEEE 754 single-precision format. */ yann@402: - struct yann@402: - { yann@402: - unsigned int mantissa:23; yann@402: - unsigned int exponent:8; yann@402: - unsigned int negative:1; yann@402: - } ieee; yann@402: - yann@402: - /* This format makes it easier to see if a NaN is a signalling NaN. */ yann@402: - struct yann@402: - { yann@402: - unsigned int mantissa:22; yann@402: - unsigned int quiet_nan:1; yann@402: - unsigned int exponent:8; yann@402: - unsigned int negative:1; yann@402: - } ieee_nan; yann@402: - }; yann@402: - yann@402: -#define IEEE754_FLOAT_BIAS 0x7f /* Added to exponent. */ yann@402: - yann@402: - yann@402: -union ieee754_double yann@402: - { yann@402: - double d; yann@402: - yann@402: - /* This is the IEEE 754 double-precision format. */ yann@402: - struct yann@402: - { yann@402: - unsigned int mantissa0:20; yann@402: - unsigned int exponent:11; yann@402: - unsigned int negative:1; yann@402: - unsigned int mantissa1:32; yann@402: - } ieee; yann@402: - yann@402: - /* This format makes it easier to see if a NaN is a signalling NaN. */ yann@402: - struct yann@402: - { yann@402: - unsigned int mantissa0:19; yann@402: - unsigned int quiet_nan:1; yann@402: - unsigned int exponent:11; yann@402: - unsigned int negative:1; yann@402: - unsigned int mantissa1:32; yann@402: - } ieee_nan; yann@402: - }; yann@402: - yann@402: -#define IEEE754_DOUBLE_BIAS 0x3ff /* Added to exponent. */ yann@402: - yann@402: - yann@402: -/* The following two structures are correct for `new' floating point systems but yann@402: - wrong for the old FPPC. The only solution seems to be to avoid their use on yann@402: - old hardware. */ yann@402: - yann@402: -union ieee854_long_double yann@402: - { yann@402: - long double d; yann@402: - yann@402: - /* This is the IEEE 854 double-extended-precision format. */ yann@402: - struct yann@402: - { yann@402: - unsigned int exponent:15; yann@402: - unsigned int empty:16; yann@402: - unsigned int negative:1; yann@402: - unsigned int mantissa1:32; yann@402: - unsigned int mantissa0:32; yann@402: - } ieee; yann@402: - yann@402: - /* This is for NaNs in the IEEE 854 double-extended-precision format. */ yann@402: - struct yann@402: - { yann@402: - unsigned int exponent:15; yann@402: - unsigned int empty:16; yann@402: - unsigned int negative:1; yann@402: - unsigned int mantissa1:32; yann@402: - unsigned int mantissa0:30; yann@402: - unsigned int quiet_nan:1; yann@402: - unsigned int one:1; yann@402: - } ieee_nan; yann@402: - }; yann@402: - yann@402: -#define IEEE854_LONG_DOUBLE_BIAS 0x3fff yann@402: - yann@402: -__END_DECLS yann@402: - yann@402: -#endif /* ieee754.h */ yann@402: yann@402: Signed-off-by: Robert P. J. Day