gcc/libgcc/config/i386/sfp-machine.h
Joseph Myers e770bfd997 Fix i386 FP_TRAPPING_EXCEPTIONS.
The i386 sfp-machine.h defines FP_TRAPPING_EXCEPTIONS in a way that is
always wrong: it treats a set bit as indicating the exception is
trapping, when actually a set bit (both for 387 and SSE floating
point) indicates it is masked, and a clear bit indicates it is
trapping.  This patch fixes this bug.

Bootstrapped with no regressions on x86_64-unknown-linux-gnu.

libgcc:
	* config/i386/sfp-machine.h (FP_TRAPPING_EXCEPTIONS): Treat clear
	bits not set bits as indicating trapping exceptions.

gcc/testsuite:
	* gcc.dg/torture/float128-exact-underflow.c: New test.

From-SVN: r215347
2014-09-18 13:00:21 +01:00

86 lines
2.4 KiB
C

#ifdef __MINGW32__
/* Make sure we are using gnu-style bitfield handling. */
#define _FP_STRUCT_LAYOUT __attribute__ ((gcc_struct))
#endif
/* The type of the result of a floating point comparison. This must
match `__libgcc_cmp_return__' in GCC for the target. */
typedef int __gcc_CMPtype __attribute__ ((mode (__libgcc_cmp_return__)));
#define CMPtype __gcc_CMPtype
#ifdef __x86_64__
#include "config/i386/64/sfp-machine.h"
#else
#include "config/i386/32/sfp-machine.h"
#endif
#define _FP_KEEPNANFRACP 1
#define _FP_QNANNEGATEDP 0
#define _FP_NANSIGN_S 1
#define _FP_NANSIGN_D 1
#define _FP_NANSIGN_E 1
#define _FP_NANSIGN_Q 1
/* Here is something Intel misdesigned: the specs don't define
the case where we have two NaNs with same mantissas, but
different sign. Different operations pick up different NaNs. */
#define _FP_CHOOSENAN(fs, wc, R, X, Y, OP) \
do { \
if (_FP_FRAC_GT_##wc(X, Y) \
|| (_FP_FRAC_EQ_##wc(X,Y) && (OP == '+' || OP == '*'))) \
{ \
R##_s = X##_s; \
_FP_FRAC_COPY_##wc(R,X); \
} \
else \
{ \
R##_s = Y##_s; \
_FP_FRAC_COPY_##wc(R,Y); \
} \
R##_c = FP_CLS_NAN; \
} while (0)
#ifndef _SOFT_FLOAT
#define FP_EX_INVALID 0x01
#define FP_EX_DENORM 0x02
#define FP_EX_DIVZERO 0x04
#define FP_EX_OVERFLOW 0x08
#define FP_EX_UNDERFLOW 0x10
#define FP_EX_INEXACT 0x20
#define FP_EX_ALL \
(FP_EX_INVALID | FP_EX_DENORM | FP_EX_DIVZERO | FP_EX_OVERFLOW \
| FP_EX_UNDERFLOW | FP_EX_INEXACT)
void __sfp_handle_exceptions (int);
#define FP_HANDLE_EXCEPTIONS \
do { \
if (__builtin_expect (_fex, 0)) \
__sfp_handle_exceptions (_fex); \
} while (0);
#define FP_TRAPPING_EXCEPTIONS ((~_fcw >> FP_EX_SHIFT) & FP_EX_ALL)
#define FP_ROUNDMODE (_fcw & FP_RND_MASK)
#endif
#define _FP_TININESS_AFTER_ROUNDING 1
#define __LITTLE_ENDIAN 1234
#define __BIG_ENDIAN 4321
#define __BYTE_ORDER __LITTLE_ENDIAN
/* Define ALIASNAME as a strong alias for NAME. */
#if defined __MACH__
/* Mach-O doesn't support aliasing. If these functions ever return
anything but CMPtype we need to revisit this... */
#define strong_alias(name, aliasname) \
CMPtype aliasname (TFtype a, TFtype b) { return name(a, b); }
#else
# define strong_alias(name, aliasname) _strong_alias(name, aliasname)
# define _strong_alias(name, aliasname) \
extern __typeof (name) aliasname __attribute__ ((alias (#name)));
#endif