| /* |
| * Written by J.T. Conklin <jtc@netbsd.org>. |
| * Changes for long double by Ulrich Drepper <drepper@cygnus.com> |
| * Adapted for x86-64 by Andreas Jaeger <aj@suse.de>. |
| * Public domain. |
| */ |
| |
| #include <machine/asm.h> |
| |
| ENTRY(__ieee754_ilogbl) |
| fldt 8(%rsp) |
| /* I added the following ugly construct because ilogb(+-Inf) is |
| required to return INT_MAX in ISO C99. |
| -- jakub@redhat.com. */ |
| fxam /* Is NaN or +-Inf? */ |
| fstsw %ax |
| movb $0x45, %dh |
| andb %ah, %dh |
| cmpb $0x05, %dh |
| je 1f /* Is +-Inf, jump. */ |
| cmpb $0x40, %dh |
| je 2f /* Is +-Inf, jump. */ |
| |
| fxtract |
| fstp %st |
| |
| fistpl -4(%rsp) |
| fwait |
| movl -4(%rsp),%eax |
| |
| ret |
| |
| 1: fstp %st |
| movl $0x7fffffff, %eax |
| ret |
| 2: fstp %st |
| movl $0x80000000, %eax /* FP_ILOGB0 */ |
| ret |
| END (__ieee754_ilogbl) |
