blob: 5dc36dc2eb909598f6b112a0aedef9c0c50fe7b8 [file] [log] [blame]
/**
* This file has no copyright assigned and is placed in the Public Domain.
* This file is part of the w64 mingw-runtime package.
* No warranty is given; refer to the file DISCLAIMER within this package.
*/
#ifdef _WIN64
.file "ilogb.S"
.text
.align 8
.globl _ilogb
.def _ilogb; .scl 2; .type 32; .endef
_ilogb:
movsd %xmm0,-16(%rsp)
fldl -16(%rsp)
fxam /* Is NaN or +-Inf? */
fstsw %ax
movb $0x45, %dh
andb %ah, %dh
cmpb $0x05, %dh
je 1f /* Is +-Inf, jump. */
fxtract
pushq %rax
fstp %st
fistpl (%rsp)
fwait
popq %rax
ret
1: fstp %st
movl $0x7fffffff, %eax
ret
#else
.file "ilogb.S"
.text
.align 4
.globl _ilogb
.def _ilogb; .scl 2; .type 32; .endef
_ilogb:
fldl 4(%esp)
/* 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. */
fxtract
pushl %eax
fstp %st
fistpl (%esp)
fwait
popl %eax
ret
1: fstp %st
movl $0x7fffffff, %eax
ret
#endif