37 lines
620 B
ArmAsm
37 lines
620 B
ArmAsm
/*
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* Written by J.T. Conklin <jtc@netbsd.org>.
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* Public domain.
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*/
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#include <machine/asm.h>
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RCSID("$NetBSD: s_ilogb.S,v 1.5 1995/10/12 15:53:09 jtc Exp $")
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ENTRY(__ilogb)
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fldl 4(%esp)
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/* I added the following ugly construct because ilogb(+-Inf) is
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required to return INT_MAX in ISO C99.
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-- jakub@redhat.com. */
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fxam /* Is NaN or +-Inf? */
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fstsw %ax
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movb $0x45, %dh
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andb %ah, %dh
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cmpb $0x05, %dh
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je 1f /* Is +-Inf, jump. */
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fxtract
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pushl %eax
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fstp %st
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fistpl (%esp)
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fwait
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popl %eax
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ret
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1: fstp %st
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movl $0x7fffffff, %eax
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ret
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END (__ilogb)
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weak_alias (__ilogb, ilogb)
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