36 lines
		
	
	
		
			571 B
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			36 lines
		
	
	
		
			571 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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	.file	"ilogbf.S"
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	.text
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	.align 4
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.globl _ilogbf
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	.def	_ilogbf;	.scl	2;	.type	32;	.endef
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_ilogbf:
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	flds	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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