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26 7u83 1 
/*
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 *	mpvecdigmul(mpdigit *b, int n, mpdigit m, mpdigit *p)
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 *
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 *	p += b*m
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 *
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 *	each step look like:
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 *		hi,lo = m*b[i]
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 *		lo += oldhi + carry
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 *		hi += carry
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 *		p[i] += lo
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 *		oldhi = hi
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 *
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 *	the registers are:
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 *		hi = DX		- constrained by hardware
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 *		lo = AX		- constrained by hardware
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 *		b+n = SI	- can't be BP
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 *		p+n = DI	- can't be BP
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 *		i-n = BP
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 *		m = BX
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 *		oldhi = CX
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 *
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 */
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TEXT	mpvecdigmuladd(SB),$0
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	MOVQ	RARG,SI
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	MOVL	n+8(FP),CX
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	MOVL	m+16(FP),BX
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	MOVQ	p+24(FP),DI
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	MOVL	CX,BP
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	NEGQ	BP		/* BP = -n */
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	SHLL	$2,CX
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	ADDQ	CX,SI		/* SI = b + n */
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	ADDQ	CX,DI		/* DI = p + n */
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	XORL	CX,CX
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_muladdloop:
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	MOVL	(SI)(BP*4),AX	/* lo = b[i] */
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	MULL	BX		/* hi, lo = b[i] * m */
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	ADDL	CX,AX		/* lo += oldhi */
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	ADCL	$0, DX		/* hi += carry */
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	ADDL	AX,(DI)(BP*4)	/* p[i] += lo */
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	ADCL	$0, DX		/* hi += carry */
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	MOVL	DX,CX		/* oldhi = hi */
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	INCQ	BP		/* i++ */
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	JNZ	_muladdloop
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	XORL	AX,AX
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	ADDL	CX,(DI)(BP*4)	/* p[n] + oldhi */
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	ADCL	AX,AX		/* return carry out of p[n] */
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	RET