xref: /csrg-svn/sys/tahoe/align/Aadwc.c (revision 45699)
1*45699Sbostic /*	Aadwc.c	1.2	90/12/04	*/
229586Ssam 
3*45699Sbostic #include "align.h"
429586Ssam adwc(infop)	process_info *infop;
529586Ssam /*
629586Ssam /*	Add with carry.
729586Ssam /*	Note : the play with 'tmp' just before the 'asm' line makes
829586Ssam /*		sure that when the adwc opcode is executed, the current
929586Ssam /*		carry in psl is the same as the 'offending' process'.
1029586Ssam /*		Don't change unless you know exactly what you're doing.
1129586Ssam /*
1229586Ssam /*****************************/
1329586Ssam {
1429586Ssam 	register	long	Register_12;	/* Has to be first reg ! */
1529586Ssam 	register	long	Register_11;
1629586Ssam 	register	long	Register_10;
1729586Ssam 	register 	long	tmp;
1829586Ssam 
1929586Ssam 	Register_12 = operand(infop,0)->data;
2029586Ssam 	Register_11 = operand(infop,1)->data;
2129586Ssam 	if (carry)	/* If process' carry set */
2229586Ssam 		tmp = -1;
2329586Ssam 	else tmp = 0;
2429586Ssam 	tmp++;		/* 0 => carry set.  1 => carry clear */
2529586Ssam 
2629586Ssam 	Register_10=psl;
2729586Ssam 	Set_psl(r10);	/* restore the user psl */
2829586Ssam 	asm("	adwc	r11,r12");
2929586Ssam 	asm("	movpsl	r11");
3029586Ssam 	New_cc (Register_11);
3129586Ssam 
3229586Ssam 	write_back(infop, Register_12, operand(infop,1) );
3329586Ssam }
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