xref: /csrg-svn/sys/tahoe/align/align.c (revision 29646)
1*29646Ssam /*	align.c	1.1	86/07/20	*/
2*29646Ssam 
3*29646Ssam #include	"../tahoealign/align.h"
4*29646Ssam 
5*29646Ssam /*
6*29646Ssam  * Part of the parameter list is set up by locore.s.
7*29646Ssam  * First 2 dummy variables MUST BE the first local
8*29646Ssam  * variables; leaving place for registers 0 and 1
9*29646Ssam  * which are not preserved by the current C compiler.
10*29646Ssam  * Then, the array of structures and the last_operand
11*29646Ssam  * HAVE to be in the given order, to correspond to the
12*29646Ssam  * description of process_info in 'alignment.h'.
13*29646Ssam  */
14*29646Ssam alignment()
15*29646Ssam {
16*29646Ssam 	long	space_4_Register_1;	/* register 1 */
17*29646Ssam 	long	space_4_Register_0;	/* register 0 */
18*29646Ssam 	struct	oprnd	space_4_decoded[4];
19*29646Ssam 	long	space_4_opcode;
20*29646Ssam 	long	space_4_last_operand;	/* Last operand # processed */
21*29646Ssam 	long	space_4_saved_pc;
22*29646Ssam 	long	space_4_saved_sp;
23*29646Ssam 
24*29646Ssam 	register process_info *infop;
25*29646Ssam 
26*29646Ssam 	infop = (process_info *)&space_4_saved_sp;
27*29646Ssam 	saved_pc = pc;
28*29646Ssam 	saved_sp = sp;	     			/* For possible exceptions */
29*29646Ssam 
30*29646Ssam 	last_operand = -1;   /* To get the operand routine going correctly */
31*29646Ssam 
32*29646Ssam 	opCODE = 0xff & *(char *)pc;
33*29646Ssam 	pc++;
34*29646Ssam 	(*Table[opCODE].routine) (infop);	/* Call relevant handler */
35*29646Ssam 	/*
36*29646Ssam 	 * NOTE: nothing should follow, except the return.
37*29646Ssam 	 * The register variables cannot be trusted anymore,
38*29646Ssam 	 * if an exception is signalled.  See 'exception.c'
39*29646Ssam 	 * to understand why.
40*29646Ssam 	 */
41*29646Ssam }
42