usr/src/sys/tahoe/align/align.c

/*      align.c 1.1     86/07/20        */

#include        "../tahoealign/align.h"

/*
 * Part of the parameter list is set up by locore.s.
 * First 2 dummy variables MUST BE the first local
 * variables; leaving place for registers 0 and 1
 * which are not preserved by the current C compiler.
 * Then, the array of structures and the last_operand
 * HAVE to be in the given order, to correspond to the
 * description of process_info in 'alignment.h'.
 */
alignment()
{
        long    space_4_Register_1;     /* register 1 */
        long    space_4_Register_0;     /* register 0 */
        struct  oprnd   space_4_decoded[4];
        long    space_4_opcode;
        long    space_4_last_operand;   /* Last operand # processed */
        long    space_4_saved_pc;
        long    space_4_saved_sp;

        register process_info *infop;

        infop = (process_info *)&space_4_saved_sp;
        saved_pc = pc;
        saved_sp = sp;                          /* For possible exceptions */

        last_operand = -1;   /* To get the operand routine going correctly */

        opCODE = 0xff & *(char *)pc;
        pc++;
        (*Table[opCODE].routine) (infop);       /* Call relevant handler */
        /*
         * NOTE: nothing should follow, except the return.
         * The register variables cannot be trusted anymore,
         * if an exception is signalled.  See 'exception.c'
         * to understand why.
         */
}