usr/src/cmd/adb/findfn.c

#
/*
 *
 *      UNIX debugger
 *
 */

#include "defs.h"


MSG             NOCFN;

INT             callpc;
BOOL            localok;
SYMTAB          symbol;

STRING          errflg;


findroutine(cframe)
        L_INT           cframe;
{
        REG INT         narg, inst;
        INT             lastpc, back2;
        BOOL            v;

        v=FALSE; localok=FALSE; lastpc=callpc;
        callpc=get(cframe+2, DSP); back2=get(leng(callpc-2), ISP);
        IF (inst=get(leng(callpc-4), ISP)) == 04737     /* jsr pc,*$... */
        THEN    narg = 1;
        ELIF (inst&~077)==04700                 /* jsr pc,... */
        THEN    narg=0; v=(inst!=04767);
        ELIF (back2&~077)==04700
        THEN    narg=0; v=TRUE;
        ELSE    errflg=NOCFN;
                return(0);
        FI
        IF findsym( (v ? lastpc : ((inst==04767?callpc:0) + back2) ),ISYM) == -1
            ANDF !v
        THEN    symbol.symc[0] = '?';
                symbol.symc[1] = 0;
                symbol.symv = 0;
        ELSE    localok=TRUE;
        FI
        inst = get(leng(callpc), ISP);
        IF inst == 05726                /* tst (sp)+ */
        THEN    return(narg+1);
        FI
        IF inst == 022626               /* cmp (sp)+,(sp)+ */
        THEN    return(narg+2);
        FI
        IF inst == 062706               /* add $n,sp */
        THEN    return(narg+get(leng(callpc+2), ISP)/2);
        FI
        return(narg);
}