/*
 * Copyright (c) 1983 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that: (1) source distributions retain this entire copyright
 * notice and comment, and (2) distributions including binaries display
 * the following acknowledgement:  ``This product includes software
 * developed by the University of California, Berkeley and its contributors''
 * in the documentation or other materials provided with the distribution
 * and in all advertising materials mentioning features or use of this
 * software. Neither the name of the University nor the names of its
 * contributors may be used to endorse or promote products derived
 * from this software without specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */
#include "gprof.h"
#include "cg_arcs.h"
#include "core.h"
#include "hist.h"
#include "symtab.h"
#include "vax.h"

/*
 * A symbol to be the child of indirect calls:
 */
Sym indirectchild;


static operandenum
operandmode(modep)
    struct modebyte	*modep;
{
    long	usesreg = modep->regfield;
    
    switch (modep->modefield) {
	case 0:
	case 1:
	case 2:
	case 3:
	    return literal;
	case 4:
	    return indexed;
	case 5:
	    return reg;
	case 6:
	    return regdef;
	case 7:
	    return autodec;
	case 8:
	    return usesreg != PC ? autoinc : immediate;
	case 9:
	    return usesreg != PC ? autoincdef : absolute;
	case 10:
	    return usesreg != PC ? bytedisp : byterel;
	case 11:
	    return usesreg != PC ? bytedispdef : bytereldef;
	case 12:
	    return usesreg != PC ? worddisp : wordrel;
	case 13:
	    return usesreg != PC ? worddispdef : wordreldef;
	case 14:
	    return usesreg != PC ? longdisp : longrel;
	case 15:
	    return usesreg != PC ? longdispdef : longreldef;
    }
    /* NOTREACHED */
}

static char *
operandname(mode)
    operandenum	mode;
{
    
    switch (mode) {
	case literal:
	    return "literal";
	case indexed:
	    return "indexed";
	case reg:
	    return "register";
	case regdef:
	    return "register deferred";
	case autodec:
	    return "autodecrement";
	case autoinc:
	    return "autoincrement";
	case autoincdef:
	    return "autoincrement deferred";
	case bytedisp:
	    return "byte displacement";
	case bytedispdef:
	    return "byte displacement deferred";
	case byterel:
	    return "byte relative";
	case bytereldef:
	    return "byte relative deferred";
	case worddisp:
	    return "word displacement";
	case worddispdef:
	    return "word displacement deferred";
	case wordrel:
	    return "word relative";
	case wordreldef:
	    return "word relative deferred";
	case immediate:
	    return "immediate";
	case absolute:
	    return "absolute";
	case longdisp:
	    return "long displacement";
	case longdispdef:
	    return "long displacement deferred";
	case longrel:
	    return "long relative";
	case longreldef:
	    return "long relative deferred";
    }
    /* NOTREACHED */
}

static long
operandlength(modep)
    struct modebyte	*modep;
{
    
    switch (operandmode(modep)) {
	case literal:
	case reg:
	case regdef:
	case autodec:
	case autoinc:
	case autoincdef:
	    return 1;
	case bytedisp:
	case bytedispdef:
	case byterel:
	case bytereldef:
	    return 2;
	case worddisp:
	case worddispdef:
	case wordrel:
	case wordreldef:
	    return 3;
	case immediate:
	case absolute:
	case longdisp:
	case longdispdef:
	case longrel:
	case longreldef:
	    return 5;
	case indexed:
	    return 1+operandlength((struct modebyte *) ((char *) modep) + 1);
    }
    /* NOTREACHED */
}

static bfd_vma
reladdr(modep)
    struct modebyte	*modep;
{
    operandenum	mode = operandmode(modep);
    char	*cp;
    short	*sp;
    long	*lp;

    cp = (char *) modep;
    ++cp;			/* skip over the mode */
    switch (mode) {
	default:
	    fprintf(stderr, "[reladdr] not relative address\n");
	    return (bfd_vma) modep;
	case byterel:
	    return (bfd_vma) (cp + sizeof *cp + *cp);
	case wordrel:
	    sp = (short *) cp;
	    return (bfd_vma) (cp + sizeof *sp + *sp);
	case longrel:
	    lp = (long *) cp;
	    return (bfd_vma) (cp + sizeof *lp + *lp);
    }
}


void
find_call(parent, p_lowpc, p_highpc)
     Sym *parent;
     bfd_vma p_lowpc;
     bfd_vma p_highpc;
{
    unsigned char *instructp;
    long length;
    Sym *child;
    operandenum mode;
    operandenum firstmode;
    bfd_vma destpc;
    static bool inited = FALSE;

    if (!inited) {
	inited = TRUE;
	sym_init(&indirectchild);
	indirectchild.cg.prop.fract = 1.0;
	indirectchild.cg.cyc.head = &indirectchild;
    } /* if */

    if (core_text_space == 0) {
	return;
    }
    if (p_lowpc < s_lowpc) {
	p_lowpc = s_lowpc;
    }
    if (p_highpc > s_highpc) {
	p_highpc = s_highpc;
    }
    DBG(CALLDEBUG, printf("[findcall] %s: 0x%lx to 0x%lx\n",
			  parent->name, p_lowpc, p_highpc));
    for (  instructp = (unsigned char*) core_text_space + p_lowpc ;
	    instructp < (unsigned char*) core_text_space + p_highpc ;
	    instructp += length) {
	length = 1;
	if (*instructp == CALLS) {
		/*
		 *	maybe a calls, better check it out.
		 *	skip the count of the number of arguments.
		 */
	    DBG(CALLDEBUG,
		printf("[findcall]\t0x%x:calls",
		       instructp - (unsigned char*) core_text_space));
	    firstmode = operandmode((struct modebyte *) (instructp+length));
	    switch (firstmode) {
		case literal:
		case immediate:
		    break;
		default:
		    goto botched;
	    }
	    length += operandlength((struct modebyte *) (instructp+length));
	    mode = operandmode((struct modebyte *) (instructp + length));
	    DBG(CALLDEBUG,
		printf("\tfirst operand is %s", operandname(firstmode));
		printf("\tsecond operand is %s\n", operandname(mode)));
	    switch (mode) {
		case regdef:
		case bytedispdef:
		case worddispdef:
		case longdispdef:
		case bytereldef:
		case wordreldef:
		case longreldef:
			/*
			 *	indirect call: call through pointer
			 *	either	*d(r)	as a parameter or local
			 *		(r)	as a return value
			 *		*f	as a global pointer
			 *	[are there others that we miss?,
			 *	 e.g. arrays of pointers to functions???]
			 */
		    arc_add(parent, &indirectchild, (long) 0);
		    length += operandlength(
				(struct modebyte *) (instructp + length));
		    continue;
		case byterel:
		case wordrel:
		case longrel:
			/*
			 *	regular pc relative addressing
			 *	check that this is the address of 
			 *	a function.
			 */
		    destpc = reladdr((struct modebyte *) (instructp+length))
				- (bfd_vma) core_text_space;
		    if (destpc >= s_lowpc && destpc <= s_highpc) {
			child = sym_lookup(&symtab, destpc);
			DBG(CALLDEBUG,
			    printf("[findcall]\tdestpc 0x%lx", destpc);
			    printf(" child->name %s", child->name);
			    printf(" child->addr 0x%lx\n", child->addr);
			    );
			if (child->addr == destpc) {
				/*
				 *	a hit
				 */
			    arc_add(parent, child, (long) 0);
			    length += operandlength((struct modebyte *)
					    (instructp + length));
			    continue;
			}
			goto botched;
		    }
			/*
			 *	else:
			 *	it looked like a calls,
			 *	but it wasn't to anywhere.
			 */
		    goto botched;
		default:
		botched:
			/*
			 *	something funny going on.
			 */
		    DBG(CALLDEBUG, printf("[findcall]\tbut it's a botch\n"));
		    length = 1;
		    continue;
	    }
	}
    }
}