/* -*- linux-c -*- 
 * register access functions
 * Copyright (C) 2005 Intel Corporation.
 *
 * This file is part of systemtap, and is free software.  You can
 * redistribute it and/or modify it under the terms of the GNU General
 * Public License (GPL); either version 2, or (at your option) any
 * later version.
 */

#ifndef _REG_C_
#define _REG_C_

#if defined __ia64__

struct ia64_stap_get_arbsp_param {
	unsigned long ip;
	unsigned long *address;
};

static void ia64_stap_get_arbsp(struct unw_frame_info *info, void *arg)
{
	unsigned long ip;
	struct ia64_stap_get_arbsp_param *lp = arg;

	do {
		unw_get_ip(info, &ip);
		if (ip == 0)
			break;
		if (ip == lp->ip) {
			unw_get_bsp(info, (unsigned long*)&lp->address);
			return;
		}
	} while (unw_unwind(info) >= 0);
	lp->address = 0;
}

static long ia64_fetch_register(int regno, struct pt_regs *pt_regs)
{
	struct ia64_stap_get_arbsp_param pa;

	if (regno < 32 || regno > 127)
		return 0;

	pa.ip = pt_regs->cr_iip;
	unw_init_running(ia64_stap_get_arbsp, &pa);
	if (pa.address == 0)
		return 0;

	return *ia64_rse_skip_regs(pa.address, regno-32);
}

static void ia64_store_register(int regno,
		struct pt_regs *pt_regs,
		unsigned long value)
{
	struct ia64_stap_get_arbsp_param pa;
	unsigned long rsc_save = 0;

	if (regno < 32 || regno > 127)
		return;

	pa.ip = pt_regs->cr_iip;
	unw_init_running(ia64_stap_get_arbsp, &pa);
	if (pa.address == 0)
		return;
	*ia64_rse_skip_regs(pa.address, regno-32) = value;
	//Invalidate all stacked registers outside the current frame
	asm volatile( "mov %0=ar.rsc;;\n\t"
			"mov ar.rsc=0;;\n\t"
			"{\n\tloadrs;;\n\t\n\t\n\t}\n\t"
			"mov ar.rsc=%1\n\t"
			:"=r" (rsc_save):"r" (rsc_save):"memory");

	return;
}

#endif /* if defined __ia64__ */


#endif /* _REG_C_ */