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/*
    Nios-sim - one simple NIOSII simulator only for personal interest and fun.
    Copyright (C) 2010  chysun2000@gmail.com

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License along
    with this program; if not, write to the Free Software Foundation, Inc.,
    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/

#include <stdio.h>
#include "public.h"
#include "niosii.h"
#include "instruction.h"

static uint32_t call(struct NIOS_CPU * cpu, uint32_t code)
{
	def_j_type_code;
	uint32_t imm26 = (uint32_t)instr->imm26;

	cpu->gp_regs[ra] = cpu->pc + 4;
	cpu->pc = (imm26 * 4) | (cpu->pc & 0xF0000000);
	return PC_INC_BY_INSTR;
}

static uint32_t jmpi(struct NIOS_CPU * cpu, uint32_t code)
{
	def_j_type_code;
	cpu->pc = (((uint32_t)(instr->imm26) * 4) & 0xFFFFFFF)| (cpu->pc & 0xF0000000);
	return PC_INC_BY_INSTR;
}

#define J_TYPE_HANDLER_COUNT (0x40)
struct j_type_handler j_type_handlers[J_TYPE_HANDLER_COUNT] = {
	[CALL] = handler_item(call),
	[JMPI] = handler_item(jmpi)
};