/*
 * Copyright (C) 1995-2007 University of Karlsruhe.  All right reserved.
 *
 * This file is part of libFirm.
 *
 * This file may be distributed and/or modified under the terms of the
 * GNU General Public License version 2 as published by the Free Software
 * Foundation and appearing in the file LICENSE.GPL included in the
 * packaging of this file.
 *
 * Licensees holding valid libFirm Professional Edition licenses may use
 * this file in accordance with the libFirm Commercial License.
 * Agreement provided with the Software.
 *
 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE.
 */

/**
 * @file
 * @brief       Processor architecture specification.
 * @author      Sebastian Hack
 * @version     $Id$
 */
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <string.h>

#include "bearch_t.h"
#include "ircons_t.h"
#include "irnode_t.h"
#include "xmalloc.h"

#include "bitset.h"
#include "pset.h"
#include "raw_bitset.h"

#include "irprintf.h"

/* Initialize the architecture environment struct. */
arch_env_t *arch_env_init(arch_env_t *env, const arch_isa_if_t *isa_if, FILE *file_handle, be_main_env_t *main_env)
{
	memset(env, 0, sizeof(*env));
	env->isa                  = isa_if->init(file_handle);
	env->isa->main_env        = main_env;
	return env;
}

arch_env_t *arch_env_push_irn_handler(arch_env_t *env,
                                      const arch_irn_handler_t *handler)
{
	assert(env->handlers_tos < ARCH_MAX_HANDLERS);
	env->handlers[env->handlers_tos++] = handler;
	return env;
}

const arch_irn_handler_t *arch_env_pop_irn_handler(arch_env_t *env)
{
   	assert(env->handlers_tos > 0 && env->handlers_tos <= ARCH_MAX_HANDLERS);
	return env->handlers[--env->handlers_tos];
}

static const arch_irn_ops_t *fallback_irn_ops = NULL;

int arch_register_class_put(const arch_register_class_t *cls, bitset_t *bs)
{
	if(bs) {
		int i, n;
		for(i = 0, n = cls->n_regs; i < n; ++i)
			bitset_set(bs, i);
	}

	return cls->n_regs;
}

/**
 * Get the isa responsible for a node.
 * @param env The arch environment with the isa stack.
 * @param irn The node to get the responsible isa for.
 * @return The irn operations given by the responsible isa.
 */
static INLINE const arch_irn_ops_t *
get_irn_ops(const arch_env_t *env, const ir_node *irn)
{
	int i;

	for(i = env->handlers_tos - 1; i >= 0; --i) {
		const arch_irn_handler_t *handler = env->handlers[i];
		const arch_irn_ops_t *ops = handler->get_irn_ops(handler, irn);

		if(ops)
			return ops;
	}

	return fallback_irn_ops;
}

const arch_irn_ops_t *arch_get_irn_ops(const arch_env_t *env, const ir_node *irn) {
	return get_irn_ops(env, irn);
}

const arch_register_req_t *arch_get_register_req(const arch_env_t *env,
                                                 const ir_node *irn, int pos)
{
	const arch_irn_ops_t *ops = get_irn_ops(env, irn);
	return ops->impl->get_irn_reg_req(ops, irn, pos);
}

void arch_set_frame_offset(const arch_env_t *env, ir_node *irn, int offset)
{
	const arch_irn_ops_t *ops = get_irn_ops(env, irn);
	ops->impl->set_frame_offset(ops, irn, offset);
}

ir_entity *arch_get_frame_entity(const arch_env_t *env, const ir_node *irn)
{
	const arch_irn_ops_t *ops = get_irn_ops(env, irn);
	return ops->impl->get_frame_entity(ops, irn);
}

void arch_set_frame_entity(const arch_env_t *env, ir_node *irn, ir_entity *ent)
{
	const arch_irn_ops_t *ops = get_irn_ops(env, irn);
	ops->impl->set_frame_entity(ops, irn, ent);
}

int arch_get_sp_bias(const arch_env_t *env, ir_node *irn)
{
	const arch_irn_ops_t *ops = get_irn_ops(env, irn);
	return ops->impl->get_sp_bias(ops, irn);
}

arch_inverse_t *arch_get_inverse(const arch_env_t *env, const ir_node *irn, int i, arch_inverse_t *inverse, struct obstack *obstack)
{
	const arch_irn_ops_t *ops = get_irn_ops(env, irn);

	if(ops->impl->get_inverse) {
		return ops->impl->get_inverse(ops, irn, i, inverse, obstack);
	} else {
		return NULL;
	}
}

int arch_possible_memory_operand(const arch_env_t *env, const ir_node *irn, unsigned int i) {
	const arch_irn_ops_t *ops = get_irn_ops(env, irn);

	if(ops->impl->possible_memory_operand) {
		return ops->impl->possible_memory_operand(ops, irn, i);
	} else {
		return 0;
	}
}

void arch_perform_memory_operand(const arch_env_t *env, ir_node *irn, ir_node *spill, unsigned int i) {
	const arch_irn_ops_t *ops = get_irn_ops(env, irn);

	if(ops->impl->perform_memory_operand) {
		ops->impl->perform_memory_operand(ops, irn, spill, i);
	} else {
		return;
	}
}

int arch_get_op_estimated_cost(const arch_env_t *env, const ir_node *irn)
{
	const arch_irn_ops_t *ops = get_irn_ops(env, irn);

	if(ops->impl->get_op_estimated_cost) {
		return ops->impl->get_op_estimated_cost(ops, irn);
	} else {
		return 1;
	}
}

int arch_is_possible_memory_operand(const arch_env_t *env, const ir_node *irn, int i)
{
   	const arch_irn_ops_t *ops = get_irn_ops(env, irn);

	if(ops->impl->possible_memory_operand) {
	   	return ops->impl->possible_memory_operand(ops, irn, i);
	} else {
		return 0;
	}
}

int arch_get_allocatable_regs(const arch_env_t *env, const ir_node *irn, int pos, bitset_t *bs)
{
	const arch_irn_ops_t *ops = get_irn_ops(env, irn);
	const arch_register_req_t *req = ops->impl->get_irn_reg_req(ops, irn, pos);

	if(req->type == arch_register_req_type_none) {
		bitset_clear_all(bs);
		return 0;
	}

	if(arch_register_req_is(req, limited)) {
		rbitset_copy_to_bitset(req->limited, bs);
		return bitset_popcnt(bs);
	}

	arch_register_class_put(req->cls, bs);
	return req->cls->n_regs;
}

void arch_put_non_ignore_regs(const arch_env_t *env,
                              const arch_register_class_t *cls, bitset_t *bs)
{
	int i;
	(void) env;

	for(i = 0; i < cls->n_regs; ++i) {
		if(!arch_register_type_is(&cls->regs[i], ignore))
			bitset_set(bs, i);
	}
}

int arch_count_non_ignore_regs(const arch_env_t *env,
                               const arch_register_class_t *cls)
{
	int i;
	int result = 0;
	(void) env;

	for(i = 0; i < cls->n_regs; ++i) {
		if(!arch_register_type_is(&cls->regs[i], ignore))
			result++;
	}

	return result;
}

int arch_is_register_operand(const arch_env_t *env,
    const ir_node *irn, int pos)
{
	const arch_irn_ops_t *ops = get_irn_ops(env, irn);
	const arch_register_req_t *req = ops->impl->get_irn_reg_req(ops, irn, pos);

	return req != NULL;
}

int arch_reg_is_allocatable(const arch_env_t *env, const ir_node *irn,
    int pos, const arch_register_t *reg)
{
	const arch_register_req_t *req;

	req = arch_get_register_req(env, irn, pos);

	if(req->type == arch_register_req_type_none)
		return 0;

	if(arch_register_req_is(req, limited)) {
		assert(arch_register_get_class(reg) == req->cls);
		return rbitset_is_set(req->limited, arch_register_get_index(reg));
	}

	return req->cls == reg->reg_class;
}

const arch_register_class_t *
arch_get_irn_reg_class(const arch_env_t *env, const ir_node *irn, int pos)
{
	const arch_irn_ops_t *ops = get_irn_ops(env, irn);
	const arch_register_req_t *req = ops->impl->get_irn_reg_req(ops, irn, pos);

	assert(req->type != arch_register_req_type_none || req->cls == NULL);

	return req->cls;
}

extern const arch_register_t *
arch_get_irn_register(const arch_env_t *env, const ir_node *irn)
{
	const arch_irn_ops_t *ops = get_irn_ops(env, irn);
	return ops->impl->get_irn_reg(ops, irn);
}

extern void arch_set_irn_register(const arch_env_t *env,
    ir_node *irn, const arch_register_t *reg)
{
	const arch_irn_ops_t *ops = get_irn_ops(env, irn);
	ops->impl->set_irn_reg(ops, irn, reg);
}

extern arch_irn_class_t arch_irn_classify(const arch_env_t *env, const ir_node *irn)
{
	const arch_irn_ops_t *ops = get_irn_ops(env, irn);
	return ops->impl->classify(ops, irn);
}

extern arch_irn_flags_t arch_irn_get_flags(const arch_env_t *env, const ir_node *irn)
{
	const arch_irn_ops_t *ops = get_irn_ops(env, irn);
	return ops->impl->get_flags(ops, irn);
}

extern const char *arch_irn_flag_str(arch_irn_flags_t fl)
{
	switch(fl) {
#define XXX(x) case arch_irn_flags_ ## x: return #x;
		XXX(dont_spill);
		XXX(ignore);
		XXX(rematerializable);
		XXX(modify_sp);
		XXX(modify_flags);
		XXX(none);
#undef XXX
	}
	return "n/a";
}

extern char *arch_register_req_format(char *buf, size_t len,
                                      const arch_register_req_t *req,
                                      const ir_node *node)
{
	char tmp[128];
	snprintf(buf, len, "class: %s", req->cls->name);

	if(arch_register_req_is(req, limited)) {
		unsigned n_regs = req->cls->n_regs;
		unsigned i;

		strncat(buf, " limited:", len);
		for(i = 0; i < n_regs; ++i) {
			if(rbitset_is_set(req->limited, i)) {
				const arch_register_t *reg = &req->cls->regs[i];
				strncat(buf, " ", len);
				strncat(buf, reg->name, len);
			}
		}
	}

	if(arch_register_req_is(req, should_be_same)) {
		const ir_node *same = get_irn_n(skip_Proj_const(node), req->other_same);
		ir_snprintf(tmp, sizeof(tmp), " same to: %+F", same);
		strncat(buf, tmp, len);
	}

	if(arch_register_req_is(req, should_be_different)) {
		const ir_node *different = get_irn_n(skip_Proj_const(node), req->other_different);
		ir_snprintf(tmp, sizeof(tmp), " different to: %+F", different);
		strncat(buf, tmp, len);
	}

	return buf;
}

static const arch_register_req_t no_requirement = {
	arch_register_req_type_none,
	NULL,
	NULL,
	-1,
	-1
};
const arch_register_req_t *arch_no_register_req = &no_requirement;