irnode.c

/*
 * Copyright (C) 1995-2008 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   Representation of an intermediate operation.
 * @author  Martin Trapp, Christian Schaefer, Goetz Lindenmaier, Michael Beck
 */
#include "config.h"

#include <string.h>

#include "pset_new.h"
#include "ident.h"
#include "irnode_t.h"
#include "irgraph_t.h"
#include "irmode_t.h"
#include "irbackedge_t.h"
#include "irdump.h"
#include "irop_t.h"
#include "irprog_t.h"
#include "iredgekinds.h"
#include "iredges_t.h"
#include "ircons.h"
#include "error.h"

#include "irhooks.h"
#include "irtools.h"
#include "util.h"

#include "beinfo.h"

/* some constants fixing the positions of nodes predecessors
   in the in array */
#define CALL_PARAM_OFFSET     (n_Call_max+1)
#define BUILTIN_PARAM_OFFSET  (n_Builtin_max+1)
#define ASM_PARAM_OFFSET      (n_ASM_max+1)
#define SEL_INDEX_OFFSET      (n_Sel_max+1)
#define RETURN_RESULT_OFFSET  (n_Return_max+1)
#define END_KEEPALIVE_OFFSET  0

static const char *relation_names [] = {
	"false",
	"equal",
	"less",
	"less_equal",
	"greater",
	"greater_equal",
	"less_greater",
	"less_equal_greater",
	"unordered",
	"unordered_equal",
	"unordered_less",
	"unordered_less_equal",
	"unordered_greater",
	"unordered_greater_equal",
	"not_equal",
	"true"
};

const char *get_relation_string(ir_relation relation)
{
	assert(relation < (ir_relation)ARRAY_SIZE(relation_names));
	return relation_names[relation];
}

ir_relation get_negated_relation(ir_relation relation)
{
	return relation ^ ir_relation_true;
}

ir_relation get_inversed_relation(ir_relation relation)
{
	ir_relation code    = relation & ~(ir_relation_less|ir_relation_greater);
	bool        less    = relation & ir_relation_less;
	bool        greater = relation & ir_relation_greater;
	code |= (less ? ir_relation_greater : ir_relation_false)
	      | (greater ? ir_relation_less : ir_relation_false);
	return code;
}

/**
 * Indicates, whether additional data can be registered to ir nodes.
 * If set to 1, this is not possible anymore.
 */
static int forbid_new_data = 0;

unsigned firm_add_node_size = 0;


unsigned firm_register_additional_node_data(unsigned size)
{
	assert(!forbid_new_data && "Too late to register additional node data");

	if (forbid_new_data)
		return 0;

	return firm_add_node_size += size;
}


void init_irnode(void)
{
	/* Forbid the addition of new data to an ir node. */
	forbid_new_data = 1;
}

struct struct_align {
	char c;
	struct s {
		int i;
		float f;
		double d;
	} s;
};

ir_node *new_ir_node(dbg_info *db, ir_graph *irg, ir_node *block, ir_op *op,
                     ir_mode *mode, int arity, ir_node *const *in)
{
	ir_node *res;
	unsigned align = offsetof(struct struct_align, s) - 1;
	unsigned add_node_size = (firm_add_node_size + align) & ~align;
	size_t node_size = offsetof(ir_node, attr) + op->attr_size + add_node_size;
	char *p;
	int i;

	assert(irg);
	assert(op);
	assert(mode);
	p = (char*)obstack_alloc(irg->obst, node_size);
	memset(p, 0, node_size);
	res = (ir_node *)(p + add_node_size);

	res->kind     = k_ir_node;
	res->op       = op;
	res->mode     = mode;
	res->visited  = 0;
	res->node_idx = irg_register_node_idx(irg, res);
	res->link     = NULL;
	res->deps     = NULL;

	if (arity < 0) {
		res->in = NEW_ARR_F(ir_node *, 1);  /* 1: space for block */
	} else {
		/* not nice but necessary: End and Sync must always have a flexible array */
		if (op == op_End || op == op_Sync)
			res->in = NEW_ARR_F(ir_node *, (arity+1));
		else
			res->in = NEW_ARR_D(ir_node *, irg->obst, (arity+1));
		memcpy(&res->in[1], in, sizeof(ir_node *) * arity);
	}

	res->in[0]   = block;
	set_irn_dbg_info(res, db);
	res->node_nr = get_irp_new_node_nr();

	for (i = 0; i < EDGE_KIND_LAST; ++i) {
		INIT_LIST_HEAD(&res->edge_info[i].outs_head);
		/* edges will be build immediately */
		res->edge_info[i].edges_built = 1;
		res->edge_info[i].out_count = 0;
	}

	/* don't put this into the for loop, arity is -1 for some nodes! */
	edges_notify_edge(res, -1, res->in[0], NULL, irg);
	for (i = 1; i <= arity; ++i)
		edges_notify_edge(res, i - 1, res->in[i], NULL, irg);

	hook_new_node(irg, res);
	if (get_irg_phase_state(irg) == phase_backend) {
		be_info_new_node(irg, res);
	}

	return res;
}

int (is_ir_node)(const void *thing)
{
	return is_ir_node_(thing);
}

int (get_irn_arity)(const ir_node *node)
{
	return get_irn_arity_(node);
}

ir_node **get_irn_in(const ir_node *node)
{
	return node->in;
}

void set_irn_in(ir_node *node, int arity, ir_node **in)
{
	int i;
	ir_node *** pOld_in;
	ir_graph *irg = get_irn_irg(node);

	pOld_in = &node->in;

#ifndef NDEBUG
	assert(node != NULL && node->kind == k_ir_node);
	assert(arity >= 0);
	for (i = 0; i < arity; ++i) {
		assert(in[i] != NULL && in[0]->kind == k_ir_node);
	}
#endif

	for (i = 0; i < arity; i++) {
		if (i < (int)ARR_LEN(*pOld_in)-1)
			edges_notify_edge(node, i, in[i], (*pOld_in)[i+1], irg);
		else
			edges_notify_edge(node, i, in[i], NULL,            irg);
	}
	for (;i < (int)ARR_LEN(*pOld_in)-1; i++) {
		edges_notify_edge(node, i, NULL, (*pOld_in)[i+1], irg);
	}

	if (arity != (int)ARR_LEN(*pOld_in) - 1) {
		ir_node * block = (*pOld_in)[0];
		*pOld_in = NEW_ARR_D(ir_node *, irg->obst, arity + 1);
		(*pOld_in)[0] = block;
	}
	fix_backedges(irg->obst, node);

	memcpy((*pOld_in) + 1, in, sizeof(ir_node *) * arity);

	/* update irg flags */
	clear_irg_properties(irg, IR_GRAPH_PROPERTY_CONSISTENT_OUTS | IR_GRAPH_PROPERTY_CONSISTENT_LOOPINFO);
}

ir_node *(get_irn_n)(const ir_node *node, int n)
{
	return get_irn_n_(node, n);
}

void set_irn_n(ir_node *node, int n, ir_node *in)
{
	ir_graph *irg = get_irn_irg(node);
	assert(node && node->kind == k_ir_node);
	assert(-1 <= n);
	assert(n < get_irn_arity(node));
	assert(in && in->kind == k_ir_node);

	/* Call the hook */
	hook_set_irn_n(node, n, in, node->in[n + 1]);

	/* Here, we rely on src and tgt being in the current ir graph */
	edges_notify_edge(node, n, in, node->in[n + 1], irg);

	node->in[n + 1] = in;

	/* update irg flags */
	clear_irg_properties(irg, IR_GRAPH_PROPERTY_CONSISTENT_OUTS | IR_GRAPH_PROPERTY_CONSISTENT_LOOPINFO);
}

int add_irn_n(ir_node *node, ir_node *in)
{
	int pos;
	ir_graph *irg = get_irn_irg(node);

	assert(node->op->opar == oparity_dynamic);
	pos = ARR_LEN(node->in) - 1;
	ARR_APP1(ir_node *, node->in, in);
	edges_notify_edge(node, pos, node->in[pos + 1], NULL, irg);

	/* Call the hook */
	hook_set_irn_n(node, pos, node->in[pos + 1], NULL);

	return pos;
}

void del_Sync_n(ir_node *n, int i)
{
	int      arity     = get_Sync_n_preds(n);
	ir_node *last_pred = get_Sync_pred(n, arity - 1);
	set_Sync_pred(n, i, last_pred);
	edges_notify_edge(n, arity - 1, NULL, last_pred, get_irn_irg(n));
	ARR_SHRINKLEN(get_irn_in(n), arity);
}

int (get_irn_deps)(const ir_node *node)
{
	return get_irn_deps_(node);
}

ir_node *(get_irn_dep)(const ir_node *node, int pos)
{
	return get_irn_dep_(node, pos);
}

void set_irn_dep(ir_node *node, int pos, ir_node *dep)
{
	ir_node *old;
	ir_graph *irg;

	assert(node->deps && "dependency array node yet allocated. use add_irn_dep()");
	assert(pos >= 0 && pos < (int)ARR_LEN(node->deps) && "dependency index out of range");
	assert(dep != NULL);
	old = node->deps[pos];
	node->deps[pos] = dep;
	irg = get_irn_irg(node);
	if (edges_activated_kind(irg, EDGE_KIND_DEP))
		edges_notify_edge_kind(node, pos, dep, old, EDGE_KIND_DEP, irg);
}

void add_irn_dep(ir_node *node, ir_node *dep)
{
	ir_graph *irg;
	assert(dep != NULL);
	if (node->deps == NULL) {
		node->deps = NEW_ARR_F(ir_node *, 0);
	}
	ARR_APP1(ir_node*, node->deps, dep);
	irg = get_irn_irg(node);
	if (edges_activated_kind(irg, EDGE_KIND_DEP))
		edges_notify_edge_kind(node, ARR_LEN(node->deps)-1, dep, NULL, EDGE_KIND_DEP, irg);
}

void delete_irn_dep(ir_node *node, ir_node *dep)
{
	size_t i;
	size_t n_deps;
	if (node->deps == NULL)
		return;

	n_deps = ARR_LEN(node->deps);
	for (i = 0; i < n_deps; ++i) {
		if (node->deps[i] == dep) {
			set_irn_dep(node, i, node->deps[n_deps-1]);
			edges_notify_edge(node, i, NULL, dep, get_irn_irg(node));
			ARR_SHRINKLEN(node->deps, n_deps-1);
			break;
		}
	}
}

void add_irn_deps(ir_node *tgt, ir_node *src)
{
	int i, n;

	for (i = 0, n = get_irn_deps(src); i < n; ++i)
		add_irn_dep(tgt, get_irn_dep(src, i));
}


ir_mode *(get_irn_mode)(const ir_node *node)
{
	return get_irn_mode_(node);
}

void (set_irn_mode)(ir_node *node, ir_mode *mode)
{
	set_irn_mode_(node, mode);
}

ir_op *(get_irn_op)(const ir_node *node)
{
	return get_irn_op_(node);
}

void (set_irn_op)(ir_node *node, ir_op *op)
{
	set_irn_op_(node, op);
}

unsigned (get_irn_opcode)(const ir_node *node)
{
	return get_irn_opcode_(node);
}

const char *get_irn_opname(const ir_node *node)
{
	return get_id_str(node->op->name);
}

ident *get_irn_opident(const ir_node *node)
{
	assert(node);
	return node->op->name;
}

ir_visited_t (get_irn_visited)(const ir_node *node)
{
	return get_irn_visited_(node);
}

void (set_irn_visited)(ir_node *node, ir_visited_t visited)
{
	set_irn_visited_(node, visited);
}

void (mark_irn_visited)(ir_node *node)
{
	mark_irn_visited_(node);
}

int (irn_visited)(const ir_node *node)
{
	return irn_visited_(node);
}

int (irn_visited_else_mark)(ir_node *node)
{
	return irn_visited_else_mark_(node);
}

void (set_irn_link)(ir_node *node, void *link)
{
	set_irn_link_(node, link);
}

void *(get_irn_link)(const ir_node *node)
{
	return get_irn_link_(node);
}

op_pin_state (get_irn_pinned)(const ir_node *node)
{
	return get_irn_pinned_(node);
}

op_pin_state (is_irn_pinned_in_irg) (const ir_node *node)
{
	return is_irn_pinned_in_irg_(node);
}

void set_irn_pinned(ir_node *node, op_pin_state state)
{
	/* due to optimization an opt may be turned into a Tuple */
	if (is_Tuple(node))
		return;

	assert(node && get_op_pinned(get_irn_op(node)) >= op_pin_state_exc_pinned);
	assert(state == op_pin_state_pinned || state == op_pin_state_floats);

	node->attr.except.pin_state = state;
}

long get_irn_node_nr(const ir_node *node)
{
	assert(node);
	return node->node_nr;
}

void *(get_irn_generic_attr)(ir_node *node)
{
	assert(is_ir_node(node));
	return get_irn_generic_attr_(node);
}

const void *(get_irn_generic_attr_const)(const ir_node *node)
{
	assert(is_ir_node(node));
	return get_irn_generic_attr_const_(node);
}

unsigned (get_irn_idx)(const ir_node *node)
{
	assert(is_ir_node(node));
	return get_irn_idx_(node);
}

int get_irn_pred_pos(ir_node *node, ir_node *arg)
{
	int i;
	for (i = get_irn_arity(node) - 1; i >= 0; i--) {
		if (get_irn_n(node, i) == arg)
			return i;
	}
	return -1;
}

ir_node *(get_nodes_block)(const ir_node *node)
{
	return get_nodes_block_(node);
}

void set_nodes_block(ir_node *node, ir_node *block)
{
	assert(!is_Block(node));
	set_irn_n(node, -1, block);
}

ir_type *is_frame_pointer(const ir_node *n)
{
	if (is_Proj(n) && (get_Proj_proj(n) == pn_Start_P_frame_base)) {
		ir_node *start = get_Proj_pred(n);
		if (is_Start(start)) {
			return get_irg_frame_type(get_irn_irg(start));
		}
	}
	return NULL;
}

ir_node **get_Block_cfgpred_arr(ir_node *node)
{
	assert(is_Block(node));
	return (ir_node **)&(get_irn_in(node)[1]);
}

int (get_Block_n_cfgpreds)(const ir_node *node)
{
	return get_Block_n_cfgpreds_(node);
}

ir_node *(get_Block_cfgpred)(const ir_node *node, int pos)
{
	return get_Block_cfgpred_(node, pos);
}

void set_Block_cfgpred(ir_node *node, int pos, ir_node *pred)
{
	assert(is_Block(node));
	set_irn_n(node, pos, pred);
}

int get_Block_cfgpred_pos(const ir_node *block, const ir_node *pred)
{
	int i;

	for (i = get_Block_n_cfgpreds(block) - 1; i >= 0; --i) {
		if (get_Block_cfgpred_block(block, i) == pred)
			return i;
	}
	return -1;
}

ir_node *(get_Block_cfgpred_block)(const ir_node *node, int pos)
{
	return get_Block_cfgpred_block_(node, pos);
}

int get_Block_matured(const ir_node *node)
{
	assert(is_Block(node));
	return (int)node->attr.block.is_matured;
}

void set_Block_matured(ir_node *node, int matured)
{
	assert(is_Block(node));
	node->attr.block.is_matured = matured;
}

ir_visited_t (get_Block_block_visited)(const ir_node *node)
{
	return get_Block_block_visited_(node);
}

void (set_Block_block_visited)(ir_node *node, ir_visited_t visit)
{
	set_Block_block_visited_(node, visit);
}

void (mark_Block_block_visited)(ir_node *node)
{
	mark_Block_block_visited_(node);
}

int (Block_block_visited)(const ir_node *node)
{
	return Block_block_visited_(node);
}

ir_graph *(get_Block_irg)(const ir_node *block)
{
	return get_Block_irg_(block);
}

ir_entity *create_Block_entity(ir_node *block)
{
	ir_entity *entity;
	assert(is_Block(block));

	entity = block->attr.block.entity;
	if (entity == NULL) {
		ir_label_t nr = get_irp_next_label_nr();
		entity = new_label_entity(nr);
		set_entity_visibility(entity, ir_visibility_local);
		set_entity_linkage(entity, IR_LINKAGE_CONSTANT);
		set_entity_compiler_generated(entity, 1);

		block->attr.block.entity = entity;
	}
	return entity;
}

ir_node *(get_Block_phis)(const ir_node *block)
{
	return get_Block_phis_(block);
}

void (set_Block_phis)(ir_node *block, ir_node *phi)
{
	set_Block_phis_(block, phi);
}

void (add_Block_phi)(ir_node *block, ir_node *phi)
{
	add_Block_phi_(block, phi);
}

unsigned (get_Block_mark)(const ir_node *block)
{
	return get_Block_mark_(block);
}

void (set_Block_mark)(ir_node *block, unsigned mark)
{
	set_Block_mark_(block, mark);
}

int get_End_n_keepalives(const ir_node *end)
{
	assert(is_End(end));
	return (get_irn_arity(end) - END_KEEPALIVE_OFFSET);
}

ir_node *get_End_keepalive(const ir_node *end, int pos)
{
	assert(is_End(end));
	return get_irn_n(end, pos + END_KEEPALIVE_OFFSET);
}

void add_End_keepalive(ir_node *end, ir_node *ka)
{
	assert(is_End(end));
	add_irn_n(end, ka);
}

void set_End_keepalive(ir_node *end, int pos, ir_node *ka)
{
	assert(is_End(end));
	set_irn_n(end, pos + END_KEEPALIVE_OFFSET, ka);
}

void set_End_keepalives(ir_node *end, int n, ir_node *in[])
{
	size_t e;
	int    i;
	ir_graph *irg = get_irn_irg(end);

	/* notify that edges are deleted */
	for (e = END_KEEPALIVE_OFFSET; e < ARR_LEN(end->in) - 1; ++e) {
		edges_notify_edge(end, e, NULL, end->in[e + 1], irg);
	}
	ARR_RESIZE(ir_node *, end->in, n + 1 + END_KEEPALIVE_OFFSET);

	for (i = 0; i < n; ++i) {
		end->in[1 + END_KEEPALIVE_OFFSET + i] = in[i];
		edges_notify_edge(end, END_KEEPALIVE_OFFSET + i, end->in[1 + END_KEEPALIVE_OFFSET + i], NULL, irg);
	}

	/* update irg flags */
	clear_irg_properties(irg, IR_GRAPH_PROPERTY_CONSISTENT_OUTS);
}

void remove_End_keepalive(ir_node *end, ir_node *irn)
{
	int      n = get_End_n_keepalives(end);
	ir_graph *irg;

	int idx = -1;
	for (int i = n;;) {
		if (i-- == 0)
			return;

		ir_node *old_ka = end->in[1 + END_KEEPALIVE_OFFSET + i];

		/* find irn */
		if (old_ka == irn) {
			idx = i;
			break;
		}
	}
	irg = get_irn_irg(end);

	/* remove the edge */
	edges_notify_edge(end, idx, NULL, irn, irg);

	if (idx != n - 1) {
		/* exchange with the last one */
		ir_node *old = end->in[1 + END_KEEPALIVE_OFFSET + n - 1];
		edges_notify_edge(end, n - 1, NULL, old, irg);
		end->in[1 + END_KEEPALIVE_OFFSET + idx] = old;
		edges_notify_edge(end, idx, old, NULL, irg);
	}
	/* now n - 1 keeps, 1 block input */
	ARR_RESIZE(ir_node *, end->in, (n - 1) + 1 + END_KEEPALIVE_OFFSET);

	/* update irg flags */
	clear_irg_properties(irg, IR_GRAPH_PROPERTY_CONSISTENT_OUTS);
}

void remove_End_Bads_and_doublets(ir_node *end)
{
	pset_new_t keeps;
	int        idx, n = get_End_n_keepalives(end);
	ir_graph   *irg;
	bool       changed = false;

	if (n <= 0)
		return;

	irg = get_irn_irg(end);
	pset_new_init(&keeps);

	for (idx = n - 1; idx >= 0; --idx) {
		ir_node *ka = get_End_keepalive(end, idx);

		if (is_Bad(ka) || is_NoMem(ka) || pset_new_contains(&keeps, ka)) {
			changed = true;
			/* remove the edge */
			edges_notify_edge(end, idx, NULL, ka, irg);

			if (idx != n - 1) {
				/* exchange with the last one */
				ir_node *old = end->in[1 + END_KEEPALIVE_OFFSET + n - 1];
				edges_notify_edge(end, n - 1, NULL, old, irg);
				end->in[1 + END_KEEPALIVE_OFFSET + idx] = old;
				edges_notify_edge(end, idx, old, NULL, irg);
			}
			--n;
		} else {
			pset_new_insert(&keeps, ka);
		}
	}
	/* n keeps, 1 block input */
	ARR_RESIZE(ir_node *, end->in, n + 1 + END_KEEPALIVE_OFFSET);

	pset_new_destroy(&keeps);

	if (changed) {
		clear_irg_properties(irg, IR_GRAPH_PROPERTY_CONSISTENT_OUTS);
	}
}

void free_End(ir_node *end)
{
	assert(is_End(end));
	end->kind = k_BAD;
	DEL_ARR_F(end->in);
	end->in = NULL;   /* @@@ make sure we get an error if we use the
	                     in array afterwards ... */
}

size_t get_Return_n_ress(const ir_node *node)
{
	assert(is_Return(node));
	return (size_t)(get_irn_arity(node) - RETURN_RESULT_OFFSET);
}

ir_node **get_Return_res_arr(ir_node *node)
{
	assert(is_Return(node));
	if (get_Return_n_ress(node) > 0)
		return (ir_node **)&(get_irn_in(node)[1 + RETURN_RESULT_OFFSET]);
	else
		return NULL;
}

ir_node *get_Return_res(const ir_node *node, int pos)
{
	assert(is_Return(node));
	assert(pos >= 0);
	assert(get_Return_n_ress(node) > (size_t)pos);
	return get_irn_n(node, pos + RETURN_RESULT_OFFSET);
}

void set_Return_res(ir_node *node, int pos, ir_node *res)
{
	assert(is_Return(node));
	set_irn_n(node, pos + RETURN_RESULT_OFFSET, res);
}

int (is_Const_null)(const ir_node *node)
{
	return is_Const_null_(node);
}

int (is_Const_one)(const ir_node *node)
{
	return is_Const_one_(node);
}

int (is_Const_all_one)(const ir_node *node)
{
	return is_Const_all_one_(node);
}



symconst_kind get_SymConst_kind(const ir_node *node)
{
	assert(is_SymConst(node));
	return node->attr.symc.kind;
}

void set_SymConst_kind(ir_node *node, symconst_kind kind)
{
	assert(is_SymConst(node));
	node->attr.symc.kind = kind;
}

ir_type *get_SymConst_type(const ir_node *node)
{
	/* the cast here is annoying, but we have to compensate for
	   the skip_tip() */
	ir_node *irn = (ir_node *)node;
	assert(is_SymConst(node) &&
	       (SYMCONST_HAS_TYPE(get_SymConst_kind(node))));
	return irn->attr.symc.sym.type_p;
}

void set_SymConst_type(ir_node *node, ir_type *tp)
{
	assert(is_SymConst(node) &&
	       (SYMCONST_HAS_TYPE(get_SymConst_kind(node))));
	node->attr.symc.sym.type_p = tp;
}

ir_entity *get_SymConst_entity(const ir_node *node)
{
	assert(is_SymConst(node) && SYMCONST_HAS_ENT(get_SymConst_kind(node)));
	return node->attr.symc.sym.entity_p;
}

void set_SymConst_entity(ir_node *node, ir_entity *ent)
{
	assert(is_SymConst(node) && SYMCONST_HAS_ENT(get_SymConst_kind(node)));
	node->attr.symc.sym.entity_p  = ent;
}

ir_enum_const *get_SymConst_enum(const ir_node *node)
{
	assert(is_SymConst(node) && SYMCONST_HAS_ENUM(get_SymConst_kind(node)));
	return node->attr.symc.sym.enum_p;
}

void set_SymConst_enum(ir_node *node, ir_enum_const *ec)
{
	assert(is_SymConst(node) && SYMCONST_HAS_ENUM(get_SymConst_kind(node)));
	node->attr.symc.sym.enum_p  = ec;
}

union symconst_symbol
get_SymConst_symbol(const ir_node *node)
{
	assert(is_SymConst(node));