Commit 897c7801 authored by Matthias Braun's avatar Matthias Braun
Browse files

flags fixup phase

[r15763]
parent 19f88633
/*
* 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 modifies schedule so flags dependencies are respected.
* @author Matthias Braun, Christoph Mallon
* @version $Id: besched.h 14693 2007-06-21 15:35:49Z beck $
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "irgwalk.h"
#include "irnode_t.h"
#include "irtools.h"
#include "ircons.h"
#include "iredges_t.h"
#include "irprintf.h"
#include "error.h"
#include "beflags.h"
#include "bearch_t.h"
#include "beirg_t.h"
#include "besched_t.h"
static const arch_env_t *arch_env = NULL;
static const arch_register_class_t *flag_class = NULL;
static const arch_register_t *flags_reg = NULL;
static func_rematerialize remat = NULL;
static ir_node *default_remat(ir_node *node, ir_node *after)
{
ir_node *copy = exact_copy(node);
sched_add_after(after, copy);
return copy;
}
/**
* tests wether we can legally move node node after node after
* (only works for nodes in same block)
*/
static int can_move(ir_node *node, ir_node *after)
{
const ir_edge_t *edge;
assert(get_nodes_block(node) == get_nodes_block(after));
/* TODO respect dep edges */
assert(get_irn_n_edges_kind(node, EDGE_KIND_DEP) == 0);
/** all users have to be after the after node */
foreach_out_edge(node, edge) {
ir_node *out = get_edge_src_irn(edge);
if(is_Proj(out)) {
const ir_edge_t *edge2;
assert(get_irn_n_edges_kind(out, EDGE_KIND_DEP) == 0);
foreach_out_edge(out, edge2) {
ir_node *out2 = get_edge_src_irn(edge2);
/* phi represents a usage at block end */
if(is_Phi(out2))
continue;
if(sched_get_time_step(out2) <= sched_get_time_step(after)) {
return 0;
}
}
} else {
/* phi represents a usage at block end */
if(is_Phi(out))
continue;
if(sched_get_time_step(out) <= sched_get_time_step(after)) {
return 0;
}
}
}
ir_fprintf(stderr, "Can move node %+F after node %+F\n", node, after);
return 1;
}
static void rematerialize_or_move(ir_node *flags_needed, ir_node *node,
ir_node *flag_consumers, int pn)
{
ir_node *n;
ir_node *copy;
ir_node *value;
if(can_move(flags_needed, node)) {
/* move it */
sched_remove(flags_needed);
sched_add_after(node, flags_needed);
return;
}
copy = remat(flags_needed, node);
if(get_irn_mode(copy) == mode_T) {
ir_node *block = get_nodes_block(copy);
ir_mode *mode = flag_class->mode;
value = new_rd_Proj(NULL, current_ir_graph, block,
copy, mode, pn);
} else {
value = copy;
}
n = flag_consumers;
do {
int i;
int arity = get_irn_arity(n);
for(i = 0; i < arity; ++i) {
ir_node *in = get_irn_n(n, i);
in = skip_Proj(in);
if(in == flags_needed) {
set_irn_n(n, i, value);
break;
}
}
n = get_irn_link(n);
} while(n != NULL);
}
static void fix_flags_walker(ir_node *block, void *env)
{
ir_node *node;
ir_node *flags_needed = NULL;
ir_node *flag_consumers = NULL;
int pn;
(void) env;
sched_foreach_reverse(block, node) {
int i, arity;
ir_node *new_flags_needed = NULL;
if(node == flags_needed) {
/* all ok */
flags_needed = NULL;
flag_consumers = NULL;
}
/* test wether node destroys the flags */
if(flags_needed != NULL && arch_irn_is(arch_env, node, modify_flags)) {
/* rematerialize */
rematerialize_or_move(flags_needed, node, flag_consumers, pn);
flags_needed = NULL;
flag_consumers = NULL;
}
/* test wether the current node needs flags */
arity = get_irn_arity(node);
for(i = 0; i < arity; ++i) {
//ir_node *in = get_irn_n(node, i);
const arch_register_class_t *cls
= arch_get_irn_reg_class(arch_env, node, i);
if(cls == flag_class) {
assert(new_flags_needed == NULL);
new_flags_needed = get_irn_n(node, i);
}
}
if(new_flags_needed == NULL)
continue;
if(new_flags_needed != flags_needed) {
if(flags_needed != NULL) {
/* rematerialize node */
rematerialize_or_move(flags_needed, node, flag_consumers, pn);
flags_needed = NULL;
flag_consumers = NULL;
}
if(get_nodes_block(new_flags_needed) != block) {
panic("remat across blocks not implemented yet");
flags_needed = NULL;
flag_consumers = NULL;
} else {
flags_needed = new_flags_needed;
arch_set_irn_register(arch_env, flags_needed, flags_reg);
if(is_Proj(flags_needed)) {
pn = get_Proj_proj(flags_needed);
flags_needed = get_Proj_pred(flags_needed);
}
flag_consumers = node;
set_irn_link(flag_consumers, NULL);
assert(arch_irn_is(arch_env, flags_needed, rematerializable));
}
} else {
/* link all consumers in a list */
set_irn_link(flag_consumers, node);
flag_consumers = node;
}
}
assert(flags_needed == NULL);
assert(flag_consumers == NULL);
}
void be_sched_fix_flags(be_irg_t *birg, const arch_register_class_t *flag_cls,
func_rematerialize remat_func)
{
ir_graph *irg = be_get_birg_irg(birg);
arch_env = be_get_birg_arch_env(birg);
flag_class = flag_cls;
flags_reg = & flag_class->regs[0];
remat = remat_func;
if(remat == NULL)
remat = &default_remat;
set_using_irn_link(irg);
irg_block_walk_graph(irg, fix_flags_walker, NULL, NULL);
clear_using_irn_link(irg);
}
/*
* 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 modifies schedule so flags dependencies are respected.
* @author Matthias Braun, Christoph Mallon
* @version $Id: besched.h 14693 2007-06-21 15:35:49Z beck $
*/
#ifndef FIRM_BE_BEFLAGS_H
#define FIRM_BE_BEFLAGS_H
#include "bearch.h"
#include "beirg.h"
typedef ir_node * (*func_rematerialize) (ir_node *node, ir_node *after);
/**
* Walks the schedule and ensures that flags aren't destroyed between producer
* and consumer of flags. It does so by moving down/rematerialising of the
* nodes. This does not work across blocks.
*/
void be_sched_fix_flags(be_irg_t *birg, const arch_register_class_t *flag_cls,
func_rematerialize remat_func);
#endif
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