quakeforge/tools/qfcc/source/dags.c
Bill Currie 6d5ffa9f8e [build] Move to non-recursive make
There's still some cleanup to do, but everything seems to be working
nicely: `make -j` works, `make distcheck` passes. There is probably
plenty of bitrot in the package directories (RPM, debian), though.

The vc project files have been removed since those versions are way out
of date and quakeforge is pretty much dependent on gcc now anyway.

Most of the old Makefile.am files  are now Makemodule.am.  This should
allow for new Makefile.am files that allow local building (to be added
on an as-needed bases).  The current remaining Makefile.am files are for
standalone sub-projects.a

The installable bins are currently built in the top-level build
directory. This may change if the clutter gets to be too much.

While this does make a noticeable difference in build times, the main
reason for the switch was to take care of the growing dependency issues:
now it's possible to build tools for code generation (eg, using qfcc and
ruamoko programs for code-gen).
2020-06-25 11:35:37 +09:00

1189 lines
30 KiB
C

/*
dags.c
DAG representation of basic blocks
Copyright (C) 2012 Bill Currie <bill@taniwha.org>
Author: Bill Currie <bill@taniwha.org>
Date: 2012/05/08
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:
Free Software Foundation, Inc.
59 Temple Place - Suite 330
Boston, MA 02111-1307, USA
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#ifdef HAVE_STRING_H
# include <string.h>
#endif
#ifdef HAVE_STRINGS_H
# include <strings.h>
#endif
#include <stdlib.h>
#include <ctype.h>
#include "qfalloca.h"
#include "QF/alloc.h"
#include "QF/dstring.h"
#include "QF/mathlib.h"
#include "QF/set.h"
#include "tools/qfcc/include/dags.h"
#include "tools/qfcc/include/diagnostic.h"
#include "tools/qfcc/include/dot.h"
#include "tools/qfcc/include/flow.h"
#include "tools/qfcc/include/function.h"
#include "tools/qfcc/include/options.h"
#include "tools/qfcc/include/qfcc.h"
#include "tools/qfcc/include/statements.h"
#include "tools/qfcc/include/strpool.h"
#include "tools/qfcc/include/symtab.h"
#include "tools/qfcc/include/type.h"
#include "tools/qfcc/include/value.h"
static daglabel_t *labels_freelist;
static dagnode_t *nodes_freelist;
static dag_t *dags_freelist;
static daglabel_t *daglabel_chain;
static void
flush_daglabels (void)
{
while (daglabel_chain) {
operand_t *op;
if ((op = daglabel_chain->op)) {
if (op->op_type == op_def)
op->o.def->daglabel = 0;
else if (op->op_type == op_temp)
op->o.tempop.daglabel = 0;
else if (op->op_type == op_value)
op->o.value->daglabel = 0;
else if (op->op_type == op_label)
op->o.label->daglabel = 0;
else
internal_error (op->expr, "unexpected operand type");
}
daglabel_chain = daglabel_chain->daglabel_chain;
}
}
static dag_t *
new_dag (void)
{
dag_t *dag;
ALLOC (256, dag_t, dags, dag);
return dag;
}
static daglabel_t *
new_label (dag_t *dag)
{
daglabel_t *label;
ALLOC (256, daglabel_t, labels, label);
label->daglabel_chain = daglabel_chain;
daglabel_chain = label;
label->number = dag->num_labels;
dag->labels[dag->num_labels++] = label;
return label;
}
static dagnode_t *
new_node (dag_t *dag)
{
dagnode_t *node;
ALLOC (256, dagnode_t, nodes, node);
node->parents = set_new ();
node->edges = set_new ();
node->identifiers = set_new ();
node->number = dag->num_nodes;
set_add (dag->roots, node->number); // nodes start out as root nodes
dag->nodes[dag->num_nodes++] = node;
return node;
}
const char *
daglabel_string (daglabel_t *label)
{
static dstring_t *str;
if ((label->opcode && label->op) || (!label->opcode && !label->op))
return "bad label";
if (label->opcode)
return label->opcode;
if (!str)
str = dstring_new ();
// operand_string might use quote_string, which returns a pointer to
// a static variable.
dstring_copystr (str, operand_string (label->op));
#if 0
if (label->op->type) {
dstring_appendstr (str, label->op->type->encoding);
}
#endif
return quote_string (str->str);
}
static daglabel_t *
opcode_label (dag_t *dag, const char *opcode, expr_t *expr)
{
daglabel_t *label;
label = new_label (dag);
label->opcode = opcode;
label->expr = expr;
return label;
}
static daglabel_t *
operand_label (dag_t *dag, operand_t *op)
{
def_t *def = 0;
ex_value_t *val = 0;
daglabel_t *label;
if (!op)
return 0;
if (op->op_type == op_temp) {
//while (op->o.tempop.alias)
// op = op->o.tempop.alias;
if (op->o.tempop.daglabel)
return op->o.tempop.daglabel;
label = new_label (dag);
label->op = op;
op->o.tempop.daglabel = label;
} else if (op->op_type == op_def) {
def = op->o.def;
if (def->daglabel)
return def->daglabel;
label = new_label (dag);
label->op = op;
def->daglabel = label;
} else if (op->op_type == op_value) {
val = op->o.value;
if (val->daglabel)
return val->daglabel;
label = new_label (dag);
label->op = op;
val->daglabel = label;
} else if (op->op_type == op_label) {
if (op->o.label->daglabel)
return op->o.label->daglabel;
label = new_label (dag);
label->op = op;
op->o.label->daglabel = label;
} else {
internal_error (op->expr, "unexpected operand type: %d", op->op_type);
}
return label;
}
static dagnode_t *
leaf_node (dag_t *dag, operand_t *op, expr_t *expr)
{
daglabel_t *label;
dagnode_t *node;
if (!op)
return 0;
node = new_node (dag);
node->tl = op->type;
label = operand_label (dag, op);
label->dagnode = node;
label->expr = expr;
node->label = label;
return node;
}
static __attribute__((pure)) dagnode_t *
dag_node (operand_t *op)
{
def_t *def;
dagnode_t *node = 0;
if (!op)
return 0;
if (op->op_type == op_def) {
def = op->o.def;
if (def->daglabel)
node = def->daglabel->dagnode;
} else if (op->op_type == op_temp) {
while (op->o.tempop.alias)
op = op->o.tempop.alias;
if (op->o.tempop.daglabel)
node = op->o.tempop.daglabel->dagnode;
} else if (op->op_type == op_value) {
if (op->o.value->daglabel)
node = op->o.value->daglabel->dagnode;
} else if (op->op_type == op_label) {
if (op->o.label->daglabel)
node = op->o.label->daglabel->dagnode;
}
return node;
}
static void
dag_make_leafs (dag_t *dag, statement_t *s, operand_t *operands[FLOW_OPERANDS])
{
int i;
flow_analyze_statement (s, 0, 0, 0, operands);
for (i = 1; i < FLOW_OPERANDS; i++) {
if (!dag_node (operands[i])) {
leaf_node (dag, operands[i], s->expr);
}
}
}
static void
dag_make_children (dag_t *dag, statement_t *s,
operand_t *operands[FLOW_OPERANDS],
dagnode_t *children[3])
{
int i;
flow_analyze_statement (s, 0, 0, 0, operands);
for (i = 0; i < 3; i++) {
dagnode_t *node = dag_node (operands[i + 1]);
dagnode_t *killer = 0;
if (node && node->killed) {
killer = node->killed;
node = 0;
}
if (!node) {
node = leaf_node (dag, operands[i + 1], s->expr);
}
if (killer) {
set_add (node->edges, killer->number);
}
children[i] = node;
}
}
static int
dagnode_deref_match (const dagnode_t *n, const daglabel_t *op,
dagnode_t *children[3])
{
int i;
for (i = 0; i < 2; i++) {
if (n->children[i] != children[i + 1])
return 0;
}
return 1;
}
static int
dagnode_match (const dagnode_t *n, const daglabel_t *op,
dagnode_t *children[3])
{
int i;
if (n->killed)
return 0;
if (!strcmp (op->opcode, ".")
&& n->label->opcode && !strcmp (n->label->opcode, ".="))
return dagnode_deref_match (n, op, children);
if (n->label->opcode != op->opcode)
return 0;
for (i = 0; i < 3; i++) {
if (n->children[i] != children[i])
return 0;
}
return 1;
}
static dagnode_t *
dagnode_search (dag_t *dag, daglabel_t *op, dagnode_t *children[3])
{
int i;
for (i = 0; i < dag->num_nodes; i++)
if (dagnode_match (dag->nodes[i], op, children))
return dag->nodes[i];
return 0;
}
static void
dagnode_add_children (dag_t *dag, dagnode_t *n, operand_t *operands[4],
dagnode_t *children[3])
{
int i;
for (i = 0; i < 3; i++) {
dagnode_t *child = children[i];
if ((n->children[i] = child)) {
n->types[i] = operands[i + 1]->type;
set_remove (dag->roots, child->number);
set_add (child->parents, n->number);
}
}
}
static int
dagnode_tempop_set_edges_visit (tempop_t *tempop, void *_node)
{
dagnode_t *node = (dagnode_t *) _node;
daglabel_t *label;
label = tempop->daglabel;
if (label && label->dagnode) {
set_add (node->edges, label->dagnode->number);
label->live = 1;
}
return 0;
}
static int
dagnode_def_set_edges_visit (def_t *def, void *_node)
{
dagnode_t *node = (dagnode_t *) _node;
daglabel_t *label;
label = def->daglabel;
if (label && label->dagnode) {
set_add (node->edges, label->dagnode->number);
label->live = 1;
}
return 0;
}
static int
dag_find_node (def_t *def, void *_daglabel)
{
daglabel_t **daglabel = (daglabel_t **) _daglabel;
if (def->daglabel && def->daglabel->dagnode) {
*daglabel = def->daglabel;
return def->daglabel->dagnode->number + 1; // ensure never 0
}
return 0;
}
static void
dagnode_set_edges (dag_t *dag, dagnode_t *n)
{
int i;
for (i = 0; i < 3; i++) {
dagnode_t *child = n->children[i];
if (child && n != child)
set_add (n->edges, child->number);
}
if (n->type == st_flow)
return;
for (i = 0; i < 3; i++) {
dagnode_t *child = n->children[i];
if (child) {
if (child->label->op) {
dagnode_t *node = child->label->dagnode;
operand_t *op = child->label->op;
if (node != child && node != n) {
set_add (node->edges, n->number);
}
if (op->op_type == op_value
&& op->o.value->lltype == ev_pointer
&& op->o.value->v.pointer.def) {
def_visit_all (op->o.value->v.pointer.def, 1,
dagnode_def_set_edges_visit, n);
}
if (op->op_type == op_def
&& (op->o.def->alias || op->o.def->alias_defs)) {
def_visit_all (op->o.def, 1,
dagnode_def_set_edges_visit, n);
}
if (op->op_type == op_temp
&& (op->o.tempop.alias || op->o.tempop.alias_ops)) {
tempop_visit_all (&op->o.tempop, 1,
dagnode_tempop_set_edges_visit, n);
}
}
if (n != child)
set_add (n->edges, child->number);
}
}
if (n->type == st_func) {
const char *num_params = 0;
int first_param = 0;
flowvar_t **flowvars = dag->flownode->graph->func->vars;
if (!strncmp (n->label->opcode, "<RCALL", 6)) {
num_params = n->label->opcode + 6;
first_param = 2;
} else if (!strncmp (n->label->opcode, "<CALL", 5)) {
num_params = n->label->opcode + 5;
} else if (!strcmp (n->label->opcode, "<RETURN>")) {
daglabel_t *label = n->children[0]->label;
if (!label->op) {
set_iter_t *lab_i;
for (lab_i = set_first (n->children[0]->identifiers); lab_i;
lab_i = set_next (lab_i)) {
label = dag->labels[lab_i->element];
}
}
label->live = 1;
}
if (num_params && isdigit (*num_params)) {
for (i = first_param; i < *num_params - '0'; i++) {
flowvar_t *var = flowvars[i + 1];
def_t *param_def = var->op->o.def;
daglabel_t *daglabel;
int param_node;
// FIXME hopefully only the one alias :P
param_node = def_visit_all (param_def, 0, dag_find_node,
&daglabel);
if (!param_node) {
bug (n->label->expr, ".param_%d not set for %s", i,
n->label->opcode);
continue;
}
daglabel->live = 1;
set_add (n->edges, param_node - 1);
}
}
}
}
static int
op_is_identifier (operand_t *op)
{
if (op->op_type == op_label)
return 0;
if (op->op_type == op_value)
return 0;
if (op->op_type == op_temp)
return 1;
if (op->op_type != op_def)
return 0;
return 1;
}
static int
dag_tempop_kill_aliases_visit (tempop_t *tempop, void *_l)
{
daglabel_t *l = (daglabel_t *) _l;
dagnode_t *node = l->dagnode;
daglabel_t *label;
if (tempop == &l->op->o.tempop)
return 0;
label = tempop->daglabel;
if (label && label->dagnode) {
set_add (node->edges, label->dagnode->number);
set_remove (node->edges, node->number);
label->dagnode->killed = node;
}
return 0;
}
static int
dag_def_kill_aliases_visit (def_t *def, void *_l)
{
daglabel_t *l = (daglabel_t *) _l;
dagnode_t *node = l->dagnode;;
daglabel_t *label;
if (def == l->op->o.def)
return 0;
label = def->daglabel;
if (label && label->dagnode) {
set_add (node->edges, label->dagnode->number);
set_remove (node->edges, node->number);
label->dagnode->killed = node;
}
return 0;
}
static void
dag_kill_aliases (daglabel_t *l)
{
operand_t *op = l->op;
if (op->op_type == op_temp) {
if (op->o.tempop.alias || op->o.tempop.alias_ops) {
tempop_visit_all (&op->o.tempop, 1,
dag_tempop_kill_aliases_visit, l);
}
} else if (op->op_type == op_def) {
if (op->o.def->alias || op->o.def->alias_defs) {
def_visit_all (op->o.def, 1, dag_def_kill_aliases_visit, l);
}
} else {
internal_error (op->expr, "rvalue assignment?");
}
}
static int
dag_tempop_live_aliases (tempop_t *tempop, void *_t)
{
if (tempop != _t && tempop->daglabel)
tempop->daglabel->live = 1;
return 0;
}
static int
dag_def_live_aliases (def_t *def, void *_d)
{
if (def != _d && def->daglabel)
def->daglabel->live = 1;
return 0;
}
static void
dag_live_aliases(operand_t *op)
{
// FIXME it would be better to propogate the aliasing
if (op->op_type == op_temp
&& (op->o.tempop.alias || op->o.tempop.alias_ops)) {
tempop_visit_all (&op->o.tempop, 1, dag_tempop_live_aliases,
&op->o.tempop);
}
if (op->op_type == op_def
&& (op->o.def->alias || op->o.def->alias_defs)) {
def_visit_all (op->o.def, 1, dag_def_live_aliases, op->o.def);
}
}
static void
dag_make_var_live (set_t *live_vars, operand_t *op)
{
flowvar_t *var = 0;
if (op) {
dag_live_aliases (op);
var = flow_get_var (op);
}
if (var)
set_add (live_vars, var->number);
}
static void
dagnode_attach_label (dagnode_t *n, daglabel_t *l)
{
if (!l->op)
internal_error (0, "attempt to attach operator label to dagnode "
"identifiers");
if (!op_is_identifier (l->op))
internal_error (l->op->expr,
"attempt to attach non-identifer label to dagnode "
"identifiers");
if (l->dagnode) {
// if the node is a leaf, then kill its value so no attempt is made
// to reuse it.
if (l->dagnode->type == st_none) {
l->dagnode->killed = n;
}
dagnode_t *node = l->dagnode;
set_union (n->edges, node->parents);
set_remove (n->edges, n->number);
set_remove (node->identifiers, l->number);
}
l->live = 0; // remove live forcing on assignment
l->dagnode = n;
set_add (n->identifiers, l->number);
dag_kill_aliases (l);
if (n->label->op) {
dag_live_aliases (n->label->op);
}
}
static int
dag_tempop_alias_live (tempop_t *tempop, void *_live_vars)
{
set_t *live_vars = (set_t *) _live_vars;
if (!tempop->flowvar)
return 0;
return set_is_member (live_vars, tempop->flowvar->number);
}
static int
dag_def_alias_live (def_t *def, void *_live_vars)
{
set_t *live_vars = (set_t *) _live_vars;
if (!def->flowvar)
return 0;
return set_is_member (live_vars, def->flowvar->number);
}
static void
dag_remove_dead_vars (dag_t *dag, set_t *live_vars)
{
int i;
for (i = 0; i < dag->num_labels; i++) {
daglabel_t *l = dag->labels[i];
flowvar_t *var;
if (!l->op || !l->dagnode)
continue;
if (l->live) // label forced live (probably via an alias)
continue;
var = flow_get_var (l->op);
if (!var)
continue;
if (set_is_member (dag->flownode->global_vars, var->number))
continue;
if (l->op->op_type == op_def
&& def_visit_all (l->op->o.def, 1, dag_def_alias_live, live_vars))
continue;
if (l->op->op_type == op_temp
&& tempop_visit_all (&l->op->o.tempop, 1, dag_tempop_alias_live,
live_vars))
continue;
if (!set_is_member (live_vars, var->number))
set_remove (l->dagnode->identifiers, l->number);
}
}
static void
dag_sort_visit (dag_t *dag, set_t *visited, int node_index, int *topo)
{
set_iter_t *node_iter;
dagnode_t *node;
if (set_is_member (visited, node_index))
return;
set_add (visited, node_index);
node = dag->nodes[node_index];
for (node_iter = set_first (node->edges); node_iter;
node_iter = set_next (node_iter))
dag_sort_visit (dag, visited, node_iter->element, topo);
node->topo = *topo;
dag->topo[(*topo)++] = node_index;
}
static void
dag_sort_nodes (dag_t *dag)
{
set_iter_t *root_iter;
set_t *visited = set_new ();
int topo = 0;
int *tmp_topo;
if (dag->topo)
free (dag->topo);
dag->topo = alloca (dag->num_nodes * sizeof (int));
for (root_iter = set_first (dag->roots); root_iter;
root_iter = set_next (root_iter))
dag_sort_visit (dag, visited, root_iter->element, &topo);
set_delete (visited);
tmp_topo = malloc (topo * sizeof (int));
memcpy (tmp_topo, dag->topo, topo * sizeof (int));
dag->topo = tmp_topo;
dag->num_topo = topo;
}
static void
dag_kill_nodes (dag_t *dag, dagnode_t *n)
{
int i;
dagnode_t *node;
for (i = 0; i < dag->num_nodes; i++) {
node = dag->nodes[i];
if (node == n->children[1]) {
// assume the pointer does not point to itself. This should be
// reasonable because without casting, only a void pointer can
// point to itself (the required type is recursive).
continue;
}
if (node->label->op && !op_is_identifier (node->label->op)) {
// While constants in the Quake VM can be changed via a pointer,
// doing so would cause much more fun than a simple
// mis-optimization would, so consider them safe from pointer
// operations.
continue;
}
node->killed = n;
}
n->killed = 0;
}
dag_t *
dag_create (flownode_t *flownode)
{
dag_t *dag;
sblock_t *block = flownode->sblock;
statement_t *s;
dagnode_t **nodes;
daglabel_t **labels;
int num_statements = 0;
int num_nodes;
int num_lables;
set_t *live_vars = set_new ();
flush_daglabels ();
// count the number of statements so the number of nodes and labels can be
// guessed
for (s = block->statements; s; s = s->next)
num_statements++;
set_assign (live_vars, flownode->live_vars.out);
dag = new_dag ();
dag->flownode = flownode;
// at most FLOW_OPERANDS per statement
num_nodes = num_statements * FLOW_OPERANDS;
dag->nodes = alloca (num_nodes * sizeof (dagnode_t));
// at most FLOW_OPERANDS per statement, + return + params
num_lables = num_statements * (FLOW_OPERANDS + 1 + 8);
dag->labels = alloca (num_lables * sizeof (daglabel_t));
dag->roots = set_new ();
// do a first pass to ensure all operands have an "x_0" leaf node
// prior do actual dag creation
for (s = block->statements; s; s = s->next) {
operand_t *operands[FLOW_OPERANDS];
dag_make_leafs (dag, s, operands);
}
// actual dag creation
for (s = block->statements; s; s = s->next) {
operand_t *operands[FLOW_OPERANDS];
dagnode_t *n = 0, *children[3] = {0, 0, 0};
daglabel_t *op, *lx;
int i;
dag_make_children (dag, s, operands, children);
if (s->type == st_flow || s->type == st_func) {
for (i = 0; i < 3; i++) {
if (children[i]) {
dag_make_var_live (live_vars, operands[i + 1]);
}
}
}
if (operands[4]) {
// a movep instruction knew what it was reading, so mark that
// as live
dag_make_var_live (live_vars, operands[4]);
}
op = opcode_label (dag, s->opcode, s->expr);
n = children[0];
if (s->type != st_assign) {
if (!(n = dagnode_search (dag, op, children))) {
n = new_node (dag);
n->type = s->type;
n->label = op;
dagnode_add_children (dag, n, operands, children);
dagnode_set_edges (dag, n);
}
}
lx = operand_label (dag, operands[0]);
if (lx && lx->dagnode != n) {
lx->expr = s->expr;
dagnode_attach_label (n, lx);
}
if (n->type == st_ptrassign)
dag_kill_nodes (dag, n);
}
nodes = malloc (dag->num_nodes * sizeof (dagnode_t *));
memcpy (nodes, dag->nodes, dag->num_nodes * sizeof (dagnode_t *));
dag->nodes = nodes;
labels = malloc (dag->num_labels * sizeof (daglabel_t *));
memcpy (labels, dag->labels, dag->num_labels * sizeof (daglabel_t *));
dag->labels = labels;
#if 0
if (options.block_dot.dags) {
flownode->dag = dag;
dump_dot ("raw-dags", flownode->graph, dump_dot_flow_dags);
}
#endif
dag_remove_dead_vars (dag, live_vars);
dag_sort_nodes (dag);
set_delete (live_vars);
return dag;
}
static statement_t *
build_statement (const char *opcode, operand_t **operands, expr_t *expr)
{
int i;
operand_t *op;
statement_t *st = new_statement (st_none, opcode, expr);
for (i = 0; i < 3; i++) {
if ((op = operands[i])) {
while (op->op_type == op_alias)
op = op->o.alias;
if (op->op_type == op_temp) {
while (op->o.tempop.alias)
op = op->o.tempop.alias;
op->o.tempop.users++;
}
}
}
st->opa = operands[0];
st->opb = operands[1];
st->opc = operands[2];
return st;
}
#if 0
static void
dag_calc_node_costs (dagnode_t *dagnode)
{
int i;
for (i = 0; i < 3; i++)
if (dagnode->children[i])
dag_calc_node_costs (dagnode->children[i]);
// if dagnode->a is null, then this is a leaf (as b and c are guaranted to
// be null)
if (!dagnode->children[0]) {
// Because qc vm statements don't mix source and destination operands,
// leaves never need temporary variables.
dagnode->cost = 0;
} else {
int different = 0;
// a non-leaf is guaranteed to have a valid first child
dagnode->cost = dagnode->children[0]->cost;
for (i = 1; i < 3; i++) {
if (dagnode->children[i]
&& dagnode->children[i]->cost != dagnode->cost) {
dagnode->cost = max (dagnode->cost,
dagnode->children[i]->cost);
different = 1;
}
}
if (!different)
dagnode->cost += 1;
}
}
#endif
static operand_t *
fix_op_type (operand_t *op, type_t *type)
{
if (op && op->op_type != op_label && op->type != type)
op = alias_operand (type, op, op->expr);
return op;
}
static operand_t *
make_operand (dag_t *dag, sblock_t *block, const dagnode_t *dagnode, int index)
{
operand_t *op;
op = dagnode->children[index]->value;
op = fix_op_type (op, dagnode->types[index]);
return op;
}
static operand_t *
generate_moves (dag_t *dag, sblock_t *block, dagnode_t *dagnode)
{
set_iter_t *var_iter;
daglabel_t *var;
operand_t *operands[3] = {0, 0, 0};
statement_t *st;
operand_t *dst;
operands[0] = make_operand (dag, block, dagnode, 0);
operands[1] = make_operand (dag, block, dagnode, 1);
dst = operands[0];
for (var_iter = set_first (dagnode->identifiers); var_iter;
var_iter = set_next (var_iter)) {
var = dag->labels[var_iter->element];
operands[2] = var->op;
dst = operands[2];
st = build_statement ("<MOVE>", operands, var->expr);
sblock_add_statement (block, st);
}
return dst;
}
static operand_t *
generate_moveps (dag_t *dag, sblock_t *block, dagnode_t *dagnode)
{
set_iter_t *var_iter;
daglabel_t *var;
operand_t *operands[3] = {0, 0, 0};
statement_t *st;
operand_t *dst = 0;
type_t *type;
int offset = 0;
def_t *dstDef;
operands[0] = make_operand (dag, block, dagnode, 0);
operands[1] = make_operand (dag, block, dagnode, 1);
if (dagnode->children[2]) {
operands[2] = make_operand (dag, block, dagnode, 2);
st = build_statement ("<MOVEP>", operands, dagnode->label->expr);
sblock_add_statement (block, st);
if ((var_iter = set_first (dagnode->identifiers))) {
var = dag->labels[var_iter->element];
dst = var->op;
set_del_iter (var_iter);
}
} else {
for (var_iter = set_first (dagnode->identifiers); var_iter;
var_iter = set_next (var_iter)) {
var = dag->labels[var_iter->element];
dst = var->op;
type = dst->o.def->type;
dstDef = dst->o.def;
if (dstDef->alias) {
offset = dstDef->offset;
dstDef = dstDef->alias;
}
operands[2] = value_operand (new_pointer_val (offset, type, dstDef, 0),
operands[1]->expr);
st = build_statement ("<MOVEP>", operands, var->expr);
sblock_add_statement (block, st);
}
}
return dst;
}
static operand_t *
generate_memsets (dag_t *dag, sblock_t *block, dagnode_t *dagnode)
{
set_iter_t *var_iter;
daglabel_t *var;
operand_t *operands[3] = {0, 0, 0};
statement_t *st;
operand_t *dst;
operands[0] = make_operand (dag, block, dagnode, 0);
operands[1] = make_operand (dag, block, dagnode, 1);
dst = operands[0];
for (var_iter = set_first (dagnode->identifiers); var_iter;
var_iter = set_next (var_iter)) {
var = dag->labels[var_iter->element];
operands[2] = var->op;
dst = operands[2];
st = build_statement ("<MEMSET>", operands, var->expr);
sblock_add_statement (block, st);
}
return dst;
}
static operand_t *
generate_memsetps (dag_t *dag, sblock_t *block, dagnode_t *dagnode)
{
set_iter_t *var_iter;
daglabel_t *var;
operand_t *operands[3] = {0, 0, 0};
statement_t *st;
operand_t *dst = 0;
type_t *type;
int offset = 0;
def_t *dstDef;
operands[0] = make_operand (dag, block, dagnode, 0);
operands[1] = make_operand (dag, block, dagnode, 1);
if (dagnode->children[2]) {
operands[2] = make_operand (dag, block, dagnode, 2);
st = build_statement ("<MEMSETP>", operands, dagnode->label->expr);
sblock_add_statement (block, st);
} else {
for (var_iter = set_first (dagnode->identifiers); var_iter;
var_iter = set_next (var_iter)) {
var = dag->labels[var_iter->element];
dst = var->op;
type = dst->o.def->type;
dstDef = dst->o.def;
if (dstDef->alias) {
offset = dstDef->offset;
dstDef = dstDef->alias;
}
operands[2] = value_operand (new_pointer_val (offset, type, dstDef, 0),
operands[1]->expr);
st = build_statement ("<MEMSETP>", operands, var->expr);
sblock_add_statement (block, st);
}
}
return dst;
}
static operand_t *
generate_assignments (dag_t *dag, sblock_t *block, operand_t *src,
set_iter_t *var_iter, type_t *type)
{
statement_t *st;
operand_t *dst = 0;
operand_t *operands[3] = {0, 0, 0};
daglabel_t *var;
operands[0] = fix_op_type (src, type);
for ( ; var_iter; var_iter = set_next (var_iter)) {
var = dag->labels[var_iter->element];
operands[1] = fix_op_type (var->op, type);
if (!dst)
dst = operands[1];
st = build_statement ("=", operands, var->expr);
sblock_add_statement (block, st);
}
return dst;
}
static void
dag_gencode (dag_t *dag, sblock_t *block, dagnode_t *dagnode)
{
operand_t *operands[3] = {0, 0, 0};
operand_t *dst = 0;
statement_t *st;
set_iter_t *var_iter;
int i;
type_t *type;
switch (dagnode->type) {
case st_none:
if (!dagnode->label->op)
internal_error (0, "non-leaf label in leaf node");
dst = dagnode->label->op;
if ((var_iter = set_first (dagnode->identifiers))) {
type = dst->type;
dst = generate_assignments (dag, block, dst, var_iter, type);
}
break;
case st_expr:
operands[0] = make_operand (dag, block, dagnode, 0);
if (dagnode->children[1])
operands[1] = make_operand (dag, block, dagnode, 1);
type = get_type (dagnode->label->expr);
if (!(var_iter = set_first (dagnode->identifiers))) {
operands[2] = temp_operand (get_type (dagnode->label->expr),
dagnode->label->expr);
} else {
daglabel_t *var = dag->labels[var_iter->element];
operands[2] = fix_op_type (var->op, type);
var_iter = set_next (var_iter);
}
dst = operands[2];
st = build_statement (dagnode->label->opcode, operands,
dagnode->label->expr);
sblock_add_statement (block, st);
generate_assignments (dag, block, operands[2], var_iter, type);
break;
case st_assign:
internal_error (0, "unexpected assignment node");
case st_ptrassign:
operands[0] = make_operand (dag, block, dagnode, 0);
operands[1] = make_operand (dag, block, dagnode, 1);
if (dagnode->children[2])
operands[2] = make_operand (dag, block, dagnode, 2);
st = build_statement (dagnode->label->opcode, operands,
dagnode->label->expr);
sblock_add_statement (block, st);
// the source location is suitable for use in other nodes
dst = operands[0];
break;
case st_move:
dst = generate_moves (dag, block, dagnode);
break;
case st_ptrmove:
dst = generate_moveps (dag, block, dagnode);
break;
case st_memset:
dst = generate_memsets (dag, block, dagnode);
break;
case st_ptrmemset:
dst = generate_memsetps (dag, block, dagnode);
break;
case st_state:
case st_func:
for (i = 0; i < 3; i++)
if (dagnode->children[i])
operands[i] = make_operand (dag, block, dagnode, i);
st = build_statement (dagnode->label->opcode, operands,
dagnode->label->expr);
sblock_add_statement (block, st);
break;
case st_flow:
operands[0] = make_operand (dag, block, dagnode, 0);
if (dagnode->children[1])
operands[1] = make_operand (dag, block, dagnode, 1);
st = build_statement (dagnode->label->opcode, operands,
dagnode->label->expr);
sblock_add_statement (block, st);
break;
}
dagnode->value = dst;
}
void
dag_remove_dead_nodes (dag_t *dag)
{
int added_root;
set_iter_t *root_i, *child_i;
dagnode_t *node, *child;
do {
added_root = 0;
for (root_i = set_first (dag->roots); root_i;
root_i = set_next (root_i)) {
node = dag->nodes[root_i->element];
// only st_none (leaf nodes), st_expr and st_move can become
// dead nodes (no live vars attached).
if (node->type != st_none && node->type != st_expr
&& node->type != st_move)
continue;
if (!set_is_empty (node->identifiers))
continue;
// MOVEP with a variable destination pointer is never dead
if (node->type == st_move && node->children[2])
continue;
set_remove (dag->roots, node->number);
for (child_i = set_first (node->edges); child_i;
child_i = set_next (child_i)) {
child = dag->nodes[child_i->element];
if (!set_is_member (child->parents, node->number))
continue; // not really a child (dependency edge)
set_remove (child->parents, node->number);
if (set_is_empty (child->parents)) {
set_add (dag->roots, child->number);
added_root = 1;
}
}
}
} while (added_root);
// clean up any stray edges that point to removed nodes
for (int i = 0; i < dag->num_nodes; i++) {
node = dag->nodes[i];
for (child_i = set_first (node->edges); child_i;
child_i = set_next (child_i)) {
child = dag->nodes[child_i->element];
if (!set_is_member (dag->roots, child->number)
&& set_is_empty (child->parents)) {
set_remove (node->edges, child->number);
}
}
}
dag_sort_nodes (dag);
}
void
dag_generate (dag_t *dag, sblock_t *block)
{
int i;
for (i = 0; i < dag->num_topo; i++)
dag_gencode (dag, block, dag->nodes[dag->topo[i]]);
}