/* update bb and life_info after spilling
* this saves 4 costy routines
* NOTE {lhs_,}use_count are not set again, this is save, when no
* further optimization pass follows
*
*/
static void
update_life(Parrot_Interp interpreter, IMC_Unit * unit, Instruction *ins,
SymReg *r, int needs_fetch, int needs_store, int add)
{
Life_range *l;
int i;
Instruction *ins2;
Basic_block **bb_list = unit->bb_list;
#if IMC_TRACE
fprintf(stderr, "reg_alloc.c: update_life(%s)\n", r->name);
#endif
for (i = 0, ins2 = unit->instructions; ins2; ins2 = ins2->next) {
ins2->index = i++;
}
/* add this sym to reglist, if not there */
if (add) {
unit->reglist = realloc(unit->reglist, (n_symbols + 1) * sizeof(SymReg *));
unit->reglist[n_symbols++] = r;
}
r->first_ins = r->last_ins = ins;
if (needs_fetch) {
/* prev instructions is a fetch then and the first usage of this reg */
r->first_ins = ins->prev;
/* if this ins was the first of a BB, then the fetch is the
* first ins then
*/
if (ins == bb_list[ins->bbindex]->start)
bb_list[ins->bbindex]->start = ins->prev;
}
if (needs_store) {
/* next ins is a store then, and ends life of this reg */
r->last_ins = ins->next;
if (ins == bb_list[ins->bbindex]->end)
bb_list[ins->bbindex]->end = ins->next;
}
/* now set life_info */
free_life_info(unit, r);
r->life_info = calloc(unit->n_basic_blocks,
sizeof(Life_range*));
for (i=0; i < unit->n_basic_blocks; i++)
make_life_range(r, i);
l = r->life_info[ins->bbindex];
l->first_ins = r->first_ins;
l->last_ins = r->last_ins;
if (IMCC_INFO(interpreter)->debug & DEBUG_IMC) {
dump_instructions(unit);
dump_symreg(unit);
}
}
void
backend_shader::dump_instructions()
{
dump_instructions(NULL);
}
/* imc_reg_alloc is the main loop of the allocation algorithm. It operates
* on a single compilation unit at a time.
*/
void
imc_reg_alloc(struct Parrot_Interp *interpreter, IMC_Unit * unit)
{
int to_spill;
int todo, first;
if (!unit)
return;
if (!optimizer_level && pasm_file)
return;
init_tables(interpreter);
allocated = 0;
#if IMC_TRACE
fprintf(stderr, "reg_alloc.c: imc_reg_alloc\n");
if (unit->instructions->r[1] && unit->instructions->r[1]->pcc_sub) {
fprintf(stderr, "img_reg_alloc: pcc_sub (nargs = %d)\n",
unit->instructions->r[1]->pcc_sub->nargs);
}
#endif
debug(interpreter, DEBUG_IMC, "\n------------------------\n");
debug(interpreter, DEBUG_IMC, "processing sub %s\n", function);
debug(interpreter, DEBUG_IMC, "------------------------\n\n");
if (IMCC_INFO(interpreter)->verbose ||
(IMCC_INFO(interpreter)->debug & DEBUG_IMC))
imc_stat_init(unit);
/* consecutive labels, if_branch, unused_labels ... */
pre_optimize(interpreter, unit);
if (optimizer_level == OPT_PRE && pasm_file)
return;
nodeStack = imcstack_new();
unit->n_spilled = 0;
todo = first = 1;
while (todo) {
find_basic_blocks(interpreter, unit, first);
build_cfg(interpreter, unit);
if (first && (IMCC_INFO(interpreter)->debug & DEBUG_CFG))
dump_cfg(unit);
first = 0;
todo = cfg_optimize(interpreter, unit);
}
todo = first = 1;
while (todo) {
if (!first) {
find_basic_blocks(interpreter, unit, 0);
build_cfg(interpreter, unit);
}
first = 0;
compute_dominators(interpreter, unit);
find_loops(interpreter, unit);
build_reglist(interpreter, unit);
life_analysis(interpreter, unit);
/* optimize, as long as there is something to do */
if (dont_optimize)
todo = 0;
else {
todo = optimize(interpreter, unit);
if (todo)
pre_optimize(interpreter, unit);
}
}
todo = 1;
#if !DOIT_AGAIN_SAM
build_interference_graph(interpreter, unit);
#endif
while (todo) {
#if DOIT_AGAIN_SAM
build_interference_graph(interpreter, unit);
#endif
if (optimizer_level & OPT_SUB)
allocate_wanted_regs(unit);
compute_spilling_costs(interpreter, unit);
#ifdef DO_SIMPLIFY
/* simplify until no changes can be made */
while (simplify(unit)) {}
#endif
order_spilling(unit); /* put the remaining items on stack */
to_spill = try_allocate(interpreter, unit);
allocated = 1;
if ( to_spill >= 0 ) {
allocated = 0;
spill(interpreter, unit, to_spill);
/*
* build the new cfg/reglist on the fly in spill() and
* do life analysis there for only the involved regs
*/
#if DOIT_AGAIN_SAM
find_basic_blocks(interpreter, unit, 0);
build_cfg(interpreter, unit);
build_reglist(interpreter, unit);
life_analysis(interpreter);
#endif
}
else {
/* the process is finished */
todo = 0;
}
}
if (optimizer_level & OPT_SUB)
sub_optimize(interpreter, unit);
if (IMCC_INFO(interpreter)->debug & DEBUG_IMC)
dump_instructions(unit);
if (IMCC_INFO(interpreter)->verbose ||
(IMCC_INFO(interpreter)->debug & DEBUG_IMC))
print_stat(interpreter, unit);
imcstack_free(nodeStack);
}