/* 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);
}
/* Find list of values for that we want to measure histograms. */
static void
rtl_find_values_to_profile (histogram_values *values)
{
rtx insn;
unsigned i, libcall_level;
life_analysis (NULL, PROP_DEATH_NOTES);
*values = VEC_alloc (histogram_value, 0);
libcall_level = 0;
for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
{
if (find_reg_note (insn, REG_LIBCALL, NULL_RTX))
libcall_level++;
/* Do not instrument values inside libcalls (we are going to split block
due to instrumentation, and libcall blocks should be local to a single
basic block). */
if (!libcall_level)
insn_values_to_profile (insn, values);
if (find_reg_note (insn, REG_RETVAL, NULL_RTX))
{
gcc_assert (libcall_level > 0);
libcall_level--;
}
}
gcc_assert (libcall_level == 0);
for (i = 0; i < VEC_length (histogram_value, *values); i++)
{
histogram_value hist = VEC_index (histogram_value, *values, i);
switch (hist->type)
{
case HIST_TYPE_INTERVAL:
if (dump_file)
fprintf (dump_file,
"Interval counter for insn %d, range %d -- %d.\n",
INSN_UID ((rtx)hist->insn),
hist->hdata.intvl.int_start,
(hist->hdata.intvl.int_start
+ hist->hdata.intvl.steps - 1));
hist->n_counters = hist->hdata.intvl.steps +
(hist->hdata.intvl.may_be_less ? 1 : 0) +
(hist->hdata.intvl.may_be_more ? 1 : 0);
break;
case HIST_TYPE_POW2:
if (dump_file)
fprintf (dump_file,
"Pow2 counter for insn %d.\n",
INSN_UID ((rtx)hist->insn));
hist->n_counters
= GET_MODE_BITSIZE (hist->mode)
+ (hist->hdata.pow2.may_be_other ? 1 : 0);
break;
case HIST_TYPE_SINGLE_VALUE:
if (dump_file)
fprintf (dump_file,
"Single value counter for insn %d.\n",
INSN_UID ((rtx)hist->insn));
hist->n_counters = 3;
break;
case HIST_TYPE_CONST_DELTA:
if (dump_file)
fprintf (dump_file,
"Constant delta counter for insn %d.\n",
INSN_UID ((rtx)hist->insn));
hist->n_counters = 4;
break;
default:
abort ();
}
}
allocate_reg_info (max_reg_num (), FALSE, FALSE);
}
