#include "config.h"
#include "system.h"
#include "tree.h"
#include "rtl.h"
#include "tm_p.h"
#include "hard-reg-set.h"
#include "basic-block.h"
#include "insn-config.h"
#include "regs.h"
#include "flags.h"
#include "output.h"
#include "function.h"
#include "except.h"
#include "toplev.h"
#include "recog.h"
#include "expr.h"
#include "predict.h"
#include "profile.h"
#include "real.h"
#include "params.h"
#include "target.h"
#include "loop.h"
static REAL_VALUE_TYPE real_zero, real_one, real_almost_one, real_br_prob_base,
real_inv_br_prob_base, real_one_half, real_bb_freq_max;
#define PROB_VERY_UNLIKELY (REG_BR_PROB_BASE / 10 - 1)
#define PROB_EVEN (REG_BR_PROB_BASE / 2)
#define PROB_VERY_LIKELY (REG_BR_PROB_BASE - PROB_VERY_UNLIKELY)
#define PROB_ALWAYS (REG_BR_PROB_BASE)
static bool predicted_by_p PARAMS ((basic_block,
enum br_predictor));
static void combine_predictions_for_insn PARAMS ((rtx, basic_block));
static void dump_prediction PARAMS ((enum br_predictor, int,
basic_block, int));
static void estimate_loops_at_level PARAMS ((struct loop *loop));
static void propagate_freq PARAMS ((struct loop *));
static void estimate_bb_frequencies PARAMS ((struct loops *));
static void counts_to_freqs PARAMS ((void));
static void process_note_predictions PARAMS ((basic_block, int *,
dominance_info,
dominance_info));
static void process_note_prediction PARAMS ((basic_block, int *,
dominance_info,
dominance_info, int, int));
static bool last_basic_block_p PARAMS ((basic_block));
static void compute_function_frequency PARAMS ((void));
static void choose_function_section PARAMS ((void));
static bool can_predict_insn_p PARAMS ((rtx));
struct predictor_info
{
const char *const name;
const int hitrate;
const int flags;
};
#define PRED_FLAG_FIRST_MATCH 1
#define HITRATE(VAL) ((int) ((VAL) * REG_BR_PROB_BASE + 50) / 100)
#define DEF_PREDICTOR(ENUM, NAME, HITRATE, FLAGS) {NAME, HITRATE, FLAGS},
static const struct predictor_info predictor_info[]= {
#include "predict.def"
{NULL, 0, 0}
};
#undef DEF_PREDICTOR
bool
maybe_hot_bb_p (bb)
basic_block bb;
{
if (profile_info.count_profiles_merged
&& flag_branch_probabilities
&& (bb->count
< profile_info.max_counter_in_program
/ PARAM_VALUE (HOT_BB_COUNT_FRACTION)))
return false;
if (bb->frequency < BB_FREQ_MAX / PARAM_VALUE (HOT_BB_FREQUENCY_FRACTION))
return false;
return true;
}
bool
probably_cold_bb_p (bb)
basic_block bb;
{
if (profile_info.count_profiles_merged
&& flag_branch_probabilities
&& (bb->count
< profile_info.max_counter_in_program
/ PARAM_VALUE (HOT_BB_COUNT_FRACTION)))
return true;
if (bb->frequency < BB_FREQ_MAX / PARAM_VALUE (HOT_BB_FREQUENCY_FRACTION))
return true;
return false;
}
bool
probably_never_executed_bb_p (bb)
basic_block bb;
{
if (profile_info.count_profiles_merged
&& flag_branch_probabilities)
return ((bb->count + profile_info.count_profiles_merged / 2)
/ profile_info.count_profiles_merged) == 0;
return false;
}
static bool
predicted_by_p (bb, predictor)
basic_block bb;
enum br_predictor predictor;
{
rtx note;
if (!INSN_P (bb->end))
return false;
for (note = REG_NOTES (bb->end); note; note = XEXP (note, 1))
if (REG_NOTE_KIND (note) == REG_BR_PRED
&& INTVAL (XEXP (XEXP (note, 0), 0)) == (int)predictor)
return true;
return false;
}
void
predict_insn (insn, predictor, probability)
rtx insn;
int probability;
enum br_predictor predictor;
{
if (!any_condjump_p (insn))
abort ();
if (!flag_guess_branch_prob)
return;
REG_NOTES (insn)
= gen_rtx_EXPR_LIST (REG_BR_PRED,
gen_rtx_CONCAT (VOIDmode,
GEN_INT ((int) predictor),
GEN_INT ((int) probability)),
REG_NOTES (insn));
}
void
predict_insn_def (insn, predictor, taken)
rtx insn;
enum br_predictor predictor;
enum prediction taken;
{
int probability = predictor_info[(int) predictor].hitrate;
if (taken != TAKEN)
probability = REG_BR_PROB_BASE - probability;
predict_insn (insn, predictor, probability);
}
void
predict_edge (e, predictor, probability)
edge e;
int probability;
enum br_predictor predictor;
{
rtx last_insn;
last_insn = e->src->end;
if (!any_condjump_p (last_insn))
return;
if (e->flags & EDGE_FALLTHRU)
probability = REG_BR_PROB_BASE - probability;
predict_insn (last_insn, predictor, probability);
}
static bool
can_predict_insn_p (insn)
rtx insn;
{
return (GET_CODE (insn) == JUMP_INSN
&& any_condjump_p (insn)
&& BLOCK_FOR_INSN (insn)->succ->succ_next);
}
void
predict_edge_def (e, predictor, taken)
edge e;
enum br_predictor predictor;
enum prediction taken;
{
int probability = predictor_info[(int) predictor].hitrate;
if (taken != TAKEN)
probability = REG_BR_PROB_BASE - probability;
predict_edge (e, predictor, probability);
}
void
invert_br_probabilities (insn)
rtx insn;
{
rtx note;
for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
if (REG_NOTE_KIND (note) == REG_BR_PROB)
XEXP (note, 0) = GEN_INT (REG_BR_PROB_BASE - INTVAL (XEXP (note, 0)));
else if (REG_NOTE_KIND (note) == REG_BR_PRED)
XEXP (XEXP (note, 0), 1)
= GEN_INT (REG_BR_PROB_BASE - INTVAL (XEXP (XEXP (note, 0), 1)));
}
static void
dump_prediction (predictor, probability, bb, used)
enum br_predictor predictor;
int probability;
basic_block bb;
int used;
{
edge e = bb->succ;
if (!rtl_dump_file)
return;
while (e && (e->flags & EDGE_FALLTHRU))
e = e->succ_next;
fprintf (rtl_dump_file, " %s heuristics%s: %.1f%%",
predictor_info[predictor].name,
used ? "" : " (ignored)", probability * 100.0 / REG_BR_PROB_BASE);
if (bb->count)
{
fprintf (rtl_dump_file, " exec ");
fprintf (rtl_dump_file, HOST_WIDEST_INT_PRINT_DEC, bb->count);
if (e)
{
fprintf (rtl_dump_file, " hit ");
fprintf (rtl_dump_file, HOST_WIDEST_INT_PRINT_DEC, e->count);
fprintf (rtl_dump_file, " (%.1f%%)", e->count * 100.0 / bb->count);
}
}
fprintf (rtl_dump_file, "\n");
}
static void
combine_predictions_for_insn (insn, bb)
rtx insn;
basic_block bb;
{
rtx prob_note = find_reg_note (insn, REG_BR_PROB, 0);
rtx *pnote = ®_NOTES (insn);
rtx note;
int best_probability = PROB_EVEN;
int best_predictor = END_PREDICTORS;
int combined_probability = REG_BR_PROB_BASE / 2;
int d;
bool first_match = false;
bool found = false;
if (rtl_dump_file)
fprintf (rtl_dump_file, "Predictions for insn %i bb %i\n", INSN_UID (insn),
bb->index);
for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
if (REG_NOTE_KIND (note) == REG_BR_PRED)
{
int predictor = INTVAL (XEXP (XEXP (note, 0), 0));
int probability = INTVAL (XEXP (XEXP (note, 0), 1));
found = true;
if (best_predictor > predictor)
best_probability = probability, best_predictor = predictor;
d = (combined_probability * probability
+ (REG_BR_PROB_BASE - combined_probability)
* (REG_BR_PROB_BASE - probability));
if (d == 0)
combined_probability = REG_BR_PROB_BASE / 2;
else
combined_probability = (((double) combined_probability) * probability
* REG_BR_PROB_BASE / d + 0.5);
}
if (predictor_info [best_predictor].flags & PRED_FLAG_FIRST_MATCH)
first_match = true;
if (!found)
dump_prediction (PRED_NO_PREDICTION, combined_probability, bb, true);
else
{
dump_prediction (PRED_DS_THEORY, combined_probability, bb, !first_match);
dump_prediction (PRED_FIRST_MATCH, best_probability, bb, first_match);
}
if (first_match)
combined_probability = best_probability;
dump_prediction (PRED_COMBINED, combined_probability, bb, true);
while (*pnote)
{
if (REG_NOTE_KIND (*pnote) == REG_BR_PRED)
{
int predictor = INTVAL (XEXP (XEXP (*pnote, 0), 0));
int probability = INTVAL (XEXP (XEXP (*pnote, 0), 1));
dump_prediction (predictor, probability, bb,
!first_match || best_predictor == predictor);
*pnote = XEXP (*pnote, 1);
}
else
pnote = &XEXP (*pnote, 1);
}
if (!prob_note)
{
REG_NOTES (insn)
= gen_rtx_EXPR_LIST (REG_BR_PROB,
GEN_INT (combined_probability), REG_NOTES (insn));
if (bb->succ->succ_next)
{
BRANCH_EDGE (bb)->probability = combined_probability;
FALLTHRU_EDGE (bb)->probability
= REG_BR_PROB_BASE - combined_probability;
}
}
}
void
estimate_probability (loops_info)
struct loops *loops_info;
{
dominance_info dominators, post_dominators;
basic_block bb;
int i;
connect_infinite_loops_to_exit ();
dominators = calculate_dominance_info (CDI_DOMINATORS);
post_dominators = calculate_dominance_info (CDI_POST_DOMINATORS);
for (i = 1; i < loops_info->num; i++)
{
basic_block bb, *bbs;
int j;
int exits;
struct loop *loop = loops_info->parray[i];
flow_loop_scan (loops_info, loop, LOOP_EXIT_EDGES);
exits = loop->num_exits;
bbs = get_loop_body (loop);
for (j = 0; j < loop->num_nodes; j++)
{
int header_found = 0;
edge e;
bb = bbs[j];
if (!can_predict_insn_p (bb->end)
|| predicted_by_p (bb, PRED_CONTINUE))
continue;
for (e = bb->succ; e; e = e->succ_next)
if (e->dest == loop->header
&& e->src == loop->latch)
{
header_found = 1;
predict_edge_def (e, PRED_LOOP_BRANCH, TAKEN);
}
if (!header_found)
for (e = bb->succ; e; e = e->succ_next)
if (e->dest->index < 0
|| !flow_bb_inside_loop_p (loop, e->dest))
predict_edge
(e, PRED_LOOP_EXIT,
(REG_BR_PROB_BASE
- predictor_info [(int) PRED_LOOP_EXIT].hitrate)
/ exits);
}
}
FOR_EACH_BB (bb)
{
rtx last_insn = bb->end;
rtx cond, earliest;
edge e;
if (! can_predict_insn_p (last_insn))
continue;
for (e = bb->succ; e; e = e->succ_next)
{
if ((e->dest == EXIT_BLOCK_PTR
|| (e->dest->succ && !e->dest->succ->succ_next
&& e->dest->succ->dest == EXIT_BLOCK_PTR))
&& !predicted_by_p (bb, PRED_NULL_RETURN)
&& !predicted_by_p (bb, PRED_CONST_RETURN)
&& !predicted_by_p (bb, PRED_NEGATIVE_RETURN)
&& !last_basic_block_p (e->dest))
predict_edge_def (e, PRED_EARLY_RETURN, TAKEN);
if (e->dest != EXIT_BLOCK_PTR && e->dest != bb
&& dominated_by_p (dominators, e->dest, e->src)
&& !dominated_by_p (post_dominators, e->src, e->dest))
{
rtx insn;
for (insn = e->dest->head; insn != NEXT_INSN (e->dest->end);
insn = NEXT_INSN (insn))
if (GET_CODE (insn) == CALL_INSN
&& ! CONST_OR_PURE_CALL_P (insn))
{
predict_edge_def (e, PRED_CALL, NOT_TAKEN);
break;
}
}
}
cond = get_condition (last_insn, &earliest);
if (! cond)
continue;
if (GET_RTX_CLASS (GET_CODE (cond)) == '<'
&& ((REG_P (XEXP (cond, 0)) && REG_POINTER (XEXP (cond, 0)))
|| (REG_P (XEXP (cond, 1)) && REG_POINTER (XEXP (cond, 1)))))
{
if (GET_CODE (cond) == EQ)
predict_insn_def (last_insn, PRED_POINTER, NOT_TAKEN);
else if (GET_CODE (cond) == NE)
predict_insn_def (last_insn, PRED_POINTER, TAKEN);
}
else
switch (GET_CODE (cond))
{
case CONST_INT:
predict_insn_def (last_insn, PRED_UNCONDITIONAL,
cond == const0_rtx ? NOT_TAKEN : TAKEN);
break;
case EQ:
case UNEQ:
if (FLOAT_MODE_P (GET_MODE (XEXP (cond, 0))))
;
else if (XEXP (cond, 1) == const0_rtx
|| XEXP (cond, 0) == const0_rtx)
;
else
predict_insn_def (last_insn, PRED_OPCODE_NONEQUAL, NOT_TAKEN);
break;
case NE:
case LTGT:
if (FLOAT_MODE_P (GET_MODE (XEXP (cond, 0))))
;
else if (XEXP (cond, 1) == const0_rtx
|| XEXP (cond, 0) == const0_rtx)
;
else
predict_insn_def (last_insn, PRED_OPCODE_NONEQUAL, TAKEN);
break;
case ORDERED:
predict_insn_def (last_insn, PRED_FPOPCODE, TAKEN);
break;
case UNORDERED:
predict_insn_def (last_insn, PRED_FPOPCODE, NOT_TAKEN);
break;
case LE:
case LT:
if (XEXP (cond, 1) == const0_rtx || XEXP (cond, 1) == const1_rtx
|| XEXP (cond, 1) == constm1_rtx)
predict_insn_def (last_insn, PRED_OPCODE_POSITIVE, NOT_TAKEN);
break;
case GE:
case GT:
if (XEXP (cond, 1) == const0_rtx || XEXP (cond, 1) == const1_rtx
|| XEXP (cond, 1) == constm1_rtx)
predict_insn_def (last_insn, PRED_OPCODE_POSITIVE, TAKEN);
break;
default:
break;
}
}
FOR_EACH_BB (bb)
if (GET_CODE (bb->end) == JUMP_INSN
&& any_condjump_p (bb->end)
&& bb->succ->succ_next != NULL)
combine_predictions_for_insn (bb->end, bb);
free_dominance_info (post_dominators);
free_dominance_info (dominators);
remove_fake_edges ();
estimate_bb_frequencies (loops_info);
}
void
expected_value_to_br_prob ()
{
rtx insn, cond, ev = NULL_RTX, ev_reg = NULL_RTX;
for (insn = get_insns (); insn ; insn = NEXT_INSN (insn))
{
switch (GET_CODE (insn))
{
case NOTE:
if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EXPECTED_VALUE)
{
ev = NOTE_EXPECTED_VALUE (insn);
ev_reg = XEXP (ev, 0);
delete_insn (insn);
}
continue;
case CODE_LABEL:
ev = NULL_RTX;
continue;
case JUMP_INSN:
if (GET_CODE (insn) != JUMP_INSN || ev == NULL_RTX
|| ! any_condjump_p (insn))
continue;
break;
default:
if (ev && reg_set_p (ev_reg, insn))
ev = NULL_RTX;
continue;
}
cond = XEXP (SET_SRC (pc_set (insn)), 0);
cond = canonicalize_condition (insn, cond, 0, NULL, ev_reg);
if (! cond || XEXP (cond, 0) != ev_reg
|| GET_CODE (XEXP (cond, 1)) != CONST_INT)
continue;
cond = gen_rtx_fmt_ee (GET_CODE (cond), VOIDmode,
XEXP (ev, 1), XEXP (cond, 1));
cond = simplify_rtx (cond);
if (cond != const_true_rtx && cond != const0_rtx)
abort ();
predict_insn_def (insn, PRED_BUILTIN_EXPECT,
cond == const_true_rtx ? TAKEN : NOT_TAKEN);
}
}
static bool
last_basic_block_p (bb)
basic_block bb;
{
if (bb == EXIT_BLOCK_PTR)
return false;
return (bb->next_bb == EXIT_BLOCK_PTR
|| (bb->next_bb->next_bb == EXIT_BLOCK_PTR
&& bb->succ && !bb->succ->succ_next
&& bb->succ->dest->next_bb == EXIT_BLOCK_PTR));
}
static void
process_note_prediction (bb, heads, dominators, post_dominators, pred, flags)
basic_block bb;
int *heads;
dominance_info dominators;
dominance_info post_dominators;
int pred;
int flags;
{
edge e;
int y;
bool taken;
taken = flags & IS_TAKEN;
if (heads[bb->index] < 0)
{
basic_block ai = bb;
basic_block next_ai = get_immediate_dominator (dominators, bb);
int head;
while (heads[next_ai->index] < 0)
{
if (!dominated_by_p (post_dominators, next_ai, bb))
break;
heads[next_ai->index] = ai->index;
ai = next_ai;
next_ai = get_immediate_dominator (dominators, next_ai);
}
if (!dominated_by_p (post_dominators, next_ai, bb))
head = next_ai->index;
else
head = heads[next_ai->index];
while (next_ai != bb)
{
next_ai = ai;
if (heads[ai->index] == ENTRY_BLOCK)
ai = ENTRY_BLOCK_PTR;
else
ai = BASIC_BLOCK (heads[ai->index]);
heads[next_ai->index] = head;
}
}
y = heads[bb->index];
if (y == last_basic_block || !can_predict_insn_p (BASIC_BLOCK (y)->end))
return;
for (e = BASIC_BLOCK (y)->succ; e; e = e->succ_next)
if (e->dest->index >= 0
&& dominated_by_p (post_dominators, e->dest, bb))
predict_edge_def (e, pred, taken);
}
static void
process_note_predictions (bb, heads, dominators, post_dominators)
basic_block bb;
int *heads;
dominance_info dominators;
dominance_info post_dominators;
{
rtx insn;
edge e;
int contained_noreturn_call = 0;
int was_bb_head = 0;
int noreturn_block = 1;
for (insn = bb->end; insn;
was_bb_head |= (insn == bb->head), insn = PREV_INSN (insn))
{
if (GET_CODE (insn) != NOTE)
{
if (was_bb_head)
break;
else
{
if (GET_CODE (insn) == CALL_INSN
&& find_reg_note (insn, REG_NORETURN, NULL))
contained_noreturn_call = 1;
continue;
}
}
if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_PREDICTION)
{
int alg = (int) NOTE_PREDICTION_ALG (insn);
process_note_prediction (bb,
heads,
dominators,
post_dominators,
alg, (int) NOTE_PREDICTION_FLAGS (insn));
delete_insn (insn);
}
}
for (e = bb->succ; e; e = e->succ_next)
if (!(e->flags & EDGE_FAKE))
noreturn_block = 0;
if (contained_noreturn_call)
{
process_note_prediction (bb,
heads,
dominators,
post_dominators, PRED_NORETURN, NOT_TAKEN);
}
}
void
note_prediction_to_br_prob ()
{
basic_block bb;
dominance_info post_dominators, dominators;
int *heads;
add_noreturn_fake_exit_edges ();
connect_infinite_loops_to_exit ();
post_dominators = calculate_dominance_info (CDI_POST_DOMINATORS);
dominators = calculate_dominance_info (CDI_DOMINATORS);
heads = xmalloc (sizeof (int) * last_basic_block);
memset (heads, -1, sizeof (int) * last_basic_block);
heads[ENTRY_BLOCK_PTR->next_bb->index] = last_basic_block;
FOR_EACH_BB (bb)
process_note_predictions (bb, heads, dominators, post_dominators);
free_dominance_info (post_dominators);
free_dominance_info (dominators);
free (heads);
remove_fake_edges ();
}
typedef struct block_info_def
{
REAL_VALUE_TYPE frequency;
basic_block next;
int tovisit:1;
int npredecessors;
} *block_info;
typedef struct edge_info_def
{
REAL_VALUE_TYPE back_edge_prob;
int back_edge:1;
} *edge_info;
#define BLOCK_INFO(B) ((block_info) (B)->aux)
#define EDGE_INFO(E) ((edge_info) (E)->aux)
static void
propagate_freq (loop)
struct loop *loop;
{
basic_block head = loop->header;
basic_block bb;
basic_block last;
edge e;
basic_block nextbb;
FOR_EACH_BB (bb)
{
if (BLOCK_INFO (bb)->tovisit)
{
int count = 0;
for (e = bb->pred; e; e = e->pred_next)
if (BLOCK_INFO (e->src)->tovisit && !(e->flags & EDGE_DFS_BACK))
count++;
else if (BLOCK_INFO (e->src)->tovisit
&& rtl_dump_file && !EDGE_INFO (e)->back_edge)
fprintf (rtl_dump_file,
"Irreducible region hit, ignoring edge to %i->%i\n",
e->src->index, bb->index);
BLOCK_INFO (bb)->npredecessors = count;
}
}
memcpy (&BLOCK_INFO (head)->frequency, &real_one, sizeof (real_one));
last = head;
for (bb = head; bb; bb = nextbb)
{
REAL_VALUE_TYPE cyclic_probability, frequency;
memcpy (&cyclic_probability, &real_zero, sizeof (real_zero));
memcpy (&frequency, &real_zero, sizeof (real_zero));
nextbb = BLOCK_INFO (bb)->next;
BLOCK_INFO (bb)->next = NULL;
if (bb != head)
{
#ifdef ENABLE_CHECKING
for (e = bb->pred; e; e = e->pred_next)
if (BLOCK_INFO (e->src)->tovisit && !(e->flags & EDGE_DFS_BACK))
abort ();
#endif
for (e = bb->pred; e; e = e->pred_next)
if (EDGE_INFO (e)->back_edge)
{
REAL_ARITHMETIC (cyclic_probability, PLUS_EXPR,
cyclic_probability,
EDGE_INFO (e)->back_edge_prob);
}
else if (!(e->flags & EDGE_DFS_BACK))
{
REAL_VALUE_TYPE tmp;
REAL_VALUE_FROM_INT (tmp, e->probability, 0,
TYPE_MODE (double_type_node));
REAL_ARITHMETIC (tmp, MULT_EXPR, tmp,
BLOCK_INFO (e->src)->frequency);
REAL_ARITHMETIC (tmp, MULT_EXPR, tmp, real_inv_br_prob_base);
REAL_ARITHMETIC (frequency, PLUS_EXPR, frequency, tmp);
}
if (REAL_VALUES_IDENTICAL (cyclic_probability, real_zero))
memcpy (&BLOCK_INFO (bb)->frequency, &frequency, sizeof (frequency));
else
{
if (REAL_VALUES_LESS (real_almost_one, cyclic_probability))
memcpy (&cyclic_probability, &real_almost_one, sizeof (real_zero));
REAL_ARITHMETIC (cyclic_probability, MINUS_EXPR, real_one,
cyclic_probability);
REAL_ARITHMETIC (BLOCK_INFO (bb)->frequency,
RDIV_EXPR, frequency, cyclic_probability);
}
}
BLOCK_INFO (bb)->tovisit = 0;
for (e = bb->succ; e; e = e->succ_next)
if (e->dest == head)
{
REAL_VALUE_TYPE tmp;
REAL_VALUE_FROM_INT (tmp, e->probability, 0,
TYPE_MODE (double_type_node));
REAL_ARITHMETIC (tmp, MULT_EXPR, tmp,
BLOCK_INFO (bb)->frequency);
REAL_ARITHMETIC (EDGE_INFO (e)->back_edge_prob,
MULT_EXPR, tmp, real_inv_br_prob_base);
}
for (e = bb->succ; e; e = e->succ_next)
if (!(e->flags & EDGE_DFS_BACK)
&& BLOCK_INFO (e->dest)->npredecessors)
{
BLOCK_INFO (e->dest)->npredecessors--;
if (!BLOCK_INFO (e->dest)->npredecessors)
{
if (!nextbb)
nextbb = e->dest;
else
BLOCK_INFO (last)->next = e->dest;
last = e->dest;
}
}
}
}
static void
estimate_loops_at_level (first_loop)
struct loop *first_loop;
{
struct loop *loop;
for (loop = first_loop; loop; loop = loop->next)
{
edge e;
basic_block *bbs;
int i;
estimate_loops_at_level (loop->inner);
if (loop->latch->succ)
{
e = loop_latch_edge (loop);
EDGE_INFO (e)->back_edge = 1;
}
bbs = get_loop_body (loop);
for (i = 0; i < loop->num_nodes; i++)
BLOCK_INFO (bbs[i])->tovisit = 1;
free (bbs);
propagate_freq (loop);
}
}
static void
counts_to_freqs ()
{
HOST_WIDEST_INT count_max = 1;
basic_block bb;
FOR_EACH_BB (bb)
count_max = MAX (bb->count, count_max);
FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, NULL, next_bb)
bb->frequency = (bb->count * BB_FREQ_MAX + count_max / 2) / count_max;
}
bool
expensive_function_p (threshold)
int threshold;
{
unsigned int sum = 0;
basic_block bb;
unsigned int limit;
if (threshold > BB_FREQ_MAX)
abort ();
if (ENTRY_BLOCK_PTR->frequency == 0)
return true;
limit = ENTRY_BLOCK_PTR->frequency * threshold;
FOR_EACH_BB (bb)
{
rtx insn;
for (insn = bb->head; insn != NEXT_INSN (bb->end);
insn = NEXT_INSN (insn))
if (active_insn_p (insn))
{
sum += bb->frequency;
if (sum > limit)
return true;
}
}
return false;
}
static void
estimate_bb_frequencies (loops)
struct loops *loops;
{
basic_block bb;
REAL_VALUE_TYPE freq_max;
enum machine_mode double_mode = TYPE_MODE (double_type_node);
if (flag_branch_probabilities)
counts_to_freqs ();
else
{
REAL_VALUE_FROM_INT (real_zero, 0, 0, double_mode);
REAL_VALUE_FROM_INT (real_one, 1, 0, double_mode);
REAL_VALUE_FROM_INT (real_br_prob_base, REG_BR_PROB_BASE, 0, double_mode);
REAL_VALUE_FROM_INT (real_bb_freq_max, BB_FREQ_MAX, 0, double_mode);
REAL_VALUE_FROM_INT (real_one_half, 2, 0, double_mode);
REAL_ARITHMETIC (real_one_half, RDIV_EXPR, real_one, real_one_half);
REAL_ARITHMETIC (real_inv_br_prob_base, RDIV_EXPR, real_one, real_br_prob_base);
REAL_ARITHMETIC (real_almost_one, MINUS_EXPR, real_one, real_inv_br_prob_base);
mark_dfs_back_edges ();
FOR_EACH_BB (bb)
{
rtx last_insn = bb->end;
if (!can_predict_insn_p (last_insn))
{
int nedges = 0;
edge e;
for (e = bb->succ; e; e = e->succ_next)
{
nedges++;
if (e->probability != 0)
break;
}
if (!e)
for (e = bb->succ; e; e = e->succ_next)
e->probability = (REG_BR_PROB_BASE + nedges / 2) / nedges;
}
}
ENTRY_BLOCK_PTR->succ->probability = REG_BR_PROB_BASE;
alloc_aux_for_blocks (sizeof (struct block_info_def));
alloc_aux_for_edges (sizeof (struct edge_info_def));
FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, NULL, next_bb)
{
edge e;
BLOCK_INFO (bb)->tovisit = 0;
for (e = bb->succ; e; e = e->succ_next)
{
REAL_VALUE_FROM_INT (EDGE_INFO (e)->back_edge_prob,
e->probability, 0, double_mode);
REAL_ARITHMETIC (EDGE_INFO (e)->back_edge_prob,
MULT_EXPR, EDGE_INFO (e)->back_edge_prob,
real_inv_br_prob_base);
}
}
estimate_loops_at_level (loops->tree_root);
memcpy (&freq_max, &real_zero, sizeof (real_zero));
FOR_EACH_BB (bb)
if (REAL_VALUES_LESS
(freq_max, BLOCK_INFO (bb)->frequency))
memcpy (&freq_max, &BLOCK_INFO (bb)->frequency,
sizeof (freq_max));
REAL_ARITHMETIC (freq_max, RDIV_EXPR, real_bb_freq_max, freq_max);
FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, NULL, next_bb)
{
REAL_VALUE_TYPE tmp;
REAL_ARITHMETIC (tmp, MULT_EXPR, BLOCK_INFO (bb)->frequency,
freq_max);
REAL_ARITHMETIC (tmp, PLUS_EXPR, tmp, real_one_half);
bb->frequency = REAL_VALUE_UNSIGNED_FIX (tmp);
}
free_aux_for_blocks ();
free_aux_for_edges ();
}
compute_function_frequency ();
if (flag_reorder_functions)
choose_function_section ();
}
static void
compute_function_frequency ()
{
basic_block bb;
if (!profile_info.count_profiles_merged
|| !flag_branch_probabilities)
return;
cfun->function_frequency = FUNCTION_FREQUENCY_UNLIKELY_EXECUTED;
FOR_EACH_BB (bb)
{
if (maybe_hot_bb_p (bb))
{
cfun->function_frequency = FUNCTION_FREQUENCY_HOT;
return;
}
if (!probably_never_executed_bb_p (bb))
cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
}
}
static void
choose_function_section ()
{
if (DECL_SECTION_NAME (current_function_decl)
|| !targetm.have_named_sections
|| DECL_ONE_ONLY (current_function_decl))
return;
if (cfun->function_frequency == FUNCTION_FREQUENCY_HOT)
DECL_SECTION_NAME (current_function_decl) =
build_string (strlen (HOT_TEXT_SECTION_NAME), HOT_TEXT_SECTION_NAME);
if (cfun->function_frequency == FUNCTION_FREQUENCY_UNLIKELY_EXECUTED)
DECL_SECTION_NAME (current_function_decl) =
build_string (strlen (UNLIKELY_EXECUTED_TEXT_SECTION_NAME),
UNLIKELY_EXECUTED_TEXT_SECTION_NAME);
}