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Commit bfdade77 by Richard Kenner Committed by Richard Kenner
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* predict.c: Reformatting and minor cleanups. 

From-SVN: r48269
parent 6c7d86ec
Showing with 171 additions and 161 deletions
gcc/ChangeLog
Sat Dec 22 08:59:50 2001 Richard Kenner <kenner@vlsi1.ultra.nyu.edu>
* predict.c: Reformatting and minor cleanups.
* expr.c (expand_expr, case ADDR_EXPR): Handling taking address of
SAVE_EXPR.
* function.c (gen_mem_addressof): Add missing tests for SAVE_EXPR.
......
gcc/predict.c
/* Branch prediction routines for the GNU compiler.
Copyright (C) 2000, 2001 Free Software Foundation, Inc.
This file is part of GCC.
This file is part of GCC.
GCC 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, or (at your option)
any later version.
GCC 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, or (at your option) any later
version.
GCC 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.
GCC 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 GCC; see the file COPYING. If not, write to the Free
Software Foundation, 59 Temple Place - Suite 330, Boston, MA
02111-1307, USA. */
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING. If not, write to the Free
Software Foundation, 59 Temple Place - Suite 330, Boston, MA
02111-1307, USA. */
/* References:
......@@ -25,9 +25,7 @@
[2] "Static Branch Frequency and Program Profile Analysis"
Wu and Larus; MICRO-27.
[3] "Corpus-based Static Branch Prediction"
Calder, Grunwald, Lindsay, Martin, Mozer, and Zorn; PLDI '95.
*/
Calder, Grunwald, Lindsay, Martin, Mozer, and Zorn; PLDI '95. */
#include "config.h"
......@@ -67,6 +65,7 @@ static void counts_to_freqs PARAMS ((void));
/* Information we hold about each branch predictor.
Filled using information from predict.def. */
struct predictor_info
{
const char *const name; /* Name used in the debugging dumps. */
......@@ -81,10 +80,10 @@ struct predictor_info
/* Recompute hitrate in percent to our representation. */
#define HITRATE(VAL) ((int)((VAL) * REG_BR_PROB_BASE + 50) / 100)
#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[] = {
static const struct predictor_info predictor_info[]= {
#include "predict.def"
/* Upper bound on predictors. */
......@@ -100,6 +99,7 @@ predict_insn (insn, predictor, probability)
{
if (!any_condjump_p (insn))
abort ();
REG_NOTES (insn)
= gen_rtx_EXPR_LIST (REG_BR_PRED,
gen_rtx_CONCAT (VOIDmode,
......@@ -109,6 +109,7 @@ predict_insn (insn, predictor, probability)
}
/* Predict insn by given predictor. */
void
predict_insn_def (insn, predictor, taken)
rtx insn;
......@@ -116,12 +117,15 @@ predict_insn_def (insn, predictor, taken)
enum prediction taken;
{
int probability = predictor_info[(int) predictor].hitrate;
if (taken != TAKEN)
probability = REG_BR_PROB_BASE - probability;
predict_insn (insn, predictor, probability);
}
/* Predict edge E with given probability if possible. */
void
predict_edge (e, predictor, probability)
edge e;
......@@ -144,6 +148,7 @@ predict_edge (e, predictor, probability)
}
/* Predict edge E by given predictor if possible. */
void
predict_edge_def (e, predictor, taken)
edge e;
......@@ -154,29 +159,29 @@ predict_edge_def (e, predictor, taken)
if (taken != TAKEN)
probability = REG_BR_PROB_BASE - probability;
predict_edge (e, predictor, probability);
}
/* Invert all branch predictions or probability notes in the INSN. This needs
to be done each time we invert the condition used by the jump. */
void
invert_br_probabilities (insn)
rtx insn;
{
rtx note = REG_NOTES (insn);
while (note)
{
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)));
note = XEXP (note, 1);
}
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)));
}
/* Dump information about the branch prediction to the output file. */
static void
dump_prediction (predictor, probability, bb, used)
enum br_predictor predictor;
......@@ -194,25 +199,23 @@ dump_prediction (predictor, probability, bb, used)
fprintf (rtl_dump_file, " %s heuristics%s: %.1f%%",
predictor_info[predictor].name,
used ? "" : " (ignored)",
probability * 100.0 / REG_BR_PROB_BASE);
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,
(HOST_WIDEST_INT) bb->count);
fprintf (rtl_dump_file, HOST_WIDEST_INT_PRINT_DEC, bb->count);
fprintf (rtl_dump_file, " hit ");
fprintf (rtl_dump_file, HOST_WIDEST_INT_PRINT_DEC,
(HOST_WIDEST_INT) e->count);
fprintf (rtl_dump_file, " (%.1f%%)",
e->count * 100.0 / bb->count);
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");
}
/* Combine all REG_BR_PRED notes into single probability and attach REG_BR_PROB
note if not already present. Remove now useless REG_BR_PRED notes. */
static void
combine_predictions_for_insn (insn, bb)
rtx insn;
......@@ -220,7 +223,7 @@ combine_predictions_for_insn (insn, bb)
{
rtx prob_note = find_reg_note (insn, REG_BR_PROB, 0);
rtx *pnote = &REG_NOTES (insn);
rtx note = REG_NOTES (insn);
rtx note;
int best_probability = PROB_EVEN;
int best_predictor = END_PREDICTORS;
int combined_probability = REG_BR_PROB_BASE / 2;
......@@ -235,29 +238,27 @@ combine_predictions_for_insn (insn, bb)
/* We implement "first match" heuristics and use probability guessed
by predictor with smallest index. In the future we will use better
probability combination techniques. */
while (note)
{
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));
/* An FP math to avoid overflows of 32bit integers. */
combined_probability = (((double)combined_probability) * probability
* REG_BR_PROB_BASE / d + 0.5);
}
note = XEXP (note, 1);
}
/* Decide heuristic to use. In case we didn't match anything, use
no_prediction heuristic, in case we did match, use either
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));
/* Use FP math to avoid overflows of 32bit integers. */
combined_probability = (((double) combined_probability) * probability
* REG_BR_PROB_BASE / d + 0.5);
}
/* Decide which heuristic to use. In case we didn't match anything,
use no_prediction heuristic, in case we did match, use either
first match or Dempster-Shaffer theory depending on the flags. */
if (predictor_info [best_predictor].flags & PRED_FLAG_FIRST_MATCH)
......@@ -267,8 +268,7 @@ combine_predictions_for_insn (insn, bb)
dump_prediction (PRED_NO_PREDICTION, combined_probability, bb, true);
else
{
dump_prediction (PRED_DS_THEORY, combined_probability, bb,
!first_match);
dump_prediction (PRED_DS_THEORY, combined_probability, bb, !first_match);
dump_prediction (PRED_FIRST_MATCH, best_probability, bb, first_match);
}
......@@ -290,17 +290,20 @@ combine_predictions_for_insn (insn, bb)
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));
/* Save the prediction into CFG in case we are seeing non-degenerated
conditional jump. */
if (bb->succ->succ_next)
{
BRANCH_EDGE (bb)->probability = combined_probability;
FALLTHRU_EDGE (bb)->probability = REG_BR_PROB_BASE - combined_probability;
FALLTHRU_EDGE (bb)->probability
= REG_BR_PROB_BASE - combined_probability;
}
}
}
......@@ -335,37 +338,34 @@ estimate_probability (loops_info)
flow_loop_scan (loops_info, loop, LOOP_EXIT_EDGES);
exits = loop->num_exits;
for (j = loop->first->index;
j <= loop->last->index;
++j)
{
if (TEST_BIT (loop->nodes, j))
{
int header_found = 0;
edge e;
/* Loop branch heuristics - predict as taken an edge back to
a loop's head. */
for (j = loop->first->index; j <= loop->last->index; ++j)
if (TEST_BIT (loop->nodes, j))
{
int header_found = 0;
edge e;
/* Loop branch heuristics - predict an edge back to a
loop's head as taken. */
for (e = BASIC_BLOCK(j)->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);
}
/* Loop exit heuristics - predict an edge exiting the loop if the
conditinal has no loop header successors as not taken. */
if (!header_found)
for (e = BASIC_BLOCK(j)->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);
}
/* Loop exit heuristics - predict as not taken an edge
exiting the loop if the conditinal has no loop header
successors. */
if (!header_found)
for (e = BASIC_BLOCK(j)->succ; e; e = e->succ_next)
if (e->dest->index < 0
|| !TEST_BIT (loop->nodes, e->dest->index))
predict_edge (e, PRED_LOOP_EXIT,
(REG_BR_PROB_BASE
- predictor_info [(int)PRED_LOOP_EXIT].hitrate)
/ exits);
}
}
if (e->dest->index < 0
|| !TEST_BIT (loop->nodes, e->dest->index))
predict_edge
(e, PRED_LOOP_EXIT,
(REG_BR_PROB_BASE
- predictor_info [(int)PRED_LOOP_EXIT].hitrate)
/ exits);
}
}
/* Attempt to predict conditional jumps using a number of heuristics. */
......@@ -376,30 +376,27 @@ estimate_probability (loops_info)
rtx cond, earliest;
edge e;
/* If block has no successor, predict all possible paths to
it as improbable, as the block contains a call to a noreturn
function and thus can be executed only once. */
/* If block has no successor, predict all possible paths to it as
improbable, as the block contains a call to a noreturn function and
thus can be executed only once. */
if (bb->succ == NULL && !found_noreturn)
{
int y;
/* ??? Postdominator claims each noreturn block to be postdominated
by each, so we need to run only once. This needs to be changed
once postdominace algorithm is updated to say something more sane.
*/
once postdominace algorithm is updated to say something more
sane. */
found_noreturn = 1;
for (y = 0; y < n_basic_blocks; y++)
if (!TEST_BIT (post_dominators[y], i))
{
for (e = BASIC_BLOCK (y)->succ; e; e = e->succ_next)
for (e = BASIC_BLOCK (y)->succ; e; e = e->succ_next)
if (e->dest->index >= 0
&& TEST_BIT (post_dominators[e->dest->index], i))
predict_edge_def (e, PRED_NORETURN, NOT_TAKEN);
}
}
if (GET_CODE (last_insn) != JUMP_INSN
|| ! any_condjump_p (last_insn))
if (GET_CODE (last_insn) != JUMP_INSN || ! any_condjump_p (last_insn))
continue;
for (e = bb->succ; e; e = e->succ_next)
......@@ -413,12 +410,12 @@ estimate_probability (loops_info)
/* Look for block we are guarding (ie we dominate it,
but it doesn't postdominate us). */
if (e->dest != EXIT_BLOCK_PTR
&& e->dest != bb
if (e->dest != EXIT_BLOCK_PTR && e->dest != bb
&& TEST_BIT (dominators[e->dest->index], e->src->index)
&& !TEST_BIT (post_dominators[e->src->index], e->dest->index))
{
rtx insn;
/* The call heuristic claims that a guarded function call
is improbable. This is because such calls are often used
to signal exceptional situations such as printing error
......@@ -446,18 +443,14 @@ estimate_probability (loops_info)
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)))))
switch (GET_CODE (cond))
{
case EQ:
{
if (GET_CODE (cond) == EQ)
predict_insn_def (last_insn, PRED_POINTER, NOT_TAKEN);
break;
case NE:
else if (GET_CODE (cond) == NE)
predict_insn_def (last_insn, PRED_POINTER, TAKEN);
break;
default:
break;
}
}
else
/* Try "opcode heuristic."
EQ tests are usually false and NE tests are usually true. Also,
most quantities are positive, so we can make the appropriate guesses
......@@ -479,11 +472,13 @@ estimate_probability (loops_info)
;
/* Comparisons with 0 are often used for booleans and there is
nothing usefull to predict about them. */
else if (XEXP (cond, 1) == const0_rtx || XEXP (cond, 0) == const0_rtx)
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:
/* Floating point comparisons appears to behave in a very
......@@ -493,23 +488,28 @@ estimate_probability (loops_info)
;
/* Comparisons with 0 are often used for booleans and there is
nothing usefull to predict about them. */
else if (XEXP (cond, 1) == const0_rtx || XEXP (cond, 0) == const0_rtx)
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
......@@ -524,23 +524,19 @@ estimate_probability (loops_info)
/* Attach the combined probability to each conditional jump. */
for (i = 0; i < n_basic_blocks; i++)
{
rtx last_insn = BLOCK_END (i);
if (GET_CODE (BLOCK_END (i)) == JUMP_INSN
&& any_condjump_p (BLOCK_END (i)))
combine_predictions_for_insn (BLOCK_END (i), BASIC_BLOCK (i));
if (GET_CODE (last_insn) != JUMP_INSN
|| ! any_condjump_p (last_insn))
continue;
combine_predictions_for_insn (last_insn, BASIC_BLOCK (i));
}
sbitmap_vector_free (post_dominators);
sbitmap_vector_free (dominators);
estimate_bb_frequencies (loops_info);
}
/* __builtin_expect dropped tokens into the insn stream describing
expected values of registers. Generate branch probabilities
based off these values. */
/* __builtin_expect dropped tokens into the insn stream describing expected
values of registers. Generate branch probabilities based off these
values. */
void
expected_value_to_br_prob ()
......@@ -566,20 +562,19 @@ expected_value_to_br_prob ()
ev = NULL_RTX;
continue;
default:
/* Look for insns that clobber the EV register. */
if (ev && reg_set_p (ev_reg, insn))
ev = NULL_RTX;
continue;
case JUMP_INSN:
/* Look for simple conditional branches. If we haven't got an
expected value yet, no point going further. */
if (GET_CODE (insn) != JUMP_INSN || ev == NULL_RTX)
continue;
if (! any_condjump_p (insn))
if (GET_CODE (insn) != JUMP_INSN || ev == NULL_RTX
|| ! any_condjump_p (insn))
continue;
break;
default:
/* Look for insns that clobber the EV register. */
if (ev && reg_set_p (ev_reg, insn))
ev = NULL_RTX;
continue;
}
/* Collect the branch condition, hopefully relative to EV_REG. */
......@@ -593,8 +588,7 @@ expected_value_to_br_prob ()
Could use cselib to try and reduce this further. */
cond = XEXP (SET_SRC (pc_set (insn)), 0);
cond = canonicalize_condition (insn, cond, 0, NULL, ev_reg);
if (! cond
|| XEXP (cond, 0) != ev_reg
if (! cond || XEXP (cond, 0) != ev_reg
|| GET_CODE (XEXP (cond, 1)) != CONST_INT)
continue;
......@@ -650,6 +644,7 @@ typedef struct edge_info_def
/* Helper function for estimate_bb_frequencies.
Propagate the frequencies for loops headed by HEAD. */
static void
propagate_freq (head)
basic_block head;
......@@ -668,6 +663,7 @@ propagate_freq (head)
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++;
......@@ -683,7 +679,7 @@ propagate_freq (head)
BLOCK_INFO (head)->frequency = 1;
for (; bb; bb = nextbb)
{
volatile double cyclic_probability = 0, frequency = 0;
double cyclic_probability = 0, frequency = 0;
nextbb = BLOCK_INFO (bb)->next;
BLOCK_INFO (bb)->next = NULL;
......@@ -716,9 +712,9 @@ propagate_freq (head)
/* Compute back edge frequencies. */
for (e = bb->succ; e; e = e->succ_next)
if (e->dest == head)
EDGE_INFO (e)->back_edge_prob = (e->probability
* BLOCK_INFO (bb)->frequency
/ REG_BR_PROB_BASE);
EDGE_INFO (e)->back_edge_prob
= ((e->probability * BLOCK_INFO (bb)->frequency)
/ REG_BR_PROB_BASE);
/* Propagate to successor blocks. */
for (e = bb->succ; e; e = e->succ_next)
......@@ -732,6 +728,7 @@ propagate_freq (head)
nextbb = e->dest;
else
BLOCK_INFO (last)->next = e->dest;
last = e->dest;
}
}
......@@ -739,6 +736,7 @@ propagate_freq (head)
}
/* Estimate probabilities of loopback edges in loops at same nest level. */
static void
estimate_loops_at_level (first_loop)
struct loop *first_loop;
......@@ -753,7 +751,8 @@ estimate_loops_at_level (first_loop)
estimate_loops_at_level (loop->inner);
/* Find current loop back edge and mark it. */
for (e = loop->latch->succ; e->dest != loop->header; e = e->succ_next);
for (e = loop->latch->succ; e->dest != loop->header; e = e->succ_next)
;
EDGE_INFO (e)->back_edge = 1;
......@@ -764,6 +763,7 @@ estimate_loops_at_level (first_loop)
for (l = loop->next; l; l = l->next)
if (l->header == loop->header)
break;
if (l)
continue;
}
......@@ -774,11 +774,13 @@ estimate_loops_at_level (first_loop)
EXECUTE_IF_SET_IN_SBITMAP (l->nodes, 0, n,
BLOCK_INFO (BASIC_BLOCK (n))->tovisit = 1
);
propagate_freq (loop->header);
}
}
/* Convert counts measured by profile driven feedback to frequencies. */
static void
counts_to_freqs ()
{
......@@ -786,28 +788,28 @@ counts_to_freqs ()
int i;
for (i = 0; i < n_basic_blocks; i++)
if (BASIC_BLOCK (i)->count > count_max)
count_max = BASIC_BLOCK (i)->count;
count_max = MAX (BASIC_BLOCK (i)->count, count_max);
for (i = -2; i < n_basic_blocks; i++)
{
basic_block bb;
if (i == -2)
bb = ENTRY_BLOCK_PTR;
else if (i == -1)
bb = EXIT_BLOCK_PTR;
else
bb = BASIC_BLOCK (i);
bb->frequency = ((bb->count * BB_FREQ_MAX + count_max / 2)
/ count_max);
bb->frequency = (bb->count * BB_FREQ_MAX + count_max / 2) / count_max;
}
}
/* Return true if function is likely to be expensive, so there is no point
to optimizer performance of prologue, epilogue or do inlining at the
expense of code size growth. THRESHOLD is the limit of number
of isntructions function can execute at average to be still considered
not expensive. */
/* Return true if function is likely to be expensive, so there is no point to
optimize performance of prologue, epilogue or do inlining at the expense
of code size growth. THRESHOLD is the limit of number of isntructions
function can execute at average to be still considered not expensive. */
bool
expensive_function_p (threshold)
int threshold;
......@@ -836,19 +838,19 @@ expensive_function_p (threshold)
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;
}
if (active_insn_p (insn))
{
sum += bb->frequency;
if (sum > limit)
return true;
}
}
return false;
}
/* Estimate basic blocks frequency by given branch probabilities. */
static void
estimate_bb_frequencies (loops)
struct loops *loops;
......@@ -906,6 +908,7 @@ estimate_bb_frequencies (loops)
fallthru->probability = REG_BR_PROB_BASE - probability;
}
}
ENTRY_BLOCK_PTR->succ->probability = REG_BR_PROB_BASE;
/* Set up block info for each basic block. */
......@@ -922,11 +925,13 @@ estimate_bb_frequencies (loops)
bb = EXIT_BLOCK_PTR;
else
bb = BASIC_BLOCK (i);
BLOCK_INFO (bb)->tovisit = 0;
for (e = bb->succ; e; e = e->succ_next)
EDGE_INFO (e)->back_edge_prob = ((double) e->probability
/ REG_BR_PROB_BASE);
}
/* First compute probabilities locally for each loop from innermost
to outermost to examine probabilities for back edges. */
estimate_loops_at_level (loops->tree_root);
......@@ -934,6 +939,7 @@ estimate_bb_frequencies (loops)
/* Now fake loop around whole function to finalize probabilities. */
for (i = 0; i < n_basic_blocks; i++)
BLOCK_INFO (BASIC_BLOCK (i))->tovisit = 1;
BLOCK_INFO (ENTRY_BLOCK_PTR)->tovisit = 1;
BLOCK_INFO (EXIT_BLOCK_PTR)->tovisit = 1;
propagate_freq (ENTRY_BLOCK_PTR);
......@@ -941,17 +947,19 @@ estimate_bb_frequencies (loops)
for (i = 0; i < n_basic_blocks; i++)
if (BLOCK_INFO (BASIC_BLOCK (i))->frequency > freq_max)
freq_max = BLOCK_INFO (BASIC_BLOCK (i))->frequency;
for (i = -2; i < n_basic_blocks; i++)
{
basic_block bb;
if (i == -2)
bb = ENTRY_BLOCK_PTR;
else if (i == -1)
bb = EXIT_BLOCK_PTR;
else
bb = BASIC_BLOCK (i);
bb->frequency = (BLOCK_INFO (bb)->frequency * BB_FREQ_MAX / freq_max
+ 0.5);
bb->frequency
= BLOCK_INFO (bb)->frequency * BB_FREQ_MAX / freq_max + 0.5;
}
free_aux_for_blocks ();
......
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