/* Branch prediction routines for the GNU compiler.
- Copyright (C) 2000, 2001, 2002 Free Software Foundation, Inc.
+ Copyright (C) 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
This file is part of GCC.
#include "config.h"
#include "system.h"
+#include "coretypes.h"
+#include "tm.h"
#include "tree.h"
#include "rtl.h"
#include "tm_p.h"
#include "recog.h"
#include "expr.h"
#include "predict.h"
-#include "profile.h"
-#include "real.h"
+#include "coverage.h"
+#include "sreal.h"
#include "params.h"
#include "target.h"
#include "loop.h"
+#include "cfgloop.h"
-/* real constants: 0, 1, 1-1/REG_BR_PROB_BASE, REG_BR_PROB_BASE, 0.5,
- REAL_BB_FREQ_MAX. */
-static REAL_VALUE_TYPE real_zero, real_one, real_almost_one, real_br_prob_base,
- real_one_half, real_bb_freq_max;
+/* real constants: 0, 1, 1-1/REG_BR_PROB_BASE, REG_BR_PROB_BASE,
+ 1/REG_BR_PROB_BASE, 0.5, BB_FREQ_MAX. */
+static sreal real_zero, real_one, real_almost_one, real_br_prob_base,
+ real_inv_br_prob_base, real_one_half, real_bb_freq_max;
/* Random guesstimation given names. */
-#define PROB_NEVER (0)
#define PROB_VERY_UNLIKELY (REG_BR_PROB_BASE / 10 - 1)
-#define PROB_UNLIKELY (REG_BR_PROB_BASE * 4 / 10 - 1)
#define PROB_EVEN (REG_BR_PROB_BASE / 2)
-#define PROB_LIKELY (REG_BR_PROB_BASE - PROB_UNLIKELY)
#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 predicted_by_p (basic_block, enum br_predictor);
+static void combine_predictions_for_insn (rtx, basic_block);
+static void dump_prediction (enum br_predictor, int, basic_block, int);
+static void estimate_loops_at_level (struct loop *loop);
+static void propagate_freq (struct loop *);
+static void estimate_bb_frequencies (struct loops *);
+static int counts_to_freqs (void);
+static void process_note_predictions (basic_block, int *);
+static void process_note_prediction (basic_block, int *, int, int);
+static bool last_basic_block_p (basic_block);
+static void compute_function_frequency (void);
+static void choose_function_section (void);
+static bool can_predict_insn_p (rtx);
/* Information we hold about each branch predictor.
Filled using information from predict.def. */
#undef DEF_PREDICTOR
/* Return true in case BB can be CPU intensive and should be optimized
- for maximal perofmrance. */
+ for maximal performance. */
bool
-maybe_hot_bb_p (bb)
- basic_block bb;
+maybe_hot_bb_p (basic_block bb)
{
- if (profile_info.count_profiles_merged
- && flag_branch_probabilities
+ if (profile_info && flag_branch_probabilities
&& (bb->count
- < profile_info.max_counter_in_program
- / PARAM_VALUE (HOT_BB_COUNT_FRACTION)))
+ < profile_info->sum_max / PARAM_VALUE (HOT_BB_COUNT_FRACTION)))
return false;
if (bb->frequency < BB_FREQ_MAX / PARAM_VALUE (HOT_BB_FREQUENCY_FRACTION))
return false;
/* Return true in case BB is cold and should be optimized for size. */
bool
-probably_cold_bb_p (bb)
- basic_block bb;
+probably_cold_bb_p (basic_block bb)
{
- if (profile_info.count_profiles_merged
- && flag_branch_probabilities
+ if (profile_info && flag_branch_probabilities
&& (bb->count
- < profile_info.max_counter_in_program
- / PARAM_VALUE (HOT_BB_COUNT_FRACTION)))
+ < profile_info->sum_max / PARAM_VALUE (HOT_BB_COUNT_FRACTION)))
return true;
if (bb->frequency < BB_FREQ_MAX / PARAM_VALUE (HOT_BB_FREQUENCY_FRACTION))
return true;
/* Return true in case BB is probably never executed. */
bool
-probably_never_executed_bb_p (bb)
- basic_block bb;
+probably_never_executed_bb_p (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;
+ if (profile_info && flag_branch_probabilities)
+ return ((bb->count + profile_info->runs / 2) / profile_info->runs) == 0;
return false;
}
PREDICTOR. */
static bool
-predicted_by_p (bb, predictor)
- basic_block bb;
- enum br_predictor predictor;
+predicted_by_p (basic_block bb, enum br_predictor predictor)
{
rtx note;
- if (!INSN_P (bb->end))
+ if (!INSN_P (BB_END (bb)))
return false;
- for (note = REG_NOTES (bb->end); note; note = XEXP (note, 1))
+ for (note = REG_NOTES (BB_END (bb)); note; note = XEXP (note, 1))
if (REG_NOTE_KIND (note) == REG_BR_PRED
&& INTVAL (XEXP (XEXP (note, 0), 0)) == (int)predictor)
return true;
}
void
-predict_insn (insn, predictor, probability)
- rtx insn;
- int probability;
- enum br_predictor predictor;
+predict_insn (rtx insn, enum br_predictor predictor, int probability)
{
if (!any_condjump_p (insn))
abort ();
+ if (!flag_guess_branch_prob)
+ return;
REG_NOTES (insn)
= gen_rtx_EXPR_LIST (REG_BR_PRED,
/* Predict insn by given predictor. */
void
-predict_insn_def (insn, predictor, taken)
- rtx insn;
- enum br_predictor predictor;
- enum prediction taken;
+predict_insn_def (rtx insn, enum br_predictor predictor,
+ enum prediction taken)
{
int probability = predictor_info[(int) predictor].hitrate;
/* Predict edge E with given probability if possible. */
void
-predict_edge (e, predictor, probability)
- edge e;
- int probability;
- enum br_predictor predictor;
+predict_edge (edge e, enum br_predictor predictor, int probability)
{
rtx last_insn;
- last_insn = e->src->end;
+ last_insn = BB_END (e->src);
/* We can store the branch prediction information only about
conditional jumps. */
predict_insn (last_insn, predictor, probability);
}
+/* Return true when we can store prediction on insn INSN.
+ At the moment we represent predictions only on conditional
+ jumps, not at computed jump or other complicated cases. */
+static bool
+can_predict_insn_p (rtx insn)
+{
+ return (GET_CODE (insn) == JUMP_INSN
+ && any_condjump_p (insn)
+ && BLOCK_FOR_INSN (insn)->succ->succ_next);
+}
+
/* Predict edge E by given predictor if possible. */
void
-predict_edge_def (e, predictor, taken)
- edge e;
- enum br_predictor predictor;
- enum prediction taken;
+predict_edge_def (edge e, enum br_predictor predictor,
+ enum prediction taken)
{
int probability = predictor_info[(int) predictor].hitrate;
to be done each time we invert the condition used by the jump. */
void
-invert_br_probabilities (insn)
- rtx insn;
+invert_br_probabilities (rtx insn)
{
rtx note;
/* Dump information about the branch prediction to the output file. */
static void
-dump_prediction (predictor, probability, bb, used)
- enum br_predictor predictor;
- int probability;
- basic_block bb;
- int used;
+dump_prediction (enum br_predictor predictor, int probability,
+ basic_block bb, int used)
{
edge e = bb->succ;
- if (!rtl_dump_file)
+ if (!dump_file)
return;
while (e && (e->flags & EDGE_FALLTHRU))
e = e->succ_next;
- fprintf (rtl_dump_file, " %s heuristics%s: %.1f%%",
+ fprintf (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);
+ fprintf (dump_file, " exec ");
+ fprintf (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 (dump_file, " hit ");
+ fprintf (dump_file, HOST_WIDEST_INT_PRINT_DEC, e->count);
+ fprintf (dump_file, " (%.1f%%)", e->count * 100.0 / bb->count);
}
}
- fprintf (rtl_dump_file, "\n");
+ fprintf (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;
- basic_block bb;
+combine_predictions_for_insn (rtx insn, basic_block bb)
{
rtx prob_note = find_reg_note (insn, REG_BR_PROB, 0);
rtx *pnote = ®_NOTES (insn);
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),
+ if (dump_file)
+ fprintf (dump_file, "Predictions for insn %i bb %i\n", INSN_UID (insn),
bb->index);
/* We implement "first match" heuristics and use probability guessed
predictions). */
void
-estimate_probability (loops_info)
- struct loops *loops_info;
+estimate_probability (struct loops *loops_info)
{
- dominance_info dominators, post_dominators;
basic_block bb;
- int i;
+ unsigned i;
connect_infinite_loops_to_exit ();
- dominators = calculate_dominance_info (CDI_DOMINATORS);
- post_dominators = calculate_dominance_info (CDI_POST_DOMINATORS);
+ calculate_dominance_info (CDI_DOMINATORS);
+ calculate_dominance_info (CDI_POST_DOMINATORS);
/* Try to predict out blocks in a loop that are not part of a
natural loop. */
for (i = 1; i < loops_info->num; i++)
{
basic_block bb, *bbs;
- int j;
+ unsigned j;
int exits;
struct loop *loop = loops_info->parray[i];
+ struct niter_desc desc;
+ unsigned HOST_WIDE_INT niter;
- flow_loop_scan (loops_info, loop, LOOP_EXIT_EDGES);
+ flow_loop_scan (loop, LOOP_EXIT_EDGES);
exits = loop->num_exits;
+ iv_analysis_loop_init (loop);
+ find_simple_exit (loop, &desc);
+
+ if (desc.simple_p && desc.const_iter)
+ {
+ int prob;
+ niter = desc.niter + 1;
+ if (niter == 0) /* We might overflow here. */
+ niter = desc.niter;
+
+ prob = (REG_BR_PROB_BASE
+ - (REG_BR_PROB_BASE + niter /2) / niter);
+ /* Branch prediction algorithm gives 0 frequency for everything
+ after the end of loop for loop having 0 probability to finish. */
+ if (prob == REG_BR_PROB_BASE)
+ prob = REG_BR_PROB_BASE - 1;
+ predict_edge (desc.in_edge, PRED_LOOP_ITERATIONS,
+ prob);
+ }
+
bbs = get_loop_body (loop);
for (j = 0; j < loop->num_nodes; j++)
{
statements construct loops via "non-loop" constructs
in the source language and are better to be handled
separately. */
- if (predicted_by_p (bb, PRED_CONTINUE))
+ if (!can_predict_insn_p (BB_END (bb))
+ || predicted_by_p (bb, PRED_CONTINUE))
continue;
/* Loop branch heuristics - predict an edge back to a
}
/* Loop exit heuristics - predict an edge exiting the loop if the
- conditinal has no loop header successors as not taken. */
+ conditional has no loop header successors as not taken. */
if (!header_found)
for (e = bb->succ; e; e = e->succ_next)
if (e->dest->index < 0
- predictor_info [(int) PRED_LOOP_EXIT].hitrate)
/ exits);
}
+
+ /* Free basic blocks from get_loop_body. */
+ free (bbs);
}
+ iv_analysis_done ();
+
/* Attempt to predict conditional jumps using a number of heuristics. */
FOR_EACH_BB (bb)
{
- rtx last_insn = bb->end;
+ rtx last_insn = BB_END (bb);
rtx cond, earliest;
edge e;
- if (GET_CODE (last_insn) != JUMP_INSN || ! any_condjump_p (last_insn))
+ if (! can_predict_insn_p (last_insn))
continue;
for (e = bb->succ; e; e = e->succ_next)
/* 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
- && dominated_by_p (dominators, e->dest, e->src)
- && !dominated_by_p (post_dominators, e->src, e->dest))
+ && dominated_by_p (CDI_DOMINATORS, e->dest, e->src)
+ && !dominated_by_p (CDI_POST_DOMINATORS, e->src, e->dest))
{
rtx insn;
is improbable. This is because such calls are often used
to signal exceptional situations such as printing error
messages. */
- for (insn = e->dest->head; insn != NEXT_INSN (e->dest->end);
+ for (insn = BB_HEAD (e->dest); insn != NEXT_INSN (BB_END (e->dest));
insn = NEXT_INSN (insn))
if (GET_CODE (insn) == CALL_INSN
/* Constant and pure calls are hardly used to signalize
}
}
- cond = get_condition (last_insn, &earliest);
+ cond = get_condition (last_insn, &earliest, false);
if (! cond)
continue;
/* Try "pointer heuristic."
A comparison ptr == 0 is predicted as false.
Similarly, a comparison ptr1 == ptr2 is predicted as false. */
- if (GET_RTX_CLASS (GET_CODE (cond)) == '<'
+ if (COMPARISON_P (cond)
&& ((REG_P (XEXP (cond, 0)) && REG_POINTER (XEXP (cond, 0)))
|| (REG_P (XEXP (cond, 1)) && REG_POINTER (XEXP (cond, 1)))))
{
case EQ:
case UNEQ:
/* Floating point comparisons appears to behave in a very
- inpredictable way because of special role of = tests in
+ unpredictable way because of special role of = tests in
FP code. */
if (FLOAT_MODE_P (GET_MODE (XEXP (cond, 0))))
;
/* Comparisons with 0 are often used for booleans and there is
- nothing usefull to predict about them. */
+ nothing useful to predict about them. */
else if (XEXP (cond, 1) == const0_rtx
|| XEXP (cond, 0) == const0_rtx)
;
case NE:
case LTGT:
/* Floating point comparisons appears to behave in a very
- inpredictable way because of special role of = tests in
+ unpredictable way because of special role of = tests in
FP code. */
if (FLOAT_MODE_P (GET_MODE (XEXP (cond, 0))))
;
/* Comparisons with 0 are often used for booleans and there is
- nothing usefull to predict about them. */
+ nothing useful to predict about them. */
else if (XEXP (cond, 1) == const0_rtx
|| XEXP (cond, 0) == const0_rtx)
;
/* Attach the combined probability to each conditional jump. */
FOR_EACH_BB (bb)
- if (GET_CODE (bb->end) == JUMP_INSN
- && any_condjump_p (bb->end)
+ if (GET_CODE (BB_END (bb)) == JUMP_INSN
+ && any_condjump_p (BB_END (bb))
&& bb->succ->succ_next != NULL)
- combine_predictions_for_insn (bb->end, bb);
+ combine_predictions_for_insn (BB_END (bb), bb);
- free_dominance_info (post_dominators);
- free_dominance_info (dominators);
+ free_dominance_info (CDI_POST_DOMINATORS);
remove_fake_edges ();
estimate_bb_frequencies (loops_info);
values. */
void
-expected_value_to_br_prob ()
+expected_value_to_br_prob (void)
{
rtx insn, cond, ev = NULL_RTX, ev_reg = NULL_RTX;
(lt r70, r71)
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);
+ cond = canonicalize_condition (insn, cond, 0, NULL, ev_reg, false);
if (! cond || XEXP (cond, 0) != ev_reg
|| GET_CODE (XEXP (cond, 1)) != CONST_INT)
continue;
}
}
\f
-/* Check whether this is the last basic block of function. Commonly tehre
- is one extra common cleanup block. */
+/* Check whether this is the last basic block of function. Commonly
+ there is one extra common cleanup block. */
static bool
-last_basic_block_p (bb)
- basic_block bb;
+last_basic_block_p (basic_block bb)
{
if (bb == EXIT_BLOCK_PTR)
return false;
&& bb->succ->dest->next_bb == EXIT_BLOCK_PTR));
}
-/* Sets branch probabilities according to PREDiction and FLAGS. HEADS[bb->index]
- should be index of basic block in that we need to alter branch predictions
- (i.e. the first of our dominators such that we do not post-dominate it)
- (but we fill this information on demand, so -1 may be there in case this
- was not needed yet). */
+/* Sets branch probabilities according to PREDiction and
+ FLAGS. HEADS[bb->index] should be index of basic block in that we
+ need to alter branch predictions (i.e. the first of our dominators
+ such that we do not post-dominate it) (but we fill this information
+ on demand, so -1 may be there in case this was not needed yet). */
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;
+process_note_prediction (basic_block bb, int *heads, int pred, int flags)
{
edge e;
int y;
find first dominator that we do not post-dominate (we are
using already known members of heads array). */
basic_block ai = bb;
- basic_block next_ai = get_immediate_dominator (dominators, bb);
+ basic_block next_ai = get_immediate_dominator (CDI_DOMINATORS, bb);
int head;
while (heads[next_ai->index] < 0)
{
- if (!dominated_by_p (post_dominators, next_ai, bb))
+ if (!dominated_by_p (CDI_POST_DOMINATORS, next_ai, bb))
break;
heads[next_ai->index] = ai->index;
ai = next_ai;
- next_ai = get_immediate_dominator (dominators, next_ai);
+ next_ai = get_immediate_dominator (CDI_DOMINATORS, next_ai);
}
- if (!dominated_by_p (post_dominators, next_ai, bb))
+ if (!dominated_by_p (CDI_POST_DOMINATORS, next_ai, bb))
head = next_ai->index;
else
head = heads[next_ai->index];
/* Now find the edge that leads to our branch and aply the prediction. */
- if (y == last_basic_block)
+ if (y == last_basic_block || !can_predict_insn_p (BB_END (BASIC_BLOCK (y))))
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))
+ && dominated_by_p (CDI_POST_DOMINATORS, e->dest, bb))
predict_edge_def (e, pred, taken);
}
process_note_prediction. */
static void
-process_note_predictions (bb, heads, dominators, post_dominators)
- basic_block bb;
- int *heads;
- dominance_info dominators;
- dominance_info post_dominators;
+process_note_predictions (basic_block bb, int *heads)
{
rtx insn;
edge e;
- /* Additionaly, we check here for blocks with no successors. */
+ /* Additionally, we check here for blocks with no successors. */
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))
+ for (insn = BB_END (bb); insn;
+ was_bb_head |= (insn == BB_HEAD (bb)), insn = PREV_INSN (insn))
{
if (GET_CODE (insn) != NOTE)
{
/* Process single prediction note. */
process_note_prediction (bb,
heads,
- dominators,
- post_dominators,
alg, (int) NOTE_PREDICTION_FLAGS (insn));
delete_insn (insn);
}
/* This block ended from other reasons than because of return.
If it is because of noreturn call, this should certainly not
be taken. Otherwise it is probably some error recovery. */
- process_note_prediction (bb,
- heads,
- dominators,
- post_dominators, PRED_NORETURN, NOT_TAKEN);
+ process_note_prediction (bb, heads, PRED_NORETURN, NOT_TAKEN);
}
}
branch probabilities. */
void
-note_prediction_to_br_prob ()
+note_prediction_to_br_prob (void)
{
basic_block bb;
- dominance_info post_dominators, dominators;
int *heads;
/* To enable handling of noreturn blocks. */
add_noreturn_fake_exit_edges ();
connect_infinite_loops_to_exit ();
- post_dominators = calculate_dominance_info (CDI_POST_DOMINATORS);
- dominators = calculate_dominance_info (CDI_DOMINATORS);
+ calculate_dominance_info (CDI_POST_DOMINATORS);
+ calculate_dominance_info (CDI_DOMINATORS);
heads = xmalloc (sizeof (int) * last_basic_block);
memset (heads, -1, sizeof (int) * last_basic_block);
/* Process all prediction notes. */
FOR_EACH_BB (bb)
- process_note_predictions (bb, heads, dominators, post_dominators);
+ process_note_predictions (bb, heads);
- free_dominance_info (post_dominators);
- free_dominance_info (dominators);
+ free_dominance_info (CDI_POST_DOMINATORS);
+ free_dominance_info (CDI_DOMINATORS);
free (heads);
remove_fake_edges ();
typedef struct block_info_def
{
/* Estimated frequency of execution of basic_block. */
- REAL_VALUE_TYPE frequency;
+ sreal frequency;
/* To keep queue of basic blocks to process. */
basic_block next;
- /* True if block needs to be visited in prop_freqency. */
- int tovisit:1;
+ /* True if block needs to be visited in propagate_freq. */
+ unsigned int tovisit:1;
/* Number of predecessors we need to visit first. */
int npredecessors;
/* In case edge is an loopback edge, the probability edge will be reached
in case header is. Estimated number of iterations of the loop can be
then computed as 1 / (1 - back_edge_prob). */
- REAL_VALUE_TYPE back_edge_prob;
+ sreal back_edge_prob;
/* True if the edge is an loopback edge in the natural loop. */
- int back_edge:1;
+ unsigned int back_edge:1;
} *edge_info;
#define BLOCK_INFO(B) ((block_info) (B)->aux)
Propagate the frequencies for LOOP. */
static void
-propagate_freq (loop)
- struct loop *loop;
+propagate_freq (struct loop *loop)
{
basic_block head = loop->header;
basic_block bb;
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,
+ && dump_file && !EDGE_INFO (e)->back_edge)
+ fprintf (dump_file,
"Irreducible region hit, ignoring edge to %i->%i\n",
e->src->index, bb->index);
BLOCK_INFO (bb)->npredecessors = count;
last = head;
for (bb = head; bb; bb = nextbb)
{
- REAL_VALUE_TYPE cyclic_probability, frequency;
+ sreal cyclic_probability, frequency;
memcpy (&cyclic_probability, &real_zero, sizeof (real_zero));
memcpy (&frequency, &real_zero, sizeof (real_zero));
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);
+ sreal_add (&cyclic_probability, &cyclic_probability,
+ &EDGE_INFO (e)->back_edge_prob);
}
else if (!(e->flags & EDGE_DFS_BACK))
{
- REAL_VALUE_TYPE tmp;
+ sreal tmp;
/* frequency += (e->probability
* BLOCK_INFO (e->src)->frequency /
REG_BR_PROB_BASE); */
- 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, RDIV_EXPR, tmp, real_br_prob_base);
- REAL_ARITHMETIC (frequency, PLUS_EXPR, frequency, tmp);
+ sreal_init (&tmp, e->probability, 0);
+ sreal_mul (&tmp, &tmp, &BLOCK_INFO (e->src)->frequency);
+ sreal_mul (&tmp, &tmp, &real_inv_br_prob_base);
+ sreal_add (&frequency, &frequency, &tmp);
}
- if (REAL_VALUES_LESS (real_almost_one, cyclic_probability))
- memcpy (&cyclic_probability, &real_almost_one, sizeof (real_zero));
+ if (sreal_compare (&cyclic_probability, &real_zero) == 0)
+ {
+ memcpy (&BLOCK_INFO (bb)->frequency, &frequency,
+ sizeof (frequency));
+ }
+ else
+ {
+ if (sreal_compare (&cyclic_probability, &real_almost_one) > 0)
+ {
+ memcpy (&cyclic_probability, &real_almost_one,
+ sizeof (real_almost_one));
+ }
- /* BLOCK_INFO (bb)->frequency = frequency / (1 - cyclic_probability)
- */
+ /* BLOCK_INFO (bb)->frequency = frequency
+ / (1 - cyclic_probability) */
- REAL_ARITHMETIC (cyclic_probability, MINUS_EXPR, real_one,
- cyclic_probability);
- REAL_ARITHMETIC (BLOCK_INFO (bb)->frequency,
- RDIV_EXPR, frequency, cyclic_probability);
+ sreal_sub (&cyclic_probability, &real_one, &cyclic_probability);
+ sreal_div (&BLOCK_INFO (bb)->frequency,
+ &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;
+ sreal tmp;
/* EDGE_INFO (e)->back_edge_prob
= ((e->probability * BLOCK_INFO (bb)->frequency)
/ REG_BR_PROB_BASE); */
- 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,
- RDIV_EXPR, tmp, real_br_prob_base);
+ sreal_init (&tmp, e->probability, 0);
+ sreal_mul (&tmp, &tmp, &BLOCK_INFO (bb)->frequency);
+ sreal_mul (&EDGE_INFO (e)->back_edge_prob,
+ &tmp, &real_inv_br_prob_base);
}
/* Propagate to successor blocks. */
/* Estimate probabilities of loopback edges in loops at same nest level. */
static void
-estimate_loops_at_level (first_loop)
- struct loop *first_loop;
+estimate_loops_at_level (struct loop *first_loop)
{
struct loop *loop;
{
edge e;
basic_block *bbs;
- int i;
+ unsigned i;
estimate_loops_at_level (loop->inner);
-
+
if (loop->latch->succ) /* Do not do this for dummy function loop. */
{
/* Find current loop back edge and mark it. */
}
}
-/* Convert counts measured by profile driven feedback to frequencies. */
+/* Convert counts measured by profile driven feedback to frequencies.
+ Return nonzero iff there was any nonzero execution count. */
-static void
-counts_to_freqs ()
+static int
+counts_to_freqs (void)
{
- HOST_WIDEST_INT count_max = 1;
+ gcov_type count_max, true_count_max = 0;
basic_block bb;
FOR_EACH_BB (bb)
- count_max = MAX (bb->count, count_max);
+ true_count_max = MAX (bb->count, true_count_max);
+ count_max = MAX (true_count_max, 1);
FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, NULL, next_bb)
bb->frequency = (bb->count * BB_FREQ_MAX + count_max / 2) / count_max;
+ return true_count_max;
}
/* 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
+ of code size growth. THRESHOLD is the limit of number of instructions
function can execute at average to be still considered not expensive. */
bool
-expensive_function_p (threshold)
- int threshold;
+expensive_function_p (int threshold)
{
unsigned int sum = 0;
basic_block bb;
{
rtx insn;
- for (insn = bb->head; insn != NEXT_INSN (bb->end);
+ for (insn = BB_HEAD (bb); insn != NEXT_INSN (BB_END (bb));
insn = NEXT_INSN (insn))
if (active_insn_p (insn))
{
/* Estimate basic blocks frequency by given branch probabilities. */
static void
-estimate_bb_frequencies (loops)
- struct loops *loops;
+estimate_bb_frequencies (struct loops *loops)
{
basic_block bb;
- REAL_VALUE_TYPE freq_max;
- enum machine_mode double_mode = TYPE_MODE (double_type_node);
+ sreal freq_max;
- if (flag_branch_probabilities)
- counts_to_freqs ();
- else
+ if (!flag_branch_probabilities || !counts_to_freqs ())
{
- 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_almost_one, RDIV_EXPR, real_one, real_br_prob_base);
- REAL_ARITHMETIC (real_almost_one, MINUS_EXPR, real_one, real_almost_one);
+ static int real_values_initialized = 0;
+
+ if (!real_values_initialized)
+ {
+ real_values_initialized = 1;
+ sreal_init (&real_zero, 0, 0);
+ sreal_init (&real_one, 1, 0);
+ sreal_init (&real_br_prob_base, REG_BR_PROB_BASE, 0);
+ sreal_init (&real_bb_freq_max, BB_FREQ_MAX, 0);
+ sreal_init (&real_one_half, 1, -1);
+ sreal_div (&real_inv_br_prob_base, &real_one, &real_br_prob_base);
+ sreal_sub (&real_almost_one, &real_one, &real_inv_br_prob_base);
+ }
mark_dfs_back_edges ();
/* Fill in the probability values in flowgraph based on the REG_BR_PROB
notes. */
FOR_EACH_BB (bb)
{
- rtx last_insn = bb->end;
+ rtx last_insn = BB_END (bb);
- if (GET_CODE (last_insn) != JUMP_INSN || !any_condjump_p (last_insn)
- /* Avoid handling of conditional jumps jumping to fallthru edge. */
- || bb->succ->succ_next == NULL)
+ if (!can_predict_insn_p (last_insn))
{
/* We can predict only conditional jumps at the moment.
Expect each edge to be equally probable.
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,
- RDIV_EXPR, EDGE_INFO (e)->back_edge_prob,
- real_br_prob_base);
+ sreal_init (&EDGE_INFO (e)->back_edge_prob, e->probability, 0);
+ sreal_mul (&EDGE_INFO (e)->back_edge_prob,
+ &EDGE_INFO (e)->back_edge_prob,
+ &real_inv_br_prob_base);
}
}
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));
+ if (sreal_compare (&freq_max, &BLOCK_INFO (bb)->frequency) < 0)
+ memcpy (&freq_max, &BLOCK_INFO (bb)->frequency, sizeof (freq_max));
+ sreal_div (&freq_max, &real_bb_freq_max, &freq_max);
FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, NULL, next_bb)
{
- REAL_VALUE_TYPE tmp;
+ sreal tmp;
- REAL_ARITHMETIC (tmp, MULT_EXPR, BLOCK_INFO (bb)->frequency,
- real_bb_freq_max);
- REAL_ARITHMETIC (tmp, RDIV_EXPR, tmp, freq_max);
- REAL_ARITHMETIC (tmp, PLUS_EXPR, tmp, real_one_half);
- bb->frequency = REAL_VALUE_UNSIGNED_FIX (tmp);
+ sreal_mul (&tmp, &BLOCK_INFO (bb)->frequency, &freq_max);
+ sreal_add (&tmp, &tmp, &real_one_half);
+ bb->frequency = sreal_to_int (&tmp);
}
free_aux_for_blocks ();
/* Decide whether function is hot, cold or unlikely executed. */
static void
-compute_function_frequency ()
+compute_function_frequency (void)
{
basic_block bb;
- if (!profile_info.count_profiles_merged
- || !flag_branch_probabilities)
+ if (!profile_info || !flag_branch_probabilities)
return;
cfun->function_frequency = FUNCTION_FREQUENCY_UNLIKELY_EXECUTED;
FOR_EACH_BB (bb)
/* Choose appropriate section for the function. */
static void
-choose_function_section ()
+choose_function_section (void)
{
if (DECL_SECTION_NAME (current_function_decl)
- || !targetm.have_named_sections)
+ || !targetm.have_named_sections
+ /* Theoretically we can split the gnu.linkonce text section too,
+ but this requires more work as the frequency needs to match
+ for all generated objects so we need to merge the frequency
+ of all instances. For now just never set frequency for these. */
+ || DECL_ONE_ONLY (current_function_decl))
return;
if (cfun->function_frequency == FUNCTION_FREQUENCY_HOT)
DECL_SECTION_NAME (current_function_decl) =
OSDN Git Service
