#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
#include "tree.h"
#include "rtl.h"
#include "hard-reg-set.h"
#include "basic-block.h"
#include "output.h"
#include "cfglayout.h"
#include "fibheap.h"
#include "flags.h"
#include "timevar.h"
#include "params.h"
#include "coverage.h"
#include "tree-pass.h"
static int count_insns (basic_block);
static bool ignore_bb_p (basic_block);
static bool better_p (edge, edge);
static edge find_best_successor (basic_block);
static edge find_best_predecessor (basic_block);
static int find_trace (basic_block, basic_block *);
static void tail_duplicate (void);
static void layout_superblocks (void);
static int probability_cutoff;
static int branch_ratio_cutoff;
#define seen(bb) (bb->il.rtl->visited || bb->aux)
static bool
ignore_bb_p (basic_block bb)
{
if (bb->index < NUM_FIXED_BLOCKS)
return true;
if (!maybe_hot_bb_p (bb))
return true;
return false;
}
static int
count_insns (basic_block bb)
{
rtx insn;
int n = 0;
for (insn = BB_HEAD (bb);
insn != NEXT_INSN (BB_END (bb));
insn = NEXT_INSN (insn))
if (active_insn_p (insn))
n++;
return n;
}
static bool
better_p (edge e1, edge e2)
{
if (e1->count != e2->count)
return e1->count > e2->count;
if (e1->src->frequency * e1->probability !=
e2->src->frequency * e2->probability)
return (e1->src->frequency * e1->probability
> e2->src->frequency * e2->probability);
if (e1->src != e2->src)
return e1->src->index > e2->src->index;
return e1->dest->index > e2->dest->index;
}
static edge
find_best_successor (basic_block bb)
{
edge e;
edge best = NULL;
edge_iterator ei;
FOR_EACH_EDGE (e, ei, bb->succs)
if (!best || better_p (e, best))
best = e;
if (!best || ignore_bb_p (best->dest))
return NULL;
if (best->probability <= probability_cutoff)
return NULL;
return best;
}
static edge
find_best_predecessor (basic_block bb)
{
edge e;
edge best = NULL;
edge_iterator ei;
FOR_EACH_EDGE (e, ei, bb->preds)
if (!best || better_p (e, best))
best = e;
if (!best || ignore_bb_p (best->src))
return NULL;
if (EDGE_FREQUENCY (best) * REG_BR_PROB_BASE
< bb->frequency * branch_ratio_cutoff)
return NULL;
return best;
}
static int
find_trace (basic_block bb, basic_block *trace)
{
int i = 0;
edge e;
if (dump_file)
fprintf (dump_file, "Trace seed %i [%i]", bb->index, bb->frequency);
while ((e = find_best_predecessor (bb)) != NULL)
{
basic_block bb2 = e->src;
if (seen (bb2) || (e->flags & (EDGE_DFS_BACK | EDGE_COMPLEX))
|| find_best_successor (bb2) != e)
break;
if (dump_file)
fprintf (dump_file, ",%i [%i]", bb->index, bb->frequency);
bb = bb2;
}
if (dump_file)
fprintf (dump_file, " forward %i [%i]", bb->index, bb->frequency);
trace[i++] = bb;
while ((e = find_best_successor (bb)) != NULL)
{
bb = e->dest;
if (seen (bb) || (e->flags & (EDGE_DFS_BACK | EDGE_COMPLEX))
|| find_best_predecessor (bb) != e)
break;
if (dump_file)
fprintf (dump_file, ",%i [%i]", bb->index, bb->frequency);
trace[i++] = bb;
}
if (dump_file)
fprintf (dump_file, "\n");
return i;
}
static void
tail_duplicate (void)
{
fibnode_t *blocks = XCNEWVEC (fibnode_t, last_basic_block);
basic_block *trace = XNEWVEC (basic_block, n_basic_blocks);
int *counts = XNEWVEC (int, last_basic_block);
int ninsns = 0, nduplicated = 0;
gcov_type weighted_insns = 0, traced_insns = 0;
fibheap_t heap = fibheap_new ();
gcov_type cover_insns;
int max_dup_insns;
basic_block bb;
if (profile_info && flag_branch_probabilities)
probability_cutoff = PARAM_VALUE (TRACER_MIN_BRANCH_PROBABILITY_FEEDBACK);
else
probability_cutoff = PARAM_VALUE (TRACER_MIN_BRANCH_PROBABILITY);
probability_cutoff = REG_BR_PROB_BASE / 100 * probability_cutoff;
branch_ratio_cutoff =
(REG_BR_PROB_BASE / 100 * PARAM_VALUE (TRACER_MIN_BRANCH_RATIO));
FOR_EACH_BB (bb)
{
int n = count_insns (bb);
if (!ignore_bb_p (bb))
blocks[bb->index] = fibheap_insert (heap, -bb->frequency,
bb);
counts [bb->index] = n;
ninsns += n;
weighted_insns += n * bb->frequency;
}
if (profile_info && flag_branch_probabilities)
cover_insns = PARAM_VALUE (TRACER_DYNAMIC_COVERAGE_FEEDBACK);
else
cover_insns = PARAM_VALUE (TRACER_DYNAMIC_COVERAGE);
cover_insns = (weighted_insns * cover_insns + 50) / 100;
max_dup_insns = (ninsns * PARAM_VALUE (TRACER_MAX_CODE_GROWTH) + 50) / 100;
while (traced_insns < cover_insns && nduplicated < max_dup_insns
&& !fibheap_empty (heap))
{
basic_block bb = fibheap_extract_min (heap);
int n, pos;
if (!bb)
break;
blocks[bb->index] = NULL;
if (ignore_bb_p (bb))
continue;
gcc_assert (!seen (bb));
n = find_trace (bb, trace);
bb = trace[0];
traced_insns += bb->frequency * counts [bb->index];
if (blocks[bb->index])
{
fibheap_delete_node (heap, blocks[bb->index]);
blocks[bb->index] = NULL;
}
for (pos = 1; pos < n; pos++)
{
basic_block bb2 = trace[pos];
if (blocks[bb2->index])
{
fibheap_delete_node (heap, blocks[bb2->index]);
blocks[bb2->index] = NULL;
}
traced_insns += bb2->frequency * counts [bb2->index];
if (EDGE_COUNT (bb2->preds) > 1
&& can_duplicate_block_p (bb2))
{
edge e;
basic_block old = bb2;
e = find_edge (bb, bb2);
nduplicated += counts [bb2->index];
bb2 = duplicate_block (bb2, e, bb);
blocks[old->index] =
fibheap_insert (heap, -old->frequency, old);
if (dump_file)
fprintf (dump_file, "Duplicated %i as %i [%i]\n",
old->index, bb2->index, bb2->frequency);
}
bb->aux = bb2;
bb2->il.rtl->visited = 1;
bb = bb2;
if (ignore_bb_p (bb))
break;
}
if (dump_file)
fprintf (dump_file, " covered now %.1f\n\n",
traced_insns * 100.0 / weighted_insns);
}
if (dump_file)
fprintf (dump_file, "Duplicated %i insns (%i%%)\n", nduplicated,
nduplicated * 100 / ninsns);
free (blocks);
free (trace);
free (counts);
fibheap_delete (heap);
}
static void
layout_superblocks (void)
{
basic_block end = single_succ (ENTRY_BLOCK_PTR);
basic_block bb = end->next_bb;
while (bb != EXIT_BLOCK_PTR)
{
edge_iterator ei;
edge e, best = NULL;
while (end->aux)
end = end->aux;
FOR_EACH_EDGE (e, ei, end->succs)
if (e->dest != EXIT_BLOCK_PTR
&& e->dest != single_succ (ENTRY_BLOCK_PTR)
&& !e->dest->il.rtl->visited
&& (!best || EDGE_FREQUENCY (e) > EDGE_FREQUENCY (best)))
best = e;
if (best)
{
end->aux = best->dest;
best->dest->il.rtl->visited = 1;
}
else
for (; bb != EXIT_BLOCK_PTR; bb = bb->next_bb)
{
if (!bb->il.rtl->visited)
{
end->aux = bb;
bb->il.rtl->visited = 1;
break;
}
}
}
}
void
tracer (unsigned int flags)
{
if (n_basic_blocks <= NUM_FIXED_BLOCKS + 1)
return;
cfg_layout_initialize (flags);
mark_dfs_back_edges ();
if (dump_file)
dump_flow_info (dump_file, dump_flags);
tail_duplicate ();
layout_superblocks ();
if (dump_file)
dump_flow_info (dump_file, dump_flags);
cfg_layout_finalize ();
cleanup_cfg (CLEANUP_EXPENSIVE);
}
static bool
gate_handle_tracer (void)
{
return (optimize > 0 && flag_tracer);
}
static unsigned int
rest_of_handle_tracer (void)
{
if (dump_file)
dump_flow_info (dump_file, dump_flags);
tracer (0);
cleanup_cfg (CLEANUP_EXPENSIVE);
reg_scan (get_insns (), max_reg_num ());
return 0;
}
struct tree_opt_pass pass_tracer =
{
"tracer",
gate_handle_tracer,
rest_of_handle_tracer,
NULL,
NULL,
0,
TV_TRACER,
0,
0,
0,
0,
TODO_dump_func,
'T'
};