/*--------------------------------------------------------------------*/
/*--- Callgrind ---*/
/*--- ct_jumps.c ---*/
/*--------------------------------------------------------------------*/
/*
This file is part of Callgrind, a Valgrind tool for call tracing.
Copyright (C) 2002-2017, Josef Weidendorfer (Josef.Weidendorfer@gmx.de)
This program 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 of the
License, or (at your option) any later version.
This program 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 this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307, USA.
The GNU General Public License is contained in the file COPYING.
*/
#include "global.h"
/*------------------------------------------------------------*/
/*--- Jump Cost Center (JCC) operations, including Calls ---*/
/*------------------------------------------------------------*/
#define N_JCC_INITIAL_ENTRIES 4437
static jcc_hash current_jccs;
void CLG_(init_jcc_hash)(jcc_hash* jccs)
{
Int i;
CLG_ASSERT(jccs != 0);
jccs->size = N_JCC_INITIAL_ENTRIES;
jccs->entries = 0;
jccs->table = (jCC**) CLG_MALLOC("cl.jumps.ijh.1",
jccs->size * sizeof(jCC*));
jccs->spontaneous = 0;
for (i = 0; i < jccs->size; i++)
jccs->table[i] = 0;
}
void CLG_(copy_current_jcc_hash)(jcc_hash* dst)
{
CLG_ASSERT(dst != 0);
dst->size = current_jccs.size;
dst->entries = current_jccs.entries;
dst->table = current_jccs.table;
dst->spontaneous = current_jccs.spontaneous;
}
void CLG_(set_current_jcc_hash)(jcc_hash* h)
{
CLG_ASSERT(h != 0);
current_jccs.size = h->size;
current_jccs.entries = h->entries;
current_jccs.table = h->table;
current_jccs.spontaneous = h->spontaneous;
}
__inline__
static UInt jcc_hash_idx(BBCC* from, UInt jmp, BBCC* to, UInt size)
{
return (UInt) ( (UWord)from + 7* (UWord)to + 13*jmp) % size;
}
/* double size of jcc table */
static void resize_jcc_table(void)
{
Int i, new_size, conflicts1 = 0, conflicts2 = 0;
jCC** new_table;
UInt new_idx;
jCC *curr_jcc, *next_jcc;
new_size = 2* current_jccs.size +3;
new_table = (jCC**) CLG_MALLOC("cl.jumps.rjt.1",
new_size * sizeof(jCC*));
for (i = 0; i < new_size; i++)
new_table[i] = NULL;
for (i = 0; i < current_jccs.size; i++) {
if (current_jccs.table[i] == NULL) continue;
curr_jcc = current_jccs.table[i];
while (NULL != curr_jcc) {
next_jcc = curr_jcc->next_hash;
new_idx = jcc_hash_idx(curr_jcc->from, curr_jcc->jmp,
curr_jcc->to, new_size);
curr_jcc->next_hash = new_table[new_idx];
new_table[new_idx] = curr_jcc;
if (curr_jcc->next_hash) {
conflicts1++;
if (curr_jcc->next_hash->next_hash)
conflicts2++;
}
curr_jcc = next_jcc;
}
}
VG_(free)(current_jccs.table);
CLG_DEBUG(0, "Resize JCC Hash: %u => %d (entries %u, conflicts %d/%d)\n",
current_jccs.size, new_size,
current_jccs.entries, conflicts1, conflicts2);
current_jccs.size = new_size;
current_jccs.table = new_table;
CLG_(stat).jcc_hash_resizes++;
}
/* new jCC structure: a call was done to a BB of a BBCC
* for a spontaneous call, from is 0 (i.e. caller unknown)
*/
static jCC* new_jcc(BBCC* from, UInt jmp, BBCC* to)
{
jCC* jcc;
UInt new_idx;
/* check fill degree of jcc hash table and resize if needed (>80%) */
current_jccs.entries++;
if (10 * current_jccs.entries / current_jccs.size > 8)
resize_jcc_table();
jcc = (jCC*) CLG_MALLOC("cl.jumps.nj.1", sizeof(jCC));
jcc->from = from;
jcc->jmp = jmp;
jcc->to = to;
jcc->jmpkind = jk_Call;
jcc->call_counter = 0;
jcc->cost = 0;
/* insert into JCC chain of calling BBCC.
* This list is only used at dumping time */
if (from) {
/* Prohibit corruption by array overrun */
CLG_ASSERT((0 <= jmp) && (jmp <= from->bb->cjmp_count));
jcc->next_from = from->jmp[jmp].jcc_list;
from->jmp[jmp].jcc_list = jcc;
}
else {
jcc->next_from = current_jccs.spontaneous;
current_jccs.spontaneous = jcc;
}
/* insert into JCC hash table */
new_idx = jcc_hash_idx(from, jmp, to, current_jccs.size);
jcc->next_hash = current_jccs.table[new_idx];
current_jccs.table[new_idx] = jcc;
CLG_(stat).distinct_jccs++;
CLG_DEBUGIF(3) {
VG_(printf)(" new_jcc (now %d): %p\n",
CLG_(stat).distinct_jccs, jcc);
}
return jcc;
}
/* get the jCC for a call arc (BBCC->BBCC) */
jCC* CLG_(get_jcc)(BBCC* from, UInt jmp, BBCC* to)
{
jCC* jcc;
UInt idx;
CLG_DEBUG(5, "+ get_jcc(bbcc %p/%u => bbcc %p)\n",
from, jmp, to);
/* first check last recently used JCC */
jcc = to->lru_to_jcc;
if (jcc && (jcc->from == from) && (jcc->jmp == jmp)) {
CLG_ASSERT(to == jcc->to);
CLG_DEBUG(5,"- get_jcc: [LRU to] jcc %p\n", jcc);
return jcc;
}
jcc = from->lru_from_jcc;
if (jcc && (jcc->to == to) && (jcc->jmp == jmp)) {
CLG_ASSERT(from == jcc->from);
CLG_DEBUG(5, "- get_jcc: [LRU from] jcc %p\n", jcc);
return jcc;
}
CLG_(stat).jcc_lru_misses++;
idx = jcc_hash_idx(from, jmp, to, current_jccs.size);
jcc = current_jccs.table[idx];
while(jcc) {
if ((jcc->from == from) &&
(jcc->jmp == jmp) &&
(jcc->to == to)) break;
jcc = jcc->next_hash;
}
if (!jcc)
jcc = new_jcc(from, jmp, to);
/* set LRU */
from->lru_from_jcc = jcc;
to->lru_to_jcc = jcc;
CLG_DEBUG(5, "- get_jcc(bbcc %p => bbcc %p)\n",
from, to);
return jcc;
}