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/*
* Copyright 2011-2014 Formal Methods and Tools, University of Twente
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <sylvan_config.h>
#include <assert.h>
#include <inttypes.h>
#include <math.h>
#include <pthread.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <avl.h>
#include <refs.h>
#include <sha2.h>
#include <sylvan.h>
#include <sylvan_common.h>
/**
* Complement handling macros
*/
#define BDD_HASMARK(s) (s&sylvan_complement?1:0)
#define BDD_TOGGLEMARK(s) (s^sylvan_complement)
#define BDD_STRIPMARK(s) (s&~sylvan_complement)
#define BDD_TRANSFERMARK(from, to) (to ^ (from & sylvan_complement))
// Equal under mark
#define BDD_EQUALM(a, b) ((((a)^(b))&(~sylvan_complement))==0)
/**
* BDD node structure
*/
typedef struct __attribute__((packed)) bddnode {
uint64_t a, b;
} * bddnode_t; // 16 bytes
#define GETNODE(bdd) ((bddnode_t)llmsset_index_to_ptr(nodes, bdd&0x000000ffffffffff))
static inline int __attribute__((unused))
bddnode_getcomp(bddnode_t n)
{
return n->a & 0x8000000000000000 ? 1 : 0;
}
static inline uint64_t
bddnode_getlow(bddnode_t n)
{
return n->b & 0x000000ffffffffff; // 40 bits
}
static inline uint64_t
bddnode_gethigh(bddnode_t n)
{
return n->a & 0x800000ffffffffff; // 40 bits plus high bit of first
}
static inline uint32_t
bddnode_getvariable(bddnode_t n)
{
return (uint32_t)(n->b >> 40);
}
static inline int
bddnode_getmark(bddnode_t n)
{
return n->a & 0x2000000000000000 ? 1 : 0;
}
static inline void
bddnode_setmark(bddnode_t n, int mark)
{
if (mark) n->a |= 0x2000000000000000;
else n->a &= 0xdfffffffffffffff;
}
static inline void
bddnode_makenode(bddnode_t n, uint32_t var, uint64_t low, uint64_t high)
{
n->a = high;
n->b = ((uint64_t)var)<<40 | low;
}
/**
* Implementation of garbage collection.
*/
/* Recursively mark BDD nodes as 'in use' */
VOID_TASK_IMPL_1(sylvan_gc_mark_rec, BDD, bdd)
{
if (bdd == sylvan_false || bdd == sylvan_true) return;
if (llmsset_mark(nodes, bdd&0x000000ffffffffff)) {
bddnode_t n = GETNODE(bdd);
SPAWN(sylvan_gc_mark_rec, bddnode_getlow(n));
CALL(sylvan_gc_mark_rec, bddnode_gethigh(n));
SYNC(sylvan_gc_mark_rec);
}
}
/**
* External references
*/
refs_table_t bdd_refs;
refs_table_t bdd_protected;
static int bdd_protected_created = 0;
BDD
sylvan_ref(BDD a)
{
if (a == sylvan_false || a == sylvan_true) return a;
refs_up(&bdd_refs, BDD_STRIPMARK(a));
return a;
}
void
sylvan_deref(BDD a)
{
if (a == sylvan_false || a == sylvan_true) return;
refs_down(&bdd_refs, BDD_STRIPMARK(a));
}
void
sylvan_protect(BDD *a)
{
if (!bdd_protected_created) {
// In C++, sometimes sylvan_protect is called before Sylvan is initialized. Just create a table.
protect_create(&bdd_protected, 4096);
bdd_protected_created = 1;
}
protect_up(&bdd_protected, (size_t)a);
}
void
sylvan_unprotect(BDD *a)
{
if (bdd_protected.refs_table != NULL) protect_down(&bdd_protected, (size_t)a);
}
size_t
sylvan_count_refs()
{
return refs_count(&bdd_refs);
}
size_t
sylvan_count_protected()
{
return protect_count(&bdd_protected);
}
/* Called during garbage collection */
VOID_TASK_0(sylvan_gc_mark_external_refs)
{
// iterate through refs hash table, mark all found
size_t count=0;
uint64_t *it = refs_iter(&bdd_refs, 0, bdd_refs.refs_size);
while (it != NULL) {
BDD to_mark = refs_next(&bdd_refs, &it, bdd_refs.refs_size);
SPAWN(sylvan_gc_mark_rec, to_mark);
count++;
}
while (count--) {
SYNC(sylvan_gc_mark_rec);
}
}
VOID_TASK_0(sylvan_gc_mark_protected)
{
// iterate through refs hash table, mark all found
size_t count=0;
uint64_t *it = protect_iter(&bdd_protected, 0, bdd_protected.refs_size);
while (it != NULL) {
BDD *to_mark = (BDD*)protect_next(&bdd_protected, &it, bdd_protected.refs_size);
SPAWN(sylvan_gc_mark_rec, *to_mark);
count++;
}
while (count--) {
SYNC(sylvan_gc_mark_rec);
}
}
/* Infrastructure for internal markings */
DECLARE_THREAD_LOCAL(bdd_refs_key, bdd_refs_internal_t);
VOID_TASK_0(bdd_refs_mark_task)
{
LOCALIZE_THREAD_LOCAL(bdd_refs_key, bdd_refs_internal_t);
size_t i, j=0;
for (i=0; i<bdd_refs_key->r_count; i++) {
if (j >= 40) {
while (j--) SYNC(sylvan_gc_mark_rec);
j=0;
}
SPAWN(sylvan_gc_mark_rec, bdd_refs_key->results[i]);
j++;
}
for (i=0; i<bdd_refs_key->s_count; i++) {
Task *t = bdd_refs_key->spawns[i];
if (!TASK_IS_STOLEN(t)) break;
if (TASK_IS_COMPLETED(t)) {
if (j >= 40) {
while (j--) SYNC(sylvan_gc_mark_rec);
j=0;
}
SPAWN(sylvan_gc_mark_rec, *(BDD*)TASK_RESULT(t));
j++;
}
}
while (j--) SYNC(sylvan_gc_mark_rec);
}
VOID_TASK_0(bdd_refs_mark)
{
TOGETHER(bdd_refs_mark_task);
}
VOID_TASK_0(bdd_refs_init_task)
{
bdd_refs_internal_t s = (bdd_refs_internal_t)malloc(sizeof(struct bdd_refs_internal));
s->r_size = 128;
s->r_count = 0;
s->s_size = 128;
s->s_count = 0;
s->results = (BDD*)malloc(sizeof(BDD) * 128);
s->spawns = (Task**)malloc(sizeof(Task*) * 128);
SET_THREAD_LOCAL(bdd_refs_key, s);
}
VOID_TASK_0(bdd_refs_init)
{
INIT_THREAD_LOCAL(bdd_refs_key);
TOGETHER(bdd_refs_init_task);
sylvan_gc_add_mark(10, TASK(bdd_refs_mark));
}
/**
* Initialize and quit functions
*/
static int granularity = 1; // default
static void
sylvan_quit_bdd()
{
refs_free(&bdd_refs);
if (bdd_protected_created) {
protect_free(&bdd_protected);
bdd_protected_created = 0;
}
}
void
sylvan_init_bdd(int _granularity)
{
sylvan_register_quit(sylvan_quit_bdd);
sylvan_gc_add_mark(10, TASK(sylvan_gc_mark_external_refs));
sylvan_gc_add_mark(10, TASK(sylvan_gc_mark_protected));
granularity = _granularity;
// Sanity check
if (sizeof(struct bddnode) != 16) {
fprintf(stderr, "Invalid size of bdd nodes: %ld\n", sizeof(struct bddnode));
exit(1);
}
refs_create(&bdd_refs, 1024);
if (!bdd_protected_created) {
protect_create(&bdd_protected, 4096);
bdd_protected_created = 1;
}
LACE_ME;
CALL(bdd_refs_init);
}
/**
* Core BDD operations
*/
BDD
sylvan_makenode(BDDVAR level, BDD low, BDD high)
{
if (low == high) return low;
// Normalization to keep canonicity
// low will have no mark
struct bddnode n;
int mark;
if (BDD_HASMARK(low)) {
mark = 1;
low = BDD_TOGGLEMARK(low);
high = BDD_TOGGLEMARK(high);
} else {
mark = 0;
}
bddnode_makenode(&n, level, low, high);
BDD result;
int created;
uint64_t index = llmsset_lookup(nodes, n.a, n.b, &created);
if (index == 0) {
LACE_ME;
bdd_refs_push(low);
bdd_refs_push(high);
sylvan_gc();
bdd_refs_pop(2);
index = llmsset_lookup(nodes, n.a, n.b, &created);
if (index == 0) {
fprintf(stderr, "BDD Unique table full, %zu of %zu buckets filled!\n", llmsset_count_marked(nodes), llmsset_get_size(nodes));
exit(1);
}
}
if (created) sylvan_stats_count(BDD_NODES_CREATED);
else sylvan_stats_count(BDD_NODES_REUSED);
result = index;
return mark ? result | sylvan_complement : result;
}
BDD
sylvan_ithvar(BDDVAR level)
{
return sylvan_makenode(level, sylvan_false, sylvan_true);
}
BDDVAR
sylvan_var(BDD bdd)
{
return bddnode_getvariable(GETNODE(bdd));
}
static BDD
node_low(BDD bdd, bddnode_t node)
{
return BDD_TRANSFERMARK(bdd, bddnode_getlow(node));
}
static BDD
node_high(BDD bdd, bddnode_t node)
{
return BDD_TRANSFERMARK(bdd, bddnode_gethigh(node));
}
BDD
sylvan_low(BDD bdd)
{
if (sylvan_isconst(bdd)) return bdd;
return node_low(bdd, GETNODE(bdd));
}
BDD
sylvan_high(BDD bdd)
{
if (sylvan_isconst(bdd)) return bdd;
return node_high(bdd, GETNODE(bdd));
}
/**
* Implementation of unary, binary and if-then-else operators.
*/
TASK_IMPL_3(BDD, sylvan_and, BDD, a, BDD, b, BDDVAR, prev_level)
{
/* Terminal cases */
if (a == sylvan_true) return b;
if (b == sylvan_true) return a;
if (a == sylvan_false) return sylvan_false;
if (b == sylvan_false) return sylvan_false;
if (a == b) return a;
if (a == BDD_TOGGLEMARK(b)) return sylvan_false;
sylvan_gc_test();
sylvan_stats_count(BDD_AND);
/* Improve for caching */
if (BDD_STRIPMARK(a) > BDD_STRIPMARK(b)) {
BDD t = b;
b = a;
a = t;
}
bddnode_t na = GETNODE(a);
bddnode_t nb = GETNODE(b);
BDDVAR va = bddnode_getvariable(na);
BDDVAR vb = bddnode_getvariable(nb);
BDDVAR level = va < vb ? va : vb;
int cachenow = granularity < 2 || prev_level == 0 ? 1 : prev_level / granularity != level / granularity;
if (cachenow) {
BDD result;
if (cache_get3(CACHE_BDD_AND, a, b, sylvan_false, &result)) {
sylvan_stats_count(BDD_AND_CACHED);
return result;
}
}
// Get cofactors
BDD aLow = a, aHigh = a;
BDD bLow = b, bHigh = b;
if (level == va) {
aLow = node_low(a, na);
aHigh = node_high(a, na);
}
if (level == vb) {
bLow = node_low(b, nb);
bHigh = node_high(b, nb);
}
// Recursive computation
BDD low=sylvan_invalid, high=sylvan_invalid, result;
int n=0;
if (aHigh == sylvan_true) {
high = bHigh;
} else if (aHigh == sylvan_false || bHigh == sylvan_false) {
high = sylvan_false;
} else if (bHigh == sylvan_true) {
high = aHigh;
} else {
bdd_refs_spawn(SPAWN(sylvan_and, aHigh, bHigh, level));
n=1;
}
if (aLow == sylvan_true) {
low = bLow;
} else if (aLow == sylvan_false || bLow == sylvan_false) {
low = sylvan_false;
} else if (bLow == sylvan_true) {
low = aLow;
} else {
low = CALL(sylvan_and, aLow, bLow, level);
}
if (n) {
bdd_refs_push(low);
high = bdd_refs_sync(SYNC(sylvan_and));
bdd_refs_pop(1);
}
result = sylvan_makenode(level, low, high);
if (cachenow) {
if (cache_put3(CACHE_BDD_AND, a, b, sylvan_false, result)) sylvan_stats_count(BDD_AND_CACHEDPUT);
}
return result;
}
TASK_IMPL_3(BDD, sylvan_xor, BDD, a, BDD, b, BDDVAR, prev_level)
{
/* Terminal cases */
if (a == sylvan_false) return b;
if (b == sylvan_false) return a;
if (a == sylvan_true) return sylvan_not(b);
if (b == sylvan_true) return sylvan_not(a);
if (a == b) return sylvan_false;
if (a == sylvan_not(b)) return sylvan_true;
sylvan_gc_test();
sylvan_stats_count(BDD_XOR);
/* Improve for caching */
if (BDD_STRIPMARK(a) > BDD_STRIPMARK(b)) {
BDD t = b;
b = a;
a = t;
}
// XOR(~A,B) => XOR(A,~B)
if (BDD_HASMARK(a)) {
a = BDD_STRIPMARK(a);
b = sylvan_not(b);
}
bddnode_t na = GETNODE(a);
bddnode_t nb = GETNODE(b);
BDDVAR va = bddnode_getvariable(na);
BDDVAR vb = bddnode_getvariable(nb);
BDDVAR level = va < vb ? va : vb;
int cachenow = granularity < 2 || prev_level == 0 ? 1 : prev_level / granularity != level / granularity;
if (cachenow) {
BDD result;
if (cache_get3(CACHE_BDD_XOR, a, b, sylvan_false, &result)) {
sylvan_stats_count(BDD_XOR_CACHED);
return result;
}
}
// Get cofactors
BDD aLow = a, aHigh = a;
BDD bLow = b, bHigh = b;
if (level == va) {
aLow = node_low(a, na);
aHigh = node_high(a, na);
}
if (level == vb) {
bLow = node_low(b, nb);
bHigh = node_high(b, nb);
}
// Recursive computation
BDD low, high, result;
bdd_refs_spawn(SPAWN(sylvan_xor, aHigh, bHigh, level));
low = CALL(sylvan_xor, aLow, bLow, level);
bdd_refs_push(low);
high = bdd_refs_sync(SYNC(sylvan_xor));
bdd_refs_pop(1);
result = sylvan_makenode(level, low, high);
if (cachenow) {
if (cache_put3(CACHE_BDD_XOR, a, b, sylvan_false, result)) sylvan_stats_count(BDD_XOR_CACHEDPUT);
}
return result;
}
TASK_IMPL_4(BDD, sylvan_ite, BDD, a, BDD, b, BDD, c, BDDVAR, prev_level)
{
/* Terminal cases */
if (a == sylvan_true) return b;
if (a == sylvan_false) return c;
if (a == b) b = sylvan_true;
if (a == sylvan_not(b)) b = sylvan_false;
if (a == c) c = sylvan_false;
if (a == sylvan_not(c)) c = sylvan_true;
if (b == c) return b;
if (b == sylvan_true && c == sylvan_false) return a;
if (b == sylvan_false && c == sylvan_true) return sylvan_not(a);
/* Cases that reduce to AND and XOR */
// ITE(A,B,0) => AND(A,B)
if (c == sylvan_false) return CALL(sylvan_and, a, b, prev_level);
// ITE(A,1,C) => ~AND(~A,~C)
if (b == sylvan_true) return sylvan_not(CALL(sylvan_and, sylvan_not(a), sylvan_not(c), prev_level));
// ITE(A,0,C) => AND(~A,C)
if (b == sylvan_false) return CALL(sylvan_and, sylvan_not(a), c, prev_level);
// ITE(A,B,1) => ~AND(A,~B)
if (c == sylvan_true) return sylvan_not(CALL(sylvan_and, a, sylvan_not(b), prev_level));
// ITE(A,B,~B) => XOR(A,~B)
if (b == sylvan_not(c)) return CALL(sylvan_xor, a, c, 0);
/* At this point, there are no more terminals */
/* Canonical for optimal cache use */
// ITE(~A,B,C) => ITE(A,C,B)
if (BDD_HASMARK(a)) {
a = BDD_STRIPMARK(a);
BDD t = c;
c = b;
b = t;
}
// ITE(A,~B,C) => ~ITE(A,B,~C)
int mark = 0;
if (BDD_HASMARK(b)) {
b = sylvan_not(b);
c = sylvan_not(c);
mark = 1;
}
bddnode_t na = GETNODE(a);
bddnode_t nb = GETNODE(b);
bddnode_t nc = GETNODE(c);
BDDVAR va = bddnode_getvariable(na);
BDDVAR vb = bddnode_getvariable(nb);
BDDVAR vc = bddnode_getvariable(nc);
// Get lowest level
BDDVAR level = vb < vc ? vb : vc;
// Fast case
if (va < level && node_low(a, na) == sylvan_false && node_high(a, na) == sylvan_true) {
BDD result = sylvan_makenode(va, c, b);
return mark ? sylvan_not(result) : result;
}
if (va < level) level = va;
sylvan_gc_test();
sylvan_stats_count(BDD_ITE);
int cachenow = granularity < 2 || prev_level == 0 ? 1 : prev_level / granularity != level / granularity;
if (cachenow) {
BDD result;
if (cache_get3(CACHE_BDD_ITE, a, b, c, &result)) {
sylvan_stats_count(BDD_ITE_CACHED);
return mark ? sylvan_not(result) : result;
}
}
// Get cofactors
BDD aLow = a, aHigh = a;
BDD bLow = b, bHigh = b;
BDD cLow = c, cHigh = c;
if (level == va) {
aLow = node_low(a, na);
aHigh = node_high(a, na);
}
if (level == vb) {
bLow = node_low(b, nb);
bHigh = node_high(b, nb);
}
if (level == vc) {
cLow = node_low(c, nc);
cHigh = node_high(c, nc);
}
// Recursive computation
BDD low=sylvan_invalid, high=sylvan_invalid, result;
int n=0;
if (aHigh == sylvan_true) {
high = bHigh;
} else if (aHigh == sylvan_false) {
high = cHigh;
} else {
bdd_refs_spawn(SPAWN(sylvan_ite, aHigh, bHigh, cHigh, level));
n=1;
}
if (aLow == sylvan_true) {
low = bLow;
} else if (aLow == sylvan_false) {
low = cLow;
} else {
low = CALL(sylvan_ite, aLow, bLow, cLow, level);
}
if (n) {
bdd_refs_push(low);
high = bdd_refs_sync(SYNC(sylvan_ite));
bdd_refs_pop(1);
}
result = sylvan_makenode(level, low, high);
if (cachenow) {
if (cache_put3(CACHE_BDD_ITE, a, b, c, result)) sylvan_stats_count(BDD_ITE_CACHEDPUT);
}
return mark ? sylvan_not(result) : result;
}
/**
* Calculate constrain a @ c
*/
TASK_IMPL_3(BDD, sylvan_constrain, BDD, a, BDD, b, BDDVAR, prev_level)
{
/* Trivial cases */
if (b == sylvan_true) return a;
if (b == sylvan_false) return sylvan_false;
if (sylvan_isconst(a)) return a;
if (a == b) return sylvan_true;
if (a == sylvan_not(b)) return sylvan_false;
/* Perhaps execute garbage collection */
sylvan_gc_test();
/* Count operation */
sylvan_stats_count(BDD_CONSTRAIN);
// a != constant and b != constant
bddnode_t na = GETNODE(a);
bddnode_t nb = GETNODE(b);
BDDVAR va = bddnode_getvariable(na);
BDDVAR vb = bddnode_getvariable(nb);
BDDVAR level = va < vb ? va : vb;
// CONSULT CACHE
int cachenow = granularity < 2 || prev_level == 0 ? 1 : prev_level / granularity != level / granularity;
if (cachenow) {
BDD result;
if (cache_get3(CACHE_BDD_CONSTRAIN, a, b, 0, &result)) {
sylvan_stats_count(BDD_CONSTRAIN_CACHED);
return result;
}
}
// DETERMINE TOP BDDVAR AND COFACTORS
BDD aLow, aHigh, bLow, bHigh;
if (level == va) {
aLow = node_low(a, na);
aHigh = node_high(a, na);
} else {
aLow = aHigh = a;
}
if (level == vb) {
bLow = node_low(b, nb);
bHigh = node_high(b, nb);
} else {
bLow = bHigh = b;
}
BDD result;
BDD low=sylvan_invalid, high=sylvan_invalid;
if (bLow == sylvan_false) return CALL(sylvan_constrain, aHigh, bHigh, level);
if (bLow == sylvan_true) {
if (bHigh == sylvan_false) return aLow;
if (bHigh == sylvan_true) {
result = sylvan_makenode(level, aLow, bHigh);
} else {
high = CALL(sylvan_constrain, aHigh, bHigh, level);
result = sylvan_makenode(level, aLow, high);
}
} else {
if (bHigh == sylvan_false) return CALL(sylvan_constrain, aLow, bLow, level);
if (bHigh == sylvan_true) {
low = CALL(sylvan_constrain, aLow, bLow, level);
result = sylvan_makenode(level, low, bHigh);
} else {
bdd_refs_spawn(SPAWN(sylvan_constrain, aLow, bLow, level));
high = CALL(sylvan_constrain, aHigh, bHigh, level);
bdd_refs_push(high);
low = bdd_refs_sync(SYNC(sylvan_constrain));
bdd_refs_pop(1);
result = sylvan_makenode(level, low, high);
}
}
if (cachenow) {
if (cache_put3(CACHE_BDD_CONSTRAIN, a, b, 0, result)) sylvan_stats_count(BDD_CONSTRAIN_CACHEDPUT);
}
return result;
}
/**
* Calculate restrict a @ b
*/
TASK_IMPL_3(BDD, sylvan_restrict, BDD, a, BDD, b, BDDVAR, prev_level)
{
/* Trivial cases */
if (b == sylvan_true) return a;
if (b == sylvan_false) return sylvan_false;
if (sylvan_isconst(a)) return a;
if (a == b) return sylvan_true;
if (a == sylvan_not(b)) return sylvan_false;
/* Perhaps execute garbage collection */
sylvan_gc_test();
/* Count operation */
sylvan_stats_count(BDD_RESTRICT);
// a != constant and b != constant
bddnode_t na = GETNODE(a);
bddnode_t nb = GETNODE(b);
BDDVAR va = bddnode_getvariable(na);
BDDVAR vb = bddnode_getvariable(nb);
BDDVAR level = va < vb ? va : vb;
/* Consult cache */
int cachenow = granularity < 2 || prev_level == 0 ? 1 : prev_level / granularity != level / granularity;
if (cachenow) {
BDD result;
if (cache_get3(CACHE_BDD_RESTRICT, a, b, 0, &result)) {
sylvan_stats_count(BDD_RESTRICT_CACHED);
return result;
}
}
BDD result;
if (vb < va) {
BDD c = CALL(sylvan_ite, node_low(b,nb), sylvan_true, node_high(b,nb), 0);
bdd_refs_push(c);
result = CALL(sylvan_restrict, a, c, level);
bdd_refs_pop(1);
} else {
BDD aLow=node_low(a,na),aHigh=node_high(a,na),bLow=b,bHigh=b;
if (va == vb) {
bLow = node_low(b,nb);
bHigh = node_high(b,nb);
}
if (bLow == sylvan_false) {
result = CALL(sylvan_restrict, aHigh, bHigh, level);
} else if (bHigh == sylvan_false) {
result = CALL(sylvan_restrict, aLow, bLow, level);
} else {
bdd_refs_spawn(SPAWN(sylvan_restrict, aLow, bLow, level));
BDD high = CALL(sylvan_restrict, aHigh, bHigh, level);
bdd_refs_push(high);
BDD low = bdd_refs_sync(SYNC(sylvan_restrict));
bdd_refs_pop(1);
result = sylvan_makenode(level, low, high);
}
}
if (cachenow) {
if (cache_put3(CACHE_BDD_RESTRICT, a, b, 0, result)) sylvan_stats_count(BDD_RESTRICT_CACHEDPUT);
}
return result;
}
/**
* Calculates \exists variables . a
*/
TASK_IMPL_3(BDD, sylvan_exists, BDD, a, BDD, variables, BDDVAR, prev_level)
{
/* Terminal cases */
if (a == sylvan_true) return sylvan_true;
if (a == sylvan_false) return sylvan_false;
if (sylvan_set_isempty(variables)) return a;
// a != constant
bddnode_t na = GETNODE(a);
BDDVAR level = bddnode_getvariable(na);
bddnode_t nv = GETNODE(variables);
BDDVAR vv = bddnode_getvariable(nv);
while (vv < level) {
variables = node_high(variables, nv);
if (sylvan_set_isempty(variables)) return a;
nv = GETNODE(variables);
vv = bddnode_getvariable(nv);
}
sylvan_gc_test();
sylvan_stats_count(BDD_EXISTS);
int cachenow = granularity < 2 || prev_level == 0 ? 1 : prev_level / granularity != level / granularity;
if (cachenow) {
BDD result;
if (cache_get3(CACHE_BDD_EXISTS, a, variables, 0, &result)) {
sylvan_stats_count(BDD_EXISTS_CACHED);
return result;
}
}
// Get cofactors
BDD aLow = node_low(a, na);
BDD aHigh = node_high(a, na);
BDD result;
if (vv == level) {
// level is in variable set, perform abstraction
if (aLow == sylvan_true || aHigh == sylvan_true || aLow == sylvan_not(aHigh)) {
result = sylvan_true;
} else {
BDD _v = sylvan_set_next(variables);
BDD low = CALL(sylvan_exists, aLow, _v, level);
if (low == sylvan_true) {
result = sylvan_true;
} else {
bdd_refs_push(low);
BDD high = CALL(sylvan_exists, aHigh, _v, level);
if (high == sylvan_true) {
result = sylvan_true;
bdd_refs_pop(1);
} else if (low == sylvan_false && high == sylvan_false) {
result = sylvan_false;
bdd_refs_pop(1);
} else {
bdd_refs_push(high);
result = sylvan_or(low, high);
bdd_refs_pop(2);
}
}
}
} else {
// level is not in variable set
BDD low, high;
bdd_refs_spawn(SPAWN(sylvan_exists, aHigh, variables, level));
low = CALL(sylvan_exists, aLow, variables, level);
bdd_refs_push(low);
high = bdd_refs_sync(SYNC(sylvan_exists));
bdd_refs_pop(1);
result = sylvan_makenode(level, low, high);
}
if (cachenow) {
if (cache_put3(CACHE_BDD_EXISTS, a, variables, 0, result)) sylvan_stats_count(BDD_EXISTS_CACHEDPUT);
}
return result;
}
/**
* Calculate exists(a AND b, v)
*/
TASK_IMPL_4(BDD, sylvan_and_exists, BDD, a, BDD, b, BDDSET, v, BDDVAR, prev_level)
{
/* Terminal cases */
if (a == sylvan_false) return sylvan_false;
if (b == sylvan_false) return sylvan_false;
if (a == sylvan_not(b)) return sylvan_false;
if (a == sylvan_true && b == sylvan_true) return sylvan_true;
/* Cases that reduce to "exists" and "and" */
if (a == sylvan_true) return CALL(sylvan_exists, b, v, 0);
if (b == sylvan_true) return CALL(sylvan_exists, a, v, 0);
if (a == b) return CALL(sylvan_exists, a, v, 0);
if (sylvan_set_isempty(v)) return sylvan_and(a, b);
/* At this point, a and b are proper nodes, and v is non-empty */
/* Improve for caching */
if (BDD_STRIPMARK(a) > BDD_STRIPMARK(b)) {
BDD t = b;
b = a;
a = t;
}
/* Maybe perform garbage collection */
sylvan_gc_test();
sylvan_stats_count(BDD_AND_EXISTS);
// a != constant
bddnode_t na = GETNODE(a);
bddnode_t nb = GETNODE(b);
bddnode_t nv = GETNODE(v);
BDDVAR va = bddnode_getvariable(na);
BDDVAR vb = bddnode_getvariable(nb);
BDDVAR vv = bddnode_getvariable(nv);
BDDVAR level = va < vb ? va : vb;
/* Skip levels in v that are not in a and b */
while (vv < level) {
v = node_high(v, nv); // get next variable in conjunction
if (sylvan_set_isempty(v)) return sylvan_and(a, b);
nv = GETNODE(v);
vv = bddnode_getvariable(nv);
}
BDD result;
int cachenow = granularity < 2 || prev_level == 0 ? 1 : prev_level / granularity != level / granularity;
if (cachenow) {
if (cache_get3(CACHE_BDD_AND_EXISTS, a, b, v, &result)) {
sylvan_stats_count(BDD_AND_EXISTS_CACHED);
return result;
}
}
// Get cofactors
BDD aLow, aHigh, bLow, bHigh;
if (level == va) {
aLow = node_low(a, na);
aHigh = node_high(a, na);
} else {
aLow = a;
aHigh = a;
}
if (level == vb) {
bLow = node_low(b, nb);
bHigh = node_high(b, nb);
} else {
bLow = b;
bHigh = b;
}
if (level == vv) {
// level is in variable set, perform abstraction
BDD _v = node_high(v, nv);
BDD low = CALL(sylvan_and_exists, aLow, bLow, _v, level);
if (low == sylvan_true || low == aHigh || low == bHigh) {
result = low;
} else {
bdd_refs_push(low);
BDD high;
if (low == sylvan_not(aHigh)) {
high = CALL(sylvan_exists, bHigh, _v, 0);
} else if (low == sylvan_not(bHigh)) {
high = CALL(sylvan_exists, aHigh, _v, 0);
} else {
high = CALL(sylvan_and_exists, aHigh, bHigh, _v, level);
}
if (high == sylvan_true) {
result = sylvan_true;
bdd_refs_pop(1);
} else if (high == sylvan_false) {
result = low;
bdd_refs_pop(1);
} else if (low == sylvan_false) {
result = high;
bdd_refs_pop(1);
} else {
bdd_refs_push(high);
result = sylvan_or(low, high);
bdd_refs_pop(2);
}
}
} else {
// level is not in variable set
bdd_refs_spawn(SPAWN(sylvan_and_exists, aHigh, bHigh, v, level));
BDD low = CALL(sylvan_and_exists, aLow, bLow, v, level);
bdd_refs_push(low);
BDD high = bdd_refs_sync(SYNC(sylvan_and_exists));
bdd_refs_pop(1);
result = sylvan_makenode(level, low, high);
}
if (cachenow) {
if (cache_put3(CACHE_BDD_AND_EXISTS, a, b, v, result)) sylvan_stats_count(BDD_AND_EXISTS_CACHEDPUT);
}
return result;
}
TASK_IMPL_4(BDD, sylvan_relnext, BDD, a, BDD, b, BDDSET, vars, BDDVAR, prev_level)
{
/* Compute R(s) = \exists x: A(x) \and B(x,s) with support(result) = s, support(A) = s, support(B) = s+t
* if vars == sylvan_false, then every level is in s or t
* any other levels (outside s,t) in B are ignored / existentially quantified
*/
/* Terminals */
if (a == sylvan_true && b == sylvan_true) return sylvan_true;
if (a == sylvan_false) return sylvan_false;
if (b == sylvan_false) return sylvan_false;
if (sylvan_set_isempty(vars)) return a;
/* Perhaps execute garbage collection */
sylvan_gc_test();
/* Count operation */
sylvan_stats_count(BDD_RELNEXT);
/* Determine top level */
bddnode_t na = sylvan_isconst(a) ? 0 : GETNODE(a);
bddnode_t nb = sylvan_isconst(b) ? 0 : GETNODE(b);
BDDVAR va = na ? bddnode_getvariable(na) : 0xffffffff;
BDDVAR vb = nb ? bddnode_getvariable(nb) : 0xffffffff;
BDDVAR level = va < vb ? va : vb;
/* Skip vars */
int is_s_or_t = 0;
bddnode_t nv = 0;
if (vars == sylvan_false) {
is_s_or_t = 1;
} else {
nv = GETNODE(vars);
for (;;) {
/* check if level is s/t */
BDDVAR vv = bddnode_getvariable(nv);
if (level == vv || (level^1) == vv) {
is_s_or_t = 1;
break;
}
/* check if level < s/t */
if (level < vv) break;
vars = node_high(vars, nv); // get next in vars
if (sylvan_set_isempty(vars)) return a;
nv = GETNODE(vars);
}
}
/* Consult cache */
int cachenow = granularity < 2 || prev_level == 0 ? 1 : prev_level / granularity != level / granularity;
if (cachenow) {
BDD result;
if (cache_get3(CACHE_BDD_RELNEXT, a, b, vars, &result)) {
sylvan_stats_count(BDD_RELNEXT_CACHED);
return result;
}
}
BDD result;
if (is_s_or_t) {
/* Get s and t */
BDDVAR s = level & (~1);
BDDVAR t = s+1;
BDD a0, a1, b0, b1;
if (na && va == s) {
a0 = node_low(a, na);
a1 = node_high(a, na);
} else {
a0 = a1 = a;
}
if (nb && vb == s) {
b0 = node_low(b, nb);
b1 = node_high(b, nb);
} else {
b0 = b1 = b;
}
BDD b00, b01, b10, b11;
if (!sylvan_isconst(b0)) {
bddnode_t nb0 = GETNODE(b0);
if (bddnode_getvariable(nb0) == t) {
b00 = node_low(b0, nb0);
b01 = node_high(b0, nb0);
} else {
b00 = b01 = b0;
}
} else {
b00 = b01 = b0;
}
if (!sylvan_isconst(b1)) {
bddnode_t nb1 = GETNODE(b1);
if (bddnode_getvariable(nb1) == t) {
b10 = node_low(b1, nb1);
b11 = node_high(b1, nb1);
} else {
b10 = b11 = b1;
}
} else {
b10 = b11 = b1;
}
BDD _vars = vars == sylvan_false ? sylvan_false : node_high(vars, nv);
bdd_refs_spawn(SPAWN(sylvan_relnext, a0, b00, _vars, level));
bdd_refs_spawn(SPAWN(sylvan_relnext, a1, b10, _vars, level));
bdd_refs_spawn(SPAWN(sylvan_relnext, a0, b01, _vars, level));
bdd_refs_spawn(SPAWN(sylvan_relnext, a1, b11, _vars, level));
BDD f = bdd_refs_sync(SYNC(sylvan_relnext)); bdd_refs_push(f);
BDD e = bdd_refs_sync(SYNC(sylvan_relnext)); bdd_refs_push(e);
BDD d = bdd_refs_sync(SYNC(sylvan_relnext)); bdd_refs_push(d);
BDD c = bdd_refs_sync(SYNC(sylvan_relnext)); bdd_refs_push(c);
bdd_refs_spawn(SPAWN(sylvan_ite, c, sylvan_true, d, 0)); /* a0 b00 \or a1 b01 */
bdd_refs_spawn(SPAWN(sylvan_ite, e, sylvan_true, f, 0)); /* a0 b01 \or a1 b11 */
/* R1 */ d = bdd_refs_sync(SYNC(sylvan_ite)); bdd_refs_push(d);
/* R0 */ c = bdd_refs_sync(SYNC(sylvan_ite)); // not necessary: bdd_refs_push(c);
bdd_refs_pop(5);
result = sylvan_makenode(s, c, d);
} else {
/* Variable not in vars! Take a, quantify b */
BDD a0, a1, b0, b1;
if (na && va == level) {
a0 = node_low(a, na);
a1 = node_high(a, na);
} else {
a0 = a1 = a;
}
if (nb && vb == level) {
b0 = node_low(b, nb);
b1 = node_high(b, nb);
} else {
b0 = b1 = b;
}
if (b0 != b1) {
if (a0 == a1) {
/* Quantify "b" variables */
bdd_refs_spawn(SPAWN(sylvan_relnext, a0, b0, vars, level));
bdd_refs_spawn(SPAWN(sylvan_relnext, a1, b1, vars, level));
BDD r1 = bdd_refs_sync(SYNC(sylvan_relnext));
bdd_refs_push(r1);
BDD r0 = bdd_refs_sync(SYNC(sylvan_relnext));
bdd_refs_push(r0);
result = sylvan_or(r0, r1);
bdd_refs_pop(2);
} else {
/* Quantify "b" variables, but keep "a" variables */
bdd_refs_spawn(SPAWN(sylvan_relnext, a0, b0, vars, level));
bdd_refs_spawn(SPAWN(sylvan_relnext, a0, b1, vars, level));
bdd_refs_spawn(SPAWN(sylvan_relnext, a1, b0, vars, level));
bdd_refs_spawn(SPAWN(sylvan_relnext, a1, b1, vars, level));
BDD r11 = bdd_refs_sync(SYNC(sylvan_relnext));
bdd_refs_push(r11);
BDD r10 = bdd_refs_sync(SYNC(sylvan_relnext));
bdd_refs_push(r10);
BDD r01 = bdd_refs_sync(SYNC(sylvan_relnext));
bdd_refs_push(r01);
BDD r00 = bdd_refs_sync(SYNC(sylvan_relnext));
bdd_refs_push(r00);
bdd_refs_spawn(SPAWN(sylvan_ite, r00, sylvan_true, r01, 0));
bdd_refs_spawn(SPAWN(sylvan_ite, r10, sylvan_true, r11, 0));
BDD r1 = bdd_refs_sync(SYNC(sylvan_ite));
bdd_refs_push(r1);
BDD r0 = bdd_refs_sync(SYNC(sylvan_ite));
bdd_refs_pop(5);
result = sylvan_makenode(level, r0, r1);
}
} else {
/* Keep "a" variables */
bdd_refs_spawn(SPAWN(sylvan_relnext, a0, b0, vars, level));
bdd_refs_spawn(SPAWN(sylvan_relnext, a1, b1, vars, level));
BDD r1 = bdd_refs_sync(SYNC(sylvan_relnext));
bdd_refs_push(r1);
BDD r0 = bdd_refs_sync(SYNC(sylvan_relnext));
bdd_refs_pop(1);
result = sylvan_makenode(level, r0, r1);
}
}
if (cachenow) {
if (cache_put3(CACHE_BDD_RELNEXT, a, b, vars, result)) sylvan_stats_count(BDD_RELNEXT_CACHEDPUT);
}
return result;
}
TASK_IMPL_4(BDD, sylvan_relprev, BDD, a, BDD, b, BDDSET, vars, BDDVAR, prev_level)
{
/* Compute \exists x: A(s,x) \and B(x,t)
* if vars == sylvan_false, then every level is in s or t
* any other levels (outside s,t) in A are ignored / existentially quantified
*/
/* Terminals */
if (a == sylvan_true && b == sylvan_true) return sylvan_true;
if (a == sylvan_false) return sylvan_false;
if (b == sylvan_false) return sylvan_false;
if (sylvan_set_isempty(vars)) return b;
/* Perhaps execute garbage collection */
sylvan_gc_test();
/* Count operation */
sylvan_stats_count(BDD_RELPREV);
/* Determine top level */
bddnode_t na = sylvan_isconst(a) ? 0 : GETNODE(a);
bddnode_t nb = sylvan_isconst(b) ? 0 : GETNODE(b);
BDDVAR va = na ? bddnode_getvariable(na) : 0xffffffff;
BDDVAR vb = nb ? bddnode_getvariable(nb) : 0xffffffff;
BDDVAR level = va < vb ? va : vb;
/* Skip vars */
int is_s_or_t = 0;
bddnode_t nv = 0;
if (vars == sylvan_false) {
is_s_or_t = 1;
} else {
nv = GETNODE(vars);
for (;;) {
/* check if level is s/t */
BDDVAR vv = bddnode_getvariable(nv);
if (level == vv || (level^1) == vv) {
is_s_or_t = 1;
break;
}
/* check if level < s/t */
if (level < vv) break;
vars = node_high(vars, nv); // get next in vars
if (sylvan_set_isempty(vars)) return b;
nv = GETNODE(vars);
}
}
/* Consult cache */
int cachenow = granularity < 2 || prev_level == 0 ? 1 : prev_level / granularity != level / granularity;
if (cachenow) {
BDD result;
if (cache_get3(CACHE_BDD_RELPREV, a, b, vars, &result)) {
sylvan_stats_count(BDD_RELPREV_CACHED);
return result;
}
}
BDD result;
if (is_s_or_t) {
/* Get s and t */
BDDVAR s = level & (~1);
BDDVAR t = s+1;
BDD a0, a1, b0, b1;
if (na && va == s) {
a0 = node_low(a, na);
a1 = node_high(a, na);
} else {
a0 = a1 = a;
}
if (nb && vb == s) {
b0 = node_low(b, nb);
b1 = node_high(b, nb);
} else {
b0 = b1 = b;
}
BDD a00, a01, a10, a11;
if (!sylvan_isconst(a0)) {
bddnode_t na0 = GETNODE(a0);
if (bddnode_getvariable(na0) == t) {
a00 = node_low(a0, na0);
a01 = node_high(a0, na0);
} else {
a00 = a01 = a0;
}
} else {
a00 = a01 = a0;
}
if (!sylvan_isconst(a1)) {
bddnode_t na1 = GETNODE(a1);
if (bddnode_getvariable(na1) == t) {
a10 = node_low(a1, na1);
a11 = node_high(a1, na1);
} else {
a10 = a11 = a1;
}
} else {
a10 = a11 = a1;
}
BDD b00, b01, b10, b11;
if (!sylvan_isconst(b0)) {
bddnode_t nb0 = GETNODE(b0);
if (bddnode_getvariable(nb0) == t) {
b00 = node_low(b0, nb0);
b01 = node_high(b0, nb0);
} else {
b00 = b01 = b0;
}
} else {
b00 = b01 = b0;
}
if (!sylvan_isconst(b1)) {
bddnode_t nb1 = GETNODE(b1);
if (bddnode_getvariable(nb1) == t) {
b10 = node_low(b1, nb1);
b11 = node_high(b1, nb1);
} else {
b10 = b11 = b1;
}
} else {
b10 = b11 = b1;
}
BDD _vars;
if (vars != sylvan_false) {
_vars = node_high(vars, nv);
if (sylvan_set_var(_vars) == t) _vars = sylvan_set_next(_vars);
} else {
_vars = sylvan_false;
}
if (b00 == b01) {
bdd_refs_spawn(SPAWN(sylvan_relprev, a00, b0, _vars, level));
bdd_refs_spawn(SPAWN(sylvan_relprev, a10, b0, _vars, level));
} else {
bdd_refs_spawn(SPAWN(sylvan_relprev, a00, b00, _vars, level));
bdd_refs_spawn(SPAWN(sylvan_relprev, a00, b01, _vars, level));
bdd_refs_spawn(SPAWN(sylvan_relprev, a10, b00, _vars, level));
bdd_refs_spawn(SPAWN(sylvan_relprev, a10, b01, _vars, level));
}
if (b10 == b11) {
bdd_refs_spawn(SPAWN(sylvan_relprev, a01, b1, _vars, level));
bdd_refs_spawn(SPAWN(sylvan_relprev, a11, b1, _vars, level));
} else {
bdd_refs_spawn(SPAWN(sylvan_relprev, a01, b10, _vars, level));
bdd_refs_spawn(SPAWN(sylvan_relprev, a01, b11, _vars, level));
bdd_refs_spawn(SPAWN(sylvan_relprev, a11, b10, _vars, level));
bdd_refs_spawn(SPAWN(sylvan_relprev, a11, b11, _vars, level));
}
BDD r00, r01, r10, r11;
if (b10 == b11) {
r11 = bdd_refs_push(bdd_refs_sync(SYNC(sylvan_relprev)));
r01 = bdd_refs_push(bdd_refs_sync(SYNC(sylvan_relprev)));
} else {
BDD r111 = bdd_refs_push(bdd_refs_sync(SYNC(sylvan_relprev)));
BDD r110 = bdd_refs_push(bdd_refs_sync(SYNC(sylvan_relprev)));
r11 = sylvan_makenode(t, r110, r111);
bdd_refs_pop(2);
bdd_refs_push(r11);
BDD r011 = bdd_refs_push(bdd_refs_sync(SYNC(sylvan_relprev)));
BDD r010 = bdd_refs_push(bdd_refs_sync(SYNC(sylvan_relprev)));
r01 = sylvan_makenode(t, r010, r011);
bdd_refs_pop(2);
bdd_refs_push(r01);
}
if (b00 == b01) {
r10 = bdd_refs_push(bdd_refs_sync(SYNC(sylvan_relprev)));
r00 = bdd_refs_push(bdd_refs_sync(SYNC(sylvan_relprev)));
} else {
BDD r101 = bdd_refs_push(bdd_refs_sync(SYNC(sylvan_relprev)));
BDD r100 = bdd_refs_push(bdd_refs_sync(SYNC(sylvan_relprev)));
r10 = sylvan_makenode(t, r100, r101);
bdd_refs_pop(2);
bdd_refs_push(r10);
BDD r001 = bdd_refs_push(bdd_refs_sync(SYNC(sylvan_relprev)));
BDD r000 = bdd_refs_push(bdd_refs_sync(SYNC(sylvan_relprev)));
r00 = sylvan_makenode(t, r000, r001);
bdd_refs_pop(2);
bdd_refs_push(r00);
}
bdd_refs_spawn(SPAWN(sylvan_and, sylvan_not(r00), sylvan_not(r01), 0));
bdd_refs_spawn(SPAWN(sylvan_and, sylvan_not(r10), sylvan_not(r11), 0));
BDD r1 = sylvan_not(bdd_refs_push(bdd_refs_sync(SYNC(sylvan_and))));
BDD r0 = sylvan_not(bdd_refs_sync(SYNC(sylvan_and)));
bdd_refs_pop(5);
result = sylvan_makenode(s, r0, r1);
} else {
BDD a0, a1, b0, b1;
if (na && va == level) {
a0 = node_low(a, na);
a1 = node_high(a, na);
} else {
a0 = a1 = a;
}
if (nb && vb == level) {
b0 = node_low(b, nb);
b1 = node_high(b, nb);
} else {
b0 = b1 = b;
}
if (a0 != a1) {
if (b0 == b1) {
/* Quantify "a" variables */
bdd_refs_spawn(SPAWN(sylvan_relprev, a0, b0, vars, level));
bdd_refs_spawn(SPAWN(sylvan_relprev, a1, b1, vars, level));
BDD r1 = bdd_refs_sync(SYNC(sylvan_relprev));
bdd_refs_push(r1);
BDD r0 = bdd_refs_sync(SYNC(sylvan_relprev));
bdd_refs_push(r0);
result = CALL(sylvan_ite, r0, sylvan_true, r1, 0);
bdd_refs_pop(2);
} else {
/* Quantify "a" variables, but keep "b" variables */
bdd_refs_spawn(SPAWN(sylvan_relnext, a0, b0, vars, level));
bdd_refs_spawn(SPAWN(sylvan_relnext, a1, b0, vars, level));
bdd_refs_spawn(SPAWN(sylvan_relnext, a0, b1, vars, level));
bdd_refs_spawn(SPAWN(sylvan_relnext, a1, b1, vars, level));
BDD r11 = bdd_refs_sync(SYNC(sylvan_relnext));
bdd_refs_push(r11);
BDD r01 = bdd_refs_sync(SYNC(sylvan_relnext));
bdd_refs_push(r01);
BDD r10 = bdd_refs_sync(SYNC(sylvan_relnext));
bdd_refs_push(r10);
BDD r00 = bdd_refs_sync(SYNC(sylvan_relnext));
bdd_refs_push(r00);
bdd_refs_spawn(SPAWN(sylvan_ite, r00, sylvan_true, r10, 0));
bdd_refs_spawn(SPAWN(sylvan_ite, r01, sylvan_true, r11, 0));
BDD r1 = bdd_refs_sync(SYNC(sylvan_ite));
bdd_refs_push(r1);
BDD r0 = bdd_refs_sync(SYNC(sylvan_ite));
bdd_refs_pop(5);
result = sylvan_makenode(level, r0, r1);
}
} else {
bdd_refs_spawn(SPAWN(sylvan_relprev, a0, b0, vars, level));
bdd_refs_spawn(SPAWN(sylvan_relprev, a1, b1, vars, level));
BDD r1 = bdd_refs_sync(SYNC(sylvan_relprev));
bdd_refs_push(r1);
BDD r0 = bdd_refs_sync(SYNC(sylvan_relprev));
bdd_refs_pop(1);
result = sylvan_makenode(level, r0, r1);
}
}
if (cachenow) {
if (cache_put3(CACHE_BDD_RELPREV, a, b, vars, result)) sylvan_stats_count(BDD_RELPREV_CACHEDPUT);
}
return result;
}
/**
* Computes the transitive closure by traversing the BDD recursively.
* See Y. Matsunaga, P. C. McGeer, R. K. Brayton
* On Computing the Transitive Closre of a State Transition Relation
* 30th ACM Design Automation Conference, 1993.
*/
TASK_IMPL_2(BDD, sylvan_closure, BDD, a, BDDVAR, prev_level)
{
/* Terminals */
if (a == sylvan_true) return a;
if (a == sylvan_false) return a;
/* Perhaps execute garbage collection */
sylvan_gc_test();
/* Count operation */
sylvan_stats_count(BDD_CLOSURE);
/* Determine top level */
bddnode_t n = GETNODE(a);
BDDVAR level = bddnode_getvariable(n);
/* Consult cache */
int cachenow = granularity < 2 || prev_level == 0 ? 1 : prev_level / granularity != level / granularity;
if (cachenow) {
BDD result;
if (cache_get3(CACHE_BDD_CLOSURE, a, 0, 0, &result)) {
sylvan_stats_count(BDD_CLOSURE_CACHED);
return result;
}
}
BDDVAR s = level & (~1);
BDDVAR t = s+1;
BDD a0, a1;
if (level == s) {
a0 = node_low(a, n);
a1 = node_high(a, n);
} else {
a0 = a1 = a;
}
BDD a00, a01, a10, a11;
if (!sylvan_isconst(a0)) {
bddnode_t na0 = GETNODE(a0);
if (bddnode_getvariable(na0) == t) {
a00 = node_low(a0, na0);
a01 = node_high(a0, na0);
} else {
a00 = a01 = a0;
}
} else {
a00 = a01 = a0;
}
if (!sylvan_isconst(a1)) {
bddnode_t na1 = GETNODE(a1);
if (bddnode_getvariable(na1) == t) {
a10 = node_low(a1, na1);
a11 = node_high(a1, na1);
} else {
a10 = a11 = a1;
}
} else {
a10 = a11 = a1;
}
BDD u1 = CALL(sylvan_closure, a11, level);
bdd_refs_push(u1);
/* u3 = */ bdd_refs_spawn(SPAWN(sylvan_relprev, a01, u1, sylvan_false, level));
BDD u2 = CALL(sylvan_relprev, u1, a10, sylvan_false, level);
bdd_refs_push(u2);
BDD e = CALL(sylvan_relprev, a01, u2, sylvan_false, level);
bdd_refs_push(e);
e = CALL(sylvan_ite, a00, sylvan_true, e, level);
bdd_refs_pop(1);
bdd_refs_push(e);
e = CALL(sylvan_closure, e, level);
bdd_refs_pop(1);
bdd_refs_push(e);
BDD g = CALL(sylvan_relprev, u2, e, sylvan_false, level);
bdd_refs_push(g);
BDD u3 = bdd_refs_sync(SYNC(sylvan_relprev));
bdd_refs_push(u3);
BDD f = CALL(sylvan_relprev, e, u3, sylvan_false, level);
bdd_refs_push(f);
BDD h = CALL(sylvan_relprev, u2, f, sylvan_false, level);
bdd_refs_push(h);
h = CALL(sylvan_ite, u1, sylvan_true, h, level);
bdd_refs_pop(1);
bdd_refs_push(h);
BDD r0, r1;
/* R0 */ r0 = sylvan_makenode(t, e, f);
bdd_refs_pop(7);
bdd_refs_push(r0);
/* R1 */ r1 = sylvan_makenode(t, g, h);
bdd_refs_pop(1);
BDD result = sylvan_makenode(s, r0, r1);
if (cachenow) {
if (cache_put3(CACHE_BDD_CLOSURE, a, 0, 0, result)) sylvan_stats_count(BDD_CLOSURE_CACHEDPUT);
}
return result;
}
/**
* Function composition
*/
TASK_IMPL_3(BDD, sylvan_compose, BDD, a, BDDMAP, map, BDDVAR, prev_level)
{
/* Trivial cases */
if (a == sylvan_false || a == sylvan_true) return a;
if (sylvan_map_isempty(map)) return a;
/* Perhaps execute garbage collection */
sylvan_gc_test();
/* Count operation */
sylvan_stats_count(BDD_COMPOSE);
/* Determine top level */
bddnode_t n = GETNODE(a);
BDDVAR level = bddnode_getvariable(n);
/* Skip map */
bddnode_t map_node = GETNODE(map);
BDDVAR map_var = bddnode_getvariable(map_node);
while (map_var < level) {
map = node_low(map, map_node);
if (sylvan_map_isempty(map)) return a;
map_node = GETNODE(map);
map_var = bddnode_getvariable(map_node);
}
/* Consult cache */
int cachenow = granularity < 2 || prev_level == 0 ? 1 : prev_level / granularity != level / granularity;
if (cachenow) {
BDD result;
if (cache_get3(CACHE_BDD_COMPOSE, a, map, 0, &result)) {
sylvan_stats_count(BDD_COMPOSE_CACHED);
return result;
}
}
/* Recursively calculate low and high */
bdd_refs_spawn(SPAWN(sylvan_compose, node_low(a, n), map, level));
BDD high = CALL(sylvan_compose, node_high(a, n), map, level);
bdd_refs_push(high);
BDD low = bdd_refs_sync(SYNC(sylvan_compose));
bdd_refs_push(low);
/* Calculate result */
BDD root = map_var == level ? node_high(map, map_node) : sylvan_ithvar(level);
bdd_refs_push(root);
BDD result = CALL(sylvan_ite, root, high, low, 0);
bdd_refs_pop(3);
if (cachenow) {
if (cache_put3(CACHE_BDD_COMPOSE, a, map, 0, result)) sylvan_stats_count(BDD_COMPOSE_CACHEDPUT);
}
return result;
}
/**
* Count number of nodes in BDD
*/
uint64_t sylvan_nodecount_do_1(BDD a)
{
if (sylvan_isconst(a)) return 0;
bddnode_t na = GETNODE(a);
if (bddnode_getmark(na)) return 0;
bddnode_setmark(na, 1);
uint64_t result = 1;
result += sylvan_nodecount_do_1(bddnode_getlow(na));
result += sylvan_nodecount_do_1(bddnode_gethigh(na));
return result;
}
void sylvan_nodecount_do_2(BDD a)
{
if (sylvan_isconst(a)) return;
bddnode_t na = GETNODE(a);
if (!bddnode_getmark(na)) return;
bddnode_setmark(na, 0);
sylvan_nodecount_do_2(bddnode_getlow(na));
sylvan_nodecount_do_2(bddnode_gethigh(na));
}
size_t sylvan_nodecount(BDD a)
{
uint32_t result = sylvan_nodecount_do_1(a);
sylvan_nodecount_do_2(a);
return result;
}
/**
* Calculate the number of distinct paths to True.
*/
TASK_IMPL_2(double, sylvan_pathcount, BDD, bdd, BDDVAR, prev_level)
{
/* Trivial cases */
if (bdd == sylvan_false) return 0.0;
if (bdd == sylvan_true) return 1.0;
/* Perhaps execute garbage collection */
sylvan_gc_test();
sylvan_stats_count(BDD_PATHCOUNT);
BDD level = sylvan_var(bdd);
/* Consult cache */
int cachenow = granularity < 2 || prev_level == 0 ? 1 : prev_level / granularity != level / granularity;
if (cachenow) {
double result;
if (cache_get3(CACHE_BDD_PATHCOUNT, bdd, 0, 0, (uint64_t*)&result)) {
sylvan_stats_count(BDD_PATHCOUNT_CACHED);
return result;
}
}
SPAWN(sylvan_pathcount, sylvan_low(bdd), level);
SPAWN(sylvan_pathcount, sylvan_high(bdd), level);
double res1 = SYNC(sylvan_pathcount);
res1 += SYNC(sylvan_pathcount);
if (cachenow) {
if (cache_put3(CACHE_BDD_PATHCOUNT, bdd, 0, 0, *(uint64_t*)&res1)) sylvan_stats_count(BDD_PATHCOUNT_CACHEDPUT);
}
return res1;
}
/**
* Calculate the number of satisfying variable assignments according to <variables>.
*/
TASK_IMPL_3(double, sylvan_satcount, BDD, bdd, BDDSET, variables, BDDVAR, prev_level)
{
/* Trivial cases */
if (bdd == sylvan_false) return 0.0;
if (bdd == sylvan_true) return powl(2.0L, sylvan_set_count(variables));
/* Perhaps execute garbage collection */
sylvan_gc_test();
sylvan_stats_count(BDD_SATCOUNT);
/* Count variables before var(bdd) */
size_t skipped = 0;
BDDVAR var = sylvan_var(bdd);
bddnode_t set_node = GETNODE(variables);
BDDVAR set_var = bddnode_getvariable(set_node);
while (var != set_var) {
skipped++;
variables = node_high(variables, set_node);
// if this assertion fails, then variables is not the support of <bdd>
assert(!sylvan_set_isempty(variables));
set_node = GETNODE(variables);
set_var = bddnode_getvariable(set_node);
}
union {
double d;
uint64_t s;
} hack;
/* Consult cache */
int cachenow = granularity < 2 || prev_level == 0 ? 1 : prev_level / granularity != var / granularity;
if (cachenow) {
if (cache_get3(CACHE_BDD_SATCOUNT, bdd, variables, 0, &hack.s)) {
sylvan_stats_count(BDD_SATCOUNT_CACHED);
return hack.d * powl(2.0L, skipped);
}
}
SPAWN(sylvan_satcount, sylvan_high(bdd), node_high(variables, set_node), var);
double low = CALL(sylvan_satcount, sylvan_low(bdd), node_high(variables, set_node), var);
double result = low + SYNC(sylvan_satcount);
if (cachenow) {
hack.d = result;
if (cache_put3(CACHE_BDD_SATCOUNT, bdd, variables, 0, hack.s)) sylvan_stats_count(BDD_SATCOUNT_CACHEDPUT);
}
return result * powl(2.0L, skipped);
}
int
sylvan_sat_one(BDD bdd, BDDSET vars, uint8_t *str)
{
if (bdd == sylvan_false) return 0;
if (str == NULL) return 0;
if (sylvan_set_isempty(vars)) return 1;
for (;;) {
bddnode_t n_vars = GETNODE(vars);
if (bdd == sylvan_true) {
*str = 0;
} else {
bddnode_t n_bdd = GETNODE(bdd);
if (bddnode_getvariable(n_bdd) != bddnode_getvariable(n_vars)) {
*str = 0;
} else {
if (node_low(bdd, n_bdd) == sylvan_false) {
// take high edge
*str = 1;
bdd = node_high(bdd, n_bdd);
} else {
// take low edge
*str = 0;
bdd = node_low(bdd, n_bdd);
}
}
}
vars = node_high(vars, n_vars);
if (sylvan_set_isempty(vars)) break;
str++;
}
return 1;
}
BDD
sylvan_sat_one_bdd(BDD bdd)
{
if (bdd == sylvan_false) return sylvan_false;
if (bdd == sylvan_true) return sylvan_true;
bddnode_t node = GETNODE(bdd);
BDD low = node_low(bdd, node);
BDD high = node_high(bdd, node);
BDD m;
BDD result;
if (low == sylvan_false) {
m = sylvan_sat_one_bdd(high);
result = sylvan_makenode(bddnode_getvariable(node), sylvan_false, m);
} else if (high == sylvan_false) {
m = sylvan_sat_one_bdd(low);
result = sylvan_makenode(bddnode_getvariable(node), m, sylvan_false);
} else {
if (rand() & 0x2000) {
m = sylvan_sat_one_bdd(low);
result = sylvan_makenode(bddnode_getvariable(node), m, sylvan_false);
} else {
m = sylvan_sat_one_bdd(high);
result = sylvan_makenode(bddnode_getvariable(node), sylvan_false, m);
}
}
return result;
}
BDD
sylvan_cube(BDDSET vars, uint8_t *cube)
{
if (sylvan_set_isempty(vars)) return sylvan_true;
bddnode_t n = GETNODE(vars);
BDDVAR v = bddnode_getvariable(n);
vars = node_high(vars, n);
BDD result = sylvan_cube(vars, cube+1);
if (*cube == 0) {
result = sylvan_makenode(v, result, sylvan_false);
} else if (*cube == 1) {
result = sylvan_makenode(v, sylvan_false, result);
}
return result;
}
TASK_IMPL_3(BDD, sylvan_union_cube, BDD, bdd, BDDSET, vars, uint8_t *, cube)
{
/* Terminal cases */
if (bdd == sylvan_true) return sylvan_true;
if (bdd == sylvan_false) return sylvan_cube(vars, cube);
if (sylvan_set_isempty(vars)) return sylvan_true;
bddnode_t nv = GETNODE(vars);
for (;;) {
if (*cube == 0 || *cube == 1) break;
// *cube should be 2
cube++;
vars = node_high(vars, nv);
if (sylvan_set_isempty(vars)) return sylvan_true;
nv = GETNODE(vars);
}
sylvan_gc_test();
// missing: SV_CNT_OP
bddnode_t n = GETNODE(bdd);
BDD result = bdd;
BDDVAR v = bddnode_getvariable(nv);
BDDVAR n_level = bddnode_getvariable(n);
if (v < n_level) {
vars = node_high(vars, nv);
if (*cube == 0) {
result = sylvan_union_cube(bdd, vars, cube+1);
result = sylvan_makenode(v, result, bdd);
} else /* *cube == 1 */ {
result = sylvan_union_cube(bdd, vars, cube+1);
result = sylvan_makenode(v, bdd, result);
}
} else if (v > n_level) {
BDD high = node_high(bdd, n);
BDD low = node_low(bdd, n);
SPAWN(sylvan_union_cube, high, vars, cube);
BDD new_low = sylvan_union_cube(low, vars, cube);
bdd_refs_push(new_low);
BDD new_high = SYNC(sylvan_union_cube);
bdd_refs_pop(1);
if (new_low != low || new_high != high) {
result = sylvan_makenode(n_level, new_low, new_high);
}
} else /* v == n_level */ {
vars = node_high(vars, nv);
BDD high = node_high(bdd, n);
BDD low = node_low(bdd, n);
if (*cube == 0) {
BDD new_low = sylvan_union_cube(low, vars, cube+1);
if (new_low != low) {
result = sylvan_makenode(n_level, new_low, high);
}
} else /* *cube == 1 */ {
BDD new_high = sylvan_union_cube(high, vars, cube+1);
if (new_high != high) {
result = sylvan_makenode(n_level, low, new_high);
}
}
}
return result;
}
struct bdd_path
{
struct bdd_path *prev;
BDDVAR var;
int8_t val; // 0=false, 1=true, 2=both
};
VOID_TASK_5(sylvan_enum_do, BDD, bdd, BDDSET, vars, enum_cb, cb, void*, context, struct bdd_path*, path)
{
if (bdd == sylvan_false) return;
if (sylvan_set_isempty(vars)) {
/* bdd should now be true */
assert(bdd == sylvan_true);
/* compute length of path */
int i=0;
struct bdd_path *pp;
for (pp = path; pp != NULL; pp = pp->prev) i++;
/* if length is 0 (enum called with empty vars??), return */
if (i == 0) return;
/* fill cube and vars with trace */
uint8_t cube[i];
BDDVAR vars[i];
int j=0;
for (pp = path; pp != NULL; pp = pp->prev) {
cube[i-j-1] = pp->val;
vars[i-j-1] = pp->var;
j++;
}
/* call callback */
WRAP(cb, context, vars, cube, i);
return;
}
BDDVAR var = sylvan_var(vars);
vars = sylvan_set_next(vars);
BDDVAR bdd_var = sylvan_var(bdd);
/* assert var <= bdd_var */
if (bdd == sylvan_true || var < bdd_var) {
struct bdd_path pp0 = (struct bdd_path){path, var, 0};
CALL(sylvan_enum_do, bdd, vars, cb, context, &pp0);
struct bdd_path pp1 = (struct bdd_path){path, var, 1};
CALL(sylvan_enum_do, bdd, vars, cb, context, &pp1);
} else if (var == bdd_var) {
struct bdd_path pp0 = (struct bdd_path){path, var, 0};
CALL(sylvan_enum_do, sylvan_low(bdd), vars, cb, context, &pp0);
struct bdd_path pp1 = (struct bdd_path){path, var, 1};
CALL(sylvan_enum_do, sylvan_high(bdd), vars, cb, context, &pp1);
} else {
printf("var %u not expected (expecting %u)!\n", bdd_var, var);
assert(var <= bdd_var);
}
}
VOID_TASK_5(sylvan_enum_par_do, BDD, bdd, BDDSET, vars, enum_cb, cb, void*, context, struct bdd_path*, path)
{
if (bdd == sylvan_false) return;
if (sylvan_set_isempty(vars)) {
/* bdd should now be true */
assert(bdd == sylvan_true);
/* compute length of path */
int i=0;
struct bdd_path *pp;
for (pp = path; pp != NULL; pp = pp->prev) i++;
/* if length is 0 (enum called with empty vars??), return */
if (i == 0) return;
/* fill cube and vars with trace */
uint8_t cube[i];
BDDVAR vars[i];
int j=0;
for (pp = path; pp != NULL; pp = pp->prev) {
cube[i-j-1] = pp->val;
vars[i-j-1] = pp->var;
j++;
}
/* call callback */
WRAP(cb, context, vars, cube, i);
return;
}
BDD var = sylvan_var(vars);
vars = sylvan_set_next(vars);
BDD bdd_var = sylvan_var(bdd);
/* assert var <= bdd_var */
if (var < bdd_var) {
struct bdd_path pp1 = (struct bdd_path){path, var, 1};
SPAWN(sylvan_enum_par_do, bdd, vars, cb, context, &pp1);
struct bdd_path pp0 = (struct bdd_path){path, var, 0};
CALL(sylvan_enum_par_do, bdd, vars, cb, context, &pp0);
SYNC(sylvan_enum_par_do);
} else if (var == bdd_var) {
struct bdd_path pp1 = (struct bdd_path){path, var, 1};
SPAWN(sylvan_enum_par_do, sylvan_high(bdd), vars, cb, context, &pp1);
struct bdd_path pp0 = (struct bdd_path){path, var, 0};
CALL(sylvan_enum_par_do, sylvan_low(bdd), vars, cb, context, &pp0);
SYNC(sylvan_enum_par_do);
} else {
assert(var <= bdd_var);
}
}
VOID_TASK_IMPL_4(sylvan_enum, BDD, bdd, BDDSET, vars, enum_cb, cb, void*, context)
{
CALL(sylvan_enum_do, bdd, vars, cb, context, 0);
}
VOID_TASK_IMPL_4(sylvan_enum_par, BDD, bdd, BDDSET, vars, enum_cb, cb, void*, context)
{
CALL(sylvan_enum_par_do, bdd, vars, cb, context, 0);
}
TASK_5(BDD, sylvan_collect_do, BDD, bdd, BDDSET, vars, sylvan_collect_cb, cb, void*, context, struct bdd_path*, path)
{
if (bdd == sylvan_false) return sylvan_false;
if (sylvan_set_isempty(vars)) {
/* compute length of path */
int i=0;
struct bdd_path *pp;
for (pp = path; pp != NULL; pp = pp->prev) i++;
/* if length is 0 (enum called with empty vars??), return */
if (i == 0) return WRAP(cb, context, NULL);
/* fill cube and vars with trace */
uint8_t cube[i];
int j=0;
for (pp = path; pp != NULL; pp = pp->prev) {
cube[i-j-1] = pp->val;
j++;
}
/* call callback */
return WRAP(cb, context, cube);
} else {
BDD var = sylvan_var(vars);
vars = sylvan_set_next(vars);
BDD bdd_var = sylvan_var(bdd);
/* if fails, then <bdd> has variables not in <vars> */
assert(var <= bdd_var);
struct bdd_path pp1 = (struct bdd_path){path, var, 1};
struct bdd_path pp0 = (struct bdd_path){path, var, 0};
if (var < bdd_var) {
bdd_refs_spawn(SPAWN(sylvan_collect_do, bdd, vars, cb, context, &pp1));
BDD low = bdd_refs_push(CALL(sylvan_collect_do, bdd, vars, cb, context, &pp0));
BDD high = bdd_refs_push(bdd_refs_sync(SYNC(sylvan_collect_do)));
BDD res = sylvan_or(low, high);
bdd_refs_pop(2);
return res;
} else if (var == bdd_var) {
bdd_refs_spawn(SPAWN(sylvan_collect_do, sylvan_high(bdd), vars, cb, context, &pp1));
BDD low = bdd_refs_push(CALL(sylvan_collect_do, sylvan_low(bdd), vars, cb, context, &pp0));
BDD high = bdd_refs_push(bdd_refs_sync(SYNC(sylvan_collect_do)));
BDD res = sylvan_or(low, high);
bdd_refs_pop(2);
return res;
} else {
return sylvan_invalid; // unreachable
}
}
}
TASK_IMPL_4(BDD, sylvan_collect, BDD, bdd, BDDSET, vars, sylvan_collect_cb, cb, void*, context)
{
return CALL(sylvan_collect_do, bdd, vars, cb, context, 0);
}
/**
* IMPLEMENTATION OF BDDSET
*/
int
sylvan_set_in(BDDSET set, BDDVAR level)
{
while (!sylvan_set_isempty(set)) {
bddnode_t n = GETNODE(set);
BDDVAR n_level = bddnode_getvariable(n);
if (n_level == level) return 1;
if (n_level > level) return 0; // BDDs are ordered
set = node_high(set, n);
}
return 0;
}
size_t
sylvan_set_count(BDDSET set)
{
size_t result = 0;
for (;!sylvan_set_isempty(set);set = sylvan_set_next(set)) result++;
return result;
}
void
sylvan_set_toarray(BDDSET set, BDDVAR *arr)
{
size_t i = 0;
while (!sylvan_set_isempty(set)) {
bddnode_t n = GETNODE(set);
arr[i++] = bddnode_getvariable(n);
set = node_high(set, n);
}
}
TASK_IMPL_2(BDDSET, sylvan_set_fromarray, BDDVAR*, arr, size_t, length)
{
if (length == 0) return sylvan_set_empty();
BDDSET sub = sylvan_set_fromarray(arr+1, length-1);
bdd_refs_push(sub);
BDDSET result = sylvan_set_add(sub, *arr);
bdd_refs_pop(1);
return result;
}
void
sylvan_test_isset(BDDSET set)
{
while (set != sylvan_false) {
assert(set != sylvan_true);
assert(llmsset_is_marked(nodes, set));
bddnode_t n = GETNODE(set);
assert(node_low(set, n) == sylvan_true);
set = node_high(set, n);
}
}
/**
* IMPLEMENTATION OF BDDMAP
*/
BDDMAP
sylvan_map_add(BDDMAP map, BDDVAR key, BDD value)
{
if (sylvan_map_isempty(map)) return sylvan_makenode(key, sylvan_map_empty(), value);
bddnode_t n = GETNODE(map);
BDDVAR key_m = bddnode_getvariable(n);
if (key_m < key) {
// add recursively and rebuild tree
BDDMAP low = sylvan_map_add(node_low(map, n), key, value);
BDDMAP result = sylvan_makenode(key_m, low, node_high(map, n));
return result;
} else if (key_m > key) {
return sylvan_makenode(key, map, value);
} else {
// replace old
return sylvan_makenode(key, node_low(map, n), value);
}
}
BDDMAP
sylvan_map_addall(BDDMAP map_1, BDDMAP map_2)
{
// one of the maps is empty
if (sylvan_map_isempty(map_1)) return map_2;
if (sylvan_map_isempty(map_2)) return map_1;
bddnode_t n_1 = GETNODE(map_1);
BDDVAR key_1 = bddnode_getvariable(n_1);
bddnode_t n_2 = GETNODE(map_2);
BDDVAR key_2 = bddnode_getvariable(n_2);
BDDMAP result;
if (key_1 < key_2) {
// key_1, recurse on n_1->low, map_2
BDDMAP low = sylvan_map_addall(node_low(map_1, n_1), map_2);
result = sylvan_makenode(key_1, low, node_high(map_1, n_1));
} else if (key_1 > key_2) {
// key_2, recurse on map_1, n_2->low
BDDMAP low = sylvan_map_addall(map_1, node_low(map_2, n_2));
result = sylvan_makenode(key_2, low, node_high(map_2, n_2));
} else {
// equal: key_2, recurse on n_1->low, n_2->low
BDDMAP low = sylvan_map_addall(node_low(map_1, n_1), node_low(map_2, n_2));
result = sylvan_makenode(key_2, low, node_high(map_2, n_2));
}
return result;
}
BDDMAP
sylvan_map_remove(BDDMAP map, BDDVAR key)
{
if (sylvan_map_isempty(map)) return map;
bddnode_t n = GETNODE(map);
BDDVAR key_m = bddnode_getvariable(n);
if (key_m < key) {
BDDMAP low = sylvan_map_remove(node_low(map, n), key);
BDDMAP result = sylvan_makenode(key_m, low, node_high(map, n));
return result;
} else if (key_m > key) {
return map;
} else {
return node_low(map, n);
}
}
BDDMAP
sylvan_map_removeall(BDDMAP map, BDDSET toremove)
{
if (sylvan_map_isempty(map)) return map;
if (sylvan_set_isempty(toremove)) return map;
bddnode_t n_1 = GETNODE(map);
BDDVAR key_1 = bddnode_getvariable(n_1);
bddnode_t n_2 = GETNODE(toremove);
BDDVAR key_2 = bddnode_getvariable(n_2);
if (key_1 < key_2) {
BDDMAP low = sylvan_map_removeall(node_low(map, n_1), toremove);
BDDMAP result = sylvan_makenode(key_1, low, node_high(map, n_1));
return result;
} else if (key_1 > key_2) {
return sylvan_map_removeall(map, node_high(toremove, n_2));
} else {
return sylvan_map_removeall(node_low(map, n_1), node_high(toremove, n_2));
}
}
int
sylvan_map_in(BDDMAP map, BDDVAR key)
{
while (!sylvan_map_isempty(map)) {
bddnode_t n = GETNODE(map);
BDDVAR n_level = bddnode_getvariable(n);
if (n_level == key) return 1;
if (n_level > key) return 0; // BDDs are ordered
map = node_low(map, n);
}
return 0;
}
size_t
sylvan_map_count(BDDMAP map)
{
size_t r=0;
while (!sylvan_map_isempty(map)) { r++; map=sylvan_map_next(map); }
return r;
}
BDDMAP
sylvan_set_to_map(BDDSET set, BDD value)
{
if (sylvan_set_isempty(set)) return sylvan_map_empty();
bddnode_t set_n = GETNODE(set);
BDD sub = sylvan_set_to_map(node_high(set, set_n), value);
BDD result = sylvan_makenode(sub, bddnode_getvariable(set_n), value);
return result;
}
/**
* Determine the support of a BDD (all variables used in the BDD)
*/
TASK_IMPL_1(BDD, sylvan_support, BDD, bdd)
{
if (bdd == sylvan_true || bdd == sylvan_false) return sylvan_set_empty(); // return empty set
sylvan_gc_test();
sylvan_stats_count(BDD_SUPPORT);
BDD result;
if (cache_get3(CACHE_BDD_SUPPORT, bdd, 0, 0, &result)) {
sylvan_stats_count(BDD_SUPPORT_CACHED);
return result;
}
bddnode_t n = GETNODE(bdd);
BDD high, low, set;
/* compute recursively */
bdd_refs_spawn(SPAWN(sylvan_support, bddnode_getlow(n)));
high = bdd_refs_push(CALL(sylvan_support, bddnode_gethigh(n)));
low = bdd_refs_push(bdd_refs_sync(SYNC(sylvan_support)));
/* take intersection of support of low and support of high */
set = sylvan_and(low, high);
bdd_refs_pop(2);
/* add current level to set */
result = sylvan_makenode(bddnode_getvariable(n), sylvan_false, set);
if (cache_put3(CACHE_BDD_SUPPORT, bdd, 0, 0, result)) sylvan_stats_count(BDD_SUPPORT_CACHEDPUT);
return result;
}
static void
sylvan_unmark_rec(bddnode_t node)
{
if (bddnode_getmark(node)) {
bddnode_setmark(node, 0);
if (!sylvan_isconst(bddnode_getlow(node))) sylvan_unmark_rec(GETNODE(bddnode_getlow(node)));
if (!sylvan_isconst(bddnode_gethigh(node))) sylvan_unmark_rec(GETNODE(bddnode_gethigh(node)));
}
}
/**
* fprint, print
*/
void
sylvan_fprint(FILE *f, BDD bdd)
{
sylvan_serialize_reset();
size_t v = sylvan_serialize_add(bdd);
fprintf(f, "%s%zu,", bdd&sylvan_complement?"!":"", v);
sylvan_serialize_totext(f);
}
void
sylvan_print(BDD bdd)
{
sylvan_fprint(stdout, bdd);
}
/**
* Output to .DOT files
*/
/***
* We keep a set [level -> [node]] using AVLset
*/
struct level_to_nodeset {
BDDVAR level;
avl_node_t *set;
};
AVL(level_to_nodeset, struct level_to_nodeset)
{
if (left->level > right->level) return 1;
if (right->level > left->level) return -1;
return 0;
}
AVL(nodeset, BDD)
{
if (*left > *right) return 1;
if (*right > *left) return -1;
return 0;
}
/* returns 1 if inserted, 0 if already existed */
static int __attribute__((noinline))
sylvan_dothelper_register(avl_node_t **set, BDD bdd)
{
struct level_to_nodeset s, *ss;
s.level = sylvan_var(bdd);
ss = level_to_nodeset_search(*set, &s);
if (ss == NULL) {
s.set = NULL;
ss = level_to_nodeset_put(set, &s, NULL);
}
assert(ss != NULL);
return nodeset_insert(&ss->set, &bdd);
}
static void
sylvan_fprintdot_rec(FILE *out, BDD bdd, avl_node_t **levels)
{
bdd = BDD_STRIPMARK(bdd);
if (bdd == sylvan_false) return;
if (!sylvan_dothelper_register(levels, bdd)) return;
BDD low = sylvan_low(bdd);
BDD high = sylvan_high(bdd);
fprintf(out, "\"%" PRIx64 "\" [label=\"%d\"];\n", bdd, sylvan_var(bdd));
fprintf(out, "\"%" PRIx64 "\" -> \"%" PRIx64 "\" [style=dashed];\n", bdd, low);
fprintf(out, "\"%" PRIx64 "\" -> \"%" PRIx64 "\" [style=solid dir=both arrowtail=%s];\n", bdd, BDD_STRIPMARK(high), BDD_HASMARK(high) ? "dot" : "none");
sylvan_fprintdot_rec(out, low, levels);
sylvan_fprintdot_rec(out, high, levels);
}
void
sylvan_fprintdot(FILE *out, BDD bdd)
{
fprintf(out, "digraph \"DD\" {\n");
fprintf(out, "graph [dpi = 300];\n");
fprintf(out, "center = true;\n");
fprintf(out, "edge [dir = forward];\n");
fprintf(out, "0 [label=\"0\", style=filled, shape=box, height=0.3, width=0.3];\n");
fprintf(out, "root [style=invis];\n");
fprintf(out, "root -> \"%" PRIx64 "\" [style=solid dir=both arrowtail=%s];\n", BDD_STRIPMARK(bdd), BDD_HASMARK(bdd) ? "dot" : "none");
avl_node_t *levels = NULL;
sylvan_fprintdot_rec(out, bdd, &levels);
if (levels != NULL) {
size_t levels_count = avl_count(levels);
struct level_to_nodeset *arr = level_to_nodeset_toarray(levels);
size_t i;
for (i=0;i<levels_count;i++) {
fprintf(out, "{ rank=same; ");
size_t node_count = avl_count(arr[i].set);
size_t j;
BDD *arr_j = nodeset_toarray(arr[i].set);
for (j=0;j<node_count;j++) {
fprintf(out, "\"%" PRIx64 "\"; ", arr_j[j]);
}
fprintf(out, "}\n");
}
level_to_nodeset_free(&levels);
}
fprintf(out, "}\n");
}
void
sylvan_printdot(BDD bdd)
{
sylvan_fprintdot(stdout, bdd);
}
static void
sylvan_fprintdot_nc_rec(FILE *out, BDD bdd, avl_node_t **levels)
{
if (bdd == sylvan_true || bdd == sylvan_false) return;
if (!sylvan_dothelper_register(levels, bdd)) return;
BDD low = sylvan_low(bdd);
BDD high = sylvan_high(bdd);
fprintf(out, "\"%" PRIx64 "\" [label=\"%d\"];\n", bdd, sylvan_var(bdd));
fprintf(out, "\"%" PRIx64 "\" -> \"%" PRIx64 "\" [style=dashed];\n", bdd, low);
fprintf(out, "\"%" PRIx64 "\" -> \"%" PRIx64 "\" [style=solid];\n", bdd, high);
sylvan_fprintdot_nc_rec(out, low, levels);
sylvan_fprintdot_nc_rec(out, high, levels);
}
void
sylvan_fprintdot_nc(FILE *out, BDD bdd)
{
fprintf(out, "digraph \"DD\" {\n");
fprintf(out, "graph [dpi = 300];\n");
fprintf(out, "center = true;\n");
fprintf(out, "edge [dir = forward];\n");
fprintf(out, "\"%" PRIx64 "\" [shape=box, label=\"F\", style=filled, shape=box, height=0.3, width=0.3];\n", sylvan_false);
fprintf(out, "\"%" PRIx64 "\" [shape=box, label=\"T\", style=filled, shape=box, height=0.3, width=0.3];\n", sylvan_true);
fprintf(out, "root [style=invis];\n");
fprintf(out, "root -> \"%" PRIx64 "\" [style=solid];\n", bdd);
avl_node_t *levels = NULL;
sylvan_fprintdot_nc_rec(out, bdd, &levels);
if (levels != NULL) {
size_t levels_count = avl_count(levels);
struct level_to_nodeset *arr = level_to_nodeset_toarray(levels);
size_t i;
for (i=0;i<levels_count;i++) {
fprintf(out, "{ rank=same; ");
size_t node_count = avl_count(arr[i].set);
size_t j;
BDD *arr_j = nodeset_toarray(arr[i].set);
for (j=0;j<node_count;j++) {
fprintf(out, "\"%" PRIx64 "\"; ", arr_j[j]);
}
fprintf(out, "}\n");
}
level_to_nodeset_free(&levels);
}
fprintf(out, "}\n");
}
void
sylvan_printdot_nc(BDD bdd)
{
sylvan_fprintdot_nc(stdout, bdd);
}
/**
* SERIALIZATION
*/
struct sylvan_ser {
BDD bdd;
size_t assigned;
};
// Define a AVL tree type with prefix 'sylvan_ser' holding
// nodes of struct sylvan_ser with the following compare() function...
AVL(sylvan_ser, struct sylvan_ser)
{
if (left->bdd > right->bdd) return 1;
if (left->bdd < right->bdd) return -1;
return 0;
}
// Define a AVL tree type with prefix 'sylvan_ser_reversed' holding
// nodes of struct sylvan_ser with the following compare() function...
AVL(sylvan_ser_reversed, struct sylvan_ser)
{
if (left->assigned > right->assigned) return 1;
if (left->assigned < right->assigned) return -1;
return 0;
}
// Initially, both sets are empty
static avl_node_t *sylvan_ser_set = NULL;
static avl_node_t *sylvan_ser_reversed_set = NULL;
// Start counting (assigning numbers to BDDs) at 1
static size_t sylvan_ser_counter = 1;
static size_t sylvan_ser_done = 0;
// Given a BDD, assign unique numbers to all nodes
static size_t
sylvan_serialize_assign_rec(BDD bdd)
{
if (sylvan_isnode(bdd)) {
bddnode_t n = GETNODE(bdd);
struct sylvan_ser s, *ss;
s.bdd = BDD_STRIPMARK(bdd);
ss = sylvan_ser_search(sylvan_ser_set, &s);
if (ss == NULL) {
// assign dummy value
s.assigned = 0;
ss = sylvan_ser_put(&sylvan_ser_set, &s, NULL);
// first assign recursively
sylvan_serialize_assign_rec(bddnode_getlow(n));
sylvan_serialize_assign_rec(bddnode_gethigh(n));
// assign real value
ss->assigned = sylvan_ser_counter++;
// put a copy in the reversed table
sylvan_ser_reversed_insert(&sylvan_ser_reversed_set, ss);
}
return ss->assigned;
}
return BDD_STRIPMARK(bdd);
}
size_t
sylvan_serialize_add(BDD bdd)
{
return BDD_TRANSFERMARK(bdd, sylvan_serialize_assign_rec(bdd));
}
void
sylvan_serialize_reset()
{
sylvan_ser_free(&sylvan_ser_set);
sylvan_ser_free(&sylvan_ser_reversed_set);
sylvan_ser_counter = 1;
sylvan_ser_done = 0;
}
size_t
sylvan_serialize_get(BDD bdd)
{
if (!sylvan_isnode(bdd)) return bdd;
struct sylvan_ser s, *ss;
s.bdd = BDD_STRIPMARK(bdd);
ss = sylvan_ser_search(sylvan_ser_set, &s);
assert(ss != NULL);
return BDD_TRANSFERMARK(bdd, ss->assigned);
}
BDD
sylvan_serialize_get_reversed(size_t value)
{
if (!sylvan_isnode(value)) return value;
struct sylvan_ser s, *ss;
s.assigned = BDD_STRIPMARK(value);
ss = sylvan_ser_reversed_search(sylvan_ser_reversed_set, &s);
assert(ss != NULL);
return BDD_TRANSFERMARK(value, ss->bdd);
}
void
sylvan_serialize_totext(FILE *out)
{
fprintf(out, "[");
avl_iter_t *it = sylvan_ser_reversed_iter(sylvan_ser_reversed_set);
struct sylvan_ser *s;
while ((s=sylvan_ser_reversed_iter_next(it))) {
BDD bdd = s->bdd;
bddnode_t n = GETNODE(bdd);
fprintf(out, "(%zu,%u,%zu,%zu,%u),", s->assigned,
bddnode_getvariable(n),
(size_t)bddnode_getlow(n),
(size_t)BDD_STRIPMARK(bddnode_gethigh(n)),
BDD_HASMARK(bddnode_gethigh(n)) ? 1 : 0);
}
sylvan_ser_reversed_iter_free(it);
fprintf(out, "]");
}
void
sylvan_serialize_tofile(FILE *out)
{
size_t count = avl_count(sylvan_ser_reversed_set);
assert(count >= sylvan_ser_done);
assert(count == sylvan_ser_counter-1);
count -= sylvan_ser_done;
fwrite(&count, sizeof(size_t), 1, out);
struct sylvan_ser *s;
avl_iter_t *it = sylvan_ser_reversed_iter(sylvan_ser_reversed_set);
/* Skip already written entries */
size_t index = 0;
while (index < sylvan_ser_done && (s=sylvan_ser_reversed_iter_next(it))) {
index++;
assert(s->assigned == index);
}
while ((s=sylvan_ser_reversed_iter_next(it))) {
index++;
assert(s->assigned == index);
bddnode_t n = GETNODE(s->bdd);
struct bddnode node;
bddnode_makenode(&node, bddnode_getvariable(n), sylvan_serialize_get(bddnode_getlow(n)), sylvan_serialize_get(bddnode_gethigh(n)));
fwrite(&node, sizeof(struct bddnode), 1, out);
}
sylvan_ser_done = sylvan_ser_counter-1;
sylvan_ser_reversed_iter_free(it);
}
void
sylvan_serialize_fromfile(FILE *in)
{
size_t count, i;
if (fread(&count, sizeof(size_t), 1, in) != 1) {
// TODO FIXME return error
printf("sylvan_serialize_fromfile: file format error, giving up\n");
exit(-1);
}
for (i=1; i<=count; i++) {
struct bddnode node;
if (fread(&node, sizeof(struct bddnode), 1, in) != 1) {
// TODO FIXME return error
printf("sylvan_serialize_fromfile: file format error, giving up\n");
exit(-1);
}
BDD low = sylvan_serialize_get_reversed(bddnode_getlow(&node));
BDD high = sylvan_serialize_get_reversed(bddnode_gethigh(&node));
struct sylvan_ser s;
s.bdd = sylvan_makenode(bddnode_getvariable(&node), low, high);
s.assigned = ++sylvan_ser_done; // starts at 0 but we want 1-based...
sylvan_ser_insert(&sylvan_ser_set, &s);
sylvan_ser_reversed_insert(&sylvan_ser_reversed_set, &s);
}
}
/**
* Generate SHA2 structural hashes.
* Hashes are independent of location.
* Mainly useful for debugging purposes.
*/
static void
sylvan_sha2_rec(BDD bdd, SHA256_CTX *ctx)
{
if (bdd == sylvan_true || bdd == sylvan_false) {
SHA256_Update(ctx, (void*)&bdd, sizeof(BDD));
return;
}
bddnode_t node = GETNODE(bdd);
if (bddnode_getmark(node) == 0) {
bddnode_setmark(node, 1);
uint32_t level = bddnode_getvariable(node);
if (BDD_STRIPMARK(bddnode_gethigh(node))) level |= 0x80000000;
SHA256_Update(ctx, (void*)&level, sizeof(uint32_t));
sylvan_sha2_rec(bddnode_gethigh(node), ctx);
sylvan_sha2_rec(bddnode_getlow(node), ctx);
}
}
void
sylvan_printsha(BDD bdd)
{
sylvan_fprintsha(stdout, bdd);
}
void
sylvan_fprintsha(FILE *f, BDD bdd)
{
char buf[80];
sylvan_getsha(bdd, buf);
fprintf(f, "%s", buf);
}
void
sylvan_getsha(BDD bdd, char *target)
{
SHA256_CTX ctx;
SHA256_Init(&ctx);
sylvan_sha2_rec(bdd, &ctx);
if (bdd != sylvan_true && bdd != sylvan_false) sylvan_unmark_rec(GETNODE(bdd));
SHA256_End(&ctx, target);
}
/**
* Debug tool to check that a BDD is properly ordered.
* Also that every BDD node is marked 'in-use' in the hash table.
*/
TASK_2(int, sylvan_test_isbdd_rec, BDD, bdd, BDDVAR, parent_var)
{
if (bdd == sylvan_true || bdd == sylvan_false) return 1;
assert(llmsset_is_marked(nodes, BDD_STRIPMARK(bdd)));
sylvan_stats_count(BDD_ISBDD);
uint64_t result;
if (cache_get3(CACHE_BDD_ISBDD, bdd, 0, 0, &result)) {
sylvan_stats_count(BDD_ISBDD_CACHED);
return result;
}
bddnode_t n = GETNODE(bdd);
BDDVAR var = bddnode_getvariable(n);
if (var <= parent_var) {
result = 0;
} else {
SPAWN(sylvan_test_isbdd_rec, node_low(bdd, n), var);
result = (uint64_t)CALL(sylvan_test_isbdd_rec, node_high(bdd, n), var);
if (!SYNC(sylvan_test_isbdd_rec)) result = 0;
}
if (cache_put3(CACHE_BDD_ISBDD, bdd, 0, 0, result)) sylvan_stats_count(BDD_ISBDD_CACHEDPUT);
return result;
}
TASK_IMPL_1(int, sylvan_test_isbdd, BDD, bdd)
{
if (bdd == sylvan_true) return 1;
if (bdd == sylvan_false) return 1;
assert(llmsset_is_marked(nodes, BDD_STRIPMARK(bdd)));
bddnode_t n = GETNODE(bdd);
BDDVAR var = bddnode_getvariable(n);
SPAWN(sylvan_test_isbdd_rec, node_low(bdd, n), var);
int result = CALL(sylvan_test_isbdd_rec, node_high(bdd, n), var);
if (!SYNC(sylvan_test_isbdd_rec)) result = 0;
return result;
}