llvm-project/llvm/utils/Burg/trim.c

413 lines
9.2 KiB
C

char rcsid_trim[] = "$Id$";
#include <stdio.h>
#include "b.h"
#include "fe.h"
Relation *allpairs;
int trimflag = 0;
int debugTrim = 0;
static void siblings ARGS((int, int));
static void findAllNexts ARGS((void));
static Relation *newAllPairs ARGS((void));
static void
siblings(i, j) int i; int j;
{
int k;
List pl;
DeltaCost Max;
int foundmax;
allpairs[i][j].sibComputed = 1;
if (i == 1) {
return; /* never trim start symbol */
}
if (i==j) {
return;
}
ZEROCOST(Max);
foundmax = 0;
for (k = 1; k < max_nonterminal; k++) {
DeltaCost tmp;
if (k==i || k==j) {
continue;
}
if (!allpairs[k][i].rule) {
continue;
}
if (!allpairs[k][j].rule) {
return;
}
ASSIGNCOST(tmp, allpairs[k][j].chain);
MINUSCOST(tmp, allpairs[k][i].chain);
if (foundmax) {
if (LESSCOST(Max, tmp)) {
ASSIGNCOST(Max, tmp);
}
} else {
foundmax = 1;
ASSIGNCOST(Max, tmp);
}
}
for (pl = rules; pl; pl = pl->next) {
Rule p = (Rule) pl->x;
Operator op = p->pat->op;
List oprule;
DeltaCost Min;
int foundmin;
if (!op) {
continue;
}
switch (op->arity) {
case 0:
continue;
case 1:
if (!allpairs[p->pat->children[0]->num ][ i].rule) {
continue;
}
foundmin = 0;
for (oprule = op->table->rules; oprule; oprule = oprule->next) {
Rule s = (Rule) oprule->x;
DeltaPtr Cx;
DeltaPtr Csj;
DeltaPtr Cpi;
DeltaCost tmp;
if (!allpairs[p->lhs->num ][ s->lhs->num].rule
|| !allpairs[s->pat->children[0]->num ][ j].rule) {
continue;
}
Cx = allpairs[p->lhs->num ][ s->lhs->num].chain;
Csj= allpairs[s->pat->children[0]->num ][ j].chain;
Cpi= allpairs[p->pat->children[0]->num ][ i].chain;
ASSIGNCOST(tmp, Cx);
ADDCOST(tmp, s->delta);
ADDCOST(tmp, Csj);
MINUSCOST(tmp, Cpi);
MINUSCOST(tmp, p->delta);
if (foundmin) {
if (LESSCOST(tmp, Min)) {
ASSIGNCOST(Min, tmp);
}
} else {
foundmin = 1;
ASSIGNCOST(Min, tmp);
}
}
if (!foundmin) {
return;
}
if (foundmax) {
if (LESSCOST(Max, Min)) {
ASSIGNCOST(Max, Min);
}
} else {
foundmax = 1;
ASSIGNCOST(Max, Min);
}
break;
case 2:
/* do first dimension */
if (allpairs[p->pat->children[0]->num ][ i].rule) {
foundmin = 0;
for (oprule = op->table->rules; oprule; oprule = oprule->next) {
Rule s = (Rule) oprule->x;
DeltaPtr Cx;
DeltaPtr Cb;
DeltaPtr Csj;
DeltaPtr Cpi;
DeltaCost tmp;
if (allpairs[p->lhs->num ][ s->lhs->num].rule
&& allpairs[s->pat->children[0]->num ][ j].rule
&& allpairs[s->pat->children[1]->num ][ p->pat->children[1]->num].rule) {
Cx = allpairs[p->lhs->num ][ s->lhs->num].chain;
Csj= allpairs[s->pat->children[0]->num ][ j].chain;
Cpi= allpairs[p->pat->children[0]->num ][ i].chain;
Cb = allpairs[s->pat->children[1]->num ][ p->pat->children[1]->num].chain;
ASSIGNCOST(tmp, Cx);
ADDCOST(tmp, s->delta);
ADDCOST(tmp, Csj);
ADDCOST(tmp, Cb);
MINUSCOST(tmp, Cpi);
MINUSCOST(tmp, p->delta);
if (foundmin) {
if (LESSCOST(tmp, Min)) {
ASSIGNCOST(Min, tmp);
}
} else {
foundmin = 1;
ASSIGNCOST(Min, tmp);
}
}
}
if (!foundmin) {
return;
}
if (foundmax) {
if (LESSCOST(Max, Min)) {
ASSIGNCOST(Max, Min);
}
} else {
foundmax = 1;
ASSIGNCOST(Max, Min);
}
}
/* do second dimension */
if (allpairs[p->pat->children[1]->num ][ i].rule) {
foundmin = 0;
for (oprule = op->table->rules; oprule; oprule = oprule->next) {
Rule s = (Rule) oprule->x;
DeltaPtr Cx;
DeltaPtr Cb;
DeltaPtr Csj;
DeltaPtr Cpi;
DeltaCost tmp;
if (allpairs[p->lhs->num ][ s->lhs->num].rule
&& allpairs[s->pat->children[1]->num ][ j].rule
&& allpairs[s->pat->children[0]->num ][ p->pat->children[0]->num].rule) {
Cx = allpairs[p->lhs->num ][ s->lhs->num].chain;
Csj= allpairs[s->pat->children[1]->num ][ j].chain;
Cpi= allpairs[p->pat->children[1]->num ][ i].chain;
Cb = allpairs[s->pat->children[0]->num ][ p->pat->children[0]->num].chain;
ASSIGNCOST(tmp, Cx);
ADDCOST(tmp, s->delta);
ADDCOST(tmp, Csj);
ADDCOST(tmp, Cb);
MINUSCOST(tmp, Cpi);
MINUSCOST(tmp, p->delta);
if (foundmin) {
if (LESSCOST(tmp, Min)) {
ASSIGNCOST(Min, tmp);
}
} else {
foundmin = 1;
ASSIGNCOST(Min, tmp);
}
}
}
if (!foundmin) {
return;
}
if (foundmax) {
if (LESSCOST(Max, Min)) {
ASSIGNCOST(Max, Min);
}
} else {
foundmax = 1;
ASSIGNCOST(Max, Min);
}
}
break;
default:
assert(0);
}
}
allpairs[i ][ j].sibFlag = foundmax;
ASSIGNCOST(allpairs[i ][ j].sibling, Max);
}
static void
findAllNexts()
{
int i,j;
int last;
for (i = 1; i < max_nonterminal; i++) {
last = 0;
for (j = 1; j < max_nonterminal; j++) {
if (allpairs[i ][j].rule) {
allpairs[i ][ last].nextchain = j;
last = j;
}
}
}
/*
for (i = 1; i < max_nonterminal; i++) {
last = 0;
for (j = 1; j < max_nonterminal; j++) {
if (allpairs[i ][j].sibFlag) {
allpairs[i ][ last].nextsibling = j;
last = j;
}
}
}
*/
}
static Relation *
newAllPairs()
{
int i;
Relation *rv;
rv = (Relation*) zalloc(max_nonterminal * sizeof(Relation));
for (i = 0; i < max_nonterminal; i++) {
rv[i] = (Relation) zalloc(max_nonterminal * sizeof(struct relation));
}
return rv;
}
void
findAllPairs()
{
List pl;
int changes;
int j;
allpairs = newAllPairs();
for (pl = chainrules; pl; pl = pl->next) {
Rule p = (Rule) pl->x;
NonTerminalNum rhs = p->pat->children[0]->num;
NonTerminalNum lhs = p->lhs->num;
Relation r = &allpairs[lhs ][ rhs];
if (LESSCOST(p->delta, r->chain)) {
ASSIGNCOST(r->chain, p->delta);
r->rule = p;
}
}
for (j = 1; j < max_nonterminal; j++) {
Relation r = &allpairs[j ][ j];
ZEROCOST(r->chain);
r->rule = &stub_rule;
}
changes = 1;
while (changes) {
changes = 0;
for (pl = chainrules; pl; pl = pl->next) {
Rule p = (Rule) pl->x;
NonTerminalNum rhs = p->pat->children[0]->num;
NonTerminalNum lhs = p->lhs->num;
int i;
for (i = 1; i < max_nonterminal; i++) {
Relation r = &allpairs[rhs ][ i];
Relation s = &allpairs[lhs ][ i];
DeltaCost dc;
if (!r->rule) {
continue;
}
ASSIGNCOST(dc, p->delta);
ADDCOST(dc, r->chain);
if (!s->rule || LESSCOST(dc, s->chain)) {
s->rule = p;
ASSIGNCOST(s->chain, dc);
changes = 1;
}
}
}
}
findAllNexts();
}
void
trim(t) Item_Set t;
{
int m,n;
static short *vec = 0;
int last;
assert(!t->closed);
debug(debugTrim, printf("Begin Trim\n"));
debug(debugTrim, dumpItem_Set(t));
last = 0;
if (!vec) {
vec = (short*) zalloc(max_nonterminal * sizeof(*vec));
}
for (m = 1; m < max_nonterminal; m++) {
if (t->virgin[m].rule) {
vec[last++] = m;
}
}
for (m = 0; m < last; m++) {
DeltaCost tmp;
int j;
int i;
i = vec[m];
for (j = allpairs[i ][ 0].nextchain; j; j = allpairs[i ][ j].nextchain) {
if (i == j) {
continue;
}
if (!t->virgin[j].rule) {
continue;
}
ASSIGNCOST(tmp, t->virgin[j].delta);
ADDCOST(tmp, allpairs[i ][ j].chain);
if (!LESSCOST(t->virgin[i].delta, tmp)) {
t->virgin[i].rule = 0;
ZEROCOST(t->virgin[i].delta);
debug(debugTrim, printf("Trimmed Chain (%d,%d)\n", i,j));
goto outer;
}
}
if (!trimflag) {
continue;
}
for (n = 0; n < last; n++) {
j = vec[n];
if (i == j) {
continue;
}
if (!t->virgin[j].rule) {
continue;
}
if (!allpairs[i][j].sibComputed) {
siblings(i,j);
}
if (!allpairs[i][j].sibFlag) {
continue;
}
ASSIGNCOST(tmp, t->virgin[j].delta);
ADDCOST(tmp, allpairs[i ][ j].sibling);
if (!LESSCOST(t->virgin[i].delta, tmp)) {
t->virgin[i].rule = 0;
ZEROCOST(t->virgin[i].delta);
goto outer;
}
}
outer: ;
}
debug(debugTrim, dumpItem_Set(t));
debug(debugTrim, printf("End Trim\n"));
}
void
dumpRelation(r) Relation r;
{
printf("{ %d %ld %d %ld }", r->rule->erulenum, (long) r->chain, r->sibFlag, (long) r->sibling);
}
void
dumpAllPairs()
{
int i,j;
printf("Dumping AllPairs\n");
for (i = 1; i < max_nonterminal; i++) {
for (j = 1; j < max_nonterminal; j++) {
dumpRelation(&allpairs[i ][j]);
}
printf("\n");
}
}