/*
- freezeset - final processing on a set of characters
*
* The main task here is merging identical sets. This is usually a waste
* of time (although the hash code minimizes the overhead), but can win
* big if REG_ICASE is being used. REG_ICASE, by the way, is why the hash
* is done using addition rather than xor -- all ASCII [aA] sets xor to
* the same value!
*/
static int /* set number */
freezeset(struct parse *p, cset *cs)
{
uch h = cs->hash;
size_t i;
cset *top = &p->g->sets[p->g->ncsets];
cset *cs2;
size_t css = (size_t)p->g->csetsize;
/* look for an earlier one which is the same */
for (cs2 = &p->g->sets[0]; cs2 < top; cs2++)
if (cs2->hash == h && cs2 != cs) {
/* maybe */
for (i = 0; i < css; i++)
if (!!CHIN(cs2, i) != !!CHIN(cs, i))
break; /* no */
if (i == css)
break; /* yes */
}
if (cs2 < top) { /* found one */
freeset(p, cs);
cs = cs2;
}
return((int)(cs - p->g->sets));
}
void subsetconstruct(int (*dfatable)[128], struct set *acceptset)
{
struct dfa *dfa;
struct set *next;
int nextstate = 0;
int c, state;
struct accept *accept;
while (dfa = next_dfa()) {
for (c = 0; c < MAX_CHARS; c++) {
/* compute next dfa, to which dfa move on c */
next = move(dfa->states, c);
next = epsilon_closure(next, &accept, 0);
/* no transition */
if (!next)
state = F;
/* transition from current to next */
else if ((state = in_dfa(next)) >= 0)
freeset(next); /* next is alloced by move()*/
else
state = add_dfa(next, accept);
/* real assign the dfatable: [0->ndfas][0->MAX_CHARS] */
dfatable[state_dfa(dfa)][c] = state;
/* NOTE: using state, not ndfas - 1 */
if (accept)
addset(acceptset, state);
}
}
}
void free_dfa(struct dfa *dfa)
{
if (dfa->states) {
freeset(dfa->states);
dfa->states = NULL;
}
if (dfa->accept) {
freeaccept(dfa->accept);
dfa->accept = NULL;
}
}
/*
* subset construction:
* convert NFA directed graph to DFA table
*
* RETURN:
* @table dfa state transtion table
* @acceptset dfa acceptable state set
* return value dfa state transtion table size
*/
int construct_dfa(struct nfa *sstate, int (**table)[], struct set **acceptset)
{
/* dfatable[STATES][CHARS] */
int (*dfatable)[MAX_CHARS];
struct set *accept;
int i;
/* init dfa table */
dfatable = xmalloc(MAX_TABLESIZE * sizeof(int));
/* alloc accept set */
accept = newset();
/*
* init internal dfa auxiliary method,
* which is used in subsetconstruct()
*/
init_dfas(sstate, accept);
/* subset construction */
subsetconstruct(dfatable, accept);
/* adjust dfatable real size */
dfatable = realloc(dfatable, ndfas * MAX_CHARS * sizeof(int));
/* return value */
if (table)
*table = dfatable;
else
free(dfatable);
if (acceptset)
*acceptset = accept;
else
freeset(accept);
return ndfas;
}
/*
- p_bracket - parse a bracketed character list
*
* Note a significant property of this code: if the allocset() did SETERROR,
* no set operations are done.
*/
static void
p_bracket(struct parse *p)
{
cset *cs;
int invert = 0;
/* Dept of Truly Sickening Special-Case Kludges */
if (p->next + 5 < p->end && strncmp(p->next, "[:<:]]", 6) == 0) {
EMIT(OBOW, 0);
NEXTn(6);
return;
}
if (p->next + 5 < p->end && strncmp(p->next, "[:>:]]", 6) == 0) {
EMIT(OEOW, 0);
NEXTn(6);
return;
}
if ((cs = allocset(p)) == NULL) {
/* allocset did set error status in p */
return;
}
if (EAT('^'))
invert++; /* make note to invert set at end */
if (EAT(']'))
CHadd(cs, ']');
else if (EAT('-'))
CHadd(cs, '-');
while (MORE() && PEEK() != ']' && !SEETWO('-', ']'))
p_b_term(p, cs);
if (EAT('-'))
CHadd(cs, '-');
MUSTEAT(']', REG_EBRACK);
if (p->error != 0) { /* don't mess things up further */
freeset(p, cs);
return;
}
if (p->g->cflags®_ICASE) {
int i;
int ci;
for (i = p->g->csetsize - 1; i >= 0; i--)
if (CHIN(cs, i) && isalpha(i)) {
ci = othercase(i);
if (ci != i)
CHadd(cs, ci);
}
if (cs->multis != NULL)
mccase(p, cs);
}
if (invert) {
int i;
for (i = p->g->csetsize - 1; i >= 0; i--)
if (CHIN(cs, i))
CHsub(cs, i);
else
CHadd(cs, i);
if (p->g->cflags®_NEWLINE)
CHsub(cs, '\n');
if (cs->multis != NULL)
mcinvert(p, cs);
}
assert(cs->multis == NULL); /* xxx */
if (nch(p, cs) == 1) { /* optimize singleton sets */
ordinary(p, firstch(p, cs));
freeset(p, cs);
} else
EMIT(OANYOF, freezeset(p, cs));
}
void PhaseLive::compute(uint maxlrg) {
_maxlrg = maxlrg;
_worklist = new (_arena) Block_List();
// Init the sparse live arrays. This data is live on exit from here!
// The _live info is the live-out info.
_live = (IndexSet*)_arena->Amalloc(sizeof(IndexSet)*_cfg._num_blocks);
uint i;
for( i=0; i<_cfg._num_blocks; i++ ) {
_live[i].initialize(_maxlrg);
}
// Init the sparse arrays for delta-sets.
ResourceMark rm; // Nuke temp storage on exit
// Does the memory used by _defs and _deltas get reclaimed? Does it matter? TT
// Array of values defined locally in blocks
_defs = NEW_RESOURCE_ARRAY(IndexSet,_cfg._num_blocks);
for( i=0; i<_cfg._num_blocks; i++ ) {
_defs[i].initialize(_maxlrg);
}
// Array of delta-set pointers, indexed by block pre_order-1.
_deltas = NEW_RESOURCE_ARRAY(IndexSet*,_cfg._num_blocks);
memset( _deltas, 0, sizeof(IndexSet*)* _cfg._num_blocks);
_free_IndexSet = NULL;
// Blocks having done pass-1
VectorSet first_pass(Thread::current()->resource_area());
// Outer loop: must compute local live-in sets and push into predecessors.
uint iters = _cfg._num_blocks; // stat counters
for( uint j=_cfg._num_blocks; j>0; j-- ) {
Block *b = _cfg._blocks[j-1];
// Compute the local live-in set. Start with any new live-out bits.
IndexSet *use = getset( b );
IndexSet *def = &_defs[b->_pre_order-1];
uint i;
for( i=b->_nodes.size(); i>1; i-- ) {
Node *n = b->_nodes[i-1];
if( n->is_Phi() ) break;
// BoxNodes keep their input alive as long as their uses. If we
// see a BoxNode then make its input live to the Root block.
// Because we are solving LIVEness, the input now becomes live
// over the whole procedure, interferencing with everything else
// and getting a private unshared stack slot. YeeeHaw!
MachNode *mach = n->is_Mach();
if( mach && mach->ideal_Opcode() == Op_Box )
getset(_cfg._broot)->insert( _names[n->in(1)->_idx] );
uint r = _names[n->_idx];
def->insert( r );
use->remove( r );
uint cnt = n->req();
for( uint k=1; k<cnt; k++ ) {
Node *nk = n->in(k);
uint nkidx = nk->_idx;
if( _cfg._bbs[nkidx] != b )
use->insert( _names[nkidx] );
}
}
// Remove anything defined by Phis and the block start instruction
for( uint k=i; k>0; k-- ) {
uint r = _names[b->_nodes[k-1]->_idx];
def->insert( r );
use->remove( r );
}
// Push these live-in things to predecessors
for( uint l=1; l<b->num_preds(); l++ ) {
Block *p = _cfg._bbs[b->pred(l)->_idx];
add_liveout( p, use, first_pass );
// PhiNode uses go in the live-out set of prior blocks.
for( uint k=i; k>0; k-- )
add_liveout( p, _names[b->_nodes[k-1]->in(l)->_idx], first_pass );
}
freeset( b );
first_pass.set(b->_pre_order);
// Inner loop: blocks that picked up new live-out values to be propagated
while( _worklist->size() ) {
// !!!!!
// #ifdef ASSERT
iters++;
// #endif
Block *b = _worklist->pop();
IndexSet *delta = getset(b);
assert( delta->count(), "missing delta set" );
// Add new-live-in to predecessors live-out sets
for( uint l=1; l<b->num_preds(); l++ )
add_liveout( _cfg._bbs[b->pred(l)->_idx], delta, first_pass );
freeset(b);
} // End of while-worklist-not-empty
} // End of for-all-blocks-outer-loop
// We explicitly clear all of the IndexSets which we are about to release.
// This allows us to recycle their internal memory into IndexSet's free list.
for( i=0; i<_cfg._num_blocks; i++ ) {
_defs[i].clear();
if (_deltas[i]) {
// Is this always true?
_deltas[i]->clear();
}
}
IndexSet *free = _free_IndexSet;
while (free != NULL) {
IndexSet *temp = free;
free = free->next();
temp->clear();
}
}
