static void zend_mark_reachable(zend_op *opcodes, zend_basic_block *blocks, zend_basic_block *b) /* {{{ */
{
zend_uchar opcode;
zend_basic_block *b0;
int successor_0, successor_1;
while (1) {
b->flags |= ZEND_BB_REACHABLE;
successor_0 = b->successors[0];
if (successor_0 >= 0) {
successor_1 = b->successors[1];
if (successor_1 >= 0) {
b0 = blocks + successor_0;
b0->flags |= ZEND_BB_TARGET;
if (!(b0->flags & ZEND_BB_REACHABLE)) {
zend_mark_reachable(opcodes, blocks, b0);
}
opcode = opcodes[b->end].opcode;
b = blocks + successor_1;
if (opcode == ZEND_JMPZNZ) {
b->flags |= ZEND_BB_TARGET;
} else {
b->flags |= ZEND_BB_FOLLOW;
}
} else {
opcode = opcodes[b->end].opcode;
b = blocks + successor_0;
if (opcode == ZEND_JMP) {
b->flags |= ZEND_BB_TARGET;
} else {
b->flags |= ZEND_BB_FOLLOW;
//TODO: support for stackless CFG???
if (0/*stackless*/) {
if (opcode == ZEND_INCLUDE_OR_EVAL ||
opcode == ZEND_YIELD ||
opcode == ZEND_YIELD_FROM ||
opcode == ZEND_DO_FCALL ||
opcode == ZEND_DO_UCALL ||
opcode == ZEND_DO_FCALL_BY_NAME) {
b->flags |= ZEND_BB_ENTRY;
}
}
}
}
if (b->flags & ZEND_BB_REACHABLE) return;
} else {
b->flags |= ZEND_BB_EXIT;
return;
}
}
}
static void zend_mark_reachable_blocks(const zend_op_array *op_array, zend_cfg *cfg, int start) /* {{{ */
{
zend_basic_block *blocks = cfg->blocks;
blocks[start].flags = ZEND_BB_START;
zend_mark_reachable(op_array->opcodes, blocks, blocks + start);
if (op_array->last_live_range || op_array->last_try_catch) {
zend_basic_block *b;
int j, changed;
uint32_t *block_map = cfg->map;
do {
changed = 0;
/* Add brk/cont paths */
for (j = 0; j < op_array->last_live_range; j++) {
if (op_array->live_range[j].var == (uint32_t)-1) {
/* this live range already removed */
continue;
}
b = blocks + block_map[op_array->live_range[j].start];
if (b->flags & ZEND_BB_REACHABLE) {
while (op_array->opcodes[b->start].opcode == ZEND_NOP && b->start != b->end) {
b->start++;
}
if (op_array->opcodes[b->start].opcode == ZEND_NOP &&
b->start == b->end &&
b->successors[0] == block_map[op_array->live_range[j].end]) {
/* mark as removed (empty live range) */
op_array->live_range[j].var = (uint32_t)-1;
continue;
}
b->flags |= ZEND_BB_GEN_VAR;
b = blocks + block_map[op_array->live_range[j].end];
b->flags |= ZEND_BB_KILL_VAR;
if (!(b->flags & ZEND_BB_REACHABLE)) {
changed = 1;
zend_mark_reachable(op_array->opcodes, blocks, b);
}
} else {
ZEND_ASSERT(!(blocks[block_map[op_array->live_range[j].end]].flags & ZEND_BB_REACHABLE));
}
}
/* Add exception paths */
for (j = 0; j < op_array->last_try_catch; j++) {
/* check for jumps into the middle of try block */
b = blocks + block_map[op_array->try_catch_array[j].try_op];
if (!(b->flags & ZEND_BB_REACHABLE)) {
zend_basic_block *end;
if (op_array->try_catch_array[j].catch_op) {
end = blocks + block_map[op_array->try_catch_array[j].catch_op];
while (b != end) {
if (b->flags & ZEND_BB_REACHABLE) {
op_array->try_catch_array[j].try_op = b->start;
break;
}
b++;
}
}
b = blocks + block_map[op_array->try_catch_array[j].try_op];
if (!(b->flags & ZEND_BB_REACHABLE)) {
if (op_array->try_catch_array[j].finally_op) {
end = blocks + block_map[op_array->try_catch_array[j].finally_op];
while (b != end) {
if (b->flags & ZEND_BB_REACHABLE) {
op_array->try_catch_array[j].try_op = op_array->try_catch_array[j].catch_op;
changed = 1;
zend_mark_reachable(op_array->opcodes, blocks, blocks + block_map[op_array->try_catch_array[j].try_op]);
break;
}
b++;
}
}
}
}
b = blocks + block_map[op_array->try_catch_array[j].try_op];
if (b->flags & ZEND_BB_REACHABLE) {
b->flags |= ZEND_BB_TRY;
if (op_array->try_catch_array[j].catch_op) {
b = blocks + block_map[op_array->try_catch_array[j].catch_op];
b->flags |= ZEND_BB_CATCH;
if (!(b->flags & ZEND_BB_REACHABLE)) {
changed = 1;
zend_mark_reachable(op_array->opcodes, blocks, b);
}
}
if (op_array->try_catch_array[j].finally_op) {
b = blocks + block_map[op_array->try_catch_array[j].finally_op];
b->flags |= ZEND_BB_FINALLY;
if (!(b->flags & ZEND_BB_REACHABLE)) {
changed = 1;
zend_mark_reachable(op_array->opcodes, blocks, b);
}
}
if (op_array->try_catch_array[j].finally_end) {
b = blocks + block_map[op_array->try_catch_array[j].finally_end];
b->flags |= ZEND_BB_FINALLY_END;
if (!(b->flags & ZEND_BB_REACHABLE)) {
changed = 1;
zend_mark_reachable(op_array->opcodes, blocks, b);
}
}
} else {
if (op_array->try_catch_array[j].catch_op) {
ZEND_ASSERT(!(blocks[block_map[op_array->try_catch_array[j].catch_op]].flags & ZEND_BB_REACHABLE));
}
if (op_array->try_catch_array[j].finally_op) {
ZEND_ASSERT(!(blocks[block_map[op_array->try_catch_array[j].finally_op]].flags & ZEND_BB_REACHABLE));
}
if (op_array->try_catch_array[j].finally_end) {
ZEND_ASSERT(!(blocks[block_map[op_array->try_catch_array[j].finally_end]].flags & ZEND_BB_REACHABLE));
}
}
}
} while (changed);
}
}
static void zend_mark_reachable_blocks(zend_op_array *op_array, zend_cfg *cfg, int start)
{
zend_basic_block *blocks = cfg->blocks;
blocks[start].flags = ZEND_BB_START;
zend_mark_reachable(op_array->opcodes, blocks, blocks + start);
if (op_array->last_live_range || op_array->last_try_catch) {
zend_basic_block *b;
int j, changed;
uint32_t *block_map = cfg->map;
do {
changed = 0;
/* Add brk/cont paths */
for (j = 0; j < op_array->last_live_range; j++) {
b = blocks + block_map[op_array->live_range[j].start];
if (b->flags & ZEND_BB_REACHABLE) {
b->flags |= ZEND_BB_GEN_VAR;
b = blocks + block_map[op_array->live_range[j].end];
b->flags |= ZEND_BB_KILL_VAR;
if (!(b->flags & ZEND_BB_REACHABLE)) {
changed = 1;
zend_mark_reachable(op_array->opcodes, blocks, b);
}
} else {
ZEND_ASSERT(!(blocks[block_map[op_array->live_range[j].end]].flags & ZEND_BB_REACHABLE));
}
}
/* Add exception paths */
for (j = 0; j < op_array->last_try_catch; j++) {
/* check for jumps into the middle of try block */
b = blocks + block_map[op_array->try_catch_array[j].try_op];
if (!(b->flags & ZEND_BB_REACHABLE)) {
zend_basic_block *end;
if (op_array->try_catch_array[j].catch_op) {
end = blocks + block_map[op_array->try_catch_array[j].catch_op];
while (b != end) {
if (b->flags & ZEND_BB_REACHABLE) {
op_array->try_catch_array[j].try_op = b->start;
break;
}
b++;
}
}
b = blocks + block_map[op_array->try_catch_array[j].try_op];
if (!(b->flags & ZEND_BB_REACHABLE)) {
if (op_array->try_catch_array[j].finally_op) {
end = blocks + block_map[op_array->try_catch_array[j].finally_op];
while (b != end) {
if (b->flags & ZEND_BB_REACHABLE) {
op_array->try_catch_array[j].try_op = op_array->try_catch_array[j].catch_op;
changed = 1;
zend_mark_reachable(op_array->opcodes, blocks, blocks + block_map[op_array->try_catch_array[j].try_op]);
break;
}
b++;
}
}
}
}
b = blocks + block_map[op_array->try_catch_array[j].try_op];
if (b->flags & ZEND_BB_REACHABLE) {
b->flags |= ZEND_BB_TRY;
if (op_array->try_catch_array[j].catch_op) {
b = blocks + block_map[op_array->try_catch_array[j].catch_op];
b->flags |= ZEND_BB_CATCH;
if (!(b->flags & ZEND_BB_REACHABLE)) {
changed = 1;
zend_mark_reachable(op_array->opcodes, blocks, b);
}
}
if (op_array->try_catch_array[j].finally_op) {
b = blocks + block_map[op_array->try_catch_array[j].finally_op];
b->flags |= ZEND_BB_FINALLY;
if (!(b->flags & ZEND_BB_REACHABLE)) {
changed = 1;
zend_mark_reachable(op_array->opcodes, blocks, b);
}
}
if (op_array->try_catch_array[j].finally_end) {
b = blocks + block_map[op_array->try_catch_array[j].finally_end];
b->flags |= ZEND_BB_FINALLY_END;
if (!(b->flags & ZEND_BB_REACHABLE)) {
changed = 1;
zend_mark_reachable(op_array->opcodes, blocks, b);
}
}
} else {
if (op_array->try_catch_array[j].catch_op) {
ZEND_ASSERT(!(blocks[block_map[op_array->try_catch_array[j].catch_op]].flags & ZEND_BB_REACHABLE));
}
if (op_array->try_catch_array[j].finally_op) {
ZEND_ASSERT(!(blocks[block_map[op_array->try_catch_array[j].finally_op]].flags & ZEND_BB_REACHABLE));
}
if (op_array->try_catch_array[j].finally_end) {
ZEND_ASSERT(!(blocks[block_map[op_array->try_catch_array[j].finally_end]].flags & ZEND_BB_REACHABLE));
}
}
}
} while (changed);
}
}
