/* This callback handles starting execution of a thread. */
static void start_thread(void *data) {
ThreadStart *ts = (ThreadStart *)data;
MVMThreadContext *tc = ts->tc;
/* Set the current frame in the thread to be the initial caller;
* the ref count for this was incremented in the original thread. */
tc->cur_frame = ts->caller;
/* wait for the GC to finish if it's not finished stealing us. */
MVM_gc_mark_thread_unblocked(tc);
tc->thread_obj->body.stage = MVM_thread_stage_started;
/* Enter the interpreter, to run code. */
MVM_interp_run(tc, &thread_initial_invoke, ts);
/* mark as exited, so the GC will know to clear our stuff. */
tc->thread_obj->body.stage = MVM_thread_stage_exited;
/* Now we're done, decrement the reference count of the caller. */
MVM_frame_dec_ref(tc, ts->caller);
/* Mark ourselves as dying, so that another thread will take care
* of GC-ing our objects and cleaning up our thread context. */
MVM_gc_mark_thread_blocked(tc);
/* hopefully pop the ts->thread_obj temp */
MVM_gc_root_temp_pop(tc);
free(ts);
/* Exit the thread, now it's completed. */
MVM_platform_thread_exit(NULL);
}
MVMString * MVM_string_repeat(MVMThreadContext *tc, MVMString *a, MVMint64 count) {
MVMString *result;
MVMint64 bkup_count = count;
MVMStringIndex string_offset = 0, graphs = 0, rgraphs;
if (!IS_CONCRETE((MVMObject *)a)) {
MVM_exception_throw_adhoc(tc, "repeat needs a concrete string");
}
if (count < 0)
MVM_exception_throw_adhoc(tc, "repeat count (%lld) cannot be negative", count);
if (count > (1<<30))
MVM_exception_throw_adhoc(tc, "repeat count > %lld arbitrarily unsupported...", (1<<30));
MVM_gc_root_temp_push(tc, (MVMCollectable **)&a);
result = (MVMString *)REPR(a)->allocate(tc, STABLE(a));
MVM_gc_root_temp_pop(tc);
if (IS_ONE_STRING_ROPE(a)) {
string_offset = a->body.strands->string_offset;
graphs = a->body.strands[1].graphs;
a = a->body.strands->string;
}
else {
graphs = NUM_GRAPHS(a);
}
rgraphs = graphs * count;
/* XXX compute tradeoff here of space usage of the strands table vs real string */
if (rgraphs) {
MVMStrand *strands = result->body.strands = calloc(sizeof(MVMStrand), count + 1);
result->body.flags = MVM_STRING_TYPE_ROPE;
while (count--) {
strands[count].compare_offset = count * graphs;
strands[count].string = a;
strands[count].string_offset = string_offset;
}
strands[bkup_count].graphs = rgraphs;
result->body.num_strands = bkup_count;
_STRAND_DEPTH(result) = STRAND_DEPTH(a) + 1;
}
else {
result->body.flags = MVM_STRING_TYPE_UINT8;
/* leave graphs 0 and storage null */
}
return result;
}
/* XXX inline parent's strands if it's a rope too? */
MVMString * MVM_string_concatenate(MVMThreadContext *tc, MVMString *a, MVMString *b) {
MVMString *result;
MVMStrandIndex strand_count = 0;
MVMStrand *strands;
MVMStringIndex index = 0;
MVMStrandIndex max_strand_depth = 0;
MVMStringIndex agraphs = NUM_GRAPHS(a), bgraphs = NUM_GRAPHS(b), rgraphs;
if (!IS_CONCRETE((MVMObject *)a) || !IS_CONCRETE((MVMObject *)b)) {
MVM_exception_throw_adhoc(tc, "Concatenate needs concrete strings");
}
MVM_gc_root_temp_push(tc, (MVMCollectable **)&a);
result = (MVMString *)REPR(a)->allocate(tc, STABLE(a));
MVM_gc_root_temp_pop(tc);
/* there could be unattached combining chars at the beginning of b,
so, XXX TODO handle this */
result->body.flags = MVM_STRING_TYPE_ROPE;
rgraphs = agraphs + bgraphs;
if (agraphs)
strand_count = 1;
if (bgraphs)
++strand_count;
strands = result->body.strands = calloc(sizeof(MVMStrand), strand_count + 1);
strand_count = 0;
if (agraphs) {
strands->string = a;
strands->string_offset = 0;
strands->compare_offset = index;
index = agraphs;
strand_count = 1;
max_strand_depth = STRAND_DEPTH(a);
}
if (bgraphs) {
strands[strand_count].string = b;
strands[strand_count].string_offset = 0;
strands[strand_count].compare_offset = index;
index += bgraphs;
++strand_count;
if (STRAND_DEPTH(b) > max_strand_depth)
max_strand_depth = STRAND_DEPTH(b);
}
strands[strand_count].graphs = index;
result->body.num_strands = strand_count;
result->body.flags = MVM_STRING_TYPE_ROPE;
_STRAND_DEPTH(result) = max_strand_depth + 1;
return result;
}
/* Returns a substring of the given string */
MVMString * MVM_string_substring(MVMThreadContext *tc, MVMString *a, MVMint64 start, MVMint64 length) {
MVMString *result;
MVMStrand *strands;
MVMStringIndex agraphs = NUM_GRAPHS(a);
if (start < 0) {
start += agraphs;
if (start < 0)
start = 0;
}
if (!IS_CONCRETE((MVMObject *)a)) {
MVM_exception_throw_adhoc(tc, "Substring needs a concrete string");
}
if (start > agraphs)
start = agraphs;
if (length == -1) /* -1 signifies go to the end of the string */
length = agraphs - start;
if (length < 0)
MVM_exception_throw_adhoc(tc, "Substring length (%lld) cannot be negative", length);
if (start + length > agraphs)
length = agraphs - start;
MVM_gc_root_temp_push(tc, (MVMCollectable **)&a);
result = (MVMString *)REPR(a)->allocate(tc, STABLE(a));
MVM_gc_root_temp_pop(tc);
strands = result->body.strands = calloc(sizeof(MVMStrand), 2);
/* if we're substringing a substring, substring the same one */
if (IS_ONE_STRING_ROPE(a)) {
strands->string_offset = (MVMStringIndex)start + a->body.strands->string_offset;
strands->string = a->body.strands->string;
}
else {
strands->string_offset = (MVMStringIndex)start;
strands->string = a;
}
/* result->body.codes = 0; /* Populate this lazily. */
result->body.flags = MVM_STRING_TYPE_ROPE;
result->body.num_strands = 1;
strands[1].graphs = length;
_STRAND_DEPTH(result) = STRAND_DEPTH(strands->string) + 1;
return result;
}
void MVM_thread_join(MVMThreadContext *tc, MVMObject *thread_obj) {
if (REPR(thread_obj)->ID == MVM_REPR_ID_MVMThread) {
MVMThread *thread = (MVMThread *)thread_obj;
int status;
MVM_gc_root_temp_push(tc, (MVMCollectable **)&thread);
MVM_gc_mark_thread_blocked(tc);
if (((MVMThread *)thread_obj)->body.stage < MVM_thread_stage_exited) {
status = uv_thread_join(&thread->body.thread);
}
else { /* the target already ended */
/* used to be APR_SUCCESS, but then we ditched APR */
status = 0;
}
MVM_gc_mark_thread_unblocked(tc);
MVM_gc_root_temp_pop(tc);
if (status < 0)
MVM_panic(MVM_exitcode_compunit, "Could not join thread: errorcode %d", status);
}
else {
MVM_exception_throw_adhoc(tc,
"Thread handle passed to join must have representation MVMThread");
}
}
MVMObject * MVM_thread_start(MVMThreadContext *tc, MVMObject *invokee, MVMObject *result_type) {
int status;
ThreadStart *ts;
MVMObject *child_obj;
/* Create a thread object to wrap it up in. */
MVM_gc_root_temp_push(tc, (MVMCollectable **)&invokee);
child_obj = REPR(result_type)->allocate(tc, STABLE(result_type));
MVM_gc_root_temp_pop(tc);
if (REPR(child_obj)->ID == MVM_REPR_ID_MVMThread) {
MVMThread *child = (MVMThread *)child_obj;
MVMThread * volatile *threads;
/* Create a new thread context and set it up. */
MVMThreadContext *child_tc = MVM_tc_create(tc->instance);
child->body.tc = child_tc;
MVM_ASSIGN_REF(tc, child, child->body.invokee, invokee);
child_tc->thread_obj = child;
child_tc->thread_id = MVM_incr(&tc->instance->next_user_thread_id);
/* Create the thread. Note that we take a reference to the current frame,
* since it must survive to be the dynamic scope of where the thread was
* started, and there's no promises that the thread won't start before
* the code creating the thread returns. The count is decremented when
* the thread is done. */
ts = malloc(sizeof(ThreadStart));
ts->tc = child_tc;
ts->caller = MVM_frame_inc_ref(tc, tc->cur_frame);
ts->thread_obj = child_obj;
/* push this to the *child* tc's temp roots. */
MVM_gc_root_temp_push(child_tc, (MVMCollectable **)&ts->thread_obj);
/* Signal to the GC we have a childbirth in progress. The GC
* will null it for us. */
MVM_gc_mark_thread_blocked(child_tc);
MVM_ASSIGN_REF(tc, tc->thread_obj, tc->thread_obj->body.new_child, child);
/* push to starting threads list */
threads = &tc->instance->threads;
do {
MVMThread *curr = *threads;
MVM_ASSIGN_REF(tc, child, child->body.next, curr);
} while (MVM_casptr(threads, child->body.next, child) != child->body.next);
status = uv_thread_create(&child->body.thread, &start_thread, ts);
if (status < 0) {
MVM_panic(MVM_exitcode_compunit, "Could not spawn thread: errorcode %d", status);
}
/* need to run the GC to clear our new_child field in case we try
* try to launch another thread before the GC runs and before the
* thread starts. */
GC_SYNC_POINT(tc);
}
else {
MVM_exception_throw_adhoc(tc,
"Thread result type must have representation MVMThread");
}
return child_obj;
}