*/
int take(Deque *q) {
size_t b = atomic_load_explicit(&q->bottom, memory_order_relaxed) - 1;
- Array *a = (Array *) atomic_load_explicit(&q->array, memory_order_relaxed);
- atomic_store_explicit(&q->bottom, b, memory_order_relaxed);
- atomic_thread_fence(memory_order_seq_cst);
- size_t t = atomic_load_explicit(&q->top, memory_order_relaxed);
/**
@Begin
- @Commit_point_define_check: t > b
- @Label: Take_Point_1
+ @Commit_point_define_check: true
+ @Label: TakeReadBottom
@End
*/
+ Array *a = (Array *) atomic_load_explicit(&q->array, memory_order_relaxed);
+ atomic_store_explicit(&q->bottom, b, memory_order_relaxed);
+ /**** SPEC (sequential) (testcase1.c) ****/
+ atomic_thread_fence(memory_order_seq_cst);
+ size_t t = atomic_load_explicit(&q->top, memory_order_relaxed);
int x;
if (t <= b) {
+ /**
+ @Begin
+ @Commit_point_clear: true
+ @Label: TakeClear1
+ @End
+ */
+
/* Non-empty queue. */
- int size = atomic_load_explicit(&a->size, memory_order_relaxed);
- if (size == 0)
- model_print("take: size == 0\n");
- // TODO: size can be zero here!!
+ int size = atomic_load_explicit(&a->size,memory_order_relaxed);
x = atomic_load_explicit(&a->buffer[b % size], memory_order_relaxed);
/**
@Begin
- @Commit_point_define_check: t != b
- @Label: Take_Point2
+ @Commit_point_define_check: true
+ @Label: TakeReadBuffer
@End
*/
if (t == b) {
/* Single last element in queue. */
+ //FIXME: weaken the following seq_cst causes no spec problem
bool succ = atomic_compare_exchange_strong_explicit(&q->top, &t, t +
1, memory_order_seq_cst, memory_order_relaxed);
- /**
- @Begin
- @Commit_point_define_check: succ == true
- @Label: Take_Point3
- @End
- */
-
- /**
- @Begin
- @Commit_point_define_check: succ == false
- @Label: Take_Point4
- @End
- */
if (!succ) {
+ /**
+ @Begin
+ @Commit_point_clear: true
+ @Label: TakeClear2
+ @End
+ */
+
+ /**
+ @Begin
+ @Commit_point_define_check: true
+ @Label: TakeReadTop
+ @End
+ */
+
/* Failed race. */
x = EMPTY;
}
size_t bottom=atomic_load_explicit(&q->bottom, memory_order_relaxed);
atomic_store_explicit(&new_a->size, new_size, memory_order_relaxed);
size_t i;
+
+ // Initialize the whole new array to turn off the CDSChecker UL error
+ // Check if CDSSpec checker can catch this bug
+ /*
+ for(i=0; i < new_size; i++) {
+ atomic_store_explicit(&new_a->buffer[i % new_size], atomic_load_explicit(&a->buffer[i % size], memory_order_relaxed), memory_order_relaxed);
+ }
+ */
for(i=top; i < bottom; i++) {
- if (new_size == 0)
- model_print("resize: new_size == 0\n");
- if (size == 0)
- model_print("resize: size == 0\n");
atomic_store_explicit(&new_a->buffer[i % new_size], atomic_load_explicit(&a->buffer[i % size], memory_order_relaxed), memory_order_relaxed);
}
+ /**** detected UL ****/
atomic_store_explicit(&q->array, new_a, memory_order_release);
- printf("resize\n");
+ //printf("resize\n");
}
/**
*/
void push(Deque *q, int x) {
size_t b = atomic_load_explicit(&q->bottom, memory_order_relaxed);
+ /**** SPEC (sequential) ****/
size_t t = atomic_load_explicit(&q->top, memory_order_acquire);
Array *a = (Array *) atomic_load_explicit(&q->array, memory_order_relaxed);
if (b - t > atomic_load_explicit(&a->size, memory_order_relaxed) - 1) /* Full queue. */ {
resize(q);
+ // CDSSpec can actually detect the same bug if we avoid the UL error
//Bug in paper...should have next line...
a = (Array *) atomic_load_explicit(&q->array, memory_order_relaxed);
}
int size = atomic_load_explicit(&a->size, memory_order_relaxed);
- if (size == 0)
- model_print("push: size == 0\n");
+
atomic_store_explicit(&a->buffer[b % size], x, memory_order_relaxed);
- atomic_thread_fence(memory_order_release);
/**
@Begin
@Commit_point_define_check: true
- @Label: Push_Point
+ @Label: PushUpdateBuffer
@End
*/
+ /**** UL & SPEC (Sync) (run with -u100 to avoid the uninitialized bug) ****/
+ atomic_thread_fence(memory_order_release);
atomic_store_explicit(&q->bottom, b + 1, memory_order_relaxed);
+
}
/**
@End
*/
int steal(Deque *q) {
+ //Watch out: actually on need to be an acquire (don't count it)
+ // An old bug
size_t t = atomic_load_explicit(&q->top, memory_order_acquire);
- atomic_thread_fence(memory_order_seq_cst);
- size_t b = atomic_load_explicit(&q->bottom, memory_order_acquire);
/**
@Begin
- @Commit_point_define_check: t >= b
- @Label: Steal_Point1
+ @Commit_point_define_check: true
+ @Label: StealReadTop1
@End
*/
+ /********** SPEC error (testcase3.c) **********/
+ atomic_thread_fence(memory_order_seq_cst);
+ /**** SPEC & UL ****/
+ size_t b = atomic_load_explicit(&q->bottom, memory_order_acquire);
+
int x = EMPTY;
if (t < b) {
- /* Non-empty queue. */
- Array *a = (Array *) atomic_load_explicit(&q->array, memory_order_acquire);
- int size = atomic_load_explicit(&a->size, memory_order_relaxed);
- if (size == 0)
- model_print("steal: size == 0\n");
- x = atomic_load_explicit(&a->buffer[t % size], memory_order_relaxed);
- bool succ = atomic_compare_exchange_strong_explicit(&q->top, &t, t + 1,
- memory_order_seq_cst, memory_order_relaxed);
/**
@Begin
- @Commit_point_define_check: succ == true
- @Label: Steal_Point2
+ @Commit_point_clear: true
+ @Label: StealClear1
@End
*/
-
+
+ /* Non-empty queue. */
+ /**** detected UL ****/
+ Array *a = (Array *) atomic_load_explicit(&q->array, memory_order_acquire);
+ int size = atomic_load_explicit(&a->size, memory_order_relaxed);
+ x = atomic_load_explicit(&a->buffer[t % size], memory_order_relaxed);
/**
@Begin
- @Commit_point_define_check: succ == false
- @Label: Steal_Point3
+ @Commit_point_define_check: true
+ @Label: StealReadBuffer
@End
*/
+ /**** SPEC (sequential) ****/
+ bool succ = atomic_compare_exchange_strong_explicit(&q->top, &t, t + 1,
+ memory_order_seq_cst, memory_order_relaxed);
if (!succ) {
+ /**
+ @Begin
+ @Commit_point_clear: true
+ @Label: StealClear2
+ @End
+ */
+
+ /**
+ @Begin
+ @Commit_point_define_check: true
+ @Label: StealReadTop2
+ @End
+ */
+
/* Failed race. */
return ABORT;
}
projects / cdsspec-compiler.git / blobdiff