#include <stdlib.h>
#include <stdio.h>
+inline bool fail(int ret) {
+ return ret == ABORT || ret == EMPTY;
+}
+
Deque * create() {
Deque * q = (Deque *) calloc(1, sizeof(Deque));
Array * a = (Array *) calloc(1, sizeof(Array)+2*sizeof(atomic_int));
return q;
}
+
+/**
+ @Begin
+ @Interface_define: Take
+ @End
+*/
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);
+ /**** 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) {
/* Non-empty queue. */
- x = atomic_load_explicit(&a->buffer[b % atomic_load_explicit(&a->size,memory_order_relaxed)], memory_order_relaxed);
+ 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: true
+ @Label: TakeReadBuffer
+ @End
+ */
if (t == b) {
/* Single last element in queue. */
- if (!atomic_compare_exchange_strong_explicit(&q->top, &t, t + 1, memory_order_seq_cst, memory_order_relaxed))
+ //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);
+ if (!succ) {
/* Failed race. */
x = EMPTY;
+ }
atomic_store_explicit(&q->bottom, b + 1, memory_order_relaxed);
}
} else { /* Empty queue. */
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++) {
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");
}
+/**
+ @Begin
+ @Interface_define: Push
+ @End
+*/
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);
}
- atomic_store_explicit(&a->buffer[b % atomic_load_explicit(&a->size, memory_order_relaxed)], x, memory_order_relaxed);
+ int size = atomic_load_explicit(&a->size, memory_order_relaxed);
+
+ atomic_store_explicit(&a->buffer[b % size], x, memory_order_relaxed);
+ /** @OPDefine: true */
+
+ /**** 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);
+
}
+/**
+ @Begin
+ @Interface_define: Steal
+ @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);
+ /**
+ @Begin
+ @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) {
+ /**
+ @Begin
+ @Commit_point_clear: true
+ @Label: StealClear1
+ @End
+ */
+
/* Non-empty queue. */
+ /**** detected UL ****/
Array *a = (Array *) atomic_load_explicit(&q->array, memory_order_acquire);
- x = atomic_load_explicit(&a->buffer[t % atomic_load_explicit(&a->size, memory_order_relaxed)], memory_order_relaxed);
- if (!atomic_compare_exchange_strong_explicit(&q->top, &t, t + 1, memory_order_seq_cst, memory_order_relaxed))
+ 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: 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;
+ }
}
return x;
}