changes to spsc example

diff --git a/spsc-example/queue.h b/spsc-example/queue.h
index 94f98e2782533d351bba55b424d6a2d8a4a2e307..f96f9f09359860530cb3264125787b1c7071dd89 100644 (file)
--- a/spsc-example/queue.h
+++ b/spsc-example/queue.h
@@ -4,38 +4,38 @@
 
 using namespace std;
 
+#define acquire memory_order_acquire
+#define release memory_order_release
+#define relaxed memory_order_relaxed
+
 struct node {
-       node(int d) {
-               data.store(0, memory_order_normal);
-               next.store(0, wildcard(1));
+       node(int idx) {
+               index.store(idx, relaxed);
+               next.store(0, relaxed);
        }
        atomic<node*> next;
-       atomic_int data;
+       atomic<int> index;
 };
 
 class spsc_queue
 {
-       atomic<node*> head, tail;
+       node *head, *tail;
        public:
        spsc_queue() {
-               head = tail = new node(0);
+               head = tail = new node(-1);
        }
-
-       void enqueue(int val) {
-               node* n = new node(val);
-               node *h = head.load(wildcard(2)); 
-               h->next.store(n, wildcard(3));
-               head.store(n, wildcard(4));
+       void enqueue(int idx) {
+               node* n = new node(idx);
+               tail->next.store(n, release);
+               tail = n;
        }
-
-       bool dequeue(int *v) {
-               node* t = tail.load(wildcard(5));
-               node* n = t->next.load(wildcard(6));
-               if (0 == n)
-                       return false;
-               *v = n->data.load(memory_order_normal);
-               tail.store(n, wildcard(7));
-               delete (t);
+       bool dequeue(int *idx) {
+               node *tmp = head;
+               node *n = tmp->next.load(acquire);
+               if (NULL == n) return false;
+               head = n;
+               *idx = n->index.load(relaxed);
+               delete (tmp);
                return true;
        }
 };

diff --git a/spsc-example/spsc-queue.cc b/spsc-example/spsc-queue.cc
index 9f688c491f023328c363796a8128b0b738f41c21..9a5f916ff234a3fcdef9dd018cadc1962a15a577 100644 (file)
--- a/spsc-example/spsc-queue.cc
+++ b/spsc-example/spsc-queue.cc
@@ -1,55 +1,55 @@
 #include <threads.h>
 #include <atomic>
 
-#include "wildcard.h" 
-
+//#include "wildcard.h" 
 using namespace std;
 
+#define acquire memory_order_acquire
+#define release memory_order_release
+#define relaxed memory_order_relaxed
+
 struct node {
-       node(int d) {
-               data.store(d, memory_order_normal);
-               next.store(0, wildcard(1));
+       node(int idx) {
+               index.store(idx, relaxed);
+               next.store(NULL, relaxed);
        }
-       atomic<node*> next;
-       atomic_int data;
-};
+       atomic<node*> next;/*@ \label{line:spscNodeNext} @*/
+       atomic<int> index;/*@ \label{line:spscNodeIndex} @*/
+};/*@ \label{line:spscNodeEnd} @*/
 
-class spsc_queue { 
-       atomic<node*> head, tail;/*@ \label{line:spscBegin} @*/
+class spsc_queue {/*@ \label{line:spscBegin} @*/
+       node *head, *tail;
        public:
        spsc_queue() {
                head = tail = new node(-1);
        }
-       void enqueue(int val) {
-               node* n = new node(val);
-               node *h = head.load(wildcard(2)); 
-               h->next.store(n, wildcard(3));/*@ \label{line:spscRelease} @*/
-               head.store(n, wildcard(4));
+       void enqueue(int idx) {
+               node* n = new node(idx);
+               tail->next.store(n, relaxed); // Should be release/*@ \label{line:spscRelease} @*/
+               tail = n;
        }
-       bool dequeue(int *v) {
-               node* t = tail.load(wildcard(5));
-               node* n = t->next.load(wildcard(6));/*@ \label{line:spscAcquire} @*/
-               if (0 == n)
-                       return false;
-               *v = n->data.load(memory_order_normal);
-               tail.store(n, wildcard(7));
-               delete (t);
+       bool dequeue(int *idx) {
+               node *tmp = head;
+               node *n = tmp->next.load(relaxed); // Should be acquire/*@ \label{line:spscAcquire} @*/
+               if (NULL == n) return false;
+               head = n;
+               *idx = n->index.load(relaxed);
+               delete (tmp);
                return true;
        }
-};
-
+};/*@ \label{line:spscEnd} @*/
 
 spsc_queue *q;/*@ \label{line:testcaseBegin} @*/
 atomic_int arr[2];
 void thrd1() { // Thread 1/*@ \label{line:thrd1} @*/
-       arr[1].store(47, relaxed);
+       arr[1].store(47, relaxed);/*@ \label{line:spscRelaxedStore} @*/
        q->enqueue(1);
 }
 void thrd2() { // Thread 2/*@ \label{line:thrd2} @*/
        int idx;
        if (q->dequeue(&idx))
-               arr[idx].load(relaxed);
-}
+               arr[idx].load(relaxed);/*@ \label{line:spscRelaxedLoad} @*/
+}/*@ \label{line:testcaseEnd} @*/
 
 int user_main(int argc, char **argv)
 {