changes

[model-checker-benchmarks.git] / concurrent-hashmap / hashmap.h

diff --git a/concurrent-hashmap/hashmap.h b/concurrent-hashmap/hashmap.h
index 3014c70e84ca16851a9345c8d05a4405a161e640..8e6f196cb0e8c73d8a02f9dee01b152dddea7cc9 100644 (file)
--- a/concurrent-hashmap/hashmap.h
+++ b/concurrent-hashmap/hashmap.h
@@ -14,6 +14,9 @@
 #include <stdlib.h>
 #include <mutex>
 
+#include "common.h"
+#include "sc_annotation.h"
+
 #define relaxed memory_order_relaxed
 #define release memory_order_release
 #define acquire memory_order_acquire
@@ -157,7 +160,16 @@ class HashMap {
                Value *res = NULL;
 
                // Should be a load acquire
+               // This load action here makes it problematic for the SC analysis, what
+               // we need to do is as follows: if the get() method ever acquires the
+               // lock, we ignore this operation for the SC analysis, and otherwise we
+               // take it into consideration
+               
+               //SC_BEGIN();
                Entry *firstPtr = first->load(acquire);
+               //SC_KEEP();
+               //SC_END();
+
                e = firstPtr;
                while (e != NULL) {
                        if (e->hash == hash && eq(key, e->key)) {
@@ -166,9 +178,9 @@ class HashMap {
                                        return res;
                                else
                                        break;
-                               // Loading the next entry
-                               e = e->next.load(acquire);
                        }
+                       // Loading the next entry
+                       e = e->next.load(acquire);
                }
        
                // Recheck under synch if key apparently not there or interference
@@ -183,6 +195,7 @@ class HashMap {
                        while (e != NULL) {
                                if (e->hash == hash && eq(key, e->key)) {
                                        res = e->value.load(seq_cst);
+                                       seg->unlock(); // Critical region ends
                                        return res;
                                }
                                // Synchronized by locking
@@ -266,8 +279,10 @@ class HashMap {
                // with the previous put())?? 
                oldValue = e->value.load(acquire);
                // If the value parameter is NULL, we will remove the entry anyway
-               if (value != NULL && value->equals(oldValue))
+               if (value != NULL && value->equals(oldValue)) {
+                       seg->unlock();
                        return NULL;
+               }
 
                // Force the get() to grab the lock and retry
                e->value.store(NULL, relaxed);