--- /dev/null
+CC=../clang
+CXX=../clang++
+
+CXXFLAGS=-std=c++11 -pthread -Wall -g
+
+SEQLOCK = seqlock-test
+RWLOCK = rwlock-test
+
+all: $(SEQLOCK) $(RWLOCK)
+
+$(SEQLOCK): $(SEQLOCK).cc
+ $(CXX) -o $@ $< $(CXXFLAGS) $(LDFLAGS)
+
+$(RWLOCK): $(RWLOCK).cc
+ $(CXX) -o $@ $< $(CXXFLAGS) $(LDFLAGS)
+
+clean:
+ rm -f $(SEQLOCK) $(RWLOCK) *.o
--- /dev/null
+#include <stdio.h>
+#include <atomic>
+#include <pthread.h>
+#include <assert.h>
+// #include <stdatomic.h>
+
+using namespace std;
+
+#define RW_LOCK_BIAS 0x00100000
+#define WRITE_LOCK_CMP RW_LOCK_BIAS
+
+/** Example implementation of linux rw lock along with 2 thread test
+ * driver... */
+
+typedef union {
+ atomic_int lock;
+} rwlock_t;
+
+static inline void read_lock(rwlock_t *rw)
+{
+ int priorvalue = rw->lock.fetch_sub(1, memory_order_acquire);
+ while (priorvalue <= 0) {
+ rw->lock.fetch_add(1, memory_order_relaxed);
+ while (rw->lock.load(memory_order_relaxed) <= 0) {
+ pthread_yield();
+ }
+ priorvalue = rw->lock.fetch_sub(1, memory_order_acquire);
+ }
+}
+
+// Injected bug for the two fetch_sub ***
+static inline void write_lock(rwlock_t *rw)
+{
+ int priorvalue = rw->lock.fetch_sub(RW_LOCK_BIAS, memory_order_relaxed); // Should be acquire
+ while (priorvalue != RW_LOCK_BIAS) {
+ rw->lock.fetch_add(RW_LOCK_BIAS, memory_order_relaxed);
+ while (rw->lock.load(memory_order_relaxed) != RW_LOCK_BIAS) {
+ pthread_yield();
+ }
+ priorvalue = rw->lock.fetch_sub(RW_LOCK_BIAS, memory_order_relaxed); // Should be acquire
+ }
+}
+
+static inline void read_unlock(rwlock_t *rw)
+{
+ rw->lock.fetch_add(1, memory_order_release);
+}
+
+static inline void write_unlock(rwlock_t *rw)
+{
+ rw->lock.fetch_add(RW_LOCK_BIAS, memory_order_release);
+}
+
+rwlock_t mylock;
+atomic_int data1, data2;
+
+void * a(void *obj)
+{
+ int i;
+ for(i = 0; i < 4; i++) {
+ if ((i % 2) == 0) {
+ read_lock(&mylock);
+ int d1 = data1.load(memory_order_relaxed);
+ int d2 = data2.load(memory_order_relaxed);
+ assert(d1 == d2);
+ read_unlock(&mylock);
+ } else {
+ write_lock(&mylock);
+ data1.store(i, memory_order_relaxed);
+ data2.store(i, memory_order_relaxed);
+ write_unlock(&mylock);
+ }
+ }
+
+ return NULL;
+}
+
+int main(int argc, char **argv)
+{
+ pthread_t t1, t2, t3;
+ mylock.lock.store(RW_LOCK_BIAS);
+
+ pthread_create(&t1, NULL, &a, NULL);
+ pthread_create(&t2, NULL, &a, NULL);
+ pthread_create(&t3, NULL, &a, NULL);
+
+ pthread_join(t1, NULL);
+ pthread_join(t2, NULL);
+ pthread_join(t3, NULL);
+
+ return 0;
+}
--- /dev/null
+#include <pthread.h>
+#include <atomic>
+#include <assert.h>
+//#include <threads.h>
+
+using namespace std;
+
+typedef struct seqlock {
+ // Sequence for reader consistency check
+ atomic_int _seq;
+ // It needs to be atomic to avoid data races
+ atomic_int _data1;
+ atomic_int _data2;
+
+ seqlock() {
+ _seq.store(0);
+ _data1.store(0);
+ _data2.store(0);
+ }
+
+ void read(int * d1, int *d2) {
+ while (true) {
+ int old_seq = _seq.load(memory_order_acquire);
+ if (old_seq % 2 == 1) continue;
+
+ *d1 = _data1.load(memory_order_acquire);
+ *d2 = _data2.load(memory_order_acquire);
+ if (_seq.load(memory_order_relaxed) == old_seq) {
+ return;
+ }
+ }
+ }
+
+ void write(int new_data, int new_data2) {
+ while (true) {
+ int old_seq = _seq.load(memory_order_relaxed); // Injected bug: should be acquire
+ if (old_seq % 2 == 1)
+ continue; // Retry
+
+ if (_seq.compare_exchange_strong(old_seq, old_seq + 1,
+ memory_order_relaxed, memory_order_relaxed))
+ break;
+ }
+
+ // Update the data
+ _data1.store(new_data, memory_order_release);
+ _data2.store(new_data, memory_order_release);
+
+ _seq.fetch_add(1, memory_order_release);
+ }
+
+} seqlock_t;
+
+
+seqlock_t *lock;
+
+void * a(void *obj) {
+ lock->write(3,3);
+ return NULL;
+}
+
+void * b(void *obj) {
+ lock->write(2,2);
+ return NULL;
+}
+
+void * c(void *obj) {
+ int r1, r2;
+ lock->read(&r1, &r2);
+ assert(r1 == r2);
+ return NULL;
+}
+
+int main(int argc, char **argv) {
+ lock = new seqlock_t();
+
+ pthread_t t1, t2, t3;
+ pthread_create(&t1, NULL, &a, NULL);
+ pthread_create(&t2, NULL, &b, NULL);
+ pthread_create(&t3, NULL, &c, NULL);
+
+ pthread_join(t1, NULL);
+ pthread_join(t2, NULL);
+ pthread_join(t3, NULL);
+
+ return 0;
+}
--- /dev/null
+#!/bin/bash
+
+EXE=$1
+TOTAL_RUN=1000
+CDSLIB="/home/vagrant/c11tester"
+export LD_LIBRARY_PATH=${CDSLIB}
+export C11TESTER='-x1'
+
+COUNT_ASSERT=0
+COUNT_TIME=0
+
+for i in `seq 1 1 $TOTAL_RUN` ; do
+ OUTPUT="$(/usr/bin/time -f "time: %U %S" $EXE 2>&1)"
+ ASSERT="$(echo "$OUTPUT" | grep "Assertion")"
+ if [ -n "$ASSERT" ] ; then
+ ((++COUNT_ASSERT))
+ fi
+
+ TIME="$(echo "$OUTPUT" | grep -o "time: .\... .\...")"
+ TIME_USER_S="$(echo "$TIME" | cut -d' ' -f2 | cut -d'.' -f1)"
+ TIME_USER_CS="$(echo "$TIME" | cut -d' ' -f2 | cut -d'.' -f2)"
+ TIME_SYSTEM_S="$(echo "$TIME" | cut -d' ' -f3 | cut -d'.' -f1)"
+ TIME_SYSTEM_CS="$(echo "$TIME" | cut -d' ' -f3 | cut -d'.' -f2)"
+
+ TIME_EXE=$((10#$TIME_USER_S * 1000 + 10#$TIME_USER_CS * 10 + 10#$TIME_SYSTEM_S * 1000 + 10#$TIME_SYSTEM_CS * 10))
+ COUNT_TIME=$((COUNT_TIME + TIME_EXE))
+done
+
+AVG_ASSERT=$(echo "${COUNT_ASSERT} * 100 / ${TOTAL_RUN}" | bc -l | xargs printf "%.1f")
+
+# -3 / log(1 - p) < n
+echo "Runs: $TOTAL_RUN | Assertions: $COUNT_ASSERT | Total time: ${COUNT_TIME}ms | Assert rate: ${AVG_ASSERT}%"
+rm C11FuzzerTmp* 2> /dev/null
--- /dev/null
+#!/bin/bash
+set -e
+set -u
+
+# Paul: skip `spsc-queue` as it deadlocks.
+
+for t in seqlock-test rwlock-test; do
+ echo -n "$t "
+ ./test.sh ./$t
+done
+