[OpenMP][Tools][Tests][NFC] Address flaky archer tests

Adding more concurrent threads significantly increases the
chance that the data race can be observed during testing.

openmp/tools/archer/tests/races/critical-unrelated.c

@@ -19,7 +19,7 @@
 int main(int argc, char *argv[]) {
   int var = 0;
 
-#pragma omp parallel num_threads(2) shared(var)
+#pragma omp parallel num_threads(8) shared(var)
   {
 #pragma omp critical
     {

openmp/tools/archer/tests/races/lock-nested-unrelated.c

@@ -22,7 +22,7 @@ int main(int argc, char *argv[]) {
   omp_nest_lock_t lock;
   omp_init_nest_lock(&lock);
 
-#pragma omp parallel num_threads(2) shared(var)
+#pragma omp parallel num_threads(8) shared(var)
   {
     omp_set_nest_lock(&lock);
     omp_set_nest_lock(&lock);

openmp/tools/archer/tests/races/lock-unrelated.c

@@ -22,7 +22,7 @@ int main(int argc, char *argv[]) {
   omp_lock_t lock;
   omp_init_lock(&lock);
 
-#pragma omp parallel num_threads(2) shared(var)
+#pragma omp parallel num_threads(8) shared(var)
   {
     omp_set_lock(&lock);
     // Dummy locking.

openmp/tools/archer/tests/races/parallel-simple.c

@@ -19,7 +19,7 @@
 int main(int argc, char *argv[]) {
   int var = 0;
 
-#pragma omp parallel num_threads(2) shared(var)
+#pragma omp parallel num_threads(8) shared(var)
   { var++; }
 
   int error = (var != 2);

openmp/tools/archer/tests/races/task-dependency.c

@@ -21,7 +21,7 @@
 int main(int argc, char *argv[]) {
   int var = 0, a = 0;
 
-#pragma omp parallel num_threads(2) shared(var, a)
+#pragma omp parallel num_threads(8) shared(var, a)
 #pragma omp master
   {
 #pragma omp task shared(var, a) depend(out : var)

openmp/tools/archer/tests/races/task-taskgroup-unrelated.c

@@ -21,7 +21,7 @@
 int main(int argc, char *argv[]) {
   int var = 0, a = 0;
 
-#pragma omp parallel num_threads(2) shared(var, a)
+#pragma omp parallel num_threads(8) shared(var, a)
 #pragma omp master
   {
 #pragma omp task shared(var, a)

openmp/tools/archer/tests/races/task-taskwait-nested.c

@@ -21,7 +21,7 @@
 int main(int argc, char *argv[]) {
   int var = 0, a = 0;
 
-#pragma omp parallel num_threads(2) shared(var, a)
+#pragma omp parallel num_threads(8) shared(var, a)
 #pragma omp master
   {
 #pragma omp task shared(var, a)

openmp/tools/archer/tests/races/task-two.c

@@ -17,7 +17,7 @@
 #include <stdio.h>
 #include <unistd.h>
 
-#define NUM_THREADS 2
+#define NUM_THREADS 8
 
 int main(int argc, char *argv[]) {
   int var = 0;