hipHostMalloc allocation are mapped to all devices by default.

Support hipHostMallocPortable flag.
Default flags are hipHostMallocPortable | hipHostMallocMapped.

Also:
-refactor tests to move addCount and addCountReverse into HipTest
namespace.
-test multi-GPU host memory.

hipamd/tests/src/test_common.h

@@ -146,6 +146,44 @@ vectorADD(hipLaunchParm lp,
 }
 
 
+template <typename T>
+__global__ void
+addCount( const T *A_d,
+        T *C_d,
+        size_t NELEM,
+        int count)
+{
+    size_t offset = (hipBlockIdx_x * hipBlockDim_x + hipThreadIdx_x);
+    size_t stride = hipBlockDim_x * hipGridDim_x ;
+
+    // Deliberately do this in an inefficient way to increase kernel runtime
+    for (int i=0; i<count; i++) {
+        for (size_t i=offset; i<NELEM; i+=stride) {
+            C_d[i] = A_d[i] + (T)count;
+        }
+    }
+}
+
+
+template <typename T>
+__global__ void
+addCountReverse( const T *A_d,
+        T *C_d,
+        int64_t NELEM,
+        int count)
+{
+    size_t offset = (hipBlockIdx_x * hipBlockDim_x + hipThreadIdx_x);
+    size_t stride = hipBlockDim_x * hipGridDim_x ;
+
+    // Deliberately do this in an inefficient way to increase kernel runtime
+    for (int i=0; i<count; i++) {
+        for (int64_t i=NELEM-stride+offset; i>=0; i-=stride) {
+            C_d[i] = A_d[i] + (T)count;
+        }
+    }
+}
+
+
 template <typename T>
 void initArraysForHost(T **A_h, T **B_h, T **C_h,
                 size_t N, bool usePinnedHost=false)