Add initial HIP_SYNC_NULL_STREAM=0 mode.

This eliminates host-synchronization for null stream.  Instead, the
null-stream uses GPU-side events to wait for other streams.
Default is OFF pending additional testing.

Add enhanced null-stream test.

Also refine HIP_TRACE_API.

hipamd/tests/src/test_common.h

@@ -184,6 +184,20 @@ addCountReverse( const T *A_d,
 }
 
 
+void setDefaultData(size_t numElements, T *A_h, T* B_h, T *C_h)
+{
+    // Initialize the host data:
+    for (size_t i=0; i<numElements; i++) {
+        if (A_h) 
+            (A_h)[i] = 3.146f + i; // Pi
+        if (B_h) 
+            (B_h)[i] = 1.618f + i; // Phi
+        if (C_h) 
+            (C_h)[i] = 0.0f + i;  
+    }
+}
+
+
 template <typename T>
 void initArraysForHost(T **A_h, T **B_h, T **C_h,
                 size_t N, bool usePinnedHost=false)
@@ -217,15 +231,10 @@ void initArraysForHost(T **A_h, T **B_h, T **C_h,
         }
     }
 
-    // Initialize the host data:
-    for (size_t i=0; i<N; i++) {
-        if (A_h) 
-            (*A_h)[i] = 3.146f + i; // Pi
-        if (B_h) 
-            (*B_h)[i] = 1.618f + i; // Phi
-    }
+    setDefaultData(N, A_h ? *A_h : nullptr, B_h ? *B_h : nullptr, C_h ? *C_h : nullptr);
 }
 
+
 template <typename T>
 void initArrays(T **A_d, T **B_d, T **C_d,
                 T **A_h, T **B_h, T **C_h, 
@@ -367,6 +376,43 @@ void checkVectorADD(T* A_h, T* B_h, T* result_H, size_t N, bool expectMatch=true
 }
 
 
+// Assumes C_h contains vector add of A_h + B_h
+// Calls the test "failed" macro if a mismatch is detected.
+template <typename T>
+void checkTest(T* expected_H, T* result_H, size_t N, bool expectMatch=true)
+{
+    size_t  mismatchCount = 0;
+    size_t  firstMismatch = 0;
+    size_t  mismatchesToPrint = 10;
+    for (size_t i=0; i<N; i++) {
+        if (result_H[i] != expected_H[i]) {
+            if (mismatchCount == 0) {
+                firstMismatch = i;
+            }
+            mismatchCount++;
+            if ((mismatchCount <= mismatchesToPrint) && expectMatch) {
+                std::cout << std::fixed << std::setprecision(32);
+                std::cout << "At " << i << std::endl;
+                std::cout << "  Computed:" << result_H[i]  << std::endl;
+                std::cout << "  Expected:" << expected_H[i] << std::endl;
+            }
+        }
+    }
+
+    if (expectMatch) {
+        if (mismatchCount) {
+            fprintf(stderr, "%zu mismatches ; first at index:%zu\n", mismatchCount, firstMismatch);
+            //failed("%zu mismatches ; first at index:%zu\n", mismatchCount, firstMismatch);
+        }
+    } else {
+        if (mismatchCount == 0) {
+            failed("expected mismatches but did not detect any!");
+        }
+    }
+
+}
+
+
 //---
 struct Pinned {
 	static const bool isPinned = true;