diff --git a/concurrency/cudaGetLastErrorIsAsynchronous.cu b/concurrency/cudaGetLastErrorIsAsynchronous.cu
new file mode 100644
index 0000000..88f9a1b
--- /dev/null
+++ b/concurrency/cudaGetLastErrorIsAsynchronous.cu
@@ -0,0 +1,111 @@
+/*
+ *
+ * nullKernelAsync.cu
+ *
+ * Microbenchmark for throughput of asynchronous kernel launch.
+ *
+ * Build with: nvcc -I ../chLib <options> nullKernelAsync.cu
+ * Requires: No minimum SM requirement.
+ *
+ * Copyright (c) 2011-2014, Archaea Software, LLC.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions 
+ * are met: 
+ *
+ * 1. Redistributions of source code must retain the above copyright 
+ *    notice, this list of conditions and the following disclaimer. 
+ * 2. Redistributions in binary form must reproduce the above copyright 
+ *    notice, this list of conditions and the following disclaimer in 
+ *    the documentation and/or other materials provided with the 
+ *    distribution. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include <stdio.h>
+#include <iostream>
+
+#include "chError.h"
+#include "chTimer.h"
+
+#ifdef __HIPCC__
+#include <hip/hip_runtime.h>
+
+#define cuda( fn ) do { \
+	    status = (hip##fn); \
+	    if ( hipSuccess != (status) ) { \
+		                goto Error; \
+		            } \
+	    } while (0);
+#endif
+
+__global__
+void
+NullKernel( volatile int *p, bool write, int a=0, int b=1, int c=2, int d=3, int e=4, int f=5, int g=6 )
+{
+    if ( write && 0==threadIdx.x && 0==blockIdx.x ) {
+        *p = a+b+c+d+e+f+g;
+    }
+}
+
+double
+usPerLaunch( int cIterations )
+{
+    cudaError_t status;
+    double microseconds, ret;
+    chTimerTimestamp start, stop;
+    cudaEvent_t ev=0;
+
+    cuda(EventCreate( &ev ) )
+
+    cuda(Free(0));
+
+    chTimerGetTime( &start );
+    for ( int i = 0; i < cIterations; i++ ) {
+        NullKernel<<<1,1>>>( NULL, false );
+    }
+    NullKernel<<<1,1>>>( NULL, true );
+    cuda(EventRecord( ev ));
+    status = cudaEventQuery( ev );
+    std::cout << "cudaEventQuery returned " << status << std::endl;
+    status = cudaGetLastError();
+    std::cout << "cudaGetLastError returned " << status << " (before cudaDeviceSynchronize())" << std::endl;
+
+    // this returns error due to deliberate dereference of NULL on last kernel invocation
+    (void) cudaDeviceSynchronize();
+    status = cudaGetLastError();
+    std::cout << "cudaGetLastError returned " << status << " (after cudaDeviceSynchronize())" << std::endl;
+    cuda(EventDestroy(ev));
+    chTimerGetTime( &stop );
+
+    microseconds = 1e6*chTimerElapsedTime( &start, &stop );
+    ret = microseconds / (float) cIterations;
+
+Error:
+    return (status) ? 0.0 : ret;
+}
+
+int
+main( int argc, char *argv[] )
+{
+    const int cIterations = 100000;
+    printf( "Measuring asynchronous launch time... " ); fflush( stdout );
+
+    printf( "%.2f us\n", usPerLaunch(cIterations) );
+
+    return 0;
+}
diff --git a/concurrency/nullKernelAsync.cu b/concurrency/nullKernelAsync.cu
index 0d3ca09..7d00e75 100644
--- a/concurrency/nullKernelAsync.cu
+++ b/concurrency/nullKernelAsync.cu
@@ -37,14 +37,36 @@
  */
 
 #include <stdio.h>
+#include <iostream>
 
 #include "chError.h"
 #include "chTimer.h"
 
+<<<<<<< Updated upstream
 __global__
 void
 NullKernel()
 {
+=======
+#ifdef __HIPCC__
+#include <hip/hip_runtime.h>
+
+#define cuda( fn ) do { \
+	    status = (hip##fn); \
+	    if ( hipSuccess != (status) ) { \
+		                goto Error; \
+		            } \
+	    } while (0);
+#endif
+
+__global__
+void
+NullKernel( volatile int *p, bool write, int a=0, int b=1, int c=2, int d=3, int e=4, int f=5, int g=6 )
+{
+    if ( write && 0==threadIdx.x && 0==blockIdx.x ) {
+        *p = a+b+c+d+e+f+g;
+    }
+>>>>>>> Stashed changes
 }
 
 double
@@ -53,6 +75,9 @@ usPerLaunch( int cIterations )
     cudaError_t status;
     double microseconds, ret;
     chTimerTimestamp start, stop;
+    cudaEvent_t ev=0;
+
+    cuda(EventCreate( &ev ) )
 
     cuda(Free(0));
 
@@ -60,7 +85,15 @@ usPerLaunch( int cIterations )
     for ( int i = 0; i < cIterations; i++ ) {
         NullKernel<<<1,1>>>();
     }
+    NullKernel<<<1,1>>>( NULL, true );
+    cuda(EventRecord( ev ));
+    status = cudaEventQuery( ev );
+    std::cout << "cudaEventQuery returned " << status << std::endl;
+    status = cudaGetLastError();
+    std::cout << "cudaGetLastError returned " << status << std::endl;
+
     cuda(DeviceSynchronize());
+    cuda(EventDestroy(ev));
     chTimerGetTime( &stop );
 
     microseconds = 1e6*chTimerElapsedTime( &start, &stop );