[gcc/devel/omp/gcc-9] [og9] Fix libgomp serial-dims.c test for AMD GCN

[Thomas Schwinge]

https://gcc.gnu.org/g:de5b5fcdd6934bc58a28cd34a12930cf87bd7551

commit de5b5fcdd6934bc58a28cd34a12930cf87bd7551
Author: Julian Brown <julian@codesourcery.com>
Date:   Wed Oct 16 08:28:32 2019 -0700

    [og9] Fix libgomp serial-dims.c test for AMD GCN
    
    	libgomp/
    	* testsuite/libgomp.oacc-c-c++-common/serial-dims.c: Support AMD GCN.
    
    (cherry picked from openacc-gcc-9-branch commit
    195a5318951ab947de00a4372d216ba9536493d3)

Diff:
---
 libgomp/ChangeLog.omp                                     | 4 ++++
 libgomp/testsuite/libgomp.oacc-c-c++-common/serial-dims.c | 7 +++++++
 2 files changed, 11 insertions(+)

diff --git a/libgomp/ChangeLog.omp b/libgomp/ChangeLog.omp
index 2ed7869..bf880ac 100644
--- a/libgomp/ChangeLog.omp
+++ b/libgomp/ChangeLog.omp
@@ -1,3 +1,7 @@
+2019-10-16  Julian Brown  <julian@codesourcery.com>
+
+	* testsuite/libgomp.oacc-c-c++-common/serial-dims.c: Support AMD GCN.
+
 2019-10-09  Tobias Burnus  <tobias@codesourcery.com>
 
 	* testsuite/libgomp.fortran/use_device_ptr1.f90: New.
diff --git a/libgomp/testsuite/libgomp.oacc-c-c++-common/serial-dims.c b/libgomp/testsuite/libgomp.oacc-c-c++-common/serial-dims.c
index 3895405..e373ebd 100644
--- a/libgomp/testsuite/libgomp.oacc-c-c++-common/serial-dims.c
+++ b/libgomp/testsuite/libgomp.oacc-c-c++-common/serial-dims.c
@@ -69,6 +69,13 @@ int main ()
 	  /* The GCC nvptx back end enforces vector_length (32).  */
 	  vectors_actual = 32;
 	}
+      else if (acc_on_device (acc_device_gcn))
+	{
+	  /* AMD GCN relies on the autovectorizer for the vector dimension:
+	     the loop below isn't likely to be vectorized, so vectors_actual
+	     is effectively 1.  */
+	  vectors_actual = 1;
+	}
       else if (!acc_on_device (acc_device_host))
 	__builtin_abort ();
 #pragma acc loop gang \