From: Daniel Arndt <daniel.arndt@iwr.uni-heidelberg.de>
Date: Tue, 29 Jan 2019 22:23:50 +0000 (+0100)
Subject: Disable SIMD vectorization in CUDA device code
X-Git-Tag: v9.1.0-rc1~390^2
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=174fe8cce2d9ec68185227ea190274695160a3f4;p=dealii.git

Disable SIMD vectorization in CUDA device code
---

diff --git a/include/deal.II/base/config.h.in b/include/deal.II/base/config.h.in
index 7801a2397f..9da0d4818f 100644
--- a/include/deal.II/base/config.h.in
+++ b/include/deal.II/base/config.h.in
@@ -114,7 +114,14 @@
  */
 
 #cmakedefine DEAL_II_WORDS_BIGENDIAN
-#define DEAL_II_COMPILER_VECTORIZATION_LEVEL @DEAL_II_COMPILER_VECTORIZATION_LEVEL@
+// We need to disable SIMD vectorization for CUDA device code.
+// Otherwise, nvcc compilers from version 9 on will emit an error message like:
+// "[...] contains a vector, which is not supported in device code"
+#ifdef __CUDA_ARCH__
+#  define DEAL_II_COMPILER_VECTORIZATION_LEVEL 0
+#else
+#  define DEAL_II_COMPILER_VECTORIZATION_LEVEL @DEAL_II_COMPILER_VECTORIZATION_LEVEL@
+#endif
 #define DEAL_II_OPENMP_SIMD_PRAGMA @DEAL_II_OPENMP_SIMD_PRAGMA@