Make SSE4.1 warning clearer

"Disable SSE4.1" can be misunderstood for a suggestion to set
the acceleration to "None".

Change-Id: If83339c2fedd8dcf47aa4a841128cf08cc369a90

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 89c984d24a32e357a95ee90c716d3f415f366c0f..b9f3dfca9bf8e1ece05cbe3ff160b9c1fecb4945 100644 (file)
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -730,7 +730,7 @@ elseif(${GMX_CPU_ACCELERATION} STREQUAL "SSE4.1")
         GMX_TEST_CFLAG(MSVC_SSE4_CFLAG "/arch:SSE4.1" GROMACS_C_FLAGS)
     endif(NOT GNU_SSE4_CFLAG)
     if (NOT GNU_SSE4_CFLAG AND NOT MSVC_SSE4_CFLAG)
-        message(WARNING "No C SSE4.1 flag found. Consider a newer compiler, or disable SSE4.1 for slightly lower performance.")
+        message(WARNING "No C SSE4.1 flag found. Consider a newer compiler, or use SSE2 for slightly lower performance.")
         # Not surprising if we end up here! MSVC current does not support the SSE4.1 flag. However, it appears to accept SSE4.1
         # intrinsics when SSE2 support is enabled, so we try that instead.
         GMX_TEST_CFLAG(MSVC_SSE2_CFLAG "/arch:SSE2" GROMACS_C_FLAGS)
@@ -742,7 +742,7 @@ elseif(${GMX_CPU_ACCELERATION} STREQUAL "SSE4.1")
             GMX_TEST_CXXFLAG(MSVC_SSE4_CXXFLAG "/arch:SSE4.1" GROMACS_CXX_FLAGS)
         endif(NOT GNU_SSE4_CXXFLAG)
         if (NOT GNU_SSE4_CXXFLAG AND NOT MSVC_SSE4_CXXFLAG) 
-            message(WARNING "No C++ SSE4.1 flag found. Consider a newer compiler, or disable SSE4.1 for slightly lower performance.")
+            message(WARNING "No C++ SSE4.1 flag found. Consider a newer compiler, or use SSE2 for slightly lower performance.")
             # Not surprising if we end up here! MSVC current does not support the SSE4.1 flag. However, it appears to accept SSE4.1
             # intrinsics when SSE2 support is enabled, so we try that instead.
             GMX_TEST_CXXFLAG(MSVC_SSE2_CXXFLAG "/arch:SSE2" GROMACS_CXX_FLAGS)