From: Dan Mick <dan.mick@redhat.com>
Date: Sat, 25 Mar 2017 03:12:38 +0000 (-0700)
Subject: cmake/modules/SIMDExt.cmake: armv8 crypto intrinsics
X-Git-Tag: v12.0.2~297^2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=refs%2Fpull%2F14132%2Fhead;p=ceph.git

cmake/modules/SIMDExt.cmake: armv8 crypto intrinsics

Test not only for -march support, but also the actual
presence of the intrinsic routines.  Not sure why, but gcc
4.8.5 passes the first but not the second.

Fixes: http://tracker.ceph.com/issues/19386
Signed-off-by: Dan Mick <dan.mick@redhat.com>
---

diff --git a/cmake/modules/SIMDExt.cmake b/cmake/modules/SIMDExt.cmake
index badb94adb4bc..bcc492f3af06 100644
--- a/cmake/modules/SIMDExt.cmake
+++ b/cmake/modules/SIMDExt.cmake
@@ -44,7 +44,18 @@ if(CMAKE_SYSTEM_PROCESSOR MATCHES "aarch64|AARCH64")
   if(HAVE_ARMV8_CRYPTO)
     message(STATUS " aarch64 crypto extensions supported")
   endif()
-  CHECK_C_COMPILER_FLAG(-march=armv8-a+crc+crypto HAVE_ARMV8_CRC_CRYPTO_INTRINSICS)
+  CHECK_C_COMPILER_FLAG(-march=armv8-a+crc+crypto HAVE_ARMV8_CRC_CRYPTO_MARCH)
+
+  # don't believe only the -march support; gcc 4.8.5 on RHEL/CentOS says
+  # it supports +crc but hasn't got the intrinsics or arm_acle.h.  Test for
+  # the actual presence of one of the intrinsic functions.
+  if(HAVE_ARMV8_CRC_CRYPTO_MARCH)
+    check_cxx_source_compiles("
+      #include <inttypes.h>
+      int main() { uint32_t a; uint8_t b; __builtin_aarch64_crc32b(a, b); }
+    " HAVE_ARMV8_CRC_CRYPTO_INTRINSICS)
+  endif()
+
   if(HAVE_ARMV8_CRC_CRYPTO_INTRINSICS)
     message(STATUS " aarch64 crc+crypto intrinsics supported")
     set(ARMV8_CRC_COMPILE_FLAGS "${ARMV8_CRC_COMPILE_FLAGS} -march=armv8-a+crc+crypto")