From 1a3f484051d1531971cd58cb410ef26f4d89b4f5 Mon Sep 17 00:00:00 2001
From: William Brown <firstyear@redhat.com>
Date: Apr 21 2017 13:07:09 +0000
Subject: Ticket 49228 - Fix SSE4.2 detection.


Bug Description:  We incorrectly detect sse4.2 on some platforms.

Fix Description:  Instead of detecting this, we allow GCC to define
the feature flag when possible. At this time, we only use sse4.2
for verification during tests. RPMS build with -mtune=generic, which
will disable sse4.2, so anyone who wants "fast" test execution
(ie a developer) should set -march=native in their cflags.

https://pagure.io/389-ds-base/issue/49228

Author: wibrown

Review by: mreynolds

Signed-off-by: Mark Reynolds <mreynolds@redhat.com>

---

diff --git a/configure.ac b/configure.ac
index 710c0ba..7b9f175 100644
--- a/configure.ac
+++ b/configure.ac
@@ -654,21 +654,9 @@ dnl Cstd and Crun are required to link any C++ related code
     ;;
 esac
 
-AC_MSG_CHECKING([for SSE4.2 features ...])
-save_CFLAGS="$CFLAGS"
-CFLAGS="$CFLAGS -msse4.2"
-AC_TRY_COMPILE(
-    [],
-    [return 0;],
-    [
-        AC_DEFINE([HAVE_SSE4_2], [1], [Have sss4.2 on this platform arch])
-        AC_MSG_RESULT([SSE4.2 avaliable on this platform])
-    ],
-    [
-        AC_MSG_RESULT([SSE4.2 not avaliable on this platform])
-    ]
-)
-CFLAGS="$save_CFLAGS"
+### TO CHECK FOR SSE4.2!!!
+# gcc -march=native -dM -E - < /dev/null | grep SSE
+# We can just use the define in GCC instead!
 
 AC_MSG_CHECKING([for GCC provided 64-bit atomic operations])
 AC_LINK_IFELSE([AC_LANG_PROGRAM([[
diff --git a/src/libsds/sds/core/crc32c.c b/src/libsds/sds/core/crc32c.c
index 8388a61..e4465c3 100644
--- a/src/libsds/sds/core/crc32c.c
+++ b/src/libsds/sds/core/crc32c.c
@@ -15,7 +15,7 @@
 #include <stdlib.h>
 #include <stdio.h>
 
-#ifdef HAVE_SSE4_2
+#ifdef __SSE4_2__
 
 #if CPU_x86_64
 #define REX_PRE "0x48, "
@@ -146,5 +146,5 @@ sds_crc32c(uint32_t crc, const unsigned char *data, size_t length)
     return crc;
 }
 
-#endif
+#endif /* __SSE4_2__ */
 
diff --git a/src/libsds/test/test_sds.c b/src/libsds/test/test_sds.c
index 0d29f22..aff49d0 100644
--- a/src/libsds/test/test_sds.c
+++ b/src/libsds/test/test_sds.c
@@ -12,14 +12,12 @@
 int
 main ( int argc __attribute__((unused)), char **argv __attribute__((unused))) {
     int result = 0;
-    /*
     result += run_bpt_tests();
     result += run_set_tests();
     result += run_cow_tests();
     result += run_queue_tests();
     result += run_tqueue_tests();
     result += run_lqueue_tests();
-    */
     result += run_siphash_tests();
     result += run_ht_tests();
     return result;