From 29f8926b153d59ba18f67ce5445dce66bacc0cbf Mon Sep 17 00:00:00 2001
From: Stefan Liebler <stli@linux.vnet.ibm.com>
Date: Mon, 7 Nov 2016 15:25:04 +0100
Subject: [PATCH 02/17] S390: Configure check for vector support in gcc.

Upstream commit 9b7f05599a92dead97d6683bc838a57bc63ac52b

The S390 specific test checks if the gcc has support for vector registers
by compiling an inline assembly which clobbers vector registers.
On success the macro HAVE_S390_VX_GCC_SUPPORT is defined.
This macro can be used to determine if e.g. clobbering vector registers
is allowed or not.

ChangeLog:

	* config.h.in (HAVE_S390_VX_GCC_SUPPORT): New macro undefine.
	* sysdeps/s390/configure.in: Add test for S390 vector register
	support in gcc.
	* sysdeps/s390/configure: Regenerated.
---
 config.h.in               |  4 ++++
 sysdeps/s390/configure    | 33 +++++++++++++++++++++++++++++++++
 sysdeps/s390/configure.in | 22 ++++++++++++++++++++++
 3 files changed, 59 insertions(+)

diff --git a/config.h.in b/config.h.in
index f7f2388..62e04c7 100644
--- a/config.h.in
+++ b/config.h.in
@@ -113,6 +113,10 @@
 /* Define if assembler supports vector instructions on S390.  */
 #undef  HAVE_S390_VX_ASM_SUPPORT
 
+/* Define if gcc supports vector registers as clobbers in inline assembly
+   on S390.  */
+#undef  HAVE_S390_VX_GCC_SUPPORT
+
 /* Define if gcc supports FMA4.  */
 #undef	HAVE_FMA4_SUPPORT
 
diff --git a/sysdeps/s390/configure b/sysdeps/s390/configure
index cc4c1e0..eb49a4c 100644
--- a/sysdeps/s390/configure
+++ b/sysdeps/s390/configure
@@ -42,3 +42,36 @@ else
   { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: Use binutils with vector-support in order to use optimized implementations." >&5
 $as_echo "$as_me: WARNING: Use binutils with vector-support in order to use optimized implementations." >&2;}
 fi
+
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for S390 vector support in gcc" >&5
+$as_echo_n "checking for S390 vector support in gcc... " >&6; }
+if ${libc_cv_gcc_s390_vx+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  cat > conftest.c <<\EOF
+void testvecclobber ()
+{
+  __asm__ ("" : : : "v16");
+}
+EOF
+if { ac_try='${CC-cc} --shared conftest.c -o conftest.o &> /dev/null'
+  { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }; } ;
+then
+  libc_cv_gcc_s390_vx=yes
+else
+  libc_cv_gcc_s390_vx=no
+fi
+rm -f conftest*
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_gcc_s390_vx" >&5
+$as_echo "$libc_cv_gcc_s390_vx" >&6; }
+
+if test "$libc_cv_gcc_s390_vx" = yes ;
+then
+  $as_echo "#define HAVE_S390_VX_GCC_SUPPORT 1" >>confdefs.h
+
+fi
diff --git a/sysdeps/s390/configure.in b/sysdeps/s390/configure.in
index 733e356..a3b1f25 100644
--- a/sysdeps/s390/configure.in
+++ b/sysdeps/s390/configure.in
@@ -31,3 +31,25 @@ then
 else
   AC_MSG_WARN([Use binutils with vector-support in order to use optimized implementations.])
 fi
+
+AC_CACHE_CHECK(for S390 vector support in gcc, libc_cv_gcc_s390_vx, [dnl
+cat > conftest.c <<\EOF
+void testvecclobber ()
+{
+  __asm__ ("" : : : "v16");
+}
+EOF
+dnl
+dnl test, if gcc supports S390 vector registers as clobber in inline assembly
+if AC_TRY_COMMAND([${CC-cc} --shared conftest.c -o conftest.o &> /dev/null]) ;
+then
+  libc_cv_gcc_s390_vx=yes
+else
+  libc_cv_gcc_s390_vx=no
+fi
+rm -f conftest* ])
+
+if test "$libc_cv_gcc_s390_vx" = yes ;
+then
+  AC_DEFINE(HAVE_S390_VX_GCC_SUPPORT)
+fi
-- 
1.8.3.1