[glibc/ibm/2.32/master] S390: Also check vector support in memmove ifunc-selector [BZ #27511]

[glibc/ibm/2.32/master] S390: Also check vector support in memmove ifunc-selector [BZ #27511]

[Tulio Magno Quites Machado Filho]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=778b8d37865a1d6689155c23802724bf11e4bc75

commit 778b8d37865a1d6689155c23802724bf11e4bc75
Author: Stefan Liebler <stli@linux.ibm.com>
Date:   Tue Mar 23 17:29:26 2021 +0100

    S390: Also check vector support in memmove ifunc-selector [BZ #27511]
    
    The arch13 memmove variant is currently selected by the ifunc selector
    if the Miscellaneous-Instruction-Extensions Facility 3 facility bit
    is present, but the function is also using vector instructions.
    If the vector support is not present, one is receiving an operation
    exception.
    
    Therefore this patch also checks for vector support in the ifunc
    selector and in ifunc-impl-list.c.
    
    Just to be sure, the configure check is now also testing an arch13
    vector instruction and an arch13 Miscellaneous-Instruction-Extensions
    Facility 3 instruction.
    
    (cherry picked from commit 7759be2593b689cb1eafc0f52ee7f59c639e5d2f)

Diff:
---
 sysdeps/s390/configure                   | 8 ++++++--
 sysdeps/s390/configure.ac                | 8 ++++++--
 sysdeps/s390/memmove.c                   | 2 +-
 sysdeps/s390/multiarch/ifunc-impl-list.c | 3 ++-
 4 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/sysdeps/s390/configure b/sysdeps/s390/configure
index fa46e9e351..e7f576338d 100644
--- a/sysdeps/s390/configure
+++ b/sysdeps/s390/configure
@@ -123,7 +123,9 @@ void testinsn (char *buf)
     __asm__ (".machine \"arch13\" \n\t"
 	     ".machinemode \"zarch_nohighgprs\" \n\t"
 	     "lghi %%r0,16 \n\t"
-	     "mvcrl 0(%0),32(%0)" : : "a" (buf) : "memory", "r0");
+	     "mvcrl 0(%0),32(%0) \n\t"
+	     "vstrs %%v20,%%v20,%%v20,%%v20,0,2"
+	     : : "a" (buf) : "memory", "r0");
 }
 EOF
 if { ac_try='${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS --shared conftest.c
@@ -271,7 +273,9 @@ else
 void testinsn (char *buf)
 {
     __asm__ ("lghi %%r0,16 \n\t"
-	     "mvcrl 0(%0),32(%0)" : : "a" (buf) : "memory", "r0");
+	     "mvcrl 0(%0),32(%0) \n\t"
+	     "vstrs %%v20,%%v20,%%v20,%%v20,0,2"
+	     : : "a" (buf) : "memory", "r0");
 }
 EOF
 if { ac_try='${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS --shared conftest.c
diff --git a/sysdeps/s390/configure.ac b/sysdeps/s390/configure.ac
index 3ed5a8ef87..5c3479e8cf 100644
--- a/sysdeps/s390/configure.ac
+++ b/sysdeps/s390/configure.ac
@@ -88,7 +88,9 @@ void testinsn (char *buf)
     __asm__ (".machine \"arch13\" \n\t"
 	     ".machinemode \"zarch_nohighgprs\" \n\t"
 	     "lghi %%r0,16 \n\t"
-	     "mvcrl 0(%0),32(%0)" : : "a" (buf) : "memory", "r0");
+	     "mvcrl 0(%0),32(%0) \n\t"
+	     "vstrs %%v20,%%v20,%%v20,%%v20,0,2"
+	     : : "a" (buf) : "memory", "r0");
 }
 EOF
 dnl test, if assembler supports S390 arch13 instructions
@@ -195,7 +197,9 @@ cat > conftest.c <<\EOF
 void testinsn (char *buf)
 {
     __asm__ ("lghi %%r0,16 \n\t"
-	     "mvcrl 0(%0),32(%0)" : : "a" (buf) : "memory", "r0");
+	     "mvcrl 0(%0),32(%0) \n\t"
+	     "vstrs %%v20,%%v20,%%v20,%%v20,0,2"
+	     : : "a" (buf) : "memory", "r0");
 }
 EOF
 dnl test, if assembler supports S390 arch13 zarch instructions as default
diff --git a/sysdeps/s390/memmove.c b/sysdeps/s390/memmove.c
index 5fc85e129f..ee59b5de14 100644
--- a/sysdeps/s390/memmove.c
+++ b/sysdeps/s390/memmove.c
@@ -43,7 +43,7 @@ extern __typeof (__redirect_memmove) MEMMOVE_ARCH13 attribute_hidden;
 s390_libc_ifunc_expr (__redirect_memmove, memmove,
 		      ({
 			s390_libc_ifunc_expr_stfle_init ();
-			(HAVE_MEMMOVE_ARCH13
+			(HAVE_MEMMOVE_ARCH13 && (hwcap & HWCAP_S390_VXRS_EXT2)
 			 && S390_IS_ARCH13_MIE3 (stfle_bits))
 			  ? MEMMOVE_ARCH13
 			  : (HAVE_MEMMOVE_Z13 && (hwcap & HWCAP_S390_VX))
diff --git a/sysdeps/s390/multiarch/ifunc-impl-list.c b/sysdeps/s390/multiarch/ifunc-impl-list.c
index e6195c6e26..17c0cc3952 100644
--- a/sysdeps/s390/multiarch/ifunc-impl-list.c
+++ b/sysdeps/s390/multiarch/ifunc-impl-list.c
@@ -171,7 +171,8 @@ __libc_ifunc_impl_list (const char *name, struct libc_ifunc_impl *array,
     IFUNC_IMPL (i, name, memmove,
 # if HAVE_MEMMOVE_ARCH13
 		IFUNC_IMPL_ADD (array, i, memmove,
-				S390_IS_ARCH13_MIE3 (stfle_bits),
+				((dl_hwcap & HWCAP_S390_VXRS_EXT2)
+				 && S390_IS_ARCH13_MIE3 (stfle_bits)),
 				MEMMOVE_ARCH13)
 # endif
 # if HAVE_MEMMOVE_Z13