From 3ca6351daa2a4e90af9a97085f8fa316b6ede57f Mon Sep 17 00:00:00 2001
From: Ulrich Drepper <drepper@gmail.com>
Date: Sun, 9 Sep 2012 17:20:42 +0000
Subject: [PATCH] re PR bootstrap/54419 (Compiling
libstdc++-v3/src/c++11/random.cc fails on platforms not knowing rdrand)
2012-09-09 Ulrich Drepper <drepper@gmail.com>
Dominique d'Humieres <dominiq@lps.ens.fr>
Jack Howarth <howarth@bromo.med.uc.edu>
PR bootstrap/54419
* acinclude.m4: Define GLIBCXX_CHECK_X86_RDRAND.
* configure.ac: Use GLIBCXX_CHECK_X86_RDRAND to test for rdrand
support in assembler.
* src/c++11/random.cc (__x86_rdrand): Depend on _GLIBCXX_X86_RDRAND.
(random_device::_M_init): Likewise.
(random_device::_M_getval): Likewise.
* configure: Regenerated.
* config.h.in: Regenerated.
Co-Authored-By: Dominique d'Humieres <dominiq@lps.ens.fr>
Co-Authored-By: Jack Howarth <howarth@bromo.med.uc.edu>
From-SVN: r191111
---
libstdc++-v3/ChangeLog | 14 +++++++++++
libstdc++-v3/acinclude.m4 | 20 +++++++++++++++
libstdc++-v3/config.h.in | 3 +++
libstdc++-v3/configure | 42 ++++++++++++++++++++++++++++++++
libstdc++-v3/configure.ac | 3 +++
libstdc++-v3/src/c++11/random.cc | 6 ++---
6 files changed, 85 insertions(+), 3 deletions(-)
diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index bd87deca5b34..34a9d76db1da 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,17 @@
+2012-09-09 Ulrich Drepper <drepper@gmail.com>
+ Dominique d'Humieres <dominiq@lps.ens.fr>
+ Jack Howarth <howarth@bromo.med.uc.edu>
+
+ PR bootstrap/54419
+ * acinclude.m4: Define GLIBCXX_CHECK_X86_RDRAND.
+ * configure.ac: Use GLIBCXX_CHECK_X86_RDRAND to test for rdrand
+ support in assembler.
+ * src/c++11/random.cc (__x86_rdrand): Depend on _GLIBCXX_X86_RDRAND.
+ (random_device::_M_init): Likewise.
+ (random_device::_M_getval): Likewise.
+ * configure: Regenerated.
+ * config.h.in: Regenerated.
+
2012-09-09 Ulrich Drepper <drepper@gmail.com>
* src/c++11/random.cc (random_device::_M_init): Use new macro
diff --git a/libstdc++-v3/acinclude.m4 b/libstdc++-v3/acinclude.m4
index 1179407bf551..267302df660c 100644
--- a/libstdc++-v3/acinclude.m4
+++ b/libstdc++-v3/acinclude.m4
@@ -3359,6 +3359,26 @@ AC_DEFUN([AC_LC_MESSAGES], [
])
])
+dnl
+dnl Check whether rdrand is supported in the assembler.
+AC_DEFUN([GLIBCXX_CHECK_X86_RDRAND], [
+ AC_MSG_CHECKING([for rdrand support in assembler])
+ AC_CACHE_VAL($ac_cv_x86_rdrand, [
+ ac_cv_x86_rdrand=no
+ case "$target" in
+ i?86-*-* | \
+ x86_64-*-*)
+ AC_TRY_COMPILE(, [asm("rdrand %eax");],
+ [ac_cv_x86_rdrand=yes], [ac_cv_x86_rdrand=no])
+ esac
+ ])
+ if test $ac_cv_x86_rdrand = yes; then
+ AC_DEFINE(_GLIBCXX_X86_RDRAND, 1,
+ [ Defined if as can handle rdrand. ])
+ fi
+ AC_MSG_RESULT($ac_cv_x86_rdrand)
+])
+
dnl
dnl Check whether get_nprocs is available in <sys/sysinfo.h>, and define _GLIBCXX_USE_GET_NPROCS.
dnl
diff --git a/libstdc++-v3/config.h.in b/libstdc++-v3/config.h.in
index 3a299677dbf9..075c9f814a8d 100644
--- a/libstdc++-v3/config.h.in
+++ b/libstdc++-v3/config.h.in
@@ -845,6 +845,9 @@
/* Define if code specialized for wchar_t should be used. */
#undef _GLIBCXX_USE_WCHAR_T
+/* Defined if as can handle rdrand. */
+#undef _GLIBCXX_X86_RDRAND
+
/* Define to 1 if mutex_timedlock is available. */
#undef _GTHREAD_USE_MUTEX_TIMEDLOCK
diff --git a/libstdc++-v3/configure b/libstdc++-v3/configure
index 9ea8042a1ca9..d55a9efa0b15 100755
--- a/libstdc++-v3/configure
+++ b/libstdc++-v3/configure
@@ -70621,6 +70621,48 @@ $as_echo "#define _GLIBCXX_LONG_DOUBLE_COMPAT 1" >>confdefs.h
esac
+# Check if assembler supports rdrand opcode.
+
+ { $as_echo "$as_me:${as_lineno-$LINENO}: checking for rdrand support in assembler" >&5
+$as_echo_n "checking for rdrand support in assembler... " >&6; }
+ if { as_var=$ac_cv_x86_rdrand; eval "test \"\${$as_var+set}\" = set"; }; then :
+ $as_echo_n "(cached) " >&6
+else
+
+ ac_cv_x86_rdrand=no
+ case "$target" in
+ i?86-*-* | \
+ x86_64-*-*)
+ cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h. */
+
+int
+main ()
+{
+asm("rdrand %eax");
+ ;
+ return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+ ac_cv_x86_rdrand=yes
+else
+ ac_cv_x86_rdrand=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+ esac
+
+fi
+
+ if test $ac_cv_x86_rdrand = yes; then
+
+$as_echo "#define _GLIBCXX_X86_RDRAND 1" >>confdefs.h
+
+ fi
+ { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_x86_rdrand" >&5
+$as_echo "$ac_cv_x86_rdrand" >&6; }
+
+
# This depends on GLIBCXX_ENABLE_SYMVERS and GLIBCXX_IS_NATIVE.
if $GLIBCXX_IS_NATIVE ; then
diff --git a/libstdc++-v3/configure.ac b/libstdc++-v3/configure.ac
index 5c86bb975898..555f380495bc 100644
--- a/libstdc++-v3/configure.ac
+++ b/libstdc++-v3/configure.ac
@@ -330,6 +330,9 @@ case "$target" in
esac
GLIBCXX_CONDITIONAL(GLIBCXX_LDBL_COMPAT, test $ac_ldbl_compat = yes)
+# Check if assembler supports rdrand opcode.
+GLIBCXX_CHECK_X86_RDRAND
+
# This depends on GLIBCXX_ENABLE_SYMVERS and GLIBCXX_IS_NATIVE.
GLIBCXX_CONFIGURE_TESTSUITE
diff --git a/libstdc++-v3/src/c++11/random.cc b/libstdc++-v3/src/c++11/random.cc
index 3b05318ea4cf..4342df4d5468 100644
--- a/libstdc++-v3/src/c++11/random.cc
+++ b/libstdc++-v3/src/c++11/random.cc
@@ -50,7 +50,7 @@ namespace std _GLIBCXX_VISIBILITY(default)
return __ret;
}
-#if defined __i386__ || defined __x86_64__
+#if (defined __i386__ || defined __x86_64__) && defined _GLIBCXX_X86_RDRAND
unsigned int
__attribute__ ((target("rdrnd")))
__x86_rdrand(void)
@@ -75,7 +75,7 @@ namespace std _GLIBCXX_VISIBILITY(default)
if (token == "default")
{
-#if defined __i386__ || defined __x86_64__
+#if (defined __i386__ || defined __x86_64__) && defined _GLIBCXX_X86_RDRAND
unsigned int eax, ebx, ecx, edx;
// Check availability of cpuid and, for now at least, also the
// CPU signature for Intel's
@@ -118,7 +118,7 @@ namespace std _GLIBCXX_VISIBILITY(default)
random_device::result_type
random_device::_M_getval()
{
-#if (defined __i386__ || defined __x86_64__)
+#if (defined __i386__ || defined __x86_64__) && defined _GLIBCXX_X86_RDRAND
if (! _M_file)
return __x86_rdrand();
#endif
--
GitLab