acinclude.m4 (GLIBCXX_ENABLE_ATOMIC_BUILTINS): New.

2006-07-14  Benjamin Kosnik  <bkoz@redhat.com>

        * acinclude.m4 (GLIBCXX_ENABLE_ATOMIC_BUILTINS): New.
        * configure.ac: Use it.
        * configure: Regenerated.	
        * config.h.in: Regenerated.		
        * configure.host: Simplify.
        * include/bits/atomicity.h: Adjust macros.	
        * config/cpu/generic/atomicity.h: Move...
        * config/cpu/generic/atomicity_mutex: New.
        * config/cpu/generic/atomicity_mutex/atomicity.h: ...here.
        * config/cpu/generic/atomic_builtins: Rename...
        * config/cpu/generic/atomicity_builtins: ...to this.
        * config/cpu/generic/atomicity_builtins/atomicity.h: Moved.
	* config/cpu/mips/atomicity.h: Comment MIPS II requirement.

	* scripts/testsuite_flags.in: Make --cxxflags reflect CXXFLAGS.

From-SVN: r115456

libstdc++-v3/ChangeLog

@@ -1,3 +1,21 @@
+2006-07-14  Benjamin Kosnik  <bkoz@redhat.com>
+
+        * acinclude.m4 (GLIBCXX_ENABLE_ATOMIC_BUILTINS): New.
+        * configure.ac: Use it.
+        * configure: Regenerated.	
+        * config.h.in: Regenerated.		
+        * configure.host: Simplify.
+        * include/bits/atomicity.h: Adjust macros.	
+        * config/cpu/generic/atomicity.h: Move...
+        * config/cpu/generic/atomicity_mutex: New.
+        * config/cpu/generic/atomicity_mutex/atomicity.h: ...here.
+        * config/cpu/generic/atomic_builtins: Rename...
+        * config/cpu/generic/atomicity_builtins: ...to this.
+        * config/cpu/generic/atomicity_builtins/atomicity.h: Moved.
+	* config/cpu/mips/atomicity.h: Comment MIPS II requirement.
+
+	* scripts/testsuite_flags.in: Make --cxxflags reflect CXXFLAGS.
+	
 2006-07-14  Paolo Carlini  <pcarlini@suse.de>
 
 	* include/tr1/random (minstd_rand0, minstd_rand, ranlux3, ranlux4):

libstdc++-v3/acinclude.m4

@@ -1966,6 +1966,69 @@ AC_DEFUN([GLIBCXX_ENABLE_PCH], [
 ])
 
 
+dnl
+dnl Check for atomic builtins.
+dnl See:
+dnl http://gcc.gnu.org/onlinedocs/gcc/Atomic-Builtins.html#Atomic-Builtins
+dnl
+dnl This checks to see if the host supports the compiler-generated
+dnl builtins for atomic operations. Note, this is intended to be an
+dnl all-or-nothing switch, so all the atomic operations that are used
+dnl should be checked.
+dnl
+dnl Note:
+dnl libgomp and libgfortran do this with a link test, instead of an asm test.
+dnl see: CHECK_SYNC_FETCH_AND_ADD
+dnl
+dnl Defines:
+dnl  _GLIBCXX_ATOMIC_BUILTINS if the compiler on this target supports atomics.
+dnl
+AC_DEFUN([GLIBCXX_ENABLE_ATOMIC_BUILTINS], [
+  AC_MSG_CHECKING([for atomic builtins])
+  AC_LANG_SAVE
+  AC_LANG_CPLUSPLUS
+
+  # Fake what AC_TRY_COMPILE does.  XXX Look at redoing this new-style.
+    cat > conftest.$ac_ext << EOF
+[#]line __oline__ "configure"
+int main()
+{
+  // NB: _Atomic_word not necessarily int. 
+  typedef int atomic_type;
+  atomic_type c1;
+  atomic_type c2;
+  const atomic_type c3(0);
+  if (__sync_fetch_and_add(&c1, c2) == c3)
+    {
+      // Do something.
+    }
+   return 0;
+}
+EOF
+    old_CXXFLAGS="$CXXFLAGS"
+    CXXFLAGS="$CXXFLAGS -S"
+    if AC_TRY_EVAL(ac_compile); then
+      if grep __sync_fetch_and_add conftest.s >/dev/null 2>&1 ; then
+        enable_atomic_builtins=no
+      else
+      AC_DEFINE(_GLIBCXX_ATOMIC_BUILTINS, 1,
+        [Define if builtin atomic operations are supported on this host.])
+        enable_atomic_builtins=yes
+	atomicity_dir=cpu/generic/atomicity_builtins
+      fi
+    fi
+    CXXFLAGS="$old_CXXFLAGS"
+    rm -f conftest*
+
+   # Now, if still generic, set to mutex.
+  if test $atomicity_dir = "cpu/generic" ; then
+	atomicity_dir=cpu/generic/atomicity_mutex
+  fi
+ AC_LANG_RESTORE
+ AC_MSG_RESULT($enable_atomic_builtins)
+])
+
+
 dnl
 dnl Check for exception handling support.  If an explicit enable/disable
 dnl sjlj exceptions is given, we don't have to detect.  Otherwise the

libstdc++-v3/config.h.in

@@ -655,7 +655,7 @@
 /* Version number of package */
 #undef VERSION
 
-/* Define if atomic builtins are provided for this platform. */
+/* Define if builtin atomic operations are supported on this host. */
 #undef _GLIBCXX_ATOMIC_BUILTINS
 
 /* Define to use concept checking code from the boost libraries. */

libstdc++-v3/config/cpu/generic/atomicity_builtins/atomicity.h

@@ -28,10 +28,13 @@
 // invalidate any other reasons why the executable file might be covered by
 // the GNU General Public License.
 
-#include <bits/atomicity.h>
+#include <bits/c++config.h>
+#include <bits/atomic_word.h>
 
 _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
 
+  // XXX GLIBCXX_ABI Deprecated
+  // Should be inlined, and not exported.
   _Atomic_word 
   __attribute__ ((__unused__))
   __exchange_and_add(volatile _Atomic_word* __mem, int __val)

libstdc++-v3/config/cpu/mips/atomicity.h

@@ -1,6 +1,7 @@
 // Low-level functions for atomic operations: MIPS version  -*- C++ -*-
 
-// Copyright (C) 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
+// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006
+// Free Software Foundation, Inc.
 //
 // This file is part of the GNU ISO C++ Library.  This library is free
 // software; you can redistribute it and/or modify it under the
@@ -31,6 +32,7 @@
 
 _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
 
+  // NB: MIPS II or above required.
   _Atomic_word
   __attribute__ ((__unused__))
   __exchange_and_add(volatile _Atomic_word* __mem, int __val)

libstdc++-v3/configure

@@ -7994,7 +7994,71 @@ _ACEOF
 
 
 
-if test $atomicity_dir = cpu/generic ; then
+
+  echo "$as_me:$LINENO: checking for atomic builtins" >&5
+echo $ECHO_N "checking for atomic builtins... $ECHO_C" >&6
+
+
+  ac_ext=cc
+ac_cpp='$CXXCPP $CPPFLAGS'
+ac_compile='$CXX -c $CXXFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CXX -o conftest$ac_exeext $CXXFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_cxx_compiler_gnu
+
+
+  # Fake what AC_TRY_COMPILE does.  XXX Look at redoing this new-style.
+    cat > conftest.$ac_ext << EOF
+#line 8011 "configure"
+int main()
+{
+  // NB: _Atomic_word not necessarily int.
+  typedef int atomic_type;
+  atomic_type c1;
+  atomic_type c2;
+  const atomic_type c3(0);
+  if (__sync_fetch_and_add(&c1, c2) == c3)
+    {
+      // Do something.
+    }
+   return 0;
+}
+EOF
+    old_CXXFLAGS="$CXXFLAGS"
+    CXXFLAGS="$CXXFLAGS -S"
+    if { (eval echo "$as_me:$LINENO: \"$ac_compile\"") >&5
+  (eval $ac_compile) 2>&5
+  ac_status=$?
+  echo "$as_me:$LINENO: \$? = $ac_status" >&5
+  (exit $ac_status); }; then
+      if grep __sync_fetch_and_add conftest.s >/dev/null 2>&1 ; then
+        enable_atomic_builtins=no
+      else
+
+cat >>confdefs.h <<\_ACEOF
+#define _GLIBCXX_ATOMIC_BUILTINS 1
+_ACEOF
+
+        enable_atomic_builtins=yes
+	atomicity_dir=cpu/generic/atomicity_builtins
+      fi
+    fi
+    CXXFLAGS="$old_CXXFLAGS"
+    rm -f conftest*
+
+   # Now, if still generic, set to mutex.
+  if test $atomicity_dir = "cpu/generic" ; then
+	atomicity_dir=cpu/generic/atomicity_mutex
+  fi
+ ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+ echo "$as_me:$LINENO: result: $enable_atomic_builtins" >&5
+echo "${ECHO_T}$enable_atomic_builtins" >&6
+
+if test $atomicity_dir = cpu/generic/atomic_mutex ; then
   { echo "$as_me:$LINENO: WARNING: No native atomic operations are provided for this platform." >&5
 echo "$as_me: WARNING: No native atomic operations are provided for this platform." >&2;}
   if test $target_thread_file = single; then
@@ -109919,14 +109983,6 @@ ABI_TWEAKS_SRCDIR=config/${abi_tweaks_dir}
 
 
 
-# Atomic builtins can be inlined in bits/atomicity.h.
-if test $atomicity_dir = cpu/generic/atomic_builtins ; then
-
-cat >>confdefs.h <<\_ACEOF
-#define _GLIBCXX_ATOMIC_BUILTINS 1
-_ACEOF
-
-fi
 
 # Determine cross-compile flags and AM_CONDITIONALs.
 #AC_SUBST(GLIBCXX_IS_NATIVE)

libstdc++-v3/configure.ac

@@ -112,7 +112,8 @@ GLIBCXX_ENABLE_FULLY_DYNAMIC_STRING([no])
 
 # No surprises, no surprises...
 GLIBCXX_ENABLE_THREADS
-if test $atomicity_dir = cpu/generic ; then
+GLIBCXX_ENABLE_ATOMIC_BUILTINS
+if test $atomicity_dir = cpu/generic/atomic_mutex ; then
   AC_MSG_WARN([No native atomic operations are provided for this platform.])
   if test $target_thread_file = single; then
     AC_MSG_WARN([They cannot be faked when thread support is disabled.])
@@ -321,11 +322,6 @@ AC_SUBST(CPU_DEFINES_SRCDIR)
 AC_SUBST(ABI_TWEAKS_SRCDIR)
 AC_SUBST(OS_INC_SRCDIR)
 
-# Atomic builtins can be inlined in bits/atomicity.h.
-if test $atomicity_dir = cpu/generic/atomic_builtins ; then
-  AC_DEFINE([_GLIBCXX_ATOMIC_BUILTINS], 1,
-            [Define if atomic builtins are provided for this platform.])
-fi
 
 # Determine cross-compile flags and AM_CONDITIONALs.
 #AC_SUBST(GLIBCXX_IS_NATIVE)

libstdc++-v3/configure.host

@@ -67,13 +67,16 @@
 c_model=c_std
 c_compatibility=no
 atomic_word_dir=cpu/generic
-cpu_defines_dir=cpu/generic
+atomicity_dir="cpu/generic"
+cpu_defines_dir="cpu/generic"
+try_cpu=generic
+abi_tweaks_dir="cpu/generic"
 
 # HOST-SPECIFIC OVERRIDES
 # Set any CPU-dependent bits.
-# Here we override defaults and catch more general cases due to naming
-# conventions (e.g., chip_name* to catch all variants).
 
+# Provide a way to funnel exotic flavors and prefixed/postfixed chip
+# variants into the established source config/cpu/* sub-directories.
 # THIS TABLE IS SORTED.  KEEP IT THAT WAY.
 case "${host_cpu}" in
   alpha*)
@@ -89,11 +92,7 @@ case "${host_cpu}" in
     try_cpu=hppa
     ;;
   mips*)
-    # NB: cpu/mips/atomicity.h needs MIPS II or above.  
+    try_cpu=mips
-    # Of course, there is no sane way to test for this, no ABI macro,
-    # and no consistent host_cpu name differentiation. Therefore, only
-    # use it where it is known to be safe, ie it runs linux (see below).
-    try_cpu=generic
     ;;
   m680[246]0)
     try_cpu=m68k
@@ -101,31 +100,21 @@ case "${host_cpu}" in
   powerpc* | rs6000)
     try_cpu=powerpc
     ;;
-  s390x)
-    try_cpu=s390
-    ;;
   sparc* | ultrasparc)
     try_cpu=sparc
     ;;
   *)
     if test -d ${glibcxx_srcdir}/config/cpu/${host_cpu}; then
       try_cpu=${host_cpu}
-    else
-      try_cpu=generic
     fi
-    ;;
 esac
 
-# Set specific CPU overrides for atomic_word_dir. Most can just use generic.
+
-# THIS TABLE IS SORTED.  KEEP IT THAT WAY.
+# Now look for the file(s) usually tied to a CPU model, and make
-case "${host_cpu}" in
+# default choices for those if they haven't been explicitly set
-  cris*)
+# already.  
-    atomic_word_dir=cpu/cris
+cpu_include_dir=cpu/${try_cpu}
-    ;;
+
-  sparc* | ultrasparc)
-    atomic_word_dir=cpu/sparc
-    ;;
-esac
 
 # Set specific CPU overrides for cpu_defines_dir. Most can just use generic.
 # THIS TABLE IS SORTED.  KEEP IT THAT WAY.
@@ -135,32 +124,41 @@ case "${host_cpu}" in
     ;;
 esac
 
-# Now look for the file(s) usually tied to a CPU model, and make
-# default choices for those if they haven't been explicitly set
-# already.  
-cpu_include_dir=cpu/${try_cpu}
-abi_baseline_pair=${try_cpu}-${host_os}
-unset try_cpu
 
+# Set specific CPU overrides for atomic_word_dir. Most can just use generic.
+# THIS TABLE IS SORTED.  KEEP IT THAT WAY.
 case "${host_cpu}" in
-  alpha* | ia64 | powerpc* | rs6000 | s390*)
+  alpha*)
-    atomicity_dir="cpu/generic/atomic_builtins"
+    atomic_word_dir=cpu/alpha
     ;;
-  *)
+  cris*)
-    if test -f ${glibcxx_srcdir}/config/${cpu_include_dir}/atomicity.h ; then
+    atomic_word_dir=cpu/cris
-      atomicity_dir=$cpu_include_dir
+    ;;
-    else
+  ia64)
-      atomicity_dir="cpu/generic"
+    atomic_word_dir=cpu/ia64
-    fi
+    ;;
+  powerpc* | rs6000)
+    atomic_word_dir=cpu/powerpc
+    ;;
+  sparc* | ultrasparc)
+    atomic_word_dir=cpu/sparc
     ;;
 esac
 
+
+# Set specific CPU overrides for atomicity_dir.
+# This can be over-ridden in GLIBCXX_ENABLE_ATOMIC_BUILTINS.
+# THIS TABLE IS SORTED.  KEEP IT THAT WAY.
+if test -f ${glibcxx_srcdir}/config/${cpu_include_dir}/atomicity.h ; then
+  atomicity_dir=$cpu_include_dir
+fi
+
+
 if test -f ${glibcxx_srcdir}/config/${cpu_include_dir}/cxxabi_tweaks.h ; then
   abi_tweaks_dir=$cpu_include_dir
-else
-  abi_tweaks_dir="cpu/generic"
 fi
 
+
 # Set any OS-dependent bits.
 # Set the os_include_dir.
 # Set c_model, c_compatibility here.
@@ -276,39 +274,39 @@ esac
 # Set any OS-dependent and CPU-dependent bits.
 # THIS TABLE IS SORTED.  KEEP IT THAT WAY.
 case "${host}" in
-  alpha*-*-freebsd5*)
+  *-*-linux*)
-    abi_baseline_pair="alpha-freebsd5"
+    case "${host_cpu}" in
+      i[567]86)
+        abi_baseline_pair=i486-linux-gnu
+        ;;
+      powerpc64)
+        abi_baseline_pair=powerpc64-linux-gnu
+        ;;
+      s390)
+        abi_baseline_pair=s390-linux-gnu
+        ;;
+      s390x)
+        abi_baseline_pair=s390x-linux-gnu
+        ;;
+      x86_64)
+        abi_baseline_pair=x86_64-linux-gnu
+        ;;
+      *)
+        if test -d ${glibcxx_srcdir}/config/abi/post/${try_cpu}-linux-gnu; then
+          abi_baseline_pair=${try_cpu}-linux-gnu
+        fi
+    esac
     ;;
-  arm*-*-linux*)
+  mips*-*-*)
-    abi_baseline_pair="arm-linux-gnu"
+    case "${host_os}" in
-    ;;
+      gnu* | linux* | irix*)
-  i*86-*-freebsd4*)
+        ;;
-    abi_baseline_pair="i386-freebsd4"
+      *)
-    ;;
+        atomicity_dir="cpu/generic"
-  i*86-*-freebsd5*)
+        ;;
-    abi_baseline_pair="i386-freebsd5"
+    esac
-    ;;
-  mips*-*-linux*)
-    atomicity_dir="cpu/mips"
-    abi_baseline_pair="mips-linux-gnu"
-    cpu_include_dir="cpu/mips"
     ;;
   powerpc*-*-darwin*)
     port_specific_symbol_files="\$(srcdir)/../config/os/bsd/darwin/ppc-extra.ver"
     ;;
-  powerpc64-*-linux*)
-    abi_baseline_pair="powerpc64-linux-gnu"
-    ;;
-  s390-*-linux*)
-    abi_baseline_pair="s390-linux-gnu"
-    ;;
-  s390x-*-linux*)
-    abi_baseline_pair="s390x-linux-gnu"
-    ;;
-  sparc*-*-freebsd5*)
-    abi_baseline_pair="sparc-freebsd5"
-    ;;
-  x86_64-*-linux*)
-    abi_baseline_pair="x86_64-linux-gnu"
-    ;;
 esac

libstdc++-v3/include/bits/atomicity.h

@@ -41,6 +41,15 @@
 
 _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
 
+#ifdef _GLIBCXX_ATOMIC_BUILTINS
+  static inline _Atomic_word 
+  __exchange_and_add(volatile _Atomic_word* __mem, int __val)
+  { return __sync_fetch_and_add(__mem, __val); }
+
+  static inline void
+  __atomic_add(volatile _Atomic_word* __mem, int __val)
+  { __sync_fetch_and_add(__mem, __val); }
+#else
   _Atomic_word
   __attribute__ ((__unused__))
   __exchange_and_add(volatile _Atomic_word* __mem, int __val);
@@ -48,34 +57,7 @@ _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
   void
   __attribute__ ((__unused__))
   __atomic_add(volatile _Atomic_word* __mem, int __val);
-
-  static inline _Atomic_word
-  __exchange_and_add_multi(volatile _Atomic_word* __mem, int __val)
-  {
-#ifdef _GLIBCXX_ATOMIC_BUILTINS
-
-    return __sync_fetch_and_add(__mem, __val);
-
-#else
-
-    return __exchange_and_add(__mem, __val);
-
 #endif
-  }
-
-  static inline void
-  __atomic_add_multi(volatile _Atomic_word* __mem, int __val)
-  { 
-#ifdef _GLIBCXX_ATOMIC_BUILTINS
-
-    __sync_fetch_and_add(__mem, __val);
-
-#else
-
-    __atomic_add(__mem, __val);
-
-#endif
-  }
 
   static inline _Atomic_word
   __exchange_and_add_single(volatile _Atomic_word* __mem, int __val)
@@ -94,16 +76,12 @@ _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
   __exchange_and_add_dispatch(volatile _Atomic_word* __mem, int __val)
   {
 #ifdef __GTHREADS
-
     if (__gthread_active_p())
-      return __exchange_and_add_multi(__mem, __val);
+      return __exchange_and_add(__mem, __val);
     else
       return __exchange_and_add_single(__mem, __val);
-
 #else
-
     return __exchange_and_add_single(__mem, __val);
-
 #endif
   }
 
@@ -112,23 +90,19 @@ _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
   __atomic_add_dispatch(volatile _Atomic_word* __mem, int __val)
   {
 #ifdef __GTHREADS
-
     if (__gthread_active_p())
-      __atomic_add_multi(__mem, __val);
+      __atomic_add(__mem, __val);
     else
       __atomic_add_single(__mem, __val);
-
 #else
-
     __atomic_add_single(__mem, __val);
-
 #endif
   }
 
 _GLIBCXX_END_NAMESPACE
 
-/* Even if the CPU doesn't need a memory barrier, we need to ensure that
+// Even if the CPU doesn't need a memory barrier, we need to ensure that
-   the compiler doesn't reorder memory accesses across the barriers.  */
+// the compiler doesn't reorder memory accesses across the barriers.
 #ifndef _GLIBCXX_READ_MEM_BARRIER
 #define _GLIBCXX_READ_MEM_BARRIER __asm __volatile ("":::"memory")
 #endif

libstdc++-v3/scripts/testsuite_flags.in

@@ -50,7 +50,7 @@ case ${query} in
     --cxxflags)
       CXXFLAGS_save="-g -O2 -D_GLIBCXX_ASSERT"
       CXXFLAGS_config='@SECTION_FLAGS@ -fmessage-length=0 
- 		      @EXTRA_CXX_FLAGS@ '
+ 		      @CXXFLAGS@ @EXTRA_CXX_FLAGS@ '
       echo ${CXXFLAGS_save} ${CXXFLAGS_config}
       ;;
     --cxxpchflags)