gcc: Add 'mcf' thread model support from mcfgthread

This patch adds the new thread model `mcf`, which implements mutexes
and condition variables with the mcfgthread library.

Source code for mcfgthread is available at <https://github.com/lhmouse/mcfgthread>.

config/ChangeLog:
	* gthr.m4 (GCC_AC_THREAD_HEADER): Add new case for `mcf` thread
	model

gcc/ChangeLog:
	* config/i386/mingw-mcfgthread.h: New file
	* config/i386/mingw32.h: Add builtin macro and default libraries
	for mcfgthread when thread model is `mcf`
	* config.gcc: Include 'i386/mingw-mcfgthread.h' when thread model
	is `mcf`
	* configure.ac: Recognize `mcf` as a valid thread model
	* config.in: Regenerate
	* configure: Regenerate

libatomic/ChangeLog:
	* configure.tgt: Add new case for `mcf` thread model

libgcc/ChangeLog:
	* config.host: Add new cases for `mcf` thread model
	* config/i386/gthr-mcf.h: New file
	* config/i386/t-mingw-mcfgthread: New file
	* config/i386/t-slibgcc-cygming: Add mcfgthread for libgcc DLL
	* configure: Regenerate

libstdc++-v3/ChangeLog:
	* libsupc++/atexit_thread.cc (__cxa_thread_atexit): Use
	implementation from mcfgthread if available
	* libsupc++/guard.cc (__cxa_guard_acquire, __cxa_guard_release,
	__cxa_guard_abort): Use implementations from mcfgthread if
	available
	* configure: Regenerate

config/gthr.m4

@@ -22,6 +22,7 @@ case $1 in
     tpf)	thread_header=config/s390/gthr-tpf.h ;;
     vxworks)	thread_header=config/gthr-vxworks.h ;;
     win32)	thread_header=config/i386/gthr-win32.h ;;
+    mcf)	thread_header=config/i386/gthr-mcf.h ;;
 esac
 AC_SUBST(thread_header)
 ])

gcc/config.gcc

@@ -2096,6 +2096,9 @@ i[34567]86-*-mingw* | x86_64-*-mingw*)
 	if test x$enable_threads = xposix ; then
 		tm_file="${tm_file} i386/mingw-pthread.h"
 	fi
+	if test x$enable_threads = xmcf ; then
+		tm_file="${tm_file} i386/mingw-mcfgthread.h"
+	fi
 	tm_file="${tm_file} i386/mingw32.h"
 	# This makes the logic if mingw's or the w64 feature set has to be used
 	case ${target} in

gcc/config.in

@@ -1451,6 +1451,12 @@
 #endif
 
 
+/* Define to 1 if you have the `getauxval' function. */
+#ifndef USED_FOR_TARGET
+#undef HAVE_GETAUXVAL
+#endif
+
+
 /* Define to 1 if you have the `getchar_unlocked' function. */
 #ifndef USED_FOR_TARGET
 #undef HAVE_GETCHAR_UNLOCKED
@@ -2678,7 +2684,3 @@
 #undef vfork
 #endif
 
-/* Define to 1 if you have the `getauxval' function. */
-#ifndef USED_FOR_TARGET
-#undef HAVE_GETAUXVAL
-#endif

gcc/config/i386/mingw-mcfgthread.h

@@ -0,0 +1 @@
+#define TARGET_USING_MCFGTHREAD  1

gcc/config/i386/mingw32.h

@@ -32,6 +32,10 @@ along with GCC; see the file COPYING3.  If not see
 	 | MASK_STACK_PROBE | MASK_ALIGN_DOUBLE \
 	 | MASK_MS_BITFIELD_LAYOUT)
 
+#ifndef TARGET_USING_MCFGTHREAD
+#define TARGET_USING_MCFGTHREAD  0
+#endif
+
 /* See i386/crtdll.h for an alternative definition. _INTEGRAL_MAX_BITS
    is for compatibility with native compiler.  */
 #define EXTRA_OS_CPP_BUILTINS()					\
@@ -50,6 +54,8 @@ along with GCC; see the file COPYING3.  If not see
 	  builtin_define_std ("WIN64");				\
 	  builtin_define ("_WIN64");				\
 	}							\
+      if (TARGET_USING_MCFGTHREAD)				\
+	builtin_define ("__USING_MCFGTHREAD__");		\
     }								\
   while (0)
 
@@ -181,11 +187,16 @@ along with GCC; see the file COPYING3.  If not see
 #else
 #define SHARED_LIBGCC_SPEC " -lgcc "
 #endif
+#if TARGET_USING_MCFGTHREAD
+#define MCFGTHREAD_SPEC  " -lmcfgthread -lkernel32 -lntdll "
+#else
+#define MCFGTHREAD_SPEC  ""
+#endif
 #undef REAL_LIBGCC_SPEC
 #define REAL_LIBGCC_SPEC \
   "%{mthreads:-lmingwthrd} -lmingw32 \
    " SHARED_LIBGCC_SPEC " \
-   -lmoldname -lmingwex -lmsvcrt -lkernel32"
+   -lmoldname -lmingwex -lmsvcrt -lkernel32 " MCFGTHREAD_SPEC
 
 #undef STARTFILE_SPEC
 #define STARTFILE_SPEC "%{shared|mdll:dllcrt2%O%s} \

gcc/configure

@@ -12900,7 +12900,7 @@ case ${enable_threads} in
     target_thread_file='single'
     ;;
   aix | dce | lynx | mipssde | posix | rtems | \
-  single | tpf | vxworks | win32)
+  single | tpf | vxworks | win32 | mcf)
     target_thread_file=${enable_threads}
     ;;
   *)

gcc/configure.ac

@@ -1991,7 +1991,7 @@ case ${enable_threads} in
     target_thread_file='single'
     ;;
   aix | dce | lynx | mipssde | posix | rtems | \
-  single | tpf | vxworks | win32)
+  single | tpf | vxworks | win32 | mcf)
     target_thread_file=${enable_threads}
     ;;
   *)

libatomic/configure.tgt

@@ -159,7 +159,7 @@ case "${target}" in
   *-*-mingw*)
 	# OS support for atomic primitives.
         case ${target_thread_file} in
-          win32)
+          win32 | mcf)
             config_path="${config_path} mingw"
             ;;
           posix)

libgcc/config.host

@@ -825,6 +825,9 @@ i[34567]86-*-mingw*)
 	  posix)
 	    tmake_file="i386/t-mingw-pthread $tmake_file"
 	    ;;
+	  mcf)
+	    tmake_file="i386/t-mingw-mcfgthread $tmake_file"
+	    ;;
 	esac
 	# This has to match the logic for DWARF2_UNWIND_INFO in gcc/config/i386/cygming.h
 	if test x$ac_cv_sjlj_exceptions = xyes; then
@@ -849,6 +852,9 @@ x86_64-*-mingw*)
 	  posix)
 	    tmake_file="i386/t-mingw-pthread $tmake_file"
 	    ;;
+	  mcf)
+	    tmake_file="i386/t-mingw-mcfgthread $tmake_file"
+	    ;;
 	esac
 	# This has to match the logic for DWARF2_UNWIND_INFO in gcc/config/i386/cygming.h
 	if test x$ac_cv_sjlj_exceptions = xyes; then

libgcc/config/i386/gthr-mcf.h

@@ -0,0 +1 @@
+#include <mcfgthread/gthr.h>

libgcc/config/i386/t-mingw-mcfgthread

@@ -0,0 +1 @@
+SHLIB_MCFGTHREAD_LIBS = -lmcfgthread -lkernel32 -lntdll

libgcc/config/i386/t-slibgcc-cygming

@@ -27,6 +27,9 @@ endif
 ifndef SHLIB_PTHREAD_LDFLAG
 SHLIB_PTHREAD_LDFLAG =
 endif
+ifndef SHLIB_MCFGTHREAD_LIBS
+SHLIB_MCFGTHREAD_LIBS =
+endif
 
 SHLIB_LINK = $(LN_S) -f $(SHLIB_MAP) $(SHLIB_MAP).def && \
 	if [ ! -d $(SHLIB_DIR) ]; then \
@@ -37,7 +40,8 @@ SHLIB_LINK = $(LN_S) -f $(SHLIB_MAP) $(SHLIB_MAP).def && \
 	$(SHLIB_MAP).def \
 	-Wl,--out-implib,$(SHLIB_DIR)/$(SHLIB_IMPLIB).tmp \
 	-o $(SHLIB_DIR)/$(SHLIB_SONAME).tmp @multilib_flags@ \
-	$(SHLIB_OBJS) ${SHLIB_PTHREAD_LDFLAG} $(SHLIB_LC) && \
+	$(SHLIB_OBJS) ${SHLIB_PTHREAD_LDFLAG} $(SHLIB_LC) \
+	$(SHLIB_MCFGTHREAD_LIBS) && \
 	if [ -f $(SHLIB_DIR)/$(SHLIB_SONAME) ]; then \
 	  mv -f $(SHLIB_DIR)/$(SHLIB_SONAME) \
 		$(SHLIB_DIR)/$(SHLIB_SONAME).backup; \

libgcc/configure

@@ -5699,6 +5699,7 @@ case $target_thread_file in
     tpf)	thread_header=config/s390/gthr-tpf.h ;;
     vxworks)	thread_header=config/gthr-vxworks.h ;;
     win32)	thread_header=config/i386/gthr-win32.h ;;
+    mcf)	thread_header=config/i386/gthr-mcf.h ;;
 esac
 
 

libstdc++-v3/configure

@@ -15855,6 +15855,7 @@ case $target_thread_file in
     tpf)	thread_header=config/s390/gthr-tpf.h ;;
     vxworks)	thread_header=config/gthr-vxworks.h ;;
     win32)	thread_header=config/i386/gthr-win32.h ;;
+    mcf)	thread_header=config/i386/gthr-mcf.h ;;
 esac
 
 
@@ -16062,7 +16063,7 @@ $as_echo "$glibcxx_cv_atomic_long_long" >&6; }
   # Fake what AC_TRY_COMPILE does.
 
     cat > conftest.$ac_ext << EOF
-#line 16065 "configure"
+#line 16066 "configure"
 int main()
 {
   typedef bool atomic_type;
@@ -16097,7 +16098,7 @@ $as_echo "$glibcxx_cv_atomic_bool" >&6; }
     rm -f conftest*
 
     cat > conftest.$ac_ext << EOF
-#line 16100 "configure"
+#line 16101 "configure"
 int main()
 {
   typedef short atomic_type;
@@ -16132,7 +16133,7 @@ $as_echo "$glibcxx_cv_atomic_short" >&6; }
     rm -f conftest*
 
     cat > conftest.$ac_ext << EOF
-#line 16135 "configure"
+#line 16136 "configure"
 int main()
 {
   // NB: _Atomic_word not necessarily int.
@@ -16168,7 +16169,7 @@ $as_echo "$glibcxx_cv_atomic_int" >&6; }
     rm -f conftest*
 
     cat > conftest.$ac_ext << EOF
-#line 16171 "configure"
+#line 16172 "configure"
 int main()
 {
   typedef long long atomic_type;
@@ -16324,7 +16325,7 @@ $as_echo "mutex" >&6; }
   # unnecessary for this test.
 
     cat > conftest.$ac_ext << EOF
-#line 16327 "configure"
+#line 16328 "configure"
 int main()
 {
   _Decimal32 d1;
@@ -16366,7 +16367,7 @@ ac_compiler_gnu=$ac_cv_cxx_compiler_gnu
   # unnecessary for this test.
 
   cat > conftest.$ac_ext << EOF
-#line 16369 "configure"
+#line 16370 "configure"
 template<typename T1, typename T2>
   struct same
   { typedef T2 type; };

libstdc++-v3/libsupc++/atexit_thread.cc

@@ -25,6 +25,24 @@
 #include <cstdlib>
 #include <new>
 #include "bits/gthr.h"
+
+#ifdef __USING_MCFGTHREAD__
+
+#include <mcfgthread/cxa.h>
+
+namespace __cxxabiv1 {
+
+extern "C" int
+__cxa_thread_atexit (void (_GLIBCXX_CDTOR_CALLABI *dtor)(void *),
+		     void *obj, void *dso_handle) _GLIBCXX_NOTHROW
+{
+  return __MCF_cxa_thread_atexit (dtor, obj, dso_handle);
+}
+
+}  // namespace __cxxabiv1
+
+#else // __USING_MCFGTHREAD__
+
 #ifdef _GLIBCXX_THREAD_ATEXIT_WIN32
 #define WIN32_LEAN_AND_MEAN
 #include <windows.h>
@@ -173,3 +191,5 @@ __cxxabiv1::__cxa_thread_atexit (void (_GLIBCXX_CDTOR_CALLABI *dtor)(void *),
 }
 
 #endif /* _GLIBCXX_HAVE___CXA_THREAD_ATEXIT_IMPL */
+
+#endif // __USING_MCFGTHREAD__

libstdc++-v3/libsupc++/guard.cc

@@ -28,6 +28,35 @@
 #include <cxxabi.h>
 #include <exception>
 #include <new>
+
+#ifdef __USING_MCFGTHREAD__
+
+#include <mcfgthread/cxa.h>
+
+namespace __cxxabiv1 {
+
+extern "C" int
+__cxa_guard_acquire (__guard* g) _GLIBCXX_NOTHROW
+  {
+    return __MCF_cxa_guard_acquire(g);
+  }
+
+extern "C" void
+__cxa_guard_release (__guard* g) _GLIBCXX_NOTHROW
+  {
+    __MCF_cxa_guard_release(g);
+  }
+
+extern "C" void
+__cxa_guard_abort (__guard* g) _GLIBCXX_NOTHROW
+  {
+    __MCF_cxa_guard_abort(g);
+  }
+
+}  // namespace __cxxabiv1
+
+#else // __USING_MCFGTHREAD__
+
 #include <ext/atomicity.h>
 #include <ext/concurrence.h>
 #include <bits/atomic_lockfree_defines.h>
@@ -458,3 +487,5 @@ namespace __cxxabiv1
 #endif
   }
 }
+
+#endif // __USING_MCFGTHREAD__