PATCH: libgcc: Enable TLS for Linux/x86

[H.J. Lu]

On Thu, Jul 05, 2007 at 05:44:27PM +0200, Paolo Bonzini wrote:
> 
> >Paolo, what about old binutils?  I don't know what we require nowadays
> >but I doubt it's sufficient for __thread.  I think we still need a
> >link test, or at least an assembler test.
> 
> Agreed.  I thought I had specified that, but I only mentioned testing 
> the triplet.
> 

Here is the updated patch. I added AS_CHECK_TLS to config/tls.m4.
Tested on Linux/Intel64.


H.J.
---
config/

2007-07-05  H.J. Lu  <hongjiu.lu@intel.com>

	* tls.m4 (AS_CHECK_TLS): New.

libgcc/

2007-07-05  H.J. Lu  <hongjiu.lu@intel.com>

	* config.host (tmake_file): Add t-tls for i[34567]86-*-linux*
	and x86_64-*-linux*.

	* config/t-tls: New file.

	* Makefile.in (gcc_compile_bare): Add @set_have_as_tls@. 

	* configure.ac: Include ../config/enable.m4 and
	../config/tls.m4.  Use AS_CHECK_TLS to check if assembler
	supports TLS and substitute set_have_as_tls.

libbid/

2007-07-05  H.J. Lu  <hongjiu.lu@intel.com>

	* bid_conf.h (BID_THREAD): Defined only if both HAVE_AS_TLS
	and USE_TLS are defined.

--- gcc/config/tls.m4.tls	2007-02-11 07:29:47.000000000 -0800
+++ gcc/config/tls.m4	2007-07-05 13:50:46.000000000 -0700
@@ -73,3 +73,16 @@ AC_DEFUN([GCC_CHECK_TLS], [
     AC_DEFINE(HAVE_TLS, 1,
 	      [Define to 1 if the target supports thread-local storage.])
   fi])
+
+dnl Check whether the target assembler supports TLS.
+AC_DEFUN([AS_CHECK_TLS], [
+  GCC_ENABLE(tls, yes, [], [Use thread-local storage])
+  AC_CACHE_CHECK([whether the target asssembler upports thread-local storage],
+		 have_as_tls, [
+    AC_COMPILE_IFELSE([__thread int a; int b; int main() { return a = b; }],
+      [have_as_tls=yes], [have_as_tls=no])]
+    )])
+  if test "$enable_tls $have_as_tls" = "yes yes"; then
+    AC_DEFINE(HAVE_AS_TLS, 1,
+	      [Define to 1 if the target assembler supports thread-local storage.])
+  fi])
--- gcc/libgcc/Makefile.in.tls	2007-07-05 07:16:20.000000000 -0700
+++ gcc/libgcc/Makefile.in	2007-07-05 14:05:46.000000000 -0700
@@ -225,7 +225,8 @@ MULTIOSSUBDIR := $(shell if test $(MULTI
 inst_libdir = $(libsubdir)$(MULTISUBDIR)
 inst_slibdir = $(slibdir)$(MULTIOSSUBDIR)
 
-gcc_compile_bare = $(CC) $(INTERNAL_CFLAGS)
+# If we can use thread-local storage
+gcc_compile_bare = $(CC) $(INTERNAL_CFLAGS) @set_have_as_tls@
 compile_deps = -MT $@ -MD -MP -MF $(basename $@).dep
 gcc_compile = $(gcc_compile_bare) -o $@ $(compile_deps)
 gcc_s_compile = $(gcc_compile) -DSHARED
--- gcc/libgcc/config.host.tls	2007-06-14 05:12:39.000000000 -0700
+++ gcc/libgcc/config.host	2007-07-05 07:16:21.000000000 -0700
@@ -654,3 +654,9 @@ m32c-*-elf*)
 	exit 1
 	;;
 esac
+
+case ${host} in
+i[34567]86-*-linux* | x86_64-*-linux*)
+	tmake_file="${tmake_file} t-tls"
+	;;
+esac
--- gcc/libgcc/config/libbid/bid_conf.h.tls	2007-07-05 07:13:24.000000000 -0700
+++ gcc/libgcc/config/libbid/bid_conf.h	2007-07-05 13:38:41.000000000 -0700
@@ -41,7 +41,7 @@ Software Foundation, 51 Franklin Street,
 #endif
 
 #ifndef BID_THREAD
-#ifdef USE_TLS
+#if defined (HAVE_AS_TLS) && defined (USE_TLS)
 #define BID_THREAD __thread
 #endif
 #endif
--- gcc/libgcc/config/t-tls.tls	2007-07-05 07:16:21.000000000 -0700
+++ gcc/libgcc/config/t-tls	2007-07-05 07:16:21.000000000 -0700
@@ -0,0 +1,2 @@
+# Use thread-local storage
+gcc_compile_bare += -DUSE_TLS
--- gcc/libgcc/configure.ac.tls	2007-07-05 07:16:20.000000000 -0700
+++ gcc/libgcc/configure.ac	2007-07-05 13:59:54.000000000 -0700
@@ -1,5 +1,7 @@
 dnl Process this file with autoconf to produce a configure script.
 
+sinclude(../config/enable.m4)
+sinclude(../config/tls.m4)
 sinclude(../config/acx.m4)
 sinclude(../config/no-executables.m4)
 sinclude(../config/lib-ld.m4)
@@ -169,6 +171,17 @@ else
 fi
 AC_SUBST(vis_hide)
 
+# See if we have thread-local storage.  We can only test assembler
+# sicne link-time and run-time tests require the newly built
+# gcc, which can't be used to build executable due to that libgcc
+# is yet to be built here.
+AS_CHECK_TLS
+set_have_as_tls
+if test "$enable_tls $have_as_tls" = "yes yes"; then
+  set_have_as_tls="-DHAVE_AS_TLS"
+fi
+AC_SUBST(set_have_as_tls)
+
 # Conditionalize the makefile for this target machine.
 tmake_file_=
 for f in ${tmake_file}