Implement TARGET_ATOMIC_ASSIGN_EXPAND_FENV for powerpc*-*-linux* soft-float and e500.

This patch implements support for TARGET_ATOMIC_ASSIGN_EXPAND_FENV for
powerpc*-*-linux* soft-float and e500, provided GCC is configured for
glibc 2.19 or later on the target.

New functions __atomic_feholdexcept, __atomic_feclearexcept and
__atomic_feupdateenv were added (to libc) in that glibc version (for
powerpc soft-float / e500 only) in order to support this part of C11.
For soft-float, libc functions are needed because the floating-point
exception state is in TLS variables in libc that aren't directly
accessible outside of glibc.  For e500, they are also needed because
of the prctl syscalls involved in controlling trapping for exceptions
and informing the kernel when certain exception flags have been
cleared.  The actual implementation in GCC is a straightforward matter
of calling those functions.

Tested with no regressions for cross to powerpc-linux-gnu
(soft-float); the c11-atomic-exec-5.c results go from FAIL to PASS.

	* configure.ac (TARGET_GLIBC_MAJOR, TARGET_GLIBC_MINOR): Define
	macros.
	* configure, config.h.in: Regenerate.
	* config/rs6000/linux.h [TARGET_GLIBC_MAJOR > 2 ||
	(TARGET_GLIBC_MAJOR == 2 && TARGET_GLIBC_MINOR >= 19)]
	(RS6000_GLIBC_ATOMIC_FENV): New macro.
	* config/rs6000/linux64.h [TARGET_GLIBC_MAJOR > 2 ||
	(TARGET_GLIBC_MAJOR == 2 && TARGET_GLIBC_MINOR >= 19)]
	(RS6000_GLIBC_ATOMIC_FENV): New macro.
	* config/rs6000/rs6000.c (atomic_hold_decl, atomic_clear_decl)
	(atomic_update_decl): New static variables.
	(rs6000_atomic_assign_expand_fenv) [RS6000_GLIBC_ATOMIC_FENV]:
	Generate calls to __atomic_feholdexcept, __atomic_feclearexcept
	and __atomic_feupdateenv for soft-float and no-FPRs.

From-SVN: r217040

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 9025278f1cfff45c430a81029bf6044b41295b2e..e709e113c1cb83f4a5308690274059ed37ebadef 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,20 @@
+2014-11-03  Joseph Myers  <joseph@codesourcery.com>
+
+       * configure.ac (TARGET_GLIBC_MAJOR, TARGET_GLIBC_MINOR): Define
+       macros.
+       * configure, config.h.in: Regenerate.
+       * config/rs6000/linux.h [TARGET_GLIBC_MAJOR > 2 ||
+       (TARGET_GLIBC_MAJOR == 2 && TARGET_GLIBC_MINOR >= 19)]
+       (RS6000_GLIBC_ATOMIC_FENV): New macro.
+       * config/rs6000/linux64.h [TARGET_GLIBC_MAJOR > 2 ||
+       (TARGET_GLIBC_MAJOR == 2 && TARGET_GLIBC_MINOR >= 19)]
+       (RS6000_GLIBC_ATOMIC_FENV): New macro.
+       * config/rs6000/rs6000.c (atomic_hold_decl, atomic_clear_decl)
+       (atomic_update_decl): New static variables.
+       (rs6000_atomic_assign_expand_fenv) [RS6000_GLIBC_ATOMIC_FENV]:
+       Generate calls to __atomic_feholdexcept, __atomic_feclearexcept
+       and __atomic_feupdateenv for soft-float and no-FPRs.
+
 2014-11-03  Richard Biener  <rguenther@suse.de>
 
        * match.pd: Add two abs patterns.  Announce tree_expr_nonnegative_p.

diff --git a/gcc/config.in b/gcc/config.in
index 90809e37466ce57f3660c7107da4fac50c23d5a2..c4f9164ef7fae1815449c8d8425efba0356b4677 100644 (file)
--- a/gcc/config.in
+++ b/gcc/config.in
@@ -1699,16 +1699,19 @@
 #undef HAVE_WORKING_VFORK
 #endif
 
-/* Define if isl is in use. */
-#ifndef USED_FOR_TARGET
-#undef HAVE_isl
-#endif
 
 /* Define if cloog is in use. */
 #ifndef USED_FOR_TARGET
 #undef HAVE_cloog
 #endif
 
+
+/* Define if isl is in use. */
+#ifndef USED_FOR_TARGET
+#undef HAVE_isl
+#endif
+
+
 /* Define if F_SETLKW supported by fcntl. */
 #ifndef USED_FOR_TARGET
 #undef HOST_HAS_F_SETLKW
@@ -1882,6 +1885,18 @@
 /* Define if your target C library provides the `dl_iterate_phdr' function. */
 #undef TARGET_DL_ITERATE_PHDR
 
+/* GNU C Library major version number used on the target, or 0. */
+#ifndef USED_FOR_TARGET
+#undef TARGET_GLIBC_MAJOR
+#endif
+
+
+/* GNU C Library minor version number used on the target, or 0. */
+#ifndef USED_FOR_TARGET
+#undef TARGET_GLIBC_MINOR
+#endif
+
+
 /* Define if your target C library provides stack protector support */
 #ifndef USED_FOR_TARGET
 #undef TARGET_LIBC_PROVIDES_SSP

diff --git a/gcc/config/rs6000/linux.h b/gcc/config/rs6000/linux.h
index 7c83f1e78efc06e21e82e1ff519f08c7159b10b3..5067df6659d7981647501f513ae084336bfb5ae8 100644 (file)
--- a/gcc/config/rs6000/linux.h
+++ b/gcc/config/rs6000/linux.h
@@ -127,3 +127,10 @@
 #undef TARGET_FLOAT_EXCEPTIONS_ROUNDING_SUPPORTED_P
 #define TARGET_FLOAT_EXCEPTIONS_ROUNDING_SUPPORTED_P \
   rs6000_linux_float_exceptions_rounding_supported_p
+
+/* Support for TARGET_ATOMIC_ASSIGN_EXPAND_FENV without FPRs depends
+   on glibc 2.19 or greater.  */
+#if TARGET_GLIBC_MAJOR > 2 \
+  || (TARGET_GLIBC_MAJOR == 2 && TARGET_GLIBC_MINOR >= 19)
+#define RS6000_GLIBC_ATOMIC_FENV 1
+#endif

diff --git a/gcc/config/rs6000/linux64.h b/gcc/config/rs6000/linux64.h
index 39a2b172ac1114f0ed0375acc0907c2a33e5d1a6..5f74ed3429a19dd60eb60423b8e9f0be73c3de40 100644 (file)
--- a/gcc/config/rs6000/linux64.h
+++ b/gcc/config/rs6000/linux64.h
@@ -557,3 +557,10 @@ extern int dot_symbols;
 #undef TARGET_FLOAT_EXCEPTIONS_ROUNDING_SUPPORTED_P
 #define TARGET_FLOAT_EXCEPTIONS_ROUNDING_SUPPORTED_P \
   rs6000_linux_float_exceptions_rounding_supported_p
+
+/* Support for TARGET_ATOMIC_ASSIGN_EXPAND_FENV without FPRs depends
+   on glibc 2.19 or greater.  */
+#if TARGET_GLIBC_MAJOR > 2 \
+  || (TARGET_GLIBC_MAJOR == 2 && TARGET_GLIBC_MINOR >= 19)
+#define RS6000_GLIBC_ATOMIC_FENV 1
+#endif

diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index 05325c24d6d0d83daeebc984168ecb6e5661cbe0..719878c1f84e00bacb28ce45ff27e9604fa5bf2e 100644 (file)
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -34590,13 +34590,66 @@ make_pass_analyze_swaps (gcc::context *ctxt)
   return new pass_analyze_swaps (ctxt);
 }
 
+/* Function declarations for rs6000_atomic_assign_expand_fenv.  */
+static tree atomic_hold_decl, atomic_clear_decl, atomic_update_decl;
+
 /* Implement TARGET_ATOMIC_ASSIGN_EXPAND_FENV hook.  */
 
 static void
 rs6000_atomic_assign_expand_fenv (tree *hold, tree *clear, tree *update)
 {
   if (!TARGET_HARD_FLOAT || !TARGET_FPRS)
-    return;
+    {
+#ifdef RS6000_GLIBC_ATOMIC_FENV
+      if (atomic_hold_decl == NULL_TREE)
+       {
+         atomic_hold_decl
+           = build_decl (BUILTINS_LOCATION, FUNCTION_DECL,
+                         get_identifier ("__atomic_feholdexcept"),
+                         build_function_type_list (void_type_node,
+                                                   double_ptr_type_node,
+                                                   NULL_TREE));
+         TREE_PUBLIC (atomic_hold_decl) = 1;
+         DECL_EXTERNAL (atomic_hold_decl) = 1;
+       }
+
+      if (atomic_clear_decl == NULL_TREE)
+       {
+         atomic_clear_decl
+           = build_decl (BUILTINS_LOCATION, FUNCTION_DECL,
+                         get_identifier ("__atomic_feclearexcept"),
+                         build_function_type_list (void_type_node,
+                                                   NULL_TREE));
+         TREE_PUBLIC (atomic_clear_decl) = 1;
+         DECL_EXTERNAL (atomic_clear_decl) = 1;
+       }
+
+      tree const_double = build_qualified_type (double_type_node,
+                                               TYPE_QUAL_CONST);
+      tree const_double_ptr = build_pointer_type (const_double);
+      if (atomic_update_decl == NULL_TREE)
+       {
+         atomic_update_decl
+           = build_decl (BUILTINS_LOCATION, FUNCTION_DECL,
+                         get_identifier ("__atomic_feupdateenv"),
+                         build_function_type_list (void_type_node,
+                                                   const_double_ptr,
+                                                   NULL_TREE));
+         TREE_PUBLIC (atomic_update_decl) = 1;
+         DECL_EXTERNAL (atomic_update_decl) = 1;
+       }
+
+      tree fenv_var = create_tmp_var (double_type_node, NULL);
+      mark_addressable (fenv_var);
+      tree fenv_addr = build1 (ADDR_EXPR, double_ptr_type_node, fenv_var);
+
+      *hold = build_call_expr (atomic_hold_decl, 1, fenv_addr);
+      *clear = build_call_expr (atomic_clear_decl, 0);
+      *update = build_call_expr (atomic_update_decl, 1,
+                                fold_convert (const_double_ptr, fenv_addr));
+#endif
+      return;
+    }
 
   tree mffs = rs6000_builtin_decls[RS6000_BUILTIN_MFFS];
   tree mtfsf = rs6000_builtin_decls[RS6000_BUILTIN_MTFSF];

diff --git a/gcc/configure b/gcc/configure
index 4022332f5f0b56f9d16091ed5b201c40d4871e7d..40b2a87082b47f74bb855a4d9a0b74d5f6a00fd2 100755 (executable)
--- a/gcc/configure
+++ b/gcc/configure
@@ -26700,6 +26700,16 @@ fi
 { $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibc_version_major.$glibc_version_minor" >&5
 $as_echo "$glibc_version_major.$glibc_version_minor" >&6; }
 
+cat >>confdefs.h <<_ACEOF
+#define TARGET_GLIBC_MAJOR $glibc_version_major
+_ACEOF
+
+
+cat >>confdefs.h <<_ACEOF
+#define TARGET_GLIBC_MINOR $glibc_version_minor
+_ACEOF
+
+
 # Check whether --enable-gnu-unique-object was given.
 if test "${enable_gnu_unique_object+set}" = set; then :
   enableval=$enable_gnu_unique_object; case $enable_gnu_unique_object in

diff --git a/gcc/configure.ac b/gcc/configure.ac
index 02bb3066795f75d88e201f7b147c2142f907bcac..dc14b457a5b169f1d853c1828d87643ae9d80f38 100644 (file)
--- a/gcc/configure.ac
+++ b/gcc/configure.ac
@@ -4503,6 +4503,10 @@ glibc_version_minor=0
   glibc_version_minor=`echo "$glibc_version_minor_define" | sed -e 's/.*__GLIBC_MINOR__[       ]*//'`
 fi]])
 AC_MSG_RESULT([$glibc_version_major.$glibc_version_minor])
+AC_DEFINE_UNQUOTED([TARGET_GLIBC_MAJOR], [$glibc_version_major],
+[GNU C Library major version number used on the target, or 0.])
+AC_DEFINE_UNQUOTED([TARGET_GLIBC_MINOR], [$glibc_version_minor],
+[GNU C Library minor version number used on the target, or 0.])
 
 AC_ARG_ENABLE(gnu-unique-object,
  [AS_HELP_STRING([--enable-gnu-unique-object],