PING: PATCH: PR target/46770: Use .init_array/.fini_array sections

diff --git a/gcc/config.gcc b/gcc/config.gcc
index 2cf92d2..e8aed1c 100644
--- a/gcc/config.gcc
+++ b/gcc/config.gcc
@@ -186,6 +186,9 @@ 
 #  configure_default_options
 #			Set to an initializer for configure_default_options
 #			in configargs.h, based on --with-cpu et cetera.
+#
+#  use_initfini_array	If set to yes, .init_array/.fini_array sections
+#			will be used if they work.
 
 # The following variables are used in each case-construct to build up the
 # outgoing variables:
@@ -238,6 +241,7 @@  default_gnu_indirect_function=no
 target_gtfiles=
 need_64bit_hwint=
 need_64bit_isa=
+use_initfini_array=yes
 
 # Don't carry these over build->host->target.  Please.
 xm_file=
@@ -3046,6 +3050,16 @@  if test x$with_schedule = x; then
 	esac
 fi
 
+# Support --enable-initfini-array.  Use initfini-array.h only if
+# use_initfini_array is also set to yes.  Some platforms don't need it
+# even if enable_initfini_array is yes.
+if test x$enable_initfini_array$use_initfini_array = xyesyes; then
+  tm_file="${tm_file} initfini-array.h"
+  tmake_file="${tmake_file} t-initfini-array"
+  extra_objs="$extra_objs initfini-array.o"
+  target_gtfiles="$target_gtfiles \$(srcdir)/config/initfini-array.c"
+fi
+
 # Validate and mark as valid any --with options supported
 # by this target.  In order to use a particular --with option
 # you must list it in supported_defaults; validating the value
diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
index 547acc8..7b7308f 100644
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -22833,6 +22833,9 @@  arm_asm_init_sections (void)
 {
   exception_section = get_unnamed_section (0, output_section_asm_op,
 					   "\t.handlerdata");
+#ifdef NO_CTORS_DTORS_SECTIONS
+  elf_initfini_array_init_sections ();
+#endif
 }
 #endif /* ARM_UNWIND_INFO */
 
diff --git a/gcc/config/avr/avr.c b/gcc/config/avr/avr.c
index e46ccd3..fd78e49 100644
--- a/gcc/config/avr/avr.c
+++ b/gcc/config/avr/avr.c
@@ -5271,6 +5271,10 @@  avr_asm_init_sections (void)
 					 NULL);
   readonly_data_section = data_section;
 
+#ifdef NO_CTORS_DTORS_SECTIONS
+  elf_initfini_array_init_sections ();
+#endif
+
   data_section->unnamed.callback = avr_output_data_section_asm_op;
   bss_section->unnamed.callback = avr_output_bss_section_asm_op;
 }
diff --git a/gcc/config/ia64/ia64.c b/gcc/config/ia64/ia64.c
index 78d2441..e66f8b1 100644
--- a/gcc/config/ia64/ia64.c
+++ b/gcc/config/ia64/ia64.c
@@ -10045,6 +10045,9 @@  ia64_asm_init_sections (void)
 {
   exception_section = get_unnamed_section (0, output_section_asm_op,
 					   "\t.handlerdata");
+#ifdef NO_CTORS_DTORS_SECTIONS
+  elf_initfini_array_init_sections ();
+#endif
 }
 
 /* Implement TARGET_DEBUG_UNWIND_INFO.  */
diff --git a/gcc/config/initfini-array.c b/gcc/config/initfini-array.c
new file mode 100644
index 0000000..c042769
--- /dev/null
+++ b/gcc/config/initfini-array.c
@@ -0,0 +1,80 @@ 
+/* Definitions for ELF systems with .init_array/.fini_array section
+   Copyright (C) 2011
+   Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "target.h"
+#include "output.h"
+#include "tree.h"
+#include "initfini-array.h"
+#include "ggc.h"
+
+static GTY(()) section *init_array_section;
+static GTY(()) section *fini_array_section;
+
+void
+elf_initfini_array_init_sections (void)
+{
+  init_array_section = get_unnamed_section (0, output_section_asm_op,
+					    "\t.section\t.init_array");
+  fini_array_section = get_unnamed_section (0, output_section_asm_op,
+					    "\t.section\t.fini_array");
+}
+
+static section *
+get_elf_initfini_array_priority_section (int priority,
+					 bool constructor_p)
+{
+  section *sec;
+  if (priority != DEFAULT_INIT_PRIORITY)
+    {
+      char buf[18];
+      sprintf (buf, "%s.%.5u", 
+	       constructor_p ? ".init_array" : ".fini_array",
+	       priority);
+      sec = get_section (buf, SECTION_WRITE, NULL_TREE);
+    }
+  else
+    sec = constructor_p ? init_array_section : fini_array_section;
+  return sec;
+}
+
+/* Use .init_array section for constructors. */
+
+void
+elf_init_array_asm_out_constructor (rtx symbol, int priority)
+{
+  section *sec = get_elf_initfini_array_priority_section (priority,
+							  true);
+  assemble_addr_to_section (symbol, sec);
+}
+
+/* Use .fini_array section for destructors. */
+
+void
+elf_fini_array_asm_out_destructor (rtx symbol, int priority)
+{
+  section *sec = get_elf_initfini_array_priority_section (priority,
+							  false);
+  assemble_addr_to_section (symbol, sec);
+}
+
+#include "gt-initfini-array.h"
diff --git a/gcc/config/initfini-array.h b/gcc/config/initfini-array.h
new file mode 100644
index 0000000..cba7eca
--- /dev/null
+++ b/gcc/config/initfini-array.h
@@ -0,0 +1,46 @@ 
+/* Definitions for ELF systems with .init_array/.fini_array section
+   support.
+   Copyright (C) 2011
+   Free Software Foundation, Inc.
+
+   This file is part of GCC.
+
+   GCC is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published
+   by the Free Software Foundation; either version 3, or (at your
+   option) any later version.
+
+   GCC is distributed in the hope that it will be useful, but WITHOUT
+   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+   or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
+   License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with GCC; see the file COPYING3.  If not see
+   <http://www.gnu.org/licenses/>.  */
+
+/* No need for .ctors/.dtors section since linker can place them in
+   .init_array/.fini_array section.  */
+#define NO_CTORS_DTORS_SECTIONS
+
+#undef INIT_SECTION_ASM_OP
+#undef FINI_SECTION_ASM_OP
+
+/* FIXME: INIT_ARRAY_SECTION_ASM_OP and FINI_ARRAY_SECTION_ASM_OP
+	  aren't used in any assembly codes.  But we have to define
+	  them to something.  */
+#define INIT_ARRAY_SECTION_ASM_OP Something
+#define FINI_ARRAY_SECTION_ASM_OP Something
+
+#ifndef TARGET_ASM_INIT_SECTIONS
+#define TARGET_ASM_INIT_SECTIONS elf_initfini_array_init_sections
+#endif
+extern void elf_initfini_array_init_sections (void);
+
+/* Use .init_array/.fini_array section for constructors and destructors. */
+#undef TARGET_ASM_CONSTRUCTOR
+#define TARGET_ASM_CONSTRUCTOR elf_init_array_asm_out_constructor
+#undef TARGET_ASM_DESTRUCTOR
+#define TARGET_ASM_DESTRUCTOR elf_fini_array_asm_out_destructor
+extern void elf_init_array_asm_out_constructor (rtx, int);
+extern void elf_fini_array_asm_out_destructor (rtx, int);
diff --git a/gcc/config/mep/mep.c b/gcc/config/mep/mep.c
index a946c93..cdfd29a 100644
--- a/gcc/config/mep/mep.c
+++ b/gcc/config/mep/mep.c
@@ -7341,6 +7341,9 @@  mep_asm_init_sections (void)
     = get_unnamed_section (SECTION_CODE, output_section_asm_op,
 			   "\t.section .ftext,\"ax\"\n\t.core");
 
+#ifdef NO_CTORS_DTORS_SECTIONS
+  elf_initfini_array_init_sections ();
+#endif
 }
 
 /* Initialize the GCC target structure.  */
diff --git a/gcc/config/microblaze/microblaze.c b/gcc/config/microblaze/microblaze.c
index 288b86f..6b77e4a 100644
--- a/gcc/config/microblaze/microblaze.c
+++ b/gcc/config/microblaze/microblaze.c
@@ -2753,6 +2753,9 @@  microblaze_elf_asm_init_sections (void)
   sdata2_section
     = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
 			   SDATA2_SECTION_ASM_OP);
+#ifdef NO_CTORS_DTORS_SECTIONS
+  elf_initfini_array_init_sections ();
+#endif
 }
 
 /*  Generate assembler code for constant parts of a trampoline.  */
diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index c15c04e..83968f9 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -24828,6 +24828,10 @@  rs6000_elf_asm_init_sections (void)
   sdata2_section
     = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
 			   SDATA2_SECTION_ASM_OP);
+
+#ifdef NO_CTORS_DTORS_SECTIONS
+  elf_initfini_array_init_sections ();
+#endif
 }
 
 /* Implement TARGET_SELECT_RTX_SECTION.  */
diff --git a/gcc/config/stormy16/stormy16.c b/gcc/config/stormy16/stormy16.c
index 9796528..b194b44 100644
--- a/gcc/config/stormy16/stormy16.c
+++ b/gcc/config/stormy16/stormy16.c
@@ -1573,6 +1573,9 @@  xstormy16_asm_init_sections (void)
     = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
 			   output_section_asm_op,
 			   "\t.section \".bss_below100\",\"aw\",@nobits");
+#ifdef NO_CTORS_DTORS_SECTIONS
+  elf_initfini_array_init_sections ();
+#endif
 }
 
 /* Mark symbols with the "below100" attribute so that we can use the
diff --git a/gcc/config/t-initfini-array b/gcc/config/t-initfini-array
new file mode 100644
index 0000000..3824ed4
--- /dev/null
+++ b/gcc/config/t-initfini-array
@@ -0,0 +1,23 @@ 
+# Copyright (C) 2011
+# 2009 Free Software Foundation, Inc.
+#
+# This file is part of GCC.
+#
+# GCC is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3, or (at your option)
+# any later version.
+#
+# GCC is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with GCC; see the file COPYING3.  If not see
+# <http://www.gnu.org/licenses/>.
+
+initfini-array.o: $(srcdir)/config/initfini-array.c gt-initfini-array.h \
+	$(CONFIG_H) $(SYSTEM_H) coretypes.h $(TARGET_H) output.h \
+	$(TREE_H) $(GGC_H)
+	$(COMPILER) -c $(ALL_COMPILERFLAGS) $(ALL_CPPFLAGS) $(INCLUDES) $<
diff --git a/gcc/config/v850/v850.c b/gcc/config/v850/v850.c
index 5074ebe..4e7872a 100644
--- a/gcc/config/v850/v850.c
+++ b/gcc/config/v850/v850.c
@@ -2900,6 +2900,10 @@  v850_asm_init_sections (void)
     = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
 			   output_section_asm_op,
 			   "\t.section .zbss,\"aw\"");
+
+#ifdef NO_CTORS_DTORS_SECTIONS
+  elf_initfini_array_init_sections ();
+#endif
 }
 
 static section *
diff --git a/gcc/crtstuff.c b/gcc/crtstuff.c
index b65f490..bccf44d 100644
--- a/gcc/crtstuff.c
+++ b/gcc/crtstuff.c
@@ -1,7 +1,8 @@ 
 /* Specialized bits of code needed to support construction and
    destruction of file-scope objects in C++ code.
    Copyright (C) 1991, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001
-   2002, 2003, 2004, 2005, 2006, 2007, 2009, 2010 Free Software Foundation, Inc.
+   2002, 2003, 2004, 2005, 2006, 2007, 2009, 2010, 2011
+   Free Software Foundation, Inc.
    Contributed by Ron Guilmette (rfg@monkeys.com).
 
 This file is part of GCC.
@@ -189,6 +190,9 @@  typedef void (*func_ptr) (void);
    refer to only the __CTOR_END__ symbol in crtend.o and the __DTOR_LIST__
    symbol in crtbegin.o, where they are defined.  */
 
+/* No need for .ctors/.dtors section if linker can place them in
+   .init_array/.fini_array section.  */
+#ifndef NO_CTORS_DTORS_SECTIONS
 /* The -1 is a flag to __do_global_[cd]tors indicating that this table
    does not start with a count of elements.  */
 #ifdef CTOR_LIST_BEGIN
@@ -219,6 +223,7 @@  STATIC func_ptr __DTOR_LIST__[1]
   __attribute__((section(".dtors"), aligned(sizeof(func_ptr))))
   = { (func_ptr) (-1) };
 #endif /* __DTOR_LIST__ alternatives */
+#endif /* NO_CTORS_DTORS_SECTIONS */
 
 #ifdef USE_EH_FRAME_REGISTRY
 /* Stick a label at the beginning of the frame unwind info so we can register
@@ -489,6 +494,9 @@  __do_global_ctors_1(void)
 
 #elif defined(CRT_END) /* ! CRT_BEGIN */
 
+/* No need for .ctors/.dtors section if linker can place them in
+   .init_array/.fini_array section.  */
+#ifndef NO_CTORS_DTORS_SECTIONS
 /* Put a word containing zero at the end of each of our two lists of function
    addresses.  Note that the words defined here go into the .ctors and .dtors
    sections of the crtend.o file, and since that file is always linked in
@@ -534,6 +542,7 @@  STATIC func_ptr __DTOR_END__[1]
   __attribute__((used, section(".dtors"), aligned(sizeof(func_ptr))))
   = { (func_ptr) 0 };
 #endif
+#endif /* NO_CTORS_DTORS_SECTIONS */
 
 #ifdef EH_FRAME_SECTION_NAME
 /* Terminate the frame unwind info section with a 4byte 0 as a sentinel;