[NDS32] Support Linux target for nds32.

gcc/
	* config.gcc (nds32*): Use nds32-linux.opt and nds32-elf.opt.
	(nds32le-*-*, nds32be-*-*): Integrate checking process.
	(nds32*-*-*): Add glibc and uclibc conditions.
	* common/config/nds32/nds32-common.c (nds32_except_unwind_info): New.
	(TARGET_EXCEPT_UNWIND_INFO): Define.
	* config/nds32/elf.h: New file.
	* config/nds32/linux.h: New file.
	* config/nds32/nds32-elf.opt: New file.
	* config/nds32/nds32-linux.opt: New file.
	* config/nds32/nds32-fp-as-gp.c
	(pass_nds32_fp_as_gp::gate): Consider TARGET_LINUX_ABI.
	* config/nds32/nds32.c (nds32_conditional_register_usage): Consider
	TARGET_LINUX_ABI.
	(nds32_asm_file_end): Ditto.
	(nds32_print_operand): Ditto.
	(nds32_insert_attributes): Ditto.
	(nds32_init_libfuncs): New function.
	(TARGET_HAVE_TLS): Define.
	(TARGET_INIT_LIBFUNCS): Define.
	* config/nds32/nds32.h (TARGET_DEFAULT_RELAX): Apply different relax
	spec content.
	(TARGET_ELF): Apply different mcmodel setting.
	(LINK_SPEC, LIB_SPEC, STARTFILE_SPEC, ENDFILE_SPEC): The content has
	been migrated into elf.h and linux.h files.
	* config/nds32/nds32.md (add_pc): Consider TARGET_LINUX_ABI.
	* config/nds32/nds32.opt (mvh): Consider TARGET_LINUX_ABI.
	(mcmodel): The content has been migrated into nds32-elf.opt and
	nds32-linux.opt files.
	* config/nds32/t-elf: New file.
	* config/nds32/t-linux: New file.

libgcc/
	* config.host (nds32*-linux*): New.
	* config/nds32/linux-atomic.c: New file.
	* config/nds32/linux-unwind.h: New file.

Co-Authored-By: Kito Cheng <kito.cheng@gmail.com>
Co-Authored-By: Monk Chiang <sh.chiang04@gmail.com>

From-SVN: r261116

11 files changed, 317 insertions, 61 deletions

diff --git a/gcc/config/nds32/elf.h b/gcc/config/nds32/elf.h
new file mode 100644
index 0000000..66397ac
--- /dev/null
+++ b/gcc/config/nds32/elf.h
@@ -0,0 +1,81 @@
+/* Definitions of target machine of Andes NDS32 cpu for GNU compiler
+   Copyright (C) 2012-2014 Free Software Foundation, Inc.
+   Contributed by Andes Technology Corporation.
+
+   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/>.  */
+
+
+/* ------------------------------------------------------------------------ */
+
+#define TARGET_LINUX_ABI 0
+
+/* In the configure stage we may use options --enable-default-relax,
+   --enable-Os-default-ifc and --enable-Os-default-ex9.  They effect
+   the default spec of passing --relax, --mifc, and --mex9 to linker.
+   We use NDS32_RELAX_SPEC, NDS32_IFC_SPEC, and NDS32_EX9_SPEC
+   so that we can customize them conveniently.  */
+#define LINK_SPEC \
+  " %{G*}" \
+  " %{mbig-endian:-EB} %{mlittle-endian:-EL}" \
+  " %{shared:-shared}" \
+  NDS32_RELAX_SPEC
+
+#define LIB_SPEC \
+  " -lc -lgloss"
+
+#define LIBGCC_SPEC \
+  " -lgcc"
+
+/* The option -mno-ctor-dtor can disable constructor/destructor feature
+   by applying different crt stuff.  In the convention, crt0.o is the
+   startup file without constructor/destructor;
+   crt1.o, crti.o, crtbegin.o, crtend.o, and crtn.o are the
+   startup files with constructor/destructor.
+   Note that crt0.o, crt1.o, crti.o, and crtn.o are provided
+   by newlib/mculib/glibc/ublic, while crtbegin.o and crtend.o are
+   currently provided by GCC for nds32 target.
+
+   For nds32 target so far:
+   If -mno-ctor-dtor, we are going to link
+   "crt0.o [user objects]".
+   If -mctor-dtor, we are going to link
+   "crt1.o crtbegin1.o [user objects] crtend1.o".
+
+   Note that the TARGET_DEFAULT_CTOR_DTOR would effect the
+   default behavior.  Check gcc/config.gcc for more information.  */
+#ifdef TARGET_DEFAULT_CTOR_DTOR
+  #define STARTFILE_SPEC \
+    " %{!mno-ctor-dtor:crt1.o%s;:crt0.o%s}" \
+    " %{!mno-ctor-dtor:crtbegin1.o%s}" \
+    " %{mcrt-arg:crtarg.o%s}"
+  #define ENDFILE_SPEC \
+    " %{!mno-ctor-dtor:crtend1.o%s}"
+#else
+  #define STARTFILE_SPEC \
+    " %{mctor-dtor|coverage:crt1.o%s;:crt0.o%s}" \
+    " %{mctor-dtor|coverage:crtbegin1.o%s}" \
+    " %{mcrt-arg:crtarg.o%s}"
+  #define ENDFILE_SPEC \
+    " %{mctor-dtor|coverage:crtend1.o%s}"
+#endif
+
+#define STARTFILE_CXX_SPEC \
+  " %{!mno-ctor-dtor:crt1.o%s;:crt0.o%s}" \
+  " %{!mno-ctor-dtor:crtbegin1.o%s}" \
+  " %{mcrt-arg:crtarg.o%s}"
+#define ENDFILE_CXX_SPEC \
+  " %{!mno-ctor-dtor:crtend1.o%s}"
diff --git a/gcc/config/nds32/linux.h b/gcc/config/nds32/linux.h
new file mode 100644
index 0000000..a0ec1b2
--- /dev/null
+++ b/gcc/config/nds32/linux.h
@@ -0,0 +1,77 @@
+/* Definitions of target machine of Andes NDS32 cpu for GNU compiler
+   Copyright (C) 2012-2014 Free Software Foundation, Inc.
+   Contributed by Andes Technology Corporation.
+
+   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/>.  */
+
+
+/* ------------------------------------------------------------------------ */
+
+#define TARGET_LINUX_ABI 1
+
+#undef  SIZE_TYPE
+#define SIZE_TYPE "unsigned int"
+
+#undef  PTRDIFF_TYPE
+#define PTRDIFF_TYPE "int"
+
+#ifdef TARGET_DEFAULT_TLSDESC_TRAMPOLINE
+  #define NDS32_TLSDESC_TRAMPOLINE_SPEC \
+    " %{!mno-tlsdesc-trampoline:--mtlsdesc-trampoline}"
+#else
+  #define NDS32_TLSDESC_TRAMPOLINE_SPEC ""
+#endif
+
+#define TARGET_OS_CPP_BUILTINS()                \
+  do                                            \
+    {                                           \
+      GNU_USER_TARGET_OS_CPP_BUILTINS();           \
+    }                                           \
+  while (0)
+
+#define GLIBC_DYNAMIC_LINKER "/lib/ld.so.1"
+
+/* In the configure stage we may use options --enable-default-relax,
+   --enable-Os-default-ifc and --enable-Os-default-ex9.  They effect
+   the default spec of passing --relax, --mifc, and --mex9 to linker.
+   We use NDS32_RELAX_SPEC, NDS32_IFC_SPEC, and NDS32_EX9_SPEC
+   so that we can customize them conveniently.  */
+#define LINK_SPEC \
+ " %{G*}" \
+ " %{mbig-endian:-EB} %{mlittle-endian:-EL}" \
+ " %{shared:-shared} \
+  %{!shared: \
+    %{!static: \
+      %{rdynamic:-export-dynamic} \
+      -dynamic-linker " GNU_USER_DYNAMIC_LINKER "} \
+    %{static:-static}}" \
+  NDS32_RELAX_SPEC \
+  NDS32_TLSDESC_TRAMPOLINE_SPEC
+
+#define LINK_PIE_SPEC "%{pie:%{!fno-pie:%{!fno-PIE:%{!static:-pie}}}} "
+
+#define CPP_SPEC "%{pthread:-D_REENTRANT}"
+
+/* The SYNC operations are implemented as library functions, not
+   INSN patterns.  As a result, the HAVE defines for the patterns are
+   not defined.  We need to define them to generate the corresponding
+   __GCC_HAVE_SYNC_COMPARE_AND_SWAP_* and __GCC_ATOMIC_*_LOCK_FREE
+   defines.
+   Ref: https://sourceware.org/ml/libc-alpha/2014-09/msg00322.html  */
+#define HAVE_sync_compare_and_swapqi 1
+#define HAVE_sync_compare_and_swaphi 1
+#define HAVE_sync_compare_and_swapsi 1
diff --git a/gcc/config/nds32/nds32-elf.opt b/gcc/config/nds32/nds32-elf.opt
new file mode 100644
index 0000000..afe6aad
--- /dev/null
+++ b/gcc/config/nds32/nds32-elf.opt
@@ -0,0 +1,16 @@
+mcmodel=
+Target RejectNegative Joined Enum(nds32_cmodel_type) Var(nds32_cmodel_option) Init(CMODEL_MEDIUM)
+Specify the address generation strategy for code model.
+
+Enum
+Name(nds32_cmodel_type) Type(enum nds32_cmodel_type)
+Known cmodel types (for use with the -mcmodel= option):
+
+EnumValue
+Enum(nds32_cmodel_type) String(small) Value(CMODEL_SMALL)
+
+EnumValue
+Enum(nds32_cmodel_type) String(medium) Value(CMODEL_MEDIUM)
+
+EnumValue
+Enum(nds32_cmodel_type) String(large) Value(CMODEL_LARGE)
diff --git a/gcc/config/nds32/nds32-fp-as-gp.c b/gcc/config/nds32/nds32-fp-as-gp.c
index 1abad1d..26d2865 100644
--- a/gcc/config/nds32/nds32-fp-as-gp.c
+++ b/gcc/config/nds32/nds32-fp-as-gp.c
@@ -265,7 +265,8 @@ public:
   /* opt_pass methods: */
   bool gate (function *)
   {
-    return TARGET_16_BIT
+    return !TARGET_LINUX_ABI
+	   && TARGET_16_BIT
 	   && optimize_size;
   }
   unsigned int execute (function *) { return nds32_fp_as_gp (); }
diff --git a/gcc/config/nds32/nds32-linux.opt b/gcc/config/nds32/nds32-linux.opt
new file mode 100644
index 0000000..75ccd76
--- /dev/null
+++ b/gcc/config/nds32/nds32-linux.opt
@@ -0,0 +1,16 @@
+mcmodel=
+Target RejectNegative Joined Enum(nds32_cmodel_type) Var(nds32_cmodel_option) Init(CMODEL_LARGE)
+Specify the address generation strategy for code model.
+
+Enum
+Name(nds32_cmodel_type) Type(enum nds32_cmodel_type)
+Known cmodel types (for use with the -mcmodel= option):
+
+EnumValue
+Enum(nds32_cmodel_type) String(small) Value(CMODEL_SMALL)
+
+EnumValue
+Enum(nds32_cmodel_type) String(medium) Value(CMODEL_MEDIUM)
+
+EnumValue
+Enum(nds32_cmodel_type) String(large) Value(CMODEL_LARGE)
diff --git a/gcc/config/nds32/nds32.c b/gcc/config/nds32/nds32.c
index 1afd8a1..a0b6443 100644
--- a/gcc/config/nds32/nds32.c
+++ b/gcc/config/nds32/nds32.c
@@ -1698,6 +1698,9 @@ nds32_conditional_register_usage (void)
 {
   int regno;
 
+  if (TARGET_LINUX_ABI)
+    fixed_regs[TP_REGNUM] = 1;
+
   if (TARGET_HARD_FLOAT)
     {
       for (regno = NDS32_FIRST_FPR_REGNUM;
@@ -3120,21 +3123,30 @@ nds32_asm_file_start (void)
   fprintf (asm_out_file, "\t! This asm file is generated by compiler\n");
   fprintf (asm_out_file, "\t.flag\tverbatim\n");
 
-  if (TARGET_ICT_MODEL_LARGE)
-    fprintf (asm_out_file, "\t.ict_model\tlarge\n");
-  else
-    fprintf (asm_out_file, "\t.ict_model\tsmall\n");
-  /* Give assembler the size of each vector for interrupt handler.  */
-  fprintf (asm_out_file, "\t! This vector size directive is required "
-			 "for checking inconsistency on interrupt handler\n");
-  fprintf (asm_out_file, "\t.vec_size\t%d\n", nds32_isr_vector_size);
+  /* Insert directive for linker to distinguish object's ict flag.  */
+  if (!TARGET_LINUX_ABI)
+    {
+      if (TARGET_ICT_MODEL_LARGE)
+	fprintf (asm_out_file, "\t.ict_model\tlarge\n");
+      else
+	fprintf (asm_out_file, "\t.ict_model\tsmall\n");
+    }
+
+  /* We need to provide the size of each vector for interrupt handler
+     under elf toolchain.  */
+  if (!TARGET_LINUX_ABI)
+    {
+      fprintf (asm_out_file, "\t! This vector size directive is required "
+			     "for checking inconsistency on interrupt handler\n");
+      fprintf (asm_out_file, "\t.vec_size\t%d\n", nds32_isr_vector_size);
+    }
 
   /* If user enables '-mforce-fp-as-gp' or compiles programs with -Os,
      the compiler may produce 'la $fp,_FP_BASE_' instruction
      at prologue for fp-as-gp optimization.
      We should emit weak reference of _FP_BASE_ to avoid undefined reference
      in case user does not pass '--relax' option to linker.  */
-  if (TARGET_FORCE_FP_AS_GP || optimize_size)
+  if (!TARGET_LINUX_ABI && (TARGET_FORCE_FP_AS_GP || optimize_size))
     {
       fprintf (asm_out_file, "\t! This weak reference is required to do "
 			     "fp-as-gp link time optimization\n");
@@ -3270,6 +3282,11 @@ nds32_asm_file_end (void)
 {
   nds32_asm_file_end_for_isr ();
 
+  /* The NDS32 Linux stack is mapped non-executable by default, so add a
+     .note.GNU-stack section.  */
+  if (TARGET_LINUX_ABI)
+    file_end_indicate_exec_stack ();
+
   fprintf (asm_out_file, "\t! ------------------------------------\n");
 }
 
@@ -3497,7 +3514,7 @@ nds32_print_operand (FILE *stream, rtx x, int code)
     case SYMBOL_REF:
       output_addr_const (stream, x);
 
-      if (nds32_indirect_call_referenced_p (x))
+      if (!TARGET_LINUX_ABI && nds32_indirect_call_referenced_p (x))
 	fprintf (stream, "@ICT");
 
       break;
@@ -3912,6 +3929,9 @@ nds32_insert_attributes (tree decl, tree *attributes)
     {
       tree new_attrs = *attributes;
 
+      if (TARGET_LINUX_ABI)
+	error("cannot use indirect_call attribute under linux toolchain");
+
       if (lookup_attribute ("noinline", new_attrs) == NULL)
 	new_attrs = tree_cons (get_identifier ("noinline"), NULL, new_attrs);
       if (lookup_attribute ("noclone", new_attrs) == NULL)
@@ -4166,6 +4186,13 @@ nds32_expand_builtin (tree exp,
   return nds32_expand_builtin_impl (exp, target, subtarget, mode, ignore);
 }
 
+/* Implement TARGET_INIT_LIBFUNCS.  */
+static void
+nds32_init_libfuncs (void)
+{
+  if (TARGET_LINUX_ABI)
+    init_sync_libfuncs (UNITS_PER_WORD);
+}
 
 /* ------------------------------------------------------------------------ */
 
@@ -5758,6 +5785,9 @@ nds32_use_blocks_for_constant_p (machine_mode mode,
 
 /* Emulating TLS.  */
 
+#undef TARGET_HAVE_TLS
+#define TARGET_HAVE_TLS TARGET_LINUX_ABI
+
 
 /* Defining coprocessor specifics for MIPS targets.  */
 
@@ -5785,6 +5815,8 @@ nds32_use_blocks_for_constant_p (machine_mode mode,
 #undef TARGET_EXPAND_BUILTIN
 #define TARGET_EXPAND_BUILTIN nds32_expand_builtin
 
+#undef TARGET_INIT_LIBFUNCS
+#define TARGET_INIT_LIBFUNCS nds32_init_libfuncs
 
 #undef TARGET_USE_BLOCKS_FOR_CONSTANT_P
 #define TARGET_USE_BLOCKS_FOR_CONSTANT_P nds32_use_blocks_for_constant_p
diff --git a/gcc/config/nds32/nds32.h b/gcc/config/nds32/nds32.h
index 523492f..84fae7d 100644
--- a/gcc/config/nds32/nds32.h
+++ b/gcc/config/nds32/nds32.h
@@ -922,6 +922,14 @@ enum nds32_builtins
 
 #define TARGET_CONFIG_FPU_DEFAULT NDS32_CONFIG_FPU_2
 
+/* ------------------------------------------------------------------------ */
+
+#ifdef TARGET_DEFAULT_RELAX
+#  define NDS32_RELAX_SPEC " %{!mno-relax:--relax}"
+#else
+#  define NDS32_RELAX_SPEC " %{mrelax:--relax}"
+#endif
+
 #ifdef TARGET_DEFAULT_EXT_DSP
 #  define NDS32_EXT_DSP_SPEC " %{!mno-ext-dsp:-mext-dsp}"
 #else
@@ -963,34 +971,6 @@ enum nds32_builtins
   " %{mext-dsp:-mdsp-ext}" \
   " %{O|O1|O2|O3|Ofast:-O1;:-Os}"
 
-/* If user issues -mrelax, we need to pass '--relax' to linker.  */
-#define LINK_SPEC \
-  " %{mbig-endian:-EB} %{mlittle-endian:-EL}" \
-  " %{mrelax:--relax}"
-
-#define LIB_SPEC \
-  " -lc -lgloss"
-
-/* The option -mno-ctor-dtor can disable constructor/destructor feature
-   by applying different crt stuff.  In the convention, crt0.o is the
-   startup file without constructor/destructor;
-   crt1.o, crti.o, crtbegin.o, crtend.o, and crtn.o are the
-   startup files with constructor/destructor.
-   Note that crt0.o, crt1.o, crti.o, and crtn.o are provided
-   by newlib/mculib/glibc/ublic, while crtbegin.o and crtend.o are
-   currently provided by GCC for nds32 target.
-
-   For nds32 target so far:
-   If -mno-ctor-dtor, we are going to link
-   "crt0.o [user objects]".
-   If general cases, we are going to link
-   "crt1.o crtbegin1.o [user objects] crtend1.o".  */
-#define STARTFILE_SPEC \
-  " %{!mno-ctor-dtor:crt1.o%s;:crt0.o%s}" \
-  " %{!mno-ctor-dtor:crtbegin1.o%s}"
-#define ENDFILE_SPEC \
-  " %{!mno-ctor-dtor:crtend1.o%s}"
-
 /* The TARGET_BIG_ENDIAN_DEFAULT is defined if we
    configure gcc with --target=nds32be-* setting.
    Check gcc/config.gcc for more information.  */
@@ -1000,9 +980,11 @@ enum nds32_builtins
 #  define NDS32_ENDIAN_DEFAULT "mlittle-endian"
 #endif
 
-/* Currently we only have elf toolchain,
-   where -mcmodel=medium is always the default.  */
-#define NDS32_CMODEL_DEFAULT "mcmodel=medium"
+#if TARGET_ELF
+#  define NDS32_CMODEL_DEFAULT "mcmodel=medium"
+#else
+#  define NDS32_CMODEL_DEFAULT "mcmodel=large"
+#endif
 
 #define MULTILIB_DEFAULTS \
   { NDS32_ENDIAN_DEFAULT, NDS32_CMODEL_DEFAULT }
diff --git a/gcc/config/nds32/nds32.md b/gcc/config/nds32/nds32.md
index cf1ad9b..92e90dd 100644
--- a/gcc/config/nds32/nds32.md
+++ b/gcc/config/nds32/nds32.md
@@ -2221,7 +2221,7 @@
   [(set (match_operand:SI 0 "register_operand"          "=r")
 	(plus:SI (match_operand:SI 1 "register_operand"  "0")
 		 (pc)))]
-  "flag_pic"
+  "TARGET_LINUX_ABI || flag_pic"
   "add5.pc\t%0"
   [(set_attr "type"    "alu")
    (set_attr "length"    "4")]
diff --git a/gcc/config/nds32/nds32.opt b/gcc/config/nds32/nds32.opt
index 6f73f89..871ae1e 100644
--- a/gcc/config/nds32/nds32.opt
+++ b/gcc/config/nds32/nds32.opt
@@ -151,7 +151,7 @@ Target Report Mask(RELAX_HINT)
 Insert relax hint for linker to do relaxation.
 
 mvh
-Target Report Mask(VH)
+Target Report Mask(VH) Condition(!TARGET_LINUX_ABI)
 Enable Virtual Hosting support.
 
 misr-vector-size=
@@ -185,23 +185,6 @@ Enum(nds32_arch_type) String(v3f) Value(ARCH_V3F)
 EnumValue
 Enum(nds32_arch_type) String(v3s) Value(ARCH_V3S)
 
-mcmodel=
-Target RejectNegative Joined Enum(nds32_cmodel_type) Var(nds32_cmodel_option) Init(CMODEL_LARGE)
-Specify the address generation strategy for code model.
-
-Enum
-Name(nds32_cmodel_type) Type(enum nds32_cmodel_type)
-Known cmodel types (for use with the -mcmodel= option):
-
-EnumValue
-Enum(nds32_cmodel_type) String(small) Value(CMODEL_SMALL)
-
-EnumValue
-Enum(nds32_cmodel_type) String(medium) Value(CMODEL_MEDIUM)
-
-EnumValue
-Enum(nds32_cmodel_type) String(large) Value(CMODEL_LARGE)
-
 mcpu=
 Target RejectNegative Joined Enum(nds32_cpu_type) Var(nds32_cpu_option) Init(CPU_N9)
 Specify the cpu for pipeline model.
diff --git a/gcc/config/nds32/t-elf b/gcc/config/nds32/t-elf
new file mode 100644
index 0000000..3401dae
--- /dev/null
+++ b/gcc/config/nds32/t-elf
@@ -0,0 +1,42 @@
+# The multilib settings of Andes NDS32 cpu for GNU compiler
+# Copyright (C) 2012-2018 Free Software Foundation, Inc.
+# Contributed by Andes Technology Corporation.
+#
+# 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/>.
+
+# We also define a macro MULTILIB_DEFAULTS in nds32.h that tells the
+# driver program which options are defaults for this target and thus
+# do not need to be handled specially.
+MULTILIB_OPTIONS += mcmodel=small/mcmodel=medium/mcmodel=large mvh
+
+ifneq ($(filter graywolf,$(TM_MULTILIB_CONFIG)),)
+MULTILIB_OPTIONS += mcpu=graywolf
+endif
+
+ifneq ($(filter dsp,$(TM_MULTILIB_CONFIG)),)
+MULTILIB_OPTIONS += mext-dsp
+endif
+
+ifneq ($(filter zol,$(TM_MULTILIB_CONFIG)),)
+MULTILIB_OPTIONS += mext-zol
+endif
+
+ifneq ($(filter v3m+,$(TM_MULTILIB_CONFIG)),)
+MULTILIB_OPTIONS += march=v3m+
+endif
+
+# ------------------------------------------------------------------------
diff --git a/gcc/config/nds32/t-linux b/gcc/config/nds32/t-linux
new file mode 100644
index 0000000..33328f6
--- /dev/null
+++ b/gcc/config/nds32/t-linux
@@ -0,0 +1,26 @@
+# The multilib settings of Andes NDS32 cpu for GNU compiler
+# Copyright (C) 2012-2018 Free Software Foundation, Inc.
+# Contributed by Andes Technology Corporation.
+#
+# 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/>.
+
+# We also define a macro MULTILIB_DEFAULTS in nds32.h that tells the
+# driver program which options are defaults for this target and thus
+# do not need to be handled specially.
+MULTILIB_OPTIONS +=
+
+# ------------------------------------------------------------------------