[PATCH] Add support for ia16

[Andrew Jenner <andrew at codesourcery dot com>]

I've posted patches to gcc-patches for adding an ia16 (16-bit x86) port 
to GCC (see https://gcc.gnu.org/ml/gcc-patches/2017-04/msg00009.html). 
Some binutils changes are required to make this work, attached.

When the port was originally created by Rask Ingemann Lambertsen 10 
years ago, he made it work by symlinking the ia16-* binutils programs to 
the corresponding i386-* programs. With this patch, this hack is not 
necessary - real ia16-* binutils programs are built using the same 
sources as i386.

Okay to commit?

Thanks,

Andrew


2017-04-01  Andrew Jenner  <andrew@codesourcery.com>

	* config.sub: Handle ia16 in $basic_machine.

	bfd/
	* config.bfd: Handle ia16.

	gas/
	* configure.tgt: Handle ia16.

	ld/
	* configure.tgt: Handle ia16.

Index: gas/configure.tgt
===================================================================
--- gas/configure.tgt	(revision 475333)
+++ gas/configure.tgt	(revision 475423)
@@ -62,6 +62,7 @@ case ${cpu} in
   fido)			cpu_type=m68k ;;
   hppa*)		cpu_type=hppa ;;
   i[3-7]86)		cpu_type=i386 arch=i386;;
+  ia16)			cpu_type=i386 arch=i386;;
   ia64)			cpu_type=ia64 ;;
   ip2k)			cpu_type=ip2k endian=big ;;
   iq2000)		cpu_type=iq2000 endian=big ;;
@@ -289,6 +290,8 @@ case ${generic_target} in

   i960-*-elf*)				fmt=elf ;;

+  ia16-*-elf*)				fmt=elf ;;
+
   ia64-*-elf*)				fmt=elf ;;
   ia64-*-*vms*)				fmt=elf em=vms ;;
   ia64-*-aix*)				fmt=elf em=ia64aix ;;
Index: config.sub
===================================================================
--- config.sub	(revision 475333)
+++ config.sub	(revision 475423)
@@ -2,7 +2,7 @@
 # Configuration validation subroutine script.
 #   Copyright 1992-2016 Free Software Foundation, Inc.

-timestamp='2016-01-11'
+timestamp='2017-03-28'

 # This file is free software; you can redistribute it and/or modify it
 # under the terms of the GNU General Public License as published by
@@ -263,7 +263,7 @@ case $basic_machine in
 	| fido | fr30 | frv | ft32 \
 	| h8300 | h8500 | hppa | hppa1.[01] | hppa2.0 | hppa2.0[nw] | hppa64 \
 	| hexagon \
-	| i370 | i860 | i960 | ia64 \
+	| i370 | i860 | i960 | ia64 | ia16 \
 	| ip2k | iq2000 \
 	| k1om \
 	| le32 | le64 \
Index: ld/configure.tgt
===================================================================
--- ld/configure.tgt	(revision 475333)
+++ ld/configure.tgt	(revision 475423)
@@ -399,6 +399,7 @@ i960-intel-nindy)	targ_emul=gld960 ;;
 i960-*-rtems*)		targ_emul=gld960coff ;;
 i960-*-elf*)		targ_emul=elf32_i960
 			;;
+ia16-*-elf*)		targ_emul=elf_i386 targ_extra_emuls=i386msdos ;;
 ia64-*-elf*)		targ_emul=elf64_ia64 ;;
 ia64-*-freebsd* | ia64-*-kfreebsd*-gnu)
 		        targ_emul=elf64_ia64_fbsd
Index: bfd/config.bfd
===================================================================
--- bfd/config.bfd	(revision 475333)
+++ bfd/config.bfd	(revision 475423)
@@ -108,6 +108,7 @@ fido*)		 targ_archs=bfd_m68k_arch ;;
 hppa*)		 targ_archs=bfd_hppa_arch ;;
 i[3-7]86)	 targ_archs=bfd_i386_arch ;;
 i370)		 targ_archs=bfd_i370_arch ;;
+ia16)		 targ_archs=bfd_i386_arch ;;
 lm32)	         targ_archs=bfd_lm32_arch ;;
 m6811*|m68hc11*) targ_archs="bfd_m68hc11_arch bfd_m68hc12_arch bfd_m9s12x_arch bfd_m9s12xg_arch" ;;
 m6812*|m68hc12*) targ_archs="bfd_m68hc12_arch bfd_m68hc11_arch bfd_m9s12x_arch bfd_m9s12xg_arch" ;;
@@ -823,6 +824,11 @@ case "${targ}" in
     targ_selvecs="icoff_le_vec icoff_be_vec"
     ;;

+  ia16-*-elf)
+    targ_defvec=i386_elf32_vec
+    targ_selvecs="i386_msdos_vec i386_aout_vec"
+    ;;
+
   ip2k-*-elf)
     targ_defvec=ip2k_elf32_vec
     ;;