[PATCH 2/2] x86: break gas dependency on libopcodes

[Jan Beulich <jbeulich@suse.com>]

The only item gas still consumes from libopcodes is i386_seg_prefixes[],
which again is used by gas alone. Move it into the assembler, allowing
to remove the linking in of libopcodes.

To compensate, tie table generation in opcodes/ to the building of
i386-dis.o, despite the file not really depending on the generated data.
---
RFC: Is there a better way to specify extra dependencies, such that
     table generation and compilation of i386-dis.c could be kept
     separate (and hence processable in parallel)?

--- a/gas/config/tc-i386.c
+++ b/gas/config/tc-i386.c
@@ -445,6 +445,16 @@ struct _i386_insn
 
 typedef struct _i386_insn i386_insn;
 
+/* To be indexed by segment register number.  */
+static const unsigned char i386_seg_prefixes[] = {
+  ES_PREFIX_OPCODE,
+  CS_PREFIX_OPCODE,
+  SS_PREFIX_OPCODE,
+  DS_PREFIX_OPCODE,
+  FS_PREFIX_OPCODE,
+  GS_PREFIX_OPCODE
+};
+
 /* Link RC type with corresponding string, that'll be looked for in
    asm.  */
 struct RC_name
--- a/gas/configure
+++ b/gas/configure
@@ -12263,7 +12263,7 @@ _ACEOF
 
     # Do we need the opcodes library?
     case ${cpu_type} in
-      vax | tic30)
+      vax | tic30 | i386)
 	;;
 
       *)
--- a/gas/configure.ac
+++ b/gas/configure.ac
@@ -420,7 +420,7 @@ changequote([,])dnl
 
     # Do we need the opcodes library?
     case ${cpu_type} in
-      vax | tic30)
+      vax | tic30 | i386)
 	;;
 
       *)
--- a/opcodes/Makefile.am
+++ b/opcodes/Makefile.am
@@ -162,7 +162,6 @@ TARGET32_LIBOPCODES_CFILES = \
 	h8300-dis.c \
 	hppa-dis.c \
 	i386-dis.c \
-	i386-opc.c \
 	ip2k-asm.c \
 	ip2k-desc.c \
 	ip2k-dis.c \
@@ -564,7 +563,7 @@ $(srcdir)/i386%tbl.h $(srcdir)/i386%init
 
 # While not really dependencies, specify i386-{init,tbl}.h here as well to
 # make sure they are re-generated as necessary.
-i386-opc.lo: $(srcdir)/i386-tbl.h $(srcdir)/i386-init.h
+i386-dis.lo: $(srcdir)/i386-tbl.h $(srcdir)/i386-init.h
 
 ia64-gen$(EXEEXT_FOR_BUILD): ia64-gen.o $(BUILD_LIB_DEPS)
 	$(AM_V_CCLD)$(LINK_FOR_BUILD) ia64-gen.o $(BUILD_LIBS)
--- a/opcodes/Makefile.in
+++ b/opcodes/Makefile.in
@@ -554,7 +554,6 @@ TARGET32_LIBOPCODES_CFILES = \
 	h8300-dis.c \
 	hppa-dis.c \
 	i386-dis.c \
-	i386-opc.c \
 	ip2k-asm.c \
 	ip2k-desc.c \
 	ip2k-dis.c \
@@ -947,7 +946,6 @@ distclean-compile:
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/h8300-dis.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/hppa-dis.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/i386-dis.Plo@am__quote@
-@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/i386-opc.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/ia64-dis.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/ia64-opc.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/ip2k-asm.Plo@am__quote@
@@ -1539,7 +1537,7 @@ $(srcdir)/i386%tbl.h $(srcdir)/i386%init
 
 # While not really dependencies, specify i386-{init,tbl}.h here as well to
 # make sure they are re-generated as necessary.
-i386-opc.lo: $(srcdir)/i386-tbl.h $(srcdir)/i386-init.h
+i386-dis.lo: $(srcdir)/i386-tbl.h $(srcdir)/i386-init.h
 
 ia64-gen$(EXEEXT_FOR_BUILD): ia64-gen.o $(BUILD_LIB_DEPS)
 	$(AM_V_CCLD)$(LINK_FOR_BUILD) ia64-gen.o $(BUILD_LIBS)
--- a/opcodes/i386-opc.c
+++ /dev/null
@@ -1,33 +0,0 @@
-/* Intel 80386 opcode table
-   Copyright (C) 2007-2022 Free Software Foundation, Inc.
-
-   This file is part of the GNU opcodes library.
-
-   This library 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.
-
-   It 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 this program; if not, write to the Free Software
-   Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
-   MA 02110-1301, USA.  */
-
-#include "sysdep.h"
-#include "libiberty.h"
-#include "i386-opc.h"
-
-/* To be indexed by segment register number.  */
-const unsigned char i386_seg_prefixes[] = {
-  ES_PREFIX_OPCODE,
-  CS_PREFIX_OPCODE,
-  SS_PREFIX_OPCODE,
-  DS_PREFIX_OPCODE,
-  FS_PREFIX_OPCODE,
-  GS_PREFIX_OPCODE
-};
--- a/opcodes/i386-opc.h
+++ b/opcodes/i386-opc.h
@@ -1003,5 +1003,3 @@ typedef struct
 #define Dw2Inval (-1)
 }
 reg_entry;
-
-extern const unsigned char i386_seg_prefixes[6];