Support on-demand global register allocation by passing on

	base-plus-offset relocs to the linker.
	* config/tc-mmix.c: Tweak and fix typos in comments.
 	(allocate_undefined_gregs_in_linker): New variable.
	(OPTION_LINKER_ALLOCATED_GREGS): New option macro.
	(md_longopts): Add --linker-allocated-gregs.
	(md_parse_option) <case 'x'>: Imply --linker-allocated-gregs.
	<case OPTION_LINKER_ALLOCATED_GREGS>: New.
	(md_show_usage): Update text for -x.  Add text for
	--linker-allocated-gregs.
	(tc_gen_reloc): Derive default value for addend from val and
	baddsy.  Use addsec and bfd_is_abs_section in more places.  Don't
	emit error for BFD_RELOC_MMIX_BASE_PLUS_OFFSET without suitable
	GREG if allocate_undefined_gregs_in_linker.
	* doc/as.texinfo (Overview) <Target MMIX options>: Add
	--linker-allocated-gregs.
	* doc/c-mmix.texi (MMIX-Opts): Add blurb about
	--linker-allocated-gregs.  Mention that it's implied by -x.
	(MMIX-Pseudos) <GREG>: Mention when and how a GREG can be omitted.
	(MMIX-mmixal): Clarify dated comparison and location of MMIXware.

	* config/tc-mmix.h (md_parse_name): Use ISUPPER, not isupper.

2 files changed, 23 insertions, 10 deletions

diff --git a/gas/doc/as.texinfo b/gas/doc/as.texinfo
index 3d7fef5..6d04ac4 100644
--- a/gas/doc/as.texinfo
+++ b/gas/doc/as.texinfo
@@ -1,6 +1,6 @@
 \input texinfo @c                               -*-Texinfo-*-
 @c  Copyright 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
-@c  2001
+@c  2001, 2002
 @c  Free Software Foundation, Inc.
 @c UPDATE!!  On future updates--
 @c   (1)   check for new machine-dep cmdline options in
@@ -127,7 +127,7 @@ END-INFO-DIR-ENTRY
 This file documents the GNU Assembler "@value{AS}".
 
 @c man begin COPYRIGHT
-Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000, 2001 Free Software Foundation, Inc.
+Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000, 2001, 2002 Free Software Foundation, Inc.
 
 Permission is granted to copy, distribute and/or modify this document
 under the terms of the GNU Free Documentation License, Version 1.1
@@ -180,7 +180,7 @@ done.
 @end tex
 
 @vskip 0pt plus 1filll
-Copyright @copyright{} 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000, 2001 Free Software Foundation, Inc.
+Copyright @copyright{} 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000, 2001, 2002 Free Software Foundation, Inc.
 
       Permission is granted to copy, distribute and/or modify this document
       under the terms of the GNU Free Documentation License, Version 1.1
@@ -354,6 +354,7 @@ gcc(1), ld(1), and the Info entries for @file{binutils} and @file{ld}.
    [@b{--fixed-special-register-names}] [@b{--globalize-symbols}]
    [@b{--gnu-syntax}] [@b{--relax}] [@b{--no-predefined-symbols}]
    [@b{--no-expand}] [@b{--no-merge-gregs}] [@b{-x}]
+   [@b{--linker-allocated-gregs}]
 @end ifset
 @ifset PDP11
 
diff --git a/gas/doc/c-mmix.texi b/gas/doc/c-mmix.texi
index dd18765..e3622ac 100644
--- a/gas/doc/c-mmix.texi
+++ b/gas/doc/c-mmix.texi
@@ -1,4 +1,4 @@
-@c Copyright 2001 Free Software Foundation, Inc.
+@c Copyright 2001, 2002 Free Software Foundation, Inc.
 @c This is part of the GAS manual.
 @c For copying conditions, see the file as.texinfo.
 @c MMIX description by Hans-Peter Nilsson, hp@bitrange.com
@@ -79,7 +79,15 @@ is specified, and assembly fails otherwise, when an instruction needs to
 be expanded.  It needs to be kept in mind that @code{mmixal} is both an
 assembler and linker, while @code{@value{AS}} will expand instructions
 that at link stage can be contracted.  (Though linker relaxation isn't yet
-implemented in @code{@value{LD}}.)
+implemented in @code{@value{LD}}.)  The option @samp{-x} also imples
+@samp{--linker-allocated-gregs}.
+
+@cindex @samp{--linker-allocated-gregs} command line option, MMIX
+Usually a two-operand-expression (@pxref{GREG-base}) without a matching
+@samp{GREG} directive is treated as an error by @code{@value{AS}}.  When
+the option @samp{--linker-allocated-gregs} is in effect, they are instead
+passed through to the linker, which will allocate as many global registers
+as is needed.
 
 @node MMIX-Expand
 @section Instruction expansion
@@ -381,7 +389,10 @@ Global registers allocated with this directive are allocated in order
 higher-to-lower within a file.  Other than that, the exact order of
 register allocation and elimination is undefined.  For example, the order
 is undefined when more than one file with such directives are linked
-together.
+together.  With the options @samp{-x} and @samp{--linker-allocated-gregs},
+@samp{GREG} directives for two-operand cases like the one mentioned above
+can be omitted.  Sufficient global registers will then be allocated by the
+linker.
 
 @item BYTE
 @cindex assembler directive BYTE, MMIX
@@ -544,10 +555,11 @@ upper-case characters.
 
 There's no unicode support.
 
-The following is a list of programs in
-@url{http://www-cs-faculty.stanford.edu/~knuth/mmix-news.html} dated
-2001-08-25 (md5sum c393470cfc86fac040487d22d2bf0172) that assemble with
-@code{mmixal} but do not assemble with @code{@value{AS}}:
+The following is a list of programs in @samp{mmix.tar.gz}, available at
+@url{http://www-cs-faculty.stanford.edu/~knuth/mmix-news.html}, last
+checked with the version dated 2001-08-25 (md5sum
+c393470cfc86fac040487d22d2bf0172) that assemble with @code{mmixal} but do
+not assemble with @code{@value{AS}}:
 
 @table @code
 @item silly.mms