From 973eb3402f7b79ba3444177887be54562a276841 Mon Sep 17 00:00:00 2001 From: Hans-Peter Nilsson Date: Fri, 1 Feb 2002 08:09:47 +0000 Subject: [PATCH] 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) : Imply --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) : 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) : 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. --- gas/ChangeLog | 25 ++++++++++++++ gas/config/tc-mmix.c | 80 +++++++++++++++++++++++++++----------------- gas/config/tc-mmix.h | 4 +-- gas/doc/as.texinfo | 7 ++-- gas/doc/c-mmix.texi | 26 ++++++++++---- 5 files changed, 100 insertions(+), 42 deletions(-) diff --git a/gas/ChangeLog b/gas/ChangeLog index fa1a2fdbb9..e0c8b438f7 100644 --- a/gas/ChangeLog +++ b/gas/ChangeLog @@ -1,3 +1,28 @@ +2002-02-01 Hans-Peter Nilsson + + 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) : Imply --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) : 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) : 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. + 2002-02-01 Alan Modra * Makefile.am: Run "make dep-am" diff --git a/gas/config/tc-mmix.c b/gas/config/tc-mmix.c index fcd7f1e3b0..e396027c70 100644 --- a/gas/config/tc-mmix.c +++ b/gas/config/tc-mmix.c @@ -1,5 +1,5 @@ /* tc-mmix.c -- Assembler for Don Knuth's MMIX. - Copyright (C) 2001 Free Software Foundation. + Copyright (C) 2001, 2002 Free Software Foundation. This file is part of GAS, the GNU Assembler. @@ -154,11 +154,15 @@ static int warn_on_expansion = 1; /* Should we merge non-zero GREG register definitions? */ static int merge_gregs = 1; +/* Should we pass on undefined BFD_RELOC_MMIX_BASE_PLUS_OFFSET relocs + (missing suitable GREG definitions) to the linker? */ +static int allocate_undefined_gregs_in_linker = 0; + /* Should we emit built-in symbols? */ static int predefined_syms = 1; -/* Should we anything but the listed special register name (e.g. equated - symbols)? */ +/* Should we allow anything but the listed special register name + (e.g. equated symbols)? */ static int equated_spec_regs = 1; /* Do we require standard GNU syntax? */ @@ -185,6 +189,7 @@ struct option md_longopts[] = #define OPTION_GNU_SYNTAX (OPTION_NOSYMS + 1) #define OPTION_GLOBALIZE_SYMBOLS (OPTION_GNU_SYNTAX + 1) #define OPTION_FIXED_SPEC_REGS (OPTION_GLOBALIZE_SYMBOLS + 1) +#define OPTION_LINKER_ALLOCATED_GREGS (OPTION_FIXED_SPEC_REGS + 1) {"linkrelax", no_argument, NULL, OPTION_RELAX}, {"no-expand", no_argument, NULL, OPTION_NOEXPAND}, {"no-merge-gregs", no_argument, NULL, OPTION_NOMERGEGREG}, @@ -193,6 +198,8 @@ struct option md_longopts[] = {"globalize-symbols", no_argument, NULL, OPTION_GLOBALIZE_SYMBOLS}, {"fixed-special-register-names", no_argument, NULL, OPTION_FIXED_SPEC_REGS}, + {"linker-allocated-gregs", no_argument, NULL, + OPTION_LINKER_ALLOCATED_GREGS}, {NULL, no_argument, NULL, 0} }; @@ -621,6 +628,7 @@ md_parse_option (c, arg) { case 'x': warn_on_expansion = 0; + allocate_undefined_gregs_in_linker = 1; break; case OPTION_RELAX: @@ -653,6 +661,10 @@ md_parse_option (c, arg) equated_spec_regs = 0; break; + case OPTION_LINKER_ALLOCATED_GREGS: + allocate_undefined_gregs_in_linker = 1; + break; + default: return 0; } @@ -685,9 +697,13 @@ md_show_usage (stream) fprintf (stream, _("\ -no-merge-gregs Do not merge GREG definitions with nearby values.\n")); fprintf (stream, _("\ + -linker-allocated-gregs If there's no suitable GREG definition for the\ + operands of an instruction, let the linker resolve.\n")); + fprintf (stream, _("\ -x Do not warn when an operand to GETA, a branch,\n\ PUSHJ or JUMP is not known to be within range.\n\ - The linker will catch any errors.\n")); + The linker will catch any errors. Implies\n\ + -linker-allocated-gregs.")); } /* Step to end of line, but don't step over the end of the line. */ @@ -1031,10 +1047,10 @@ md_assemble (str) current_fb_label = -1; } - /* We also assume that the length of the instruction is determinable - from the first format character. Currently *all* the information is - in the first character. We need a self-contained frag since we want - the relocation to point to the instruction, not the variant part. */ + /* We also assume that the length of the instruction is at least 4, the + size of an unexpanded instruction. We need a self-contained frag + since we want the relocation to point to the instruction, not the + variant part. */ opcodep = frag_more (4); mmix_opcode_frag = opc_fragP = frag_now; @@ -2577,8 +2593,8 @@ tc_gen_reloc (section, fixP) char *buf = fixP->fx_where + fixP->fx_frag->fr_literal; symbolS *addsy = fixP->fx_addsy; asection *addsec = addsy == NULL ? NULL : S_GET_SEGMENT (addsy); - bfd_vma addend = fixP->fx_offset; asymbol *baddsy = addsy != NULL ? symbol_get_bfdsym (addsy) : NULL; + bfd_vma addend = val - (baddsy == NULL ? 0 : bfd_asymbol_value (baddsy)); /* A single " LOCAL expression" in the wrong section will not work when linking to MMO; relocations for zero-content sections are then @@ -2608,8 +2624,7 @@ tc_gen_reloc (section, fixP) case BFD_RELOC_8: code = fixP->fx_r_type; - if (addsy == NULL - || bfd_is_abs_section (S_GET_SEGMENT (addsy))) + if (addsy == NULL || bfd_is_abs_section (addsec)) { /* Resolve this reloc now, as md_apply_fix3 would have done (not called if -linkrelax). There is no point in keeping a reloc @@ -2658,7 +2673,7 @@ tc_gen_reloc (section, fixP) register contents section (that is, to a register), then we can't resolve the relocation here. */ if (addsy != NULL - && (bfd_is_und_section (S_GET_SEGMENT (addsy)) + && (bfd_is_und_section (addsec) || strcmp (bfd_get_section_name (addsec->owner, addsec), MMIX_REG_CONTENTS_SECTION_NAME) == 0)) { @@ -2672,14 +2687,13 @@ tc_gen_reloc (section, fixP) && (S_GET_SEGMENT (addsy) != real_reg_section || val > 255 || val < 0) - && ! bfd_is_abs_section (S_GET_SEGMENT (addsy))) + && ! bfd_is_abs_section (addsec)) goto badop; /* Set the "immediate" bit of the insn if this relocation is to Z field when the value is a numeric value, i.e. not a register. */ if ((fixP->fx_where & 3) == 3 - && (addsy == NULL - || S_GET_SEGMENT (addsy) == absolute_section)) + && (addsy == NULL || bfd_is_abs_section (addsec))) buf[-3] |= IMM_OFFSET_BIT; buf[0] = val; @@ -2687,8 +2701,8 @@ tc_gen_reloc (section, fixP) case BFD_RELOC_MMIX_BASE_PLUS_OFFSET: if (addsy != NULL - && strcmp (bfd_get_section_name (addsec->owner, addsec), - MMIX_REG_CONTENTS_SECTION_NAME) == 0) + && strcmp (bfd_get_section_name (addsec->owner, addsec), + MMIX_REG_CONTENTS_SECTION_NAME) == 0) { /* This changed into a register; the relocation is for the register-contents section. The constant part remains zero. */ @@ -2701,16 +2715,14 @@ tc_gen_reloc (section, fixP) If we encounter any other defined symbol, then we must find a suitable register and emit a reloc. */ - if (addsy == NULL - || S_GET_SEGMENT (addsy) != real_reg_section) + if (addsy == NULL || addsec != real_reg_section) { struct mmix_symbol_gregs *gregs; struct mmix_symbol_greg_fixes *fix; if (S_IS_DEFINED (addsy)) { - if (! symbol_section_p (addsy) - && ! bfd_is_abs_section (S_GET_SEGMENT (addsy))) + if (! symbol_section_p (addsy) && ! bfd_is_abs_section (addsec)) as_fatal (_("internal: BFD_RELOC_MMIX_BASE_PLUS_OFFSET not resolved to section")); /* If this is an absolute symbol sufficiently near @@ -2720,7 +2732,7 @@ tc_gen_reloc (section, fixP) comparisons. */ if (lowest_data_loc != (bfd_vma) -1 && (bfd_vma) val + 256 > lowest_data_loc - && bfd_is_abs_section (S_GET_SEGMENT (addsy))) + && bfd_is_abs_section (addsec)) { val -= (offsetT) lowest_data_loc; addsy = section_symbol (data_section); @@ -2728,7 +2740,7 @@ tc_gen_reloc (section, fixP) /* Likewise text section. */ else if (lowest_text_loc != (bfd_vma) -1 && (bfd_vma) val + 256 > lowest_text_loc - && bfd_is_abs_section (S_GET_SEGMENT (addsy))) + && bfd_is_abs_section (addsec)) { val -= (offsetT) lowest_text_loc; addsy = section_symbol (text_section); @@ -2738,8 +2750,7 @@ tc_gen_reloc (section, fixP) gregs = *symbol_get_tc (addsy); /* If that symbol does not have any associated GREG definitions, - we can't do anything. FIXME: implement allocate-on-demand in - the linker. */ + we can't do anything. */ if (gregs == NULL || (fix = bsearch (&val, gregs->greg_fixes, gregs->n_gregs, sizeof (gregs->greg_fixes[0]), @@ -2750,8 +2761,17 @@ tc_gen_reloc (section, fixP) before the address we want. */ || fix->offs + 255 < val) { - as_bad_where (fixP->fx_file, fixP->fx_line, - _("no suitable GREG definition for operands")); + /* We can either let the linker allocate GREGs + automatically, or emit an error. */ + if (allocate_undefined_gregs_in_linker) + { + /* The values in baddsy and addend are right. */ + code = fixP->fx_r_type; + break; + } + else + as_bad_where (fixP->fx_file, fixP->fx_line, + _("no suitable GREG definition for operands")); return NULL; } else @@ -2781,7 +2801,7 @@ tc_gen_reloc (section, fixP) case BFD_RELOC_MMIX_REG: if (addsy != NULL - && (bfd_is_und_section (S_GET_SEGMENT (addsy)) + && (bfd_is_und_section (addsec) || strcmp (bfd_get_section_name (addsec->owner, addsec), MMIX_REG_CONTENTS_SECTION_NAME) == 0)) { @@ -2790,10 +2810,10 @@ tc_gen_reloc (section, fixP) } if (addsy != NULL - && (S_GET_SEGMENT (addsy) != real_reg_section + && (addsec != real_reg_section || val > 255 || val < 0) - && ! bfd_is_und_section (S_GET_SEGMENT (addsy))) + && ! bfd_is_und_section (addsec)) /* Drop through to error message. */ ; else diff --git a/gas/config/tc-mmix.h b/gas/config/tc-mmix.h index e0b6f492b6..53d4df23f5 100644 --- a/gas/config/tc-mmix.h +++ b/gas/config/tc-mmix.h @@ -1,5 +1,5 @@ /* tc-mmix.h -- Header file for tc-mmix.c. - Copyright (C) 2001 Free Software Foundation, Inc. + Copyright (C) 2001, 2002 Free Software Foundation, Inc. Written by Hans-Peter Nilsson (hp@bitrange.com). This file is part of GAS, the GNU Assembler. @@ -75,7 +75,7 @@ extern int mmix_gnu_syntax; && (name[0] == '@' \ ? (! is_part_of_name (name[1]) \ && mmix_current_location (current_location, exp)) \ - : ((name[0] == ':' || isupper (name[0])) \ + : ((name[0] == ':' || ISUPPER (name[0])) \ && mmix_parse_predefined_name (name, exp)))) extern char *mmix_prefix_name PARAMS ((char *)); diff --git a/gas/doc/as.texinfo b/gas/doc/as.texinfo index 3d7fef5dc1..6d04ac44ff 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 dd18765d2a..e3622ac64f 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 -- 2.34.1