binutils-gdb/gas/config/obj-ecoff.c
Maciej W. Rozycki 37f9ec62db GAS: Add ECOFF `.aent' pseudo-op support
Implement the ECOFF `.aent' pseudo-op for ECOFF-style `.mdebug' section
support with ELF objects and, for consistency, also with ECOFF objects.
This is so that the same MIPS source can be assembled without and with
`.mdebug' section generation enabled.

Taking the `gas/testsuite/gas/mips/aent.s' test case source as an
example and the `mips-linux' target we have:

$ as -o aent.o aent.s
$ as -mdebug -o aent.o aent.s
aent.s: Assembler messages:
aent.s:10: Error: unknown pseudo-op: `.aent'
$

because for the !ECOFF_DEBUGGING case (which is the default) the
pseudo-op is already handled by the MIPS backend with `s_mips_ent',
however no handler is present for the opposite case.

For the MIPS target this is a functional regression introduced with
commit ecb4347ade ("Last take: approval for MIPS_STABS_ELF killing"),
<https://sourceware.org/ml/binutils/2002-06/msg00443.html>, where
support for the `.mdebug' section was added along with its associated
`-mdebug'/`-no-mdebug' command-line options, bringing an inconsistency
between the assembly syntax supported for each of these options as far
as the `.aent' pseudo-op is concerned.

Assembly language documentation available describes the pseudo-op
respectively as follows[1]:

"
.aent name, symno Sets an alternate entry point for the current
                  procedure.  Use this information when you want
                  to generate information for the debugger.  It must
                  appear inside an .ent/.end pair."

and[2]:

"
.aent name [,symno]
     Sets an alternate entry point for the current procedure.  Use this
     information when you want to generate information for the debugger.
     This directive must appear between a pair of .ent and .end directives.
     (The optional symno is for compiler use only.  It refers to a dense
     number in a .T file (symbol table).)"

Copy the approach from `s_mips_ent' then and add `.aent' support to the
`.ent' pseudo-op handler shared between the ELF and ECOFF object file
format backends, by setting BSF_FUNCTION for the symbol requested.

References:

[1] "MIPSpro Assembly Language Programmer's Guide", Silicon Graphics,
    Inc., Document Number 007-2418-004, Section 8.1 "Op-Codes", p. 96
    <http://techpubs.sgi.com/library/manuals/2000/007-2418-004/pdf/007-2418-004.pdf>

[2] "Digital UNIX Assembly Language Programmer's Guide", Digital
    Equipment Corporation, Order Number: AA-PS31D-TE, March 1996,
    Chapter 5 "Assembler Directives", p. 5-2
    <http://h41361.www4.hpe.com/docs/base_doc/DOCUMENTATION/V40G_PDF/APS31DTE.PDF>

	gas/
	* ecoff.c (ecoff_directive_ent, add_procedure): Handle `.aent'.
	* config/obj-ecoff.c (obj_pseudo_table): Add "aent" entry.
	* config/obj-elf.c (ecoff_debug_pseudo_table): Likewise.
	* testsuite/gas/mips/aent-2.d: New test.
	* testsuite/gas/mips/aent-mdebug.d: New test.
	* testsuite/gas/mips/aent-mdebug-2.d: New test.
	* testsuite/gas/mips/mips.exp: Run the new tests.
2017-02-17 21:29:11 +00:00

321 lines
9.8 KiB
C

/* ECOFF object file format.
Copyright (C) 1993-2017 Free Software Foundation, Inc.
Contributed by Cygnus Support.
This file was put together by Ian Lance Taylor <ian@cygnus.com>.
This file is part of GAS.
GAS 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.
GAS 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 GAS; see the file COPYING. If not, write to the Free
Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
02110-1301, USA. */
#define OBJ_HEADER "obj-ecoff.h"
#include "as.h"
#include "coff/internal.h"
#include "bfd/libcoff.h"
#include "bfd/libecoff.h"
/* Almost all of the ECOFF support is actually in ecoff.c in the main
gas directory. This file mostly just arranges to call that one at
the right times. */
/* Set section VMAs and GP values before reloc processing. */
void
ecoff_frob_file_before_fix (void)
{
bfd_vma addr;
asection *sec;
/* Set the section VMA values. We force the .sdata and .sbss
sections to the end to ensure that their VMA addresses are close
together so that the GP register can address both of them. We
put the .bss section after the .sbss section.
Also, for the Alpha, we must sort the sections, to make sure they
appear in the output file in the correct order. (Actually, maybe
this is a job for BFD. But the VMAs computed would be out of
whack if we computed them given our initial, random ordering.
It's possible that that wouldn't break things; I could do some
experimenting sometime and find out.
This output ordering of sections is magic, on the Alpha, at
least. The .lita section must come before .lit8 and .lit4,
otherwise the OSF/1 linker may silently trash the .lit{4,8}
section contents. Also, .text must precede .rdata. These differ
from the order described in some parts of the DEC OSF/1 Assembly
Language Programmer's Guide, but that order doesn't seem to work
with their linker.
I don't know if section ordering on the MIPS is important. */
static const char *const names[] =
{
/* text segment */
".text", ".rdata", ".init", ".fini",
/* data segment */
".data", ".lita", ".lit8", ".lit4", ".sdata", ".got",
/* bss segment */
".sbss", ".bss",
};
#define n_names ((int) (sizeof (names) / sizeof (names[0])))
/* Sections that match names, order to be straightened out later. */
asection *secs[n_names];
int i;
addr = 0;
for (i = 0; i < n_names; i++)
secs[i] = NULL;
for (sec = stdoutput->sections; sec != NULL; sec = sec->next)
{
for (i = 0; i < n_names; i++)
if (!strcmp (sec->name, names[i]))
{
secs[i] = sec;
bfd_section_list_remove (stdoutput, sec);
break;
}
if (i == n_names)
{
bfd_set_section_vma (stdoutput, sec, addr);
addr += bfd_section_size (stdoutput, sec);
}
}
for (i = 0; i < n_names; i++)
if (secs[i])
{
bfd_set_section_vma (stdoutput, secs[i], addr);
addr += bfd_section_size (stdoutput, secs[i]);
}
for (i = n_names - 1; i >= 0; i--)
if (secs[i])
bfd_section_list_prepend (stdoutput, secs[i]);
/* Fill in the register masks. */
{
unsigned long gprmask = 0;
unsigned long fprmask = 0;
unsigned long *cprmask = NULL;
#ifdef TC_MIPS
/* Fill in the MIPS register masks. It's probably not worth
setting up a generic interface for this. */
gprmask = mips_gprmask;
cprmask = mips_cprmask;
#endif
#ifdef TC_ALPHA
alpha_frob_ecoff_data ();
if (! bfd_ecoff_set_gp_value (stdoutput, alpha_gp_value))
as_fatal (_("Can't set GP value"));
gprmask = alpha_gprmask;
fprmask = alpha_fprmask;
#endif
if (! bfd_ecoff_set_regmasks (stdoutput, gprmask, fprmask, cprmask))
as_fatal (_("Can't set register masks"));
}
}
/* Swap out the symbols and debugging information for BFD. */
void
ecoff_frob_file (void)
{
const struct ecoff_debug_swap * const debug_swap
= &ecoff_backend (stdoutput)->debug_swap;
bfd_vma addr ATTRIBUTE_UNUSED;
HDRR *hdr;
char *buf;
char *set;
/* Build the ECOFF debugging information. */
gas_assert (ecoff_data (stdoutput) != 0);
hdr = &ecoff_data (stdoutput)->debug_info.symbolic_header;
ecoff_build_debug (hdr, &buf, debug_swap);
/* Finish up the ecoff_tdata structure. */
set = buf;
#define SET(ptr, count, type, size) \
if (hdr->count == 0) \
ecoff_data (stdoutput)->debug_info.ptr = NULL; \
else \
{ \
ecoff_data (stdoutput)->debug_info.ptr = (type) set; \
set += hdr->count * size; \
}
SET (line, cbLine, unsigned char *, sizeof (unsigned char));
SET (external_dnr, idnMax, void *, debug_swap->external_dnr_size);
SET (external_pdr, ipdMax, void *, debug_swap->external_pdr_size);
SET (external_sym, isymMax, void *, debug_swap->external_sym_size);
SET (external_opt, ioptMax, void *, debug_swap->external_opt_size);
SET (external_aux, iauxMax, union aux_ext *, sizeof (union aux_ext));
SET (ss, issMax, char *, sizeof (char));
SET (ssext, issExtMax, char *, sizeof (char));
SET (external_rfd, crfd, void *, debug_swap->external_rfd_size);
SET (external_fdr, ifdMax, void *, debug_swap->external_fdr_size);
SET (external_ext, iextMax, void *, debug_swap->external_ext_size);
#undef SET
}
/* This is called by the ECOFF code to set the external information
for a symbol. We just pass it on to BFD, which expects the swapped
information to be stored in the native field of the symbol. */
void
obj_ecoff_set_ext (symbolS *sym, EXTR *ext)
{
const struct ecoff_debug_swap * const debug_swap
= &ecoff_backend (stdoutput)->debug_swap;
ecoff_symbol_type *esym;
know (bfd_asymbol_flavour (symbol_get_bfdsym (sym))
== bfd_target_ecoff_flavour);
esym = ecoffsymbol (symbol_get_bfdsym (sym));
esym->local = FALSE;
esym->native = xmalloc (debug_swap->external_ext_size);
(*debug_swap->swap_ext_out) (stdoutput, ext, esym->native);
}
static int
ecoff_sec_sym_ok_for_reloc (asection *sec ATTRIBUTE_UNUSED)
{
return 1;
}
static void
obj_ecoff_frob_symbol (symbolS *sym, int *puntp ATTRIBUTE_UNUSED)
{
ecoff_frob_symbol (sym);
}
static void
ecoff_pop_insert (void)
{
pop_insert (obj_pseudo_table);
}
static int
ecoff_separate_stab_sections (void)
{
return 0;
}
/* These are the pseudo-ops we support in this file. Only those
relating to debugging information are supported here.
The following pseudo-ops from the Kane and Heinrich MIPS book
should be defined here, but are currently unsupported: .bgnb,
.endb, .verstamp, .vreg.
The following pseudo-ops from the Kane and Heinrich MIPS book are
MIPS CPU specific, and should be defined by tc-mips.c: .alias,
.extern, .galive, .gjaldef, .gjrlive, .livereg, .noalias, .option,
.rdata, .sdata, .set.
The following pseudo-ops from the Kane and Heinrich MIPS book are
not MIPS CPU specific, but are also not ECOFF specific. I have
only listed the ones which are not already in read.c. It's not
completely clear where these should be defined, but tc-mips.c is
probably the most reasonable place: .asciiz, .asm0, .endr, .err,
.half, .lab, .repeat, .struct, .weakext. */
const pseudo_typeS obj_pseudo_table[] =
{
/* COFF style debugging information. .ln is not used; .loc is used
instead. */
{ "def", ecoff_directive_def, 0 },
{ "dim", ecoff_directive_dim, 0 },
{ "endef", ecoff_directive_endef, 0 },
{ "file", ecoff_directive_file, 0 },
{ "scl", ecoff_directive_scl, 0 },
{ "size", ecoff_directive_size, 0 },
{ "esize", ecoff_directive_size, 0 },
{ "tag", ecoff_directive_tag, 0 },
{ "type", ecoff_directive_type, 0 },
{ "etype", ecoff_directive_type, 0 },
{ "val", ecoff_directive_val, 0 },
/* ECOFF specific debugging information. */
{ "aent", ecoff_directive_ent, 1 },
{ "begin", ecoff_directive_begin, 0 },
{ "bend", ecoff_directive_bend, 0 },
{ "end", ecoff_directive_end, 0 },
{ "ent", ecoff_directive_ent, 0 },
{ "fmask", ecoff_directive_fmask, 0 },
{ "frame", ecoff_directive_frame, 0 },
{ "loc", ecoff_directive_loc, 0 },
{ "mask", ecoff_directive_mask, 0 },
/* Other ECOFF directives. */
{ "extern", ecoff_directive_extern, 0 },
#ifndef TC_MIPS
/* For TC_MIPS, tc-mips.c adds this. */
{ "weakext", ecoff_directive_weakext, 0 },
#endif
/* These are used on Irix. I don't know how to implement them. */
{ "bgnb", s_ignore, 0 },
{ "endb", s_ignore, 0 },
{ "verstamp", s_ignore, 0 },
/* Sentinel. */
{ NULL, s_ignore, 0 }
};
const struct format_ops ecoff_format_ops =
{
bfd_target_ecoff_flavour,
0, /* dfl_leading_underscore. */
/* FIXME: A comment why emit_section_symbols is different here (1) from
the single-format definition (0) would be in order. */
1, /* emit_section_symbols. */
0, /* begin. */
ecoff_new_file,
obj_ecoff_frob_symbol,
ecoff_frob_file,
0, /* frob_file_before_adjust. */
ecoff_frob_file_before_fix,
0, /* frob_file_after_relocs. */
0, /* s_get_size. */
0, /* s_set_size. */
0, /* s_get_align. */
0, /* s_set_align. */
0, /* s_get_other. */
0, /* s_set_other. */
0, /* s_get_desc. */
0, /* s_set_desc. */
0, /* s_get_type. */
0, /* s_set_type. */
0, /* copy_symbol_attributes. */
ecoff_generate_asm_lineno,
ecoff_stab,
ecoff_separate_stab_sections,
0, /* init_stab_section. */
ecoff_sec_sym_ok_for_reloc,
ecoff_pop_insert,
ecoff_set_ext,
ecoff_read_begin_hook,
ecoff_symbol_new_hook,
ecoff_symbol_clone_hook,
0 /* adjust_symtab. */
};