/* AVR-specific support for 32-bit ELF
- Copyright (C) 1999-2015 Free Software Foundation, Inc.
+ Copyright (C) 1999-2017 Free Software Foundation, Inc.
Contributed by Denis Chertykov <denisc@overta.ru>
This file is part of BFD, the Binary File Descriptor library.
/* Assorted information used by elf32_avr_size_stubs. */
unsigned int bfd_count;
- int top_index;
+ unsigned int top_index;
asection ** input_list;
Elf_Internal_Sym ** all_local_syms;
FALSE, /* partial_inplace */
0xffffff, /* src_mask */
0xffffff, /* dst_mask */
- FALSE) /* pcrel_offset */
+ FALSE), /* pcrel_offset */
+
+ /* A 32 bit PC relative relocation. */
+ HOWTO (R_AVR_32_PCREL, /* type */
+ 0, /* rightshift */
+ 2, /* size (0 = byte, 1 = short, 2 = long) */
+ 32, /* bitsize */
+ TRUE, /* pc_relative */
+ 0, /* bitpos */
+ complain_overflow_bitfield, /* complain_on_overflow */
+ bfd_elf_generic_reloc, /* special_function */
+ "R_AVR_32_PCREL", /* name */
+ FALSE, /* partial_inplace */
+ 0xffffffff, /* src_mask */
+ 0xffffffff, /* dst_mask */
+ TRUE), /* pcrel_offset */
};
/* Map BFD reloc types to AVR ELF reloc types. */
{ BFD_RELOC_AVR_DIFF32, R_AVR_DIFF32 },
{ BFD_RELOC_AVR_LDS_STS_16, R_AVR_LDS_STS_16},
{ BFD_RELOC_AVR_PORT6, R_AVR_PORT6},
- { BFD_RELOC_AVR_PORT5, R_AVR_PORT5}
+ { BFD_RELOC_AVR_PORT5, R_AVR_PORT5},
+ { BFD_RELOC_32_PCREL, R_AVR_32_PCREL}
};
/* Meant to be filled one day with the wrap around address for the
instruction. This option could be switched off by a linker switch. */
static int avr_replace_call_ret_sequences = 1;
\f
+
+/* Per-section relaxation related information for avr. */
+
+struct avr_relax_info
+{
+ /* Track the avr property records that apply to this section. */
+
+ struct
+ {
+ /* Number of records in the list. */
+ unsigned count;
+
+ /* How many records worth of space have we allocated. */
+ unsigned allocated;
+
+ /* The records, only COUNT records are initialised. */
+ struct avr_property_record *items;
+ } records;
+};
+
+/* Per section data, specialised for avr. */
+
+struct elf_avr_section_data
+{
+ /* The standard data must appear first. */
+ struct bfd_elf_section_data elf;
+
+ /* Relaxation related information. */
+ struct avr_relax_info relax_info;
+};
+
+/* Possibly initialise avr specific data for new section SEC from ABFD. */
+
+static bfd_boolean
+elf_avr_new_section_hook (bfd *abfd, asection *sec)
+{
+ if (!sec->used_by_bfd)
+ {
+ struct elf_avr_section_data *sdata;
+ bfd_size_type amt = sizeof (*sdata);
+
+ sdata = bfd_zalloc (abfd, amt);
+ if (sdata == NULL)
+ return FALSE;
+ sec->used_by_bfd = sdata;
+ }
+
+ return _bfd_elf_new_section_hook (abfd, sec);
+}
+
+/* Return a pointer to the relaxation information for SEC. */
+
+static struct avr_relax_info *
+get_avr_relax_info (asection *sec)
+{
+ struct elf_avr_section_data *section_data;
+
+ /* No info available if no section or if it is an output section. */
+ if (!sec || sec == sec->output_section)
+ return NULL;
+
+ section_data = (struct elf_avr_section_data *) elf_section_data (sec);
+ return §ion_data->relax_info;
+}
+
+/* Initialise the per section relaxation information for SEC. */
+
+static void
+init_avr_relax_info (asection *sec)
+{
+ struct avr_relax_info *relax_info = get_avr_relax_info (sec);
+
+ relax_info->records.count = 0;
+ relax_info->records.allocated = 0;
+ relax_info->records.items = NULL;
+}
+
/* Initialize an entry in the stub hash table. */
static struct bfd_hash_entry *
r_type = ELF32_R_TYPE (dst->r_info);
if (r_type >= (unsigned int) R_AVR_max)
{
+ /* xgettext:c-format */
_bfd_error_handler (_("%B: invalid AVR reloc number: %d"), abfd, r_type);
r_type = 0;
}
RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section,
rel, 1, relend, howto, 0, contents);
- if (info->relocatable)
+ if (bfd_link_relocatable (info))
continue;
r = avr_final_link_relocate (howto, input_bfd, input_section,
switch (r)
{
case bfd_reloc_overflow:
- r = info->callbacks->reloc_overflow
- (info, (h ? &h->root : NULL),
- name, howto->name, (bfd_vma) 0,
- input_bfd, input_section, rel->r_offset);
+ (*info->callbacks->reloc_overflow)
+ (info, (h ? &h->root : NULL), name, howto->name,
+ (bfd_vma) 0, input_bfd, input_section, rel->r_offset);
break;
case bfd_reloc_undefined:
- r = info->callbacks->undefined_symbol
+ (*info->callbacks->undefined_symbol)
(info, name, input_bfd, input_section, rel->r_offset, TRUE);
break;
}
if (msg)
- r = info->callbacks->warning
- (info, msg, name, input_bfd, input_section, rel->r_offset);
-
- if (! r)
- return FALSE;
+ (*info->callbacks->warning) (info, msg, name, input_bfd,
+ input_section, rel->r_offset);
}
}
reloc_contents = isec_contents + irel->r_offset;
/* Read value written in object file. */
- bfd_vma x = 0;
+ bfd_signed_vma x = 0;
switch (ELF32_R_TYPE (irel->r_info))
{
case R_AVR_DIFF8:
{
- x = *reloc_contents;
+ x = bfd_get_signed_8 (abfd, reloc_contents);
break;
}
case R_AVR_DIFF16:
{
- x = bfd_get_16 (abfd, reloc_contents);
+ x = bfd_get_signed_16 (abfd, reloc_contents);
break;
}
case R_AVR_DIFF32:
{
- x = bfd_get_32 (abfd, reloc_contents);
+ x = bfd_get_signed_32 (abfd, reloc_contents);
break;
}
default:
symval (<start_of_section>) + reloc addend. Compute the start and end
addresses and check if the shrinked insn falls between sym1 and sym2. */
- bfd_vma end_address = symval + irel->r_addend;
- bfd_vma start_address = end_address - x;
+ bfd_vma sym2_address = symval + irel->r_addend;
+ bfd_vma sym1_address = sym2_address - x;
+
+ /* Don't assume sym2 is bigger than sym1 - the difference
+ could be negative. Compute start and end addresses, and
+ use those to see if they span shrinked_insn_address. */
+
+ bfd_vma start_address = sym1_address < sym2_address
+ ? sym1_address : sym2_address;
+ bfd_vma end_address = sym1_address > sym2_address
+ ? sym1_address : sym2_address;
- /* Reduce the diff value by count bytes and write it back into section
- contents. */
if (shrinked_insn_address >= start_address
&& shrinked_insn_address <= end_address)
{
+ /* Reduce the diff value by count bytes and write it back into section
+ contents. */
+ bfd_signed_vma new_diff = x < 0 ? x + count : x - count;
+
switch (ELF32_R_TYPE (irel->r_info))
{
case R_AVR_DIFF8:
{
- *reloc_contents = (x - count);
+ bfd_put_signed_8 (abfd, new_diff, reloc_contents);
break;
}
case R_AVR_DIFF16:
{
- bfd_put_16 (abfd, (x - count) & 0xFFFF, reloc_contents);
+ bfd_put_signed_16 (abfd, new_diff & 0xFFFF, reloc_contents);
break;
}
case R_AVR_DIFF32:
{
- bfd_put_32 (abfd, (x - count) & 0xFFFFFFFF, reloc_contents);
+ bfd_put_signed_32 (abfd, new_diff & 0xFFFFFFFF, reloc_contents);
break;
}
default:
}
}
+static void
+elf32_avr_adjust_reloc_if_spans_insn (bfd *abfd,
+ asection *isec,
+ Elf_Internal_Rela *irel, bfd_vma symval,
+ bfd_vma shrinked_insn_address,
+ bfd_vma shrink_boundary,
+ int count)
+{
+
+ if (elf32_avr_is_diff_reloc (irel))
+ {
+ elf32_avr_adjust_diff_reloc_value (abfd, isec, irel,
+ symval,
+ shrinked_insn_address,
+ count);
+ }
+ else
+ {
+ bfd_vma reloc_value = symval + irel->r_addend;
+ bfd_boolean addend_within_shrink_boundary =
+ (reloc_value <= shrink_boundary);
+
+ bfd_boolean reloc_spans_insn =
+ (symval <= shrinked_insn_address
+ && reloc_value > shrinked_insn_address
+ && addend_within_shrink_boundary);
+
+ if (! reloc_spans_insn)
+ return;
+
+ irel->r_addend -= count;
+
+ if (debug_relax)
+ printf ("Relocation's addend needed to be fixed \n");
+ }
+}
+
/* Delete some bytes from a section while changing the size of an instruction.
The parameter "addr" denotes the section-relative offset pointing just
behind the shrinked instruction. "addr+count" point at the first
- byte just behind the original unshrinked instruction. */
+ byte just behind the original unshrinked instruction. If delete_shrinks_insn
+ is FALSE, we are deleting redundant padding bytes from relax_info prop
+ record handling. In that case, addr is section-relative offset of start
+ of padding, and count is the number of padding bytes to delete. */
static bfd_boolean
elf32_avr_relax_delete_bytes (bfd *abfd,
asection *sec,
bfd_vma addr,
- int count)
+ int count,
+ bfd_boolean delete_shrinks_insn)
{
Elf_Internal_Shdr *symtab_hdr;
unsigned int sec_shndx;
Elf_Internal_Rela *irel, *irelend;
Elf_Internal_Sym *isym;
Elf_Internal_Sym *isymbuf = NULL;
- bfd_vma toaddr;
+ bfd_vma toaddr, reloc_toaddr;
struct elf_link_hash_entry **sym_hashes;
struct elf_link_hash_entry **end_hashes;
unsigned int symcount;
+ struct avr_relax_info *relax_info;
+ struct avr_property_record *prop_record = NULL;
+ bfd_boolean did_shrink = FALSE;
symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
sec_shndx = _bfd_elf_section_from_bfd_section (abfd, sec);
contents = elf_section_data (sec)->this_hdr.contents;
+ relax_info = get_avr_relax_info (sec);
toaddr = sec->size;
+ if (relax_info->records.count > 0)
+ {
+ /* There should be no property record within the range of deleted
+ bytes, however, there might be a property record for ADDR, this is
+ how we handle alignment directives.
+ Find the next (if any) property record after the deleted bytes. */
+ unsigned int i;
+
+ for (i = 0; i < relax_info->records.count; ++i)
+ {
+ bfd_vma offset = relax_info->records.items [i].offset;
+
+ BFD_ASSERT (offset <= addr || offset >= (addr + count));
+ if (offset >= (addr + count))
+ {
+ prop_record = &relax_info->records.items [i];
+ toaddr = offset;
+ break;
+ }
+ }
+ }
+
+ /* We need to look at all relocs with offsets less than toaddr. prop
+ records handling adjusts toaddr downwards to avoid moving syms at the
+ address of the property record, but all relocs with offsets between addr
+ and the current value of toaddr need to have their offsets adjusted.
+ Assume addr = 0, toaddr = 4 and count = 2. After prop records handling,
+ toaddr becomes 2, but relocs with offsets 2 and 3 still need to be
+ adjusted (to 0 and 1 respectively), as the first 2 bytes are now gone.
+ So record the current value of toaddr here, and use it when adjusting
+ reloc offsets. */
+ reloc_toaddr = toaddr;
+
irel = elf_section_data (sec)->relocs;
irelend = irel + sec->reloc_count;
/* Actually delete the bytes. */
if (toaddr - addr - count > 0)
- memmove (contents + addr, contents + addr + count,
- (size_t) (toaddr - addr - count));
- sec->size -= count;
+ {
+ memmove (contents + addr, contents + addr + count,
+ (size_t) (toaddr - addr - count));
+ did_shrink = TRUE;
+ }
+ if (prop_record == NULL)
+ {
+ sec->size -= count;
+ did_shrink = TRUE;
+ }
+ else
+ {
+ /* Use the property record to fill in the bytes we've opened up. */
+ int fill = 0;
+ switch (prop_record->type)
+ {
+ case RECORD_ORG_AND_FILL:
+ fill = prop_record->data.org.fill;
+ /* Fall through. */
+ case RECORD_ORG:
+ break;
+ case RECORD_ALIGN_AND_FILL:
+ fill = prop_record->data.align.fill;
+ /* Fall through. */
+ case RECORD_ALIGN:
+ prop_record->data.align.preceding_deleted += count;
+ break;
+ };
+ /* If toaddr == (addr + count), then we didn't delete anything, yet
+ we fill count bytes backwards from toaddr. This is still ok - we
+ end up overwriting the bytes we would have deleted. We just need
+ to remember we didn't delete anything i.e. don't set did_shrink,
+ so that we don't corrupt reloc offsets or symbol values.*/
+ memset (contents + toaddr - count, fill, count);
+
+ /* Adjust the TOADDR to avoid moving symbols located at the address
+ of the property record, which has not moved. */
+ toaddr -= count;
+ }
+
+ if (!did_shrink)
+ return TRUE;
/* Adjust all the reloc addresses. */
for (irel = elf_section_data (sec)->relocs; irel < irelend; irel++)
/* Get the new reloc address. */
if ((irel->r_offset > addr
- && irel->r_offset < toaddr))
+ && irel->r_offset < reloc_toaddr))
{
if (debug_relax)
printf ("Relocation at address 0x%x needs to be moved.\n"
continue;
shrinked_insn_address = (sec->output_section->vma
- + sec->output_offset + addr - count);
+ + sec->output_offset + addr);
+ if (delete_shrinks_insn)
+ shrinked_insn_address -= count;
irel = elf_section_data (isec)->relocs;
/* PR 12161: Read in the relocs for this section if necessary. */
a symbol or section associated with it. */
if (sym_sec == sec)
{
+ /* If there is an alignment boundary, we only need to
+ adjust addends that end up below the boundary. */
+ bfd_vma shrink_boundary = (reloc_toaddr
+ + sec->output_section->vma
+ + sec->output_offset);
+
symval += sym_sec->output_section->vma
+ sym_sec->output_offset;
(unsigned int) (symval + irel->r_addend),
(unsigned int) shrinked_insn_address);
- if (symval <= shrinked_insn_address
- && (symval + irel->r_addend) > shrinked_insn_address)
- {
- if (elf32_avr_is_diff_reloc (irel))
- {
- elf32_avr_adjust_diff_reloc_value (abfd, isec, irel,
+ elf32_avr_adjust_reloc_if_spans_insn (abfd, isec, irel,
symval,
shrinked_insn_address,
- count);
- }
-
- irel->r_addend -= count;
-
- if (debug_relax)
- printf ("Relocation's addend needed to be fixed \n");
- }
+ shrink_boundary,
+ count);
}
/* else...Reference symbol is absolute. No adjustment needed. */
}
return offset;
}
+/* Iterate over the property records in R_LIST, and copy each record into
+ the list of records within the relaxation information for the section to
+ which the record applies. */
+
+static void
+avr_elf32_assign_records_to_sections (struct avr_property_record_list *r_list)
+{
+ unsigned int i;
+
+ for (i = 0; i < r_list->record_count; ++i)
+ {
+ struct avr_relax_info *relax_info;
+
+ relax_info = get_avr_relax_info (r_list->records [i].section);
+ BFD_ASSERT (relax_info != NULL);
+
+ if (relax_info->records.count
+ == relax_info->records.allocated)
+ {
+ /* Allocate more space. */
+ bfd_size_type size;
+
+ relax_info->records.allocated += 10;
+ size = (sizeof (struct avr_property_record)
+ * relax_info->records.allocated);
+ relax_info->records.items
+ = bfd_realloc (relax_info->records.items, size);
+ }
+
+ memcpy (&relax_info->records.items [relax_info->records.count],
+ &r_list->records [i],
+ sizeof (struct avr_property_record));
+ relax_info->records.count++;
+ }
+}
+
+/* Compare two STRUCT AVR_PROPERTY_RECORD in AP and BP, used as the
+ ordering callback from QSORT. */
+
+static int
+avr_property_record_compare (const void *ap, const void *bp)
+{
+ const struct avr_property_record *a
+ = (struct avr_property_record *) ap;
+ const struct avr_property_record *b
+ = (struct avr_property_record *) bp;
+
+ if (a->offset != b->offset)
+ return (a->offset - b->offset);
+
+ if (a->section != b->section)
+ return (bfd_get_section_vma (a->section->owner, a->section)
+ - bfd_get_section_vma (b->section->owner, b->section));
+
+ return (a->type - b->type);
+}
+
+/* Load all of the avr property sections from all of the bfd objects
+ referenced from LINK_INFO. All of the records within each property
+ section are assigned to the STRUCT AVR_RELAX_INFO within the section
+ specific data of the appropriate section. */
+
+static void
+avr_load_all_property_sections (struct bfd_link_info *link_info)
+{
+ bfd *abfd;
+ asection *sec;
+
+ /* Initialize the per-section relaxation info. */
+ for (abfd = link_info->input_bfds; abfd != NULL; abfd = abfd->link.next)
+ for (sec = abfd->sections; sec != NULL; sec = sec->next)
+ {
+ init_avr_relax_info (sec);
+ }
+
+ /* Load the descriptor tables from .avr.prop sections. */
+ for (abfd = link_info->input_bfds; abfd != NULL; abfd = abfd->link.next)
+ {
+ struct avr_property_record_list *r_list;
+
+ r_list = avr_elf32_load_property_records (abfd);
+ if (r_list != NULL)
+ avr_elf32_assign_records_to_sections (r_list);
+
+ free (r_list);
+ }
+
+ /* Now, for every section, ensure that the descriptor list in the
+ relaxation data is sorted by ascending offset within the section. */
+ for (abfd = link_info->input_bfds; abfd != NULL; abfd = abfd->link.next)
+ for (sec = abfd->sections; sec != NULL; sec = sec->next)
+ {
+ struct avr_relax_info *relax_info = get_avr_relax_info (sec);
+ if (relax_info && relax_info->records.count > 0)
+ {
+ unsigned int i;
+
+ qsort (relax_info->records.items,
+ relax_info->records.count,
+ sizeof (struct avr_property_record),
+ avr_property_record_compare);
+
+ /* For debug purposes, list all the descriptors. */
+ for (i = 0; i < relax_info->records.count; ++i)
+ {
+ switch (relax_info->records.items [i].type)
+ {
+ case RECORD_ORG:
+ break;
+ case RECORD_ORG_AND_FILL:
+ break;
+ case RECORD_ALIGN:
+ break;
+ case RECORD_ALIGN_AND_FILL:
+ break;
+ };
+ }
+ }
+ }
+}
+
/* This function handles relaxing for the avr.
Many important relaxing opportunities within functions are already
realized by the compiler itself.
bfd_byte *contents = NULL;
Elf_Internal_Sym *isymbuf = NULL;
struct elf32_avr_link_hash_table *htab;
+ static bfd_boolean relaxation_initialised = FALSE;
+
+ if (!relaxation_initialised)
+ {
+ relaxation_initialised = TRUE;
+
+ /* Load entries from the .avr.prop sections. */
+ avr_load_all_property_sections (link_info);
+ }
/* If 'shrinkable' is FALSE, do not shrink by deleting bytes while
relaxing. Such shrinking can cause issues for the sections such
|| !strcmp (sec->name,".jumptables"))
shrinkable = FALSE;
- if (link_info->relocatable)
+ if (bfd_link_relocatable (link_info))
(*link_info->callbacks->einfo)
(_("%P%F: --relax and -r may not be used together\n"));
/* We don't have to do anything for a relocatable link, if
this section does not have relocs, or if this is not a
code section. */
- if (link_info->relocatable
+ if (bfd_link_relocatable (link_info)
|| (sec->flags & SEC_RELOC) == 0
|| sec->reloc_count == 0
|| (sec->flags & SEC_CODE) == 0)
{
/* Delete two bytes of data. */
if (!elf32_avr_relax_delete_bytes (abfd, sec,
- irel->r_offset + 2, 2))
+ irel->r_offset + 2, 2,
+ TRUE))
goto error_return;
/* That will change things, so, we should relax again.
}
}
}
+ /* Fall through. */
default:
{
/* Delete two bytes of data. */
if (!elf32_avr_relax_delete_bytes (abfd, sec,
- irel->r_offset + insn_size, 2))
+ irel->r_offset + insn_size, 2,
+ TRUE))
goto error_return;
/* That will change things, so, we should relax
}
}
+ if (!*again)
+ {
+ /* Look through all the property records in this section to see if
+ there's any alignment records that can be moved. */
+ struct avr_relax_info *relax_info;
+
+ relax_info = get_avr_relax_info (sec);
+ if (relax_info->records.count > 0)
+ {
+ unsigned int i;
+
+ for (i = 0; i < relax_info->records.count; ++i)
+ {
+ switch (relax_info->records.items [i].type)
+ {
+ case RECORD_ORG:
+ case RECORD_ORG_AND_FILL:
+ break;
+ case RECORD_ALIGN:
+ case RECORD_ALIGN_AND_FILL:
+ {
+ struct avr_property_record *record;
+ unsigned long bytes_to_align;
+ int count = 0;
+
+ /* Look for alignment directives that have had enough
+ bytes deleted before them, such that the directive
+ can be moved backwards and still maintain the
+ required alignment. */
+ record = &relax_info->records.items [i];
+ bytes_to_align
+ = (unsigned long) (1 << record->data.align.bytes);
+ while (record->data.align.preceding_deleted >=
+ bytes_to_align)
+ {
+ record->data.align.preceding_deleted
+ -= bytes_to_align;
+ count += bytes_to_align;
+ }
+
+ if (count > 0)
+ {
+ bfd_vma addr = record->offset;
+
+ /* We can delete COUNT bytes and this alignment
+ directive will still be correctly aligned.
+ First move the alignment directive, then delete
+ the bytes. */
+ record->offset -= count;
+ elf32_avr_relax_delete_bytes (abfd, sec,
+ addr - count,
+ count, FALSE);
+ *again = TRUE;
+ }
+ }
+ break;
+ }
+ }
+ }
+ }
+
if (contents != NULL
&& elf_section_data (sec)->this_hdr.contents != contents)
{
if (hsh == NULL)
{
- (*_bfd_error_handler) (_("%B: cannot create stub entry %s"),
- NULL, stub_name);
+ /* xgettext:c-format */
+ _bfd_error_handler (_("%B: cannot create stub entry %s"),
+ NULL, stub_name);
return NULL;
}
{
bfd *input_bfd;
unsigned int bfd_count;
- int top_id, top_index;
+ unsigned int top_id, top_index;
asection *section;
asection **input_list, **list;
bfd_size_type amt;
}
else if (hh->root.type == bfd_link_hash_undefweak)
{
- if (! info->shared)
+ if (! bfd_link_pic (info))
continue;
}
else if (hh->root.type == bfd_link_hash_undefined)
}
free (contents);
- free (internal_relocs);
+ if (elf_section_data (sec)->relocs != internal_relocs)
+ free (internal_relocs);
return r_list;
load_failed:
- free (internal_relocs);
+ if (elf_section_data (sec)->relocs != internal_relocs)
+ free (internal_relocs);
free (contents);
free (r_list);
return NULL;
#define bfd_elf32_bfd_relax_section elf32_avr_relax_section
#define bfd_elf32_bfd_get_relocated_section_contents \
elf32_avr_get_relocated_section_contents
+#define bfd_elf32_new_section_hook elf_avr_new_section_hook
#include "elf32-target.h"