* elflink.c (_bfd_elf_merge_symbol): Use local var holding value
[binutils-gdb.git] / bfd / elf32-avr.c
index 1bc40c4403a9ea1dfb7376bfcbd6d8a6bca8a809..a2d440129a455dc2b2cac503e9a2c0110c44cdd4 100644 (file)
@@ -1,6 +1,7 @@
 /* AVR-specific support for 32-bit ELF
    Copyright 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
-   2010  Free Software Foundation, Inc.
+   2010, 2011, 2012
+   Free Software Foundation, Inc.
    Contributed by Denis Chertykov <denisc@overta.ru>
 
    This file is part of BFD, the Binary File Descriptor library.
@@ -516,6 +517,48 @@ static reloc_howto_type elf_avr_howto_table[] =
         0x000000ff,            /* src_mask */
         0x000000ff,            /* dst_mask */
         FALSE),                /* pcrel_offset */
+  /* lo8-part to use in  .byte lo8(sym).  */
+  HOWTO (R_AVR_8_LO8,          /* type */
+        0,                     /* rightshift */
+        0,                     /* size (0 = byte, 1 = short, 2 = long) */
+        8,                     /* bitsize */
+        FALSE,                 /* pc_relative */
+        0,                     /* bitpos */
+        complain_overflow_dont,/* complain_on_overflow */
+        bfd_elf_generic_reloc, /* special_function */
+        "R_AVR_8_LO8",         /* name */
+        FALSE,                 /* partial_inplace */
+        0xffffff,              /* src_mask */
+        0xffffff,              /* dst_mask */
+        FALSE),                /* pcrel_offset */
+  /* hi8-part to use in  .byte hi8(sym).  */
+  HOWTO (R_AVR_8_HI8,          /* type */
+        8,                     /* rightshift */
+        0,                     /* size (0 = byte, 1 = short, 2 = long) */
+        8,                     /* bitsize */
+        FALSE,                 /* pc_relative */
+        0,                     /* bitpos */
+        complain_overflow_dont,/* complain_on_overflow */
+        bfd_elf_generic_reloc, /* special_function */
+        "R_AVR_8_HI8",         /* name */
+        FALSE,                 /* partial_inplace */
+        0xffffff,              /* src_mask */
+        0xffffff,              /* dst_mask */
+        FALSE),                /* pcrel_offset */
+  /* hlo8-part to use in  .byte hlo8(sym).  */
+  HOWTO (R_AVR_8_HLO8,         /* type */
+        16,                    /* rightshift */
+        0,                     /* size (0 = byte, 1 = short, 2 = long) */
+        8,                     /* bitsize */
+        FALSE,                 /* pc_relative */
+        0,                     /* bitpos */
+        complain_overflow_dont,/* complain_on_overflow */
+        bfd_elf_generic_reloc, /* special_function */
+        "R_AVR_8_HLO8",        /* name */
+        FALSE,                 /* partial_inplace */
+        0xffffff,              /* src_mask */
+        0xffffff,              /* dst_mask */
+        FALSE),                /* pcrel_offset */
 };
 
 /* Map BFD reloc types to AVR ELF reloc types.  */
@@ -554,7 +597,10 @@ static const struct avr_reloc_map avr_reloc_map[] =
   { BFD_RELOC_AVR_LDI,              R_AVR_LDI  },
   { BFD_RELOC_AVR_6,                R_AVR_6    },
   { BFD_RELOC_AVR_6_ADIW,           R_AVR_6_ADIW },
-  { BFD_RELOC_8,                    R_AVR_8 }
+  { BFD_RELOC_8,                    R_AVR_8 },
+  { BFD_RELOC_AVR_8_LO,             R_AVR_8_LO8 },
+  { BFD_RELOC_AVR_8_HI,             R_AVR_8_HI8 },
+  { BFD_RELOC_AVR_8_HLO,            R_AVR_8_HLO8 }
 };
 
 /* Meant to be filled one day with the wrap around address for the
@@ -626,7 +672,7 @@ elf32_avr_link_hash_table_create (bfd *abfd)
   struct elf32_avr_link_hash_table *htab;
   bfd_size_type amt = sizeof (*htab);
 
-  htab = bfd_malloc (amt);
+  htab = bfd_zmalloc (amt);
   if (htab == NULL)
     return NULL;
 
@@ -644,15 +690,6 @@ elf32_avr_link_hash_table_create (bfd *abfd)
                             sizeof (struct elf32_avr_stub_hash_entry)))
     return NULL;
 
-  htab->stub_bfd = NULL;
-  htab->stub_sec = NULL;
-
-  /* Initialize the address mapping table.  */
-  htab->amt_stub_offsets = NULL;
-  htab->amt_destination_addr = NULL;
-  htab->amt_entry_cnt = 0;
-  htab->amt_max_entry_cnt = 0;
-
   return &htab->etab.root;
 }
 
@@ -671,7 +708,7 @@ elf32_avr_link_hash_table_free (struct bfd_link_hash_table *btab)
     free (htab->amt_destination_addr);
 
   bfd_hash_table_free (&htab->bstab);
-  _bfd_generic_link_hash_table_free (btab);
+  _bfd_elf_link_hash_table_free (btab);
 }
 
 /* Calculates the effective distance of a pc relative jump/call.  */
@@ -1189,9 +1226,9 @@ elf32_avr_relocate_section (bfd *output_bfd ATTRIBUTE_UNUSED,
          name = h->root.root.string;
        }
 
-      if (sec != NULL && elf_discarded_section (sec))
+      if (sec != NULL && discarded_section (sec))
        RELOC_AGAINST_DISCARDED_SECTION (info, input_bfd, input_section,
-                                        rel, relend, howto, contents);
+                                        rel, 1, relend, howto, 0, contents);
 
       if (info->relocatable)
        continue;
@@ -1503,11 +1540,18 @@ elf32_avr_relax_delete_bytes (bfd *abfd,
        bfd_vma symval;
        bfd_vma shrinked_insn_address;
 
+       if (isec->reloc_count == 0)
+        continue;
+
        shrinked_insn_address = (sec->output_section->vma
                                 + sec->output_offset + addr - count);
 
-       irelend = elf_section_data (isec)->relocs + isec->reloc_count;
-       for (irel = elf_section_data (isec)->relocs;
+       irel = elf_section_data (isec)->relocs;
+       /* PR 12161: Read in the relocs for this section if necessary.  */
+       if (irel == NULL)
+         irel = _bfd_elf_link_read_relocs (abfd, isec, NULL, NULL, TRUE);
+
+       for (irelend = irel + isec->reloc_count;
             irel < irelend;
             irel++)
          {
@@ -1649,6 +1693,16 @@ elf32_avr_relax_section (bfd *abfd,
   Elf_Internal_Sym *isymbuf = NULL;
   struct elf32_avr_link_hash_table *htab;
 
+  /* If 'shrinkable' is FALSE, do not shrink by deleting bytes while
+     relaxing. Such shrinking can cause issues for the sections such
+     as .vectors and .jumptables. Instead the unused bytes should be
+     filled with nop instructions. */
+  bfd_boolean shrinkable = TRUE;
+
+  if (!strcmp (sec->name,".vectors")
+      || !strcmp (sec->name,".jumptables"))
+    shrinkable = FALSE;
+
   if (link_info->relocatable)
     (*link_info->callbacks->einfo)
       (_("%P%F: --relax and -r may not be used together\n"));
@@ -1805,10 +1859,16 @@ elf32_avr_relax_section (bfd *abfd,
             /* Compute the distance from this insn to the branch target.  */
             gap = value - dot;
 
-            /* If the distance is within -4094..+4098 inclusive, then we can
-               relax this jump/call.  +4098 because the call/jump target
-               will be closer after the relaxation.  */
-            if ((int) gap >= -4094 && (int) gap <= 4098)
+            /* Check if the gap falls in the range that can be accommodated
+               in 13bits signed (It is 12bits when encoded, as we deal with
+               word addressing). */
+            if (!shrinkable && ((int) gap >= -4096 && (int) gap <= 4095))
+              distance_short_enough = 1;
+            /* If shrinkable, then we can check for a range of distance which
+               is two bytes farther on both the directions because the call
+               or jump target will be closer by two bytes after the
+               relaxation. */
+            else if (shrinkable && ((int) gap >= -4094 && (int) gap <= 4097))
               distance_short_enough = 1;
 
             /* Here we handle the wrap-around case.  E.g. for a 16k device
@@ -1882,11 +1942,9 @@ elf32_avr_relax_section (bfd *abfd,
                 irel->r_info = ELF32_R_INFO (ELF32_R_SYM (irel->r_info),
                                              R_AVR_13_PCREL);
 
-                /* Check for the vector section. There we don't want to
-                   modify the ordering!  */
-
-                if (!strcmp (sec->name,".vectors")
-                    || !strcmp (sec->name,".jumptables"))
+                /* We should not modify the ordering if 'shrinkable' is
+                   FALSE. */
+                if (!shrinkable)
                   {
                     /* Let's insert a nop.  */
                     bfd_put_8 (abfd, 0x00, contents + irel->r_offset + 2);
@@ -2008,10 +2066,10 @@ elf32_avr_relax_section (bfd *abfd,
                 if ((0x95 == next_insn_msb) && (0x08 == next_insn_lsb))
                   {
                     /* The next insn is a ret. We possibly could delete
-                       this ret. First we need to check for preceeding
+                       this ret. First we need to check for preceding
                        sbis/sbic/sbrs or cpse "skip" instructions.  */
 
-                    int there_is_preceeding_non_skip_insn = 1;
+                    int there_is_preceding_non_skip_insn = 1;
                     bfd_vma address_of_ret;
 
                     address_of_ret = dot + insn_size;
@@ -2023,51 +2081,52 @@ elf32_avr_relax_section (bfd *abfd,
                       printf ("found jmp / ret sequence at address 0x%x\n",
                               (int) dot);
 
-                    /* We have to make sure that there is a preceeding insn.  */
+                    /* We have to make sure that there is a preceding insn.  */
                     if (irel->r_offset >= 2)
                       {
-                        unsigned char preceeding_msb;
-                        unsigned char preceeding_lsb;
-                        preceeding_msb =
+                        unsigned char preceding_msb;
+                        unsigned char preceding_lsb;
+
+                        preceding_msb =
                          bfd_get_8 (abfd, contents + irel->r_offset - 1);
-                        preceeding_lsb =
+                        preceding_lsb =
                          bfd_get_8 (abfd, contents + irel->r_offset - 2);
 
                         /* sbic.  */
-                        if (0x99 == preceeding_msb)
-                          there_is_preceeding_non_skip_insn = 0;
+                        if (0x99 == preceding_msb)
+                          there_is_preceding_non_skip_insn = 0;
 
                         /* sbis.  */
-                        if (0x9b == preceeding_msb)
-                          there_is_preceeding_non_skip_insn = 0;
+                        if (0x9b == preceding_msb)
+                          there_is_preceding_non_skip_insn = 0;
 
                         /* sbrc */
-                        if ((0xfc == (preceeding_msb & 0xfe)
-                            && (0x00 == (preceeding_lsb & 0x08))))
-                          there_is_preceeding_non_skip_insn = 0;
+                        if ((0xfc == (preceding_msb & 0xfe)
+                            && (0x00 == (preceding_lsb & 0x08))))
+                          there_is_preceding_non_skip_insn = 0;
 
                         /* sbrs */
-                        if ((0xfe == (preceeding_msb & 0xfe)
-                            && (0x00 == (preceeding_lsb & 0x08))))
-                          there_is_preceeding_non_skip_insn = 0;
+                        if ((0xfe == (preceding_msb & 0xfe)
+                            && (0x00 == (preceding_lsb & 0x08))))
+                          there_is_preceding_non_skip_insn = 0;
 
                         /* cpse */
-                        if (0x10 == (preceeding_msb & 0xfc))
-                          there_is_preceeding_non_skip_insn = 0;
+                        if (0x10 == (preceding_msb & 0xfc))
+                          there_is_preceding_non_skip_insn = 0;
 
-                        if (there_is_preceeding_non_skip_insn == 0)
+                        if (there_is_preceding_non_skip_insn == 0)
                           if (debug_relax)
-                            printf ("preceeding skip insn prevents deletion of"
-                                    " ret insn at addr 0x%x in section %s\n",
+                            printf ("preceding skip insn prevents deletion of"
+                                    " ret insn at Addy 0x%x in section %s\n",
                                     (int) dot + 2, sec->name);
                       }
                     else
                       {
                         /* There is no previous instruction.  */
-                        there_is_preceeding_non_skip_insn = 0;
+                        there_is_preceding_non_skip_insn = 0;
                       }
 
-                    if (there_is_preceeding_non_skip_insn)
+                    if (there_is_preceding_non_skip_insn)
                       {
                         /* We now only have to make sure that there is no
                            local label defined at the address of the ret