* config/tc-mn10300.c (mn10300_force_relocation): Force a reloc to be generated for alignment fixups.

* config/tc-mn10300.h (TC_FORCE_RELOCATION): Call mn10300_force_relocation.
* elf-m10300.c (mn10300_elf_final_link_relocate): Prevent the accidental termination of DWARF location list entries.
  (mn10300_elf_relax_delete_bytes): Stop deletion if an align reloc is encountered that is larger than or not a mutliple of the number of bytes being deleted.
  When adjusting symbols, any symbols inside the region being deleted must be moved to the end of the region.
  Move align relocs forward if there is room for them after the deletion of the region.

1 files changed, 67 insertions, 14 deletions

diff --git a/bfd/elf-m10300.c b/bfd/elf-m10300.c
index 7c51498..9a75b7c 100644
--- a/bfd/elf-m10300.c
+++ b/bfd/elf-m10300.c
@@ -1039,6 +1039,17 @@ mn10300_elf_final_link_relocate (reloc_howto_type *howto,
 	case R_MN10300_16:
 	case R_MN10300_8:
 	  value -= sym_diff_value;
+	  /* If we are computing a 32-bit value for the location lists
+	     and the result is 0 then we add one to the value.  A zero
+	     value can result because of linker relaxation deleteing
+	     prologue instructions and using a value of 1 (for the begin
+	     and end offsets in the location list entry) results in a
+	     nul entry which does not prevent the following entries from
+	     being parsed.  */
+	  if (r_type == R_MN10300_32
+	      && value == 0
+	      && strcmp (input_section->name, ".debug_loc") == 0)
+	    value = 1;
 	  sym_diff_section = NULL;
 	  is_sym_diff_reloc = TRUE;
 	  break;
@@ -1856,17 +1867,23 @@ mn10300_elf_relax_delete_bytes (bfd *abfd,
 	--irelend;
       
       /* The deletion must stop at the next ALIGN reloc for an aligment
-	 power larger than the number of bytes we are deleting.  */
+	 power larger than, or not a multiple of, the number of bytes we
+	 are deleting.  */
       for (; irel < irelend; irel++)
-	if (ELF32_R_TYPE (irel->r_info) == (int) R_MN10300_ALIGN
-	    && irel->r_offset > addr
-	    && irel->r_offset < toaddr
-	    && count < (1 << irel->r_addend))
-	  {
-	    irelalign = irel;
-	    toaddr = irel->r_offset;
-	    break;
-	  }
+	{
+	  int alignment = 1 << irel->r_addend;
+
+	  if (ELF32_R_TYPE (irel->r_info) == (int) R_MN10300_ALIGN
+	      && irel->r_offset > addr
+	      && irel->r_offset < toaddr
+	      && (count < alignment
+		  || alignment % count != 0))
+	    {
+	      irelalign = irel;
+	      toaddr = irel->r_offset;
+	      break;
+	    }
+	}
     }
 
   /* Actually delete the bytes.  */
@@ -1898,11 +1915,17 @@ mn10300_elf_relax_delete_bytes (bfd *abfd,
     {
       /* Get the new reloc address.  */
       if ((irel->r_offset > addr
-	   && irel->r_offset < toaddr))
+	   && irel->r_offset < toaddr)
+	  || (ELF32_R_TYPE (irel->r_info) == (int) R_MN10300_ALIGN
+	      && irel->r_offset == toaddr))
 	irel->r_offset -= count;
     }
 
-  /* Adjust the local symbols defined in this section.  */
+  /* Adjust the local symbols in the section, reducing their value
+     by the number of bytes deleted.  Note - symbols within the deleted
+     region are moved to the address of the start of the region, which
+     actually means that they will address the byte beyond the end of
+     the region once the deletion has been completed.  */
   symtab_hdr = &elf_tdata (abfd)->symtab_hdr;
   isym = (Elf_Internal_Sym *) symtab_hdr->contents;
   for (isymend = isym + symtab_hdr->sh_info; isym < isymend; isym++)
@@ -1910,7 +1933,12 @@ mn10300_elf_relax_delete_bytes (bfd *abfd,
       if (isym->st_shndx == sec_shndx
 	  && isym->st_value > addr
 	  && isym->st_value < toaddr)
-	isym->st_value -= count;
+	{
+	  if (isym->st_value < addr + count)
+	    isym->st_value = addr;
+	  else
+	    isym->st_value -= count;
+	}
       /* Adjust the function symbol's size as well.  */
       else if (isym->st_shndx == sec_shndx
 	       && ELF_ST_TYPE (isym->st_info) == STT_FUNC
@@ -1933,7 +1961,12 @@ mn10300_elf_relax_delete_bytes (bfd *abfd,
 	  && sym_hash->root.u.def.section == sec
 	  && sym_hash->root.u.def.value > addr
 	  && sym_hash->root.u.def.value < toaddr)
-	sym_hash->root.u.def.value -= count;
+	{
+	  if (sym_hash->root.u.def.value < addr + count)
+	    sym_hash->root.u.def.value = addr;
+	  else
+	    sym_hash->root.u.def.value -= count;
+	}
       /* Adjust the function symbol's size as well.  */
       else if (sym_hash->root.type == bfd_link_hash_defined
 	       && sym_hash->root.u.def.section == sec
@@ -1943,6 +1976,26 @@ mn10300_elf_relax_delete_bytes (bfd *abfd,
 	sym_hash->size -= count;
     }
 
+  /* See if we can move the ALIGN reloc forward.
+     We have adjusted r_offset for it already.  */
+  if (irelalign != NULL)
+    {
+      bfd_vma alignto, alignaddr;
+
+      if ((int) irelalign->r_addend > 0)
+	{
+	  /* This is the old address.  */
+	  alignto = BFD_ALIGN (toaddr, 1 << irelalign->r_addend);
+	  /* This is where the align points to now.  */
+	  alignaddr = BFD_ALIGN (irelalign->r_offset,
+				 1 << irelalign->r_addend);
+	  if (alignaddr < alignto)
+	    /* Tail recursion.  */
+	    return mn10300_elf_relax_delete_bytes (abfd, sec, alignaddr,
+						   (int) (alignto - alignaddr));
+	}
+    }
+
   return TRUE;
 }