This is the mail archive of the binutils@sourceware.org mailing list for the binutils project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

RE: [PATCH] Avr Linker relaxation followup - spam filter


You wrote Samstag, 22. April 2006 11:22 :
> Hi Bj?rn,
>
> > The attached mail had been blocked by your spam filter.
> >
> > 2006-04-19 ? Bjoern Haase ? <bjoern.m.haase@web.de>
> >
> > ? ? ? ? ? ? ? ? * bfd/elf32-avr.c:
> > ?  ?  ?  ?  elf32_avr_relax_delete_bytes:
> > 	Iterate over all of the bfd's sections for reloc-addend adjustments.
> >
> > ? ? ? ? ? ? ? ? * gas/config/tc-avr.h:
> > ? ? ? ? ? ? ? ? TC_VALIDATE_FIX: add.
>
> My guess is that it is this part of the email that is triggering the
> spam filter.  There are lots of characters that show up in this entry as
> a capital A with a circumflex ^ over it.  (At least in my email reader).
>
> Can you try changing your character set and then creating a new
> ChangeLog entry for the email ?
>
> Cheers
>    Nick
Thank's for your reply.

Dunno, It seems that finally the mail got through the filter despite the 
message I got from the list daemon: today, I could see it in the list 
archive.

So here again is the change log entry and the patch. Since the present CVS 
state is broken as is the current pre-release, I'd like to suggest that it 
would be best to apply this patch also in the 2.17 branch.

Yours,

Bjoern.

2006-04-19	Bjoern Haase	<bjoern.m.haase@web.de>

	* bfd/elf32-avr.c:
	elf32_avr_relax_delete_bytes:
	Iterate over all of the bfd's sections for the reloc-addend adjustments.

	* gas/config/tc-avr.h:
	TC_VALIDATE_FIX: disable fixups for PMEM related expressions
Index: bfd/elf32-avr.c
===================================================================
RCS file: /cvs/src/src/bfd/elf32-avr.c,v
retrieving revision 1.24
diff -U12 -r1.24 elf32-avr.c
--- bfd/elf32-avr.c	3 Mar 2006 15:54:23 -0000	1.24
+++ bfd/elf32-avr.c	20 Apr 2006 07:10:59 -0000
@@ -1040,27 +1040,27 @@
 
 
 /* Enable debugging printout at stdout with a value of 1.  */
 #define DEBUG_RELAX 0
 
 /* 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.  */
 
 static bfd_boolean
 elf32_avr_relax_delete_bytes (bfd *abfd,
-			      asection *sec,
+                              asection *sec,
                               bfd_vma addr,
-			      int count)
+                              int count)
 {
   Elf_Internal_Shdr *symtab_hdr;
   unsigned int sec_shndx;
   bfd_byte *contents;
   Elf_Internal_Rela *irel, *irelend;
   Elf_Internal_Rela *irelalign;
   Elf_Internal_Sym *isym;
   Elf_Internal_Sym *isymbuf = NULL;
   Elf_Internal_Sym *isymend;
   bfd_vma toaddr;
   struct elf_link_hash_entry **sym_hashes;
   struct elf_link_hash_entry **end_hashes;
@@ -1076,113 +1076,139 @@
   irelalign = NULL;
   toaddr = sec->size;
 
   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;
 
-  /* Adjust all the relocs.  */
+  /* Adjust all the reloc addresses.  */
   for (irel = elf_section_data (sec)->relocs; irel < irelend; irel++)
     {
-      bfd_vma symval;
       bfd_vma old_reloc_address;
       bfd_vma shrinked_insn_address;
 
       old_reloc_address = (sec->output_section->vma
                            + sec->output_offset + irel->r_offset);
       shrinked_insn_address = (sec->output_section->vma
                               + sec->output_offset + addr - count);
 
       /* Get the new reloc address.  */
       if ((irel->r_offset > addr
            && irel->r_offset < toaddr))
         {
           if (DEBUG_RELAX)
             printf ("Relocation at address 0x%x needs to be moved.\n"
                     "Old section offset: 0x%x, New section offset: 0x%x \n",
                     (unsigned int) old_reloc_address,
                     (unsigned int) irel->r_offset,
                     (unsigned int) ((irel->r_offset) - count));
 
           irel->r_offset -= count;
         }
 
-      /* The reloc's own addresses are now ok. However, we need to readjust
-         the reloc's addend if two conditions are met:
-         1.) the reloc is relative to a symbol in this section that
-             is located in front of the shrinked instruction
-         2.) symbol plus addend end up behind the shrinked instruction.
-
-         This should happen only for local symbols that are progmem related.  */
-
-      /* Read this BFD's local symbols if we haven't done so already.  */
-      if (isymbuf == NULL && symtab_hdr->sh_info != 0)
-        {
-          isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
-          if (isymbuf == NULL)
-            isymbuf = bfd_elf_get_elf_syms (abfd, symtab_hdr,
-                                            symtab_hdr->sh_info, 0,
-                                            NULL, NULL, NULL);
-          if (isymbuf == NULL)
-             return FALSE;
-         }
-
-      /* Get the value of the symbol referred to by the reloc.  */
-      if (ELF32_R_SYM (irel->r_info) < symtab_hdr->sh_info)
-        {
-          /* A local symbol.  */
-          Elf_Internal_Sym *isym;
-          asection *sym_sec;
-
-          isym = isymbuf + ELF32_R_SYM (irel->r_info);
-          sym_sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
-          symval = isym->st_value;
-          /* If the reloc is absolute, it will not have
-             a symbol or section associated with it.  */
-          if (sym_sec)
-            {
-               symval += sym_sec->output_section->vma
-                         + sym_sec->output_offset;
-
-               if (DEBUG_RELAX)
-                printf ("Checking if the relocation's "
-                        "addend needs corrections.\n"
-                        "Address of anchor symbol: 0x%x \n"
-                        "Address of relocation target: 0x%x \n"
-                        "Address of relaxed insn: 0x%x \n",
-                        (unsigned int) symval,
-                        (unsigned int) (symval + irel->r_addend),
-                        (unsigned int) shrinked_insn_address);
+    }
 
-               if (symval <= shrinked_insn_address
-                   && (symval + irel->r_addend) > shrinked_insn_address)
-                 {
-                   irel->r_addend -= count;
+   /* The reloc's own addresses are now ok. However, we need to readjust
+      the reloc's addend, i.e. the reloc's value if two conditions are met:
+      1.) the reloc is relative to a symbol in this section that
+          is located in front of the shrinked instruction
+      2.) symbol plus addend end up behind the shrinked instruction.  
+      
+      The most common case where this happens are relocs relative to
+      the section-start symbol.
+         
+      This step needs to be done for all of the sections of the bfd.  */
+
+  {
+    struct bfd_section *isec;
+    for (isec = abfd->sections; isec; isec = isec->next)
+     {
+       bfd_vma symval;
+       bfd_vma shrinked_insn_address;
+
+       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 < irelend;
+            irel++)
+         {
+           /* Read this BFD's local symbols if we haven't done 
+              so already.  */
+           if (isymbuf == NULL && symtab_hdr->sh_info != 0)
+             {
+               isymbuf = (Elf_Internal_Sym *) symtab_hdr->contents;
+               if (isymbuf == NULL)
+                 isymbuf = bfd_elf_get_elf_syms (abfd, symtab_hdr,
+                                                 symtab_hdr->sh_info, 0,
+                                                 NULL, NULL, NULL);
+               if (isymbuf == NULL)
+                 return FALSE;
+             }
+
+           /* Get the value of the symbol referred to by the reloc.  */
+           if (ELF32_R_SYM (irel->r_info) < symtab_hdr->sh_info)
+             {
+               /* A local symbol.  */
+               Elf_Internal_Sym *isym;
+               asection *sym_sec;
+
+               isym = isymbuf + ELF32_R_SYM (irel->r_info);
+               sym_sec = bfd_section_from_elf_index (abfd, isym->st_shndx);
+               symval = isym->st_value;
+               /* If the reloc is absolute, it will not have
+                  a symbol or section associated with it.  */
+               if (sym_sec == sec)
+                 { 
+                   symval += sym_sec->output_section->vma
+                             + sym_sec->output_offset;
 
                    if (DEBUG_RELAX)
-                     printf ("Anchor symbol and relocation target bracket "
-                             "shrinked insn address.\n"
-                             "Need for new addend : 0x%x\n",
-                             (unsigned int) irel->r_addend);
+                     printf ("Checking if the relocation's "
+                             "addend needs corrections.\n"
+                             "Address of anchor symbol: 0x%x \n"
+                             "Address of relocation target: 0x%x \n"
+                             "Address of relaxed insn: 0x%x \n",
+                             (unsigned int) symval,
+                             (unsigned int) (symval + irel->r_addend),
+                             (unsigned int) shrinked_insn_address);
+
+                   if (symval <= shrinked_insn_address
+                       && (symval + irel->r_addend) > shrinked_insn_address)
+                     {
+                       irel->r_addend -= count;
+
+                       if (DEBUG_RELAX)
+                         printf ("Relocation's addend needed to be fixed \n");
+                     }
                  }
-            }
-	  /* else ... Reference symbol is absolute.  No adjustment needed.  */
-        }
-      /* else ... Reference symbol is extern. No need for adjusting the addend.  */
-    }
+               else
+                 {
+                   /* Reference symbol is absolute.  No adjustment needed.  */
+                 }
+              }
+            else
+              {
+                /* Reference symbol is extern. No need for adjusting 
+                   the addend.  */
+              }
+          }
+     }
+  }
 
   /* Adjust the local symbols defined in this section.  */
   isym = (Elf_Internal_Sym *) symtab_hdr->contents;
   isymend = isym + symtab_hdr->sh_info;
   for (; isym < isymend; isym++)
     {
       if (isym->st_shndx == sec_shndx
           && isym->st_value > addr
           && isym->st_value < toaddr)
         isym->st_value -= count;
     }
 
Index: gas/config/tc-avr.h
===================================================================
RCS file: /cvs/src/src/gas/config/tc-avr.h,v
retrieving revision 1.11
diff -U12 -r1.11 tc-avr.h
--- gas/config/tc-avr.h	12 Oct 2005 10:56:46 -0000	1.11
+++ gas/config/tc-avr.h	20 Apr 2006 07:11:01 -0000
@@ -111,12 +111,29 @@
 
 /* AVR port uses `$' as a logical line separator */
 #define LEX_DOLLAR 0
 
 /* An `.lcomm' directive with no explicit alignment parameter will
    use this macro to set P2VAR to the alignment that a request for
    SIZE bytes will have.  The alignment is expressed as a power of
    two.  If no alignment should take place, the macro definition
    should do nothing.  Some targets define a `.bss' directive that is
    also affected by this macro.  The default definition will set
    P2VAR to the truncated power of two of sizes up to eight bytes.  */
 #define TC_IMPLICIT_LCOMM_ALIGNMENT(SIZE, P2VAR) (P2VAR) = 0
+
+/* We don't want gas to fixup the following program memory related relocations.
+   We will need them in case that we want to do linker relaxation.
+   We could in principle keep these fixups in gas when not relaxing.
+   However, there is no serious performance penilty when making the linker
+   make the fixup work. */
+#define TC_VALIDATE_FIX(FIXP,SEG,SKIP)                      \
+if (FIXP->fx_r_type == BFD_RELOC_AVR_7_PCREL                \
+    || FIXP->fx_r_type == BFD_RELOC_AVR_13_PCREL            \
+    || FIXP->fx_r_type == BFD_RELOC_AVR_LO8_LDI_PM          \
+    || FIXP->fx_r_type == BFD_RELOC_AVR_HI8_LDI_PM          \
+    || FIXP->fx_r_type == BFD_RELOC_AVR_HH8_LDI_PM          \
+    || FIXP->fx_r_type == BFD_RELOC_AVR_16_PM)              \
+  {                                                         \
+     goto SKIP;                                             \
+  }
+

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]