Add linker relaxation support for the AVR

2 files changed, 43 insertions, 12 deletions

diff --git a/gas/ChangeLog b/gas/ChangeLog
index b9f53e0..1347fae 100644
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,16 @@
+2006-03-03  Bjoern Haase  <bjoern.m.haase@web.de>
+
+	* config/tc-avr.c (avr_mod_hash_value): New function.
+	(md_apply_fix, exp_mod): Use BFD_RELOC_HH8_LDI and
+	BFD_RELOC_MS8_LDI for hlo8() and hhi8() 
+	(md_begin): Set linkrelax variable to 1, use avr_mod_hash_value
+	instead of int avr_ldi_expression: use avr_mod_hash_value instead
+	of (int).
+	(tc_gen_reloc): Handle substractions of symbols, if possible do
+	fixups, abort otherwise.	
+	* config/tc-avr.h (TC_LINKRELAX_FIXUP, TC_VALIDATE_FIX,
+	tc_fix_adjustable): Define.
+	
 2006-03-02  James E Wilson  <wilson@specifix.com>
 
 	* config/tc-ia64.c (emit_one_bundle): For IA64_OPCODE_LAST, if we
diff --git a/gas/config/tc-avr.c b/gas/config/tc-avr.c
index 2ceaa1f..d6294f3 100644
--- a/gas/config/tc-avr.c
+++ b/gas/config/tc-avr.c
@@ -170,8 +170,8 @@ static struct exp_mod_s exp_mod[] =
   {"pm_hi8", BFD_RELOC_AVR_HI8_LDI_PM, BFD_RELOC_AVR_HI8_LDI_PM_NEG, 0},
   {"lo8",    BFD_RELOC_AVR_LO8_LDI,    BFD_RELOC_AVR_LO8_LDI_NEG,    1},
   {"pm_lo8", BFD_RELOC_AVR_LO8_LDI_PM, BFD_RELOC_AVR_LO8_LDI_PM_NEG, 0},
-  {"hlo8",   -BFD_RELOC_AVR_LO8_LDI,   -BFD_RELOC_AVR_LO8_LDI_NEG,   0},
-  {"hhi8",   -BFD_RELOC_AVR_HI8_LDI,   -BFD_RELOC_AVR_HI8_LDI_NEG,   0},
+  {"hlo8",   BFD_RELOC_AVR_HH8_LDI,    BFD_RELOC_AVR_HH8_LDI_NEG,    0},
+  {"hhi8",   BFD_RELOC_AVR_MS8_LDI,    BFD_RELOC_AVR_MS8_LDI_NEG,    0},
 };
 
 /* A union used to store indicies into the exp_mod[] array
@@ -1081,15 +1081,11 @@ md_apply_fix (fixS *fixP, valueT * valP, segT seg)
 	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value), where);
 	  break;
 
-	case -BFD_RELOC_AVR_LO8_LDI:
-	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 16), where);
-	  break;
-
 	case BFD_RELOC_AVR_HI8_LDI:
 	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 8), where);
 	  break;
 
-	case -BFD_RELOC_AVR_HI8_LDI:
+	case BFD_RELOC_AVR_MS8_LDI:
 	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (value >> 24), where);
 	  break;
 
@@ -1101,15 +1097,11 @@ md_apply_fix (fixS *fixP, valueT * valP, segT seg)
 	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value), where);
 	  break;
 
-	case -BFD_RELOC_AVR_LO8_LDI_NEG:
-	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 16), where);
-	  break;
-
 	case BFD_RELOC_AVR_HI8_LDI_NEG:
 	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 8), where);
 	  break;
 
-	case -BFD_RELOC_AVR_HI8_LDI_NEG:
+	case BFD_RELOC_AVR_MS8_LDI_NEG:
 	  bfd_putl16 ((bfd_vma) insn | LDI_IMMEDIATE (-value >> 24), where);
 	  break;
 
@@ -1195,6 +1187,32 @@ tc_gen_reloc (asection *seg ATTRIBUTE_UNUSED,
 {
   arelent *reloc;
 
+  if (fixp->fx_addsy && fixp->fx_subsy)
+    {
+      long value = 0;
+
+      if ((S_GET_SEGMENT (fixp->fx_addsy) != S_GET_SEGMENT (fixp->fx_subsy))
+          || S_GET_SEGMENT (fixp->fx_addsy) == undefined_section)
+        {
+          as_bad_where (fixp->fx_file, fixp->fx_line,
+              "Difference of symbols in different sections is not supported");
+          return NULL;
+        }
+
+      /* We are dealing with two symbols defined in the same section. 
+         Let us fix-up them here.  */
+      value += S_GET_VALUE (fixp->fx_addsy);
+      value -= S_GET_VALUE (fixp->fx_subsy);
+
+      /* When fx_addsy and fx_subsy both are zero, md_apply_fix
+         only takes it's second operands for the fixup value.  */
+      fixp->fx_addsy = NULL;
+      fixp->fx_subsy = NULL;
+      md_apply_fix (fixp, (valueT *) &value, NULL);
+
+      return NULL;
+    }
+
   reloc = xmalloc (sizeof (arelent));
 
   reloc->sym_ptr_ptr = xmalloc (sizeof (asymbol *));