Adds support to the RL78 port for linker relaxation affecting .debug sections.

gas	* config/tc-rl78.h (TC_LINKRELAX_FIXUP): Define.
	(TC_FORCE_RELOCATION_SUB_SAME): Define.
	(DWARF2_USE_FIXED_ADVANCE_PC): Define.

	* gas/lns/lns.exp: Add RL78 to list of targets using
	DW_LNS_fixed_advance_pc.

bfd	* elf32-rl78.c (RL78_OP_REL): New macro.
	(rl78_elf_howto_table): Use it for complex relocs.
	(get_symbol_value): Handle the cases when the info or status
	arguments are NULL.
	(get_romstart): Cache the status returned by get_symbol_value.
	(get_ramstart): Likewise.
	(RL78_STACK_PUSH): Generate an error message if the stack
	overflows.
	(RL78_STACK_POP): Likewise for underflows.
	(rl78_compute_complex_reloc): New function.  Contains the basic
	processing code for all RL78 complex relocs.
	(rl78_special_reloc): New function.  Provides special reloc
	handling for complex relocs.
	(rl78_elf_relocate_section): Use rl78_compute_complex_reloc.
	(rl78_offset_for_reloc): Likewise.

binutils* readelf.c (target_specific_reloc_handling): Add code to handle
	RL78 complex relocs.

2 files changed, 34 insertions, 9 deletions

diff --git a/gas/config/tc-rl78.c b/gas/config/tc-rl78.c
index 337b819..b5f0563 100644
--- a/gas/config/tc-rl78.c
+++ b/gas/config/tc-rl78.c
@@ -340,15 +340,16 @@ md_parse_option (int c, char * arg ATTRIBUTE_UNUSED)
 }
 
 void
-md_show_usage (FILE * stream ATTRIBUTE_UNUSED)
+md_show_usage (FILE * stream)
 {
   fprintf (stream, _(" RL78 specific command line options:\n"));
+  fprintf (stream, _("  --mrelax          Enable link time relaxation\n"));
   fprintf (stream, _("  --mg10            Enable support for G10 variant\n"));
   fprintf (stream, _("  --mg13            Selects the G13 core.\n"));
   fprintf (stream, _("  --mg14            Selects the G14 core [default]\n"));
   fprintf (stream, _("  --mrl78           Alias for --mg14\n"));
   fprintf (stream, _("  --m32bit-doubles  [default]\n"));
-  fprintf (stream, _("  --m64bit-doubles\n"));
+  fprintf (stream, _("  --m64bit-doubles  Source code uses 64-bit doubles\n"));
 }
 
 static void
@@ -662,13 +663,23 @@ rl78_cons_fix_new (fragS *	frag,
     case BFD_RELOC_RL78_LO16:
     case BFD_RELOC_RL78_HI16:
       if (size != 2)
-	as_bad (_("%%hi16/%%lo16 only applies to .short or .hword"));
-      type = exp->X_md;
+	{
+	  /* Fixups to assembler generated expressions do not use %hi or %lo.  */
+	  if (frag->fr_file)
+	    as_bad (_("%%hi16/%%lo16 only applies to .short or .hword"));
+	}
+      else
+	type = exp->X_md;
       break;
     case BFD_RELOC_RL78_HI8:
       if (size != 1)
-	as_bad (_("%%hi8 only applies to .byte"));
-      type = exp->X_md;
+	{
+	  /* Fixups to assembler generated expressions do not use %hi or %lo.  */
+	  if (frag->fr_file)
+	    as_bad (_("%%hi8 only applies to .byte"));
+	}
+      else
+	type = exp->X_md;
       break;
     default:
       break;
@@ -823,7 +834,7 @@ rl78_frag_fix_value (fragS *    fragP,
 /* Estimate how big the opcode is after this relax pass.  The return
    value is the difference between fr_fix and the actual size.  We
    compute the total size in rl78_relax_frag and store it in fr_subtype,
-   sowe only need to subtract fx_fix and return it.  */
+   so we only need to subtract fx_fix and return it.  */
 
 int
 md_estimate_size_before_relax (fragS * fragP ATTRIBUTE_UNUSED, segT segment ATTRIBUTE_UNUSED)
@@ -960,8 +971,8 @@ rl78_relax_frag (segT segment ATTRIBUTE_UNUSED, fragS * fragP, long stretch)
   fragP->fr_subtype = newsize;
   tprintf (" -> new %d old %d delta %d\n", newsize, oldsize, newsize-oldsize);
   return newsize - oldsize;
- }
- 
+}
+
 /* This lets us test for the opcode type and the desired size in a
    switch statement.  */
 #define OPCODE(type,size) ((type) * 16 + (size))
diff --git a/gas/config/tc-rl78.h b/gas/config/tc-rl78.h
index e2b9699..b9ede61 100644
--- a/gas/config/tc-rl78.h
+++ b/gas/config/tc-rl78.h
@@ -85,3 +85,17 @@ extern void rl78_elf_final_processing (void);
 
 #define TC_PARSE_CONS_EXPRESSION(EXP, NBYTES)	\
   ((EXP)->X_md = 0, expression (EXP), TC_PARSE_CONS_RETURN_NONE)
+
+#define TC_LINKRELAX_FIXUP(seg) ((seg->flags & SEC_CODE) || (seg->flags & SEC_DEBUGGING))
+
+/* Do not adjust relocations involving symbols in code sections,
+   because it breaks linker relaxations.  This could be fixed in the
+   linker, but this fix is simpler, and it pretty much only affects
+   object size a little bit.  */
+#define TC_FORCE_RELOCATION_SUB_SAME(FIX, SEC)	\
+  (   ((SEC)->flags & SEC_CODE) != 0		\
+   || ((SEC)->flags & SEC_DEBUGGING) != 0	\
+   || ! SEG_NORMAL (SEC)			\
+   || TC_FORCE_RELOCATION (FIX))
+
+#define DWARF2_USE_FIXED_ADVANCE_PC 1