* readelf.c (get_machine_dlags): Add support for RX's PID mode.

	* ld-scripts/phdrs.exp: Expect to fail for the RX.

	* elf32-rx.c: Add support for PID mode.
	(rx_elf_relocate_section): Add checks for unsafe PID relocations.
	Include addend in R_RX_SYM relocations.

	* config/rx-defs.h (rx_pid_register): New.
	(rx_gp_register): New.
	* config/rx-parse.y (rx_lex): Add support for %gpreg and %pidreg.
	(displacement): Add PID support.
	* config/tc-rx.c (rx_pid_mode): New.
	(rx_num_int_regs): New.
	(rx_pid_register): New.
	(rx_gp_register): New.
	(options): Add -mpid and -mint-register= options.
	(md_longopts): Likewise.
	(md_parse_option): Likewise.
	(md_show_usage): Likewise.
	(rx_pid_symbol): New.
	(rx_pidreg_symbol): New.
	(rx_gpreg_symbol): New.
	(md_begin): Support PID.
	(rx_validate_fix_sub): Support PID.
	(tc_gen_reloc): Support PID.
	* doc/c-rx.texi: Document PID support.

	* rx.h (E_FLAG_RX_PID): New.

5 files changed, 166 insertions, 19 deletions

diff --git a/gas/ChangeLog b/gas/ChangeLog
index 79f7cac..958b401 100644
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,26 @@
+2011-10-05  DJ Delorie  <dj@redhat.com>
+	    Nick Clifton  <nickc@redhat.com>
+
+	* config/rx-defs.h (rx_pid_register): New.
+	(rx_gp_register): New.
+	* config/rx-parse.y (rx_lex): Add support for %gpreg and %pidreg.
+	(displacement): Add PID support.
+	* config/tc-rx.c (rx_pid_mode): New.
+	(rx_num_int_regs): New.
+	(rx_pid_register): New.
+	(rx_gp_register): New.
+	(options): Add -mpid and -mint-register= options.
+	(md_longopts): Likewise.
+	(md_parse_option): Likewise.
+	(md_show_usage): Likewise.
+	(rx_pid_symbol): New.
+	(rx_pidreg_symbol): New.
+	(rx_gpreg_symbol): New.
+	(md_begin): Support PID.
+	(rx_validate_fix_sub): Support PID.
+	(tc_gen_reloc): Support PID.
+	* doc/c-rx.texi: Document PID support.
+
 2011-09-27  Kai Tietz  <ktietz@redhat.com>
 
 	* config/obj-coff.c (obj_coff_section): Add 'e' as specifier
diff --git a/gas/config/rx-defs.h b/gas/config/rx-defs.h
index c4648d2..868796e 100644
--- a/gas/config/rx-defs.h
+++ b/gas/config/rx-defs.h
@@ -34,6 +34,9 @@
 #define RX_RELAX_IMM	2
 #define RX_RELAX_DISP	3
 
+extern int rx_pid_register;
+extern int rx_gp_register;
+
 extern int    rx_error (char *);
 extern void   rx_lex_init (char *, char *);
 extern void   rx_base1 (int);
diff --git a/gas/config/rx-parse.y b/gas/config/rx-parse.y
index 2d1f85e..b473788 100644
--- a/gas/config/rx-parse.y
+++ b/gas/config/rx-parse.y
@@ -1170,6 +1170,8 @@ rx_lex (void)
     return 0;
 
   if (ISALPHA (*rx_lex_start)
+      || (rx_pid_register != -1 && memcmp (rx_lex_start, "%pidreg", 7) == 0)
+      || (rx_gp_register != -1 && memcmp (rx_lex_start, "%gpreg", 6) == 0)
       || (*rx_lex_start == '.' && ISALPHA (rx_lex_start[1])))
     {
       unsigned int i;
@@ -1183,6 +1185,28 @@ rx_lex (void)
       save = *e;
       *e = 0;
 
+      if (strcmp (rx_lex_start, "%pidreg") == 0)
+	{
+	  {
+	    rx_lval.regno = rx_pid_register;
+	    *e = save;
+	    rx_lex_start = e;
+	    rx_last_token = REG;
+	    return REG;
+	  }
+	}
+
+      if (strcmp (rx_lex_start, "%gpreg") == 0)
+	{
+	  {
+	    rx_lval.regno = rx_gp_register;
+	    *e = save;
+	    rx_lex_start = e;
+	    rx_last_token = REG;
+	    return REG;
+	  }
+	}
+
       if (rx_last_token == 0)
 	for (ci = 0; ci < NUM_CONDITION_OPCODES; ci ++)
 	  if (check_condition (condition_opcode_table[ci].string))
@@ -1482,6 +1506,13 @@ displacement (expressionS exp, int msize)
 	}
     }
 
+  if (exp.X_op == O_subtract)
+    {
+      exp.X_md = BFD_RELOC_RX_DIFF;
+      O2 (exp);
+      return 2;
+    }
+
   if (exp.X_op != O_constant)
     {
       rx_error (_("displacements must be constants"));
diff --git a/gas/config/tc-rx.c b/gas/config/tc-rx.c
index 56cda15..4fa0f67 100644
--- a/gas/config/tc-rx.c
+++ b/gas/config/tc-rx.c
@@ -1,5 +1,5 @@
 /* tc-rx.c -- Assembler for the Renesas RX
-   Copyright 2008, 2009, 2010
+   Copyright 2008, 2009, 2010, 2011
    Free Software Foundation, Inc.
 
    This file is part of GAS, the GNU Assembler.
@@ -51,6 +51,11 @@ static int elf_flags = 0;
 bfd_boolean rx_use_conventional_section_names = FALSE;
 static bfd_boolean rx_use_small_data_limit = FALSE;
 
+static bfd_boolean rx_pid_mode = FALSE;
+static int rx_num_int_regs = 0;
+int rx_pid_register;
+int rx_gp_register;
+
 enum options
 {
   OPTION_BIG = OPTION_MD_BASE,
@@ -60,7 +65,9 @@ enum options
   OPTION_CONVENTIONAL_SECTION_NAMES,
   OPTION_RENESAS_SECTION_NAMES,
   OPTION_SMALL_DATA_LIMIT,
-  OPTION_RELAX
+  OPTION_RELAX,
+  OPTION_PID,
+  OPTION_INT_REGS,
 };
 
 #define RX_SHORTOPTS ""
@@ -83,6 +90,8 @@ struct option md_longopts[] =
   {"muse-renesas-section-names", no_argument, NULL, OPTION_RENESAS_SECTION_NAMES},
   {"msmall-data-limit", no_argument, NULL, OPTION_SMALL_DATA_LIMIT},
   {"relax", no_argument, NULL, OPTION_RELAX},
+  {"mpid", no_argument, NULL, OPTION_PID},
+  {"mint-register", required_argument, NULL, OPTION_INT_REGS},
   {NULL, no_argument, NULL, 0}
 };
 size_t md_longopts_size = sizeof (md_longopts);
@@ -123,6 +132,15 @@ md_parse_option (int c ATTRIBUTE_UNUSED, char * arg ATTRIBUTE_UNUSED)
     case OPTION_RELAX:
       linkrelax = 1;
       return 1;
+
+    case OPTION_PID:
+      rx_pid_mode = TRUE;
+      elf_flags |= E_FLAG_RX_PID;
+      return 1;
+
+    case OPTION_INT_REGS:
+      rx_num_int_regs = atoi (optarg);
+      return 1;
     }
   return 0;
 }
@@ -138,6 +156,9 @@ md_show_usage (FILE * stream)
   fprintf (stream, _("  --muse-conventional-section-names\n"));
   fprintf (stream, _("  --muse-renesas-section-names [default]\n"));
   fprintf (stream, _("  --msmall-data-limit\n"));
+  fprintf (stream, _("  --mrelax\n"));
+  fprintf (stream, _("  --mpid\n"));
+  fprintf (stream, _("  --mint-register=<value>\n"));
 }
 
 static void
@@ -584,16 +605,44 @@ const pseudo_typeS md_pseudo_table[] =
 };
 
 static asymbol * gp_symbol;
+static asymbol * rx_pid_symbol;
+
+static symbolS * rx_pidreg_symbol;
+static symbolS * rx_gpreg_symbol;
 
 void
 md_begin (void)
 {
+  /* Make the __gp and __pid_base symbols now rather
+     than after the symbol table is frozen.  We only do this
+     when supporting small data limits because otherwise we
+     pollute the symbol table.  */
+
+  /* The meta-registers %pidreg and %gpreg depend on what other
+     options are specified.  The __rx_*_defined symbols exist so we
+     can .ifdef asm code based on what options were passed to gas,
+     without needing a preprocessor  */
+
+  if (rx_pid_mode)
+    {
+      rx_pid_register = 13 - rx_num_int_regs;
+      rx_pid_symbol = symbol_get_bfdsym (symbol_find_or_make ("__pid_base"));
+      rx_pidreg_symbol = symbol_find_or_make ("__rx_pidreg_defined");
+      S_SET_VALUE (rx_pidreg_symbol, rx_pid_register);
+      S_SET_SEGMENT (rx_pidreg_symbol, absolute_section);
+    }
+
   if (rx_use_small_data_limit)
-    /* Make the __gp symbol now rather
-       than after the symbol table is frozen.  We only do this
-       when supporting small data limits because otherwise we
-       pollute the symbol table.  */
-    gp_symbol = symbol_get_bfdsym (symbol_find_or_make ("__gp"));
+    {
+      if (rx_pid_mode)
+	rx_gp_register = rx_pid_register - 1;
+      else
+	rx_gp_register = 13 - rx_num_int_regs;
+      gp_symbol = symbol_get_bfdsym (symbol_find_or_make ("__gp"));
+      rx_gpreg_symbol = symbol_find_or_make ("__rx_gpreg_defined");
+      S_SET_VALUE (rx_gpreg_symbol, rx_gp_register);
+      S_SET_SEGMENT (rx_gpreg_symbol, absolute_section);
+    }
 }
 
 char * rx_lex_start;
@@ -1150,7 +1199,7 @@ rx_handle_align (fragS * frag)
       && subseg_text_p (now_seg))
     {
       int count = (frag->fr_next->fr_address
-		   - frag->fr_address	
+		   - frag->fr_address
 		   - frag->fr_fix);
       unsigned char *base = (unsigned char *)frag->fr_literal + frag->fr_fix;
 
@@ -2222,10 +2271,10 @@ md_apply_fix (struct fix * f ATTRIBUTE_UNUSED,
 }
 
 arelent **
-tc_gen_reloc (asection * seg ATTRIBUTE_UNUSED, fixS * fixp)
+tc_gen_reloc (asection * sec ATTRIBUTE_UNUSED, fixS * fixp)
 {
   static arelent * reloc[5];
-  int is_opcode = 0;
+  bfd_boolean is_opcode = FALSE;
 
   if (fixp->fx_r_type == BFD_RELOC_NONE)
     {
@@ -2250,9 +2299,11 @@ tc_gen_reloc (asection * seg ATTRIBUTE_UNUSED, fixS * fixp)
       && fixp->fx_subsy)
     {
       fixp->fx_r_type = BFD_RELOC_RX_DIFF;
-      is_opcode = 1;
+      is_opcode = TRUE;
     }
-
+  else if (sec)
+    is_opcode = sec->flags & SEC_CODE;
+      
   /* Certain BFD relocations cannot be translated directly into
      a single (non-Red Hat) RX relocation, but instead need
      multiple RX relocations - handle them here.  */
@@ -2283,6 +2334,8 @@ tc_gen_reloc (asection * seg ATTRIBUTE_UNUSED, fixS * fixp)
 	case 2:
 	  if (!is_opcode && target_big_endian)
 	    reloc[3]->howto   = bfd_reloc_type_lookup (stdoutput, BFD_RELOC_RX_ABS16_REV);
+	  else if (is_opcode)
+	    reloc[3]->howto   = bfd_reloc_type_lookup (stdoutput, BFD_RELOC_RX_ABS16UL);
 	  else
 	    reloc[3]->howto   = bfd_reloc_type_lookup (stdoutput, BFD_RELOC_RX_ABS16);
 	  break;
diff --git a/gas/doc/c-rx.texi b/gas/doc/c-rx.texi
index 183fbe3..cb89bd6 100644
--- a/gas/doc/c-rx.texi
+++ b/gas/doc/c-rx.texi
@@ -74,11 +74,25 @@ This is the default.
 @item -msmall-data-limit
 This option tells the assembler that the small data limit feature of
 the RX port of GCC is being used.  This results in the assembler
-generating an undefined reference to a symbol called __gp for use by
-the relocations that are needed to support the small data limit
+generating an undefined reference to a symbol called @code{__gp} for
+use by the relocations that are needed to support the small data limit
 feature.   This option is not enabled by default as it would otherwise
 pollute the symbol table.
 
+@cindex @samp{-mpid}
+@item -mpid
+This option tells the assembler that the position independent data of the
+RX port of GCC is being used.  This results in the assembler
+generating an undefined reference to a symbol called @code{__pid_base},
+and also setting the RX_PID flag bit in the e_flags field of the ELF
+header of the object file.
+
+@cindex @samp{-mint-register}
+@item -mint-register=@var{num}
+This option tells the assembler how many registers have been reserved
+for use by interrupt handlers.  This is needed in order to compute the
+correct values for the @code{%gpreg} and @code{%pidreg} meta registers.
+
 @end table
 
 @node RX-Modifiers
@@ -86,22 +100,45 @@ pollute the symbol table.
 
 @cindex RX modifiers
 @cindex syntax, RX
+@cindex %gp
 
-The assembler supports several modifiers when using symbol addresses
+The assembler supports one modifier when using symbol addresses
 in RX instruction operands.  The general syntax is the following:
 
 @smallexample
-%modifier(symbol)
+%gp(symbol)
 @end smallexample
 
+The modifier returns the offset from the @var{__gp} symbol to the
+specified symbol as a 16-bit value.  The intent is that this offset
+should be used in a register+offset move instruction when generating
+references to small data.  Ie, like this:
+
+@smallexample
+  mov.W	 %gp(_foo)[%gpreg], r1
+@end smallexample
+
+The assembler also supports two meta register names which can be used
+to refer to registers whose values may not be known to the
+programmer.  These meta register names are:
+
 @table @code
-@cindex symbol modifiers
 
-@item %gp
-@c FIXME: Add documentation here.
+@cindex @samp{%gpreg}
+@item %gpreg
+The small data address register.
+
+@cindex @samp{%pidreg}
+@item %pidreg
+The PID base address register.
 
 @end table
 
+Both registers normally have the value r13, but this can change if
+some registers have been reserved for use by interrupt handlers or if
+both the small data limit and position independent data features are
+being used at the same time.
+
 @node RX-Directives
 @section Assembler Directives