* read.c (potable): Add "mri" and ".mri".

	(s_mri): New function.
	* read.h (s_mri): Declare.
	* app.c (scrub_m68k_mri): New static variable.
	(mri_pseudo): New static variable.
	(do_scrub_begin): Add m68k_mri parameter.  Use it rather than
	flag_m68k_mri.  Initialize scrub_m68k_mri.
	(mri_state, mri_last_ch): New static variables.
	(struct app_save): Add scrub_m68k_mri, mri_state, and mri_last_ch
	fields.
	(app_push): Save new fields.
	(app_pop): Restore new fields.
	(do_scrub_chars): Check scrub_m68k_mri rather than flag_mri_mri.
	If TC_M68K, use a trivial state machine to look for occurrences of
	the .mri pseudo-op, and change the mode appropriately.
	* as.h (do_scrub_begin): Update prototype.
	* input-scrub.c (input_scrub_begin): Pass flag_m68k_mri to
	do_scrub_begin.
	* config/tc-m68k.c (reg_prefix_optional_seen): New static
	variable.
	(m68k_mri_mode_change): New function.
	(md_parse_option): Set reg_prefix_optional_seen.
	* config/tc-m68k.h (m68k_mri_mode_change): Declare.
	(MRI_MODE_CHANGE): Define.
	* doc/as.texinfo: Document .mri pseudo-op.

2 files changed, 44 insertions, 0 deletions

diff --git a/gas/config/tc-m68k.c b/gas/config/tc-m68k.c
index 8b31283..5235db4 100644
--- a/gas/config/tc-m68k.c
+++ b/gas/config/tc-m68k.c
@@ -74,6 +74,9 @@ int flag_reg_prefix_optional = REGISTER_PREFIX_OPTIONAL;
 int flag_reg_prefix_optional;
 #endif
 
+/* Whether --register-prefix-optional was used on the command line.  */
+static int reg_prefix_optional_seen;
+
 /* The floating point coprocessor to use by default.  */
 static enum m68k_register m68k_float_copnum = COP1;
 
@@ -3488,6 +3491,43 @@ m68k_init_after_args ()
     md_relax_table[TAB (PCINDEX, BYTE)].rlx_more = 0;
 }
 
+/* This is called if we go in or out of MRI mode because of the .mri
+   pseudo-op.  */
+
+void
+m68k_mri_mode_change (on)
+     int on;
+{
+  if (on)
+    {
+      if (! flag_reg_prefix_optional)
+	{
+	  flag_reg_prefix_optional = 1;
+#ifdef REGISTER_PREFIX
+	  init_regtable ();
+#endif
+	}
+      m68k_abspcadd = 1;
+      m68k_rel32 = 0;
+    }
+  else
+    {
+      if (! reg_prefix_optional_seen)
+	{
+#ifdef REGISTER_PREFIX_OPTIONAL
+	  flag_reg_prefix_optional = REGISTER_PREFIX_OPTIONAL;
+#else
+	  flag_reg_prefix_optional = 0;
+#endif
+#ifdef REGISTER_PREFIX
+	  init_regtable ();
+#endif
+	}
+      m68k_abspcadd = 0;
+      m68k_rel32 = 1;
+    }
+}
+
 /* Equal to MAX_PRECISION in atof-ieee.c */
 #define MAX_LITTLENUMS 6
 
@@ -6189,6 +6229,7 @@ md_parse_option (c, arg)
 
     case OPTION_REGISTER_PREFIX_OPTIONAL:
       flag_reg_prefix_optional = 1;
+      reg_prefix_optional_seen = 1;
       break;
 
       /* -V: SVR4 argument to print version ID.  */
diff --git a/gas/config/tc-m68k.h b/gas/config/tc-m68k.h
index 3f99de9..5602857 100644
--- a/gas/config/tc-m68k.h
+++ b/gas/config/tc-m68k.h
@@ -116,6 +116,9 @@ extern int m68k_aout_machtype;
 #define NO_PSEUDO_DOT
 #endif
 
+extern void m68k_mri_mode_change PARAMS ((int));
+#define MRI_MODE_CHANGE(i) m68k_mri_mode_change (i)
+
 #ifdef BFD_ASSEMBLER
 
 #define tc_frob_symbol(sym,punt) \