* config/tc-avr.c: Add specified_mcu variable for selected mcu.

	(enum options): add OPTION_RMW_ISA for -mrmw option.
	(struct option md_longopts): Add mrmw option.
	(md_show_usage): add -mrmw option description.
	(md_parse_option): Update isa details if -mrmw option specified.
	* doc/c-avr.texi: Add doc for new option -mrmw.
	* gas/avr/avr.exp: Run new tests.
	* gas/avr/rmw.d: Add test for additional ISA support.
	* gas/avr/rmw.s: Ditto.

1 files changed, 17 insertions, 3 deletions

diff --git a/gas/config/tc-avr.c b/gas/config/tc-avr.c
index d382fd9..5049d11 100644
--- a/gas/config/tc-avr.c
+++ b/gas/config/tc-avr.c
@@ -326,8 +326,10 @@ static struct mcu_type_s mcu_types[] =
   {NULL, 0, 0}
 };
 
+
 /* Current MCU type.  */
 static struct mcu_type_s   default_mcu = {"avr2", AVR_ISA_AVR2, bfd_mach_avr2};
+static struct mcu_type_s   specified_mcu;
 static struct mcu_type_s * avr_mcu = & default_mcu;
 
 /* AVR target-specific switches.  */
@@ -398,7 +400,8 @@ enum options
 {
   OPTION_ALL_OPCODES = OPTION_MD_BASE + 1,
   OPTION_NO_SKIP_BUG,
-  OPTION_NO_WRAP
+  OPTION_NO_WRAP,
+  OPTION_ISA_RMW
 };
 
 struct option md_longopts[] =
@@ -407,6 +410,7 @@ struct option md_longopts[] =
   { "mall-opcodes", no_argument, NULL, OPTION_ALL_OPCODES },
   { "mno-skip-bug", no_argument, NULL, OPTION_NO_SKIP_BUG },
   { "mno-wrap",     no_argument, NULL, OPTION_NO_WRAP     },
+  { "mrmw",         no_argument, NULL, OPTION_ISA_RMW     },
   { NULL, no_argument, NULL, 0 }
 };
 
@@ -511,7 +515,9 @@ md_show_usage (FILE *stream)
 	"  -mno-skip-bug    disable warnings for skipping two-word instructions\n"
 	"                   (default for avr4, avr5)\n"
 	"  -mno-wrap        reject rjmp/rcall instructions with 8K wrap-around\n"
-	"                   (default for avr3, avr5)\n"));
+	"                   (default for avr3, avr5)\n"
+	"  -mrmw            accept Read-Modify-Write instructions\n"
+    ));
   show_mcu_list (stream);
 }
 
@@ -558,7 +564,12 @@ md_parse_option (int c, char *arg)
 	   type - this for allows passing -mmcu=... via gcc ASM_SPEC as well
 	   as .arch ... in the asm output at the same time.  */
 	if (avr_mcu == &default_mcu || avr_mcu->mach == mcu_types[i].mach)
-	  avr_mcu = &mcu_types[i];
+      {
+        specified_mcu.name = mcu_types[i].name;
+        specified_mcu.isa  |= mcu_types[i].isa;
+        specified_mcu.mach = mcu_types[i].mach;
+        avr_mcu = &specified_mcu;
+      }
 	else
 	  as_fatal (_("redefinition of mcu type `%s' to `%s'"),
 		    avr_mcu->name, mcu_types[i].name);
@@ -573,6 +584,9 @@ md_parse_option (int c, char *arg)
     case OPTION_NO_WRAP:
       avr_opt.no_wrap = 1;
       return 1;
+    case OPTION_ISA_RMW:
+      specified_mcu.isa |= AVR_ISA_RMW;
+      return 1;
     }
 
   return 0;