* config/tc-arm.c (create_register_alias): Return a boolean rather than an integer.

  Check the return value of insert_reg_alias and do not continue to create aliases once an insertion has failed.
  (s_unreq): Delete the all-upper-case and all-lower-case alternatives as well.
* testsuite/gas/arm/arm.s: Add tests for re-aliasing a previously removed alias.
* testsuite/gas/arm/arm.l: Add new expected warning message.

5 files changed, 98 insertions, 19 deletions

diff --git a/gas/ChangeLog b/gas/ChangeLog
index d1a43a3..602c58c 100644
--- a/gas/ChangeLog
+++ b/gas/ChangeLog
@@ -1,3 +1,12 @@
+2007-07-14  Nick Clifton  <nickc@redhat.com>
+
+	* config/tc-arm.c (create_register_alias): Return a boolean rather
+	than an integer.
+	Check the return value of insert_reg_alias and do not continue to
+	create aliases once an insertion has failed.
+	(s_unreq): Delete the all-upper-case and all-lower-case
+	alternatives as well.
+
 2007-07-12  Kai Tietz   <kai.tietz@onevision.com>
 
 	* symbols.c: Print bfd_hostptr_t to file via fprintf_vma.
diff --git a/gas/config/tc-arm.c b/gas/config/tc-arm.c
index fbb7ae2..82562d7 100644
--- a/gas/config/tc-arm.c
+++ b/gas/config/tc-arm.c
@@ -1971,7 +1971,7 @@ insert_reg_alias (char *str, int number, int type)
       else if (new->number != number || new->type != type)
 	as_warn (_("ignoring redefinition of register alias '%s'"), str);
 
-      return 0;
+      return NULL;
     }
 
   name = xstrdup (str);
@@ -2013,9 +2013,9 @@ insert_neon_reg_alias (char *str, int number, int type,
 	new_register_name .req existing_register_name
 
    If we find one, or if it looks sufficiently like one that we want to
-   handle any error here, return non-zero.  Otherwise return zero.  */
+   handle any error here, return TRUE.  Otherwise return FALSE.  */
 
-static int
+static bfd_boolean
 create_register_alias (char * newname, char *p)
 {
   struct reg_entry *old;
@@ -2026,17 +2026,17 @@ create_register_alias (char * newname, char *p)
      collapsed to single spaces.  */
   oldname = p;
   if (strncmp (oldname, " .req ", 6) != 0)
-    return 0;
+    return FALSE;
 
   oldname += 6;
   if (*oldname == '\0')
-    return 0;
+    return FALSE;
 
   old = hash_find (arm_reg_hsh, oldname);
   if (!old)
     {
       as_warn (_("unknown register '%s' -- .req ignored"), oldname);
-      return 1;
+      return TRUE;
     }
 
   /* If TC_CASE_SENSITIVE is defined, then newname already points to
@@ -2056,21 +2056,34 @@ create_register_alias (char * newname, char *p)
   /* Create aliases under the new name as stated; an all-lowercase
      version of the new name; and an all-uppercase version of the new
      name.  */
-  insert_reg_alias (nbuf, old->number, old->type);
-
-  for (p = nbuf; *p; p++)
-    *p = TOUPPER (*p);
+  if (insert_reg_alias (nbuf, old->number, old->type) != NULL)
+    {
+      for (p = nbuf; *p; p++)
+	*p = TOUPPER (*p);
 
-  if (strncmp (nbuf, newname, nlen))
-    insert_reg_alias (nbuf, old->number, old->type);
+      if (strncmp (nbuf, newname, nlen))
+	{
+	  /* If this attempt to create an additional alias fails, do not bother
+	     trying to create the all-lower case alias.  We will fail and issue
+	     a second, duplicate error message.  This situation arises when the
+	     programmer does something like:
+	       foo .req r0
+	       Foo .req r1
+	     The second .req creates the "Foo" alias but then fails to create
+	     the artifical FOO alias because it has already been created by the
+	     first .req.  */
+	  if (insert_reg_alias (nbuf, old->number, old->type) == NULL)
+	    return TRUE;
+	}
 
-  for (p = nbuf; *p; p++)
-    *p = TOLOWER (*p);
+      for (p = nbuf; *p; p++)
+	*p = TOLOWER (*p);
 
-  if (strncmp (nbuf, newname, nlen))
-    insert_reg_alias (nbuf, old->number, old->type);
+      if (strncmp (nbuf, newname, nlen))
+	insert_reg_alias (nbuf, old->number, old->type);
+    }
 
-  return 1;
+  return TRUE;
 }
 
 /* Create a Neon typed/indexed register alias using directives, e.g.:
@@ -2270,11 +2283,45 @@ s_unreq (int a ATTRIBUTE_UNUSED)
 		 name);
       else
 	{
+	  char * p;
+	  char * nbuf;
+
 	  hash_delete (arm_reg_hsh, name);
 	  free ((char *) reg->name);
           if (reg->neon)
             free (reg->neon);
 	  free (reg);
+
+	  /* Also locate the all upper case and all lower case versions.
+	     Do not complain if we cannot find one or the other as it
+	     was probably deleted above.  */
+	  
+	  nbuf = strdup (name);
+	  for (p = nbuf; *p; p++)
+	    *p = TOUPPER (*p);
+	  reg = hash_find (arm_reg_hsh, nbuf);
+	  if (reg)
+	    {
+	      hash_delete (arm_reg_hsh, nbuf);
+	      free ((char *) reg->name);
+	      if (reg->neon)
+		free (reg->neon);
+	      free (reg);
+	    }
+
+	  for (p = nbuf; *p; p++)
+	    *p = TOLOWER (*p);
+	  reg = hash_find (arm_reg_hsh, nbuf);
+	  if (reg)
+	    {
+	      hash_delete (arm_reg_hsh, nbuf);
+	      free ((char *) reg->name);
+	      if (reg->neon)
+		free (reg->neon);
+	      free (reg);
+	    }
+
+	  free (nbuf);
 	}
     }
 
diff --git a/gas/testsuite/ChangeLog b/gas/testsuite/ChangeLog
index b165e57..210e5f6 100644
--- a/gas/testsuite/ChangeLog
+++ b/gas/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2007-07-14  Nick Clifton  <nickc@redhat.com>
+
+	* gas/arm/arm.s: Add tests for re-aliasing a previously removed
+	alias.
+	* gas/arm/arm.l: Add new expected warning message.
+
 2007-07-04  H.J. Lu  <hongjiu.lu@intel.com>
 
 	* gas/i386/ssemmx2.d: Ignore padding.
diff --git a/gas/testsuite/gas/arm/req.l b/gas/testsuite/gas/arm/req.l
index 165d1d8..293db4d 100644
--- a/gas/testsuite/gas/arm/req.l
+++ b/gas/testsuite/gas/arm/req.l
@@ -1,3 +1,4 @@
 [^:]*: Assembler messages:
 [^:]*:18: Error: ARM register expected -- `add foo,foo,foo'
 [^:]*:21: Warning: ignoring attempt to undefine built-in register 'r0'
+[^:]*:41: Warning: ignoring redefinition of register alias 'FOO'
diff --git a/gas/testsuite/gas/arm/req.s b/gas/testsuite/gas/arm/req.s
index 341f66d..1330e75 100644
--- a/gas/testsuite/gas/arm/req.s
+++ b/gas/testsuite/gas/arm/req.s
@@ -19,7 +19,23 @@ test_dot_req_and_unreq:
 
 	# Attempt to remove the builtin alias for r0.
         .unreq r0
-
+	
 	# That is ignored, so this should still work.
 	add r0, r0, r0
-	
+
+	# Now attempt to re-alias foo.  There used to be a bug whereby the
+	# first creation of an alias called foo would also create an alias
+	# called FOO, but the .unreq of foo would not delete FOO.  Thus a
+	# second attempt at aliasing foo (to something different than
+	# before) would fail because the assembler would complain that FOO
+	# already existed.
+	foo .req r1
+
+	add foo, foo, foo
+
+	# Check that the upper case alias was also recreated.
+	add FOO, FOO, FOO
+
+	# Check that a second attempt to alias foo, using a mixed case
+	# verison of the name, will fail.
+	Foo .req r2