gas: add visibility support using GNU syntax on XCOFF

In order to ease port of GNU assembly code and especially ld testsuite,
this patch allows XCOFF to accept the usual GNU syntax for visibility.

PR 22085

gas/ChangeLog:

	* config/tc-ppc.c (ppc_GNU_visibility): New function.
	* testsuite/gas/ppc/aix.exp: Add new tests.
	* testsuite/gas/ppc/xcoff-visibility-2-32.d: New test.
	* testsuite/gas/ppc/xcoff-visibility-2-64.d: New test.
	* testsuite/gas/ppc/xcoff-visibility-2.s: New test.

gas/config/tc-ppc.c

@@ -121,6 +121,7 @@ static void ppc_toc (int);
 static void ppc_xcoff_cons (int);
 static void ppc_vbyte (int);
 static void ppc_weak (int);
+static void ppc_GNU_visibility (int);
 #endif
 
 #ifdef OBJ_ELF
@@ -246,6 +247,11 @@ const pseudo_typeS md_pseudo_table[] =
   { "short",	ppc_xcoff_cons,	1 },
   { "vbyte",    ppc_vbyte,	0 },
   { "weak",     ppc_weak,	0 },
+
+  /* Enable GNU syntax for symbol visibility.  */
+  {"internal",  ppc_GNU_visibility, SYM_V_INTERNAL},
+  {"hidden",    ppc_GNU_visibility, SYM_V_HIDDEN},
+  {"protected", ppc_GNU_visibility, SYM_V_PROTECTED},
 #endif
 
 #ifdef OBJ_ELF
@@ -4321,6 +4327,38 @@ ppc_xcoff_get_visibility (void) {
   return 0;
 }
 
+/* Retrieve visiblity using GNU syntax.  */
+static void ppc_GNU_visibility (int visibility) {
+  int c;
+  char *name;
+  symbolS *symbolP;
+  coff_symbol_type *coffsym;
+
+  do
+    {
+      if ((name = read_symbol_name ()) == NULL)
+	break;
+      symbolP = symbol_find_or_make (name);
+      coffsym = coffsymbol (symbol_get_bfdsym (symbolP));
+
+      coffsym->native->u.syment.n_type &= ~SYM_V_MASK;
+      coffsym->native->u.syment.n_type |= visibility;
+
+      c = *input_line_pointer;
+      if (c == ',')
+	{
+	  input_line_pointer ++;
+
+	  SKIP_WHITESPACE ();
+
+	  if (*input_line_pointer == '\n')
+	    c = '\n';
+	}
+    }
+  while (c == ',');
+
+  demand_empty_rest_of_line ();
+}
 
 /* The .comm and .lcomm pseudo-ops for XCOFF.  XCOFF puts common
    symbols in the .bss segment as though they were local common

gas/testsuite/gas/ppc/aix.exp

@@ -90,4 +90,6 @@ if { [istarget "powerpc*-*-aix*"] || [istarget "rs6000-*-aix*"] } then {
 
     run_dump_test "xcoff-visibility-1-32"
     run_dump_test "xcoff-visibility-1-64"
+    run_dump_test "xcoff-visibility-2-32"
+    run_dump_test "xcoff-visibility-2-64"
 }

gas/testsuite/gas/ppc/xcoff-visibility-2-32.d

@@ -0,0 +1,18 @@
+#as: -a32
+#source: xcoff-visibility-2.s
+#objdump: -t
+#name: XCOFF Visibility 2 (32 bit)
+
+.*
+
+SYMBOL TABLE:
+.*
+.*
+\[  2\].*\(ty 1000\).*internal
+.*
+\[  4\].*\(ty 2000\).*hidden
+.*
+\[  6\].*\(ty 3000\).*protected
+.*
+\[  8\].*\(ty 1000\).*dual
+.*

gas/testsuite/gas/ppc/xcoff-visibility-2-64.d

@@ -0,0 +1,18 @@
+#as: -a64
+#source: xcoff-visibility-2.s
+#objdump: -t
+#name: XCOFF Visibility 2 (64 bit)
+
+.*
+
+SYMBOL TABLE:
+.*
+.*
+\[  2\].*\(ty 1000\).*internal
+.*
+\[  4\].*\(ty 2000\).*hidden
+.*
+\[  6\].*\(ty 3000\).*protected
+.*
+\[  8\].*\(ty 1000\).*dual
+.*

gas/testsuite/gas/ppc/xcoff-visibility-2.s

@@ -0,0 +1,9 @@
+# Ensure that GNU syntax is accepted even for XCOFF.
+  .internal internal
+  .hidden hidden
+  .protected protected
+
+# Ensure that only the last visibility is taken into
+# account, when several are provided.
+  .protected dual
+  .internal dual