[PATCH] Fix PPC32 local checks in 3.2 (was: Re: [libffi] closures for sparc)

[Franz Sirl]

On Tuesday 21 January 2003 00:01, Jakub Jelinek wrote:
> On Sun, Jan 05, 2003 at 11:26:30AM -0500, Jeff Sturm wrote:
> > On Sat, 4 Jan 2003, Andreas Tobler wrote:
> > > Hm, powerpc-unknown-linux-gnu doesn't like the static:
> > >
> > > .libs/ffitest.o: could not read symbols: Bad value
> >
> > Strange.  Surely this isn't a problem in libffi though?
> >
> > Can you try a newer ld and see if it fixes the problem?  If not, let me
> > know and I'll attempt a cross build (I don't have a powerpc-linux machine
> > handy).
>
> I get the same on ppc-linux. To me this looks like a bug in gcc:
>
> /* { dg-do link } */
> /* { dg-options "-O2 -fpic" } */
> static char foo [128];
> void bar (void)
> {
>   ((void (*)(void))foo)();
> }
> int main ()
> {
> }
>
> results in:
> ...
>         bl foo@plt
> ...
>         .lcomm  foo,128,4
>
> Note @plt used for local symbol.

Yeah, I have a patch for that. I simply backported the gllobal gcc-3.3 
binds_local_p routine to a local one in rs6000.c. Works like a charm here, no 
regressions and it works for glibc, qt, KDE-3.1, kernel just fine.

OK to commit to gcc-3_2-branch?

Jakub, as soon as you pull this over to the rhl8 branch, you can remove the 
"ExcludeArch: ppc" of the Omni package in RawHide.

Franz.

	* config/rs6000/rs6000.c (rs6000_binds_local_p): New functiion.
	(rs6000_encode_section_info): Use it.

-------------- next part --------------
Index: gcc/config/rs6000/rs6000.c
===================================================================
RCS file: /cvsroot/gcc/gcc/gcc/config/rs6000/rs6000.c,v
retrieving revision 1.291.2.13.2.5.2.4
diff -u -p -r1.291.2.13.2.5.2.4 rs6000.c
--- gcc/config/rs6000/rs6000.c	8 Dec 2002 19:39:16 -0000	1.291.2.13.2.5.2.4
+++ gcc/config/rs6000/rs6000.c	20 Jan 2003 23:23:41 -0000
@@ -155,6 +155,7 @@ static void rs6000_elf_asm_out_destructo
 #ifdef OBJECT_FORMAT_COFF
 static void xcoff_asm_named_section PARAMS ((const char *, unsigned int));
 #endif
+static bool rs6000_binds_local_p PARAMS ((tree));
 static int rs6000_adjust_cost PARAMS ((rtx, rtx, rtx, int));
 static int rs6000_adjust_priority PARAMS ((rtx, int));
 static int rs6000_issue_rate PARAMS ((void));
@@ -10947,7 +10948,50 @@ rs6000_unique_section (decl, reloc)
   DECL_SECTION_NAME (decl) = build_string (len, string);
 }
 
-
+
+static bool
+rs6000_binds_local_p (exp)
+     tree exp;
+{
+  bool local_p;
+  tree attr;
+
+  /* A non-decl is an entry in the constant pool.  */
+  if (!DECL_P (exp))
+    local_p = true;
+  /* Static variables are always local.  */
+  else if (! TREE_PUBLIC (exp))
+    local_p = true;
+  /* A variable is local if the user tells us so.  */
+  else if ((attr = lookup_attribute ("visibility", DECL_ATTRIBUTES (exp)))
+	   && strcmp (TREE_STRING_POINTER (TREE_VALUE (TREE_VALUE (attr))),
+		      "default") != 0)
+    local_p = true;
+  /* Otherwise, variables defined outside this object may not be local.  */
+  else if (DECL_EXTERNAL (exp))
+    local_p = false;
+  /* Linkonce and weak data are never local.  */
+  else if (DECL_ONE_ONLY (exp) || DECL_WEAK (exp))
+    local_p = false;
+  /* If PIC, then assume that any global name can be overridden by
+   *      symbols resolved from other modules.  */
+  else if (flag_pic || rs6000_flag_pic)
+    local_p = false;
+  /* Uninitialized COMMON variable may be unified with symbols
+   *      resolved from other modules.  */
+  else if (DECL_COMMON (exp)
+	   && (DECL_INITIAL (exp) == NULL
+	       || DECL_INITIAL (exp) == error_mark_node))
+    local_p = false;
+  /* Otherwise we're left with initialized (or non-common) global data
+   *      which is of necessity defined locally.  */
+  else
+    local_p = true;
+
+  return local_p;
+}
+
+
 /* If we are referencing a function that is static or is known to be
    in this file, make the SYMBOL_REF special.  We can use this to indicate
    that we can branch to this function without emitting a no-op after the
@@ -10963,12 +11007,7 @@ rs6000_encode_section_info (decl)
   if (TREE_CODE (decl) == FUNCTION_DECL)
     {
       rtx sym_ref = XEXP (DECL_RTL (decl), 0);
-      if (!TREE_PUBLIC (decl)
-	  || (!DECL_EXTERNAL (decl)
-	      && !DECL_ONE_ONLY (decl)
-	      && !DECL_WEAK (decl)
-	      && !flag_pic
-	      && !rs6000_flag_pic))
+      if (rs6000_binds_local_p (decl))
 	SYMBOL_REF_FLAG (sym_ref) = 1;
 
       if (DEFAULT_ABI == ABI_AIX)
@@ -10987,10 +11026,14 @@ rs6000_encode_section_info (decl)
 	   && DEFAULT_ABI == ABI_V4
 	   && TREE_CODE (decl) == VAR_DECL)
     {
+      rtx sym_ref = XEXP (DECL_RTL (decl), 0);
       int size = int_size_in_bytes (TREE_TYPE (decl));
       tree section_name = DECL_SECTION_NAME (decl);
       const char *name = (char *)0;
       int len = 0;
+
+      if (rs6000_binds_local_p (decl))
+	SYMBOL_REF_FLAG (sym_ref) = 1;
 
       if (section_name)
 	{