re PR middle-end/17982 (stop calling assemble_external before final assembly output time)

PR 17982
	* varasm.c (pending_assemble_externals): New static.
	(assemble_external_real): Meat of assemble_external split out
	to this new function.
	(process_pending_assemble_externals): New function.
	(assemble_external): Use gcc_assert.  If flag_unit_at_a_time
	is true and the basic test passes, merely cons the decl onto
	the pending list to be handled later.
	* tree.h: Declare process_pending_assemble_externals.
	* cgraphunit.c (cgraph_optimize): Call it.

	* config/h8300/h8300.h: Do not define ASM_OUTPUT_EXTERNAL.

From-SVN: r91914

gcc/ChangeLog

@@ -1,3 +1,18 @@
+2004-12-08  Zack Weinberg  <zack@codesourcery.com>
+
+	PR 17982
+	* varasm.c (pending_assemble_externals): New static.
+	(assemble_external_real): Meat of assemble_external split out
+	to this new function.
+	(process_pending_assemble_externals): New function.
+	(assemble_external): Use gcc_assert.  If flag_unit_at_a_time
+	is true and the basic test passes, merely cons the decl onto
+	the pending list to be handled later.
+	* tree.h: Declare process_pending_assemble_externals.
+	* cgraphunit.c (cgraph_optimize): Call it.
+
+	* config/h8300/h8300.h: Do not define ASM_OUTPUT_EXTERNAL.
+
 2004-12-08  Kazu Hirata  <kazu@cs.umass.edu>
 
 	* cfgloopmanip.c (create_preheader): Speed up by "unrolling"

gcc/cgraphunit.c

@@ -1750,6 +1750,9 @@ cgraph_optimize (void)
 #endif
   if (!flag_unit_at_a_time)
     return;
+
+  process_pending_assemble_externals ();
+
   timevar_push (TV_CGRAPHOPT);
   if (!quiet_flag)
     fprintf (stderr, "Performing intraprocedural optimizations\n");

gcc/config/h8300/h8300.h

@@ -1160,8 +1160,6 @@ struct cum_arg
 { {"er0", 0}, {"er1", 1}, {"er2", 2}, {"er3", 3}, {"er4", 4}, \
   {"er5", 5}, {"er6", 6}, {"er7", 7}, {"r7", 7} }
 
-#define ASM_OUTPUT_EXTERNAL(FILE, DECL, NAME)
-
 /* Globalizing directive for a label.  */
 #define GLOBAL_ASM_OP "\t.global "
 

gcc/tree.h

@@ -3701,6 +3701,7 @@ extern void mark_referenced (tree);
 extern void mark_decl_referenced (tree);
 extern void notice_global_symbol (tree);
 extern void set_user_assembler_name (tree, const char *);
+extern void process_pending_assemble_externals (void);
 
 /* In stmt.c */
 extern void expand_computed_goto (tree);

gcc/varasm.c

@@ -1759,6 +1759,12 @@ contains_pointers_p (tree type)
     }
 }
 
+/* In unit-at-a-time mode, we delay assemble_external processing until
+   the compilation unit is finalized.  This is the best we can do for
+   right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
+   it all the way to final.  See PR 17982 for further discussion.  */
+static GTY(()) tree pending_assemble_externals;
+
 #ifdef ASM_OUTPUT_EXTERNAL
 /* True if DECL is a function decl for which no out-of-line copy exists.
    It is assumed that DECL's assembler name has been set.  */
@@ -1780,24 +1786,11 @@ incorporeal_function_p (tree decl)
     }
   return false;
 }
-#endif
 
-/* Output something to declare an external symbol to the assembler.
-   (Most assemblers don't need this, so we normally output nothing.)
-   Do nothing if DECL is not external.  */
-
-void
-assemble_external (tree decl ATTRIBUTE_UNUSED)
-{
-  /* Because most platforms do not define ASM_OUTPUT_EXTERNAL, the
-     main body of this code is only rarely exercised.  To provide some
-     testing, on all platforms, we make sure that the ASM_OUT_FILE is
-     open.  If it's not, we should not be calling this function.  */
-  if (!asm_out_file)
-    abort ();
-
-#ifdef ASM_OUTPUT_EXTERNAL
-  if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
+/* Actually do the tests to determine if this is necessary, and invoke
+   ASM_OUTPUT_EXTERNAL.  */
+static void
+assemble_external_real (tree decl)
 {
   rtx rtl = DECL_RTL (decl);
 
@@ -1811,6 +1804,42 @@ assemble_external (tree decl ATTRIBUTE_UNUSED)
     }
 }
 #endif
+
+void
+process_pending_assemble_externals (void)
+{
+#ifdef ASM_OUTPUT_EXTERNAL
+  tree list;
+  for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
+    assemble_external_real (TREE_VALUE (list));
+
+  pending_assemble_externals = 0;
+#endif
+}
+
+/* Output something to declare an external symbol to the assembler.
+   (Most assemblers don't need this, so we normally output nothing.)
+   Do nothing if DECL is not external.  */
+
+void
+assemble_external (tree decl ATTRIBUTE_UNUSED)
+{
+  /* Because most platforms do not define ASM_OUTPUT_EXTERNAL, the
+     main body of this code is only rarely exercised.  To provide some
+     testing, on all platforms, we make sure that the ASM_OUT_FILE is
+     open.  If it's not, we should not be calling this function.  */
+  gcc_assert (asm_out_file);
+
+#ifdef ASM_OUTPUT_EXTERNAL
+  if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
+    return;
+
+  if (flag_unit_at_a_time)
+    pending_assemble_externals = tree_cons (0, decl,
+					    pending_assemble_externals);
+  else
+    assemble_external_real (decl);
+#endif
 }
 
 /* Similar, for calling a library function FUN.  */