re PR target/28574 (switch statement points to unreferenced label at -O2)

	PR target/28574
	* ifcvt.c (dead_or_predicable): Don't predicate then blocks
	with tablejumps in them.

From-SVN: r117084

gcc/ChangeLog

+2006-09-20  Steve Ellcey  <sje@cup.hp.com>
+
+	PR target/28574
+	* ifcvt.c (dead_or_predicable): Don't predicate then blocks
+	with tablejumps in them.
+
 2006-09-20  Jakub Jelinek  <jakub@redhat.com>
 
 	PR middle-end/28046

gcc/ifcvt.c

@@ -3560,6 +3560,13 @@ dead_or_predicable (basic_block test_bb, basic_block merge_bb,
   head = BB_HEAD (merge_bb);
   end = BB_END (merge_bb);
 
+  /* If merge_bb ends with a tablejump, predicating/moving insn's
+     into test_bb and then deleting merge_bb will result in the jumptable
+     that follows merge_bb being removed along with merge_bb and then we
+     get an unresolved reference to the jumptable.  */
+  if (tablejump_p (end, NULL, NULL))
+    return FALSE;
+
   if (LABEL_P (head))
     head = NEXT_INSN (head);
   if (NOTE_P (head))

gcc/testsuite/gcc.dg/pr28574.c

+/* On IA64 This test resulted in a missing jumptable and an undefined
+   reference    to a label.  Make sure we can compile and link it with
+   no undefs at -O2.  */
+
+/* { dg-do link } */
+/* { dg-options "-O2" } */
+
+typedef enum yasm_module_type {
+    YASM_MODULE_ARCH = 0,
+    YASM_MODULE_DBGFMT,
+    YASM_MODULE_OBJFMT,
+    YASM_MODULE_LISTFMT,
+    YASM_MODULE_OPTIMIZER
+} yasm_module_type;
+
+struct yasm_module {
+    const char *name;
+};
+
+typedef struct yasm_module yasm_arch_module;
+typedef struct yasm_module yasm_dbgfmt_module;
+typedef struct yasm_module yasm_objfmt_module;
+typedef struct yasm_module yasm_listfmt_module;
+typedef struct yasm_module yasm_optimizer_module;
+
+typedef struct module {
+    void *data;
+} module;
+
+static struct {
+    module *m;
+    int n;
+} module_types[] = {
+ {},
+};
+
+void
+yasm_list_modules(yasm_module_type type,
+                  void (*printfunc) (const char *name))
+{
+    int i;
+    module *modules = module_types[type].m;
+    yasm_arch_module *arch;
+    yasm_dbgfmt_module *dbgfmt;
+    yasm_objfmt_module *objfmt;
+    yasm_listfmt_module *listfmt;
+    yasm_optimizer_module *optimizer;
+
+    for (i=0; i<2; i++) {
+        switch (type) {
+            case YASM_MODULE_ARCH:
+                arch = modules[i].data;
+                printfunc(arch->name);
+                break;
+            case YASM_MODULE_DBGFMT:
+                dbgfmt = modules[i].data;
+                printfunc(dbgfmt->name);
+                break;
+            case YASM_MODULE_OBJFMT:
+                objfmt = modules[i].data;
+                printfunc(objfmt->name);
+                break;
+            case YASM_MODULE_LISTFMT:
+                listfmt = modules[i].data;
+                printfunc(listfmt->name);
+                break;
+            case YASM_MODULE_OPTIMIZER:
+                optimizer = modules[i].data;
+                printfunc(optimizer->name);
+        }
+    }
+}
+
+main() {}