Fix for PR 3128, IA-64 linux kernel miscompile

Fix for PR 3128, IA-64 linux kernel miscompile
	* loop.c (strength_reduce): Move bl->all_reduced set before
	check_ext_dependant_givs call.
	(check_ext_dependant_givs): Clear bl->all_reduced when ignoring givs.

From-SVN: r43298

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 91162d51ee99a6392a26aa8935e09100878f02ac..a6f3f681024191ea0c9a78f9471c72e39d7e0638 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2001-06-12  Jim Wilson  <wilson@redhat.com>
+
+       * loop.c (strength_reduce): Move bl->all_reduced set before
+       check_ext_dependant_givs call.
+       (check_ext_dependant_givs): Clear bl->all_reduced when ignoring givs.
+
 2001-06-12  Alexandre Oliva  <aoliva@redhat.com>
 
        * doc/extend.texi (Function Attributes): Document SH's sp_switch

diff --git a/gcc/loop.c b/gcc/loop.c
index fac9a840bc8deeddc361068fb6432a0068b3e06c..ec8dc0ac261f9204fe63c1b6a1be072dff72c6fc 100644 (file)
--- a/gcc/loop.c
+++ b/gcc/loop.c
@@ -4306,6 +4306,11 @@ strength_reduce (loop, flags)
         provided all givs are reduced.  */
       bl->eliminable = loop_biv_eliminable_p (loop, bl, threshold, insn_count);
 
+      /* This will be true at the end, if all givs which depend on this
+        biv have been strength reduced.
+        We can't (currently) eliminate the biv unless this is so.  */
+      bl->all_reduced = 1;
+
       /* Check each extension dependent giv in this class to see if its
         root biv is safe from wrapping in the interior mode.  */
       check_ext_dependant_givs (bl, loop_info);
@@ -4313,11 +4318,6 @@ strength_reduce (loop, flags)
       /* Combine all giv's for this iv_class.  */
       combine_givs (regs, bl);
 
-      /* This will be true at the end, if all givs which depend on this
-        biv have been strength reduced.
-        We can't (currently) eliminate the biv unless this is so.  */
-      bl->all_reduced = 1;
-
       for (v = bl->giv; v; v = v->next_iv)
        {
          struct induction *tv;
@@ -6660,6 +6660,7 @@ check_ext_dependant_givs (bl, loop_info)
                         INSN_UID (v->insn), why);
              }
            v->ignore = 1;
+           bl->all_reduced = 0;
          }
       }
 }