[Bug tree-optimization/30858] [4.3 Regression] ice for legal code with -O2 -ftree-vectorize

["dorit at il dot ibm dot com" <gcc-bugzilla@gcc.gnu.org>]

------- Comment #5 from dorit at il dot ibm dot com  2007-02-19 14:12 -------
Looks like I wasn't careful enough with my fix for PR30771. Here is a fix for
that fix I'm now testing:

Index: tree-vect-analyze.c
===================================================================
--- tree-vect-analyze.c (revision 122128)
+++ tree-vect-analyze.c (working copy)
@@ -124,10 +124,11 @@

          /* Two cases of "relevant" phis: those that define an
             induction that is used in the loop, and those that
-            define a reduction.  */
+            directly define a reduction.  */
          if ((STMT_VINFO_RELEVANT (stmt_info) == vect_used_in_loop
               && STMT_VINFO_DEF_TYPE (stmt_info) == vect_induction_def)
-             || (STMT_VINFO_RELEVANT (stmt_info) == vect_used_by_reduction
+             || (STMT_VINFO_RELEVANT (stmt_info) ==
+                                          vect_used_directly_by_reduction
                  && STMT_VINFO_DEF_TYPE (stmt_info) == vect_reduction_def))
             {
              gcc_assert (!STMT_VINFO_VECTYPE (stmt_info));
@@ -328,8 +329,12 @@
            return false;
          }

-         if (STMT_VINFO_RELEVANT (stmt_info) == vect_used_in_loop
-             && STMT_VINFO_DEF_TYPE (stmt_info) != vect_induction_def)
+         if ((STMT_VINFO_RELEVANT (stmt_info) == vect_used_in_loop
+              && STMT_VINFO_DEF_TYPE (stmt_info) != vect_induction_def)
+             || (STMT_VINFO_RELEVANT (stmt_info) >
+                                           vect_used_directly_by_reduction
+                  && STMT_VINFO_DEF_TYPE (stmt_info) == vect_reduction_def))
+
            {
              /* Most likely a reduction-like computation that is used
                 in the loop.  */
@@ -2313,9 +2318,11 @@
       if (STMT_VINFO_DEF_TYPE (stmt_vinfo) == vect_reduction_def)
        {
          gcc_assert (relevant == vect_unused_in_loop && live_p);
-         relevant = vect_used_by_reduction;
+         relevant = vect_used_directly_by_reduction;
          live_p = false;
        }
+      else if (relevant == vect_used_directly_by_reduction)
+       relevant = vect_used_by_reduction;

       i = 0;
       FOR_EACH_SSA_TREE_OPERAND (use, stmt, iter, SSA_OP_USE)
Index: tree-vectorizer.h
===================================================================
--- tree-vectorizer.h   (revision 122128)
+++ tree-vectorizer.h   (working copy)
@@ -175,6 +175,7 @@
 /* Indicates whether/how a variable is used in the loop.  */
 enum vect_relevant {
   vect_unused_in_loop = 0,
+  vect_used_directly_by_reduction,
   vect_used_by_reduction,
   vect_used_in_loop
 };


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30858