re PR tree-optimization/46969 (-fcompare-debug failure with -O -ftree-vectorize -ftree-parallelize-loops=2)

PR tree-optimization/46969
	* tree-parloops.c (struct reduction_info): Add reduc_version.
	(reduction_info_hash): Return reduc_version field.
	(reduction_phi): Set reduc_version to gimple_uid (phi).
	(build_new_reduction): Set reduc_version to SSA_NAME_VERSION of
	phi result.
	(set_reduc_phi_uids): New function.
	(gather_scalar_reductions): Call it at the end through htab_traverse.

	* gcc.dg/autopar/pr46969.c: New test.

From-SVN: r168034

gcc/ChangeLog

@@ -1,3 +1,14 @@
+2010-12-18  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/46969
+	* tree-parloops.c (struct reduction_info): Add reduc_version.
+	(reduction_info_hash): Return reduc_version field.
+	(reduction_phi): Set reduc_version to gimple_uid (phi).
+	(build_new_reduction): Set reduc_version to SSA_NAME_VERSION of
+	phi result.
+	(set_reduc_phi_uids): New function.
+	(gather_scalar_reductions): Call it at the end through htab_traverse.
+
 2010-12-18  Nicola Pero  <nicola.pero@meta-innovation.com>
 
 	* c-parser.c (c_parser_objc_try_catch_finally_statement): Call

gcc/testsuite/ChangeLog

@@ -1,3 +1,8 @@
+2010-12-18  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/46969
+	* gcc.dg/autopar/pr46969.c: New test.
+
 2010-12-18  Nicola Pero  <nicola.pero@meta-innovation.com>
 
 	* objc.dg/fobjc-exceptions-1.m: Updated.

gcc/testsuite/gcc.dg/autopar/pr46969.c

@@ -0,0 +1,31 @@
+/* PR tree-optimization/46969 */
+/* { dg-do compile } */
+/* { dg-options "-O3 -ftree-parallelize-loops=2 -fcompare-debug" } */
+
+extern void abort (void);
+#define F(name) \
+int								\
+name (unsigned char *x)						\
+{								\
+  int i;							\
+  unsigned int c, d, e;						\
+  if (x != 0)							\
+    {								\
+      for (i = 0, d = 0, e = 0xFFFFFFFF;			\
+	   i < 64;						\
+	   i += (int) sizeof(unsigned int))			\
+        {							\
+          c = *((unsigned int *)(&x[i]));			\
+          d = d | c;						\
+          e = e & c;						\
+        }							\
+      if (!((d == e) && ((d >> 8) == (e & 0x00FFFFFF))))	\
+        abort ();						\
+    }								\
+  return 0;							\
+}
+F (foo0) F (foo1)
+F (foo2) F (foo3)
+F (foo4) F (foo5)
+F (foo6) F (foo7)
+F (foo8) F (foo9)

gcc/tree-parloops.c

@@ -168,6 +168,8 @@ struct reduction_info
   gimple reduc_stmt;		/* reduction statement.  */
   gimple reduc_phi;		/* The phi node defining the reduction.  */
   enum tree_code reduction_code;/* code for the reduction operation.  */
+  unsigned reduc_version;	/* SSA_NAME_VERSION of original reduc_phi
+				   result.  */
   gimple keep_res;		/* The PHI_RESULT of this phi is the resulting value
 				   of the reduction variable when existing the loop. */
   tree initial_value;		/* The initial value of the reduction var before entering the loop.  */
@@ -195,7 +197,7 @@ reduction_info_hash (const void *aa)
 {
   const struct reduction_info *a = (const struct reduction_info *) aa;
 
-  return htab_hash_pointer (a->reduc_phi);
+  return a->reduc_version;
 }
 
 static struct reduction_info *
@@ -207,6 +209,7 @@ reduction_phi (htab_t reduction_list, gimple phi)
     return NULL;
 
   tmpred.reduc_phi = phi;
+  tmpred.reduc_version = gimple_uid (phi);
   red = (struct reduction_info *) htab_find (reduction_list, &tmpred);
 
   return red;
@@ -1774,11 +1777,22 @@ build_new_reduction (htab_t reduction_list, gimple reduc_stmt, gimple phi)
 
   new_reduction->reduc_stmt = reduc_stmt;
   new_reduction->reduc_phi = phi;
+  new_reduction->reduc_version = SSA_NAME_VERSION (gimple_phi_result (phi));
   new_reduction->reduction_code = gimple_assign_rhs_code (reduc_stmt);
   slot = htab_find_slot (reduction_list, new_reduction, INSERT);
   *slot = new_reduction;
 }
 
+/* Callback for htab_traverse.  Sets gimple_uid of reduc_phi stmts.  */
+
+static int
+set_reduc_phi_uids (void **slot, void *data ATTRIBUTE_UNUSED)
+{
+  struct reduction_info *const red = (struct reduction_info *) *slot;
+  gimple_set_uid (red->reduc_phi, red->reduc_version);
+  return 1;
+}
+
 /* Detect all reductions in the LOOP, insert them into REDUCTION_LIST.  */
 
 static void
@@ -1810,7 +1824,12 @@ gather_scalar_reductions (loop_p loop, htab_t reduction_list)
               build_new_reduction (reduction_list, reduc_stmt, phi);
         }
     }
-    destroy_loop_vec_info (simple_loop_info, true);
+  destroy_loop_vec_info (simple_loop_info, true);
+
+  /* As gimple_uid is used by the vectorizer in between vect_analyze_loop_form
+     and destroy_loop_vec_info, we can set gimple_uid of reduc_phi stmts
+     only now.  */
+  htab_traverse (reduction_list, set_reduc_phi_uids, NULL);
 }
 
 /* Try to initialize NITER for code generation part.  */