re PR tree-optimization/69802 (gcc ICE at -O1 and above on valid code on…

re PR tree-optimization/69802 (gcc ICE at -O1 and above  on valid code on x86_64-linux-gnu with “seg fault”)

	PR tree-optimization/69802
	* tree-ssa-reassoc.c (update_range_test): If op is
	SSA_NAME_IS_DEFAULT_DEF, give up unless tem is a positive
	op == 1 test of precision 1 integral op, otherwise handle
	that case as op itself.  Fix up formatting.
	(optimize_range_tests_to_bit_test, optimize_range_tests): Fix
	up formatting.

	* gcc.dg/pr69802.c: New test.

From-SVN: r233446

gcc/ChangeLog

+2016-02-16  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/69802
+	* tree-ssa-reassoc.c (update_range_test): If op is
+	SSA_NAME_IS_DEFAULT_DEF, give up unless tem is a positive
+	op == 1 test of precision 1 integral op, otherwise handle
+	that case as op itself.  Fix up formatting.
+	(optimize_range_tests_to_bit_test, optimize_range_tests): Fix
+	up formatting.
+
 2016-02-16  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/69586

gcc/testsuite/ChangeLog

+2016-02-16  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/69802
+	* gcc.dg/pr69802.c: New test.
+
 2016-02-16  Richard Biener  <rguenther@suse.de>
 
 	PR middle-end/69801

gcc/testsuite/gcc.dg/pr69802.c

+/* PR tree-optimization/69802 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -Wall" } */
+
+struct S { unsigned f : 1; };
+int a, d;
+
+int
+foo (void)
+{
+  unsigned b = 0;
+  struct S c;
+  d = ((1 && b) < c.f) & c.f;	/* { dg-warning "is used uninitialized" } */
+  return a;
+}
+
+int
+bar (_Bool c)
+{
+  unsigned b = 0;
+  d = ((1 && b) < c) & c;
+  return a;
+}

gcc/tree-ssa-reassoc.c

@@ -2046,19 +2046,41 @@ update_range_test (struct range_entry *range, struct range_entry *otherrange,
 {
   operand_entry *oe = (*ops)[range->idx];
   tree op = oe->op;
-  gimple *stmt = op ? SSA_NAME_DEF_STMT (op) :
-    last_stmt (BASIC_BLOCK_FOR_FN (cfun, oe->id));
+  gimple *stmt = op ? SSA_NAME_DEF_STMT (op)
+		    : last_stmt (BASIC_BLOCK_FOR_FN (cfun, oe->id));
   location_t loc = gimple_location (stmt);
   tree optype = op ? TREE_TYPE (op) : boolean_type_node;
   tree tem = build_range_check (loc, optype, unshare_expr (exp),
 				in_p, low, high);
   enum warn_strict_overflow_code wc = WARN_STRICT_OVERFLOW_COMPARISON;
   gimple_stmt_iterator gsi;
-  unsigned int i;
+  unsigned int i, uid;
 
   if (tem == NULL_TREE)
     return false;
 
+  /* If op is default def SSA_NAME, there is no place to insert the
+     new comparison.  Give up, unless we can use OP itself as the
+     range test.  */
+  if (op && SSA_NAME_IS_DEFAULT_DEF (op))
+    {
+      if (op == range->exp
+	  && ((TYPE_PRECISION (optype) == 1 && TYPE_UNSIGNED (optype))
+	      || TREE_CODE (optype) == BOOLEAN_TYPE)
+	  && (op == tem
+	      || (TREE_CODE (tem) == EQ_EXPR
+		  && TREE_OPERAND (tem, 0) == op
+		  && integer_onep (TREE_OPERAND (tem, 1))))
+	  && opcode != BIT_IOR_EXPR
+	  && (opcode != ERROR_MARK || oe->rank != BIT_IOR_EXPR))
+	{
+	  stmt = NULL;
+	  tem = op;
+	}
+      else
+	return false;
+    }
+
   if (strict_overflow_p && issue_strict_overflow_warning (wc))
     warning_at (loc, OPT_Wstrict_overflow,
 		"assuming signed overflow does not occur "
@@ -2096,12 +2118,22 @@ update_range_test (struct range_entry *range, struct range_entry *otherrange,
     tem = invert_truthvalue_loc (loc, tem);
 
   tem = fold_convert_loc (loc, optype, tem);
-  gsi = gsi_for_stmt (stmt);
-  unsigned int uid = gimple_uid (stmt);
+  if (stmt)
+    {
+      gsi = gsi_for_stmt (stmt);
+      uid = gimple_uid (stmt);
+    }
+  else
+    {
+      gsi = gsi_none ();
+      uid = 0;
+    }
+  if (stmt == NULL)
+    gcc_checking_assert (tem == op);
   /* In rare cases range->exp can be equal to lhs of stmt.
      In that case we have to insert after the stmt rather then before
      it.  If stmt is a PHI, insert it at the start of the basic block.  */
-  if (op != range->exp)
+  else if (op != range->exp)
     {
       gsi_insert_seq_before (&gsi, seq, GSI_SAME_STMT);
       tem = force_gimple_operand_gsi (&gsi, tem, true, NULL_TREE, true,
@@ -2489,7 +2521,7 @@ optimize_range_tests_to_bit_test (enum tree_code opcode, int first, int length,
 	  operand_entry *oe = (*ops)[ranges[i].idx];
 	  tree op = oe->op;
 	  gimple *stmt = op ? SSA_NAME_DEF_STMT (op)
-			   : last_stmt (BASIC_BLOCK_FOR_FN (cfun, oe->id));
+			    : last_stmt (BASIC_BLOCK_FOR_FN (cfun, oe->id));
 	  location_t loc = gimple_location (stmt);
 	  tree optype = op ? TREE_TYPE (op) : boolean_type_node;
 
@@ -2553,7 +2585,7 @@ optimize_range_tests_to_bit_test (enum tree_code opcode, int first, int length,
 	  gcc_assert (TREE_CODE (exp) == SSA_NAME);
 	  gimple_set_visited (SSA_NAME_DEF_STMT (exp), true);
 	  gimple *g = gimple_build_assign (make_ssa_name (optype),
-					  BIT_IOR_EXPR, tem, exp);
+					   BIT_IOR_EXPR, tem, exp);
 	  gimple_set_location (g, loc);
 	  gimple_seq_add_stmt_without_update (&seq, g);
 	  exp = gimple_assign_lhs (g);
@@ -2599,8 +2631,9 @@ optimize_range_tests (enum tree_code opcode,
       oe = (*ops)[i];
       ranges[i].idx = i;
       init_range_entry (ranges + i, oe->op,
-			oe->op ? NULL :
-			  last_stmt (BASIC_BLOCK_FOR_FN (cfun, oe->id)));
+			oe->op
+			? NULL
+			: last_stmt (BASIC_BLOCK_FOR_FN (cfun, oe->id)));
       /* For | invert it now, we will invert it again before emitting
 	 the optimized expression.  */
       if (opcode == BIT_IOR_EXPR