Index: gcc-head/gcc/tree-vrp.c
===================================================================
--- gcc-head.orig/gcc/tree-vrp.c
+++ gcc-head/gcc/tree-vrp.c
@@ -6747,19 +6746,92 @@ varying:
   return SSA_PROP_VARYING;
 }

+/* Returns operand1 of ssa-name with SSA_NAME as code, Otherwise it
+   returns NULL_TREE.  */
+static tree
+ssa_name_get_inner_ssa_name_p (tree op)
+{
+  gimple stmt;
+
+  if (TREE_CODE (op) != SSA_NAME
+      || !is_gimple_assign (SSA_NAME_DEF_STMT (op)))
+    return NULL_TREE;
+  stmt = SSA_NAME_DEF_STMT (op);
+  if (gimple_assign_rhs_code (stmt) != SSA_NAME)
+    return NULL_TREE;
+  return gimple_assign_rhs1 (stmt);
+}
+
+/* Returns operand of cast operation, if OP is a type-conversion. Otherwise
+   return NULL_TREE.  */
+static tree
+ssa_name_get_cast_to_p (tree op)
+{
+  gimple stmt;
+
+  if (TREE_CODE (op) != SSA_NAME
+      || !is_gimple_assign (SSA_NAME_DEF_STMT (op)))
+    return NULL_TREE;
+  stmt = SSA_NAME_DEF_STMT (op);
+  if (!CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (stmt)))
+    return NULL_TREE;
+  return gimple_assign_rhs1 (stmt);
+}
+
 /* Simplify boolean operations if the source is known
    to be already a boolean.  */
 static bool
 simplify_truth_ops_using_ranges (gimple_stmt_iterator *gsi, gimple stmt)
 {
   enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
+  gimple stmt2 = stmt;
   tree val = NULL;
   tree op0, op1;
   value_range_t *vr;
   bool sop = false;
   bool need_conversion;
+  location_t loc = gimple_location (stmt);

   op0 = gimple_assign_rhs1 (stmt);
+  op1 = NULL_TREE;
+
+  /* Handle cases with prefixed type-cast.  */
+  if (CONVERT_EXPR_CODE_P (rhs_code)
+      && INTEGRAL_TYPE_P (TREE_TYPE (op0))
+      && TREE_CODE (op0) == SSA_NAME
+      && is_gimple_assign (SSA_NAME_DEF_STMT (op0))
+      && INTEGRAL_TYPE_P (TREE_TYPE (gimple_assign_lhs (stmt))))
+    {
+      stmt2 = SSA_NAME_DEF_STMT (op0);
+      op0 = gimple_assign_rhs1 (stmt2);
+      if (!INTEGRAL_TYPE_P (TREE_TYPE (op0)))
+	return false;
+      rhs_code = gimple_assign_rhs_code (stmt2);
+      if (rhs_code != BIT_NOT_EXPR
+	  && rhs_code != BIT_AND_EXPR
+	  && rhs_code != BIT_IOR_EXPR
+	  && rhs_code != BIT_XOR_EXPR
+	  && rhs_code != NE_EXPR && rhs_code != EQ_EXPR)
+	return false;
+
+      if (rhs_code != BIT_NOT_EXPR)
+	op1 = gimple_assign_rhs2 (stmt2);
+
+      if (gimple_has_location (stmt2))
+        loc = gimple_location (stmt2);
+    }
+  else if (CONVERT_EXPR_CODE_P (rhs_code))
+    return false;
+  else if (rhs_code != BIT_NOT_EXPR)
+    op1 = gimple_assign_rhs2 (stmt);
+
+  /* ~X is only equivalent to !X, if type-precision is one and X has
+     an integral type.  */
+  if (rhs_code == BIT_NOT_EXPR
+      && (!INTEGRAL_TYPE_P (TREE_TYPE (op0))
+	  || TYPE_PRECISION (TREE_TYPE (op0)) != 1))
+    return false;
+
   if (TYPE_PRECISION (TREE_TYPE (op0)) != 1)
     {
       if (TREE_CODE (op0) != SSA_NAME)
@@ -6775,19 +6847,83 @@ simplify_truth_ops_using_ranges (gimple_
         return false;
     }

-  if (rhs_code == BIT_NOT_EXPR && TYPE_PRECISION (TREE_TYPE (op0)) == 1)
+  need_conversion =
+    !useless_type_conversion_p (TREE_TYPE (gimple_assign_lhs (stmt)),
+			        TREE_TYPE (op0));
+  /* As comparisons X != 0 getting folded to (bool) X by VRP,
+     but X == 0 might be not folded for none boolean type of X
+     to (bool) (X ^ 1), we need to handle this case special
+     to simplify this.
+     For bitwise-binary operations we have three cases to handle:
+     a) ((bool) X) op ((bool) Y)
+     b) ((bool) X) op (Y == 0) -OR- (X == 0) op ((bool) Y)
+     c) (X == 0) op (Y == 0)
+     The later two cases can't be handled for now, as we would beed to
+     insert new statements.  */
+  if (need_conversion
+      && (rhs_code == BIT_XOR_EXPR
+	  || rhs_code == BIT_AND_EXPR
+	  || rhs_code == BIT_IOR_EXPR)
+      && TREE_CODE (op1) == SSA_NAME
+      && TREE_CODE (op0) == SSA_NAME)
     {
-      rhs_code = NE_EXPR;
-      op1 = build_int_cst (TREE_TYPE (op0), 1);
+      tree cop0 = ssa_name_get_cast_to_p (op0);
+      tree cop1 = ssa_name_get_cast_to_p (op1);
+
+      /* We would need an new statment for cases b and c, and we can't
+	 due vr table, so bail out.  */
+      if (!cop0 || !cop1)
+        return false;
+
+      if (!INTEGRAL_TYPE_P (TREE_TYPE (cop0))
+	  || !types_compatible_p (TREE_TYPE (cop0), TREE_TYPE (cop1)))
+	return false;
+
+      need_conversion =
+	!useless_type_conversion_p (TREE_TYPE (gimple_assign_lhs (stmt)),
+				    TREE_TYPE (cop0));
+      if (need_conversion)
+	return false;
+
+      op0 = cop0;
+      op1 = cop1;
+
+      /* We need to re-check if value ranges for new operands
+         for 1-bit precision/range.  */
+      if (TYPE_PRECISION (TREE_TYPE (op0)) != 1)
+	{
+	  if (TREE_CODE (op0) != SSA_NAME)
+	    return false;
+	  vr = get_value_range (op0);
+
+	  val = compare_range_with_value (GE_EXPR, vr, integer_zero_node, &sop);
+	  if (!val || !integer_onep (val))
+	    return false;
+
+	  val = compare_range_with_value (LE_EXPR, vr, integer_one_node, &sop);
+	  if (!val || !integer_onep (val))
+	    return false;
+	}
+
+      if (TYPE_PRECISION (TREE_TYPE (op1)) != 1)
+	{
+	  vr = get_value_range (op1);
+	  val = compare_range_with_value (GE_EXPR, vr, integer_zero_node, &sop);
+	  if (!val || !integer_onep (val))
+	    return false;
+
+	  val = compare_range_with_value (LE_EXPR, vr, integer_one_node, &sop);
+	  if (!val || !integer_onep (val))
+	    return false;
+	}
     }
-  else
-    {
-      op1 = gimple_assign_rhs2 (stmt);

-      /* Reduce number of cases to handle.  */
+  /* Reduce number of cases to handle.  */
+  if (op1 != NULL_TREE)
+    {
       if (is_gimple_min_invariant (op1))
 	{
-          /* Exclude anything that should have been already folded.  */
+	  /* Exclude anything that should have been already folded.  */
 	  if (rhs_code != EQ_EXPR
 	      && rhs_code != NE_EXPR
 	      && rhs_code != BIT_XOR_EXPR)
@@ -6818,32 +6954,34 @@ simplify_truth_ops_using_ranges (gimple_
 	      vr = get_value_range (op1);
 	      val = compare_range_with_value (GE_EXPR, vr, integer_zero_node, &sop);
 	      if (!val || !integer_onep (val))
-	        return false;
+		return false;

 	      val = compare_range_with_value (LE_EXPR, vr, integer_one_node, &sop);
 	      if (!val || !integer_onep (val))
-	        return false;
+		return false;
 	    }
 	}
-    }

-  if (sop && issue_strict_overflow_warning (WARN_STRICT_OVERFLOW_MISC))
-    {
-      location_t location;
+      if (sop && issue_strict_overflow_warning (WARN_STRICT_OVERFLOW_MISC))
+	{
+	  location_t location;

-      if (!gimple_has_location (stmt))
-	location = input_location;
-      else
-	location = gimple_location (stmt);
+	  if (!gimple_has_location (stmt))
+	    location = input_location;
+	  else
+	    location = gimple_location (stmt);

-      warning_at (location, OPT_Wstrict_overflow,
-		  _("assuming signed overflow does not occur when "
-		    "simplifying ==, != or ! to identity or ^"));
+	  warning_at (location, OPT_Wstrict_overflow,
+		      _("assuming signed overflow does not occur when "
+			"simplifying ==, != or ! to identity or ^"));
+	}
     }

-  need_conversion =
-    !useless_type_conversion_p (TREE_TYPE (gimple_assign_lhs (stmt)),
-			        TREE_TYPE (op0));
+  if (rhs_code == BIT_NOT_EXPR)
+    {
+      rhs_code = NE_EXPR;
+      op1 = build_int_cst (TREE_TYPE (op0), 1);
+    }

   /* Make sure to not sign-extend -1 as a boolean value.  */
   if (need_conversion
@@ -6863,6 +7001,7 @@ simplify_truth_ops_using_ranges (gimple_
 	  gimple_assign_set_rhs_with_ops (gsi,
 					  need_conversion ? NOP_EXPR : SSA_NAME,
 					  op0, NULL);
+	  gimple_set_location (stmt, loc);
 	  update_stmt (gsi_stmt (*gsi));
 	  return true;
 	}
@@ -6873,10 +7012,20 @@ simplify_truth_ops_using_ranges (gimple_
       gcc_unreachable ();
     }

+  /* We can't insert here new expression as otherwise
+     tracked vr tables getting out of bounds.  */
   if (need_conversion)
     return false;

+  /* Reduce here simple SSA_NAME assignments to other expressions.
+     This produces better results.  */
+  while ((val = ssa_name_get_inner_ssa_name_p (op0)) != NULL_TREE)
+    op0 = val;
+  while ((val = ssa_name_get_inner_ssa_name_p (op1)) != NULL_TREE)
+    op1 = val;
+
   gimple_assign_set_rhs_with_ops (gsi, rhs_code, op0, op1);
+  gimple_set_location (stmt, loc);
   update_stmt (gsi_stmt (*gsi));
   return true;
 }
@@ -7455,7 +7604,11 @@ simplify_stmt_using_ranges (gimple_stmt_
 	CASE_CONVERT:
 	  if (TREE_CODE (rhs1) == SSA_NAME
 	      && INTEGRAL_TYPE_P (TREE_TYPE (rhs1)))
-	    return simplify_conversion_using_ranges (stmt);
+	    {
+	      if (simplify_truth_ops_using_ranges (gsi, stmt))
+		return true;
+	      return simplify_conversion_using_ranges (stmt);
+	    }
 	  break;

 	default:
Index: gcc-head/gcc/testsuite/gcc.dg/tree-ssa/vrp47.c
===================================================================
--- gcc-head.orig/gcc/testsuite/gcc.dg/tree-ssa/vrp47.c
+++ gcc-head/gcc/testsuite/gcc.dg/tree-ssa/vrp47.c
@@ -4,7 +4,7 @@
    jumps when evaluating an && condition.  VRP is not able to optimize
    this.  */
 /* { dg-do compile { target { ! "mips*-*-* s390*-*-*  avr-*-*
mn10300-*-*" } } } */
-/* { dg-options "-O2 -fdump-tree-vrp -fdump-tree-dom" } */
+/* { dg-options "-O2 -fdump-tree-vrp" } */
 /* { dg-options "-O2 -fdump-tree-vrp -fdump-tree-dom -march=i586" {
target { i?86-*-* && ilp32 } } } */
