re PR tree-optimization/45633 (internal compiler error: verify_stmts failed)

	PR tree-optimization/45633
	* tree-cfg.c (verify_gimple_assign_binary): Allow
	MINUS_EXPR with lhs and rhs1 pointer vector and
	rhs2 sizetype vector.
	* expr.c (expand_expr_real_2) <case PLUS_EXPR>: For pointer
	or vector pointer use TER to optimize pointer subtraction.

	* gcc.dg/vect/pr45633.c: New test.

From-SVN: r164312

gcc/ChangeLog

+2010-09-15  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/45633
+	* tree-cfg.c (verify_gimple_assign_binary): Allow
+	MINUS_EXPR with lhs and rhs1 pointer vector and
+	rhs2 sizetype vector.
+	* expr.c (expand_expr_real_2) <case PLUS_EXPR>: For pointer
+	or vector pointer use TER to optimize pointer subtraction.
+
 2010-09-15  Jie Zhang  <jie@codesourcery.com>
 
 	* config/arm/vfp.md (cmpsf_trap_vfp): Change type from

gcc/expr.c

@@ -7572,6 +7572,24 @@ expand_expr_real_2 (sepops ops, rtx target, enum machine_mode tmode,
 	    }
 	}
 
+      /* Use TER to expand pointer addition of a negated value
+	 as pointer subtraction.  */
+      if ((POINTER_TYPE_P (TREE_TYPE (treeop0))
+	   || (TREE_CODE (TREE_TYPE (treeop0)) == VECTOR_TYPE
+	       && POINTER_TYPE_P (TREE_TYPE (TREE_TYPE (treeop0)))))
+	  && TREE_CODE (treeop1) == SSA_NAME
+	  && TYPE_MODE (TREE_TYPE (treeop0))
+	     == TYPE_MODE (TREE_TYPE (treeop1)))
+	{
+	  gimple def = get_def_for_expr (treeop1, NEGATE_EXPR);
+	  if (def)
+	    {
+	      treeop1 = gimple_assign_rhs1 (def);
+	      code = MINUS_EXPR;
+	      goto do_minus;
+	    }
+	}
+
       /* No sense saving up arithmetic to be done
 	 if it's all in the wrong mode to form part of an address.
 	 And force_operand won't know whether to sign-extend or
@@ -7593,6 +7611,7 @@ expand_expr_real_2 (sepops ops, rtx target, enum machine_mode tmode,
       return REDUCE_BIT_FIELD (simplify_gen_binary (PLUS, mode, op0, op1));
 
     case MINUS_EXPR:
+    do_minus:
       /* For initializers, we are allowed to return a MINUS of two
 	 symbolic constants.  Here we handle all cases when both operands
 	 are constant.  */

gcc/testsuite/ChangeLog

+2010-09-15  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/45633
+	* gcc.dg/vect/pr45633.c: New test.
+
 2010-09-15  Janus Weil  <janus@gcc.gnu.org>
 
 	PR fortran/45577

gcc/testsuite/gcc.dg/vect/pr45633.c

+/* PR tree-optimization/45633 */
+/* { dg-do compile } */
+
+int s[32];
+unsigned char *t[32];
+
+void
+foo (void)
+{
+  int i;
+  for (i = 0; i < 32; i++)
+    t[i] -= s[i];
+}
+
+/* { dg-final { cleanup-tree-dump "vect" } } */

gcc/tree-cfg.c

@@ -3448,8 +3448,9 @@ verify_gimple_assign_binary (gimple stmt)
       }
 
     case PLUS_EXPR:
+    case MINUS_EXPR:
       {
-	/* We use regular PLUS_EXPR for vectors.
+	/* We use regular PLUS_EXPR and MINUS_EXPR for vectors.
 	   ???  This just makes the checker happy and may not be what is
 	   intended.  */
 	if (TREE_CODE (lhs_type) == VECTOR_TYPE
@@ -3474,10 +3475,6 @@ verify_gimple_assign_binary (gimple stmt)
 	      }
 	    goto do_pointer_plus_expr_check;
 	  }
-      }
-    /* Fallthru.  */
-    case MINUS_EXPR:
-      {
 	if (POINTER_TYPE_P (lhs_type)
 	    || POINTER_TYPE_P (rhs1_type)
 	    || POINTER_TYPE_P (rhs2_type))