re PR tree-optimization/20490 (ICE: verify_stmts failed. (with -O -ftree-pre))

2005-03-16  Daniel Berlin  <dberlin@dberlin.org>

	Fix PR tree-optimization/20940

	* tree-ssa-pre.c (create_expression_by_pieces): Use
	force_gimple_operand on result of fold.

From-SVN: r96560

gcc/ChangeLog

+2005-03-16  Daniel Berlin  <dberlin@dberlin.org>
+
+	Fix PR tree-optimization/20940
+	
+	* tree-ssa-pre.c (create_expression_by_pieces): Use
+	force_gimple_operand on result of fold.
+
 2005-03-16  Andrew Pinski  <pinskia@physics.uc.edu>
 
 	* config/i386/emmintrin.h (_mm_extract_epi16): Correct the number

gcc/testsuite/gcc.dg/tree-ssa/pr20940.c

+/* { dg-do compile } */
+/* { dg-options "-O -ftree-pre" } */
+static int  a;
+static int  b;
+
+typedef int gint;
+
+int blah ()
+{
+	gint x = a;
+	gint y = b;
+
+	x *= (x < 0) ? -1 : 0;
+	y *= (y < 0) ? -1 : 0;
+
+	return (y * x);
+
+}
+
+

gcc/tree-ssa-pre.c

@@ -1317,16 +1317,25 @@ create_expression_by_pieces (basic_block block, tree expr, tree stmts)
     case tcc_binary:
       {
 	tree_stmt_iterator tsi;
+	tree forced_stmts;
 	tree genop1, genop2;
 	tree temp;
+	tree folded;
 	tree op1 = TREE_OPERAND (expr, 0);
 	tree op2 = TREE_OPERAND (expr, 1);
 	genop1 = find_or_generate_expression (block, op1, stmts);
 	genop2 = find_or_generate_expression (block, op2, stmts);
 	temp = create_tmp_var (TREE_TYPE (expr), "pretmp");
 	add_referenced_tmp_var (temp);
-	newexpr = fold (build (TREE_CODE (expr), TREE_TYPE (expr), 
-			       genop1, genop2));
+	
+	folded = fold (build (TREE_CODE (expr), TREE_TYPE (expr), 
+			      genop1, genop2));
+	newexpr = force_gimple_operand (folded, &forced_stmts, false, NULL);
+	if (forced_stmts)
+	  {
+	    tsi = tsi_last (stmts);
+	    tsi_link_after (&tsi, forced_stmts, TSI_CONTINUE_LINKING);
+	  }
 	newexpr = build (MODIFY_EXPR, TREE_TYPE (expr),
 			 temp, newexpr);
 	NECESSARY (newexpr) = 0;
@@ -1341,14 +1350,22 @@ create_expression_by_pieces (basic_block block, tree expr, tree stmts)
     case tcc_unary:
       {
 	tree_stmt_iterator tsi;
+	tree forced_stmts;
 	tree genop1;
 	tree temp;
+	tree folded;
 	tree op1 = TREE_OPERAND (expr, 0);
 	genop1 = find_or_generate_expression (block, op1, stmts);
 	temp = create_tmp_var (TREE_TYPE (expr), "pretmp");
 	add_referenced_tmp_var (temp);
-	newexpr = fold (build (TREE_CODE (expr), TREE_TYPE (expr), 
-			       genop1));
+	folded = fold (build (TREE_CODE (expr), TREE_TYPE (expr), 
+			      genop1));
+	newexpr = force_gimple_operand (folded, &forced_stmts, false, NULL);
+	if (forced_stmts)
+	  {
+	    tsi = tsi_last (stmts);
+	    tsi_link_after (&tsi, forced_stmts, TSI_CONTINUE_LINKING);
+	  }
 	newexpr = build (MODIFY_EXPR, TREE_TYPE (expr),
 			 temp, newexpr);
 	name = make_ssa_name (temp, newexpr);