* Merge from gcc2 June 9, 1998 snapshot. See ChangeLog.13 for

        details.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@20808 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 19 insertions, 10 deletions

diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index 7544f8b673a..8849608795a 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -3293,14 +3293,16 @@ fold_range_test (exp)
 	   && operand_equal_p (lhs, rhs, 0))
     {
       /* If simple enough, just rewrite.  Otherwise, make a SAVE_EXPR
-	 unless we are at top level, in which case we can't do this.  */
+	 unless we are at top level or LHS contains a PLACEHOLDER_EXPR, in
+	 which cases we can't do this.  */
       if (simple_operand_p (lhs))
 	return build (TREE_CODE (exp) == TRUTH_ANDIF_EXPR
 		      ? TRUTH_AND_EXPR : TRUTH_OR_EXPR,
 		      TREE_TYPE (exp), TREE_OPERAND (exp, 0),
 		      TREE_OPERAND (exp, 1));
 
-      else if (current_function_decl != 0)
+      else if (current_function_decl != 0
+	       && ! contains_placeholder_p (lhs))
 	{
 	  tree common = save_expr (lhs);
 
@@ -3997,7 +3999,9 @@ fold (expr)
       else if ((TREE_CODE (arg1) == COND_EXPR
 		|| (TREE_CODE_CLASS (TREE_CODE (arg1)) == '<'
 		    && TREE_CODE_CLASS (code) != '<'))
-	       && (! TREE_SIDE_EFFECTS (arg0) || current_function_decl != 0))
+	       && (! TREE_SIDE_EFFECTS (arg0)
+		   || (current_function_decl != 0
+		       && ! contains_placeholder_p (arg0))))
 	{
 	  tree test, true_value, false_value;
 	  tree lhs = 0, rhs = 0;
@@ -4068,7 +4072,9 @@ fold (expr)
       else if ((TREE_CODE (arg0) == COND_EXPR
 		|| (TREE_CODE_CLASS (TREE_CODE (arg0)) == '<'
 		    && TREE_CODE_CLASS (code) != '<'))
-	       && (! TREE_SIDE_EFFECTS (arg1) || current_function_decl != 0))
+	       && (! TREE_SIDE_EFFECTS (arg1)
+		   || (current_function_decl != 0
+		       && ! contains_placeholder_p (arg1))))
 	{
 	  tree test, true_value, false_value;
 	  tree lhs = 0, rhs = 0;
@@ -4633,7 +4639,8 @@ fold (expr)
 	  if (real_onep (arg1))
 	    return non_lvalue (convert (type, arg0));
 	  /* x*2 is x+x */
-	  if (! wins && real_twop (arg1) && current_function_decl != 0)
+	  if (! wins && real_twop (arg1) && current_function_decl != 0
+	      && ! contains_placeholder_p (arg0))
 	    {
 	      tree arg = save_expr (arg0);
 	      return build (PLUS_EXPR, type, arg, arg);
@@ -5656,14 +5663,16 @@ fold (expr)
 	  return t1 ? t1 : t;
 	}
 
-      /* If this is a comparison of complex values and either or both
-	 sizes are a COMPLEX_EXPR, it is best to split up the comparisons
-	 and join them with a TRUTH_ANDIF_EXPR or TRUTH_ORIF_EXPR.  This
-	 may prevent needless evaluations.  */
+      /* If this is a comparison of complex values and either or both sides
+	 are a COMPLEX_EXPR or COMPLEX_CST, it is best to split up the
+	 comparisons and join them with a TRUTH_ANDIF_EXPR or TRUTH_ORIF_EXPR.
+	 This may prevent needless evaluations.  */
       if ((code == EQ_EXPR || code == NE_EXPR)
 	  && TREE_CODE (TREE_TYPE (arg0)) == COMPLEX_TYPE
 	  && (TREE_CODE (arg0) == COMPLEX_EXPR
-	      || TREE_CODE (arg1) == COMPLEX_EXPR))
+	      || TREE_CODE (arg1) == COMPLEX_EXPR
+	      || TREE_CODE (arg0) == COMPLEX_CST
+	      || TREE_CODE (arg1) == COMPLEX_CST))
 	{
 	  tree subtype = TREE_TYPE (TREE_TYPE (arg0));
 	  tree real0, imag0, real1, imag1;