From 551064b16e9a308ebc279316494adc2763e48a5d Mon Sep 17 00:00:00 2001
From: Richard Stallman <rms@gnu.org>
Date: Sun, 18 Jul 1993 20:24:45 +0000
Subject: [PATCH] (fold): Handle CONJ_EXPR.

From-SVN: r4938
---
 gcc/fold-const.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index de5630bf0f3..5b9d8511cbe 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -3485,6 +3485,30 @@ fold (expr)
 	return build1 (ABS_EXPR, type, TREE_OPERAND (arg0, 0));
       return t;
 
+    case CONJ_EXPR:
+      if (TREE_CODE (TREE_TYPE (arg0)) != COMPLEX_TYPE)
+	return arg0;
+      else if (TREE_CODE (arg0) == COMPLEX_EXPR)
+	return build (COMPLEX_EXPR, TREE_TYPE (arg0),
+		      TREE_OPERAND (arg0, 0),
+		      fold (build1 (NEGATE_EXPR,
+				    TREE_TYPE (TREE_TYPE (arg0)),
+				    TREE_OPERAND (arg0, 1))));
+      else if (TREE_CODE (arg0) == COMPLEX_CST)
+	return build_complex (TREE_OPERAND (arg0, 0),
+			      fold (build1 (NEGATE_EXPR,
+					    TREE_TYPE (TREE_TYPE (arg0)),
+					    TREE_OPERAND (arg0, 1))));
+      else if (TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR)
+	return fold (build (TREE_CODE (arg0), type,
+			    fold (build1 (CONJ_EXPR, type,
+					  TREE_OPERAND (arg0, 0))),
+			    fold (build1 (CONJ_EXPR,
+					  type, TREE_OPERAND (arg0, 1)))));
+      else if (TREE_CODE (arg0) == CONJ_EXPR)
+	return TREE_OPERAND (arg0, 0);
+      return t;
+
     case BIT_NOT_EXPR:
       if (wins)
 	{
-- 
2.30.2