From: Doug Evans <dje@gnu.org>
Date: Thu, 17 Nov 1994 20:14:21 +0000 (+0000)
Subject: (expand_unop): Try subtraction from zero if there isn't a
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=b82b6eea9339954d55d1e189565f8574bd95f9e3;p=gcc.git

(expand_unop): Try subtraction from zero if there isn't a
negate library function.

From-SVN: r8485
---

diff --git a/gcc/optabs.c b/gcc/optabs.c
index db68da8f9fb..724f36b58cb 100644
--- a/gcc/optabs.c
+++ b/gcc/optabs.c
@@ -2041,6 +2041,17 @@ expand_unop (mode, unoptab, op0, target, unsignedp)
 	}
     }
 
+  /* If there is no negate operation, try doing a subtract from zero.
+     The US Software GOFAST library needs this.  */
+  if (unoptab == neg_optab)
+    {    
+      rtx temp;
+      temp = expand_binop (mode, sub_optab, CONST0_RTX (mode), op0,
+			   target, unsignedp, OPTAB_LIB_WIDEN);
+      if (temp)
+	return temp;
+    }
+      
   return 0;
 }