From: Roger Sayle <roger@nextmovesoftware.com>
Date: Wed, 24 Jun 2020 18:48:43 +0000 (+0000)
Subject: simplify-rtx: Parity of parity is parity
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=35eca8c5e16933b5cdb17eac4ed51e6b3877b288;p=gcc.git

simplify-rtx: Parity of parity is parity

2020-06-24  Roger Sayle  <roger@nextmovesoftware.com>

	* simplify-rtx.c (simplify_unary_operation_1): Simplify
	(parity (parity x)) as (parity x), i.e. PARITY is idempotent.
---

diff --git a/gcc/simplify-rtx.c b/gcc/simplify-rtx.c
index 28c2dc69ae7..65008eaab45 100644
--- a/gcc/simplify-rtx.c
+++ b/gcc/simplify-rtx.c
@@ -1391,6 +1391,10 @@ simplify_unary_operation_1 (enum rtx_code code, machine_mode mode, rtx op)
 				       GET_MODE (XEXP (op, 0)));
 	  break;
 
+	case PARITY:
+	  /* (parity (parity x)) -> parity (x).  */
+	  return op;
+
 	default:
 	  break;
 	}