2 files changed, 2 insertions, 1 deletions
diff --git a/simplify.c b/simplify.c
index cb401d8f..08b706ca 100644
--- a/simplify.c
+++ b/simplify.c
@@ -1390,6 +1390,8 @@ static int simplify_sub(struct instruction *insn)
 	case OP_ADD:
 		if (def->src1 == src2)		// (x + y) - x --> y
 			return replace_with_pseudo(insn, def->src2);
+		if (def->src2 == src2)		// (x + y) - y --> x
+			return replace_with_pseudo(insn, def->src1);
 		break;
 	}
 
diff --git a/validation/optim/simplify-same-add-subr.c b/validation/optim/simplify-same-add-subr.c
index e8540703..071021c4 100644
--- a/validation/optim/simplify-same-add-subr.c
+++ b/validation/optim/simplify-same-add-subr.c
@@ -3,7 +3,6 @@ int add_subr(int x, int y) { return (x + y) - y; }
 /*
  * check-name: simplify-same-add-subr
  * check-command: test-linearize -Wno-decl $file
- * check-known-to-fail
  *
  * check-output-start
 add_subr: