2 files changed, 4 insertions, 1 deletions
diff --git a/simplify.c b/simplify.c
index ec9c5211..be8d461e 100644
--- a/simplify.c
+++ b/simplify.c
@@ -1191,6 +1191,10 @@ static int simplify_cast(struct instruction *insn)
 		break;
 	case OP_FPCMP ... OP_BINCMP_END:
 		switch (insn->opcode) {
+		case OP_SEXT:
+			if (insn->size == 1)
+				break;
+			/* fall through */
 		case OP_ZEXT:
 			// simplify:
 			//	setcc.n	%t <- %a, %b
diff --git a/validation/optim/setne0-sext.c b/validation/optim/setne0-sext.c
index 565f8df2..4167979b 100644
--- a/validation/optim/setne0-sext.c
+++ b/validation/optim/setne0-sext.c
@@ -3,7 +3,6 @@ long foo(int a) { return a != 0; }
 /*
  * check-name: setne0-sext
  * check-command: test-linearize -m64 -Wno-decl $file
- * check-known-to-fail
  *
  * check-output-ignore
  * check-output-excludes: sext\\.