[libc] optimize _isascii

mateoconlechuga · mateoconlechuga · commit cb31b9e83c5a · 2024-10-24T20:41:55.000-06:00
diff --git a/src/libc/isascii.src b/src/libc/isascii.src
@@ -6,8 +6,7 @@ _isascii:
 	pop	de
 	ex	(sp),hl
 	push	de
-	ld	de,-128
-	add	hl,de
+	sla	l
 	sbc	hl,hl
 	inc	hl
 	ret
