--- /dev/null
+/*
+ * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
+ * See the copyright notice in the ACK home directory, in the file "Copyright".
+ */
+/* Contents of flags used when describing interpreter opcodes */
+
+#define RCS_IP "$Header$"
+
+#define OPTYPE 07 /* type field in flag */
+
+#define OPMINI 0 /* m MINI */
+#define OPSHORT 1 /* s SHORT */
+#define OPNO 2 /* - No operand */
+#define OP8 3 /* 1 1-byte signed operand */
+#define OP16 4 /* 2 2-byte signed operand */
+#define OP32 5 /* 4 4-byte signed operand */
+#define OP64 6 /* 8 8-byte signed operand */
+#define OP16U 7 /* u 2-byte unsigned operand */
+
+#define OPESC 010 /* e escaped opcode */
+#define OPWORD 020 /* w operand is word multiple */
+#define OPNZ 040 /* o operand starts at 1 ( or wordsize if w-flag) */
+
+#define OPRANGE 0300 /* Range of operands: Positive, negative, both */
+
+#define OP_BOTH 0000 /* the default */
+#define OP_POS 0100 /* p Positive (>=0) operands only */
+#define OP_NEG 0200 /* n Negative (<0) operands only */
+
+struct opform {
+ char i_opcode ; /* the opcode number */
+ char i_flag ; /* the flag byte */
+ char i_low ; /* the interpreter first opcode */
+ char i_num ; /* the number of shorts/minis (optional) */
+};
+
+/* Escape indicators */
+
+#define ESC 254 /* To escape group */
+#define ESC_L 255 /* To 32 and 64 bit operands */