ply/ir.h

#ifndef _PLY_IR_H
#define _PLY_IR_H

#include <stdint.h>
#include <stdlib.h>

#include <linux/bpf.h>

typedef enum vitype {
	VI_INSN,
	VI_LABEL,
	VI_REG_GET,
	VI_REG_PUT,
} vitype_t;

typedef struct vinsn {
	vitype_t vitype;

	union {
		struct {
			struct bpf_insn bpf;
			uint16_t dst;
			uint16_t src;
		} insn;

		int16_t label;
		uint16_t reg;
	};
} vinsn_t;

typedef struct ir {
	vinsn_t *vi;
	size_t len;

	int16_t next_label;
	uint16_t next_reg;
} ir_t;

int16_t  ir_alloc_label   (ir_t *ir);
uint16_t ir_alloc_register(ir_t *ir);

void ir_emit_insn   (ir_t *ir, struct bpf_insn bpf, uint16_t dst, uint16_t src);
void ir_emit_label  (ir_t *ir, int16_t label);
void ir_emit_reg_get(ir_t *ir, uint16_t reg);
void ir_emit_reg_put(ir_t *ir, uint16_t reg);

ir_t *ir_new(void);

#endif	/* _PLY_IR_H */