#include <assert.h>

#include "ir.h"

const uint16_t vreg_base = 0x8000;

static void ir_emit(ir_t *ir, vinsn_t *vi)
{
	ir->vi = realloc(ir->vi, ++ir->len);
	assert(ir->vi);

	ir->vi[ir->len - 1] = *vi;
}

void ir_emit_insn(ir_t *ir, struct bpf_insn bpf, uint16_t dst, uint16_t src)
{
	vinsn_t vi;

	vi.vitype = VI_INSN;
	vi.insn.bpf = bpf;
	vi.insn.dst = dst;
	vi.insn.src = src;
	ir_emit(ir, &vi);
}

void ir_emit_label  (ir_t *ir, int16_t label)
{
	vinsn_t vi;

	vi.vitype = VI_LABEL;
	vi.label = label;
}

void ir_emit_reg_get(ir_t *ir, uint16_t reg)
{
	vinsn_t vi;

	vi.vitype = VI_REG_GET;
	vi.reg = reg;
}

void ir_emit_reg_put(ir_t *ir, uint16_t reg)
{
	vinsn_t vi;

	vi.vitype = VI_REG_PUT;
	vi.reg = reg;
}

int16_t ir_alloc_label (ir_t *ir)
{
	return ir->next_label--;
}

uint16_t ir_alloc_register(ir_t *ir)
{
	return ir->next_reg++;
}

ir_t *ir_new(void)
{
	ir_t *ir;

	ir = calloc(1, sizeof(*ir));
	assert(ir);

	ir->next_reg = vreg_base;
	ir->next_label = -1;
	return ir;
}