Function emit_st_common

dpdk/lib/bpf/bpf_jit_x86.c:598–639

* emit one of: * mov % , (% ) * mov , (% ) */

 *   mov <imm>, <ofs>(%<dreg>)
 */
static void
emit_st_common(struct bpf_jit_state *st, uint32_t op, uint32_t sreg,
	uint32_t dreg, uint32_t imm, int32_t ofs)
{
	uint32_t mods, imsz, opsz, opx;
	const uint8_t prfx16 = 0x66;

	/* 8 bit instruction opcodes */
	static const uint8_t op8[] = {0xC6, 0x88};

	/* 16/32/64 bit instruction opcodes */
	static const uint8_t ops[] = {0xC7, 0x89};

	/* is the instruction has immediate value or src reg? */
	opx = (BPF_CLASS(op) == BPF_STX);

	opsz = BPF_SIZE(op);
	if (opsz == BPF_H)
		emit_bytes(st, &prfx16, sizeof(prfx16));

	emit_rex(st, op, sreg, dreg);

	if (opsz == BPF_B)
		emit_bytes(st, &op8[opx], sizeof(op8[opx]));
	else
		emit_bytes(st, &ops[opx], sizeof(ops[opx]));

	imsz = imm_size(ofs);
	mods = (imsz == 1) ? MOD_IDISP8 : MOD_IDISP32;

	emit_modregrm(st, mods, sreg, dreg);

	if (dreg == RSP || dreg == R12)
		emit_sib(st, SIB_SCALE_1, dreg, dreg);

	emit_imm(st, ofs, imsz);

	if (opx == 0) {
		imsz = RTE_MIN(bpf_size(opsz), sizeof(imm));
		emit_imm(st, imm, imsz);
	}
}

static void
emit_st_imm(struct bpf_jit_state *st, uint32_t op, uint32_t dreg, uint32_t imm,