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-rw-r--r--arch/arm64/lib/insn.c471
1 files changed, 292 insertions, 179 deletions
diff --git a/arch/arm64/lib/insn.c b/arch/arm64/lib/insn.c
index b506a4b1e38c..4e298baddc2e 100644
--- a/arch/arm64/lib/insn.c
+++ b/arch/arm64/lib/insn.c
@@ -5,6 +5,7 @@
*
* Copyright (C) 2014-2016 Zi Shen Lim <zlim.lnx@gmail.com>
*/
+#include <linux/bitfield.h>
#include <linux/bitops.h>
#include <linux/bug.h>
#include <linux/printk.h>
@@ -20,91 +21,6 @@
#define AARCH64_INSN_N_BIT BIT(22)
#define AARCH64_INSN_LSL_12 BIT(22)
-static const int aarch64_insn_encoding_class[] = {
- AARCH64_INSN_CLS_UNKNOWN,
- AARCH64_INSN_CLS_UNKNOWN,
- AARCH64_INSN_CLS_SVE,
- AARCH64_INSN_CLS_UNKNOWN,
- AARCH64_INSN_CLS_LDST,
- AARCH64_INSN_CLS_DP_REG,
- AARCH64_INSN_CLS_LDST,
- AARCH64_INSN_CLS_DP_FPSIMD,
- AARCH64_INSN_CLS_DP_IMM,
- AARCH64_INSN_CLS_DP_IMM,
- AARCH64_INSN_CLS_BR_SYS,
- AARCH64_INSN_CLS_BR_SYS,
- AARCH64_INSN_CLS_LDST,
- AARCH64_INSN_CLS_DP_REG,
- AARCH64_INSN_CLS_LDST,
- AARCH64_INSN_CLS_DP_FPSIMD,
-};
-
-enum aarch64_insn_encoding_class __kprobes aarch64_get_insn_class(u32 insn)
-{
- return aarch64_insn_encoding_class[(insn >> 25) & 0xf];
-}
-
-bool __kprobes aarch64_insn_is_steppable_hint(u32 insn)
-{
- if (!aarch64_insn_is_hint(insn))
- return false;
-
- switch (insn & 0xFE0) {
- case AARCH64_INSN_HINT_XPACLRI:
- case AARCH64_INSN_HINT_PACIA_1716:
- case AARCH64_INSN_HINT_PACIB_1716:
- case AARCH64_INSN_HINT_PACIAZ:
- case AARCH64_INSN_HINT_PACIASP:
- case AARCH64_INSN_HINT_PACIBZ:
- case AARCH64_INSN_HINT_PACIBSP:
- case AARCH64_INSN_HINT_BTI:
- case AARCH64_INSN_HINT_BTIC:
- case AARCH64_INSN_HINT_BTIJ:
- case AARCH64_INSN_HINT_BTIJC:
- case AARCH64_INSN_HINT_NOP:
- return true;
- default:
- return false;
- }
-}
-
-bool aarch64_insn_is_branch_imm(u32 insn)
-{
- return (aarch64_insn_is_b(insn) || aarch64_insn_is_bl(insn) ||
- aarch64_insn_is_tbz(insn) || aarch64_insn_is_tbnz(insn) ||
- aarch64_insn_is_cbz(insn) || aarch64_insn_is_cbnz(insn) ||
- aarch64_insn_is_bcond(insn));
-}
-
-bool __kprobes aarch64_insn_uses_literal(u32 insn)
-{
- /* ldr/ldrsw (literal), prfm */
-
- return aarch64_insn_is_ldr_lit(insn) ||
- aarch64_insn_is_ldrsw_lit(insn) ||
- aarch64_insn_is_adr_adrp(insn) ||
- aarch64_insn_is_prfm_lit(insn);
-}
-
-bool __kprobes aarch64_insn_is_branch(u32 insn)
-{
- /* b, bl, cb*, tb*, ret*, b.cond, br*, blr* */
-
- return aarch64_insn_is_b(insn) ||
- aarch64_insn_is_bl(insn) ||
- aarch64_insn_is_cbz(insn) ||
- aarch64_insn_is_cbnz(insn) ||
- aarch64_insn_is_tbz(insn) ||
- aarch64_insn_is_tbnz(insn) ||
- aarch64_insn_is_ret(insn) ||
- aarch64_insn_is_ret_auth(insn) ||
- aarch64_insn_is_br(insn) ||
- aarch64_insn_is_br_auth(insn) ||
- aarch64_insn_is_blr(insn) ||
- aarch64_insn_is_blr_auth(insn) ||
- aarch64_insn_is_bcond(insn);
-}
-
static int __kprobes aarch64_get_imm_shift_mask(enum aarch64_insn_imm_type type,
u32 *maskp, int *shiftp)
{
@@ -185,7 +101,7 @@ u64 aarch64_insn_decode_immediate(enum aarch64_insn_imm_type type, u32 insn)
break;
default:
if (aarch64_get_imm_shift_mask(type, &mask, &shift) < 0) {
- pr_err("aarch64_insn_decode_immediate: unknown immediate encoding %d\n",
+ pr_err("%s: unknown immediate encoding %d\n", __func__,
type);
return 0;
}
@@ -215,7 +131,7 @@ u32 __kprobes aarch64_insn_encode_immediate(enum aarch64_insn_imm_type type,
break;
default:
if (aarch64_get_imm_shift_mask(type, &mask, &shift) < 0) {
- pr_err("aarch64_insn_encode_immediate: unknown immediate encoding %d\n",
+ pr_err("%s: unknown immediate encoding %d\n", __func__,
type);
return AARCH64_BREAK_FAULT;
}
@@ -299,36 +215,31 @@ static u32 aarch64_insn_encode_register(enum aarch64_insn_register_type type,
return insn;
}
+static const u32 aarch64_insn_ldst_size[] = {
+ [AARCH64_INSN_SIZE_8] = 0,
+ [AARCH64_INSN_SIZE_16] = 1,
+ [AARCH64_INSN_SIZE_32] = 2,
+ [AARCH64_INSN_SIZE_64] = 3,
+};
+
static u32 aarch64_insn_encode_ldst_size(enum aarch64_insn_size_type type,
u32 insn)
{
u32 size;
- switch (type) {
- case AARCH64_INSN_SIZE_8:
- size = 0;
- break;
- case AARCH64_INSN_SIZE_16:
- size = 1;
- break;
- case AARCH64_INSN_SIZE_32:
- size = 2;
- break;
- case AARCH64_INSN_SIZE_64:
- size = 3;
- break;
- default:
+ if (type < AARCH64_INSN_SIZE_8 || type > AARCH64_INSN_SIZE_64) {
pr_err("%s: unknown size encoding %d\n", __func__, type);
return AARCH64_BREAK_FAULT;
}
+ size = aarch64_insn_ldst_size[type];
insn &= ~GENMASK(31, 30);
insn |= size << 30;
return insn;
}
-static inline long branch_imm_common(unsigned long pc, unsigned long addr,
+static inline long label_imm_common(unsigned long pc, unsigned long addr,
long range)
{
long offset;
@@ -359,7 +270,7 @@ u32 __kprobes aarch64_insn_gen_branch_imm(unsigned long pc, unsigned long addr,
* ARM64 virtual address arrangement guarantees all kernel and module
* texts are within +/-128M.
*/
- offset = branch_imm_common(pc, addr, SZ_128M);
+ offset = label_imm_common(pc, addr, SZ_128M);
if (offset >= SZ_128M)
return AARCH64_BREAK_FAULT;
@@ -387,7 +298,7 @@ u32 aarch64_insn_gen_comp_branch_imm(unsigned long pc, unsigned long addr,
u32 insn;
long offset;
- offset = branch_imm_common(pc, addr, SZ_1M);
+ offset = label_imm_common(pc, addr, SZ_1M);
if (offset >= SZ_1M)
return AARCH64_BREAK_FAULT;
@@ -426,7 +337,7 @@ u32 aarch64_insn_gen_cond_branch_imm(unsigned long pc, unsigned long addr,
u32 insn;
long offset;
- offset = branch_imm_common(pc, addr, SZ_1M);
+ offset = label_imm_common(pc, addr, SZ_1M);
insn = aarch64_insn_get_bcond_value();
@@ -440,16 +351,6 @@ u32 aarch64_insn_gen_cond_branch_imm(unsigned long pc, unsigned long addr,
offset >> 2);
}
-u32 __kprobes aarch64_insn_gen_hint(enum aarch64_insn_hint_cr_op op)
-{
- return aarch64_insn_get_hint_value() | op;
-}
-
-u32 __kprobes aarch64_insn_gen_nop(void)
-{
- return aarch64_insn_gen_hint(AARCH64_INSN_HINT_NOP);
-}
-
u32 aarch64_insn_gen_branch_reg(enum aarch64_insn_register reg,
enum aarch64_insn_branch_type type)
{
@@ -485,6 +386,9 @@ u32 aarch64_insn_gen_load_store_reg(enum aarch64_insn_register reg,
case AARCH64_INSN_LDST_LOAD_REG_OFFSET:
insn = aarch64_insn_get_ldr_reg_value();
break;
+ case AARCH64_INSN_LDST_SIGNED_LOAD_REG_OFFSET:
+ insn = aarch64_insn_get_signed_ldr_reg_value();
+ break;
case AARCH64_INSN_LDST_STORE_REG_OFFSET:
insn = aarch64_insn_get_str_reg_value();
break;
@@ -504,6 +408,75 @@ u32 aarch64_insn_gen_load_store_reg(enum aarch64_insn_register reg,
offset);
}
+u32 aarch64_insn_gen_load_store_imm(enum aarch64_insn_register reg,
+ enum aarch64_insn_register base,
+ unsigned int imm,
+ enum aarch64_insn_size_type size,
+ enum aarch64_insn_ldst_type type)
+{
+ u32 insn;
+ u32 shift;
+
+ if (size < AARCH64_INSN_SIZE_8 || size > AARCH64_INSN_SIZE_64) {
+ pr_err("%s: unknown size encoding %d\n", __func__, type);
+ return AARCH64_BREAK_FAULT;
+ }
+
+ shift = aarch64_insn_ldst_size[size];
+ if (imm & ~(BIT(12 + shift) - BIT(shift))) {
+ pr_err("%s: invalid imm: %d\n", __func__, imm);
+ return AARCH64_BREAK_FAULT;
+ }
+
+ imm >>= shift;
+
+ switch (type) {
+ case AARCH64_INSN_LDST_LOAD_IMM_OFFSET:
+ insn = aarch64_insn_get_ldr_imm_value();
+ break;
+ case AARCH64_INSN_LDST_SIGNED_LOAD_IMM_OFFSET:
+ insn = aarch64_insn_get_signed_load_imm_value();
+ break;
+ case AARCH64_INSN_LDST_STORE_IMM_OFFSET:
+ insn = aarch64_insn_get_str_imm_value();
+ break;
+ default:
+ pr_err("%s: unknown load/store encoding %d\n", __func__, type);
+ return AARCH64_BREAK_FAULT;
+ }
+
+ insn = aarch64_insn_encode_ldst_size(size, insn);
+
+ insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RT, insn, reg);
+
+ insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RN, insn,
+ base);
+
+ return aarch64_insn_encode_immediate(AARCH64_INSN_IMM_12, insn, imm);
+}
+
+u32 aarch64_insn_gen_load_literal(unsigned long pc, unsigned long addr,
+ enum aarch64_insn_register reg,
+ bool is64bit)
+{
+ u32 insn;
+ long offset;
+
+ offset = label_imm_common(pc, addr, SZ_1M);
+ if (offset >= SZ_1M)
+ return AARCH64_BREAK_FAULT;
+
+ insn = aarch64_insn_get_ldr_lit_value();
+
+ if (is64bit)
+ insn |= BIT(30);
+
+ insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RT, insn, reg);
+
+ return aarch64_insn_encode_immediate(AARCH64_INSN_IMM_19, insn,
+ offset >> 2);
+}
+
u32 aarch64_insn_gen_load_store_pair(enum aarch64_insn_register reg1,
enum aarch64_insn_register reg2,
enum aarch64_insn_register base,
@@ -568,6 +541,35 @@ u32 aarch64_insn_gen_load_store_pair(enum aarch64_insn_register reg1,
offset >> shift);
}
+u32 aarch64_insn_gen_load_acq_store_rel(enum aarch64_insn_register reg,
+ enum aarch64_insn_register base,
+ enum aarch64_insn_size_type size,
+ enum aarch64_insn_ldst_type type)
+{
+ u32 insn;
+
+ switch (type) {
+ case AARCH64_INSN_LDST_LOAD_ACQ:
+ insn = aarch64_insn_get_load_acq_value();
+ break;
+ case AARCH64_INSN_LDST_STORE_REL:
+ insn = aarch64_insn_get_store_rel_value();
+ break;
+ default:
+ pr_err("%s: unknown load-acquire/store-release encoding %d\n",
+ __func__, type);
+ return AARCH64_BREAK_FAULT;
+ }
+
+ insn = aarch64_insn_encode_ldst_size(size, insn);
+
+ insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RT, insn,
+ reg);
+
+ return aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RN, insn,
+ base);
+}
+
u32 aarch64_insn_gen_load_store_ex(enum aarch64_insn_register reg,
enum aarch64_insn_register base,
enum aarch64_insn_register state,
@@ -578,10 +580,16 @@ u32 aarch64_insn_gen_load_store_ex(enum aarch64_insn_register reg,
switch (type) {
case AARCH64_INSN_LDST_LOAD_EX:
+ case AARCH64_INSN_LDST_LOAD_ACQ_EX:
insn = aarch64_insn_get_load_ex_value();
+ if (type == AARCH64_INSN_LDST_LOAD_ACQ_EX)
+ insn |= BIT(15);
break;
case AARCH64_INSN_LDST_STORE_EX:
+ case AARCH64_INSN_LDST_STORE_REL_EX:
insn = aarch64_insn_get_store_ex_value();
+ if (type == AARCH64_INSN_LDST_STORE_REL_EX)
+ insn |= BIT(15);
break;
default:
pr_err("%s: unknown load/store exclusive encoding %d\n", __func__, type);
@@ -603,12 +611,65 @@ u32 aarch64_insn_gen_load_store_ex(enum aarch64_insn_register reg,
state);
}
-u32 aarch64_insn_gen_ldadd(enum aarch64_insn_register result,
- enum aarch64_insn_register address,
- enum aarch64_insn_register value,
- enum aarch64_insn_size_type size)
+#ifdef CONFIG_ARM64_LSE_ATOMICS
+static u32 aarch64_insn_encode_ldst_order(enum aarch64_insn_mem_order_type type,
+ u32 insn)
+{
+ u32 order;
+
+ switch (type) {
+ case AARCH64_INSN_MEM_ORDER_NONE:
+ order = 0;
+ break;
+ case AARCH64_INSN_MEM_ORDER_ACQ:
+ order = 2;
+ break;
+ case AARCH64_INSN_MEM_ORDER_REL:
+ order = 1;
+ break;
+ case AARCH64_INSN_MEM_ORDER_ACQREL:
+ order = 3;
+ break;
+ default:
+ pr_err("%s: unknown mem order %d\n", __func__, type);
+ return AARCH64_BREAK_FAULT;
+ }
+
+ insn &= ~GENMASK(23, 22);
+ insn |= order << 22;
+
+ return insn;
+}
+
+u32 aarch64_insn_gen_atomic_ld_op(enum aarch64_insn_register result,
+ enum aarch64_insn_register address,
+ enum aarch64_insn_register value,
+ enum aarch64_insn_size_type size,
+ enum aarch64_insn_mem_atomic_op op,
+ enum aarch64_insn_mem_order_type order)
{
- u32 insn = aarch64_insn_get_ldadd_value();
+ u32 insn;
+
+ switch (op) {
+ case AARCH64_INSN_MEM_ATOMIC_ADD:
+ insn = aarch64_insn_get_ldadd_value();
+ break;
+ case AARCH64_INSN_MEM_ATOMIC_CLR:
+ insn = aarch64_insn_get_ldclr_value();
+ break;
+ case AARCH64_INSN_MEM_ATOMIC_EOR:
+ insn = aarch64_insn_get_ldeor_value();
+ break;
+ case AARCH64_INSN_MEM_ATOMIC_SET:
+ insn = aarch64_insn_get_ldset_value();
+ break;
+ case AARCH64_INSN_MEM_ATOMIC_SWP:
+ insn = aarch64_insn_get_swp_value();
+ break;
+ default:
+ pr_err("%s: unimplemented mem atomic op %d\n", __func__, op);
+ return AARCH64_BREAK_FAULT;
+ }
switch (size) {
case AARCH64_INSN_SIZE_32:
@@ -621,6 +682,8 @@ u32 aarch64_insn_gen_ldadd(enum aarch64_insn_register result,
insn = aarch64_insn_encode_ldst_size(size, insn);
+ insn = aarch64_insn_encode_ldst_order(order, insn);
+
insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RT, insn,
result);
@@ -631,87 +694,68 @@ u32 aarch64_insn_gen_ldadd(enum aarch64_insn_register result,
value);
}
-u32 aarch64_insn_gen_stadd(enum aarch64_insn_register address,
- enum aarch64_insn_register value,
- enum aarch64_insn_size_type size)
-{
- /*
- * STADD is simply encoded as an alias for LDADD with XZR as
- * the destination register.
- */
- return aarch64_insn_gen_ldadd(AARCH64_INSN_REG_ZR, address,
- value, size);
-}
-
-static u32 aarch64_insn_encode_prfm_imm(enum aarch64_insn_prfm_type type,
- enum aarch64_insn_prfm_target target,
- enum aarch64_insn_prfm_policy policy,
- u32 insn)
+static u32 aarch64_insn_encode_cas_order(enum aarch64_insn_mem_order_type type,
+ u32 insn)
{
- u32 imm_type = 0, imm_target = 0, imm_policy = 0;
+ u32 order;
switch (type) {
- case AARCH64_INSN_PRFM_TYPE_PLD:
+ case AARCH64_INSN_MEM_ORDER_NONE:
+ order = 0;
break;
- case AARCH64_INSN_PRFM_TYPE_PLI:
- imm_type = BIT(0);
- break;
- case AARCH64_INSN_PRFM_TYPE_PST:
- imm_type = BIT(1);
- break;
- default:
- pr_err("%s: unknown prfm type encoding %d\n", __func__, type);
- return AARCH64_BREAK_FAULT;
- }
-
- switch (target) {
- case AARCH64_INSN_PRFM_TARGET_L1:
+ case AARCH64_INSN_MEM_ORDER_ACQ:
+ order = BIT(22);
break;
- case AARCH64_INSN_PRFM_TARGET_L2:
- imm_target = BIT(0);
+ case AARCH64_INSN_MEM_ORDER_REL:
+ order = BIT(15);
break;
- case AARCH64_INSN_PRFM_TARGET_L3:
- imm_target = BIT(1);
+ case AARCH64_INSN_MEM_ORDER_ACQREL:
+ order = BIT(15) | BIT(22);
break;
default:
- pr_err("%s: unknown prfm target encoding %d\n", __func__, target);
+ pr_err("%s: unknown mem order %d\n", __func__, type);
return AARCH64_BREAK_FAULT;
}
- switch (policy) {
- case AARCH64_INSN_PRFM_POLICY_KEEP:
- break;
- case AARCH64_INSN_PRFM_POLICY_STRM:
- imm_policy = BIT(0);
+ insn &= ~(BIT(15) | BIT(22));
+ insn |= order;
+
+ return insn;
+}
+
+u32 aarch64_insn_gen_cas(enum aarch64_insn_register result,
+ enum aarch64_insn_register address,
+ enum aarch64_insn_register value,
+ enum aarch64_insn_size_type size,
+ enum aarch64_insn_mem_order_type order)
+{
+ u32 insn;
+
+ switch (size) {
+ case AARCH64_INSN_SIZE_32:
+ case AARCH64_INSN_SIZE_64:
break;
default:
- pr_err("%s: unknown prfm policy encoding %d\n", __func__, policy);
+ pr_err("%s: unimplemented size encoding %d\n", __func__, size);
return AARCH64_BREAK_FAULT;
}
- /* In this case, imm5 is encoded into Rt field. */
- insn &= ~GENMASK(4, 0);
- insn |= imm_policy | (imm_target << 1) | (imm_type << 3);
-
- return insn;
-}
+ insn = aarch64_insn_get_cas_value();
-u32 aarch64_insn_gen_prefetch(enum aarch64_insn_register base,
- enum aarch64_insn_prfm_type type,
- enum aarch64_insn_prfm_target target,
- enum aarch64_insn_prfm_policy policy)
-{
- u32 insn = aarch64_insn_get_prfm_value();
+ insn = aarch64_insn_encode_ldst_size(size, insn);
- insn = aarch64_insn_encode_ldst_size(AARCH64_INSN_SIZE_64, insn);
+ insn = aarch64_insn_encode_cas_order(order, insn);
- insn = aarch64_insn_encode_prfm_imm(type, target, policy, insn);
+ insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RT, insn,
+ result);
insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RN, insn,
- base);
+ address);
- return aarch64_insn_encode_immediate(AARCH64_INSN_IMM_12, insn, 0);
+ return aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RS, insn,
+ value);
}
+#endif
u32 aarch64_insn_gen_add_sub_imm(enum aarch64_insn_register dst,
enum aarch64_insn_register src,
@@ -1379,7 +1423,7 @@ static u32 aarch64_encode_immediate(u64 imm,
* Compute the rotation to get a continuous set of
* ones, with the first bit set at position 0
*/
- ror = fls(~imm);
+ ror = fls64(~imm);
}
/*
@@ -1456,3 +1500,72 @@ u32 aarch64_insn_gen_extr(enum aarch64_insn_variant variant,
insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RN, insn, Rn);
return aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RM, insn, Rm);
}
+
+static u32 __get_barrier_crm_val(enum aarch64_insn_mb_type type)
+{
+ switch (type) {
+ case AARCH64_INSN_MB_SY:
+ return 0xf;
+ case AARCH64_INSN_MB_ST:
+ return 0xe;
+ case AARCH64_INSN_MB_LD:
+ return 0xd;
+ case AARCH64_INSN_MB_ISH:
+ return 0xb;
+ case AARCH64_INSN_MB_ISHST:
+ return 0xa;
+ case AARCH64_INSN_MB_ISHLD:
+ return 0x9;
+ case AARCH64_INSN_MB_NSH:
+ return 0x7;
+ case AARCH64_INSN_MB_NSHST:
+ return 0x6;
+ case AARCH64_INSN_MB_NSHLD:
+ return 0x5;
+ default:
+ pr_err("%s: unknown barrier type %d\n", __func__, type);
+ return AARCH64_BREAK_FAULT;
+ }
+}
+
+u32 aarch64_insn_gen_dmb(enum aarch64_insn_mb_type type)
+{
+ u32 opt;
+ u32 insn;
+
+ opt = __get_barrier_crm_val(type);
+ if (opt == AARCH64_BREAK_FAULT)
+ return AARCH64_BREAK_FAULT;
+
+ insn = aarch64_insn_get_dmb_value();
+ insn &= ~GENMASK(11, 8);
+ insn |= (opt << 8);
+
+ return insn;
+}
+
+u32 aarch64_insn_gen_dsb(enum aarch64_insn_mb_type type)
+{
+ u32 opt, insn;
+
+ opt = __get_barrier_crm_val(type);
+ if (opt == AARCH64_BREAK_FAULT)
+ return AARCH64_BREAK_FAULT;
+
+ insn = aarch64_insn_get_dsb_base_value();
+ insn &= ~GENMASK(11, 8);
+ insn |= (opt << 8);
+
+ return insn;
+}
+
+u32 aarch64_insn_gen_mrs(enum aarch64_insn_register result,
+ enum aarch64_insn_system_register sysreg)
+{
+ u32 insn = aarch64_insn_get_mrs_value();
+
+ insn &= ~GENMASK(19, 0);
+ insn |= sysreg << 5;
+ return aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RT,
+ insn, result);
+}