1 #ifndef TARGET_ARM_TRANSLATE_H
2 #define TARGET_ARM_TRANSLATE_H
4 #include "exec/translator.h"
9 typedef struct DisasContext
{
10 DisasContextBase base
;
11 const ARMISARegisters
*isar
;
13 /* The address of the current instruction being translated. */
15 target_ulong page_start
;
17 /* Nonzero if this instruction has been conditionally skipped. */
19 /* The label that will be jumped to when the instruction is skipped. */
21 /* Thumb-2 conditional execution bits. */
24 /* M-profile ECI/ICI exception-continuable instruction state */
27 * trans_ functions for insns which are continuable should set this true
28 * after decode (ie after any UNDEF checks)
31 /* TCG op to rewind to if this turns out to be an invalid ECI state */
32 TCGOp
*insn_eci_rewind
;
36 #if !defined(CONFIG_USER_ONLY)
39 ARMMMUIdx mmu_idx
; /* MMU index to use for normal loads/stores */
40 uint8_t tbii
; /* TBI1|TBI0 for insns */
41 uint8_t tbid
; /* TBI1|TBI0 for data */
42 uint8_t tcma
; /* TCMA1|TCMA0 for MTE */
43 bool ns
; /* Use non-secure CPREG bank on access */
44 int fp_excp_el
; /* FP exception EL or 0 if enabled */
45 int sve_excp_el
; /* SVE exception EL or 0 if enabled */
46 int sve_len
; /* SVE vector length in bytes */
47 /* Flag indicating that exceptions from secure mode are routed to EL3. */
48 bool secure_routed_to_el3
;
49 bool vfp_enabled
; /* FP enabled via FPSCR.EN */
52 bool v7m_handler_mode
;
53 bool v8m_secure
; /* true if v8M and we're in Secure mode */
54 bool v8m_stackcheck
; /* true if we need to perform v8M stack limit checks */
55 bool v8m_fpccr_s_wrong
; /* true if v8M FPCCR.S != v8m_secure */
56 bool v7m_new_fp_ctxt_needed
; /* ASPEN set but no active FP context */
57 bool v7m_lspact
; /* FPCCR.LSPACT set */
58 /* Immediate value in AArch32 SVC insn; must be set if is_jmp == DISAS_SWI
59 * so that top level loop can generate correct syndrome information.
64 /* Debug target exception level for single-step exceptions */
67 uint64_t features
; /* CPU features bits */
68 /* Because unallocated encodings generate different exception syndrome
69 * information from traps due to FP being disabled, we can't do a single
70 * "is fp access disabled" check at a high level in the decode tree.
71 * To help in catching bugs where the access check was forgotten in some
72 * code path, we set this flag when the access check is done, and assert
73 * that it is set at the point where we actually touch the FP regs.
75 bool fp_access_checked
;
76 bool sve_access_checked
;
77 /* ARMv8 single-step state (this is distinct from the QEMU gdbstub
78 * single-step support).
82 /* True if the insn just emitted was a load-exclusive instruction
83 * (necessary for syndrome information for single step exceptions),
84 * ie A64 LDX*, LDAX*, A32/T32 LDREX*, LDAEX*.
87 /* True if AccType_UNPRIV should be used for LDTR et al */
89 /* True if v8.3-PAuth is active. */
91 /* True if v8.5-MTE access to tags is enabled. */
93 /* True if v8.5-MTE tag checks affect the PE; index with is_unpriv. */
95 /* True with v8.5-BTI and SCTLR_ELx.BT* set. */
97 /* True if any CP15 access is trapped by HSTR_EL2 */
99 /* True if memory operations require alignment */
102 * >= 0, a copy of PSTATE.BTYPE, which will be 0 without v8.5-BTI.
103 * < 0, set by the current instruction.
106 /* A copy of cpu->dcz_blocksize. */
107 uint8_t dcz_blocksize
;
108 /* True if this page is guarded. */
110 /* Bottom two bits of XScale c15_cpar coprocessor access control reg */
112 /* TCG op of the current insn_start. */
114 #define TMP_A64_MAX 16
116 TCGv_i64 tmp_a64
[TMP_A64_MAX
];
119 typedef struct DisasCompare
{
125 /* Share the TCG temporaries common between 32 and 64 bit modes. */
126 extern TCGv_i32 cpu_NF
, cpu_ZF
, cpu_CF
, cpu_VF
;
127 extern TCGv_i64 cpu_exclusive_addr
;
128 extern TCGv_i64 cpu_exclusive_val
;
131 * Constant expanders for the decoders.
134 static inline int negate(DisasContext
*s
, int x
)
139 static inline int plus_1(DisasContext
*s
, int x
)
144 static inline int plus_2(DisasContext
*s
, int x
)
149 static inline int times_2(DisasContext
*s
, int x
)
154 static inline int times_4(DisasContext
*s
, int x
)
159 static inline int times_2_plus_1(DisasContext
*s
, int x
)
164 static inline int rsub_64(DisasContext
*s
, int x
)
169 static inline int rsub_32(DisasContext
*s
, int x
)
174 static inline int rsub_16(DisasContext
*s
, int x
)
179 static inline int rsub_8(DisasContext
*s
, int x
)
184 static inline int neon_3same_fp_size(DisasContext
*s
, int x
)
186 /* Convert 0==fp32, 1==fp16 into a MO_* value */
190 static inline int arm_dc_feature(DisasContext
*dc
, int feature
)
192 return (dc
->features
& (1ULL << feature
)) != 0;
195 static inline int get_mem_index(DisasContext
*s
)
197 return arm_to_core_mmu_idx(s
->mmu_idx
);
200 /* Function used to determine the target exception EL when otherwise not known
203 static inline int default_exception_el(DisasContext
*s
)
205 /* If we are coming from secure EL0 in a system with a 32-bit EL3, then
206 * there is no secure EL1, so we route exceptions to EL3. Otherwise,
207 * exceptions can only be routed to ELs above 1, so we target the higher of
208 * 1 or the current EL.
210 return (s
->mmu_idx
== ARMMMUIdx_SE10_0
&& s
->secure_routed_to_el3
)
211 ? 3 : MAX(1, s
->current_el
);
214 static inline void disas_set_insn_syndrome(DisasContext
*s
, uint32_t syn
)
216 /* We don't need to save all of the syndrome so we mask and shift
217 * out unneeded bits to help the sleb128 encoder do a better job.
219 syn
&= ARM_INSN_START_WORD2_MASK
;
220 syn
>>= ARM_INSN_START_WORD2_SHIFT
;
222 /* We check and clear insn_start_idx to catch multiple updates. */
223 assert(s
->insn_start
!= NULL
);
224 tcg_set_insn_start_param(s
->insn_start
, 2, syn
);
225 s
->insn_start
= NULL
;
228 /* is_jmp field values */
229 #define DISAS_JUMP DISAS_TARGET_0 /* only pc was modified dynamically */
230 /* CPU state was modified dynamically; exit to main loop for interrupts. */
231 #define DISAS_UPDATE_EXIT DISAS_TARGET_1
232 /* These instructions trap after executing, so the A32/T32 decoder must
233 * defer them until after the conditional execution state has been updated.
234 * WFI also needs special handling when single-stepping.
236 #define DISAS_WFI DISAS_TARGET_2
237 #define DISAS_SWI DISAS_TARGET_3
239 #define DISAS_WFE DISAS_TARGET_4
240 #define DISAS_HVC DISAS_TARGET_5
241 #define DISAS_SMC DISAS_TARGET_6
242 #define DISAS_YIELD DISAS_TARGET_7
243 /* M profile branch which might be an exception return (and so needs
244 * custom end-of-TB code)
246 #define DISAS_BX_EXCRET DISAS_TARGET_8
248 * For instructions which want an immediate exit to the main loop, as opposed
249 * to attempting to use lookup_and_goto_ptr. Unlike DISAS_UPDATE_EXIT, this
250 * doesn't write the PC on exiting the translation loop so you need to ensure
251 * something (gen_a64_set_pc_im or runtime helper) has done so before we reach
252 * return from cpu_tb_exec.
254 #define DISAS_EXIT DISAS_TARGET_9
255 /* CPU state was modified dynamically; no need to exit, but do not chain. */
256 #define DISAS_UPDATE_NOCHAIN DISAS_TARGET_10
258 #ifdef TARGET_AARCH64
259 void a64_translate_init(void);
260 void gen_a64_set_pc_im(uint64_t val
);
261 extern const TranslatorOps aarch64_translator_ops
;
263 static inline void a64_translate_init(void)
267 static inline void gen_a64_set_pc_im(uint64_t val
)
272 void arm_test_cc(DisasCompare
*cmp
, int cc
);
273 void arm_free_cc(DisasCompare
*cmp
);
274 void arm_jump_cc(DisasCompare
*cmp
, TCGLabel
*label
);
275 void arm_gen_test_cc(int cc
, TCGLabel
*label
);
276 MemOp
pow2_align(unsigned i
);
277 void unallocated_encoding(DisasContext
*s
);
278 void gen_exception_insn(DisasContext
*s
, uint64_t pc
, int excp
,
279 uint32_t syn
, uint32_t target_el
);
281 /* Return state of Alternate Half-precision flag, caller frees result */
282 static inline TCGv_i32
get_ahp_flag(void)
284 TCGv_i32 ret
= tcg_temp_new_i32();
286 tcg_gen_ld_i32(ret
, cpu_env
,
287 offsetof(CPUARMState
, vfp
.xregs
[ARM_VFP_FPSCR
]));
288 tcg_gen_extract_i32(ret
, ret
, 26, 1);
293 /* Set bits within PSTATE. */
294 static inline void set_pstate_bits(uint32_t bits
)
296 TCGv_i32 p
= tcg_temp_new_i32();
298 tcg_debug_assert(!(bits
& CACHED_PSTATE_BITS
));
300 tcg_gen_ld_i32(p
, cpu_env
, offsetof(CPUARMState
, pstate
));
301 tcg_gen_ori_i32(p
, p
, bits
);
302 tcg_gen_st_i32(p
, cpu_env
, offsetof(CPUARMState
, pstate
));
303 tcg_temp_free_i32(p
);
306 /* Clear bits within PSTATE. */
307 static inline void clear_pstate_bits(uint32_t bits
)
309 TCGv_i32 p
= tcg_temp_new_i32();
311 tcg_debug_assert(!(bits
& CACHED_PSTATE_BITS
));
313 tcg_gen_ld_i32(p
, cpu_env
, offsetof(CPUARMState
, pstate
));
314 tcg_gen_andi_i32(p
, p
, ~bits
);
315 tcg_gen_st_i32(p
, cpu_env
, offsetof(CPUARMState
, pstate
));
316 tcg_temp_free_i32(p
);
319 /* If the singlestep state is Active-not-pending, advance to Active-pending. */
320 static inline void gen_ss_advance(DisasContext
*s
)
324 clear_pstate_bits(PSTATE_SS
);
328 static inline void gen_exception(int excp
, uint32_t syndrome
,
331 TCGv_i32 tcg_excp
= tcg_const_i32(excp
);
332 TCGv_i32 tcg_syn
= tcg_const_i32(syndrome
);
333 TCGv_i32 tcg_el
= tcg_const_i32(target_el
);
335 gen_helper_exception_with_syndrome(cpu_env
, tcg_excp
,
338 tcg_temp_free_i32(tcg_el
);
339 tcg_temp_free_i32(tcg_syn
);
340 tcg_temp_free_i32(tcg_excp
);
343 /* Generate an architectural singlestep exception */
344 static inline void gen_swstep_exception(DisasContext
*s
, int isv
, int ex
)
346 bool same_el
= (s
->debug_target_el
== s
->current_el
);
349 * If singlestep is targeting a lower EL than the current one,
350 * then s->ss_active must be false and we can never get here.
352 assert(s
->debug_target_el
>= s
->current_el
);
354 gen_exception(EXCP_UDEF
, syn_swstep(same_el
, isv
, ex
), s
->debug_target_el
);
358 * Given a VFP floating point constant encoded into an 8 bit immediate in an
359 * instruction, expand it to the actual constant value of the specified
360 * size, as per the VFPExpandImm() pseudocode in the Arm ARM.
362 uint64_t vfp_expand_imm(int size
, uint8_t imm8
);
364 /* Vector operations shared between ARM and AArch64. */
365 void gen_gvec_ceq0(unsigned vece
, uint32_t rd_ofs
, uint32_t rm_ofs
,
366 uint32_t opr_sz
, uint32_t max_sz
);
367 void gen_gvec_clt0(unsigned vece
, uint32_t rd_ofs
, uint32_t rm_ofs
,
368 uint32_t opr_sz
, uint32_t max_sz
);
369 void gen_gvec_cgt0(unsigned vece
, uint32_t rd_ofs
, uint32_t rm_ofs
,
370 uint32_t opr_sz
, uint32_t max_sz
);
371 void gen_gvec_cle0(unsigned vece
, uint32_t rd_ofs
, uint32_t rm_ofs
,
372 uint32_t opr_sz
, uint32_t max_sz
);
373 void gen_gvec_cge0(unsigned vece
, uint32_t rd_ofs
, uint32_t rm_ofs
,
374 uint32_t opr_sz
, uint32_t max_sz
);
376 void gen_gvec_mla(unsigned vece
, uint32_t rd_ofs
, uint32_t rn_ofs
,
377 uint32_t rm_ofs
, uint32_t opr_sz
, uint32_t max_sz
);
378 void gen_gvec_mls(unsigned vece
, uint32_t rd_ofs
, uint32_t rn_ofs
,
379 uint32_t rm_ofs
, uint32_t opr_sz
, uint32_t max_sz
);
381 void gen_gvec_cmtst(unsigned vece
, uint32_t rd_ofs
, uint32_t rn_ofs
,
382 uint32_t rm_ofs
, uint32_t opr_sz
, uint32_t max_sz
);
383 void gen_gvec_sshl(unsigned vece
, uint32_t rd_ofs
, uint32_t rn_ofs
,
384 uint32_t rm_ofs
, uint32_t opr_sz
, uint32_t max_sz
);
385 void gen_gvec_ushl(unsigned vece
, uint32_t rd_ofs
, uint32_t rn_ofs
,
386 uint32_t rm_ofs
, uint32_t opr_sz
, uint32_t max_sz
);
388 void gen_cmtst_i64(TCGv_i64 d
, TCGv_i64 a
, TCGv_i64 b
);
389 void gen_ushl_i32(TCGv_i32 d
, TCGv_i32 a
, TCGv_i32 b
);
390 void gen_sshl_i32(TCGv_i32 d
, TCGv_i32 a
, TCGv_i32 b
);
391 void gen_ushl_i64(TCGv_i64 d
, TCGv_i64 a
, TCGv_i64 b
);
392 void gen_sshl_i64(TCGv_i64 d
, TCGv_i64 a
, TCGv_i64 b
);
394 void gen_gvec_uqadd_qc(unsigned vece
, uint32_t rd_ofs
, uint32_t rn_ofs
,
395 uint32_t rm_ofs
, uint32_t opr_sz
, uint32_t max_sz
);
396 void gen_gvec_sqadd_qc(unsigned vece
, uint32_t rd_ofs
, uint32_t rn_ofs
,
397 uint32_t rm_ofs
, uint32_t opr_sz
, uint32_t max_sz
);
398 void gen_gvec_uqsub_qc(unsigned vece
, uint32_t rd_ofs
, uint32_t rn_ofs
,
399 uint32_t rm_ofs
, uint32_t opr_sz
, uint32_t max_sz
);
400 void gen_gvec_sqsub_qc(unsigned vece
, uint32_t rd_ofs
, uint32_t rn_ofs
,
401 uint32_t rm_ofs
, uint32_t opr_sz
, uint32_t max_sz
);
403 void gen_gvec_ssra(unsigned vece
, uint32_t rd_ofs
, uint32_t rm_ofs
,
404 int64_t shift
, uint32_t opr_sz
, uint32_t max_sz
);
405 void gen_gvec_usra(unsigned vece
, uint32_t rd_ofs
, uint32_t rm_ofs
,
406 int64_t shift
, uint32_t opr_sz
, uint32_t max_sz
);
408 void gen_gvec_srshr(unsigned vece
, uint32_t rd_ofs
, uint32_t rm_ofs
,
409 int64_t shift
, uint32_t opr_sz
, uint32_t max_sz
);
410 void gen_gvec_urshr(unsigned vece
, uint32_t rd_ofs
, uint32_t rm_ofs
,
411 int64_t shift
, uint32_t opr_sz
, uint32_t max_sz
);
412 void gen_gvec_srsra(unsigned vece
, uint32_t rd_ofs
, uint32_t rm_ofs
,
413 int64_t shift
, uint32_t opr_sz
, uint32_t max_sz
);
414 void gen_gvec_ursra(unsigned vece
, uint32_t rd_ofs
, uint32_t rm_ofs
,
415 int64_t shift
, uint32_t opr_sz
, uint32_t max_sz
);
417 void gen_gvec_sri(unsigned vece
, uint32_t rd_ofs
, uint32_t rm_ofs
,
418 int64_t shift
, uint32_t opr_sz
, uint32_t max_sz
);
419 void gen_gvec_sli(unsigned vece
, uint32_t rd_ofs
, uint32_t rm_ofs
,
420 int64_t shift
, uint32_t opr_sz
, uint32_t max_sz
);
422 void gen_gvec_sqrdmlah_qc(unsigned vece
, uint32_t rd_ofs
, uint32_t rn_ofs
,
423 uint32_t rm_ofs
, uint32_t opr_sz
, uint32_t max_sz
);
424 void gen_gvec_sqrdmlsh_qc(unsigned vece
, uint32_t rd_ofs
, uint32_t rn_ofs
,
425 uint32_t rm_ofs
, uint32_t opr_sz
, uint32_t max_sz
);
427 void gen_gvec_sabd(unsigned vece
, uint32_t rd_ofs
, uint32_t rn_ofs
,
428 uint32_t rm_ofs
, uint32_t opr_sz
, uint32_t max_sz
);
429 void gen_gvec_uabd(unsigned vece
, uint32_t rd_ofs
, uint32_t rn_ofs
,
430 uint32_t rm_ofs
, uint32_t opr_sz
, uint32_t max_sz
);
432 void gen_gvec_saba(unsigned vece
, uint32_t rd_ofs
, uint32_t rn_ofs
,
433 uint32_t rm_ofs
, uint32_t opr_sz
, uint32_t max_sz
);
434 void gen_gvec_uaba(unsigned vece
, uint32_t rd_ofs
, uint32_t rn_ofs
,
435 uint32_t rm_ofs
, uint32_t opr_sz
, uint32_t max_sz
);
438 * Forward to the isar_feature_* tests given a DisasContext pointer.
440 #define dc_isar_feature(name, ctx) \
441 ({ DisasContext *ctx_ = (ctx); isar_feature_##name(ctx_->isar); })
443 /* Note that the gvec expanders operate on offsets + sizes. */
444 typedef void GVecGen2Fn(unsigned, uint32_t, uint32_t, uint32_t, uint32_t);
445 typedef void GVecGen2iFn(unsigned, uint32_t, uint32_t, int64_t,
447 typedef void GVecGen3Fn(unsigned, uint32_t, uint32_t,
448 uint32_t, uint32_t, uint32_t);
449 typedef void GVecGen4Fn(unsigned, uint32_t, uint32_t, uint32_t,
450 uint32_t, uint32_t, uint32_t);
452 /* Function prototype for gen_ functions for calling Neon helpers */
453 typedef void NeonGenOneOpFn(TCGv_i32
, TCGv_i32
);
454 typedef void NeonGenOneOpEnvFn(TCGv_i32
, TCGv_ptr
, TCGv_i32
);
455 typedef void NeonGenTwoOpFn(TCGv_i32
, TCGv_i32
, TCGv_i32
);
456 typedef void NeonGenTwoOpEnvFn(TCGv_i32
, TCGv_ptr
, TCGv_i32
, TCGv_i32
);
457 typedef void NeonGenThreeOpEnvFn(TCGv_i32
, TCGv_env
, TCGv_i32
,
459 typedef void NeonGenTwo64OpFn(TCGv_i64
, TCGv_i64
, TCGv_i64
);
460 typedef void NeonGenTwo64OpEnvFn(TCGv_i64
, TCGv_ptr
, TCGv_i64
, TCGv_i64
);
461 typedef void NeonGenNarrowFn(TCGv_i32
, TCGv_i64
);
462 typedef void NeonGenNarrowEnvFn(TCGv_i32
, TCGv_ptr
, TCGv_i64
);
463 typedef void NeonGenWidenFn(TCGv_i64
, TCGv_i32
);
464 typedef void NeonGenTwoOpWidenFn(TCGv_i64
, TCGv_i32
, TCGv_i32
);
465 typedef void NeonGenOneSingleOpFn(TCGv_i32
, TCGv_i32
, TCGv_ptr
);
466 typedef void NeonGenTwoSingleOpFn(TCGv_i32
, TCGv_i32
, TCGv_i32
, TCGv_ptr
);
467 typedef void NeonGenTwoDoubleOpFn(TCGv_i64
, TCGv_i64
, TCGv_i64
, TCGv_ptr
);
468 typedef void NeonGenOne64OpFn(TCGv_i64
, TCGv_i64
);
469 typedef void CryptoTwoOpFn(TCGv_ptr
, TCGv_ptr
);
470 typedef void CryptoThreeOpIntFn(TCGv_ptr
, TCGv_ptr
, TCGv_i32
);
471 typedef void CryptoThreeOpFn(TCGv_ptr
, TCGv_ptr
, TCGv_ptr
);
472 typedef void AtomicThreeOpFn(TCGv_i64
, TCGv_i64
, TCGv_i64
, TCGArg
, MemOp
);
473 typedef void WideShiftImmFn(TCGv_i64
, TCGv_i64
, int64_t shift
);
474 typedef void WideShiftFn(TCGv_i64
, TCGv_ptr
, TCGv_i64
, TCGv_i32
);
475 typedef void ShiftImmFn(TCGv_i32
, TCGv_i32
, int32_t shift
);
476 typedef void ShiftFn(TCGv_i32
, TCGv_ptr
, TCGv_i32
, TCGv_i32
);
479 * arm_tbflags_from_tb:
480 * @tb: the TranslationBlock
482 * Extract the flag values from @tb.
484 static inline CPUARMTBFlags
arm_tbflags_from_tb(const TranslationBlock
*tb
)
486 return (CPUARMTBFlags
){ tb
->flags
, tb
->cs_base
};
490 * Enum for argument to fpstatus_ptr().
492 typedef enum ARMFPStatusFlavour
{
497 } ARMFPStatusFlavour
;
500 * fpstatus_ptr: return TCGv_ptr to the specified fp_status field
502 * We have multiple softfloat float_status fields in the Arm CPU state struct
503 * (see the comment in cpu.h for details). Return a TCGv_ptr which has
504 * been set up to point to the requested field in the CPU state struct.
508 * for non-FP16 operations controlled by the FPCR
510 * for operations controlled by the FPCR where FPCR.FZ16 is to be used
512 * for A32/T32 Neon operations using the "standard FPSCR value"
514 * as FPST_STD, but where FPCR.FZ16 is to be used
516 static inline TCGv_ptr
fpstatus_ptr(ARMFPStatusFlavour flavour
)
518 TCGv_ptr statusptr
= tcg_temp_new_ptr();
523 offset
= offsetof(CPUARMState
, vfp
.fp_status
);
526 offset
= offsetof(CPUARMState
, vfp
.fp_status_f16
);
529 offset
= offsetof(CPUARMState
, vfp
.standard_fp_status
);
532 offset
= offsetof(CPUARMState
, vfp
.standard_fp_status_f16
);
535 g_assert_not_reached();
537 tcg_gen_addi_ptr(statusptr
, cpu_env
, offset
);
544 * @opc: size+sign+align of the memory operation
546 * Build the complete MemOp for a memory operation, including alignment
549 * If (op & MO_AMASK) then the operation already contains the required
550 * alignment, e.g. for AccType_ATOMIC. Otherwise, this an optionally
551 * unaligned operation, e.g. for AccType_NORMAL.
553 * In the latter case, there are configuration bits that require alignment,
554 * and this is applied here. Note that there is no way to indicate that
555 * no alignment should ever be enforced; this must be handled manually.
557 static inline MemOp
finalize_memop(DisasContext
*s
, MemOp opc
)
559 if (s
->align_mem
&& !(opc
& MO_AMASK
)) {
562 return opc
| s
->be_data
;
566 * asimd_imm_const: Expand an encoded SIMD constant value
568 * Expand a SIMD constant value. This is essentially the pseudocode
569 * AdvSIMDExpandImm, except that we also perform the boolean NOT needed for
570 * VMVN and VBIC (when cmode < 14 && op == 1).
572 * The combination cmode == 15 op == 1 is a reserved encoding for AArch32;
573 * callers must catch this; we return the 64-bit constant value defined
576 * cmode = 2,3,4,5,6,7,10,11,12,13 imm=0 was UNPREDICTABLE in v7A but
577 * is either not unpredictable or merely CONSTRAINED UNPREDICTABLE in v8A;
578 * we produce an immediate constant value of 0 in these cases.
580 uint64_t asimd_imm_const(uint32_t imm
, int cmode
, int op
);
582 #endif /* TARGET_ARM_TRANSLATE_H */