qemu/target/arm/translate.h
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   1#ifndef TARGET_ARM_TRANSLATE_H
   2#define TARGET_ARM_TRANSLATE_H
   3
   4#include "exec/translator.h"
   5#include "internals.h"
   6
   7
   8/* internal defines */
   9typedef struct DisasContext {
  10    DisasContextBase base;
  11    const ARMISARegisters *isar;
  12
  13    /* The address of the current instruction being translated. */
  14    target_ulong pc_curr;
  15    target_ulong page_start;
  16    uint32_t insn;
  17    /* Nonzero if this instruction has been conditionally skipped.  */
  18    int condjmp;
  19    /* The label that will be jumped to when the instruction is skipped.  */
  20    TCGLabel *condlabel;
  21    /* Thumb-2 conditional execution bits.  */
  22    int condexec_mask;
  23    int condexec_cond;
  24    int thumb;
  25    int sctlr_b;
  26    MemOp be_data;
  27#if !defined(CONFIG_USER_ONLY)
  28    int user;
  29#endif
  30    ARMMMUIdx mmu_idx; /* MMU index to use for normal loads/stores */
  31    uint8_t tbii;      /* TBI1|TBI0 for insns */
  32    uint8_t tbid;      /* TBI1|TBI0 for data */
  33    bool ns;        /* Use non-secure CPREG bank on access */
  34    int fp_excp_el; /* FP exception EL or 0 if enabled */
  35    int sve_excp_el; /* SVE exception EL or 0 if enabled */
  36    int sve_len;     /* SVE vector length in bytes */
  37    /* Flag indicating that exceptions from secure mode are routed to EL3. */
  38    bool secure_routed_to_el3;
  39    bool vfp_enabled; /* FP enabled via FPSCR.EN */
  40    int vec_len;
  41    int vec_stride;
  42    bool v7m_handler_mode;
  43    bool v8m_secure; /* true if v8M and we're in Secure mode */
  44    bool v8m_stackcheck; /* true if we need to perform v8M stack limit checks */
  45    bool v8m_fpccr_s_wrong; /* true if v8M FPCCR.S != v8m_secure */
  46    bool v7m_new_fp_ctxt_needed; /* ASPEN set but no active FP context */
  47    bool v7m_lspact; /* FPCCR.LSPACT set */
  48    /* Immediate value in AArch32 SVC insn; must be set if is_jmp == DISAS_SWI
  49     * so that top level loop can generate correct syndrome information.
  50     */
  51    uint32_t svc_imm;
  52    int aarch64;
  53    int current_el;
  54    /* Debug target exception level for single-step exceptions */
  55    int debug_target_el;
  56    GHashTable *cp_regs;
  57    uint64_t features; /* CPU features bits */
  58    /* Because unallocated encodings generate different exception syndrome
  59     * information from traps due to FP being disabled, we can't do a single
  60     * "is fp access disabled" check at a high level in the decode tree.
  61     * To help in catching bugs where the access check was forgotten in some
  62     * code path, we set this flag when the access check is done, and assert
  63     * that it is set at the point where we actually touch the FP regs.
  64     */
  65    bool fp_access_checked;
  66    /* ARMv8 single-step state (this is distinct from the QEMU gdbstub
  67     * single-step support).
  68     */
  69    bool ss_active;
  70    bool pstate_ss;
  71    /* True if the insn just emitted was a load-exclusive instruction
  72     * (necessary for syndrome information for single step exceptions),
  73     * ie A64 LDX*, LDAX*, A32/T32 LDREX*, LDAEX*.
  74     */
  75    bool is_ldex;
  76    /* True if v8.3-PAuth is active.  */
  77    bool pauth_active;
  78    /* True with v8.5-BTI and SCTLR_ELx.BT* set.  */
  79    bool bt;
  80    /*
  81     * >= 0, a copy of PSTATE.BTYPE, which will be 0 without v8.5-BTI.
  82     *  < 0, set by the current instruction.
  83     */
  84    int8_t btype;
  85    /* True if this page is guarded.  */
  86    bool guarded_page;
  87    /* Bottom two bits of XScale c15_cpar coprocessor access control reg */
  88    int c15_cpar;
  89    /* TCG op of the current insn_start.  */
  90    TCGOp *insn_start;
  91#define TMP_A64_MAX 16
  92    int tmp_a64_count;
  93    TCGv_i64 tmp_a64[TMP_A64_MAX];
  94} DisasContext;
  95
  96typedef struct DisasCompare {
  97    TCGCond cond;
  98    TCGv_i32 value;
  99    bool value_global;
 100} DisasCompare;
 101
 102/* Share the TCG temporaries common between 32 and 64 bit modes.  */
 103extern TCGv_i32 cpu_NF, cpu_ZF, cpu_CF, cpu_VF;
 104extern TCGv_i64 cpu_exclusive_addr;
 105extern TCGv_i64 cpu_exclusive_val;
 106
 107static inline int arm_dc_feature(DisasContext *dc, int feature)
 108{
 109    return (dc->features & (1ULL << feature)) != 0;
 110}
 111
 112static inline int get_mem_index(DisasContext *s)
 113{
 114    return arm_to_core_mmu_idx(s->mmu_idx);
 115}
 116
 117/* Function used to determine the target exception EL when otherwise not known
 118 * or default.
 119 */
 120static inline int default_exception_el(DisasContext *s)
 121{
 122    /* If we are coming from secure EL0 in a system with a 32-bit EL3, then
 123     * there is no secure EL1, so we route exceptions to EL3.  Otherwise,
 124     * exceptions can only be routed to ELs above 1, so we target the higher of
 125     * 1 or the current EL.
 126     */
 127    return (s->mmu_idx == ARMMMUIdx_S1SE0 && s->secure_routed_to_el3)
 128            ? 3 : MAX(1, s->current_el);
 129}
 130
 131static inline void disas_set_insn_syndrome(DisasContext *s, uint32_t syn)
 132{
 133    /* We don't need to save all of the syndrome so we mask and shift
 134     * out unneeded bits to help the sleb128 encoder do a better job.
 135     */
 136    syn &= ARM_INSN_START_WORD2_MASK;
 137    syn >>= ARM_INSN_START_WORD2_SHIFT;
 138
 139    /* We check and clear insn_start_idx to catch multiple updates.  */
 140    assert(s->insn_start != NULL);
 141    tcg_set_insn_start_param(s->insn_start, 2, syn);
 142    s->insn_start = NULL;
 143}
 144
 145/* is_jmp field values */
 146#define DISAS_JUMP      DISAS_TARGET_0 /* only pc was modified dynamically */
 147#define DISAS_UPDATE    DISAS_TARGET_1 /* cpu state was modified dynamically */
 148/* These instructions trap after executing, so the A32/T32 decoder must
 149 * defer them until after the conditional execution state has been updated.
 150 * WFI also needs special handling when single-stepping.
 151 */
 152#define DISAS_WFI       DISAS_TARGET_2
 153#define DISAS_SWI       DISAS_TARGET_3
 154/* WFE */
 155#define DISAS_WFE       DISAS_TARGET_4
 156#define DISAS_HVC       DISAS_TARGET_5
 157#define DISAS_SMC       DISAS_TARGET_6
 158#define DISAS_YIELD     DISAS_TARGET_7
 159/* M profile branch which might be an exception return (and so needs
 160 * custom end-of-TB code)
 161 */
 162#define DISAS_BX_EXCRET DISAS_TARGET_8
 163/* For instructions which want an immediate exit to the main loop,
 164 * as opposed to attempting to use lookup_and_goto_ptr. Unlike
 165 * DISAS_UPDATE this doesn't write the PC on exiting the translation
 166 * loop so you need to ensure something (gen_a64_set_pc_im or runtime
 167 * helper) has done so before we reach return from cpu_tb_exec.
 168 */
 169#define DISAS_EXIT      DISAS_TARGET_9
 170
 171#ifdef TARGET_AARCH64
 172void a64_translate_init(void);
 173void gen_a64_set_pc_im(uint64_t val);
 174extern const TranslatorOps aarch64_translator_ops;
 175#else
 176static inline void a64_translate_init(void)
 177{
 178}
 179
 180static inline void gen_a64_set_pc_im(uint64_t val)
 181{
 182}
 183#endif
 184
 185void arm_test_cc(DisasCompare *cmp, int cc);
 186void arm_free_cc(DisasCompare *cmp);
 187void arm_jump_cc(DisasCompare *cmp, TCGLabel *label);
 188void arm_gen_test_cc(int cc, TCGLabel *label);
 189
 190/* Return state of Alternate Half-precision flag, caller frees result */
 191static inline TCGv_i32 get_ahp_flag(void)
 192{
 193    TCGv_i32 ret = tcg_temp_new_i32();
 194
 195    tcg_gen_ld_i32(ret, cpu_env,
 196                   offsetof(CPUARMState, vfp.xregs[ARM_VFP_FPSCR]));
 197    tcg_gen_extract_i32(ret, ret, 26, 1);
 198
 199    return ret;
 200}
 201
 202/* Set bits within PSTATE.  */
 203static inline void set_pstate_bits(uint32_t bits)
 204{
 205    TCGv_i32 p = tcg_temp_new_i32();
 206
 207    tcg_debug_assert(!(bits & CACHED_PSTATE_BITS));
 208
 209    tcg_gen_ld_i32(p, cpu_env, offsetof(CPUARMState, pstate));
 210    tcg_gen_ori_i32(p, p, bits);
 211    tcg_gen_st_i32(p, cpu_env, offsetof(CPUARMState, pstate));
 212    tcg_temp_free_i32(p);
 213}
 214
 215/* Clear bits within PSTATE.  */
 216static inline void clear_pstate_bits(uint32_t bits)
 217{
 218    TCGv_i32 p = tcg_temp_new_i32();
 219
 220    tcg_debug_assert(!(bits & CACHED_PSTATE_BITS));
 221
 222    tcg_gen_ld_i32(p, cpu_env, offsetof(CPUARMState, pstate));
 223    tcg_gen_andi_i32(p, p, ~bits);
 224    tcg_gen_st_i32(p, cpu_env, offsetof(CPUARMState, pstate));
 225    tcg_temp_free_i32(p);
 226}
 227
 228/* If the singlestep state is Active-not-pending, advance to Active-pending. */
 229static inline void gen_ss_advance(DisasContext *s)
 230{
 231    if (s->ss_active) {
 232        s->pstate_ss = 0;
 233        clear_pstate_bits(PSTATE_SS);
 234    }
 235}
 236
 237static inline void gen_exception(int excp, uint32_t syndrome,
 238                                 uint32_t target_el)
 239{
 240    TCGv_i32 tcg_excp = tcg_const_i32(excp);
 241    TCGv_i32 tcg_syn = tcg_const_i32(syndrome);
 242    TCGv_i32 tcg_el = tcg_const_i32(target_el);
 243
 244    gen_helper_exception_with_syndrome(cpu_env, tcg_excp,
 245                                       tcg_syn, tcg_el);
 246
 247    tcg_temp_free_i32(tcg_el);
 248    tcg_temp_free_i32(tcg_syn);
 249    tcg_temp_free_i32(tcg_excp);
 250}
 251
 252/* Generate an architectural singlestep exception */
 253static inline void gen_swstep_exception(DisasContext *s, int isv, int ex)
 254{
 255    bool same_el = (s->debug_target_el == s->current_el);
 256
 257    /*
 258     * If singlestep is targeting a lower EL than the current one,
 259     * then s->ss_active must be false and we can never get here.
 260     */
 261    assert(s->debug_target_el >= s->current_el);
 262
 263    gen_exception(EXCP_UDEF, syn_swstep(same_el, isv, ex), s->debug_target_el);
 264}
 265
 266/*
 267 * Given a VFP floating point constant encoded into an 8 bit immediate in an
 268 * instruction, expand it to the actual constant value of the specified
 269 * size, as per the VFPExpandImm() pseudocode in the Arm ARM.
 270 */
 271uint64_t vfp_expand_imm(int size, uint8_t imm8);
 272
 273/* Vector operations shared between ARM and AArch64.  */
 274extern const GVecGen3 mla_op[4];
 275extern const GVecGen3 mls_op[4];
 276extern const GVecGen3 cmtst_op[4];
 277extern const GVecGen2i ssra_op[4];
 278extern const GVecGen2i usra_op[4];
 279extern const GVecGen2i sri_op[4];
 280extern const GVecGen2i sli_op[4];
 281extern const GVecGen4 uqadd_op[4];
 282extern const GVecGen4 sqadd_op[4];
 283extern const GVecGen4 uqsub_op[4];
 284extern const GVecGen4 sqsub_op[4];
 285void gen_cmtst_i64(TCGv_i64 d, TCGv_i64 a, TCGv_i64 b);
 286
 287/*
 288 * Forward to the isar_feature_* tests given a DisasContext pointer.
 289 */
 290#define dc_isar_feature(name, ctx) \
 291    ({ DisasContext *ctx_ = (ctx); isar_feature_##name(ctx_->isar); })
 292
 293#endif /* TARGET_ARM_TRANSLATE_H */
 294