xref: /qemu/include/tcg/tcg.h (revision 84615a19)
1 /*
2  * Tiny Code Generator for QEMU
3  *
4  * Copyright (c) 2008 Fabrice Bellard
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 
25 #ifndef TCG_H
26 #define TCG_H
27 
28 #include "cpu.h"
29 #include "exec/memop.h"
30 #include "exec/memopidx.h"
31 #include "qemu/bitops.h"
32 #include "qemu/plugin.h"
33 #include "qemu/queue.h"
34 #include "tcg/tcg-mo.h"
35 #include "tcg-target.h"
36 #include "tcg/tcg-cond.h"
37 
38 /* XXX: make safe guess about sizes */
39 #define MAX_OP_PER_INSTR 266
40 
41 #define MAX_CALL_IARGS  7
42 
43 #define CPU_TEMP_BUF_NLONGS 128
44 #define TCG_STATIC_FRAME_SIZE  (CPU_TEMP_BUF_NLONGS * sizeof(long))
45 
46 /* Default target word size to pointer size.  */
47 #ifndef TCG_TARGET_REG_BITS
48 # if UINTPTR_MAX == UINT32_MAX
49 #  define TCG_TARGET_REG_BITS 32
50 # elif UINTPTR_MAX == UINT64_MAX
51 #  define TCG_TARGET_REG_BITS 64
52 # else
53 #  error Unknown pointer size for tcg target
54 # endif
55 #endif
56 
57 #if TCG_TARGET_REG_BITS == 32
58 typedef int32_t tcg_target_long;
59 typedef uint32_t tcg_target_ulong;
60 #define TCG_PRIlx PRIx32
61 #define TCG_PRIld PRId32
62 #elif TCG_TARGET_REG_BITS == 64
63 typedef int64_t tcg_target_long;
64 typedef uint64_t tcg_target_ulong;
65 #define TCG_PRIlx PRIx64
66 #define TCG_PRIld PRId64
67 #else
68 #error unsupported
69 #endif
70 
71 /* Oversized TCG guests make things like MTTCG hard
72  * as we can't use atomics for cputlb updates.
73  */
74 #if TARGET_LONG_BITS > TCG_TARGET_REG_BITS
75 #define TCG_OVERSIZED_GUEST 1
76 #else
77 #define TCG_OVERSIZED_GUEST 0
78 #endif
79 
80 #if TCG_TARGET_NB_REGS <= 32
81 typedef uint32_t TCGRegSet;
82 #elif TCG_TARGET_NB_REGS <= 64
83 typedef uint64_t TCGRegSet;
84 #else
85 #error unsupported
86 #endif
87 
88 #if TCG_TARGET_REG_BITS == 32
89 /* Turn some undef macros into false macros.  */
90 #define TCG_TARGET_HAS_extrl_i64_i32    0
91 #define TCG_TARGET_HAS_extrh_i64_i32    0
92 #define TCG_TARGET_HAS_div_i64          0
93 #define TCG_TARGET_HAS_rem_i64          0
94 #define TCG_TARGET_HAS_div2_i64         0
95 #define TCG_TARGET_HAS_rot_i64          0
96 #define TCG_TARGET_HAS_ext8s_i64        0
97 #define TCG_TARGET_HAS_ext16s_i64       0
98 #define TCG_TARGET_HAS_ext32s_i64       0
99 #define TCG_TARGET_HAS_ext8u_i64        0
100 #define TCG_TARGET_HAS_ext16u_i64       0
101 #define TCG_TARGET_HAS_ext32u_i64       0
102 #define TCG_TARGET_HAS_bswap16_i64      0
103 #define TCG_TARGET_HAS_bswap32_i64      0
104 #define TCG_TARGET_HAS_bswap64_i64      0
105 #define TCG_TARGET_HAS_neg_i64          0
106 #define TCG_TARGET_HAS_not_i64          0
107 #define TCG_TARGET_HAS_andc_i64         0
108 #define TCG_TARGET_HAS_orc_i64          0
109 #define TCG_TARGET_HAS_eqv_i64          0
110 #define TCG_TARGET_HAS_nand_i64         0
111 #define TCG_TARGET_HAS_nor_i64          0
112 #define TCG_TARGET_HAS_clz_i64          0
113 #define TCG_TARGET_HAS_ctz_i64          0
114 #define TCG_TARGET_HAS_ctpop_i64        0
115 #define TCG_TARGET_HAS_deposit_i64      0
116 #define TCG_TARGET_HAS_extract_i64      0
117 #define TCG_TARGET_HAS_sextract_i64     0
118 #define TCG_TARGET_HAS_extract2_i64     0
119 #define TCG_TARGET_HAS_movcond_i64      0
120 #define TCG_TARGET_HAS_add2_i64         0
121 #define TCG_TARGET_HAS_sub2_i64         0
122 #define TCG_TARGET_HAS_mulu2_i64        0
123 #define TCG_TARGET_HAS_muls2_i64        0
124 #define TCG_TARGET_HAS_muluh_i64        0
125 #define TCG_TARGET_HAS_mulsh_i64        0
126 /* Turn some undef macros into true macros.  */
127 #define TCG_TARGET_HAS_add2_i32         1
128 #define TCG_TARGET_HAS_sub2_i32         1
129 #endif
130 
131 #ifndef TCG_TARGET_deposit_i32_valid
132 #define TCG_TARGET_deposit_i32_valid(ofs, len) 1
133 #endif
134 #ifndef TCG_TARGET_deposit_i64_valid
135 #define TCG_TARGET_deposit_i64_valid(ofs, len) 1
136 #endif
137 #ifndef TCG_TARGET_extract_i32_valid
138 #define TCG_TARGET_extract_i32_valid(ofs, len) 1
139 #endif
140 #ifndef TCG_TARGET_extract_i64_valid
141 #define TCG_TARGET_extract_i64_valid(ofs, len) 1
142 #endif
143 
144 /* Only one of DIV or DIV2 should be defined.  */
145 #if defined(TCG_TARGET_HAS_div_i32)
146 #define TCG_TARGET_HAS_div2_i32         0
147 #elif defined(TCG_TARGET_HAS_div2_i32)
148 #define TCG_TARGET_HAS_div_i32          0
149 #define TCG_TARGET_HAS_rem_i32          0
150 #endif
151 #if defined(TCG_TARGET_HAS_div_i64)
152 #define TCG_TARGET_HAS_div2_i64         0
153 #elif defined(TCG_TARGET_HAS_div2_i64)
154 #define TCG_TARGET_HAS_div_i64          0
155 #define TCG_TARGET_HAS_rem_i64          0
156 #endif
157 
158 #if !defined(TCG_TARGET_HAS_v64) \
159     && !defined(TCG_TARGET_HAS_v128) \
160     && !defined(TCG_TARGET_HAS_v256)
161 #define TCG_TARGET_MAYBE_vec            0
162 #define TCG_TARGET_HAS_abs_vec          0
163 #define TCG_TARGET_HAS_neg_vec          0
164 #define TCG_TARGET_HAS_not_vec          0
165 #define TCG_TARGET_HAS_andc_vec         0
166 #define TCG_TARGET_HAS_orc_vec          0
167 #define TCG_TARGET_HAS_nand_vec         0
168 #define TCG_TARGET_HAS_nor_vec          0
169 #define TCG_TARGET_HAS_eqv_vec          0
170 #define TCG_TARGET_HAS_roti_vec         0
171 #define TCG_TARGET_HAS_rots_vec         0
172 #define TCG_TARGET_HAS_rotv_vec         0
173 #define TCG_TARGET_HAS_shi_vec          0
174 #define TCG_TARGET_HAS_shs_vec          0
175 #define TCG_TARGET_HAS_shv_vec          0
176 #define TCG_TARGET_HAS_mul_vec          0
177 #define TCG_TARGET_HAS_sat_vec          0
178 #define TCG_TARGET_HAS_minmax_vec       0
179 #define TCG_TARGET_HAS_bitsel_vec       0
180 #define TCG_TARGET_HAS_cmpsel_vec       0
181 #else
182 #define TCG_TARGET_MAYBE_vec            1
183 #endif
184 #ifndef TCG_TARGET_HAS_v64
185 #define TCG_TARGET_HAS_v64              0
186 #endif
187 #ifndef TCG_TARGET_HAS_v128
188 #define TCG_TARGET_HAS_v128             0
189 #endif
190 #ifndef TCG_TARGET_HAS_v256
191 #define TCG_TARGET_HAS_v256             0
192 #endif
193 
194 #ifndef TARGET_INSN_START_EXTRA_WORDS
195 # define TARGET_INSN_START_WORDS 1
196 #else
197 # define TARGET_INSN_START_WORDS (1 + TARGET_INSN_START_EXTRA_WORDS)
198 #endif
199 
200 typedef enum TCGOpcode {
201 #define DEF(name, oargs, iargs, cargs, flags) INDEX_op_ ## name,
202 #include "tcg/tcg-opc.h"
203 #undef DEF
204     NB_OPS,
205 } TCGOpcode;
206 
207 #define tcg_regset_set_reg(d, r)   ((d) |= (TCGRegSet)1 << (r))
208 #define tcg_regset_reset_reg(d, r) ((d) &= ~((TCGRegSet)1 << (r)))
209 #define tcg_regset_test_reg(d, r)  (((d) >> (r)) & 1)
210 
211 #ifndef TCG_TARGET_INSN_UNIT_SIZE
212 # error "Missing TCG_TARGET_INSN_UNIT_SIZE"
213 #elif TCG_TARGET_INSN_UNIT_SIZE == 1
214 typedef uint8_t tcg_insn_unit;
215 #elif TCG_TARGET_INSN_UNIT_SIZE == 2
216 typedef uint16_t tcg_insn_unit;
217 #elif TCG_TARGET_INSN_UNIT_SIZE == 4
218 typedef uint32_t tcg_insn_unit;
219 #elif TCG_TARGET_INSN_UNIT_SIZE == 8
220 typedef uint64_t tcg_insn_unit;
221 #else
222 /* The port better have done this.  */
223 #endif
224 
225 
226 #if defined CONFIG_DEBUG_TCG || defined QEMU_STATIC_ANALYSIS
227 # define tcg_debug_assert(X) do { assert(X); } while (0)
228 #else
229 # define tcg_debug_assert(X) \
230     do { if (!(X)) { __builtin_unreachable(); } } while (0)
231 #endif
232 
233 typedef struct TCGRelocation TCGRelocation;
234 struct TCGRelocation {
235     QSIMPLEQ_ENTRY(TCGRelocation) next;
236     tcg_insn_unit *ptr;
237     intptr_t addend;
238     int type;
239 };
240 
241 typedef struct TCGLabel TCGLabel;
242 struct TCGLabel {
243     unsigned present : 1;
244     unsigned has_value : 1;
245     unsigned id : 14;
246     unsigned refs : 16;
247     union {
248         uintptr_t value;
249         const tcg_insn_unit *value_ptr;
250     } u;
251     QSIMPLEQ_HEAD(, TCGRelocation) relocs;
252     QSIMPLEQ_ENTRY(TCGLabel) next;
253 };
254 
255 typedef struct TCGPool {
256     struct TCGPool *next;
257     int size;
258     uint8_t data[] __attribute__ ((aligned));
259 } TCGPool;
260 
261 #define TCG_POOL_CHUNK_SIZE 32768
262 
263 #define TCG_MAX_TEMPS 512
264 #define TCG_MAX_INSNS 512
265 
266 /* when the size of the arguments of a called function is smaller than
267    this value, they are statically allocated in the TB stack frame */
268 #define TCG_STATIC_CALL_ARGS_SIZE 128
269 
270 typedef enum TCGType {
271     TCG_TYPE_I32,
272     TCG_TYPE_I64,
273     TCG_TYPE_I128,
274 
275     TCG_TYPE_V64,
276     TCG_TYPE_V128,
277     TCG_TYPE_V256,
278 
279     /* Number of different types (integer not enum) */
280 #define TCG_TYPE_COUNT  (TCG_TYPE_V256 + 1)
281 
282     /* An alias for the size of the host register.  */
283 #if TCG_TARGET_REG_BITS == 32
284     TCG_TYPE_REG = TCG_TYPE_I32,
285 #else
286     TCG_TYPE_REG = TCG_TYPE_I64,
287 #endif
288 
289     /* An alias for the size of the native pointer.  */
290 #if UINTPTR_MAX == UINT32_MAX
291     TCG_TYPE_PTR = TCG_TYPE_I32,
292 #else
293     TCG_TYPE_PTR = TCG_TYPE_I64,
294 #endif
295 
296     /* An alias for the size of the target "long", aka register.  */
297 #if TARGET_LONG_BITS == 64
298     TCG_TYPE_TL = TCG_TYPE_I64,
299 #else
300     TCG_TYPE_TL = TCG_TYPE_I32,
301 #endif
302 } TCGType;
303 
304 /**
305  * tcg_type_size
306  * @t: type
307  *
308  * Return the size of the type in bytes.
309  */
310 static inline int tcg_type_size(TCGType t)
311 {
312     unsigned i = t;
313     if (i >= TCG_TYPE_V64) {
314         tcg_debug_assert(i < TCG_TYPE_COUNT);
315         i -= TCG_TYPE_V64 - 1;
316     }
317     return 4 << i;
318 }
319 
320 /**
321  * get_alignment_bits
322  * @memop: MemOp value
323  *
324  * Extract the alignment size from the memop.
325  */
326 static inline unsigned get_alignment_bits(MemOp memop)
327 {
328     unsigned a = memop & MO_AMASK;
329 
330     if (a == MO_UNALN) {
331         /* No alignment required.  */
332         a = 0;
333     } else if (a == MO_ALIGN) {
334         /* A natural alignment requirement.  */
335         a = memop & MO_SIZE;
336     } else {
337         /* A specific alignment requirement.  */
338         a = a >> MO_ASHIFT;
339     }
340 #if defined(CONFIG_SOFTMMU)
341     /* The requested alignment cannot overlap the TLB flags.  */
342     tcg_debug_assert((TLB_FLAGS_MASK & ((1 << a) - 1)) == 0);
343 #endif
344     return a;
345 }
346 
347 typedef tcg_target_ulong TCGArg;
348 
349 /* Define type and accessor macros for TCG variables.
350 
351    TCG variables are the inputs and outputs of TCG ops, as described
352    in tcg/README. Target CPU front-end code uses these types to deal
353    with TCG variables as it emits TCG code via the tcg_gen_* functions.
354    They come in several flavours:
355     * TCGv_i32  : 32 bit integer type
356     * TCGv_i64  : 64 bit integer type
357     * TCGv_i128 : 128 bit integer type
358     * TCGv_ptr  : a host pointer type
359     * TCGv_vec  : a host vector type; the exact size is not exposed
360                   to the CPU front-end code.
361     * TCGv      : an integer type the same size as target_ulong
362                   (an alias for either TCGv_i32 or TCGv_i64)
363    The compiler's type checking will complain if you mix them
364    up and pass the wrong sized TCGv to a function.
365 
366    Users of tcg_gen_* don't need to know about any of the internal
367    details of these, and should treat them as opaque types.
368    You won't be able to look inside them in a debugger either.
369 
370    Internal implementation details follow:
371 
372    Note that there is no definition of the structs TCGv_i32_d etc anywhere.
373    This is deliberate, because the values we store in variables of type
374    TCGv_i32 are not really pointers-to-structures. They're just small
375    integers, but keeping them in pointer types like this means that the
376    compiler will complain if you accidentally pass a TCGv_i32 to a
377    function which takes a TCGv_i64, and so on. Only the internals of
378    TCG need to care about the actual contents of the types.  */
379 
380 typedef struct TCGv_i32_d *TCGv_i32;
381 typedef struct TCGv_i64_d *TCGv_i64;
382 typedef struct TCGv_i128_d *TCGv_i128;
383 typedef struct TCGv_ptr_d *TCGv_ptr;
384 typedef struct TCGv_vec_d *TCGv_vec;
385 typedef TCGv_ptr TCGv_env;
386 #if TARGET_LONG_BITS == 32
387 #define TCGv TCGv_i32
388 #elif TARGET_LONG_BITS == 64
389 #define TCGv TCGv_i64
390 #else
391 #error Unhandled TARGET_LONG_BITS value
392 #endif
393 
394 /* call flags */
395 /* Helper does not read globals (either directly or through an exception). It
396    implies TCG_CALL_NO_WRITE_GLOBALS. */
397 #define TCG_CALL_NO_READ_GLOBALS    0x0001
398 /* Helper does not write globals */
399 #define TCG_CALL_NO_WRITE_GLOBALS   0x0002
400 /* Helper can be safely suppressed if the return value is not used. */
401 #define TCG_CALL_NO_SIDE_EFFECTS    0x0004
402 /* Helper is G_NORETURN.  */
403 #define TCG_CALL_NO_RETURN          0x0008
404 /* Helper is part of Plugins.  */
405 #define TCG_CALL_PLUGIN             0x0010
406 
407 /* convenience version of most used call flags */
408 #define TCG_CALL_NO_RWG         TCG_CALL_NO_READ_GLOBALS
409 #define TCG_CALL_NO_WG          TCG_CALL_NO_WRITE_GLOBALS
410 #define TCG_CALL_NO_SE          TCG_CALL_NO_SIDE_EFFECTS
411 #define TCG_CALL_NO_RWG_SE      (TCG_CALL_NO_RWG | TCG_CALL_NO_SE)
412 #define TCG_CALL_NO_WG_SE       (TCG_CALL_NO_WG | TCG_CALL_NO_SE)
413 
414 /*
415  * Flags for the bswap opcodes.
416  * If IZ, the input is zero-extended, otherwise unknown.
417  * If OZ or OS, the output is zero- or sign-extended respectively,
418  * otherwise the high bits are undefined.
419  */
420 enum {
421     TCG_BSWAP_IZ = 1,
422     TCG_BSWAP_OZ = 2,
423     TCG_BSWAP_OS = 4,
424 };
425 
426 typedef enum TCGTempVal {
427     TEMP_VAL_DEAD,
428     TEMP_VAL_REG,
429     TEMP_VAL_MEM,
430     TEMP_VAL_CONST,
431 } TCGTempVal;
432 
433 typedef enum TCGTempKind {
434     /* Temp is dead at the end of all basic blocks. */
435     TEMP_NORMAL,
436     /* Temp is live across conditional branch, but dead otherwise. */
437     TEMP_EBB,
438     /* Temp is saved across basic blocks but dead at the end of TBs. */
439     TEMP_LOCAL,
440     /* Temp is saved across both basic blocks and translation blocks. */
441     TEMP_GLOBAL,
442     /* Temp is in a fixed register. */
443     TEMP_FIXED,
444     /* Temp is a fixed constant. */
445     TEMP_CONST,
446 } TCGTempKind;
447 
448 typedef struct TCGTemp {
449     TCGReg reg:8;
450     TCGTempVal val_type:8;
451     TCGType base_type:8;
452     TCGType type:8;
453     TCGTempKind kind:3;
454     unsigned int indirect_reg:1;
455     unsigned int indirect_base:1;
456     unsigned int mem_coherent:1;
457     unsigned int mem_allocated:1;
458     unsigned int temp_allocated:1;
459     unsigned int temp_subindex:1;
460 
461     int64_t val;
462     struct TCGTemp *mem_base;
463     intptr_t mem_offset;
464     const char *name;
465 
466     /* Pass-specific information that can be stored for a temporary.
467        One word worth of integer data, and one pointer to data
468        allocated separately.  */
469     uintptr_t state;
470     void *state_ptr;
471 } TCGTemp;
472 
473 typedef struct TCGContext TCGContext;
474 
475 typedef struct TCGTempSet {
476     unsigned long l[BITS_TO_LONGS(TCG_MAX_TEMPS)];
477 } TCGTempSet;
478 
479 /*
480  * With 1 128-bit output, a 32-bit host requires 4 output parameters,
481  * which leaves a maximum of 28 other slots.  Which is enough for 7
482  * 128-bit operands.
483  */
484 #define DEAD_ARG  (1 << 4)
485 #define SYNC_ARG  (1 << 0)
486 typedef uint32_t TCGLifeData;
487 
488 typedef struct TCGOp {
489     TCGOpcode opc   : 8;
490     unsigned nargs  : 8;
491 
492     /* Parameters for this opcode.  See below.  */
493     unsigned param1 : 8;
494     unsigned param2 : 8;
495 
496     /* Lifetime data of the operands.  */
497     TCGLifeData life;
498 
499     /* Next and previous opcodes.  */
500     QTAILQ_ENTRY(TCGOp) link;
501 
502     /* Register preferences for the output(s).  */
503     TCGRegSet output_pref[2];
504 
505     /* Arguments for the opcode.  */
506     TCGArg args[];
507 } TCGOp;
508 
509 #define TCGOP_CALLI(X)    (X)->param1
510 #define TCGOP_CALLO(X)    (X)->param2
511 
512 #define TCGOP_VECL(X)     (X)->param1
513 #define TCGOP_VECE(X)     (X)->param2
514 
515 /* Make sure operands fit in the bitfields above.  */
516 QEMU_BUILD_BUG_ON(NB_OPS > (1 << 8));
517 
518 static inline TCGRegSet output_pref(const TCGOp *op, unsigned i)
519 {
520     return i < ARRAY_SIZE(op->output_pref) ? op->output_pref[i] : 0;
521 }
522 
523 typedef struct TCGProfile {
524     int64_t cpu_exec_time;
525     int64_t tb_count1;
526     int64_t tb_count;
527     int64_t op_count; /* total insn count */
528     int op_count_max; /* max insn per TB */
529     int temp_count_max;
530     int64_t temp_count;
531     int64_t del_op_count;
532     int64_t code_in_len;
533     int64_t code_out_len;
534     int64_t search_out_len;
535     int64_t interm_time;
536     int64_t code_time;
537     int64_t la_time;
538     int64_t opt_time;
539     int64_t restore_count;
540     int64_t restore_time;
541     int64_t table_op_count[NB_OPS];
542 } TCGProfile;
543 
544 struct TCGContext {
545     uint8_t *pool_cur, *pool_end;
546     TCGPool *pool_first, *pool_current, *pool_first_large;
547     int nb_labels;
548     int nb_globals;
549     int nb_temps;
550     int nb_indirects;
551     int nb_ops;
552 
553     TCGRegSet reserved_regs;
554     intptr_t current_frame_offset;
555     intptr_t frame_start;
556     intptr_t frame_end;
557     TCGTemp *frame_temp;
558 
559     TranslationBlock *gen_tb;     /* tb for which code is being generated */
560     tcg_insn_unit *code_buf;      /* pointer for start of tb */
561     tcg_insn_unit *code_ptr;      /* pointer for running end of tb */
562 
563 #ifdef CONFIG_PROFILER
564     TCGProfile prof;
565 #endif
566 
567 #ifdef CONFIG_DEBUG_TCG
568     int temps_in_use;
569     int goto_tb_issue_mask;
570     const TCGOpcode *vecop_list;
571 #endif
572 
573     /* Code generation.  Note that we specifically do not use tcg_insn_unit
574        here, because there's too much arithmetic throughout that relies
575        on addition and subtraction working on bytes.  Rely on the GCC
576        extension that allows arithmetic on void*.  */
577     void *code_gen_buffer;
578     size_t code_gen_buffer_size;
579     void *code_gen_ptr;
580     void *data_gen_ptr;
581 
582     /* Threshold to flush the translated code buffer.  */
583     void *code_gen_highwater;
584 
585     /* Track which vCPU triggers events */
586     CPUState *cpu;                      /* *_trans */
587 
588     /* These structures are private to tcg-target.c.inc.  */
589 #ifdef TCG_TARGET_NEED_LDST_LABELS
590     QSIMPLEQ_HEAD(, TCGLabelQemuLdst) ldst_labels;
591 #endif
592 #ifdef TCG_TARGET_NEED_POOL_LABELS
593     struct TCGLabelPoolData *pool_labels;
594 #endif
595 
596     TCGLabel *exitreq_label;
597 
598 #ifdef CONFIG_PLUGIN
599     /*
600      * We keep one plugin_tb struct per TCGContext. Note that on every TB
601      * translation we clear but do not free its contents; this way we
602      * avoid a lot of malloc/free churn, since after a few TB's it's
603      * unlikely that we'll need to allocate either more instructions or more
604      * space for instructions (for variable-instruction-length ISAs).
605      */
606     struct qemu_plugin_tb *plugin_tb;
607 
608     /* descriptor of the instruction being translated */
609     struct qemu_plugin_insn *plugin_insn;
610 #endif
611 
612     GHashTable *const_table[TCG_TYPE_COUNT];
613     TCGTempSet free_temps[TCG_TYPE_COUNT * 2];
614     TCGTemp temps[TCG_MAX_TEMPS]; /* globals first, temps after */
615 
616     QTAILQ_HEAD(, TCGOp) ops, free_ops;
617     QSIMPLEQ_HEAD(, TCGLabel) labels;
618 
619     /* Tells which temporary holds a given register.
620        It does not take into account fixed registers */
621     TCGTemp *reg_to_temp[TCG_TARGET_NB_REGS];
622 
623     uint16_t gen_insn_end_off[TCG_MAX_INSNS];
624     target_ulong gen_insn_data[TCG_MAX_INSNS][TARGET_INSN_START_WORDS];
625 
626     /* Exit to translator on overflow. */
627     sigjmp_buf jmp_trans;
628 };
629 
630 static inline bool temp_readonly(TCGTemp *ts)
631 {
632     return ts->kind >= TEMP_FIXED;
633 }
634 
635 extern __thread TCGContext *tcg_ctx;
636 extern const void *tcg_code_gen_epilogue;
637 extern uintptr_t tcg_splitwx_diff;
638 extern TCGv_env cpu_env;
639 
640 bool in_code_gen_buffer(const void *p);
641 
642 #ifdef CONFIG_DEBUG_TCG
643 const void *tcg_splitwx_to_rx(void *rw);
644 void *tcg_splitwx_to_rw(const void *rx);
645 #else
646 static inline const void *tcg_splitwx_to_rx(void *rw)
647 {
648     return rw ? rw + tcg_splitwx_diff : NULL;
649 }
650 
651 static inline void *tcg_splitwx_to_rw(const void *rx)
652 {
653     return rx ? (void *)rx - tcg_splitwx_diff : NULL;
654 }
655 #endif
656 
657 static inline size_t temp_idx(TCGTemp *ts)
658 {
659     ptrdiff_t n = ts - tcg_ctx->temps;
660     tcg_debug_assert(n >= 0 && n < tcg_ctx->nb_temps);
661     return n;
662 }
663 
664 static inline TCGArg temp_arg(TCGTemp *ts)
665 {
666     return (uintptr_t)ts;
667 }
668 
669 static inline TCGTemp *arg_temp(TCGArg a)
670 {
671     return (TCGTemp *)(uintptr_t)a;
672 }
673 
674 /* Using the offset of a temporary, relative to TCGContext, rather than
675    its index means that we don't use 0.  That leaves offset 0 free for
676    a NULL representation without having to leave index 0 unused.  */
677 static inline TCGTemp *tcgv_i32_temp(TCGv_i32 v)
678 {
679     uintptr_t o = (uintptr_t)v;
680     TCGTemp *t = (void *)tcg_ctx + o;
681     tcg_debug_assert(offsetof(TCGContext, temps[temp_idx(t)]) == o);
682     return t;
683 }
684 
685 static inline TCGTemp *tcgv_i64_temp(TCGv_i64 v)
686 {
687     return tcgv_i32_temp((TCGv_i32)v);
688 }
689 
690 static inline TCGTemp *tcgv_i128_temp(TCGv_i128 v)
691 {
692     return tcgv_i32_temp((TCGv_i32)v);
693 }
694 
695 static inline TCGTemp *tcgv_ptr_temp(TCGv_ptr v)
696 {
697     return tcgv_i32_temp((TCGv_i32)v);
698 }
699 
700 static inline TCGTemp *tcgv_vec_temp(TCGv_vec v)
701 {
702     return tcgv_i32_temp((TCGv_i32)v);
703 }
704 
705 static inline TCGArg tcgv_i32_arg(TCGv_i32 v)
706 {
707     return temp_arg(tcgv_i32_temp(v));
708 }
709 
710 static inline TCGArg tcgv_i64_arg(TCGv_i64 v)
711 {
712     return temp_arg(tcgv_i64_temp(v));
713 }
714 
715 static inline TCGArg tcgv_i128_arg(TCGv_i128 v)
716 {
717     return temp_arg(tcgv_i128_temp(v));
718 }
719 
720 static inline TCGArg tcgv_ptr_arg(TCGv_ptr v)
721 {
722     return temp_arg(tcgv_ptr_temp(v));
723 }
724 
725 static inline TCGArg tcgv_vec_arg(TCGv_vec v)
726 {
727     return temp_arg(tcgv_vec_temp(v));
728 }
729 
730 static inline TCGv_i32 temp_tcgv_i32(TCGTemp *t)
731 {
732     (void)temp_idx(t); /* trigger embedded assert */
733     return (TCGv_i32)((void *)t - (void *)tcg_ctx);
734 }
735 
736 static inline TCGv_i64 temp_tcgv_i64(TCGTemp *t)
737 {
738     return (TCGv_i64)temp_tcgv_i32(t);
739 }
740 
741 static inline TCGv_i128 temp_tcgv_i128(TCGTemp *t)
742 {
743     return (TCGv_i128)temp_tcgv_i32(t);
744 }
745 
746 static inline TCGv_ptr temp_tcgv_ptr(TCGTemp *t)
747 {
748     return (TCGv_ptr)temp_tcgv_i32(t);
749 }
750 
751 static inline TCGv_vec temp_tcgv_vec(TCGTemp *t)
752 {
753     return (TCGv_vec)temp_tcgv_i32(t);
754 }
755 
756 static inline TCGArg tcg_get_insn_param(TCGOp *op, int arg)
757 {
758     return op->args[arg];
759 }
760 
761 static inline void tcg_set_insn_param(TCGOp *op, int arg, TCGArg v)
762 {
763     op->args[arg] = v;
764 }
765 
766 static inline target_ulong tcg_get_insn_start_param(TCGOp *op, int arg)
767 {
768 #if TARGET_LONG_BITS <= TCG_TARGET_REG_BITS
769     return tcg_get_insn_param(op, arg);
770 #else
771     return tcg_get_insn_param(op, arg * 2) |
772            ((uint64_t)tcg_get_insn_param(op, arg * 2 + 1) << 32);
773 #endif
774 }
775 
776 static inline void tcg_set_insn_start_param(TCGOp *op, int arg, target_ulong v)
777 {
778 #if TARGET_LONG_BITS <= TCG_TARGET_REG_BITS
779     tcg_set_insn_param(op, arg, v);
780 #else
781     tcg_set_insn_param(op, arg * 2, v);
782     tcg_set_insn_param(op, arg * 2 + 1, v >> 32);
783 #endif
784 }
785 
786 /* The last op that was emitted.  */
787 static inline TCGOp *tcg_last_op(void)
788 {
789     return QTAILQ_LAST(&tcg_ctx->ops);
790 }
791 
792 /* Test for whether to terminate the TB for using too many opcodes.  */
793 static inline bool tcg_op_buf_full(void)
794 {
795     /* This is not a hard limit, it merely stops translation when
796      * we have produced "enough" opcodes.  We want to limit TB size
797      * such that a RISC host can reasonably use a 16-bit signed
798      * branch within the TB.  We also need to be mindful of the
799      * 16-bit unsigned offsets, TranslationBlock.jmp_reset_offset[]
800      * and TCGContext.gen_insn_end_off[].
801      */
802     return tcg_ctx->nb_ops >= 4000;
803 }
804 
805 /* pool based memory allocation */
806 
807 /* user-mode: mmap_lock must be held for tcg_malloc_internal. */
808 void *tcg_malloc_internal(TCGContext *s, int size);
809 void tcg_pool_reset(TCGContext *s);
810 TranslationBlock *tcg_tb_alloc(TCGContext *s);
811 
812 void tcg_region_reset_all(void);
813 
814 size_t tcg_code_size(void);
815 size_t tcg_code_capacity(void);
816 
817 void tcg_tb_insert(TranslationBlock *tb);
818 void tcg_tb_remove(TranslationBlock *tb);
819 TranslationBlock *tcg_tb_lookup(uintptr_t tc_ptr);
820 void tcg_tb_foreach(GTraverseFunc func, gpointer user_data);
821 size_t tcg_nb_tbs(void);
822 
823 /* user-mode: Called with mmap_lock held.  */
824 static inline void *tcg_malloc(int size)
825 {
826     TCGContext *s = tcg_ctx;
827     uint8_t *ptr, *ptr_end;
828 
829     /* ??? This is a weak placeholder for minimum malloc alignment.  */
830     size = QEMU_ALIGN_UP(size, 8);
831 
832     ptr = s->pool_cur;
833     ptr_end = ptr + size;
834     if (unlikely(ptr_end > s->pool_end)) {
835         return tcg_malloc_internal(tcg_ctx, size);
836     } else {
837         s->pool_cur = ptr_end;
838         return ptr;
839     }
840 }
841 
842 void tcg_init(size_t tb_size, int splitwx, unsigned max_cpus);
843 void tcg_register_thread(void);
844 void tcg_prologue_init(TCGContext *s);
845 void tcg_func_start(TCGContext *s);
846 
847 int tcg_gen_code(TCGContext *s, TranslationBlock *tb, target_ulong pc_start);
848 
849 void tb_target_set_jmp_target(const TranslationBlock *, int,
850                               uintptr_t, uintptr_t);
851 
852 void tcg_set_frame(TCGContext *s, TCGReg reg, intptr_t start, intptr_t size);
853 
854 TCGTemp *tcg_global_mem_new_internal(TCGType, TCGv_ptr,
855                                      intptr_t, const char *);
856 TCGTemp *tcg_temp_new_internal(TCGType, bool);
857 void tcg_temp_free_internal(TCGTemp *);
858 TCGv_vec tcg_temp_new_vec(TCGType type);
859 TCGv_vec tcg_temp_new_vec_matching(TCGv_vec match);
860 
861 static inline void tcg_temp_free_i32(TCGv_i32 arg)
862 {
863     tcg_temp_free_internal(tcgv_i32_temp(arg));
864 }
865 
866 static inline void tcg_temp_free_i64(TCGv_i64 arg)
867 {
868     tcg_temp_free_internal(tcgv_i64_temp(arg));
869 }
870 
871 static inline void tcg_temp_free_i128(TCGv_i128 arg)
872 {
873     tcg_temp_free_internal(tcgv_i128_temp(arg));
874 }
875 
876 static inline void tcg_temp_free_ptr(TCGv_ptr arg)
877 {
878     tcg_temp_free_internal(tcgv_ptr_temp(arg));
879 }
880 
881 static inline void tcg_temp_free_vec(TCGv_vec arg)
882 {
883     tcg_temp_free_internal(tcgv_vec_temp(arg));
884 }
885 
886 static inline TCGv_i32 tcg_global_mem_new_i32(TCGv_ptr reg, intptr_t offset,
887                                               const char *name)
888 {
889     TCGTemp *t = tcg_global_mem_new_internal(TCG_TYPE_I32, reg, offset, name);
890     return temp_tcgv_i32(t);
891 }
892 
893 static inline TCGv_i32 tcg_temp_new_i32(void)
894 {
895     TCGTemp *t = tcg_temp_new_internal(TCG_TYPE_I32, false);
896     return temp_tcgv_i32(t);
897 }
898 
899 static inline TCGv_i32 tcg_temp_local_new_i32(void)
900 {
901     TCGTemp *t = tcg_temp_new_internal(TCG_TYPE_I32, true);
902     return temp_tcgv_i32(t);
903 }
904 
905 static inline TCGv_i64 tcg_global_mem_new_i64(TCGv_ptr reg, intptr_t offset,
906                                               const char *name)
907 {
908     TCGTemp *t = tcg_global_mem_new_internal(TCG_TYPE_I64, reg, offset, name);
909     return temp_tcgv_i64(t);
910 }
911 
912 static inline TCGv_i64 tcg_temp_new_i64(void)
913 {
914     TCGTemp *t = tcg_temp_new_internal(TCG_TYPE_I64, false);
915     return temp_tcgv_i64(t);
916 }
917 
918 static inline TCGv_i64 tcg_temp_local_new_i64(void)
919 {
920     TCGTemp *t = tcg_temp_new_internal(TCG_TYPE_I64, true);
921     return temp_tcgv_i64(t);
922 }
923 
924 static inline TCGv_i128 tcg_temp_new_i128(void)
925 {
926     TCGTemp *t = tcg_temp_new_internal(TCG_TYPE_I128, false);
927     return temp_tcgv_i128(t);
928 }
929 
930 static inline TCGv_i128 tcg_temp_local_new_i128(void)
931 {
932     TCGTemp *t = tcg_temp_new_internal(TCG_TYPE_I128, true);
933     return temp_tcgv_i128(t);
934 }
935 
936 static inline TCGv_ptr tcg_global_mem_new_ptr(TCGv_ptr reg, intptr_t offset,
937                                               const char *name)
938 {
939     TCGTemp *t = tcg_global_mem_new_internal(TCG_TYPE_PTR, reg, offset, name);
940     return temp_tcgv_ptr(t);
941 }
942 
943 static inline TCGv_ptr tcg_temp_new_ptr(void)
944 {
945     TCGTemp *t = tcg_temp_new_internal(TCG_TYPE_PTR, false);
946     return temp_tcgv_ptr(t);
947 }
948 
949 static inline TCGv_ptr tcg_temp_local_new_ptr(void)
950 {
951     TCGTemp *t = tcg_temp_new_internal(TCG_TYPE_PTR, true);
952     return temp_tcgv_ptr(t);
953 }
954 
955 #if defined(CONFIG_DEBUG_TCG)
956 /* If you call tcg_clear_temp_count() at the start of a section of
957  * code which is not supposed to leak any TCG temporaries, then
958  * calling tcg_check_temp_count() at the end of the section will
959  * return 1 if the section did in fact leak a temporary.
960  */
961 void tcg_clear_temp_count(void);
962 int tcg_check_temp_count(void);
963 #else
964 #define tcg_clear_temp_count() do { } while (0)
965 #define tcg_check_temp_count() 0
966 #endif
967 
968 int64_t tcg_cpu_exec_time(void);
969 void tcg_dump_info(GString *buf);
970 void tcg_dump_op_count(GString *buf);
971 
972 #define TCG_CT_CONST  1 /* any constant of register size */
973 
974 typedef struct TCGArgConstraint {
975     unsigned ct : 16;
976     unsigned alias_index : 4;
977     unsigned sort_index : 4;
978     unsigned pair_index : 4;
979     unsigned pair : 2;  /* 0: none, 1: first, 2: second, 3: second alias */
980     bool oalias : 1;
981     bool ialias : 1;
982     bool newreg : 1;
983     TCGRegSet regs;
984 } TCGArgConstraint;
985 
986 #define TCG_MAX_OP_ARGS 16
987 
988 /* Bits for TCGOpDef->flags, 8 bits available, all used.  */
989 enum {
990     /* Instruction exits the translation block.  */
991     TCG_OPF_BB_EXIT      = 0x01,
992     /* Instruction defines the end of a basic block.  */
993     TCG_OPF_BB_END       = 0x02,
994     /* Instruction clobbers call registers and potentially update globals.  */
995     TCG_OPF_CALL_CLOBBER = 0x04,
996     /* Instruction has side effects: it cannot be removed if its outputs
997        are not used, and might trigger exceptions.  */
998     TCG_OPF_SIDE_EFFECTS = 0x08,
999     /* Instruction operands are 64-bits (otherwise 32-bits).  */
1000     TCG_OPF_64BIT        = 0x10,
1001     /* Instruction is optional and not implemented by the host, or insn
1002        is generic and should not be implemened by the host.  */
1003     TCG_OPF_NOT_PRESENT  = 0x20,
1004     /* Instruction operands are vectors.  */
1005     TCG_OPF_VECTOR       = 0x40,
1006     /* Instruction is a conditional branch. */
1007     TCG_OPF_COND_BRANCH  = 0x80
1008 };
1009 
1010 typedef struct TCGOpDef {
1011     const char *name;
1012     uint8_t nb_oargs, nb_iargs, nb_cargs, nb_args;
1013     uint8_t flags;
1014     TCGArgConstraint *args_ct;
1015 } TCGOpDef;
1016 
1017 extern TCGOpDef tcg_op_defs[];
1018 extern const size_t tcg_op_defs_max;
1019 
1020 typedef struct TCGTargetOpDef {
1021     TCGOpcode op;
1022     const char *args_ct_str[TCG_MAX_OP_ARGS];
1023 } TCGTargetOpDef;
1024 
1025 #define tcg_abort() \
1026 do {\
1027     fprintf(stderr, "%s:%d: tcg fatal error\n", __FILE__, __LINE__);\
1028     abort();\
1029 } while (0)
1030 
1031 bool tcg_op_supported(TCGOpcode op);
1032 
1033 void tcg_gen_callN(void *func, TCGTemp *ret, int nargs, TCGTemp **args);
1034 
1035 TCGOp *tcg_emit_op(TCGOpcode opc, unsigned nargs);
1036 void tcg_op_remove(TCGContext *s, TCGOp *op);
1037 TCGOp *tcg_op_insert_before(TCGContext *s, TCGOp *op,
1038                             TCGOpcode opc, unsigned nargs);
1039 TCGOp *tcg_op_insert_after(TCGContext *s, TCGOp *op,
1040                            TCGOpcode opc, unsigned nargs);
1041 
1042 /**
1043  * tcg_remove_ops_after:
1044  * @op: target operation
1045  *
1046  * Discard any opcodes emitted since @op.  Expected usage is to save
1047  * a starting point with tcg_last_op(), speculatively emit opcodes,
1048  * then decide whether or not to keep those opcodes after the fact.
1049  */
1050 void tcg_remove_ops_after(TCGOp *op);
1051 
1052 void tcg_optimize(TCGContext *s);
1053 
1054 /* Allocate a new temporary and initialize it with a constant. */
1055 TCGv_i32 tcg_const_i32(int32_t val);
1056 TCGv_i64 tcg_const_i64(int64_t val);
1057 TCGv_i32 tcg_const_local_i32(int32_t val);
1058 TCGv_i64 tcg_const_local_i64(int64_t val);
1059 TCGv_vec tcg_const_zeros_vec(TCGType);
1060 TCGv_vec tcg_const_ones_vec(TCGType);
1061 TCGv_vec tcg_const_zeros_vec_matching(TCGv_vec);
1062 TCGv_vec tcg_const_ones_vec_matching(TCGv_vec);
1063 
1064 /*
1065  * Locate or create a read-only temporary that is a constant.
1066  * This kind of temporary need not be freed, but for convenience
1067  * will be silently ignored by tcg_temp_free_*.
1068  */
1069 TCGTemp *tcg_constant_internal(TCGType type, int64_t val);
1070 
1071 static inline TCGv_i32 tcg_constant_i32(int32_t val)
1072 {
1073     return temp_tcgv_i32(tcg_constant_internal(TCG_TYPE_I32, val));
1074 }
1075 
1076 static inline TCGv_i64 tcg_constant_i64(int64_t val)
1077 {
1078     return temp_tcgv_i64(tcg_constant_internal(TCG_TYPE_I64, val));
1079 }
1080 
1081 TCGv_vec tcg_constant_vec(TCGType type, unsigned vece, int64_t val);
1082 TCGv_vec tcg_constant_vec_matching(TCGv_vec match, unsigned vece, int64_t val);
1083 
1084 #if UINTPTR_MAX == UINT32_MAX
1085 # define tcg_const_ptr(x)        ((TCGv_ptr)tcg_const_i32((intptr_t)(x)))
1086 # define tcg_const_local_ptr(x)  ((TCGv_ptr)tcg_const_local_i32((intptr_t)(x)))
1087 # define tcg_constant_ptr(x)     ((TCGv_ptr)tcg_constant_i32((intptr_t)(x)))
1088 #else
1089 # define tcg_const_ptr(x)        ((TCGv_ptr)tcg_const_i64((intptr_t)(x)))
1090 # define tcg_const_local_ptr(x)  ((TCGv_ptr)tcg_const_local_i64((intptr_t)(x)))
1091 # define tcg_constant_ptr(x)     ((TCGv_ptr)tcg_constant_i64((intptr_t)(x)))
1092 #endif
1093 
1094 TCGLabel *gen_new_label(void);
1095 
1096 /**
1097  * label_arg
1098  * @l: label
1099  *
1100  * Encode a label for storage in the TCG opcode stream.
1101  */
1102 
1103 static inline TCGArg label_arg(TCGLabel *l)
1104 {
1105     return (uintptr_t)l;
1106 }
1107 
1108 /**
1109  * arg_label
1110  * @i: value
1111  *
1112  * The opposite of label_arg.  Retrieve a label from the
1113  * encoding of the TCG opcode stream.
1114  */
1115 
1116 static inline TCGLabel *arg_label(TCGArg i)
1117 {
1118     return (TCGLabel *)(uintptr_t)i;
1119 }
1120 
1121 /**
1122  * tcg_ptr_byte_diff
1123  * @a, @b: addresses to be differenced
1124  *
1125  * There are many places within the TCG backends where we need a byte
1126  * difference between two pointers.  While this can be accomplished
1127  * with local casting, it's easy to get wrong -- especially if one is
1128  * concerned with the signedness of the result.
1129  *
1130  * This version relies on GCC's void pointer arithmetic to get the
1131  * correct result.
1132  */
1133 
1134 static inline ptrdiff_t tcg_ptr_byte_diff(const void *a, const void *b)
1135 {
1136     return a - b;
1137 }
1138 
1139 /**
1140  * tcg_pcrel_diff
1141  * @s: the tcg context
1142  * @target: address of the target
1143  *
1144  * Produce a pc-relative difference, from the current code_ptr
1145  * to the destination address.
1146  */
1147 
1148 static inline ptrdiff_t tcg_pcrel_diff(TCGContext *s, const void *target)
1149 {
1150     return tcg_ptr_byte_diff(target, tcg_splitwx_to_rx(s->code_ptr));
1151 }
1152 
1153 /**
1154  * tcg_tbrel_diff
1155  * @s: the tcg context
1156  * @target: address of the target
1157  *
1158  * Produce a difference, from the beginning of the current TB code
1159  * to the destination address.
1160  */
1161 static inline ptrdiff_t tcg_tbrel_diff(TCGContext *s, const void *target)
1162 {
1163     return tcg_ptr_byte_diff(target, tcg_splitwx_to_rx(s->code_buf));
1164 }
1165 
1166 /**
1167  * tcg_current_code_size
1168  * @s: the tcg context
1169  *
1170  * Compute the current code size within the translation block.
1171  * This is used to fill in qemu's data structures for goto_tb.
1172  */
1173 
1174 static inline size_t tcg_current_code_size(TCGContext *s)
1175 {
1176     return tcg_ptr_byte_diff(s->code_ptr, s->code_buf);
1177 }
1178 
1179 /**
1180  * tcg_qemu_tb_exec:
1181  * @env: pointer to CPUArchState for the CPU
1182  * @tb_ptr: address of generated code for the TB to execute
1183  *
1184  * Start executing code from a given translation block.
1185  * Where translation blocks have been linked, execution
1186  * may proceed from the given TB into successive ones.
1187  * Control eventually returns only when some action is needed
1188  * from the top-level loop: either control must pass to a TB
1189  * which has not yet been directly linked, or an asynchronous
1190  * event such as an interrupt needs handling.
1191  *
1192  * Return: The return value is the value passed to the corresponding
1193  * tcg_gen_exit_tb() at translation time of the last TB attempted to execute.
1194  * The value is either zero or a 4-byte aligned pointer to that TB combined
1195  * with additional information in its two least significant bits. The
1196  * additional information is encoded as follows:
1197  *  0, 1: the link between this TB and the next is via the specified
1198  *        TB index (0 or 1). That is, we left the TB via (the equivalent
1199  *        of) "goto_tb <index>". The main loop uses this to determine
1200  *        how to link the TB just executed to the next.
1201  *  2:    we are using instruction counting code generation, and we
1202  *        did not start executing this TB because the instruction counter
1203  *        would hit zero midway through it. In this case the pointer
1204  *        returned is the TB we were about to execute, and the caller must
1205  *        arrange to execute the remaining count of instructions.
1206  *  3:    we stopped because the CPU's exit_request flag was set
1207  *        (usually meaning that there is an interrupt that needs to be
1208  *        handled). The pointer returned is the TB we were about to execute
1209  *        when we noticed the pending exit request.
1210  *
1211  * If the bottom two bits indicate an exit-via-index then the CPU
1212  * state is correctly synchronised and ready for execution of the next
1213  * TB (and in particular the guest PC is the address to execute next).
1214  * Otherwise, we gave up on execution of this TB before it started, and
1215  * the caller must fix up the CPU state by calling the CPU's
1216  * synchronize_from_tb() method with the TB pointer we return (falling
1217  * back to calling the CPU's set_pc method with tb->pb if no
1218  * synchronize_from_tb() method exists).
1219  *
1220  * Note that TCG targets may use a different definition of tcg_qemu_tb_exec
1221  * to this default (which just calls the prologue.code emitted by
1222  * tcg_target_qemu_prologue()).
1223  */
1224 #define TB_EXIT_MASK      3
1225 #define TB_EXIT_IDX0      0
1226 #define TB_EXIT_IDX1      1
1227 #define TB_EXIT_IDXMAX    1
1228 #define TB_EXIT_REQUESTED 3
1229 
1230 #ifdef CONFIG_TCG_INTERPRETER
1231 uintptr_t tcg_qemu_tb_exec(CPUArchState *env, const void *tb_ptr);
1232 #else
1233 typedef uintptr_t tcg_prologue_fn(CPUArchState *env, const void *tb_ptr);
1234 extern tcg_prologue_fn *tcg_qemu_tb_exec;
1235 #endif
1236 
1237 void tcg_register_jit(const void *buf, size_t buf_size);
1238 
1239 #if TCG_TARGET_MAYBE_vec
1240 /* Return zero if the tuple (opc, type, vece) is unsupportable;
1241    return > 0 if it is directly supportable;
1242    return < 0 if we must call tcg_expand_vec_op.  */
1243 int tcg_can_emit_vec_op(TCGOpcode, TCGType, unsigned);
1244 #else
1245 static inline int tcg_can_emit_vec_op(TCGOpcode o, TCGType t, unsigned ve)
1246 {
1247     return 0;
1248 }
1249 #endif
1250 
1251 /* Expand the tuple (opc, type, vece) on the given arguments.  */
1252 void tcg_expand_vec_op(TCGOpcode, TCGType, unsigned, TCGArg, ...);
1253 
1254 /* Replicate a constant C accoring to the log2 of the element size.  */
1255 uint64_t dup_const(unsigned vece, uint64_t c);
1256 
1257 #define dup_const(VECE, C)                                         \
1258     (__builtin_constant_p(VECE)                                    \
1259      ? (  (VECE) == MO_8  ? 0x0101010101010101ull * (uint8_t)(C)   \
1260         : (VECE) == MO_16 ? 0x0001000100010001ull * (uint16_t)(C)  \
1261         : (VECE) == MO_32 ? 0x0000000100000001ull * (uint32_t)(C)  \
1262         : (VECE) == MO_64 ? (uint64_t)(C)                          \
1263         : (qemu_build_not_reached_always(), 0))                    \
1264      : dup_const(VECE, C))
1265 
1266 #if TARGET_LONG_BITS == 64
1267 # define dup_const_tl  dup_const
1268 #else
1269 # define dup_const_tl(VECE, C)                                     \
1270     (__builtin_constant_p(VECE)                                    \
1271      ? (  (VECE) == MO_8  ? 0x01010101ul * (uint8_t)(C)            \
1272         : (VECE) == MO_16 ? 0x00010001ul * (uint16_t)(C)           \
1273         : (VECE) == MO_32 ? 0x00000001ul * (uint32_t)(C)           \
1274         : (qemu_build_not_reached_always(), 0))                    \
1275      :  (target_long)dup_const(VECE, C))
1276 #endif
1277 
1278 #ifdef CONFIG_DEBUG_TCG
1279 void tcg_assert_listed_vecop(TCGOpcode);
1280 #else
1281 static inline void tcg_assert_listed_vecop(TCGOpcode op) { }
1282 #endif
1283 
1284 static inline const TCGOpcode *tcg_swap_vecop_list(const TCGOpcode *n)
1285 {
1286 #ifdef CONFIG_DEBUG_TCG
1287     const TCGOpcode *o = tcg_ctx->vecop_list;
1288     tcg_ctx->vecop_list = n;
1289     return o;
1290 #else
1291     return NULL;
1292 #endif
1293 }
1294 
1295 bool tcg_can_emit_vecop_list(const TCGOpcode *, TCGType, unsigned);
1296 
1297 #endif /* TCG_H */
1298