xref: /openbmc/qemu/tcg/tcg.c (revision f51074cd)
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 /* define it to use liveness analysis (better code) */
26 #define USE_LIVENESS_ANALYSIS
27 #define USE_TCG_OPTIMIZATIONS
28 
29 #include "config.h"
30 
31 /* Define to jump the ELF file used to communicate with GDB.  */
32 #undef DEBUG_JIT
33 
34 #if !defined(CONFIG_DEBUG_TCG) && !defined(NDEBUG)
35 /* define it to suppress various consistency checks (faster) */
36 #define NDEBUG
37 #endif
38 
39 #include "qemu-common.h"
40 #include "qemu/host-utils.h"
41 #include "qemu/timer.h"
42 
43 /* Note: the long term plan is to reduce the dependencies on the QEMU
44    CPU definitions. Currently they are used for qemu_ld/st
45    instructions */
46 #define NO_CPU_IO_DEFS
47 #include "cpu.h"
48 
49 #include "tcg-op.h"
50 
51 #if UINTPTR_MAX == UINT32_MAX
52 # define ELF_CLASS  ELFCLASS32
53 #else
54 # define ELF_CLASS  ELFCLASS64
55 #endif
56 #ifdef HOST_WORDS_BIGENDIAN
57 # define ELF_DATA   ELFDATA2MSB
58 #else
59 # define ELF_DATA   ELFDATA2LSB
60 #endif
61 
62 #include "elf.h"
63 
64 /* Forward declarations for functions declared in tcg-target.c and used here. */
65 static void tcg_target_init(TCGContext *s);
66 static void tcg_target_qemu_prologue(TCGContext *s);
67 static void patch_reloc(tcg_insn_unit *code_ptr, int type,
68                         intptr_t value, intptr_t addend);
69 
70 /* The CIE and FDE header definitions will be common to all hosts.  */
71 typedef struct {
72     uint32_t len __attribute__((aligned((sizeof(void *)))));
73     uint32_t id;
74     uint8_t version;
75     char augmentation[1];
76     uint8_t code_align;
77     uint8_t data_align;
78     uint8_t return_column;
79 } DebugFrameCIE;
80 
81 typedef struct QEMU_PACKED {
82     uint32_t len __attribute__((aligned((sizeof(void *)))));
83     uint32_t cie_offset;
84     uintptr_t func_start;
85     uintptr_t func_len;
86 } DebugFrameFDEHeader;
87 
88 typedef struct QEMU_PACKED {
89     DebugFrameCIE cie;
90     DebugFrameFDEHeader fde;
91 } DebugFrameHeader;
92 
93 static void tcg_register_jit_int(void *buf, size_t size,
94                                  const void *debug_frame,
95                                  size_t debug_frame_size)
96     __attribute__((unused));
97 
98 /* Forward declarations for functions declared and used in tcg-target.c. */
99 static int target_parse_constraint(TCGArgConstraint *ct, const char **pct_str);
100 static void tcg_out_ld(TCGContext *s, TCGType type, TCGReg ret, TCGReg arg1,
101                        intptr_t arg2);
102 static void tcg_out_mov(TCGContext *s, TCGType type, TCGReg ret, TCGReg arg);
103 static void tcg_out_movi(TCGContext *s, TCGType type,
104                          TCGReg ret, tcg_target_long arg);
105 static void tcg_out_op(TCGContext *s, TCGOpcode opc, const TCGArg *args,
106                        const int *const_args);
107 static void tcg_out_st(TCGContext *s, TCGType type, TCGReg arg, TCGReg arg1,
108                        intptr_t arg2);
109 static void tcg_out_call(TCGContext *s, tcg_insn_unit *target);
110 static int tcg_target_const_match(tcg_target_long val, TCGType type,
111                                   const TCGArgConstraint *arg_ct);
112 static void tcg_out_tb_init(TCGContext *s);
113 static void tcg_out_tb_finalize(TCGContext *s);
114 
115 
116 TCGOpDef tcg_op_defs[] = {
117 #define DEF(s, oargs, iargs, cargs, flags) { #s, oargs, iargs, cargs, iargs + oargs + cargs, flags },
118 #include "tcg-opc.h"
119 #undef DEF
120 };
121 const size_t tcg_op_defs_max = ARRAY_SIZE(tcg_op_defs);
122 
123 static TCGRegSet tcg_target_available_regs[2];
124 static TCGRegSet tcg_target_call_clobber_regs;
125 
126 #if TCG_TARGET_INSN_UNIT_SIZE == 1
127 static __attribute__((unused)) inline void tcg_out8(TCGContext *s, uint8_t v)
128 {
129     *s->code_ptr++ = v;
130 }
131 
132 static __attribute__((unused)) inline void tcg_patch8(tcg_insn_unit *p,
133                                                       uint8_t v)
134 {
135     *p = v;
136 }
137 #endif
138 
139 #if TCG_TARGET_INSN_UNIT_SIZE <= 2
140 static __attribute__((unused)) inline void tcg_out16(TCGContext *s, uint16_t v)
141 {
142     if (TCG_TARGET_INSN_UNIT_SIZE == 2) {
143         *s->code_ptr++ = v;
144     } else {
145         tcg_insn_unit *p = s->code_ptr;
146         memcpy(p, &v, sizeof(v));
147         s->code_ptr = p + (2 / TCG_TARGET_INSN_UNIT_SIZE);
148     }
149 }
150 
151 static __attribute__((unused)) inline void tcg_patch16(tcg_insn_unit *p,
152                                                        uint16_t v)
153 {
154     if (TCG_TARGET_INSN_UNIT_SIZE == 2) {
155         *p = v;
156     } else {
157         memcpy(p, &v, sizeof(v));
158     }
159 }
160 #endif
161 
162 #if TCG_TARGET_INSN_UNIT_SIZE <= 4
163 static __attribute__((unused)) inline void tcg_out32(TCGContext *s, uint32_t v)
164 {
165     if (TCG_TARGET_INSN_UNIT_SIZE == 4) {
166         *s->code_ptr++ = v;
167     } else {
168         tcg_insn_unit *p = s->code_ptr;
169         memcpy(p, &v, sizeof(v));
170         s->code_ptr = p + (4 / TCG_TARGET_INSN_UNIT_SIZE);
171     }
172 }
173 
174 static __attribute__((unused)) inline void tcg_patch32(tcg_insn_unit *p,
175                                                        uint32_t v)
176 {
177     if (TCG_TARGET_INSN_UNIT_SIZE == 4) {
178         *p = v;
179     } else {
180         memcpy(p, &v, sizeof(v));
181     }
182 }
183 #endif
184 
185 #if TCG_TARGET_INSN_UNIT_SIZE <= 8
186 static __attribute__((unused)) inline void tcg_out64(TCGContext *s, uint64_t v)
187 {
188     if (TCG_TARGET_INSN_UNIT_SIZE == 8) {
189         *s->code_ptr++ = v;
190     } else {
191         tcg_insn_unit *p = s->code_ptr;
192         memcpy(p, &v, sizeof(v));
193         s->code_ptr = p + (8 / TCG_TARGET_INSN_UNIT_SIZE);
194     }
195 }
196 
197 static __attribute__((unused)) inline void tcg_patch64(tcg_insn_unit *p,
198                                                        uint64_t v)
199 {
200     if (TCG_TARGET_INSN_UNIT_SIZE == 8) {
201         *p = v;
202     } else {
203         memcpy(p, &v, sizeof(v));
204     }
205 }
206 #endif
207 
208 /* label relocation processing */
209 
210 static void tcg_out_reloc(TCGContext *s, tcg_insn_unit *code_ptr, int type,
211                           int label_index, intptr_t addend)
212 {
213     TCGLabel *l;
214     TCGRelocation *r;
215 
216     l = &s->labels[label_index];
217     if (l->has_value) {
218         /* FIXME: This may break relocations on RISC targets that
219            modify instruction fields in place.  The caller may not have
220            written the initial value.  */
221         patch_reloc(code_ptr, type, l->u.value, addend);
222     } else {
223         /* add a new relocation entry */
224         r = tcg_malloc(sizeof(TCGRelocation));
225         r->type = type;
226         r->ptr = code_ptr;
227         r->addend = addend;
228         r->next = l->u.first_reloc;
229         l->u.first_reloc = r;
230     }
231 }
232 
233 static void tcg_out_label(TCGContext *s, int label_index, tcg_insn_unit *ptr)
234 {
235     TCGLabel *l = &s->labels[label_index];
236     intptr_t value = (intptr_t)ptr;
237     TCGRelocation *r;
238 
239     assert(!l->has_value);
240 
241     for (r = l->u.first_reloc; r != NULL; r = r->next) {
242         patch_reloc(r->ptr, r->type, value, r->addend);
243     }
244 
245     l->has_value = 1;
246     l->u.value_ptr = ptr;
247 }
248 
249 int gen_new_label(void)
250 {
251     TCGContext *s = &tcg_ctx;
252     int idx;
253     TCGLabel *l;
254 
255     if (s->nb_labels >= TCG_MAX_LABELS)
256         tcg_abort();
257     idx = s->nb_labels++;
258     l = &s->labels[idx];
259     l->has_value = 0;
260     l->u.first_reloc = NULL;
261     return idx;
262 }
263 
264 #include "tcg-target.c"
265 
266 /* pool based memory allocation */
267 void *tcg_malloc_internal(TCGContext *s, int size)
268 {
269     TCGPool *p;
270     int pool_size;
271 
272     if (size > TCG_POOL_CHUNK_SIZE) {
273         /* big malloc: insert a new pool (XXX: could optimize) */
274         p = g_malloc(sizeof(TCGPool) + size);
275         p->size = size;
276         p->next = s->pool_first_large;
277         s->pool_first_large = p;
278         return p->data;
279     } else {
280         p = s->pool_current;
281         if (!p) {
282             p = s->pool_first;
283             if (!p)
284                 goto new_pool;
285         } else {
286             if (!p->next) {
287             new_pool:
288                 pool_size = TCG_POOL_CHUNK_SIZE;
289                 p = g_malloc(sizeof(TCGPool) + pool_size);
290                 p->size = pool_size;
291                 p->next = NULL;
292                 if (s->pool_current)
293                     s->pool_current->next = p;
294                 else
295                     s->pool_first = p;
296             } else {
297                 p = p->next;
298             }
299         }
300     }
301     s->pool_current = p;
302     s->pool_cur = p->data + size;
303     s->pool_end = p->data + p->size;
304     return p->data;
305 }
306 
307 void tcg_pool_reset(TCGContext *s)
308 {
309     TCGPool *p, *t;
310     for (p = s->pool_first_large; p; p = t) {
311         t = p->next;
312         g_free(p);
313     }
314     s->pool_first_large = NULL;
315     s->pool_cur = s->pool_end = NULL;
316     s->pool_current = NULL;
317 }
318 
319 typedef struct TCGHelperInfo {
320     void *func;
321     const char *name;
322     unsigned flags;
323     unsigned sizemask;
324 } TCGHelperInfo;
325 
326 #include "exec/helper-proto.h"
327 
328 static const TCGHelperInfo all_helpers[] = {
329 #include "exec/helper-tcg.h"
330 };
331 
332 void tcg_context_init(TCGContext *s)
333 {
334     int op, total_args, n, i;
335     TCGOpDef *def;
336     TCGArgConstraint *args_ct;
337     int *sorted_args;
338     GHashTable *helper_table;
339 
340     memset(s, 0, sizeof(*s));
341     s->nb_globals = 0;
342 
343     /* Count total number of arguments and allocate the corresponding
344        space */
345     total_args = 0;
346     for(op = 0; op < NB_OPS; op++) {
347         def = &tcg_op_defs[op];
348         n = def->nb_iargs + def->nb_oargs;
349         total_args += n;
350     }
351 
352     args_ct = g_malloc(sizeof(TCGArgConstraint) * total_args);
353     sorted_args = g_malloc(sizeof(int) * total_args);
354 
355     for(op = 0; op < NB_OPS; op++) {
356         def = &tcg_op_defs[op];
357         def->args_ct = args_ct;
358         def->sorted_args = sorted_args;
359         n = def->nb_iargs + def->nb_oargs;
360         sorted_args += n;
361         args_ct += n;
362     }
363 
364     /* Register helpers.  */
365     /* Use g_direct_hash/equal for direct pointer comparisons on func.  */
366     s->helpers = helper_table = g_hash_table_new(NULL, NULL);
367 
368     for (i = 0; i < ARRAY_SIZE(all_helpers); ++i) {
369         g_hash_table_insert(helper_table, (gpointer)all_helpers[i].func,
370                             (gpointer)&all_helpers[i]);
371     }
372 
373     tcg_target_init(s);
374 }
375 
376 void tcg_prologue_init(TCGContext *s)
377 {
378     /* init global prologue and epilogue */
379     s->code_buf = s->code_gen_prologue;
380     s->code_ptr = s->code_buf;
381     tcg_target_qemu_prologue(s);
382     flush_icache_range((uintptr_t)s->code_buf, (uintptr_t)s->code_ptr);
383 
384 #ifdef DEBUG_DISAS
385     if (qemu_loglevel_mask(CPU_LOG_TB_OUT_ASM)) {
386         size_t size = tcg_current_code_size(s);
387         qemu_log("PROLOGUE: [size=%zu]\n", size);
388         log_disas(s->code_buf, size);
389         qemu_log("\n");
390         qemu_log_flush();
391     }
392 #endif
393 }
394 
395 void tcg_set_frame(TCGContext *s, int reg, intptr_t start, intptr_t size)
396 {
397     s->frame_start = start;
398     s->frame_end = start + size;
399     s->frame_reg = reg;
400 }
401 
402 void tcg_func_start(TCGContext *s)
403 {
404     tcg_pool_reset(s);
405     s->nb_temps = s->nb_globals;
406 
407     /* No temps have been previously allocated for size or locality.  */
408     memset(s->free_temps, 0, sizeof(s->free_temps));
409 
410     s->nb_labels = 0;
411     s->current_frame_offset = s->frame_start;
412 
413 #ifdef CONFIG_DEBUG_TCG
414     s->goto_tb_issue_mask = 0;
415 #endif
416 
417     s->gen_first_op_idx = 0;
418     s->gen_last_op_idx = -1;
419     s->gen_next_op_idx = 0;
420     s->gen_next_parm_idx = 0;
421 
422     s->be = tcg_malloc(sizeof(TCGBackendData));
423 }
424 
425 static inline void tcg_temp_alloc(TCGContext *s, int n)
426 {
427     if (n > TCG_MAX_TEMPS)
428         tcg_abort();
429 }
430 
431 static inline int tcg_global_reg_new_internal(TCGType type, int reg,
432                                               const char *name)
433 {
434     TCGContext *s = &tcg_ctx;
435     TCGTemp *ts;
436     int idx;
437 
438 #if TCG_TARGET_REG_BITS == 32
439     if (type != TCG_TYPE_I32)
440         tcg_abort();
441 #endif
442     if (tcg_regset_test_reg(s->reserved_regs, reg))
443         tcg_abort();
444     idx = s->nb_globals;
445     tcg_temp_alloc(s, s->nb_globals + 1);
446     ts = &s->temps[s->nb_globals];
447     ts->base_type = type;
448     ts->type = type;
449     ts->fixed_reg = 1;
450     ts->reg = reg;
451     ts->name = name;
452     s->nb_globals++;
453     tcg_regset_set_reg(s->reserved_regs, reg);
454     return idx;
455 }
456 
457 TCGv_i32 tcg_global_reg_new_i32(int reg, const char *name)
458 {
459     int idx;
460 
461     idx = tcg_global_reg_new_internal(TCG_TYPE_I32, reg, name);
462     return MAKE_TCGV_I32(idx);
463 }
464 
465 TCGv_i64 tcg_global_reg_new_i64(int reg, const char *name)
466 {
467     int idx;
468 
469     idx = tcg_global_reg_new_internal(TCG_TYPE_I64, reg, name);
470     return MAKE_TCGV_I64(idx);
471 }
472 
473 static inline int tcg_global_mem_new_internal(TCGType type, int reg,
474                                               intptr_t offset,
475                                               const char *name)
476 {
477     TCGContext *s = &tcg_ctx;
478     TCGTemp *ts;
479     int idx;
480 
481     idx = s->nb_globals;
482 #if TCG_TARGET_REG_BITS == 32
483     if (type == TCG_TYPE_I64) {
484         char buf[64];
485         tcg_temp_alloc(s, s->nb_globals + 2);
486         ts = &s->temps[s->nb_globals];
487         ts->base_type = type;
488         ts->type = TCG_TYPE_I32;
489         ts->fixed_reg = 0;
490         ts->mem_allocated = 1;
491         ts->mem_reg = reg;
492 #ifdef HOST_WORDS_BIGENDIAN
493         ts->mem_offset = offset + 4;
494 #else
495         ts->mem_offset = offset;
496 #endif
497         pstrcpy(buf, sizeof(buf), name);
498         pstrcat(buf, sizeof(buf), "_0");
499         ts->name = strdup(buf);
500         ts++;
501 
502         ts->base_type = type;
503         ts->type = TCG_TYPE_I32;
504         ts->fixed_reg = 0;
505         ts->mem_allocated = 1;
506         ts->mem_reg = reg;
507 #ifdef HOST_WORDS_BIGENDIAN
508         ts->mem_offset = offset;
509 #else
510         ts->mem_offset = offset + 4;
511 #endif
512         pstrcpy(buf, sizeof(buf), name);
513         pstrcat(buf, sizeof(buf), "_1");
514         ts->name = strdup(buf);
515 
516         s->nb_globals += 2;
517     } else
518 #endif
519     {
520         tcg_temp_alloc(s, s->nb_globals + 1);
521         ts = &s->temps[s->nb_globals];
522         ts->base_type = type;
523         ts->type = type;
524         ts->fixed_reg = 0;
525         ts->mem_allocated = 1;
526         ts->mem_reg = reg;
527         ts->mem_offset = offset;
528         ts->name = name;
529         s->nb_globals++;
530     }
531     return idx;
532 }
533 
534 TCGv_i32 tcg_global_mem_new_i32(int reg, intptr_t offset, const char *name)
535 {
536     int idx = tcg_global_mem_new_internal(TCG_TYPE_I32, reg, offset, name);
537     return MAKE_TCGV_I32(idx);
538 }
539 
540 TCGv_i64 tcg_global_mem_new_i64(int reg, intptr_t offset, const char *name)
541 {
542     int idx = tcg_global_mem_new_internal(TCG_TYPE_I64, reg, offset, name);
543     return MAKE_TCGV_I64(idx);
544 }
545 
546 static inline int tcg_temp_new_internal(TCGType type, int temp_local)
547 {
548     TCGContext *s = &tcg_ctx;
549     TCGTemp *ts;
550     int idx, k;
551 
552     k = type + (temp_local ? TCG_TYPE_COUNT : 0);
553     idx = find_first_bit(s->free_temps[k].l, TCG_MAX_TEMPS);
554     if (idx < TCG_MAX_TEMPS) {
555         /* There is already an available temp with the right type.  */
556         clear_bit(idx, s->free_temps[k].l);
557 
558         ts = &s->temps[idx];
559         ts->temp_allocated = 1;
560         assert(ts->base_type == type);
561         assert(ts->temp_local == temp_local);
562     } else {
563         idx = s->nb_temps;
564 #if TCG_TARGET_REG_BITS == 32
565         if (type == TCG_TYPE_I64) {
566             tcg_temp_alloc(s, s->nb_temps + 2);
567             ts = &s->temps[s->nb_temps];
568             ts->base_type = type;
569             ts->type = TCG_TYPE_I32;
570             ts->temp_allocated = 1;
571             ts->temp_local = temp_local;
572             ts->name = NULL;
573             ts++;
574             ts->base_type = type;
575             ts->type = TCG_TYPE_I32;
576             ts->temp_allocated = 1;
577             ts->temp_local = temp_local;
578             ts->name = NULL;
579             s->nb_temps += 2;
580         } else
581 #endif
582         {
583             tcg_temp_alloc(s, s->nb_temps + 1);
584             ts = &s->temps[s->nb_temps];
585             ts->base_type = type;
586             ts->type = type;
587             ts->temp_allocated = 1;
588             ts->temp_local = temp_local;
589             ts->name = NULL;
590             s->nb_temps++;
591         }
592     }
593 
594 #if defined(CONFIG_DEBUG_TCG)
595     s->temps_in_use++;
596 #endif
597     return idx;
598 }
599 
600 TCGv_i32 tcg_temp_new_internal_i32(int temp_local)
601 {
602     int idx;
603 
604     idx = tcg_temp_new_internal(TCG_TYPE_I32, temp_local);
605     return MAKE_TCGV_I32(idx);
606 }
607 
608 TCGv_i64 tcg_temp_new_internal_i64(int temp_local)
609 {
610     int idx;
611 
612     idx = tcg_temp_new_internal(TCG_TYPE_I64, temp_local);
613     return MAKE_TCGV_I64(idx);
614 }
615 
616 static void tcg_temp_free_internal(int idx)
617 {
618     TCGContext *s = &tcg_ctx;
619     TCGTemp *ts;
620     int k;
621 
622 #if defined(CONFIG_DEBUG_TCG)
623     s->temps_in_use--;
624     if (s->temps_in_use < 0) {
625         fprintf(stderr, "More temporaries freed than allocated!\n");
626     }
627 #endif
628 
629     assert(idx >= s->nb_globals && idx < s->nb_temps);
630     ts = &s->temps[idx];
631     assert(ts->temp_allocated != 0);
632     ts->temp_allocated = 0;
633 
634     k = ts->base_type + (ts->temp_local ? TCG_TYPE_COUNT : 0);
635     set_bit(idx, s->free_temps[k].l);
636 }
637 
638 void tcg_temp_free_i32(TCGv_i32 arg)
639 {
640     tcg_temp_free_internal(GET_TCGV_I32(arg));
641 }
642 
643 void tcg_temp_free_i64(TCGv_i64 arg)
644 {
645     tcg_temp_free_internal(GET_TCGV_I64(arg));
646 }
647 
648 TCGv_i32 tcg_const_i32(int32_t val)
649 {
650     TCGv_i32 t0;
651     t0 = tcg_temp_new_i32();
652     tcg_gen_movi_i32(t0, val);
653     return t0;
654 }
655 
656 TCGv_i64 tcg_const_i64(int64_t val)
657 {
658     TCGv_i64 t0;
659     t0 = tcg_temp_new_i64();
660     tcg_gen_movi_i64(t0, val);
661     return t0;
662 }
663 
664 TCGv_i32 tcg_const_local_i32(int32_t val)
665 {
666     TCGv_i32 t0;
667     t0 = tcg_temp_local_new_i32();
668     tcg_gen_movi_i32(t0, val);
669     return t0;
670 }
671 
672 TCGv_i64 tcg_const_local_i64(int64_t val)
673 {
674     TCGv_i64 t0;
675     t0 = tcg_temp_local_new_i64();
676     tcg_gen_movi_i64(t0, val);
677     return t0;
678 }
679 
680 #if defined(CONFIG_DEBUG_TCG)
681 void tcg_clear_temp_count(void)
682 {
683     TCGContext *s = &tcg_ctx;
684     s->temps_in_use = 0;
685 }
686 
687 int tcg_check_temp_count(void)
688 {
689     TCGContext *s = &tcg_ctx;
690     if (s->temps_in_use) {
691         /* Clear the count so that we don't give another
692          * warning immediately next time around.
693          */
694         s->temps_in_use = 0;
695         return 1;
696     }
697     return 0;
698 }
699 #endif
700 
701 /* Note: we convert the 64 bit args to 32 bit and do some alignment
702    and endian swap. Maybe it would be better to do the alignment
703    and endian swap in tcg_reg_alloc_call(). */
704 void tcg_gen_callN(TCGContext *s, void *func, TCGArg ret,
705                    int nargs, TCGArg *args)
706 {
707     int i, real_args, nb_rets, pi, pi_first;
708     unsigned sizemask, flags;
709     TCGHelperInfo *info;
710 
711     info = g_hash_table_lookup(s->helpers, (gpointer)func);
712     flags = info->flags;
713     sizemask = info->sizemask;
714 
715 #if defined(__sparc__) && !defined(__arch64__) \
716     && !defined(CONFIG_TCG_INTERPRETER)
717     /* We have 64-bit values in one register, but need to pass as two
718        separate parameters.  Split them.  */
719     int orig_sizemask = sizemask;
720     int orig_nargs = nargs;
721     TCGv_i64 retl, reth;
722 
723     TCGV_UNUSED_I64(retl);
724     TCGV_UNUSED_I64(reth);
725     if (sizemask != 0) {
726         TCGArg *split_args = __builtin_alloca(sizeof(TCGArg) * nargs * 2);
727         for (i = real_args = 0; i < nargs; ++i) {
728             int is_64bit = sizemask & (1 << (i+1)*2);
729             if (is_64bit) {
730                 TCGv_i64 orig = MAKE_TCGV_I64(args[i]);
731                 TCGv_i32 h = tcg_temp_new_i32();
732                 TCGv_i32 l = tcg_temp_new_i32();
733                 tcg_gen_extr_i64_i32(l, h, orig);
734                 split_args[real_args++] = GET_TCGV_I32(h);
735                 split_args[real_args++] = GET_TCGV_I32(l);
736             } else {
737                 split_args[real_args++] = args[i];
738             }
739         }
740         nargs = real_args;
741         args = split_args;
742         sizemask = 0;
743     }
744 #elif defined(TCG_TARGET_EXTEND_ARGS) && TCG_TARGET_REG_BITS == 64
745     for (i = 0; i < nargs; ++i) {
746         int is_64bit = sizemask & (1 << (i+1)*2);
747         int is_signed = sizemask & (2 << (i+1)*2);
748         if (!is_64bit) {
749             TCGv_i64 temp = tcg_temp_new_i64();
750             TCGv_i64 orig = MAKE_TCGV_I64(args[i]);
751             if (is_signed) {
752                 tcg_gen_ext32s_i64(temp, orig);
753             } else {
754                 tcg_gen_ext32u_i64(temp, orig);
755             }
756             args[i] = GET_TCGV_I64(temp);
757         }
758     }
759 #endif /* TCG_TARGET_EXTEND_ARGS */
760 
761     pi_first = pi = s->gen_next_parm_idx;
762     if (ret != TCG_CALL_DUMMY_ARG) {
763 #if defined(__sparc__) && !defined(__arch64__) \
764     && !defined(CONFIG_TCG_INTERPRETER)
765         if (orig_sizemask & 1) {
766             /* The 32-bit ABI is going to return the 64-bit value in
767                the %o0/%o1 register pair.  Prepare for this by using
768                two return temporaries, and reassemble below.  */
769             retl = tcg_temp_new_i64();
770             reth = tcg_temp_new_i64();
771             s->gen_opparam_buf[pi++] = GET_TCGV_I64(reth);
772             s->gen_opparam_buf[pi++] = GET_TCGV_I64(retl);
773             nb_rets = 2;
774         } else {
775             s->gen_opparam_buf[pi++] = ret;
776             nb_rets = 1;
777         }
778 #else
779         if (TCG_TARGET_REG_BITS < 64 && (sizemask & 1)) {
780 #ifdef HOST_WORDS_BIGENDIAN
781             s->gen_opparam_buf[pi++] = ret + 1;
782             s->gen_opparam_buf[pi++] = ret;
783 #else
784             s->gen_opparam_buf[pi++] = ret;
785             s->gen_opparam_buf[pi++] = ret + 1;
786 #endif
787             nb_rets = 2;
788         } else {
789             s->gen_opparam_buf[pi++] = ret;
790             nb_rets = 1;
791         }
792 #endif
793     } else {
794         nb_rets = 0;
795     }
796     real_args = 0;
797     for (i = 0; i < nargs; i++) {
798         int is_64bit = sizemask & (1 << (i+1)*2);
799         if (TCG_TARGET_REG_BITS < 64 && is_64bit) {
800 #ifdef TCG_TARGET_CALL_ALIGN_ARGS
801             /* some targets want aligned 64 bit args */
802             if (real_args & 1) {
803                 s->gen_opparam_buf[pi++] = TCG_CALL_DUMMY_ARG;
804                 real_args++;
805             }
806 #endif
807 	    /* If stack grows up, then we will be placing successive
808 	       arguments at lower addresses, which means we need to
809 	       reverse the order compared to how we would normally
810 	       treat either big or little-endian.  For those arguments
811 	       that will wind up in registers, this still works for
812 	       HPPA (the only current STACK_GROWSUP target) since the
813 	       argument registers are *also* allocated in decreasing
814 	       order.  If another such target is added, this logic may
815 	       have to get more complicated to differentiate between
816 	       stack arguments and register arguments.  */
817 #if defined(HOST_WORDS_BIGENDIAN) != defined(TCG_TARGET_STACK_GROWSUP)
818             s->gen_opparam_buf[pi++] = args[i] + 1;
819             s->gen_opparam_buf[pi++] = args[i];
820 #else
821             s->gen_opparam_buf[pi++] = args[i];
822             s->gen_opparam_buf[pi++] = args[i] + 1;
823 #endif
824             real_args += 2;
825             continue;
826         }
827 
828         s->gen_opparam_buf[pi++] = args[i];
829         real_args++;
830     }
831     s->gen_opparam_buf[pi++] = (uintptr_t)func;
832     s->gen_opparam_buf[pi++] = flags;
833 
834     i = s->gen_next_op_idx;
835     tcg_debug_assert(i < OPC_BUF_SIZE);
836     tcg_debug_assert(pi <= OPPARAM_BUF_SIZE);
837 
838     /* Set links for sequential allocation during translation.  */
839     s->gen_op_buf[i] = (TCGOp){
840         .opc = INDEX_op_call,
841         .callo = nb_rets,
842         .calli = real_args,
843         .args = pi_first,
844         .prev = i - 1,
845         .next = i + 1
846     };
847 
848     /* Make sure the calli field didn't overflow.  */
849     tcg_debug_assert(s->gen_op_buf[i].calli == real_args);
850 
851     s->gen_last_op_idx = i;
852     s->gen_next_op_idx = i + 1;
853     s->gen_next_parm_idx = pi;
854 
855 #if defined(__sparc__) && !defined(__arch64__) \
856     && !defined(CONFIG_TCG_INTERPRETER)
857     /* Free all of the parts we allocated above.  */
858     for (i = real_args = 0; i < orig_nargs; ++i) {
859         int is_64bit = orig_sizemask & (1 << (i+1)*2);
860         if (is_64bit) {
861             TCGv_i32 h = MAKE_TCGV_I32(args[real_args++]);
862             TCGv_i32 l = MAKE_TCGV_I32(args[real_args++]);
863             tcg_temp_free_i32(h);
864             tcg_temp_free_i32(l);
865         } else {
866             real_args++;
867         }
868     }
869     if (orig_sizemask & 1) {
870         /* The 32-bit ABI returned two 32-bit pieces.  Re-assemble them.
871            Note that describing these as TCGv_i64 eliminates an unnecessary
872            zero-extension that tcg_gen_concat_i32_i64 would create.  */
873         tcg_gen_concat32_i64(MAKE_TCGV_I64(ret), retl, reth);
874         tcg_temp_free_i64(retl);
875         tcg_temp_free_i64(reth);
876     }
877 #elif defined(TCG_TARGET_EXTEND_ARGS) && TCG_TARGET_REG_BITS == 64
878     for (i = 0; i < nargs; ++i) {
879         int is_64bit = sizemask & (1 << (i+1)*2);
880         if (!is_64bit) {
881             TCGv_i64 temp = MAKE_TCGV_I64(args[i]);
882             tcg_temp_free_i64(temp);
883         }
884     }
885 #endif /* TCG_TARGET_EXTEND_ARGS */
886 }
887 
888 static void tcg_reg_alloc_start(TCGContext *s)
889 {
890     int i;
891     TCGTemp *ts;
892     for(i = 0; i < s->nb_globals; i++) {
893         ts = &s->temps[i];
894         if (ts->fixed_reg) {
895             ts->val_type = TEMP_VAL_REG;
896         } else {
897             ts->val_type = TEMP_VAL_MEM;
898         }
899     }
900     for(i = s->nb_globals; i < s->nb_temps; i++) {
901         ts = &s->temps[i];
902         if (ts->temp_local) {
903             ts->val_type = TEMP_VAL_MEM;
904         } else {
905             ts->val_type = TEMP_VAL_DEAD;
906         }
907         ts->mem_allocated = 0;
908         ts->fixed_reg = 0;
909     }
910     for(i = 0; i < TCG_TARGET_NB_REGS; i++) {
911         s->reg_to_temp[i] = -1;
912     }
913 }
914 
915 static char *tcg_get_arg_str_idx(TCGContext *s, char *buf, int buf_size,
916                                  int idx)
917 {
918     TCGTemp *ts;
919 
920     assert(idx >= 0 && idx < s->nb_temps);
921     ts = &s->temps[idx];
922     if (idx < s->nb_globals) {
923         pstrcpy(buf, buf_size, ts->name);
924     } else {
925         if (ts->temp_local)
926             snprintf(buf, buf_size, "loc%d", idx - s->nb_globals);
927         else
928             snprintf(buf, buf_size, "tmp%d", idx - s->nb_globals);
929     }
930     return buf;
931 }
932 
933 char *tcg_get_arg_str_i32(TCGContext *s, char *buf, int buf_size, TCGv_i32 arg)
934 {
935     return tcg_get_arg_str_idx(s, buf, buf_size, GET_TCGV_I32(arg));
936 }
937 
938 char *tcg_get_arg_str_i64(TCGContext *s, char *buf, int buf_size, TCGv_i64 arg)
939 {
940     return tcg_get_arg_str_idx(s, buf, buf_size, GET_TCGV_I64(arg));
941 }
942 
943 /* Find helper name.  */
944 static inline const char *tcg_find_helper(TCGContext *s, uintptr_t val)
945 {
946     const char *ret = NULL;
947     if (s->helpers) {
948         TCGHelperInfo *info = g_hash_table_lookup(s->helpers, (gpointer)val);
949         if (info) {
950             ret = info->name;
951         }
952     }
953     return ret;
954 }
955 
956 static const char * const cond_name[] =
957 {
958     [TCG_COND_NEVER] = "never",
959     [TCG_COND_ALWAYS] = "always",
960     [TCG_COND_EQ] = "eq",
961     [TCG_COND_NE] = "ne",
962     [TCG_COND_LT] = "lt",
963     [TCG_COND_GE] = "ge",
964     [TCG_COND_LE] = "le",
965     [TCG_COND_GT] = "gt",
966     [TCG_COND_LTU] = "ltu",
967     [TCG_COND_GEU] = "geu",
968     [TCG_COND_LEU] = "leu",
969     [TCG_COND_GTU] = "gtu"
970 };
971 
972 static const char * const ldst_name[] =
973 {
974     [MO_UB]   = "ub",
975     [MO_SB]   = "sb",
976     [MO_LEUW] = "leuw",
977     [MO_LESW] = "lesw",
978     [MO_LEUL] = "leul",
979     [MO_LESL] = "lesl",
980     [MO_LEQ]  = "leq",
981     [MO_BEUW] = "beuw",
982     [MO_BESW] = "besw",
983     [MO_BEUL] = "beul",
984     [MO_BESL] = "besl",
985     [MO_BEQ]  = "beq",
986 };
987 
988 void tcg_dump_ops(TCGContext *s)
989 {
990     char buf[128];
991     TCGOp *op;
992     int oi;
993 
994     for (oi = s->gen_first_op_idx; oi >= 0; oi = op->next) {
995         int i, k, nb_oargs, nb_iargs, nb_cargs;
996         const TCGOpDef *def;
997         const TCGArg *args;
998         TCGOpcode c;
999 
1000         op = &s->gen_op_buf[oi];
1001         c = op->opc;
1002         def = &tcg_op_defs[c];
1003         args = &s->gen_opparam_buf[op->args];
1004 
1005         if (c == INDEX_op_debug_insn_start) {
1006             uint64_t pc;
1007 #if TARGET_LONG_BITS > TCG_TARGET_REG_BITS
1008             pc = ((uint64_t)args[1] << 32) | args[0];
1009 #else
1010             pc = args[0];
1011 #endif
1012             if (oi != s->gen_first_op_idx) {
1013                 qemu_log("\n");
1014             }
1015             qemu_log(" ---- 0x%" PRIx64, pc);
1016         } else if (c == INDEX_op_call) {
1017             /* variable number of arguments */
1018             nb_oargs = op->callo;
1019             nb_iargs = op->calli;
1020             nb_cargs = def->nb_cargs;
1021 
1022             /* function name, flags, out args */
1023             qemu_log(" %s %s,$0x%" TCG_PRIlx ",$%d", def->name,
1024                      tcg_find_helper(s, args[nb_oargs + nb_iargs]),
1025                      args[nb_oargs + nb_iargs + 1], nb_oargs);
1026             for (i = 0; i < nb_oargs; i++) {
1027                 qemu_log(",%s", tcg_get_arg_str_idx(s, buf, sizeof(buf),
1028                                                    args[i]));
1029             }
1030             for (i = 0; i < nb_iargs; i++) {
1031                 TCGArg arg = args[nb_oargs + i];
1032                 const char *t = "<dummy>";
1033                 if (arg != TCG_CALL_DUMMY_ARG) {
1034                     t = tcg_get_arg_str_idx(s, buf, sizeof(buf), arg);
1035                 }
1036                 qemu_log(",%s", t);
1037             }
1038         } else {
1039             qemu_log(" %s ", def->name);
1040 
1041             nb_oargs = def->nb_oargs;
1042             nb_iargs = def->nb_iargs;
1043             nb_cargs = def->nb_cargs;
1044 
1045             k = 0;
1046             for (i = 0; i < nb_oargs; i++) {
1047                 if (k != 0) {
1048                     qemu_log(",");
1049                 }
1050                 qemu_log("%s", tcg_get_arg_str_idx(s, buf, sizeof(buf),
1051                                                    args[k++]));
1052             }
1053             for (i = 0; i < nb_iargs; i++) {
1054                 if (k != 0) {
1055                     qemu_log(",");
1056                 }
1057                 qemu_log("%s", tcg_get_arg_str_idx(s, buf, sizeof(buf),
1058                                                    args[k++]));
1059             }
1060             switch (c) {
1061             case INDEX_op_brcond_i32:
1062             case INDEX_op_setcond_i32:
1063             case INDEX_op_movcond_i32:
1064             case INDEX_op_brcond2_i32:
1065             case INDEX_op_setcond2_i32:
1066             case INDEX_op_brcond_i64:
1067             case INDEX_op_setcond_i64:
1068             case INDEX_op_movcond_i64:
1069                 if (args[k] < ARRAY_SIZE(cond_name) && cond_name[args[k]]) {
1070                     qemu_log(",%s", cond_name[args[k++]]);
1071                 } else {
1072                     qemu_log(",$0x%" TCG_PRIlx, args[k++]);
1073                 }
1074                 i = 1;
1075                 break;
1076             case INDEX_op_qemu_ld_i32:
1077             case INDEX_op_qemu_st_i32:
1078             case INDEX_op_qemu_ld_i64:
1079             case INDEX_op_qemu_st_i64:
1080                 if (args[k] < ARRAY_SIZE(ldst_name) && ldst_name[args[k]]) {
1081                     qemu_log(",%s", ldst_name[args[k++]]);
1082                 } else {
1083                     qemu_log(",$0x%" TCG_PRIlx, args[k++]);
1084                 }
1085                 i = 1;
1086                 break;
1087             default:
1088                 i = 0;
1089                 break;
1090             }
1091             for (; i < nb_cargs; i++) {
1092                 if (k != 0) {
1093                     qemu_log(",");
1094                 }
1095                 qemu_log("$0x%" TCG_PRIlx, args[k++]);
1096             }
1097         }
1098         qemu_log("\n");
1099     }
1100 }
1101 
1102 /* we give more priority to constraints with less registers */
1103 static int get_constraint_priority(const TCGOpDef *def, int k)
1104 {
1105     const TCGArgConstraint *arg_ct;
1106 
1107     int i, n;
1108     arg_ct = &def->args_ct[k];
1109     if (arg_ct->ct & TCG_CT_ALIAS) {
1110         /* an alias is equivalent to a single register */
1111         n = 1;
1112     } else {
1113         if (!(arg_ct->ct & TCG_CT_REG))
1114             return 0;
1115         n = 0;
1116         for(i = 0; i < TCG_TARGET_NB_REGS; i++) {
1117             if (tcg_regset_test_reg(arg_ct->u.regs, i))
1118                 n++;
1119         }
1120     }
1121     return TCG_TARGET_NB_REGS - n + 1;
1122 }
1123 
1124 /* sort from highest priority to lowest */
1125 static void sort_constraints(TCGOpDef *def, int start, int n)
1126 {
1127     int i, j, p1, p2, tmp;
1128 
1129     for(i = 0; i < n; i++)
1130         def->sorted_args[start + i] = start + i;
1131     if (n <= 1)
1132         return;
1133     for(i = 0; i < n - 1; i++) {
1134         for(j = i + 1; j < n; j++) {
1135             p1 = get_constraint_priority(def, def->sorted_args[start + i]);
1136             p2 = get_constraint_priority(def, def->sorted_args[start + j]);
1137             if (p1 < p2) {
1138                 tmp = def->sorted_args[start + i];
1139                 def->sorted_args[start + i] = def->sorted_args[start + j];
1140                 def->sorted_args[start + j] = tmp;
1141             }
1142         }
1143     }
1144 }
1145 
1146 void tcg_add_target_add_op_defs(const TCGTargetOpDef *tdefs)
1147 {
1148     TCGOpcode op;
1149     TCGOpDef *def;
1150     const char *ct_str;
1151     int i, nb_args;
1152 
1153     for(;;) {
1154         if (tdefs->op == (TCGOpcode)-1)
1155             break;
1156         op = tdefs->op;
1157         assert((unsigned)op < NB_OPS);
1158         def = &tcg_op_defs[op];
1159 #if defined(CONFIG_DEBUG_TCG)
1160         /* Duplicate entry in op definitions? */
1161         assert(!def->used);
1162         def->used = 1;
1163 #endif
1164         nb_args = def->nb_iargs + def->nb_oargs;
1165         for(i = 0; i < nb_args; i++) {
1166             ct_str = tdefs->args_ct_str[i];
1167             /* Incomplete TCGTargetOpDef entry? */
1168             assert(ct_str != NULL);
1169             tcg_regset_clear(def->args_ct[i].u.regs);
1170             def->args_ct[i].ct = 0;
1171             if (ct_str[0] >= '0' && ct_str[0] <= '9') {
1172                 int oarg;
1173                 oarg = ct_str[0] - '0';
1174                 assert(oarg < def->nb_oargs);
1175                 assert(def->args_ct[oarg].ct & TCG_CT_REG);
1176                 /* TCG_CT_ALIAS is for the output arguments. The input
1177                    argument is tagged with TCG_CT_IALIAS. */
1178                 def->args_ct[i] = def->args_ct[oarg];
1179                 def->args_ct[oarg].ct = TCG_CT_ALIAS;
1180                 def->args_ct[oarg].alias_index = i;
1181                 def->args_ct[i].ct |= TCG_CT_IALIAS;
1182                 def->args_ct[i].alias_index = oarg;
1183             } else {
1184                 for(;;) {
1185                     if (*ct_str == '\0')
1186                         break;
1187                     switch(*ct_str) {
1188                     case 'i':
1189                         def->args_ct[i].ct |= TCG_CT_CONST;
1190                         ct_str++;
1191                         break;
1192                     default:
1193                         if (target_parse_constraint(&def->args_ct[i], &ct_str) < 0) {
1194                             fprintf(stderr, "Invalid constraint '%s' for arg %d of operation '%s'\n",
1195                                     ct_str, i, def->name);
1196                             exit(1);
1197                         }
1198                     }
1199                 }
1200             }
1201         }
1202 
1203         /* TCGTargetOpDef entry with too much information? */
1204         assert(i == TCG_MAX_OP_ARGS || tdefs->args_ct_str[i] == NULL);
1205 
1206         /* sort the constraints (XXX: this is just an heuristic) */
1207         sort_constraints(def, 0, def->nb_oargs);
1208         sort_constraints(def, def->nb_oargs, def->nb_iargs);
1209 
1210 #if 0
1211         {
1212             int i;
1213 
1214             printf("%s: sorted=", def->name);
1215             for(i = 0; i < def->nb_oargs + def->nb_iargs; i++)
1216                 printf(" %d", def->sorted_args[i]);
1217             printf("\n");
1218         }
1219 #endif
1220         tdefs++;
1221     }
1222 
1223 #if defined(CONFIG_DEBUG_TCG)
1224     i = 0;
1225     for (op = 0; op < ARRAY_SIZE(tcg_op_defs); op++) {
1226         const TCGOpDef *def = &tcg_op_defs[op];
1227         if (def->flags & TCG_OPF_NOT_PRESENT) {
1228             /* Wrong entry in op definitions? */
1229             if (def->used) {
1230                 fprintf(stderr, "Invalid op definition for %s\n", def->name);
1231                 i = 1;
1232             }
1233         } else {
1234             /* Missing entry in op definitions? */
1235             if (!def->used) {
1236                 fprintf(stderr, "Missing op definition for %s\n", def->name);
1237                 i = 1;
1238             }
1239         }
1240     }
1241     if (i == 1) {
1242         tcg_abort();
1243     }
1244 #endif
1245 }
1246 
1247 void tcg_op_remove(TCGContext *s, TCGOp *op)
1248 {
1249     int next = op->next;
1250     int prev = op->prev;
1251 
1252     if (next >= 0) {
1253         s->gen_op_buf[next].prev = prev;
1254     } else {
1255         s->gen_last_op_idx = prev;
1256     }
1257     if (prev >= 0) {
1258         s->gen_op_buf[prev].next = next;
1259     } else {
1260         s->gen_first_op_idx = next;
1261     }
1262 
1263     memset(op, -1, sizeof(*op));
1264 
1265 #ifdef CONFIG_PROFILER
1266     s->del_op_count++;
1267 #endif
1268 }
1269 
1270 #ifdef USE_LIVENESS_ANALYSIS
1271 /* liveness analysis: end of function: all temps are dead, and globals
1272    should be in memory. */
1273 static inline void tcg_la_func_end(TCGContext *s, uint8_t *dead_temps,
1274                                    uint8_t *mem_temps)
1275 {
1276     memset(dead_temps, 1, s->nb_temps);
1277     memset(mem_temps, 1, s->nb_globals);
1278     memset(mem_temps + s->nb_globals, 0, s->nb_temps - s->nb_globals);
1279 }
1280 
1281 /* liveness analysis: end of basic block: all temps are dead, globals
1282    and local temps should be in memory. */
1283 static inline void tcg_la_bb_end(TCGContext *s, uint8_t *dead_temps,
1284                                  uint8_t *mem_temps)
1285 {
1286     int i;
1287 
1288     memset(dead_temps, 1, s->nb_temps);
1289     memset(mem_temps, 1, s->nb_globals);
1290     for(i = s->nb_globals; i < s->nb_temps; i++) {
1291         mem_temps[i] = s->temps[i].temp_local;
1292     }
1293 }
1294 
1295 /* Liveness analysis : update the opc_dead_args array to tell if a
1296    given input arguments is dead. Instructions updating dead
1297    temporaries are removed. */
1298 static void tcg_liveness_analysis(TCGContext *s)
1299 {
1300     uint8_t *dead_temps, *mem_temps;
1301     int oi, oi_prev, nb_ops;
1302 
1303     nb_ops = s->gen_next_op_idx;
1304     s->op_dead_args = tcg_malloc(nb_ops * sizeof(uint16_t));
1305     s->op_sync_args = tcg_malloc(nb_ops * sizeof(uint8_t));
1306 
1307     dead_temps = tcg_malloc(s->nb_temps);
1308     mem_temps = tcg_malloc(s->nb_temps);
1309     tcg_la_func_end(s, dead_temps, mem_temps);
1310 
1311     for (oi = s->gen_last_op_idx; oi >= 0; oi = oi_prev) {
1312         int i, nb_iargs, nb_oargs;
1313         TCGOpcode opc_new, opc_new2;
1314         bool have_opc_new2;
1315         uint16_t dead_args;
1316         uint8_t sync_args;
1317         TCGArg arg;
1318 
1319         TCGOp * const op = &s->gen_op_buf[oi];
1320         TCGArg * const args = &s->gen_opparam_buf[op->args];
1321         TCGOpcode opc = op->opc;
1322         const TCGOpDef *def = &tcg_op_defs[opc];
1323 
1324         oi_prev = op->prev;
1325 
1326         switch (opc) {
1327         case INDEX_op_call:
1328             {
1329                 int call_flags;
1330 
1331                 nb_oargs = op->callo;
1332                 nb_iargs = op->calli;
1333                 call_flags = args[nb_oargs + nb_iargs + 1];
1334 
1335                 /* pure functions can be removed if their result is unused */
1336                 if (call_flags & TCG_CALL_NO_SIDE_EFFECTS) {
1337                     for (i = 0; i < nb_oargs; i++) {
1338                         arg = args[i];
1339                         if (!dead_temps[arg] || mem_temps[arg]) {
1340                             goto do_not_remove_call;
1341                         }
1342                     }
1343                     goto do_remove;
1344                 } else {
1345                 do_not_remove_call:
1346 
1347                     /* output args are dead */
1348                     dead_args = 0;
1349                     sync_args = 0;
1350                     for (i = 0; i < nb_oargs; i++) {
1351                         arg = args[i];
1352                         if (dead_temps[arg]) {
1353                             dead_args |= (1 << i);
1354                         }
1355                         if (mem_temps[arg]) {
1356                             sync_args |= (1 << i);
1357                         }
1358                         dead_temps[arg] = 1;
1359                         mem_temps[arg] = 0;
1360                     }
1361 
1362                     if (!(call_flags & TCG_CALL_NO_READ_GLOBALS)) {
1363                         /* globals should be synced to memory */
1364                         memset(mem_temps, 1, s->nb_globals);
1365                     }
1366                     if (!(call_flags & (TCG_CALL_NO_WRITE_GLOBALS |
1367                                         TCG_CALL_NO_READ_GLOBALS))) {
1368                         /* globals should go back to memory */
1369                         memset(dead_temps, 1, s->nb_globals);
1370                     }
1371 
1372                     /* input args are live */
1373                     for (i = nb_oargs; i < nb_iargs + nb_oargs; i++) {
1374                         arg = args[i];
1375                         if (arg != TCG_CALL_DUMMY_ARG) {
1376                             if (dead_temps[arg]) {
1377                                 dead_args |= (1 << i);
1378                             }
1379                             dead_temps[arg] = 0;
1380                         }
1381                     }
1382                     s->op_dead_args[oi] = dead_args;
1383                     s->op_sync_args[oi] = sync_args;
1384                 }
1385             }
1386             break;
1387         case INDEX_op_debug_insn_start:
1388             break;
1389         case INDEX_op_discard:
1390             /* mark the temporary as dead */
1391             dead_temps[args[0]] = 1;
1392             mem_temps[args[0]] = 0;
1393             break;
1394 
1395         case INDEX_op_add2_i32:
1396             opc_new = INDEX_op_add_i32;
1397             goto do_addsub2;
1398         case INDEX_op_sub2_i32:
1399             opc_new = INDEX_op_sub_i32;
1400             goto do_addsub2;
1401         case INDEX_op_add2_i64:
1402             opc_new = INDEX_op_add_i64;
1403             goto do_addsub2;
1404         case INDEX_op_sub2_i64:
1405             opc_new = INDEX_op_sub_i64;
1406         do_addsub2:
1407             nb_iargs = 4;
1408             nb_oargs = 2;
1409             /* Test if the high part of the operation is dead, but not
1410                the low part.  The result can be optimized to a simple
1411                add or sub.  This happens often for x86_64 guest when the
1412                cpu mode is set to 32 bit.  */
1413             if (dead_temps[args[1]] && !mem_temps[args[1]]) {
1414                 if (dead_temps[args[0]] && !mem_temps[args[0]]) {
1415                     goto do_remove;
1416                 }
1417                 /* Replace the opcode and adjust the args in place,
1418                    leaving 3 unused args at the end.  */
1419                 op->opc = opc = opc_new;
1420                 args[1] = args[2];
1421                 args[2] = args[4];
1422                 /* Fall through and mark the single-word operation live.  */
1423                 nb_iargs = 2;
1424                 nb_oargs = 1;
1425             }
1426             goto do_not_remove;
1427 
1428         case INDEX_op_mulu2_i32:
1429             opc_new = INDEX_op_mul_i32;
1430             opc_new2 = INDEX_op_muluh_i32;
1431             have_opc_new2 = TCG_TARGET_HAS_muluh_i32;
1432             goto do_mul2;
1433         case INDEX_op_muls2_i32:
1434             opc_new = INDEX_op_mul_i32;
1435             opc_new2 = INDEX_op_mulsh_i32;
1436             have_opc_new2 = TCG_TARGET_HAS_mulsh_i32;
1437             goto do_mul2;
1438         case INDEX_op_mulu2_i64:
1439             opc_new = INDEX_op_mul_i64;
1440             opc_new2 = INDEX_op_muluh_i64;
1441             have_opc_new2 = TCG_TARGET_HAS_muluh_i64;
1442             goto do_mul2;
1443         case INDEX_op_muls2_i64:
1444             opc_new = INDEX_op_mul_i64;
1445             opc_new2 = INDEX_op_mulsh_i64;
1446             have_opc_new2 = TCG_TARGET_HAS_mulsh_i64;
1447             goto do_mul2;
1448         do_mul2:
1449             nb_iargs = 2;
1450             nb_oargs = 2;
1451             if (dead_temps[args[1]] && !mem_temps[args[1]]) {
1452                 if (dead_temps[args[0]] && !mem_temps[args[0]]) {
1453                     /* Both parts of the operation are dead.  */
1454                     goto do_remove;
1455                 }
1456                 /* The high part of the operation is dead; generate the low. */
1457                 op->opc = opc = opc_new;
1458                 args[1] = args[2];
1459                 args[2] = args[3];
1460             } else if (have_opc_new2 && dead_temps[args[0]]
1461                        && !mem_temps[args[0]]) {
1462                 /* The low part of the operation is dead; generate the high. */
1463                 op->opc = opc = opc_new2;
1464                 args[0] = args[1];
1465                 args[1] = args[2];
1466                 args[2] = args[3];
1467             } else {
1468                 goto do_not_remove;
1469             }
1470             /* Mark the single-word operation live.  */
1471             nb_oargs = 1;
1472             goto do_not_remove;
1473 
1474         default:
1475             /* XXX: optimize by hardcoding common cases (e.g. triadic ops) */
1476             nb_iargs = def->nb_iargs;
1477             nb_oargs = def->nb_oargs;
1478 
1479             /* Test if the operation can be removed because all
1480                its outputs are dead. We assume that nb_oargs == 0
1481                implies side effects */
1482             if (!(def->flags & TCG_OPF_SIDE_EFFECTS) && nb_oargs != 0) {
1483                 for (i = 0; i < nb_oargs; i++) {
1484                     arg = args[i];
1485                     if (!dead_temps[arg] || mem_temps[arg]) {
1486                         goto do_not_remove;
1487                     }
1488                 }
1489             do_remove:
1490                 tcg_op_remove(s, op);
1491             } else {
1492             do_not_remove:
1493                 /* output args are dead */
1494                 dead_args = 0;
1495                 sync_args = 0;
1496                 for (i = 0; i < nb_oargs; i++) {
1497                     arg = args[i];
1498                     if (dead_temps[arg]) {
1499                         dead_args |= (1 << i);
1500                     }
1501                     if (mem_temps[arg]) {
1502                         sync_args |= (1 << i);
1503                     }
1504                     dead_temps[arg] = 1;
1505                     mem_temps[arg] = 0;
1506                 }
1507 
1508                 /* if end of basic block, update */
1509                 if (def->flags & TCG_OPF_BB_END) {
1510                     tcg_la_bb_end(s, dead_temps, mem_temps);
1511                 } else if (def->flags & TCG_OPF_SIDE_EFFECTS) {
1512                     /* globals should be synced to memory */
1513                     memset(mem_temps, 1, s->nb_globals);
1514                 }
1515 
1516                 /* input args are live */
1517                 for (i = nb_oargs; i < nb_oargs + nb_iargs; i++) {
1518                     arg = args[i];
1519                     if (dead_temps[arg]) {
1520                         dead_args |= (1 << i);
1521                     }
1522                     dead_temps[arg] = 0;
1523                 }
1524                 s->op_dead_args[oi] = dead_args;
1525                 s->op_sync_args[oi] = sync_args;
1526             }
1527             break;
1528         }
1529     }
1530 }
1531 #else
1532 /* dummy liveness analysis */
1533 static void tcg_liveness_analysis(TCGContext *s)
1534 {
1535     int nb_ops;
1536     nb_ops = s->gen_opc_ptr - s->gen_opc_buf;
1537 
1538     s->op_dead_args = tcg_malloc(nb_ops * sizeof(uint16_t));
1539     memset(s->op_dead_args, 0, nb_ops * sizeof(uint16_t));
1540     s->op_sync_args = tcg_malloc(nb_ops * sizeof(uint8_t));
1541     memset(s->op_sync_args, 0, nb_ops * sizeof(uint8_t));
1542 }
1543 #endif
1544 
1545 #ifndef NDEBUG
1546 static void dump_regs(TCGContext *s)
1547 {
1548     TCGTemp *ts;
1549     int i;
1550     char buf[64];
1551 
1552     for(i = 0; i < s->nb_temps; i++) {
1553         ts = &s->temps[i];
1554         printf("  %10s: ", tcg_get_arg_str_idx(s, buf, sizeof(buf), i));
1555         switch(ts->val_type) {
1556         case TEMP_VAL_REG:
1557             printf("%s", tcg_target_reg_names[ts->reg]);
1558             break;
1559         case TEMP_VAL_MEM:
1560             printf("%d(%s)", (int)ts->mem_offset, tcg_target_reg_names[ts->mem_reg]);
1561             break;
1562         case TEMP_VAL_CONST:
1563             printf("$0x%" TCG_PRIlx, ts->val);
1564             break;
1565         case TEMP_VAL_DEAD:
1566             printf("D");
1567             break;
1568         default:
1569             printf("???");
1570             break;
1571         }
1572         printf("\n");
1573     }
1574 
1575     for(i = 0; i < TCG_TARGET_NB_REGS; i++) {
1576         if (s->reg_to_temp[i] >= 0) {
1577             printf("%s: %s\n",
1578                    tcg_target_reg_names[i],
1579                    tcg_get_arg_str_idx(s, buf, sizeof(buf), s->reg_to_temp[i]));
1580         }
1581     }
1582 }
1583 
1584 static void check_regs(TCGContext *s)
1585 {
1586     int reg, k;
1587     TCGTemp *ts;
1588     char buf[64];
1589 
1590     for(reg = 0; reg < TCG_TARGET_NB_REGS; reg++) {
1591         k = s->reg_to_temp[reg];
1592         if (k >= 0) {
1593             ts = &s->temps[k];
1594             if (ts->val_type != TEMP_VAL_REG ||
1595                 ts->reg != reg) {
1596                 printf("Inconsistency for register %s:\n",
1597                        tcg_target_reg_names[reg]);
1598                 goto fail;
1599             }
1600         }
1601     }
1602     for(k = 0; k < s->nb_temps; k++) {
1603         ts = &s->temps[k];
1604         if (ts->val_type == TEMP_VAL_REG &&
1605             !ts->fixed_reg &&
1606             s->reg_to_temp[ts->reg] != k) {
1607                 printf("Inconsistency for temp %s:\n",
1608                        tcg_get_arg_str_idx(s, buf, sizeof(buf), k));
1609         fail:
1610                 printf("reg state:\n");
1611                 dump_regs(s);
1612                 tcg_abort();
1613         }
1614     }
1615 }
1616 #endif
1617 
1618 static void temp_allocate_frame(TCGContext *s, int temp)
1619 {
1620     TCGTemp *ts;
1621     ts = &s->temps[temp];
1622 #if !(defined(__sparc__) && TCG_TARGET_REG_BITS == 64)
1623     /* Sparc64 stack is accessed with offset of 2047 */
1624     s->current_frame_offset = (s->current_frame_offset +
1625                                (tcg_target_long)sizeof(tcg_target_long) - 1) &
1626         ~(sizeof(tcg_target_long) - 1);
1627 #endif
1628     if (s->current_frame_offset + (tcg_target_long)sizeof(tcg_target_long) >
1629         s->frame_end) {
1630         tcg_abort();
1631     }
1632     ts->mem_offset = s->current_frame_offset;
1633     ts->mem_reg = s->frame_reg;
1634     ts->mem_allocated = 1;
1635     s->current_frame_offset += sizeof(tcg_target_long);
1636 }
1637 
1638 /* sync register 'reg' by saving it to the corresponding temporary */
1639 static inline void tcg_reg_sync(TCGContext *s, int reg)
1640 {
1641     TCGTemp *ts;
1642     int temp;
1643 
1644     temp = s->reg_to_temp[reg];
1645     ts = &s->temps[temp];
1646     assert(ts->val_type == TEMP_VAL_REG);
1647     if (!ts->mem_coherent && !ts->fixed_reg) {
1648         if (!ts->mem_allocated) {
1649             temp_allocate_frame(s, temp);
1650         }
1651         tcg_out_st(s, ts->type, reg, ts->mem_reg, ts->mem_offset);
1652     }
1653     ts->mem_coherent = 1;
1654 }
1655 
1656 /* free register 'reg' by spilling the corresponding temporary if necessary */
1657 static void tcg_reg_free(TCGContext *s, int reg)
1658 {
1659     int temp;
1660 
1661     temp = s->reg_to_temp[reg];
1662     if (temp != -1) {
1663         tcg_reg_sync(s, reg);
1664         s->temps[temp].val_type = TEMP_VAL_MEM;
1665         s->reg_to_temp[reg] = -1;
1666     }
1667 }
1668 
1669 /* Allocate a register belonging to reg1 & ~reg2 */
1670 static int tcg_reg_alloc(TCGContext *s, TCGRegSet reg1, TCGRegSet reg2)
1671 {
1672     int i, reg;
1673     TCGRegSet reg_ct;
1674 
1675     tcg_regset_andnot(reg_ct, reg1, reg2);
1676 
1677     /* first try free registers */
1678     for(i = 0; i < ARRAY_SIZE(tcg_target_reg_alloc_order); i++) {
1679         reg = tcg_target_reg_alloc_order[i];
1680         if (tcg_regset_test_reg(reg_ct, reg) && s->reg_to_temp[reg] == -1)
1681             return reg;
1682     }
1683 
1684     /* XXX: do better spill choice */
1685     for(i = 0; i < ARRAY_SIZE(tcg_target_reg_alloc_order); i++) {
1686         reg = tcg_target_reg_alloc_order[i];
1687         if (tcg_regset_test_reg(reg_ct, reg)) {
1688             tcg_reg_free(s, reg);
1689             return reg;
1690         }
1691     }
1692 
1693     tcg_abort();
1694 }
1695 
1696 /* mark a temporary as dead. */
1697 static inline void temp_dead(TCGContext *s, int temp)
1698 {
1699     TCGTemp *ts;
1700 
1701     ts = &s->temps[temp];
1702     if (!ts->fixed_reg) {
1703         if (ts->val_type == TEMP_VAL_REG) {
1704             s->reg_to_temp[ts->reg] = -1;
1705         }
1706         if (temp < s->nb_globals || ts->temp_local) {
1707             ts->val_type = TEMP_VAL_MEM;
1708         } else {
1709             ts->val_type = TEMP_VAL_DEAD;
1710         }
1711     }
1712 }
1713 
1714 /* sync a temporary to memory. 'allocated_regs' is used in case a
1715    temporary registers needs to be allocated to store a constant. */
1716 static inline void temp_sync(TCGContext *s, int temp, TCGRegSet allocated_regs)
1717 {
1718     TCGTemp *ts;
1719 
1720     ts = &s->temps[temp];
1721     if (!ts->fixed_reg) {
1722         switch(ts->val_type) {
1723         case TEMP_VAL_CONST:
1724             ts->reg = tcg_reg_alloc(s, tcg_target_available_regs[ts->type],
1725                                     allocated_regs);
1726             ts->val_type = TEMP_VAL_REG;
1727             s->reg_to_temp[ts->reg] = temp;
1728             ts->mem_coherent = 0;
1729             tcg_out_movi(s, ts->type, ts->reg, ts->val);
1730             /* fallthrough*/
1731         case TEMP_VAL_REG:
1732             tcg_reg_sync(s, ts->reg);
1733             break;
1734         case TEMP_VAL_DEAD:
1735         case TEMP_VAL_MEM:
1736             break;
1737         default:
1738             tcg_abort();
1739         }
1740     }
1741 }
1742 
1743 /* save a temporary to memory. 'allocated_regs' is used in case a
1744    temporary registers needs to be allocated to store a constant. */
1745 static inline void temp_save(TCGContext *s, int temp, TCGRegSet allocated_regs)
1746 {
1747 #ifdef USE_LIVENESS_ANALYSIS
1748     /* The liveness analysis already ensures that globals are back
1749        in memory. Keep an assert for safety. */
1750     assert(s->temps[temp].val_type == TEMP_VAL_MEM || s->temps[temp].fixed_reg);
1751 #else
1752     temp_sync(s, temp, allocated_regs);
1753     temp_dead(s, temp);
1754 #endif
1755 }
1756 
1757 /* save globals to their canonical location and assume they can be
1758    modified be the following code. 'allocated_regs' is used in case a
1759    temporary registers needs to be allocated to store a constant. */
1760 static void save_globals(TCGContext *s, TCGRegSet allocated_regs)
1761 {
1762     int i;
1763 
1764     for(i = 0; i < s->nb_globals; i++) {
1765         temp_save(s, i, allocated_regs);
1766     }
1767 }
1768 
1769 /* sync globals to their canonical location and assume they can be
1770    read by the following code. 'allocated_regs' is used in case a
1771    temporary registers needs to be allocated to store a constant. */
1772 static void sync_globals(TCGContext *s, TCGRegSet allocated_regs)
1773 {
1774     int i;
1775 
1776     for (i = 0; i < s->nb_globals; i++) {
1777 #ifdef USE_LIVENESS_ANALYSIS
1778         assert(s->temps[i].val_type != TEMP_VAL_REG || s->temps[i].fixed_reg ||
1779                s->temps[i].mem_coherent);
1780 #else
1781         temp_sync(s, i, allocated_regs);
1782 #endif
1783     }
1784 }
1785 
1786 /* at the end of a basic block, we assume all temporaries are dead and
1787    all globals are stored at their canonical location. */
1788 static void tcg_reg_alloc_bb_end(TCGContext *s, TCGRegSet allocated_regs)
1789 {
1790     TCGTemp *ts;
1791     int i;
1792 
1793     for(i = s->nb_globals; i < s->nb_temps; i++) {
1794         ts = &s->temps[i];
1795         if (ts->temp_local) {
1796             temp_save(s, i, allocated_regs);
1797         } else {
1798 #ifdef USE_LIVENESS_ANALYSIS
1799             /* The liveness analysis already ensures that temps are dead.
1800                Keep an assert for safety. */
1801             assert(ts->val_type == TEMP_VAL_DEAD);
1802 #else
1803             temp_dead(s, i);
1804 #endif
1805         }
1806     }
1807 
1808     save_globals(s, allocated_regs);
1809 }
1810 
1811 #define IS_DEAD_ARG(n) ((dead_args >> (n)) & 1)
1812 #define NEED_SYNC_ARG(n) ((sync_args >> (n)) & 1)
1813 
1814 static void tcg_reg_alloc_movi(TCGContext *s, const TCGArg *args,
1815                                uint16_t dead_args, uint8_t sync_args)
1816 {
1817     TCGTemp *ots;
1818     tcg_target_ulong val;
1819 
1820     ots = &s->temps[args[0]];
1821     val = args[1];
1822 
1823     if (ots->fixed_reg) {
1824         /* for fixed registers, we do not do any constant
1825            propagation */
1826         tcg_out_movi(s, ots->type, ots->reg, val);
1827     } else {
1828         /* The movi is not explicitly generated here */
1829         if (ots->val_type == TEMP_VAL_REG)
1830             s->reg_to_temp[ots->reg] = -1;
1831         ots->val_type = TEMP_VAL_CONST;
1832         ots->val = val;
1833     }
1834     if (NEED_SYNC_ARG(0)) {
1835         temp_sync(s, args[0], s->reserved_regs);
1836     }
1837     if (IS_DEAD_ARG(0)) {
1838         temp_dead(s, args[0]);
1839     }
1840 }
1841 
1842 static void tcg_reg_alloc_mov(TCGContext *s, const TCGOpDef *def,
1843                               const TCGArg *args, uint16_t dead_args,
1844                               uint8_t sync_args)
1845 {
1846     TCGRegSet allocated_regs;
1847     TCGTemp *ts, *ots;
1848     TCGType otype, itype;
1849 
1850     tcg_regset_set(allocated_regs, s->reserved_regs);
1851     ots = &s->temps[args[0]];
1852     ts = &s->temps[args[1]];
1853 
1854     /* Note that otype != itype for no-op truncation.  */
1855     otype = ots->type;
1856     itype = ts->type;
1857 
1858     /* If the source value is not in a register, and we're going to be
1859        forced to have it in a register in order to perform the copy,
1860        then copy the SOURCE value into its own register first.  That way
1861        we don't have to reload SOURCE the next time it is used. */
1862     if (((NEED_SYNC_ARG(0) || ots->fixed_reg) && ts->val_type != TEMP_VAL_REG)
1863         || ts->val_type == TEMP_VAL_MEM) {
1864         ts->reg = tcg_reg_alloc(s, tcg_target_available_regs[itype],
1865                                 allocated_regs);
1866         if (ts->val_type == TEMP_VAL_MEM) {
1867             tcg_out_ld(s, itype, ts->reg, ts->mem_reg, ts->mem_offset);
1868             ts->mem_coherent = 1;
1869         } else if (ts->val_type == TEMP_VAL_CONST) {
1870             tcg_out_movi(s, itype, ts->reg, ts->val);
1871         }
1872         s->reg_to_temp[ts->reg] = args[1];
1873         ts->val_type = TEMP_VAL_REG;
1874     }
1875 
1876     if (IS_DEAD_ARG(0) && !ots->fixed_reg) {
1877         /* mov to a non-saved dead register makes no sense (even with
1878            liveness analysis disabled). */
1879         assert(NEED_SYNC_ARG(0));
1880         /* The code above should have moved the temp to a register. */
1881         assert(ts->val_type == TEMP_VAL_REG);
1882         if (!ots->mem_allocated) {
1883             temp_allocate_frame(s, args[0]);
1884         }
1885         tcg_out_st(s, otype, ts->reg, ots->mem_reg, ots->mem_offset);
1886         if (IS_DEAD_ARG(1)) {
1887             temp_dead(s, args[1]);
1888         }
1889         temp_dead(s, args[0]);
1890     } else if (ts->val_type == TEMP_VAL_CONST) {
1891         /* propagate constant */
1892         if (ots->val_type == TEMP_VAL_REG) {
1893             s->reg_to_temp[ots->reg] = -1;
1894         }
1895         ots->val_type = TEMP_VAL_CONST;
1896         ots->val = ts->val;
1897     } else {
1898         /* The code in the first if block should have moved the
1899            temp to a register. */
1900         assert(ts->val_type == TEMP_VAL_REG);
1901         if (IS_DEAD_ARG(1) && !ts->fixed_reg && !ots->fixed_reg) {
1902             /* the mov can be suppressed */
1903             if (ots->val_type == TEMP_VAL_REG) {
1904                 s->reg_to_temp[ots->reg] = -1;
1905             }
1906             ots->reg = ts->reg;
1907             temp_dead(s, args[1]);
1908         } else {
1909             if (ots->val_type != TEMP_VAL_REG) {
1910                 /* When allocating a new register, make sure to not spill the
1911                    input one. */
1912                 tcg_regset_set_reg(allocated_regs, ts->reg);
1913                 ots->reg = tcg_reg_alloc(s, tcg_target_available_regs[otype],
1914                                          allocated_regs);
1915             }
1916             tcg_out_mov(s, otype, ots->reg, ts->reg);
1917         }
1918         ots->val_type = TEMP_VAL_REG;
1919         ots->mem_coherent = 0;
1920         s->reg_to_temp[ots->reg] = args[0];
1921         if (NEED_SYNC_ARG(0)) {
1922             tcg_reg_sync(s, ots->reg);
1923         }
1924     }
1925 }
1926 
1927 static void tcg_reg_alloc_op(TCGContext *s,
1928                              const TCGOpDef *def, TCGOpcode opc,
1929                              const TCGArg *args, uint16_t dead_args,
1930                              uint8_t sync_args)
1931 {
1932     TCGRegSet allocated_regs;
1933     int i, k, nb_iargs, nb_oargs, reg;
1934     TCGArg arg;
1935     const TCGArgConstraint *arg_ct;
1936     TCGTemp *ts;
1937     TCGArg new_args[TCG_MAX_OP_ARGS];
1938     int const_args[TCG_MAX_OP_ARGS];
1939 
1940     nb_oargs = def->nb_oargs;
1941     nb_iargs = def->nb_iargs;
1942 
1943     /* copy constants */
1944     memcpy(new_args + nb_oargs + nb_iargs,
1945            args + nb_oargs + nb_iargs,
1946            sizeof(TCGArg) * def->nb_cargs);
1947 
1948     /* satisfy input constraints */
1949     tcg_regset_set(allocated_regs, s->reserved_regs);
1950     for(k = 0; k < nb_iargs; k++) {
1951         i = def->sorted_args[nb_oargs + k];
1952         arg = args[i];
1953         arg_ct = &def->args_ct[i];
1954         ts = &s->temps[arg];
1955         if (ts->val_type == TEMP_VAL_MEM) {
1956             reg = tcg_reg_alloc(s, arg_ct->u.regs, allocated_regs);
1957             tcg_out_ld(s, ts->type, reg, ts->mem_reg, ts->mem_offset);
1958             ts->val_type = TEMP_VAL_REG;
1959             ts->reg = reg;
1960             ts->mem_coherent = 1;
1961             s->reg_to_temp[reg] = arg;
1962         } else if (ts->val_type == TEMP_VAL_CONST) {
1963             if (tcg_target_const_match(ts->val, ts->type, arg_ct)) {
1964                 /* constant is OK for instruction */
1965                 const_args[i] = 1;
1966                 new_args[i] = ts->val;
1967                 goto iarg_end;
1968             } else {
1969                 /* need to move to a register */
1970                 reg = tcg_reg_alloc(s, arg_ct->u.regs, allocated_regs);
1971                 tcg_out_movi(s, ts->type, reg, ts->val);
1972                 ts->val_type = TEMP_VAL_REG;
1973                 ts->reg = reg;
1974                 ts->mem_coherent = 0;
1975                 s->reg_to_temp[reg] = arg;
1976             }
1977         }
1978         assert(ts->val_type == TEMP_VAL_REG);
1979         if (arg_ct->ct & TCG_CT_IALIAS) {
1980             if (ts->fixed_reg) {
1981                 /* if fixed register, we must allocate a new register
1982                    if the alias is not the same register */
1983                 if (arg != args[arg_ct->alias_index])
1984                     goto allocate_in_reg;
1985             } else {
1986                 /* if the input is aliased to an output and if it is
1987                    not dead after the instruction, we must allocate
1988                    a new register and move it */
1989                 if (!IS_DEAD_ARG(i)) {
1990                     goto allocate_in_reg;
1991                 }
1992             }
1993         }
1994         reg = ts->reg;
1995         if (tcg_regset_test_reg(arg_ct->u.regs, reg)) {
1996             /* nothing to do : the constraint is satisfied */
1997         } else {
1998         allocate_in_reg:
1999             /* allocate a new register matching the constraint
2000                and move the temporary register into it */
2001             reg = tcg_reg_alloc(s, arg_ct->u.regs, allocated_regs);
2002             tcg_out_mov(s, ts->type, reg, ts->reg);
2003         }
2004         new_args[i] = reg;
2005         const_args[i] = 0;
2006         tcg_regset_set_reg(allocated_regs, reg);
2007     iarg_end: ;
2008     }
2009 
2010     /* mark dead temporaries and free the associated registers */
2011     for (i = nb_oargs; i < nb_oargs + nb_iargs; i++) {
2012         if (IS_DEAD_ARG(i)) {
2013             temp_dead(s, args[i]);
2014         }
2015     }
2016 
2017     if (def->flags & TCG_OPF_BB_END) {
2018         tcg_reg_alloc_bb_end(s, allocated_regs);
2019     } else {
2020         if (def->flags & TCG_OPF_CALL_CLOBBER) {
2021             /* XXX: permit generic clobber register list ? */
2022             for(reg = 0; reg < TCG_TARGET_NB_REGS; reg++) {
2023                 if (tcg_regset_test_reg(tcg_target_call_clobber_regs, reg)) {
2024                     tcg_reg_free(s, reg);
2025                 }
2026             }
2027         }
2028         if (def->flags & TCG_OPF_SIDE_EFFECTS) {
2029             /* sync globals if the op has side effects and might trigger
2030                an exception. */
2031             sync_globals(s, allocated_regs);
2032         }
2033 
2034         /* satisfy the output constraints */
2035         tcg_regset_set(allocated_regs, s->reserved_regs);
2036         for(k = 0; k < nb_oargs; k++) {
2037             i = def->sorted_args[k];
2038             arg = args[i];
2039             arg_ct = &def->args_ct[i];
2040             ts = &s->temps[arg];
2041             if (arg_ct->ct & TCG_CT_ALIAS) {
2042                 reg = new_args[arg_ct->alias_index];
2043             } else {
2044                 /* if fixed register, we try to use it */
2045                 reg = ts->reg;
2046                 if (ts->fixed_reg &&
2047                     tcg_regset_test_reg(arg_ct->u.regs, reg)) {
2048                     goto oarg_end;
2049                 }
2050                 reg = tcg_reg_alloc(s, arg_ct->u.regs, allocated_regs);
2051             }
2052             tcg_regset_set_reg(allocated_regs, reg);
2053             /* if a fixed register is used, then a move will be done afterwards */
2054             if (!ts->fixed_reg) {
2055                 if (ts->val_type == TEMP_VAL_REG) {
2056                     s->reg_to_temp[ts->reg] = -1;
2057                 }
2058                 ts->val_type = TEMP_VAL_REG;
2059                 ts->reg = reg;
2060                 /* temp value is modified, so the value kept in memory is
2061                    potentially not the same */
2062                 ts->mem_coherent = 0;
2063                 s->reg_to_temp[reg] = arg;
2064             }
2065         oarg_end:
2066             new_args[i] = reg;
2067         }
2068     }
2069 
2070     /* emit instruction */
2071     tcg_out_op(s, opc, new_args, const_args);
2072 
2073     /* move the outputs in the correct register if needed */
2074     for(i = 0; i < nb_oargs; i++) {
2075         ts = &s->temps[args[i]];
2076         reg = new_args[i];
2077         if (ts->fixed_reg && ts->reg != reg) {
2078             tcg_out_mov(s, ts->type, ts->reg, reg);
2079         }
2080         if (NEED_SYNC_ARG(i)) {
2081             tcg_reg_sync(s, reg);
2082         }
2083         if (IS_DEAD_ARG(i)) {
2084             temp_dead(s, args[i]);
2085         }
2086     }
2087 }
2088 
2089 #ifdef TCG_TARGET_STACK_GROWSUP
2090 #define STACK_DIR(x) (-(x))
2091 #else
2092 #define STACK_DIR(x) (x)
2093 #endif
2094 
2095 static void tcg_reg_alloc_call(TCGContext *s, int nb_oargs, int nb_iargs,
2096                                const TCGArg * const args, uint16_t dead_args,
2097                                uint8_t sync_args)
2098 {
2099     int flags, nb_regs, i, reg;
2100     TCGArg arg;
2101     TCGTemp *ts;
2102     intptr_t stack_offset;
2103     size_t call_stack_size;
2104     tcg_insn_unit *func_addr;
2105     int allocate_args;
2106     TCGRegSet allocated_regs;
2107 
2108     func_addr = (tcg_insn_unit *)(intptr_t)args[nb_oargs + nb_iargs];
2109     flags = args[nb_oargs + nb_iargs + 1];
2110 
2111     nb_regs = ARRAY_SIZE(tcg_target_call_iarg_regs);
2112     if (nb_regs > nb_iargs) {
2113         nb_regs = nb_iargs;
2114     }
2115 
2116     /* assign stack slots first */
2117     call_stack_size = (nb_iargs - nb_regs) * sizeof(tcg_target_long);
2118     call_stack_size = (call_stack_size + TCG_TARGET_STACK_ALIGN - 1) &
2119         ~(TCG_TARGET_STACK_ALIGN - 1);
2120     allocate_args = (call_stack_size > TCG_STATIC_CALL_ARGS_SIZE);
2121     if (allocate_args) {
2122         /* XXX: if more than TCG_STATIC_CALL_ARGS_SIZE is needed,
2123            preallocate call stack */
2124         tcg_abort();
2125     }
2126 
2127     stack_offset = TCG_TARGET_CALL_STACK_OFFSET;
2128     for(i = nb_regs; i < nb_iargs; i++) {
2129         arg = args[nb_oargs + i];
2130 #ifdef TCG_TARGET_STACK_GROWSUP
2131         stack_offset -= sizeof(tcg_target_long);
2132 #endif
2133         if (arg != TCG_CALL_DUMMY_ARG) {
2134             ts = &s->temps[arg];
2135             if (ts->val_type == TEMP_VAL_REG) {
2136                 tcg_out_st(s, ts->type, ts->reg, TCG_REG_CALL_STACK, stack_offset);
2137             } else if (ts->val_type == TEMP_VAL_MEM) {
2138                 reg = tcg_reg_alloc(s, tcg_target_available_regs[ts->type],
2139                                     s->reserved_regs);
2140                 /* XXX: not correct if reading values from the stack */
2141                 tcg_out_ld(s, ts->type, reg, ts->mem_reg, ts->mem_offset);
2142                 tcg_out_st(s, ts->type, reg, TCG_REG_CALL_STACK, stack_offset);
2143             } else if (ts->val_type == TEMP_VAL_CONST) {
2144                 reg = tcg_reg_alloc(s, tcg_target_available_regs[ts->type],
2145                                     s->reserved_regs);
2146                 /* XXX: sign extend may be needed on some targets */
2147                 tcg_out_movi(s, ts->type, reg, ts->val);
2148                 tcg_out_st(s, ts->type, reg, TCG_REG_CALL_STACK, stack_offset);
2149             } else {
2150                 tcg_abort();
2151             }
2152         }
2153 #ifndef TCG_TARGET_STACK_GROWSUP
2154         stack_offset += sizeof(tcg_target_long);
2155 #endif
2156     }
2157 
2158     /* assign input registers */
2159     tcg_regset_set(allocated_regs, s->reserved_regs);
2160     for(i = 0; i < nb_regs; i++) {
2161         arg = args[nb_oargs + i];
2162         if (arg != TCG_CALL_DUMMY_ARG) {
2163             ts = &s->temps[arg];
2164             reg = tcg_target_call_iarg_regs[i];
2165             tcg_reg_free(s, reg);
2166             if (ts->val_type == TEMP_VAL_REG) {
2167                 if (ts->reg != reg) {
2168                     tcg_out_mov(s, ts->type, reg, ts->reg);
2169                 }
2170             } else if (ts->val_type == TEMP_VAL_MEM) {
2171                 tcg_out_ld(s, ts->type, reg, ts->mem_reg, ts->mem_offset);
2172             } else if (ts->val_type == TEMP_VAL_CONST) {
2173                 /* XXX: sign extend ? */
2174                 tcg_out_movi(s, ts->type, reg, ts->val);
2175             } else {
2176                 tcg_abort();
2177             }
2178             tcg_regset_set_reg(allocated_regs, reg);
2179         }
2180     }
2181 
2182     /* mark dead temporaries and free the associated registers */
2183     for(i = nb_oargs; i < nb_iargs + nb_oargs; i++) {
2184         if (IS_DEAD_ARG(i)) {
2185             temp_dead(s, args[i]);
2186         }
2187     }
2188 
2189     /* clobber call registers */
2190     for(reg = 0; reg < TCG_TARGET_NB_REGS; reg++) {
2191         if (tcg_regset_test_reg(tcg_target_call_clobber_regs, reg)) {
2192             tcg_reg_free(s, reg);
2193         }
2194     }
2195 
2196     /* Save globals if they might be written by the helper, sync them if
2197        they might be read. */
2198     if (flags & TCG_CALL_NO_READ_GLOBALS) {
2199         /* Nothing to do */
2200     } else if (flags & TCG_CALL_NO_WRITE_GLOBALS) {
2201         sync_globals(s, allocated_regs);
2202     } else {
2203         save_globals(s, allocated_regs);
2204     }
2205 
2206     tcg_out_call(s, func_addr);
2207 
2208     /* assign output registers and emit moves if needed */
2209     for(i = 0; i < nb_oargs; i++) {
2210         arg = args[i];
2211         ts = &s->temps[arg];
2212         reg = tcg_target_call_oarg_regs[i];
2213         assert(s->reg_to_temp[reg] == -1);
2214 
2215         if (ts->fixed_reg) {
2216             if (ts->reg != reg) {
2217                 tcg_out_mov(s, ts->type, ts->reg, reg);
2218             }
2219         } else {
2220             if (ts->val_type == TEMP_VAL_REG) {
2221                 s->reg_to_temp[ts->reg] = -1;
2222             }
2223             ts->val_type = TEMP_VAL_REG;
2224             ts->reg = reg;
2225             ts->mem_coherent = 0;
2226             s->reg_to_temp[reg] = arg;
2227             if (NEED_SYNC_ARG(i)) {
2228                 tcg_reg_sync(s, reg);
2229             }
2230             if (IS_DEAD_ARG(i)) {
2231                 temp_dead(s, args[i]);
2232             }
2233         }
2234     }
2235 }
2236 
2237 #ifdef CONFIG_PROFILER
2238 
2239 static int64_t tcg_table_op_count[NB_OPS];
2240 
2241 void tcg_dump_op_count(FILE *f, fprintf_function cpu_fprintf)
2242 {
2243     int i;
2244 
2245     for (i = 0; i < NB_OPS; i++) {
2246         cpu_fprintf(f, "%s %" PRId64 "\n", tcg_op_defs[i].name,
2247                     tcg_table_op_count[i]);
2248     }
2249 }
2250 #else
2251 void tcg_dump_op_count(FILE *f, fprintf_function cpu_fprintf)
2252 {
2253     cpu_fprintf(f, "[TCG profiler not compiled]\n");
2254 }
2255 #endif
2256 
2257 
2258 static inline int tcg_gen_code_common(TCGContext *s,
2259                                       tcg_insn_unit *gen_code_buf,
2260                                       long search_pc)
2261 {
2262     int oi, oi_next;
2263 
2264 #ifdef DEBUG_DISAS
2265     if (unlikely(qemu_loglevel_mask(CPU_LOG_TB_OP))) {
2266         qemu_log("OP:\n");
2267         tcg_dump_ops(s);
2268         qemu_log("\n");
2269     }
2270 #endif
2271 
2272 #ifdef CONFIG_PROFILER
2273     s->opt_time -= profile_getclock();
2274 #endif
2275 
2276 #ifdef USE_TCG_OPTIMIZATIONS
2277     tcg_optimize(s);
2278 #endif
2279 
2280 #ifdef CONFIG_PROFILER
2281     s->opt_time += profile_getclock();
2282     s->la_time -= profile_getclock();
2283 #endif
2284 
2285     tcg_liveness_analysis(s);
2286 
2287 #ifdef CONFIG_PROFILER
2288     s->la_time += profile_getclock();
2289 #endif
2290 
2291 #ifdef DEBUG_DISAS
2292     if (unlikely(qemu_loglevel_mask(CPU_LOG_TB_OP_OPT))) {
2293         qemu_log("OP after optimization and liveness analysis:\n");
2294         tcg_dump_ops(s);
2295         qemu_log("\n");
2296     }
2297 #endif
2298 
2299     tcg_reg_alloc_start(s);
2300 
2301     s->code_buf = gen_code_buf;
2302     s->code_ptr = gen_code_buf;
2303 
2304     tcg_out_tb_init(s);
2305 
2306     for (oi = s->gen_first_op_idx; oi >= 0; oi = oi_next) {
2307         TCGOp * const op = &s->gen_op_buf[oi];
2308         TCGArg * const args = &s->gen_opparam_buf[op->args];
2309         TCGOpcode opc = op->opc;
2310         const TCGOpDef *def = &tcg_op_defs[opc];
2311         uint16_t dead_args = s->op_dead_args[oi];
2312         uint8_t sync_args = s->op_sync_args[oi];
2313 
2314         oi_next = op->next;
2315 #ifdef CONFIG_PROFILER
2316         tcg_table_op_count[opc]++;
2317 #endif
2318 
2319         switch (opc) {
2320         case INDEX_op_mov_i32:
2321         case INDEX_op_mov_i64:
2322             tcg_reg_alloc_mov(s, def, args, dead_args, sync_args);
2323             break;
2324         case INDEX_op_movi_i32:
2325         case INDEX_op_movi_i64:
2326             tcg_reg_alloc_movi(s, args, dead_args, sync_args);
2327             break;
2328         case INDEX_op_debug_insn_start:
2329             break;
2330         case INDEX_op_discard:
2331             temp_dead(s, args[0]);
2332             break;
2333         case INDEX_op_set_label:
2334             tcg_reg_alloc_bb_end(s, s->reserved_regs);
2335             tcg_out_label(s, args[0], s->code_ptr);
2336             break;
2337         case INDEX_op_call:
2338             tcg_reg_alloc_call(s, op->callo, op->calli, args,
2339                                dead_args, sync_args);
2340             break;
2341         default:
2342             /* Sanity check that we've not introduced any unhandled opcodes. */
2343             if (def->flags & TCG_OPF_NOT_PRESENT) {
2344                 tcg_abort();
2345             }
2346             /* Note: in order to speed up the code, it would be much
2347                faster to have specialized register allocator functions for
2348                some common argument patterns */
2349             tcg_reg_alloc_op(s, def, opc, args, dead_args, sync_args);
2350             break;
2351         }
2352         if (search_pc >= 0 && search_pc < tcg_current_code_size(s)) {
2353             return oi;
2354         }
2355 #ifndef NDEBUG
2356         check_regs(s);
2357 #endif
2358     }
2359 
2360     /* Generate TB finalization at the end of block */
2361     tcg_out_tb_finalize(s);
2362     return -1;
2363 }
2364 
2365 int tcg_gen_code(TCGContext *s, tcg_insn_unit *gen_code_buf)
2366 {
2367 #ifdef CONFIG_PROFILER
2368     {
2369         int n;
2370 
2371         n = s->gen_last_op_idx + 1;
2372         s->op_count += n;
2373         if (n > s->op_count_max) {
2374             s->op_count_max = n;
2375         }
2376 
2377         n = s->nb_temps;
2378         s->temp_count += n;
2379         if (n > s->temp_count_max) {
2380             s->temp_count_max = n;
2381         }
2382     }
2383 #endif
2384 
2385     tcg_gen_code_common(s, gen_code_buf, -1);
2386 
2387     /* flush instruction cache */
2388     flush_icache_range((uintptr_t)s->code_buf, (uintptr_t)s->code_ptr);
2389 
2390     return tcg_current_code_size(s);
2391 }
2392 
2393 /* Return the index of the micro operation such as the pc after is <
2394    offset bytes from the start of the TB.  The contents of gen_code_buf must
2395    not be changed, though writing the same values is ok.
2396    Return -1 if not found. */
2397 int tcg_gen_code_search_pc(TCGContext *s, tcg_insn_unit *gen_code_buf,
2398                            long offset)
2399 {
2400     return tcg_gen_code_common(s, gen_code_buf, offset);
2401 }
2402 
2403 #ifdef CONFIG_PROFILER
2404 void tcg_dump_info(FILE *f, fprintf_function cpu_fprintf)
2405 {
2406     TCGContext *s = &tcg_ctx;
2407     int64_t tot;
2408 
2409     tot = s->interm_time + s->code_time;
2410     cpu_fprintf(f, "JIT cycles          %" PRId64 " (%0.3f s at 2.4 GHz)\n",
2411                 tot, tot / 2.4e9);
2412     cpu_fprintf(f, "translated TBs      %" PRId64 " (aborted=%" PRId64 " %0.1f%%)\n",
2413                 s->tb_count,
2414                 s->tb_count1 - s->tb_count,
2415                 s->tb_count1 ? (double)(s->tb_count1 - s->tb_count) / s->tb_count1 * 100.0 : 0);
2416     cpu_fprintf(f, "avg ops/TB          %0.1f max=%d\n",
2417                 s->tb_count ? (double)s->op_count / s->tb_count : 0, s->op_count_max);
2418     cpu_fprintf(f, "deleted ops/TB      %0.2f\n",
2419                 s->tb_count ?
2420                 (double)s->del_op_count / s->tb_count : 0);
2421     cpu_fprintf(f, "avg temps/TB        %0.2f max=%d\n",
2422                 s->tb_count ?
2423                 (double)s->temp_count / s->tb_count : 0,
2424                 s->temp_count_max);
2425 
2426     cpu_fprintf(f, "cycles/op           %0.1f\n",
2427                 s->op_count ? (double)tot / s->op_count : 0);
2428     cpu_fprintf(f, "cycles/in byte      %0.1f\n",
2429                 s->code_in_len ? (double)tot / s->code_in_len : 0);
2430     cpu_fprintf(f, "cycles/out byte     %0.1f\n",
2431                 s->code_out_len ? (double)tot / s->code_out_len : 0);
2432     if (tot == 0)
2433         tot = 1;
2434     cpu_fprintf(f, "  gen_interm time   %0.1f%%\n",
2435                 (double)s->interm_time / tot * 100.0);
2436     cpu_fprintf(f, "  gen_code time     %0.1f%%\n",
2437                 (double)s->code_time / tot * 100.0);
2438     cpu_fprintf(f, "optim./code time    %0.1f%%\n",
2439                 (double)s->opt_time / (s->code_time ? s->code_time : 1)
2440                 * 100.0);
2441     cpu_fprintf(f, "liveness/code time  %0.1f%%\n",
2442                 (double)s->la_time / (s->code_time ? s->code_time : 1) * 100.0);
2443     cpu_fprintf(f, "cpu_restore count   %" PRId64 "\n",
2444                 s->restore_count);
2445     cpu_fprintf(f, "  avg cycles        %0.1f\n",
2446                 s->restore_count ? (double)s->restore_time / s->restore_count : 0);
2447 }
2448 #else
2449 void tcg_dump_info(FILE *f, fprintf_function cpu_fprintf)
2450 {
2451     cpu_fprintf(f, "[TCG profiler not compiled]\n");
2452 }
2453 #endif
2454 
2455 #ifdef ELF_HOST_MACHINE
2456 /* In order to use this feature, the backend needs to do three things:
2457 
2458    (1) Define ELF_HOST_MACHINE to indicate both what value to
2459        put into the ELF image and to indicate support for the feature.
2460 
2461    (2) Define tcg_register_jit.  This should create a buffer containing
2462        the contents of a .debug_frame section that describes the post-
2463        prologue unwind info for the tcg machine.
2464 
2465    (3) Call tcg_register_jit_int, with the constructed .debug_frame.
2466 */
2467 
2468 /* Begin GDB interface.  THE FOLLOWING MUST MATCH GDB DOCS.  */
2469 typedef enum {
2470     JIT_NOACTION = 0,
2471     JIT_REGISTER_FN,
2472     JIT_UNREGISTER_FN
2473 } jit_actions_t;
2474 
2475 struct jit_code_entry {
2476     struct jit_code_entry *next_entry;
2477     struct jit_code_entry *prev_entry;
2478     const void *symfile_addr;
2479     uint64_t symfile_size;
2480 };
2481 
2482 struct jit_descriptor {
2483     uint32_t version;
2484     uint32_t action_flag;
2485     struct jit_code_entry *relevant_entry;
2486     struct jit_code_entry *first_entry;
2487 };
2488 
2489 void __jit_debug_register_code(void) __attribute__((noinline));
2490 void __jit_debug_register_code(void)
2491 {
2492     asm("");
2493 }
2494 
2495 /* Must statically initialize the version, because GDB may check
2496    the version before we can set it.  */
2497 struct jit_descriptor __jit_debug_descriptor = { 1, 0, 0, 0 };
2498 
2499 /* End GDB interface.  */
2500 
2501 static int find_string(const char *strtab, const char *str)
2502 {
2503     const char *p = strtab + 1;
2504 
2505     while (1) {
2506         if (strcmp(p, str) == 0) {
2507             return p - strtab;
2508         }
2509         p += strlen(p) + 1;
2510     }
2511 }
2512 
2513 static void tcg_register_jit_int(void *buf_ptr, size_t buf_size,
2514                                  const void *debug_frame,
2515                                  size_t debug_frame_size)
2516 {
2517     struct __attribute__((packed)) DebugInfo {
2518         uint32_t  len;
2519         uint16_t  version;
2520         uint32_t  abbrev;
2521         uint8_t   ptr_size;
2522         uint8_t   cu_die;
2523         uint16_t  cu_lang;
2524         uintptr_t cu_low_pc;
2525         uintptr_t cu_high_pc;
2526         uint8_t   fn_die;
2527         char      fn_name[16];
2528         uintptr_t fn_low_pc;
2529         uintptr_t fn_high_pc;
2530         uint8_t   cu_eoc;
2531     };
2532 
2533     struct ElfImage {
2534         ElfW(Ehdr) ehdr;
2535         ElfW(Phdr) phdr;
2536         ElfW(Shdr) shdr[7];
2537         ElfW(Sym)  sym[2];
2538         struct DebugInfo di;
2539         uint8_t    da[24];
2540         char       str[80];
2541     };
2542 
2543     struct ElfImage *img;
2544 
2545     static const struct ElfImage img_template = {
2546         .ehdr = {
2547             .e_ident[EI_MAG0] = ELFMAG0,
2548             .e_ident[EI_MAG1] = ELFMAG1,
2549             .e_ident[EI_MAG2] = ELFMAG2,
2550             .e_ident[EI_MAG3] = ELFMAG3,
2551             .e_ident[EI_CLASS] = ELF_CLASS,
2552             .e_ident[EI_DATA] = ELF_DATA,
2553             .e_ident[EI_VERSION] = EV_CURRENT,
2554             .e_type = ET_EXEC,
2555             .e_machine = ELF_HOST_MACHINE,
2556             .e_version = EV_CURRENT,
2557             .e_phoff = offsetof(struct ElfImage, phdr),
2558             .e_shoff = offsetof(struct ElfImage, shdr),
2559             .e_ehsize = sizeof(ElfW(Shdr)),
2560             .e_phentsize = sizeof(ElfW(Phdr)),
2561             .e_phnum = 1,
2562             .e_shentsize = sizeof(ElfW(Shdr)),
2563             .e_shnum = ARRAY_SIZE(img->shdr),
2564             .e_shstrndx = ARRAY_SIZE(img->shdr) - 1,
2565 #ifdef ELF_HOST_FLAGS
2566             .e_flags = ELF_HOST_FLAGS,
2567 #endif
2568 #ifdef ELF_OSABI
2569             .e_ident[EI_OSABI] = ELF_OSABI,
2570 #endif
2571         },
2572         .phdr = {
2573             .p_type = PT_LOAD,
2574             .p_flags = PF_X,
2575         },
2576         .shdr = {
2577             [0] = { .sh_type = SHT_NULL },
2578             /* Trick: The contents of code_gen_buffer are not present in
2579                this fake ELF file; that got allocated elsewhere.  Therefore
2580                we mark .text as SHT_NOBITS (similar to .bss) so that readers
2581                will not look for contents.  We can record any address.  */
2582             [1] = { /* .text */
2583                 .sh_type = SHT_NOBITS,
2584                 .sh_flags = SHF_EXECINSTR | SHF_ALLOC,
2585             },
2586             [2] = { /* .debug_info */
2587                 .sh_type = SHT_PROGBITS,
2588                 .sh_offset = offsetof(struct ElfImage, di),
2589                 .sh_size = sizeof(struct DebugInfo),
2590             },
2591             [3] = { /* .debug_abbrev */
2592                 .sh_type = SHT_PROGBITS,
2593                 .sh_offset = offsetof(struct ElfImage, da),
2594                 .sh_size = sizeof(img->da),
2595             },
2596             [4] = { /* .debug_frame */
2597                 .sh_type = SHT_PROGBITS,
2598                 .sh_offset = sizeof(struct ElfImage),
2599             },
2600             [5] = { /* .symtab */
2601                 .sh_type = SHT_SYMTAB,
2602                 .sh_offset = offsetof(struct ElfImage, sym),
2603                 .sh_size = sizeof(img->sym),
2604                 .sh_info = 1,
2605                 .sh_link = ARRAY_SIZE(img->shdr) - 1,
2606                 .sh_entsize = sizeof(ElfW(Sym)),
2607             },
2608             [6] = { /* .strtab */
2609                 .sh_type = SHT_STRTAB,
2610                 .sh_offset = offsetof(struct ElfImage, str),
2611                 .sh_size = sizeof(img->str),
2612             }
2613         },
2614         .sym = {
2615             [1] = { /* code_gen_buffer */
2616                 .st_info = ELF_ST_INFO(STB_GLOBAL, STT_FUNC),
2617                 .st_shndx = 1,
2618             }
2619         },
2620         .di = {
2621             .len = sizeof(struct DebugInfo) - 4,
2622             .version = 2,
2623             .ptr_size = sizeof(void *),
2624             .cu_die = 1,
2625             .cu_lang = 0x8001,  /* DW_LANG_Mips_Assembler */
2626             .fn_die = 2,
2627             .fn_name = "code_gen_buffer"
2628         },
2629         .da = {
2630             1,          /* abbrev number (the cu) */
2631             0x11, 1,    /* DW_TAG_compile_unit, has children */
2632             0x13, 0x5,  /* DW_AT_language, DW_FORM_data2 */
2633             0x11, 0x1,  /* DW_AT_low_pc, DW_FORM_addr */
2634             0x12, 0x1,  /* DW_AT_high_pc, DW_FORM_addr */
2635             0, 0,       /* end of abbrev */
2636             2,          /* abbrev number (the fn) */
2637             0x2e, 0,    /* DW_TAG_subprogram, no children */
2638             0x3, 0x8,   /* DW_AT_name, DW_FORM_string */
2639             0x11, 0x1,  /* DW_AT_low_pc, DW_FORM_addr */
2640             0x12, 0x1,  /* DW_AT_high_pc, DW_FORM_addr */
2641             0, 0,       /* end of abbrev */
2642             0           /* no more abbrev */
2643         },
2644         .str = "\0" ".text\0" ".debug_info\0" ".debug_abbrev\0"
2645                ".debug_frame\0" ".symtab\0" ".strtab\0" "code_gen_buffer",
2646     };
2647 
2648     /* We only need a single jit entry; statically allocate it.  */
2649     static struct jit_code_entry one_entry;
2650 
2651     uintptr_t buf = (uintptr_t)buf_ptr;
2652     size_t img_size = sizeof(struct ElfImage) + debug_frame_size;
2653     DebugFrameHeader *dfh;
2654 
2655     img = g_malloc(img_size);
2656     *img = img_template;
2657 
2658     img->phdr.p_vaddr = buf;
2659     img->phdr.p_paddr = buf;
2660     img->phdr.p_memsz = buf_size;
2661 
2662     img->shdr[1].sh_name = find_string(img->str, ".text");
2663     img->shdr[1].sh_addr = buf;
2664     img->shdr[1].sh_size = buf_size;
2665 
2666     img->shdr[2].sh_name = find_string(img->str, ".debug_info");
2667     img->shdr[3].sh_name = find_string(img->str, ".debug_abbrev");
2668 
2669     img->shdr[4].sh_name = find_string(img->str, ".debug_frame");
2670     img->shdr[4].sh_size = debug_frame_size;
2671 
2672     img->shdr[5].sh_name = find_string(img->str, ".symtab");
2673     img->shdr[6].sh_name = find_string(img->str, ".strtab");
2674 
2675     img->sym[1].st_name = find_string(img->str, "code_gen_buffer");
2676     img->sym[1].st_value = buf;
2677     img->sym[1].st_size = buf_size;
2678 
2679     img->di.cu_low_pc = buf;
2680     img->di.cu_high_pc = buf + buf_size;
2681     img->di.fn_low_pc = buf;
2682     img->di.fn_high_pc = buf + buf_size;
2683 
2684     dfh = (DebugFrameHeader *)(img + 1);
2685     memcpy(dfh, debug_frame, debug_frame_size);
2686     dfh->fde.func_start = buf;
2687     dfh->fde.func_len = buf_size;
2688 
2689 #ifdef DEBUG_JIT
2690     /* Enable this block to be able to debug the ELF image file creation.
2691        One can use readelf, objdump, or other inspection utilities.  */
2692     {
2693         FILE *f = fopen("/tmp/qemu.jit", "w+b");
2694         if (f) {
2695             if (fwrite(img, img_size, 1, f) != img_size) {
2696                 /* Avoid stupid unused return value warning for fwrite.  */
2697             }
2698             fclose(f);
2699         }
2700     }
2701 #endif
2702 
2703     one_entry.symfile_addr = img;
2704     one_entry.symfile_size = img_size;
2705 
2706     __jit_debug_descriptor.action_flag = JIT_REGISTER_FN;
2707     __jit_debug_descriptor.relevant_entry = &one_entry;
2708     __jit_debug_descriptor.first_entry = &one_entry;
2709     __jit_debug_register_code();
2710 }
2711 #else
2712 /* No support for the feature.  Provide the entry point expected by exec.c,
2713    and implement the internal function we declared earlier.  */
2714 
2715 static void tcg_register_jit_int(void *buf, size_t size,
2716                                  const void *debug_frame,
2717                                  size_t debug_frame_size)
2718 {
2719 }
2720 
2721 void tcg_register_jit(void *buf, size_t buf_size)
2722 {
2723 }
2724 #endif /* ELF_HOST_MACHINE */
2725