xref: /openbmc/qemu/tcg/tcg.c (revision 2993683b)
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/cache-utils.h"
41 #include "qemu/host-utils.h"
42 #include "qemu/timer.h"
43 
44 /* Note: the long term plan is to reduce the dependancies on the QEMU
45    CPU definitions. Currently they are used for qemu_ld/st
46    instructions */
47 #define NO_CPU_IO_DEFS
48 #include "cpu.h"
49 
50 #include "tcg-op.h"
51 
52 #if TCG_TARGET_REG_BITS == 64
53 # define ELF_CLASS  ELFCLASS64
54 #else
55 # define ELF_CLASS  ELFCLASS32
56 #endif
57 #ifdef HOST_WORDS_BIGENDIAN
58 # define ELF_DATA   ELFDATA2MSB
59 #else
60 # define ELF_DATA   ELFDATA2LSB
61 #endif
62 
63 #include "elf.h"
64 
65 /* Forward declarations for functions declared in tcg-target.c and used here. */
66 static void tcg_target_init(TCGContext *s);
67 static void tcg_target_qemu_prologue(TCGContext *s);
68 static void patch_reloc(uint8_t *code_ptr, int type,
69                         tcg_target_long value, tcg_target_long addend);
70 
71 static void tcg_register_jit_int(void *buf, size_t size,
72                                  void *debug_frame, size_t debug_frame_size)
73     __attribute__((unused));
74 
75 /* Forward declarations for functions declared and used in tcg-target.c. */
76 static int target_parse_constraint(TCGArgConstraint *ct, const char **pct_str);
77 static void tcg_out_ld(TCGContext *s, TCGType type, TCGReg ret, TCGReg arg1,
78                        tcg_target_long arg2);
79 static void tcg_out_mov(TCGContext *s, TCGType type, TCGReg ret, TCGReg arg);
80 static void tcg_out_movi(TCGContext *s, TCGType type,
81                          TCGReg ret, tcg_target_long arg);
82 static void tcg_out_op(TCGContext *s, TCGOpcode opc, const TCGArg *args,
83                        const int *const_args);
84 static void tcg_out_st(TCGContext *s, TCGType type, TCGReg arg, TCGReg arg1,
85                        tcg_target_long arg2);
86 static int tcg_target_const_match(tcg_target_long val,
87                                   const TCGArgConstraint *arg_ct);
88 
89 TCGOpDef tcg_op_defs[] = {
90 #define DEF(s, oargs, iargs, cargs, flags) { #s, oargs, iargs, cargs, iargs + oargs + cargs, flags },
91 #include "tcg-opc.h"
92 #undef DEF
93 };
94 const size_t tcg_op_defs_max = ARRAY_SIZE(tcg_op_defs);
95 
96 static TCGRegSet tcg_target_available_regs[2];
97 static TCGRegSet tcg_target_call_clobber_regs;
98 
99 static inline void tcg_out8(TCGContext *s, uint8_t v)
100 {
101     *s->code_ptr++ = v;
102 }
103 
104 static inline void tcg_out16(TCGContext *s, uint16_t v)
105 {
106     *(uint16_t *)s->code_ptr = v;
107     s->code_ptr += 2;
108 }
109 
110 static inline void tcg_out32(TCGContext *s, uint32_t v)
111 {
112     *(uint32_t *)s->code_ptr = v;
113     s->code_ptr += 4;
114 }
115 
116 /* label relocation processing */
117 
118 static void tcg_out_reloc(TCGContext *s, uint8_t *code_ptr, int type,
119                           int label_index, long addend)
120 {
121     TCGLabel *l;
122     TCGRelocation *r;
123 
124     l = &s->labels[label_index];
125     if (l->has_value) {
126         /* FIXME: This may break relocations on RISC targets that
127            modify instruction fields in place.  The caller may not have
128            written the initial value.  */
129         patch_reloc(code_ptr, type, l->u.value, addend);
130     } else {
131         /* add a new relocation entry */
132         r = tcg_malloc(sizeof(TCGRelocation));
133         r->type = type;
134         r->ptr = code_ptr;
135         r->addend = addend;
136         r->next = l->u.first_reloc;
137         l->u.first_reloc = r;
138     }
139 }
140 
141 static void tcg_out_label(TCGContext *s, int label_index, void *ptr)
142 {
143     TCGLabel *l;
144     TCGRelocation *r;
145     tcg_target_long value = (tcg_target_long)ptr;
146 
147     l = &s->labels[label_index];
148     if (l->has_value)
149         tcg_abort();
150     r = l->u.first_reloc;
151     while (r != NULL) {
152         patch_reloc(r->ptr, r->type, value, r->addend);
153         r = r->next;
154     }
155     l->has_value = 1;
156     l->u.value = value;
157 }
158 
159 int gen_new_label(void)
160 {
161     TCGContext *s = &tcg_ctx;
162     int idx;
163     TCGLabel *l;
164 
165     if (s->nb_labels >= TCG_MAX_LABELS)
166         tcg_abort();
167     idx = s->nb_labels++;
168     l = &s->labels[idx];
169     l->has_value = 0;
170     l->u.first_reloc = NULL;
171     return idx;
172 }
173 
174 #include "tcg-target.c"
175 
176 /* pool based memory allocation */
177 void *tcg_malloc_internal(TCGContext *s, int size)
178 {
179     TCGPool *p;
180     int pool_size;
181 
182     if (size > TCG_POOL_CHUNK_SIZE) {
183         /* big malloc: insert a new pool (XXX: could optimize) */
184         p = g_malloc(sizeof(TCGPool) + size);
185         p->size = size;
186         p->next = s->pool_first_large;
187         s->pool_first_large = p;
188         return p->data;
189     } else {
190         p = s->pool_current;
191         if (!p) {
192             p = s->pool_first;
193             if (!p)
194                 goto new_pool;
195         } else {
196             if (!p->next) {
197             new_pool:
198                 pool_size = TCG_POOL_CHUNK_SIZE;
199                 p = g_malloc(sizeof(TCGPool) + pool_size);
200                 p->size = pool_size;
201                 p->next = NULL;
202                 if (s->pool_current)
203                     s->pool_current->next = p;
204                 else
205                     s->pool_first = p;
206             } else {
207                 p = p->next;
208             }
209         }
210     }
211     s->pool_current = p;
212     s->pool_cur = p->data + size;
213     s->pool_end = p->data + p->size;
214     return p->data;
215 }
216 
217 void tcg_pool_reset(TCGContext *s)
218 {
219     TCGPool *p, *t;
220     for (p = s->pool_first_large; p; p = t) {
221         t = p->next;
222         g_free(p);
223     }
224     s->pool_first_large = NULL;
225     s->pool_cur = s->pool_end = NULL;
226     s->pool_current = NULL;
227 }
228 
229 void tcg_context_init(TCGContext *s)
230 {
231     int op, total_args, n;
232     TCGOpDef *def;
233     TCGArgConstraint *args_ct;
234     int *sorted_args;
235 
236     memset(s, 0, sizeof(*s));
237     s->nb_globals = 0;
238 
239     /* Count total number of arguments and allocate the corresponding
240        space */
241     total_args = 0;
242     for(op = 0; op < NB_OPS; op++) {
243         def = &tcg_op_defs[op];
244         n = def->nb_iargs + def->nb_oargs;
245         total_args += n;
246     }
247 
248     args_ct = g_malloc(sizeof(TCGArgConstraint) * total_args);
249     sorted_args = g_malloc(sizeof(int) * total_args);
250 
251     for(op = 0; op < NB_OPS; op++) {
252         def = &tcg_op_defs[op];
253         def->args_ct = args_ct;
254         def->sorted_args = sorted_args;
255         n = def->nb_iargs + def->nb_oargs;
256         sorted_args += n;
257         args_ct += n;
258     }
259 
260     tcg_target_init(s);
261 }
262 
263 void tcg_prologue_init(TCGContext *s)
264 {
265     /* init global prologue and epilogue */
266     s->code_buf = s->code_gen_prologue;
267     s->code_ptr = s->code_buf;
268     tcg_target_qemu_prologue(s);
269     flush_icache_range((tcg_target_ulong)s->code_buf,
270                        (tcg_target_ulong)s->code_ptr);
271 
272 #ifdef DEBUG_DISAS
273     if (qemu_loglevel_mask(CPU_LOG_TB_OUT_ASM)) {
274         size_t size = s->code_ptr - s->code_buf;
275         qemu_log("PROLOGUE: [size=%zu]\n", size);
276         log_disas(s->code_buf, size);
277         qemu_log("\n");
278         qemu_log_flush();
279     }
280 #endif
281 }
282 
283 void tcg_set_frame(TCGContext *s, int reg,
284                    tcg_target_long start, tcg_target_long size)
285 {
286     s->frame_start = start;
287     s->frame_end = start + size;
288     s->frame_reg = reg;
289 }
290 
291 void tcg_func_start(TCGContext *s)
292 {
293     int i;
294     tcg_pool_reset(s);
295     s->nb_temps = s->nb_globals;
296     for(i = 0; i < (TCG_TYPE_COUNT * 2); i++)
297         s->first_free_temp[i] = -1;
298     s->labels = tcg_malloc(sizeof(TCGLabel) * TCG_MAX_LABELS);
299     s->nb_labels = 0;
300     s->current_frame_offset = s->frame_start;
301 
302 #ifdef CONFIG_DEBUG_TCG
303     s->goto_tb_issue_mask = 0;
304 #endif
305 
306     s->gen_opc_ptr = s->gen_opc_buf;
307     s->gen_opparam_ptr = s->gen_opparam_buf;
308 
309 #if defined(CONFIG_QEMU_LDST_OPTIMIZATION) && defined(CONFIG_SOFTMMU)
310     /* Initialize qemu_ld/st labels to assist code generation at the end of TB
311        for TLB miss cases at the end of TB */
312     s->qemu_ldst_labels = tcg_malloc(sizeof(TCGLabelQemuLdst) *
313                                      TCG_MAX_QEMU_LDST);
314     s->nb_qemu_ldst_labels = 0;
315 #endif
316 }
317 
318 static inline void tcg_temp_alloc(TCGContext *s, int n)
319 {
320     if (n > TCG_MAX_TEMPS)
321         tcg_abort();
322 }
323 
324 static inline int tcg_global_reg_new_internal(TCGType type, int reg,
325                                               const char *name)
326 {
327     TCGContext *s = &tcg_ctx;
328     TCGTemp *ts;
329     int idx;
330 
331 #if TCG_TARGET_REG_BITS == 32
332     if (type != TCG_TYPE_I32)
333         tcg_abort();
334 #endif
335     if (tcg_regset_test_reg(s->reserved_regs, reg))
336         tcg_abort();
337     idx = s->nb_globals;
338     tcg_temp_alloc(s, s->nb_globals + 1);
339     ts = &s->temps[s->nb_globals];
340     ts->base_type = type;
341     ts->type = type;
342     ts->fixed_reg = 1;
343     ts->reg = reg;
344     ts->name = name;
345     s->nb_globals++;
346     tcg_regset_set_reg(s->reserved_regs, reg);
347     return idx;
348 }
349 
350 TCGv_i32 tcg_global_reg_new_i32(int reg, const char *name)
351 {
352     int idx;
353 
354     idx = tcg_global_reg_new_internal(TCG_TYPE_I32, reg, name);
355     return MAKE_TCGV_I32(idx);
356 }
357 
358 TCGv_i64 tcg_global_reg_new_i64(int reg, const char *name)
359 {
360     int idx;
361 
362     idx = tcg_global_reg_new_internal(TCG_TYPE_I64, reg, name);
363     return MAKE_TCGV_I64(idx);
364 }
365 
366 static inline int tcg_global_mem_new_internal(TCGType type, int reg,
367                                               tcg_target_long offset,
368                                               const char *name)
369 {
370     TCGContext *s = &tcg_ctx;
371     TCGTemp *ts;
372     int idx;
373 
374     idx = s->nb_globals;
375 #if TCG_TARGET_REG_BITS == 32
376     if (type == TCG_TYPE_I64) {
377         char buf[64];
378         tcg_temp_alloc(s, s->nb_globals + 2);
379         ts = &s->temps[s->nb_globals];
380         ts->base_type = type;
381         ts->type = TCG_TYPE_I32;
382         ts->fixed_reg = 0;
383         ts->mem_allocated = 1;
384         ts->mem_reg = reg;
385 #ifdef TCG_TARGET_WORDS_BIGENDIAN
386         ts->mem_offset = offset + 4;
387 #else
388         ts->mem_offset = offset;
389 #endif
390         pstrcpy(buf, sizeof(buf), name);
391         pstrcat(buf, sizeof(buf), "_0");
392         ts->name = strdup(buf);
393         ts++;
394 
395         ts->base_type = type;
396         ts->type = TCG_TYPE_I32;
397         ts->fixed_reg = 0;
398         ts->mem_allocated = 1;
399         ts->mem_reg = reg;
400 #ifdef TCG_TARGET_WORDS_BIGENDIAN
401         ts->mem_offset = offset;
402 #else
403         ts->mem_offset = offset + 4;
404 #endif
405         pstrcpy(buf, sizeof(buf), name);
406         pstrcat(buf, sizeof(buf), "_1");
407         ts->name = strdup(buf);
408 
409         s->nb_globals += 2;
410     } else
411 #endif
412     {
413         tcg_temp_alloc(s, s->nb_globals + 1);
414         ts = &s->temps[s->nb_globals];
415         ts->base_type = type;
416         ts->type = type;
417         ts->fixed_reg = 0;
418         ts->mem_allocated = 1;
419         ts->mem_reg = reg;
420         ts->mem_offset = offset;
421         ts->name = name;
422         s->nb_globals++;
423     }
424     return idx;
425 }
426 
427 TCGv_i32 tcg_global_mem_new_i32(int reg, tcg_target_long offset,
428                                 const char *name)
429 {
430     int idx;
431 
432     idx = tcg_global_mem_new_internal(TCG_TYPE_I32, reg, offset, name);
433     return MAKE_TCGV_I32(idx);
434 }
435 
436 TCGv_i64 tcg_global_mem_new_i64(int reg, tcg_target_long offset,
437                                 const char *name)
438 {
439     int idx;
440 
441     idx = tcg_global_mem_new_internal(TCG_TYPE_I64, reg, offset, name);
442     return MAKE_TCGV_I64(idx);
443 }
444 
445 static inline int tcg_temp_new_internal(TCGType type, int temp_local)
446 {
447     TCGContext *s = &tcg_ctx;
448     TCGTemp *ts;
449     int idx, k;
450 
451     k = type;
452     if (temp_local)
453         k += TCG_TYPE_COUNT;
454     idx = s->first_free_temp[k];
455     if (idx != -1) {
456         /* There is already an available temp with the
457            right type */
458         ts = &s->temps[idx];
459         s->first_free_temp[k] = ts->next_free_temp;
460         ts->temp_allocated = 1;
461         assert(ts->temp_local == temp_local);
462     } else {
463         idx = s->nb_temps;
464 #if TCG_TARGET_REG_BITS == 32
465         if (type == TCG_TYPE_I64) {
466             tcg_temp_alloc(s, s->nb_temps + 2);
467             ts = &s->temps[s->nb_temps];
468             ts->base_type = type;
469             ts->type = TCG_TYPE_I32;
470             ts->temp_allocated = 1;
471             ts->temp_local = temp_local;
472             ts->name = NULL;
473             ts++;
474             ts->base_type = TCG_TYPE_I32;
475             ts->type = TCG_TYPE_I32;
476             ts->temp_allocated = 1;
477             ts->temp_local = temp_local;
478             ts->name = NULL;
479             s->nb_temps += 2;
480         } else
481 #endif
482         {
483             tcg_temp_alloc(s, s->nb_temps + 1);
484             ts = &s->temps[s->nb_temps];
485             ts->base_type = type;
486             ts->type = type;
487             ts->temp_allocated = 1;
488             ts->temp_local = temp_local;
489             ts->name = NULL;
490             s->nb_temps++;
491         }
492     }
493 
494 #if defined(CONFIG_DEBUG_TCG)
495     s->temps_in_use++;
496 #endif
497     return idx;
498 }
499 
500 TCGv_i32 tcg_temp_new_internal_i32(int temp_local)
501 {
502     int idx;
503 
504     idx = tcg_temp_new_internal(TCG_TYPE_I32, temp_local);
505     return MAKE_TCGV_I32(idx);
506 }
507 
508 TCGv_i64 tcg_temp_new_internal_i64(int temp_local)
509 {
510     int idx;
511 
512     idx = tcg_temp_new_internal(TCG_TYPE_I64, temp_local);
513     return MAKE_TCGV_I64(idx);
514 }
515 
516 static inline void tcg_temp_free_internal(int idx)
517 {
518     TCGContext *s = &tcg_ctx;
519     TCGTemp *ts;
520     int k;
521 
522 #if defined(CONFIG_DEBUG_TCG)
523     s->temps_in_use--;
524     if (s->temps_in_use < 0) {
525         fprintf(stderr, "More temporaries freed than allocated!\n");
526     }
527 #endif
528 
529     assert(idx >= s->nb_globals && idx < s->nb_temps);
530     ts = &s->temps[idx];
531     assert(ts->temp_allocated != 0);
532     ts->temp_allocated = 0;
533     k = ts->base_type;
534     if (ts->temp_local)
535         k += TCG_TYPE_COUNT;
536     ts->next_free_temp = s->first_free_temp[k];
537     s->first_free_temp[k] = idx;
538 }
539 
540 void tcg_temp_free_i32(TCGv_i32 arg)
541 {
542     tcg_temp_free_internal(GET_TCGV_I32(arg));
543 }
544 
545 void tcg_temp_free_i64(TCGv_i64 arg)
546 {
547     tcg_temp_free_internal(GET_TCGV_I64(arg));
548 }
549 
550 TCGv_i32 tcg_const_i32(int32_t val)
551 {
552     TCGv_i32 t0;
553     t0 = tcg_temp_new_i32();
554     tcg_gen_movi_i32(t0, val);
555     return t0;
556 }
557 
558 TCGv_i64 tcg_const_i64(int64_t val)
559 {
560     TCGv_i64 t0;
561     t0 = tcg_temp_new_i64();
562     tcg_gen_movi_i64(t0, val);
563     return t0;
564 }
565 
566 TCGv_i32 tcg_const_local_i32(int32_t val)
567 {
568     TCGv_i32 t0;
569     t0 = tcg_temp_local_new_i32();
570     tcg_gen_movi_i32(t0, val);
571     return t0;
572 }
573 
574 TCGv_i64 tcg_const_local_i64(int64_t val)
575 {
576     TCGv_i64 t0;
577     t0 = tcg_temp_local_new_i64();
578     tcg_gen_movi_i64(t0, val);
579     return t0;
580 }
581 
582 #if defined(CONFIG_DEBUG_TCG)
583 void tcg_clear_temp_count(void)
584 {
585     TCGContext *s = &tcg_ctx;
586     s->temps_in_use = 0;
587 }
588 
589 int tcg_check_temp_count(void)
590 {
591     TCGContext *s = &tcg_ctx;
592     if (s->temps_in_use) {
593         /* Clear the count so that we don't give another
594          * warning immediately next time around.
595          */
596         s->temps_in_use = 0;
597         return 1;
598     }
599     return 0;
600 }
601 #endif
602 
603 void tcg_register_helper(void *func, const char *name)
604 {
605     TCGContext *s = &tcg_ctx;
606     int n;
607     if ((s->nb_helpers + 1) > s->allocated_helpers) {
608         n = s->allocated_helpers;
609         if (n == 0) {
610             n = 4;
611         } else {
612             n *= 2;
613         }
614         s->helpers = realloc(s->helpers, n * sizeof(TCGHelperInfo));
615         s->allocated_helpers = n;
616     }
617     s->helpers[s->nb_helpers].func = (tcg_target_ulong)func;
618     s->helpers[s->nb_helpers].name = name;
619     s->nb_helpers++;
620 }
621 
622 /* Note: we convert the 64 bit args to 32 bit and do some alignment
623    and endian swap. Maybe it would be better to do the alignment
624    and endian swap in tcg_reg_alloc_call(). */
625 void tcg_gen_callN(TCGContext *s, TCGv_ptr func, unsigned int flags,
626                    int sizemask, TCGArg ret, int nargs, TCGArg *args)
627 {
628     int i;
629     int real_args;
630     int nb_rets;
631     TCGArg *nparam;
632 
633 #if defined(TCG_TARGET_EXTEND_ARGS) && TCG_TARGET_REG_BITS == 64
634     for (i = 0; i < nargs; ++i) {
635         int is_64bit = sizemask & (1 << (i+1)*2);
636         int is_signed = sizemask & (2 << (i+1)*2);
637         if (!is_64bit) {
638             TCGv_i64 temp = tcg_temp_new_i64();
639             TCGv_i64 orig = MAKE_TCGV_I64(args[i]);
640             if (is_signed) {
641                 tcg_gen_ext32s_i64(temp, orig);
642             } else {
643                 tcg_gen_ext32u_i64(temp, orig);
644             }
645             args[i] = GET_TCGV_I64(temp);
646         }
647     }
648 #endif /* TCG_TARGET_EXTEND_ARGS */
649 
650     *s->gen_opc_ptr++ = INDEX_op_call;
651     nparam = s->gen_opparam_ptr++;
652     if (ret != TCG_CALL_DUMMY_ARG) {
653 #if TCG_TARGET_REG_BITS < 64
654         if (sizemask & 1) {
655 #ifdef TCG_TARGET_WORDS_BIGENDIAN
656             *s->gen_opparam_ptr++ = ret + 1;
657             *s->gen_opparam_ptr++ = ret;
658 #else
659             *s->gen_opparam_ptr++ = ret;
660             *s->gen_opparam_ptr++ = ret + 1;
661 #endif
662             nb_rets = 2;
663         } else
664 #endif
665         {
666             *s->gen_opparam_ptr++ = ret;
667             nb_rets = 1;
668         }
669     } else {
670         nb_rets = 0;
671     }
672     real_args = 0;
673     for (i = 0; i < nargs; i++) {
674 #if TCG_TARGET_REG_BITS < 64
675         int is_64bit = sizemask & (1 << (i+1)*2);
676         if (is_64bit) {
677 #ifdef TCG_TARGET_CALL_ALIGN_ARGS
678             /* some targets want aligned 64 bit args */
679             if (real_args & 1) {
680                 *s->gen_opparam_ptr++ = TCG_CALL_DUMMY_ARG;
681                 real_args++;
682             }
683 #endif
684 	    /* If stack grows up, then we will be placing successive
685 	       arguments at lower addresses, which means we need to
686 	       reverse the order compared to how we would normally
687 	       treat either big or little-endian.  For those arguments
688 	       that will wind up in registers, this still works for
689 	       HPPA (the only current STACK_GROWSUP target) since the
690 	       argument registers are *also* allocated in decreasing
691 	       order.  If another such target is added, this logic may
692 	       have to get more complicated to differentiate between
693 	       stack arguments and register arguments.  */
694 #if defined(TCG_TARGET_WORDS_BIGENDIAN) != defined(TCG_TARGET_STACK_GROWSUP)
695             *s->gen_opparam_ptr++ = args[i] + 1;
696             *s->gen_opparam_ptr++ = args[i];
697 #else
698             *s->gen_opparam_ptr++ = args[i];
699             *s->gen_opparam_ptr++ = args[i] + 1;
700 #endif
701             real_args += 2;
702             continue;
703         }
704 #endif /* TCG_TARGET_REG_BITS < 64 */
705 
706         *s->gen_opparam_ptr++ = args[i];
707         real_args++;
708     }
709     *s->gen_opparam_ptr++ = GET_TCGV_PTR(func);
710 
711     *s->gen_opparam_ptr++ = flags;
712 
713     *nparam = (nb_rets << 16) | (real_args + 1);
714 
715     /* total parameters, needed to go backward in the instruction stream */
716     *s->gen_opparam_ptr++ = 1 + nb_rets + real_args + 3;
717 
718 #if defined(TCG_TARGET_EXTEND_ARGS) && TCG_TARGET_REG_BITS == 64
719     for (i = 0; i < nargs; ++i) {
720         int is_64bit = sizemask & (1 << (i+1)*2);
721         if (!is_64bit) {
722             TCGv_i64 temp = MAKE_TCGV_I64(args[i]);
723             tcg_temp_free_i64(temp);
724         }
725     }
726 #endif /* TCG_TARGET_EXTEND_ARGS */
727 }
728 
729 #if TCG_TARGET_REG_BITS == 32
730 void tcg_gen_shifti_i64(TCGv_i64 ret, TCGv_i64 arg1,
731                         int c, int right, int arith)
732 {
733     if (c == 0) {
734         tcg_gen_mov_i32(TCGV_LOW(ret), TCGV_LOW(arg1));
735         tcg_gen_mov_i32(TCGV_HIGH(ret), TCGV_HIGH(arg1));
736     } else if (c >= 32) {
737         c -= 32;
738         if (right) {
739             if (arith) {
740                 tcg_gen_sari_i32(TCGV_LOW(ret), TCGV_HIGH(arg1), c);
741                 tcg_gen_sari_i32(TCGV_HIGH(ret), TCGV_HIGH(arg1), 31);
742             } else {
743                 tcg_gen_shri_i32(TCGV_LOW(ret), TCGV_HIGH(arg1), c);
744                 tcg_gen_movi_i32(TCGV_HIGH(ret), 0);
745             }
746         } else {
747             tcg_gen_shli_i32(TCGV_HIGH(ret), TCGV_LOW(arg1), c);
748             tcg_gen_movi_i32(TCGV_LOW(ret), 0);
749         }
750     } else {
751         TCGv_i32 t0, t1;
752 
753         t0 = tcg_temp_new_i32();
754         t1 = tcg_temp_new_i32();
755         if (right) {
756             tcg_gen_shli_i32(t0, TCGV_HIGH(arg1), 32 - c);
757             if (arith)
758                 tcg_gen_sari_i32(t1, TCGV_HIGH(arg1), c);
759             else
760                 tcg_gen_shri_i32(t1, TCGV_HIGH(arg1), c);
761             tcg_gen_shri_i32(TCGV_LOW(ret), TCGV_LOW(arg1), c);
762             tcg_gen_or_i32(TCGV_LOW(ret), TCGV_LOW(ret), t0);
763             tcg_gen_mov_i32(TCGV_HIGH(ret), t1);
764         } else {
765             tcg_gen_shri_i32(t0, TCGV_LOW(arg1), 32 - c);
766             /* Note: ret can be the same as arg1, so we use t1 */
767             tcg_gen_shli_i32(t1, TCGV_LOW(arg1), c);
768             tcg_gen_shli_i32(TCGV_HIGH(ret), TCGV_HIGH(arg1), c);
769             tcg_gen_or_i32(TCGV_HIGH(ret), TCGV_HIGH(ret), t0);
770             tcg_gen_mov_i32(TCGV_LOW(ret), t1);
771         }
772         tcg_temp_free_i32(t0);
773         tcg_temp_free_i32(t1);
774     }
775 }
776 #endif
777 
778 
779 static void tcg_reg_alloc_start(TCGContext *s)
780 {
781     int i;
782     TCGTemp *ts;
783     for(i = 0; i < s->nb_globals; i++) {
784         ts = &s->temps[i];
785         if (ts->fixed_reg) {
786             ts->val_type = TEMP_VAL_REG;
787         } else {
788             ts->val_type = TEMP_VAL_MEM;
789         }
790     }
791     for(i = s->nb_globals; i < s->nb_temps; i++) {
792         ts = &s->temps[i];
793         if (ts->temp_local) {
794             ts->val_type = TEMP_VAL_MEM;
795         } else {
796             ts->val_type = TEMP_VAL_DEAD;
797         }
798         ts->mem_allocated = 0;
799         ts->fixed_reg = 0;
800     }
801     for(i = 0; i < TCG_TARGET_NB_REGS; i++) {
802         s->reg_to_temp[i] = -1;
803     }
804 }
805 
806 static char *tcg_get_arg_str_idx(TCGContext *s, char *buf, int buf_size,
807                                  int idx)
808 {
809     TCGTemp *ts;
810 
811     assert(idx >= 0 && idx < s->nb_temps);
812     ts = &s->temps[idx];
813     if (idx < s->nb_globals) {
814         pstrcpy(buf, buf_size, ts->name);
815     } else {
816         if (ts->temp_local)
817             snprintf(buf, buf_size, "loc%d", idx - s->nb_globals);
818         else
819             snprintf(buf, buf_size, "tmp%d", idx - s->nb_globals);
820     }
821     return buf;
822 }
823 
824 char *tcg_get_arg_str_i32(TCGContext *s, char *buf, int buf_size, TCGv_i32 arg)
825 {
826     return tcg_get_arg_str_idx(s, buf, buf_size, GET_TCGV_I32(arg));
827 }
828 
829 char *tcg_get_arg_str_i64(TCGContext *s, char *buf, int buf_size, TCGv_i64 arg)
830 {
831     return tcg_get_arg_str_idx(s, buf, buf_size, GET_TCGV_I64(arg));
832 }
833 
834 static int helper_cmp(const void *p1, const void *p2)
835 {
836     const TCGHelperInfo *th1 = p1;
837     const TCGHelperInfo *th2 = p2;
838     if (th1->func < th2->func)
839         return -1;
840     else if (th1->func == th2->func)
841         return 0;
842     else
843         return 1;
844 }
845 
846 /* find helper definition (Note: A hash table would be better) */
847 static TCGHelperInfo *tcg_find_helper(TCGContext *s, tcg_target_ulong val)
848 {
849     int m, m_min, m_max;
850     TCGHelperInfo *th;
851     tcg_target_ulong v;
852 
853     if (unlikely(!s->helpers_sorted)) {
854         qsort(s->helpers, s->nb_helpers, sizeof(TCGHelperInfo),
855               helper_cmp);
856         s->helpers_sorted = 1;
857     }
858 
859     /* binary search */
860     m_min = 0;
861     m_max = s->nb_helpers - 1;
862     while (m_min <= m_max) {
863         m = (m_min + m_max) >> 1;
864         th = &s->helpers[m];
865         v = th->func;
866         if (v == val)
867             return th;
868         else if (val < v) {
869             m_max = m - 1;
870         } else {
871             m_min = m + 1;
872         }
873     }
874     return NULL;
875 }
876 
877 static const char * const cond_name[] =
878 {
879     [TCG_COND_NEVER] = "never",
880     [TCG_COND_ALWAYS] = "always",
881     [TCG_COND_EQ] = "eq",
882     [TCG_COND_NE] = "ne",
883     [TCG_COND_LT] = "lt",
884     [TCG_COND_GE] = "ge",
885     [TCG_COND_LE] = "le",
886     [TCG_COND_GT] = "gt",
887     [TCG_COND_LTU] = "ltu",
888     [TCG_COND_GEU] = "geu",
889     [TCG_COND_LEU] = "leu",
890     [TCG_COND_GTU] = "gtu"
891 };
892 
893 void tcg_dump_ops(TCGContext *s)
894 {
895     const uint16_t *opc_ptr;
896     const TCGArg *args;
897     TCGArg arg;
898     TCGOpcode c;
899     int i, k, nb_oargs, nb_iargs, nb_cargs, first_insn;
900     const TCGOpDef *def;
901     char buf[128];
902 
903     first_insn = 1;
904     opc_ptr = s->gen_opc_buf;
905     args = s->gen_opparam_buf;
906     while (opc_ptr < s->gen_opc_ptr) {
907         c = *opc_ptr++;
908         def = &tcg_op_defs[c];
909         if (c == INDEX_op_debug_insn_start) {
910             uint64_t pc;
911 #if TARGET_LONG_BITS > TCG_TARGET_REG_BITS
912             pc = ((uint64_t)args[1] << 32) | args[0];
913 #else
914             pc = args[0];
915 #endif
916             if (!first_insn) {
917                 qemu_log("\n");
918             }
919             qemu_log(" ---- 0x%" PRIx64, pc);
920             first_insn = 0;
921             nb_oargs = def->nb_oargs;
922             nb_iargs = def->nb_iargs;
923             nb_cargs = def->nb_cargs;
924         } else if (c == INDEX_op_call) {
925             TCGArg arg;
926 
927             /* variable number of arguments */
928             arg = *args++;
929             nb_oargs = arg >> 16;
930             nb_iargs = arg & 0xffff;
931             nb_cargs = def->nb_cargs;
932 
933             qemu_log(" %s ", def->name);
934 
935             /* function name */
936             qemu_log("%s",
937                      tcg_get_arg_str_idx(s, buf, sizeof(buf),
938                                          args[nb_oargs + nb_iargs - 1]));
939             /* flags */
940             qemu_log(",$0x%" TCG_PRIlx, args[nb_oargs + nb_iargs]);
941             /* nb out args */
942             qemu_log(",$%d", nb_oargs);
943             for(i = 0; i < nb_oargs; i++) {
944                 qemu_log(",");
945                 qemu_log("%s", tcg_get_arg_str_idx(s, buf, sizeof(buf),
946                                                    args[i]));
947             }
948             for(i = 0; i < (nb_iargs - 1); i++) {
949                 qemu_log(",");
950                 if (args[nb_oargs + i] == TCG_CALL_DUMMY_ARG) {
951                     qemu_log("<dummy>");
952                 } else {
953                     qemu_log("%s", tcg_get_arg_str_idx(s, buf, sizeof(buf),
954                                                        args[nb_oargs + i]));
955                 }
956             }
957         } else if (c == INDEX_op_movi_i32 || c == INDEX_op_movi_i64) {
958             tcg_target_ulong val;
959             TCGHelperInfo *th;
960 
961             nb_oargs = def->nb_oargs;
962             nb_iargs = def->nb_iargs;
963             nb_cargs = def->nb_cargs;
964             qemu_log(" %s %s,$", def->name,
965                      tcg_get_arg_str_idx(s, buf, sizeof(buf), args[0]));
966             val = args[1];
967             th = tcg_find_helper(s, val);
968             if (th) {
969                 qemu_log("%s", th->name);
970             } else {
971                 if (c == INDEX_op_movi_i32) {
972                     qemu_log("0x%x", (uint32_t)val);
973                 } else {
974                     qemu_log("0x%" PRIx64 , (uint64_t)val);
975                 }
976             }
977         } else {
978             qemu_log(" %s ", def->name);
979             if (c == INDEX_op_nopn) {
980                 /* variable number of arguments */
981                 nb_cargs = *args;
982                 nb_oargs = 0;
983                 nb_iargs = 0;
984             } else {
985                 nb_oargs = def->nb_oargs;
986                 nb_iargs = def->nb_iargs;
987                 nb_cargs = def->nb_cargs;
988             }
989 
990             k = 0;
991             for(i = 0; i < nb_oargs; i++) {
992                 if (k != 0) {
993                     qemu_log(",");
994                 }
995                 qemu_log("%s", tcg_get_arg_str_idx(s, buf, sizeof(buf),
996                                                    args[k++]));
997             }
998             for(i = 0; i < nb_iargs; i++) {
999                 if (k != 0) {
1000                     qemu_log(",");
1001                 }
1002                 qemu_log("%s", tcg_get_arg_str_idx(s, buf, sizeof(buf),
1003                                                    args[k++]));
1004             }
1005             switch (c) {
1006             case INDEX_op_brcond_i32:
1007             case INDEX_op_setcond_i32:
1008             case INDEX_op_movcond_i32:
1009             case INDEX_op_brcond2_i32:
1010             case INDEX_op_setcond2_i32:
1011             case INDEX_op_brcond_i64:
1012             case INDEX_op_setcond_i64:
1013             case INDEX_op_movcond_i64:
1014                 if (args[k] < ARRAY_SIZE(cond_name) && cond_name[args[k]]) {
1015                     qemu_log(",%s", cond_name[args[k++]]);
1016                 } else {
1017                     qemu_log(",$0x%" TCG_PRIlx, args[k++]);
1018                 }
1019                 i = 1;
1020                 break;
1021             default:
1022                 i = 0;
1023                 break;
1024             }
1025             for(; i < nb_cargs; i++) {
1026                 if (k != 0) {
1027                     qemu_log(",");
1028                 }
1029                 arg = args[k++];
1030                 qemu_log("$0x%" TCG_PRIlx, arg);
1031             }
1032         }
1033         qemu_log("\n");
1034         args += nb_iargs + nb_oargs + nb_cargs;
1035     }
1036 }
1037 
1038 /* we give more priority to constraints with less registers */
1039 static int get_constraint_priority(const TCGOpDef *def, int k)
1040 {
1041     const TCGArgConstraint *arg_ct;
1042 
1043     int i, n;
1044     arg_ct = &def->args_ct[k];
1045     if (arg_ct->ct & TCG_CT_ALIAS) {
1046         /* an alias is equivalent to a single register */
1047         n = 1;
1048     } else {
1049         if (!(arg_ct->ct & TCG_CT_REG))
1050             return 0;
1051         n = 0;
1052         for(i = 0; i < TCG_TARGET_NB_REGS; i++) {
1053             if (tcg_regset_test_reg(arg_ct->u.regs, i))
1054                 n++;
1055         }
1056     }
1057     return TCG_TARGET_NB_REGS - n + 1;
1058 }
1059 
1060 /* sort from highest priority to lowest */
1061 static void sort_constraints(TCGOpDef *def, int start, int n)
1062 {
1063     int i, j, p1, p2, tmp;
1064 
1065     for(i = 0; i < n; i++)
1066         def->sorted_args[start + i] = start + i;
1067     if (n <= 1)
1068         return;
1069     for(i = 0; i < n - 1; i++) {
1070         for(j = i + 1; j < n; j++) {
1071             p1 = get_constraint_priority(def, def->sorted_args[start + i]);
1072             p2 = get_constraint_priority(def, def->sorted_args[start + j]);
1073             if (p1 < p2) {
1074                 tmp = def->sorted_args[start + i];
1075                 def->sorted_args[start + i] = def->sorted_args[start + j];
1076                 def->sorted_args[start + j] = tmp;
1077             }
1078         }
1079     }
1080 }
1081 
1082 void tcg_add_target_add_op_defs(const TCGTargetOpDef *tdefs)
1083 {
1084     TCGOpcode op;
1085     TCGOpDef *def;
1086     const char *ct_str;
1087     int i, nb_args;
1088 
1089     for(;;) {
1090         if (tdefs->op == (TCGOpcode)-1)
1091             break;
1092         op = tdefs->op;
1093         assert((unsigned)op < NB_OPS);
1094         def = &tcg_op_defs[op];
1095 #if defined(CONFIG_DEBUG_TCG)
1096         /* Duplicate entry in op definitions? */
1097         assert(!def->used);
1098         def->used = 1;
1099 #endif
1100         nb_args = def->nb_iargs + def->nb_oargs;
1101         for(i = 0; i < nb_args; i++) {
1102             ct_str = tdefs->args_ct_str[i];
1103             /* Incomplete TCGTargetOpDef entry? */
1104             assert(ct_str != NULL);
1105             tcg_regset_clear(def->args_ct[i].u.regs);
1106             def->args_ct[i].ct = 0;
1107             if (ct_str[0] >= '0' && ct_str[0] <= '9') {
1108                 int oarg;
1109                 oarg = ct_str[0] - '0';
1110                 assert(oarg < def->nb_oargs);
1111                 assert(def->args_ct[oarg].ct & TCG_CT_REG);
1112                 /* TCG_CT_ALIAS is for the output arguments. The input
1113                    argument is tagged with TCG_CT_IALIAS. */
1114                 def->args_ct[i] = def->args_ct[oarg];
1115                 def->args_ct[oarg].ct = TCG_CT_ALIAS;
1116                 def->args_ct[oarg].alias_index = i;
1117                 def->args_ct[i].ct |= TCG_CT_IALIAS;
1118                 def->args_ct[i].alias_index = oarg;
1119             } else {
1120                 for(;;) {
1121                     if (*ct_str == '\0')
1122                         break;
1123                     switch(*ct_str) {
1124                     case 'i':
1125                         def->args_ct[i].ct |= TCG_CT_CONST;
1126                         ct_str++;
1127                         break;
1128                     default:
1129                         if (target_parse_constraint(&def->args_ct[i], &ct_str) < 0) {
1130                             fprintf(stderr, "Invalid constraint '%s' for arg %d of operation '%s'\n",
1131                                     ct_str, i, def->name);
1132                             exit(1);
1133                         }
1134                     }
1135                 }
1136             }
1137         }
1138 
1139         /* TCGTargetOpDef entry with too much information? */
1140         assert(i == TCG_MAX_OP_ARGS || tdefs->args_ct_str[i] == NULL);
1141 
1142         /* sort the constraints (XXX: this is just an heuristic) */
1143         sort_constraints(def, 0, def->nb_oargs);
1144         sort_constraints(def, def->nb_oargs, def->nb_iargs);
1145 
1146 #if 0
1147         {
1148             int i;
1149 
1150             printf("%s: sorted=", def->name);
1151             for(i = 0; i < def->nb_oargs + def->nb_iargs; i++)
1152                 printf(" %d", def->sorted_args[i]);
1153             printf("\n");
1154         }
1155 #endif
1156         tdefs++;
1157     }
1158 
1159 #if defined(CONFIG_DEBUG_TCG)
1160     i = 0;
1161     for (op = 0; op < ARRAY_SIZE(tcg_op_defs); op++) {
1162         const TCGOpDef *def = &tcg_op_defs[op];
1163         if (op < INDEX_op_call
1164             || op == INDEX_op_debug_insn_start
1165             || (def->flags & TCG_OPF_NOT_PRESENT)) {
1166             /* Wrong entry in op definitions? */
1167             if (def->used) {
1168                 fprintf(stderr, "Invalid op definition for %s\n", def->name);
1169                 i = 1;
1170             }
1171         } else {
1172             /* Missing entry in op definitions? */
1173             if (!def->used) {
1174                 fprintf(stderr, "Missing op definition for %s\n", def->name);
1175                 i = 1;
1176             }
1177         }
1178     }
1179     if (i == 1) {
1180         tcg_abort();
1181     }
1182 #endif
1183 }
1184 
1185 #ifdef USE_LIVENESS_ANALYSIS
1186 
1187 /* set a nop for an operation using 'nb_args' */
1188 static inline void tcg_set_nop(TCGContext *s, uint16_t *opc_ptr,
1189                                TCGArg *args, int nb_args)
1190 {
1191     if (nb_args == 0) {
1192         *opc_ptr = INDEX_op_nop;
1193     } else {
1194         *opc_ptr = INDEX_op_nopn;
1195         args[0] = nb_args;
1196         args[nb_args - 1] = nb_args;
1197     }
1198 }
1199 
1200 /* liveness analysis: end of function: all temps are dead, and globals
1201    should be in memory. */
1202 static inline void tcg_la_func_end(TCGContext *s, uint8_t *dead_temps,
1203                                    uint8_t *mem_temps)
1204 {
1205     memset(dead_temps, 1, s->nb_temps);
1206     memset(mem_temps, 1, s->nb_globals);
1207     memset(mem_temps + s->nb_globals, 0, s->nb_temps - s->nb_globals);
1208 }
1209 
1210 /* liveness analysis: end of basic block: all temps are dead, globals
1211    and local temps should be in memory. */
1212 static inline void tcg_la_bb_end(TCGContext *s, uint8_t *dead_temps,
1213                                  uint8_t *mem_temps)
1214 {
1215     int i;
1216 
1217     memset(dead_temps, 1, s->nb_temps);
1218     memset(mem_temps, 1, s->nb_globals);
1219     for(i = s->nb_globals; i < s->nb_temps; i++) {
1220         mem_temps[i] = s->temps[i].temp_local;
1221     }
1222 }
1223 
1224 /* Liveness analysis : update the opc_dead_args array to tell if a
1225    given input arguments is dead. Instructions updating dead
1226    temporaries are removed. */
1227 static void tcg_liveness_analysis(TCGContext *s)
1228 {
1229     int i, op_index, nb_args, nb_iargs, nb_oargs, arg, nb_ops;
1230     TCGOpcode op, op_new;
1231     TCGArg *args;
1232     const TCGOpDef *def;
1233     uint8_t *dead_temps, *mem_temps;
1234     uint16_t dead_args;
1235     uint8_t sync_args;
1236 
1237     s->gen_opc_ptr++; /* skip end */
1238 
1239     nb_ops = s->gen_opc_ptr - s->gen_opc_buf;
1240 
1241     s->op_dead_args = tcg_malloc(nb_ops * sizeof(uint16_t));
1242     s->op_sync_args = tcg_malloc(nb_ops * sizeof(uint8_t));
1243 
1244     dead_temps = tcg_malloc(s->nb_temps);
1245     mem_temps = tcg_malloc(s->nb_temps);
1246     tcg_la_func_end(s, dead_temps, mem_temps);
1247 
1248     args = s->gen_opparam_ptr;
1249     op_index = nb_ops - 1;
1250     while (op_index >= 0) {
1251         op = s->gen_opc_buf[op_index];
1252         def = &tcg_op_defs[op];
1253         switch(op) {
1254         case INDEX_op_call:
1255             {
1256                 int call_flags;
1257 
1258                 nb_args = args[-1];
1259                 args -= nb_args;
1260                 nb_iargs = args[0] & 0xffff;
1261                 nb_oargs = args[0] >> 16;
1262                 args++;
1263                 call_flags = args[nb_oargs + nb_iargs];
1264 
1265                 /* pure functions can be removed if their result is not
1266                    used */
1267                 if (call_flags & TCG_CALL_NO_SIDE_EFFECTS) {
1268                     for(i = 0; i < nb_oargs; i++) {
1269                         arg = args[i];
1270                         if (!dead_temps[arg] || mem_temps[arg]) {
1271                             goto do_not_remove_call;
1272                         }
1273                     }
1274                     tcg_set_nop(s, s->gen_opc_buf + op_index,
1275                                 args - 1, nb_args);
1276                 } else {
1277                 do_not_remove_call:
1278 
1279                     /* output args are dead */
1280                     dead_args = 0;
1281                     sync_args = 0;
1282                     for(i = 0; i < nb_oargs; i++) {
1283                         arg = args[i];
1284                         if (dead_temps[arg]) {
1285                             dead_args |= (1 << i);
1286                         }
1287                         if (mem_temps[arg]) {
1288                             sync_args |= (1 << i);
1289                         }
1290                         dead_temps[arg] = 1;
1291                         mem_temps[arg] = 0;
1292                     }
1293 
1294                     if (!(call_flags & TCG_CALL_NO_READ_GLOBALS)) {
1295                         /* globals should be synced to memory */
1296                         memset(mem_temps, 1, s->nb_globals);
1297                     }
1298                     if (!(call_flags & (TCG_CALL_NO_WRITE_GLOBALS |
1299                                         TCG_CALL_NO_READ_GLOBALS))) {
1300                         /* globals should go back to memory */
1301                         memset(dead_temps, 1, s->nb_globals);
1302                     }
1303 
1304                     /* input args are live */
1305                     for(i = nb_oargs; i < nb_iargs + nb_oargs; i++) {
1306                         arg = args[i];
1307                         if (arg != TCG_CALL_DUMMY_ARG) {
1308                             if (dead_temps[arg]) {
1309                                 dead_args |= (1 << i);
1310                             }
1311                             dead_temps[arg] = 0;
1312                         }
1313                     }
1314                     s->op_dead_args[op_index] = dead_args;
1315                     s->op_sync_args[op_index] = sync_args;
1316                 }
1317                 args--;
1318             }
1319             break;
1320         case INDEX_op_debug_insn_start:
1321             args -= def->nb_args;
1322             break;
1323         case INDEX_op_nopn:
1324             nb_args = args[-1];
1325             args -= nb_args;
1326             break;
1327         case INDEX_op_discard:
1328             args--;
1329             /* mark the temporary as dead */
1330             dead_temps[args[0]] = 1;
1331             mem_temps[args[0]] = 0;
1332             break;
1333         case INDEX_op_end:
1334             break;
1335 
1336         case INDEX_op_add2_i32:
1337             op_new = INDEX_op_add_i32;
1338             goto do_addsub2;
1339         case INDEX_op_sub2_i32:
1340             op_new = INDEX_op_sub_i32;
1341             goto do_addsub2;
1342         case INDEX_op_add2_i64:
1343             op_new = INDEX_op_add_i64;
1344             goto do_addsub2;
1345         case INDEX_op_sub2_i64:
1346             op_new = INDEX_op_sub_i64;
1347         do_addsub2:
1348             args -= 6;
1349             nb_iargs = 4;
1350             nb_oargs = 2;
1351             /* Test if the high part of the operation is dead, but not
1352                the low part.  The result can be optimized to a simple
1353                add or sub.  This happens often for x86_64 guest when the
1354                cpu mode is set to 32 bit.  */
1355             if (dead_temps[args[1]] && !mem_temps[args[1]]) {
1356                 if (dead_temps[args[0]] && !mem_temps[args[0]]) {
1357                     goto do_remove;
1358                 }
1359                 /* Create the single operation plus nop.  */
1360                 s->gen_opc_buf[op_index] = op = op_new;
1361                 args[1] = args[2];
1362                 args[2] = args[4];
1363                 assert(s->gen_opc_buf[op_index + 1] == INDEX_op_nop);
1364                 tcg_set_nop(s, s->gen_opc_buf + op_index + 1, args + 3, 3);
1365                 /* Fall through and mark the single-word operation live.  */
1366                 nb_iargs = 2;
1367                 nb_oargs = 1;
1368             }
1369             goto do_not_remove;
1370 
1371         case INDEX_op_mulu2_i32:
1372         case INDEX_op_muls2_i32:
1373             op_new = INDEX_op_mul_i32;
1374             goto do_mul2;
1375         case INDEX_op_mulu2_i64:
1376         case INDEX_op_muls2_i64:
1377             op_new = INDEX_op_mul_i64;
1378         do_mul2:
1379             args -= 4;
1380             nb_iargs = 2;
1381             nb_oargs = 2;
1382             /* Likewise, test for the high part of the operation dead.  */
1383             if (dead_temps[args[1]] && !mem_temps[args[1]]) {
1384                 if (dead_temps[args[0]] && !mem_temps[args[0]]) {
1385                     goto do_remove;
1386                 }
1387                 s->gen_opc_buf[op_index] = op = op_new;
1388                 args[1] = args[2];
1389                 args[2] = args[3];
1390                 assert(s->gen_opc_buf[op_index + 1] == INDEX_op_nop);
1391                 tcg_set_nop(s, s->gen_opc_buf + op_index + 1, args + 3, 1);
1392                 /* Fall through and mark the single-word operation live.  */
1393                 nb_oargs = 1;
1394             }
1395             goto do_not_remove;
1396 
1397         default:
1398             /* XXX: optimize by hardcoding common cases (e.g. triadic ops) */
1399             args -= def->nb_args;
1400             nb_iargs = def->nb_iargs;
1401             nb_oargs = def->nb_oargs;
1402 
1403             /* Test if the operation can be removed because all
1404                its outputs are dead. We assume that nb_oargs == 0
1405                implies side effects */
1406             if (!(def->flags & TCG_OPF_SIDE_EFFECTS) && nb_oargs != 0) {
1407                 for(i = 0; i < nb_oargs; i++) {
1408                     arg = args[i];
1409                     if (!dead_temps[arg] || mem_temps[arg]) {
1410                         goto do_not_remove;
1411                     }
1412                 }
1413             do_remove:
1414                 tcg_set_nop(s, s->gen_opc_buf + op_index, args, def->nb_args);
1415 #ifdef CONFIG_PROFILER
1416                 s->del_op_count++;
1417 #endif
1418             } else {
1419             do_not_remove:
1420 
1421                 /* output args are dead */
1422                 dead_args = 0;
1423                 sync_args = 0;
1424                 for(i = 0; i < nb_oargs; i++) {
1425                     arg = args[i];
1426                     if (dead_temps[arg]) {
1427                         dead_args |= (1 << i);
1428                     }
1429                     if (mem_temps[arg]) {
1430                         sync_args |= (1 << i);
1431                     }
1432                     dead_temps[arg] = 1;
1433                     mem_temps[arg] = 0;
1434                 }
1435 
1436                 /* if end of basic block, update */
1437                 if (def->flags & TCG_OPF_BB_END) {
1438                     tcg_la_bb_end(s, dead_temps, mem_temps);
1439                 } else if (def->flags & TCG_OPF_SIDE_EFFECTS) {
1440                     /* globals should be synced to memory */
1441                     memset(mem_temps, 1, s->nb_globals);
1442                 }
1443 
1444                 /* input args are live */
1445                 for(i = nb_oargs; i < nb_oargs + nb_iargs; i++) {
1446                     arg = args[i];
1447                     if (dead_temps[arg]) {
1448                         dead_args |= (1 << i);
1449                     }
1450                     dead_temps[arg] = 0;
1451                 }
1452                 s->op_dead_args[op_index] = dead_args;
1453                 s->op_sync_args[op_index] = sync_args;
1454             }
1455             break;
1456         }
1457         op_index--;
1458     }
1459 
1460     if (args != s->gen_opparam_buf) {
1461         tcg_abort();
1462     }
1463 }
1464 #else
1465 /* dummy liveness analysis */
1466 static void tcg_liveness_analysis(TCGContext *s)
1467 {
1468     int nb_ops;
1469     nb_ops = s->gen_opc_ptr - s->gen_opc_buf;
1470 
1471     s->op_dead_args = tcg_malloc(nb_ops * sizeof(uint16_t));
1472     memset(s->op_dead_args, 0, nb_ops * sizeof(uint16_t));
1473     s->op_sync_args = tcg_malloc(nb_ops * sizeof(uint8_t));
1474     memset(s->op_sync_args, 0, nb_ops * sizeof(uint8_t));
1475 }
1476 #endif
1477 
1478 #ifndef NDEBUG
1479 static void dump_regs(TCGContext *s)
1480 {
1481     TCGTemp *ts;
1482     int i;
1483     char buf[64];
1484 
1485     for(i = 0; i < s->nb_temps; i++) {
1486         ts = &s->temps[i];
1487         printf("  %10s: ", tcg_get_arg_str_idx(s, buf, sizeof(buf), i));
1488         switch(ts->val_type) {
1489         case TEMP_VAL_REG:
1490             printf("%s", tcg_target_reg_names[ts->reg]);
1491             break;
1492         case TEMP_VAL_MEM:
1493             printf("%d(%s)", (int)ts->mem_offset, tcg_target_reg_names[ts->mem_reg]);
1494             break;
1495         case TEMP_VAL_CONST:
1496             printf("$0x%" TCG_PRIlx, ts->val);
1497             break;
1498         case TEMP_VAL_DEAD:
1499             printf("D");
1500             break;
1501         default:
1502             printf("???");
1503             break;
1504         }
1505         printf("\n");
1506     }
1507 
1508     for(i = 0; i < TCG_TARGET_NB_REGS; i++) {
1509         if (s->reg_to_temp[i] >= 0) {
1510             printf("%s: %s\n",
1511                    tcg_target_reg_names[i],
1512                    tcg_get_arg_str_idx(s, buf, sizeof(buf), s->reg_to_temp[i]));
1513         }
1514     }
1515 }
1516 
1517 static void check_regs(TCGContext *s)
1518 {
1519     int reg, k;
1520     TCGTemp *ts;
1521     char buf[64];
1522 
1523     for(reg = 0; reg < TCG_TARGET_NB_REGS; reg++) {
1524         k = s->reg_to_temp[reg];
1525         if (k >= 0) {
1526             ts = &s->temps[k];
1527             if (ts->val_type != TEMP_VAL_REG ||
1528                 ts->reg != reg) {
1529                 printf("Inconsistency for register %s:\n",
1530                        tcg_target_reg_names[reg]);
1531                 goto fail;
1532             }
1533         }
1534     }
1535     for(k = 0; k < s->nb_temps; k++) {
1536         ts = &s->temps[k];
1537         if (ts->val_type == TEMP_VAL_REG &&
1538             !ts->fixed_reg &&
1539             s->reg_to_temp[ts->reg] != k) {
1540                 printf("Inconsistency for temp %s:\n",
1541                        tcg_get_arg_str_idx(s, buf, sizeof(buf), k));
1542         fail:
1543                 printf("reg state:\n");
1544                 dump_regs(s);
1545                 tcg_abort();
1546         }
1547     }
1548 }
1549 #endif
1550 
1551 static void temp_allocate_frame(TCGContext *s, int temp)
1552 {
1553     TCGTemp *ts;
1554     ts = &s->temps[temp];
1555 #if !(defined(__sparc__) && TCG_TARGET_REG_BITS == 64)
1556     /* Sparc64 stack is accessed with offset of 2047 */
1557     s->current_frame_offset = (s->current_frame_offset +
1558                                (tcg_target_long)sizeof(tcg_target_long) - 1) &
1559         ~(sizeof(tcg_target_long) - 1);
1560 #endif
1561     if (s->current_frame_offset + (tcg_target_long)sizeof(tcg_target_long) >
1562         s->frame_end) {
1563         tcg_abort();
1564     }
1565     ts->mem_offset = s->current_frame_offset;
1566     ts->mem_reg = s->frame_reg;
1567     ts->mem_allocated = 1;
1568     s->current_frame_offset += (tcg_target_long)sizeof(tcg_target_long);
1569 }
1570 
1571 /* sync register 'reg' by saving it to the corresponding temporary */
1572 static inline void tcg_reg_sync(TCGContext *s, int reg)
1573 {
1574     TCGTemp *ts;
1575     int temp;
1576 
1577     temp = s->reg_to_temp[reg];
1578     ts = &s->temps[temp];
1579     assert(ts->val_type == TEMP_VAL_REG);
1580     if (!ts->mem_coherent && !ts->fixed_reg) {
1581         if (!ts->mem_allocated) {
1582             temp_allocate_frame(s, temp);
1583         }
1584         tcg_out_st(s, ts->type, reg, ts->mem_reg, ts->mem_offset);
1585     }
1586     ts->mem_coherent = 1;
1587 }
1588 
1589 /* free register 'reg' by spilling the corresponding temporary if necessary */
1590 static void tcg_reg_free(TCGContext *s, int reg)
1591 {
1592     int temp;
1593 
1594     temp = s->reg_to_temp[reg];
1595     if (temp != -1) {
1596         tcg_reg_sync(s, reg);
1597         s->temps[temp].val_type = TEMP_VAL_MEM;
1598         s->reg_to_temp[reg] = -1;
1599     }
1600 }
1601 
1602 /* Allocate a register belonging to reg1 & ~reg2 */
1603 static int tcg_reg_alloc(TCGContext *s, TCGRegSet reg1, TCGRegSet reg2)
1604 {
1605     int i, reg;
1606     TCGRegSet reg_ct;
1607 
1608     tcg_regset_andnot(reg_ct, reg1, reg2);
1609 
1610     /* first try free registers */
1611     for(i = 0; i < ARRAY_SIZE(tcg_target_reg_alloc_order); i++) {
1612         reg = tcg_target_reg_alloc_order[i];
1613         if (tcg_regset_test_reg(reg_ct, reg) && s->reg_to_temp[reg] == -1)
1614             return reg;
1615     }
1616 
1617     /* XXX: do better spill choice */
1618     for(i = 0; i < ARRAY_SIZE(tcg_target_reg_alloc_order); i++) {
1619         reg = tcg_target_reg_alloc_order[i];
1620         if (tcg_regset_test_reg(reg_ct, reg)) {
1621             tcg_reg_free(s, reg);
1622             return reg;
1623         }
1624     }
1625 
1626     tcg_abort();
1627 }
1628 
1629 /* mark a temporary as dead. */
1630 static inline void temp_dead(TCGContext *s, int temp)
1631 {
1632     TCGTemp *ts;
1633 
1634     ts = &s->temps[temp];
1635     if (!ts->fixed_reg) {
1636         if (ts->val_type == TEMP_VAL_REG) {
1637             s->reg_to_temp[ts->reg] = -1;
1638         }
1639         if (temp < s->nb_globals || ts->temp_local) {
1640             ts->val_type = TEMP_VAL_MEM;
1641         } else {
1642             ts->val_type = TEMP_VAL_DEAD;
1643         }
1644     }
1645 }
1646 
1647 /* sync a temporary to memory. 'allocated_regs' is used in case a
1648    temporary registers needs to be allocated to store a constant. */
1649 static inline void temp_sync(TCGContext *s, int temp, TCGRegSet allocated_regs)
1650 {
1651     TCGTemp *ts;
1652 
1653     ts = &s->temps[temp];
1654     if (!ts->fixed_reg) {
1655         switch(ts->val_type) {
1656         case TEMP_VAL_CONST:
1657             ts->reg = tcg_reg_alloc(s, tcg_target_available_regs[ts->type],
1658                                     allocated_regs);
1659             ts->val_type = TEMP_VAL_REG;
1660             s->reg_to_temp[ts->reg] = temp;
1661             ts->mem_coherent = 0;
1662             tcg_out_movi(s, ts->type, ts->reg, ts->val);
1663             /* fallthrough*/
1664         case TEMP_VAL_REG:
1665             tcg_reg_sync(s, ts->reg);
1666             break;
1667         case TEMP_VAL_DEAD:
1668         case TEMP_VAL_MEM:
1669             break;
1670         default:
1671             tcg_abort();
1672         }
1673     }
1674 }
1675 
1676 /* save a temporary to memory. 'allocated_regs' is used in case a
1677    temporary registers needs to be allocated to store a constant. */
1678 static inline void temp_save(TCGContext *s, int temp, TCGRegSet allocated_regs)
1679 {
1680 #ifdef USE_LIVENESS_ANALYSIS
1681     /* The liveness analysis already ensures that globals are back
1682        in memory. Keep an assert for safety. */
1683     assert(s->temps[temp].val_type == TEMP_VAL_MEM || s->temps[temp].fixed_reg);
1684 #else
1685     temp_sync(s, temp, allocated_regs);
1686     temp_dead(s, temp);
1687 #endif
1688 }
1689 
1690 /* save globals to their canonical location and assume they can be
1691    modified be the following code. 'allocated_regs' is used in case a
1692    temporary registers needs to be allocated to store a constant. */
1693 static void save_globals(TCGContext *s, TCGRegSet allocated_regs)
1694 {
1695     int i;
1696 
1697     for(i = 0; i < s->nb_globals; i++) {
1698         temp_save(s, i, allocated_regs);
1699     }
1700 }
1701 
1702 /* sync globals to their canonical location and assume they can be
1703    read by the following code. 'allocated_regs' is used in case a
1704    temporary registers needs to be allocated to store a constant. */
1705 static void sync_globals(TCGContext *s, TCGRegSet allocated_regs)
1706 {
1707     int i;
1708 
1709     for (i = 0; i < s->nb_globals; i++) {
1710 #ifdef USE_LIVENESS_ANALYSIS
1711         assert(s->temps[i].val_type != TEMP_VAL_REG || s->temps[i].fixed_reg ||
1712                s->temps[i].mem_coherent);
1713 #else
1714         temp_sync(s, i, allocated_regs);
1715 #endif
1716     }
1717 }
1718 
1719 /* at the end of a basic block, we assume all temporaries are dead and
1720    all globals are stored at their canonical location. */
1721 static void tcg_reg_alloc_bb_end(TCGContext *s, TCGRegSet allocated_regs)
1722 {
1723     TCGTemp *ts;
1724     int i;
1725 
1726     for(i = s->nb_globals; i < s->nb_temps; i++) {
1727         ts = &s->temps[i];
1728         if (ts->temp_local) {
1729             temp_save(s, i, allocated_regs);
1730         } else {
1731 #ifdef USE_LIVENESS_ANALYSIS
1732             /* The liveness analysis already ensures that temps are dead.
1733                Keep an assert for safety. */
1734             assert(ts->val_type == TEMP_VAL_DEAD);
1735 #else
1736             temp_dead(s, i);
1737 #endif
1738         }
1739     }
1740 
1741     save_globals(s, allocated_regs);
1742 }
1743 
1744 #define IS_DEAD_ARG(n) ((dead_args >> (n)) & 1)
1745 #define NEED_SYNC_ARG(n) ((sync_args >> (n)) & 1)
1746 
1747 static void tcg_reg_alloc_movi(TCGContext *s, const TCGArg *args,
1748                                uint16_t dead_args, uint8_t sync_args)
1749 {
1750     TCGTemp *ots;
1751     tcg_target_ulong val;
1752 
1753     ots = &s->temps[args[0]];
1754     val = args[1];
1755 
1756     if (ots->fixed_reg) {
1757         /* for fixed registers, we do not do any constant
1758            propagation */
1759         tcg_out_movi(s, ots->type, ots->reg, val);
1760     } else {
1761         /* The movi is not explicitly generated here */
1762         if (ots->val_type == TEMP_VAL_REG)
1763             s->reg_to_temp[ots->reg] = -1;
1764         ots->val_type = TEMP_VAL_CONST;
1765         ots->val = val;
1766     }
1767     if (NEED_SYNC_ARG(0)) {
1768         temp_sync(s, args[0], s->reserved_regs);
1769     }
1770     if (IS_DEAD_ARG(0)) {
1771         temp_dead(s, args[0]);
1772     }
1773 }
1774 
1775 static void tcg_reg_alloc_mov(TCGContext *s, const TCGOpDef *def,
1776                               const TCGArg *args, uint16_t dead_args,
1777                               uint8_t sync_args)
1778 {
1779     TCGRegSet allocated_regs;
1780     TCGTemp *ts, *ots;
1781     const TCGArgConstraint *arg_ct, *oarg_ct;
1782 
1783     tcg_regset_set(allocated_regs, s->reserved_regs);
1784     ots = &s->temps[args[0]];
1785     ts = &s->temps[args[1]];
1786     oarg_ct = &def->args_ct[0];
1787     arg_ct = &def->args_ct[1];
1788 
1789     /* If the source value is not in a register, and we're going to be
1790        forced to have it in a register in order to perform the copy,
1791        then copy the SOURCE value into its own register first.  That way
1792        we don't have to reload SOURCE the next time it is used. */
1793     if (((NEED_SYNC_ARG(0) || ots->fixed_reg) && ts->val_type != TEMP_VAL_REG)
1794         || ts->val_type == TEMP_VAL_MEM) {
1795         ts->reg = tcg_reg_alloc(s, arg_ct->u.regs, allocated_regs);
1796         if (ts->val_type == TEMP_VAL_MEM) {
1797             tcg_out_ld(s, ts->type, ts->reg, ts->mem_reg, ts->mem_offset);
1798             ts->mem_coherent = 1;
1799         } else if (ts->val_type == TEMP_VAL_CONST) {
1800             tcg_out_movi(s, ts->type, ts->reg, ts->val);
1801         }
1802         s->reg_to_temp[ts->reg] = args[1];
1803         ts->val_type = TEMP_VAL_REG;
1804     }
1805 
1806     if (IS_DEAD_ARG(0) && !ots->fixed_reg) {
1807         /* mov to a non-saved dead register makes no sense (even with
1808            liveness analysis disabled). */
1809         assert(NEED_SYNC_ARG(0));
1810         /* The code above should have moved the temp to a register. */
1811         assert(ts->val_type == TEMP_VAL_REG);
1812         if (!ots->mem_allocated) {
1813             temp_allocate_frame(s, args[0]);
1814         }
1815         tcg_out_st(s, ots->type, ts->reg, ots->mem_reg, ots->mem_offset);
1816         if (IS_DEAD_ARG(1)) {
1817             temp_dead(s, args[1]);
1818         }
1819         temp_dead(s, args[0]);
1820     } else if (ts->val_type == TEMP_VAL_CONST) {
1821         /* propagate constant */
1822         if (ots->val_type == TEMP_VAL_REG) {
1823             s->reg_to_temp[ots->reg] = -1;
1824         }
1825         ots->val_type = TEMP_VAL_CONST;
1826         ots->val = ts->val;
1827     } else {
1828         /* The code in the first if block should have moved the
1829            temp to a register. */
1830         assert(ts->val_type == TEMP_VAL_REG);
1831         if (IS_DEAD_ARG(1) && !ts->fixed_reg && !ots->fixed_reg) {
1832             /* the mov can be suppressed */
1833             if (ots->val_type == TEMP_VAL_REG) {
1834                 s->reg_to_temp[ots->reg] = -1;
1835             }
1836             ots->reg = ts->reg;
1837             temp_dead(s, args[1]);
1838         } else {
1839             if (ots->val_type != TEMP_VAL_REG) {
1840                 /* When allocating a new register, make sure to not spill the
1841                    input one. */
1842                 tcg_regset_set_reg(allocated_regs, ts->reg);
1843                 ots->reg = tcg_reg_alloc(s, oarg_ct->u.regs, allocated_regs);
1844             }
1845             tcg_out_mov(s, ots->type, ots->reg, ts->reg);
1846         }
1847         ots->val_type = TEMP_VAL_REG;
1848         ots->mem_coherent = 0;
1849         s->reg_to_temp[ots->reg] = args[0];
1850         if (NEED_SYNC_ARG(0)) {
1851             tcg_reg_sync(s, ots->reg);
1852         }
1853     }
1854 }
1855 
1856 static void tcg_reg_alloc_op(TCGContext *s,
1857                              const TCGOpDef *def, TCGOpcode opc,
1858                              const TCGArg *args, uint16_t dead_args,
1859                              uint8_t sync_args)
1860 {
1861     TCGRegSet allocated_regs;
1862     int i, k, nb_iargs, nb_oargs, reg;
1863     TCGArg arg;
1864     const TCGArgConstraint *arg_ct;
1865     TCGTemp *ts;
1866     TCGArg new_args[TCG_MAX_OP_ARGS];
1867     int const_args[TCG_MAX_OP_ARGS];
1868 
1869     nb_oargs = def->nb_oargs;
1870     nb_iargs = def->nb_iargs;
1871 
1872     /* copy constants */
1873     memcpy(new_args + nb_oargs + nb_iargs,
1874            args + nb_oargs + nb_iargs,
1875            sizeof(TCGArg) * def->nb_cargs);
1876 
1877     /* satisfy input constraints */
1878     tcg_regset_set(allocated_regs, s->reserved_regs);
1879     for(k = 0; k < nb_iargs; k++) {
1880         i = def->sorted_args[nb_oargs + k];
1881         arg = args[i];
1882         arg_ct = &def->args_ct[i];
1883         ts = &s->temps[arg];
1884         if (ts->val_type == TEMP_VAL_MEM) {
1885             reg = tcg_reg_alloc(s, arg_ct->u.regs, allocated_regs);
1886             tcg_out_ld(s, ts->type, reg, ts->mem_reg, ts->mem_offset);
1887             ts->val_type = TEMP_VAL_REG;
1888             ts->reg = reg;
1889             ts->mem_coherent = 1;
1890             s->reg_to_temp[reg] = arg;
1891         } else if (ts->val_type == TEMP_VAL_CONST) {
1892             if (tcg_target_const_match(ts->val, arg_ct)) {
1893                 /* constant is OK for instruction */
1894                 const_args[i] = 1;
1895                 new_args[i] = ts->val;
1896                 goto iarg_end;
1897             } else {
1898                 /* need to move to a register */
1899                 reg = tcg_reg_alloc(s, arg_ct->u.regs, allocated_regs);
1900                 tcg_out_movi(s, ts->type, reg, ts->val);
1901                 ts->val_type = TEMP_VAL_REG;
1902                 ts->reg = reg;
1903                 ts->mem_coherent = 0;
1904                 s->reg_to_temp[reg] = arg;
1905             }
1906         }
1907         assert(ts->val_type == TEMP_VAL_REG);
1908         if (arg_ct->ct & TCG_CT_IALIAS) {
1909             if (ts->fixed_reg) {
1910                 /* if fixed register, we must allocate a new register
1911                    if the alias is not the same register */
1912                 if (arg != args[arg_ct->alias_index])
1913                     goto allocate_in_reg;
1914             } else {
1915                 /* if the input is aliased to an output and if it is
1916                    not dead after the instruction, we must allocate
1917                    a new register and move it */
1918                 if (!IS_DEAD_ARG(i)) {
1919                     goto allocate_in_reg;
1920                 }
1921             }
1922         }
1923         reg = ts->reg;
1924         if (tcg_regset_test_reg(arg_ct->u.regs, reg)) {
1925             /* nothing to do : the constraint is satisfied */
1926         } else {
1927         allocate_in_reg:
1928             /* allocate a new register matching the constraint
1929                and move the temporary register into it */
1930             reg = tcg_reg_alloc(s, arg_ct->u.regs, allocated_regs);
1931             tcg_out_mov(s, ts->type, reg, ts->reg);
1932         }
1933         new_args[i] = reg;
1934         const_args[i] = 0;
1935         tcg_regset_set_reg(allocated_regs, reg);
1936     iarg_end: ;
1937     }
1938 
1939     /* mark dead temporaries and free the associated registers */
1940     for (i = nb_oargs; i < nb_oargs + nb_iargs; i++) {
1941         if (IS_DEAD_ARG(i)) {
1942             temp_dead(s, args[i]);
1943         }
1944     }
1945 
1946     if (def->flags & TCG_OPF_BB_END) {
1947         tcg_reg_alloc_bb_end(s, allocated_regs);
1948     } else {
1949         if (def->flags & TCG_OPF_CALL_CLOBBER) {
1950             /* XXX: permit generic clobber register list ? */
1951             for(reg = 0; reg < TCG_TARGET_NB_REGS; reg++) {
1952                 if (tcg_regset_test_reg(tcg_target_call_clobber_regs, reg)) {
1953                     tcg_reg_free(s, reg);
1954                 }
1955             }
1956         }
1957         if (def->flags & TCG_OPF_SIDE_EFFECTS) {
1958             /* sync globals if the op has side effects and might trigger
1959                an exception. */
1960             sync_globals(s, allocated_regs);
1961         }
1962 
1963         /* satisfy the output constraints */
1964         tcg_regset_set(allocated_regs, s->reserved_regs);
1965         for(k = 0; k < nb_oargs; k++) {
1966             i = def->sorted_args[k];
1967             arg = args[i];
1968             arg_ct = &def->args_ct[i];
1969             ts = &s->temps[arg];
1970             if (arg_ct->ct & TCG_CT_ALIAS) {
1971                 reg = new_args[arg_ct->alias_index];
1972             } else {
1973                 /* if fixed register, we try to use it */
1974                 reg = ts->reg;
1975                 if (ts->fixed_reg &&
1976                     tcg_regset_test_reg(arg_ct->u.regs, reg)) {
1977                     goto oarg_end;
1978                 }
1979                 reg = tcg_reg_alloc(s, arg_ct->u.regs, allocated_regs);
1980             }
1981             tcg_regset_set_reg(allocated_regs, reg);
1982             /* if a fixed register is used, then a move will be done afterwards */
1983             if (!ts->fixed_reg) {
1984                 if (ts->val_type == TEMP_VAL_REG) {
1985                     s->reg_to_temp[ts->reg] = -1;
1986                 }
1987                 ts->val_type = TEMP_VAL_REG;
1988                 ts->reg = reg;
1989                 /* temp value is modified, so the value kept in memory is
1990                    potentially not the same */
1991                 ts->mem_coherent = 0;
1992                 s->reg_to_temp[reg] = arg;
1993             }
1994         oarg_end:
1995             new_args[i] = reg;
1996         }
1997     }
1998 
1999     /* emit instruction */
2000     tcg_out_op(s, opc, new_args, const_args);
2001 
2002     /* move the outputs in the correct register if needed */
2003     for(i = 0; i < nb_oargs; i++) {
2004         ts = &s->temps[args[i]];
2005         reg = new_args[i];
2006         if (ts->fixed_reg && ts->reg != reg) {
2007             tcg_out_mov(s, ts->type, ts->reg, reg);
2008         }
2009         if (NEED_SYNC_ARG(i)) {
2010             tcg_reg_sync(s, reg);
2011         }
2012         if (IS_DEAD_ARG(i)) {
2013             temp_dead(s, args[i]);
2014         }
2015     }
2016 }
2017 
2018 #ifdef TCG_TARGET_STACK_GROWSUP
2019 #define STACK_DIR(x) (-(x))
2020 #else
2021 #define STACK_DIR(x) (x)
2022 #endif
2023 
2024 static int tcg_reg_alloc_call(TCGContext *s, const TCGOpDef *def,
2025                               TCGOpcode opc, const TCGArg *args,
2026                               uint16_t dead_args, uint8_t sync_args)
2027 {
2028     int nb_iargs, nb_oargs, flags, nb_regs, i, reg, nb_params;
2029     TCGArg arg, func_arg;
2030     TCGTemp *ts;
2031     tcg_target_long stack_offset, call_stack_size, func_addr;
2032     int const_func_arg, allocate_args;
2033     TCGRegSet allocated_regs;
2034     const TCGArgConstraint *arg_ct;
2035 
2036     arg = *args++;
2037 
2038     nb_oargs = arg >> 16;
2039     nb_iargs = arg & 0xffff;
2040     nb_params = nb_iargs - 1;
2041 
2042     flags = args[nb_oargs + nb_iargs];
2043 
2044     nb_regs = ARRAY_SIZE(tcg_target_call_iarg_regs);
2045     if (nb_regs > nb_params)
2046         nb_regs = nb_params;
2047 
2048     /* assign stack slots first */
2049     call_stack_size = (nb_params - nb_regs) * sizeof(tcg_target_long);
2050     call_stack_size = (call_stack_size + TCG_TARGET_STACK_ALIGN - 1) &
2051         ~(TCG_TARGET_STACK_ALIGN - 1);
2052     allocate_args = (call_stack_size > TCG_STATIC_CALL_ARGS_SIZE);
2053     if (allocate_args) {
2054         /* XXX: if more than TCG_STATIC_CALL_ARGS_SIZE is needed,
2055            preallocate call stack */
2056         tcg_abort();
2057     }
2058 
2059     stack_offset = TCG_TARGET_CALL_STACK_OFFSET;
2060     for(i = nb_regs; i < nb_params; i++) {
2061         arg = args[nb_oargs + i];
2062 #ifdef TCG_TARGET_STACK_GROWSUP
2063         stack_offset -= sizeof(tcg_target_long);
2064 #endif
2065         if (arg != TCG_CALL_DUMMY_ARG) {
2066             ts = &s->temps[arg];
2067             if (ts->val_type == TEMP_VAL_REG) {
2068                 tcg_out_st(s, ts->type, ts->reg, TCG_REG_CALL_STACK, stack_offset);
2069             } else if (ts->val_type == TEMP_VAL_MEM) {
2070                 reg = tcg_reg_alloc(s, tcg_target_available_regs[ts->type],
2071                                     s->reserved_regs);
2072                 /* XXX: not correct if reading values from the stack */
2073                 tcg_out_ld(s, ts->type, reg, ts->mem_reg, ts->mem_offset);
2074                 tcg_out_st(s, ts->type, reg, TCG_REG_CALL_STACK, stack_offset);
2075             } else if (ts->val_type == TEMP_VAL_CONST) {
2076                 reg = tcg_reg_alloc(s, tcg_target_available_regs[ts->type],
2077                                     s->reserved_regs);
2078                 /* XXX: sign extend may be needed on some targets */
2079                 tcg_out_movi(s, ts->type, reg, ts->val);
2080                 tcg_out_st(s, ts->type, reg, TCG_REG_CALL_STACK, stack_offset);
2081             } else {
2082                 tcg_abort();
2083             }
2084         }
2085 #ifndef TCG_TARGET_STACK_GROWSUP
2086         stack_offset += sizeof(tcg_target_long);
2087 #endif
2088     }
2089 
2090     /* assign input registers */
2091     tcg_regset_set(allocated_regs, s->reserved_regs);
2092     for(i = 0; i < nb_regs; i++) {
2093         arg = args[nb_oargs + i];
2094         if (arg != TCG_CALL_DUMMY_ARG) {
2095             ts = &s->temps[arg];
2096             reg = tcg_target_call_iarg_regs[i];
2097             tcg_reg_free(s, reg);
2098             if (ts->val_type == TEMP_VAL_REG) {
2099                 if (ts->reg != reg) {
2100                     tcg_out_mov(s, ts->type, reg, ts->reg);
2101                 }
2102             } else if (ts->val_type == TEMP_VAL_MEM) {
2103                 tcg_out_ld(s, ts->type, reg, ts->mem_reg, ts->mem_offset);
2104             } else if (ts->val_type == TEMP_VAL_CONST) {
2105                 /* XXX: sign extend ? */
2106                 tcg_out_movi(s, ts->type, reg, ts->val);
2107             } else {
2108                 tcg_abort();
2109             }
2110             tcg_regset_set_reg(allocated_regs, reg);
2111         }
2112     }
2113 
2114     /* assign function address */
2115     func_arg = args[nb_oargs + nb_iargs - 1];
2116     arg_ct = &def->args_ct[0];
2117     ts = &s->temps[func_arg];
2118     func_addr = ts->val;
2119     const_func_arg = 0;
2120     if (ts->val_type == TEMP_VAL_MEM) {
2121         reg = tcg_reg_alloc(s, arg_ct->u.regs, allocated_regs);
2122         tcg_out_ld(s, ts->type, reg, ts->mem_reg, ts->mem_offset);
2123         func_arg = reg;
2124         tcg_regset_set_reg(allocated_regs, reg);
2125     } else if (ts->val_type == TEMP_VAL_REG) {
2126         reg = ts->reg;
2127         if (!tcg_regset_test_reg(arg_ct->u.regs, reg)) {
2128             reg = tcg_reg_alloc(s, arg_ct->u.regs, allocated_regs);
2129             tcg_out_mov(s, ts->type, reg, ts->reg);
2130         }
2131         func_arg = reg;
2132         tcg_regset_set_reg(allocated_regs, reg);
2133     } else if (ts->val_type == TEMP_VAL_CONST) {
2134         if (tcg_target_const_match(func_addr, arg_ct)) {
2135             const_func_arg = 1;
2136             func_arg = func_addr;
2137         } else {
2138             reg = tcg_reg_alloc(s, arg_ct->u.regs, allocated_regs);
2139             tcg_out_movi(s, ts->type, reg, func_addr);
2140             func_arg = reg;
2141             tcg_regset_set_reg(allocated_regs, reg);
2142         }
2143     } else {
2144         tcg_abort();
2145     }
2146 
2147 
2148     /* mark dead temporaries and free the associated registers */
2149     for(i = nb_oargs; i < nb_iargs + nb_oargs; i++) {
2150         if (IS_DEAD_ARG(i)) {
2151             temp_dead(s, args[i]);
2152         }
2153     }
2154 
2155     /* clobber call registers */
2156     for(reg = 0; reg < TCG_TARGET_NB_REGS; reg++) {
2157         if (tcg_regset_test_reg(tcg_target_call_clobber_regs, reg)) {
2158             tcg_reg_free(s, reg);
2159         }
2160     }
2161 
2162     /* Save globals if they might be written by the helper, sync them if
2163        they might be read. */
2164     if (flags & TCG_CALL_NO_READ_GLOBALS) {
2165         /* Nothing to do */
2166     } else if (flags & TCG_CALL_NO_WRITE_GLOBALS) {
2167         sync_globals(s, allocated_regs);
2168     } else {
2169         save_globals(s, allocated_regs);
2170     }
2171 
2172     tcg_out_op(s, opc, &func_arg, &const_func_arg);
2173 
2174     /* assign output registers and emit moves if needed */
2175     for(i = 0; i < nb_oargs; i++) {
2176         arg = args[i];
2177         ts = &s->temps[arg];
2178         reg = tcg_target_call_oarg_regs[i];
2179         assert(s->reg_to_temp[reg] == -1);
2180         if (ts->fixed_reg) {
2181             if (ts->reg != reg) {
2182                 tcg_out_mov(s, ts->type, ts->reg, reg);
2183             }
2184         } else {
2185             if (ts->val_type == TEMP_VAL_REG) {
2186                 s->reg_to_temp[ts->reg] = -1;
2187             }
2188             ts->val_type = TEMP_VAL_REG;
2189             ts->reg = reg;
2190             ts->mem_coherent = 0;
2191             s->reg_to_temp[reg] = arg;
2192             if (NEED_SYNC_ARG(i)) {
2193                 tcg_reg_sync(s, reg);
2194             }
2195             if (IS_DEAD_ARG(i)) {
2196                 temp_dead(s, args[i]);
2197             }
2198         }
2199     }
2200 
2201     return nb_iargs + nb_oargs + def->nb_cargs + 1;
2202 }
2203 
2204 #ifdef CONFIG_PROFILER
2205 
2206 static int64_t tcg_table_op_count[NB_OPS];
2207 
2208 static void dump_op_count(void)
2209 {
2210     int i;
2211     FILE *f;
2212     f = fopen("/tmp/op.log", "w");
2213     for(i = INDEX_op_end; i < NB_OPS; i++) {
2214         fprintf(f, "%s %" PRId64 "\n", tcg_op_defs[i].name, tcg_table_op_count[i]);
2215     }
2216     fclose(f);
2217 }
2218 #endif
2219 
2220 
2221 static inline int tcg_gen_code_common(TCGContext *s, uint8_t *gen_code_buf,
2222                                       long search_pc)
2223 {
2224     TCGOpcode opc;
2225     int op_index;
2226     const TCGOpDef *def;
2227     const TCGArg *args;
2228 
2229 #ifdef DEBUG_DISAS
2230     if (unlikely(qemu_loglevel_mask(CPU_LOG_TB_OP))) {
2231         qemu_log("OP:\n");
2232         tcg_dump_ops(s);
2233         qemu_log("\n");
2234     }
2235 #endif
2236 
2237 #ifdef CONFIG_PROFILER
2238     s->opt_time -= profile_getclock();
2239 #endif
2240 
2241 #ifdef USE_TCG_OPTIMIZATIONS
2242     s->gen_opparam_ptr =
2243         tcg_optimize(s, s->gen_opc_ptr, s->gen_opparam_buf, tcg_op_defs);
2244 #endif
2245 
2246 #ifdef CONFIG_PROFILER
2247     s->opt_time += profile_getclock();
2248     s->la_time -= profile_getclock();
2249 #endif
2250 
2251     tcg_liveness_analysis(s);
2252 
2253 #ifdef CONFIG_PROFILER
2254     s->la_time += profile_getclock();
2255 #endif
2256 
2257 #ifdef DEBUG_DISAS
2258     if (unlikely(qemu_loglevel_mask(CPU_LOG_TB_OP_OPT))) {
2259         qemu_log("OP after optimization and liveness analysis:\n");
2260         tcg_dump_ops(s);
2261         qemu_log("\n");
2262     }
2263 #endif
2264 
2265     tcg_reg_alloc_start(s);
2266 
2267     s->code_buf = gen_code_buf;
2268     s->code_ptr = gen_code_buf;
2269 
2270     args = s->gen_opparam_buf;
2271     op_index = 0;
2272 
2273     for(;;) {
2274         opc = s->gen_opc_buf[op_index];
2275 #ifdef CONFIG_PROFILER
2276         tcg_table_op_count[opc]++;
2277 #endif
2278         def = &tcg_op_defs[opc];
2279 #if 0
2280         printf("%s: %d %d %d\n", def->name,
2281                def->nb_oargs, def->nb_iargs, def->nb_cargs);
2282         //        dump_regs(s);
2283 #endif
2284         switch(opc) {
2285         case INDEX_op_mov_i32:
2286         case INDEX_op_mov_i64:
2287             tcg_reg_alloc_mov(s, def, args, s->op_dead_args[op_index],
2288                               s->op_sync_args[op_index]);
2289             break;
2290         case INDEX_op_movi_i32:
2291         case INDEX_op_movi_i64:
2292             tcg_reg_alloc_movi(s, args, s->op_dead_args[op_index],
2293                                s->op_sync_args[op_index]);
2294             break;
2295         case INDEX_op_debug_insn_start:
2296             /* debug instruction */
2297             break;
2298         case INDEX_op_nop:
2299         case INDEX_op_nop1:
2300         case INDEX_op_nop2:
2301         case INDEX_op_nop3:
2302             break;
2303         case INDEX_op_nopn:
2304             args += args[0];
2305             goto next;
2306         case INDEX_op_discard:
2307             temp_dead(s, args[0]);
2308             break;
2309         case INDEX_op_set_label:
2310             tcg_reg_alloc_bb_end(s, s->reserved_regs);
2311             tcg_out_label(s, args[0], s->code_ptr);
2312             break;
2313         case INDEX_op_call:
2314             args += tcg_reg_alloc_call(s, def, opc, args,
2315                                        s->op_dead_args[op_index],
2316                                        s->op_sync_args[op_index]);
2317             goto next;
2318         case INDEX_op_end:
2319             goto the_end;
2320         default:
2321             /* Sanity check that we've not introduced any unhandled opcodes. */
2322             if (def->flags & TCG_OPF_NOT_PRESENT) {
2323                 tcg_abort();
2324             }
2325             /* Note: in order to speed up the code, it would be much
2326                faster to have specialized register allocator functions for
2327                some common argument patterns */
2328             tcg_reg_alloc_op(s, def, opc, args, s->op_dead_args[op_index],
2329                              s->op_sync_args[op_index]);
2330             break;
2331         }
2332         args += def->nb_args;
2333     next:
2334         if (search_pc >= 0 && search_pc < s->code_ptr - gen_code_buf) {
2335             return op_index;
2336         }
2337         op_index++;
2338 #ifndef NDEBUG
2339         check_regs(s);
2340 #endif
2341     }
2342  the_end:
2343 #if defined(CONFIG_QEMU_LDST_OPTIMIZATION) && defined(CONFIG_SOFTMMU)
2344     /* Generate TB finalization at the end of block */
2345     tcg_out_tb_finalize(s);
2346 #endif
2347     return -1;
2348 }
2349 
2350 int tcg_gen_code(TCGContext *s, uint8_t *gen_code_buf)
2351 {
2352 #ifdef CONFIG_PROFILER
2353     {
2354         int n;
2355         n = (s->gen_opc_ptr - s->gen_opc_buf);
2356         s->op_count += n;
2357         if (n > s->op_count_max)
2358             s->op_count_max = n;
2359 
2360         s->temp_count += s->nb_temps;
2361         if (s->nb_temps > s->temp_count_max)
2362             s->temp_count_max = s->nb_temps;
2363     }
2364 #endif
2365 
2366     tcg_gen_code_common(s, gen_code_buf, -1);
2367 
2368     /* flush instruction cache */
2369     flush_icache_range((tcg_target_ulong)gen_code_buf,
2370                        (tcg_target_ulong)s->code_ptr);
2371 
2372     return s->code_ptr -  gen_code_buf;
2373 }
2374 
2375 /* Return the index of the micro operation such as the pc after is <
2376    offset bytes from the start of the TB.  The contents of gen_code_buf must
2377    not be changed, though writing the same values is ok.
2378    Return -1 if not found. */
2379 int tcg_gen_code_search_pc(TCGContext *s, uint8_t *gen_code_buf, long offset)
2380 {
2381     return tcg_gen_code_common(s, gen_code_buf, offset);
2382 }
2383 
2384 #ifdef CONFIG_PROFILER
2385 void tcg_dump_info(FILE *f, fprintf_function cpu_fprintf)
2386 {
2387     TCGContext *s = &tcg_ctx;
2388     int64_t tot;
2389 
2390     tot = s->interm_time + s->code_time;
2391     cpu_fprintf(f, "JIT cycles          %" PRId64 " (%0.3f s at 2.4 GHz)\n",
2392                 tot, tot / 2.4e9);
2393     cpu_fprintf(f, "translated TBs      %" PRId64 " (aborted=%" PRId64 " %0.1f%%)\n",
2394                 s->tb_count,
2395                 s->tb_count1 - s->tb_count,
2396                 s->tb_count1 ? (double)(s->tb_count1 - s->tb_count) / s->tb_count1 * 100.0 : 0);
2397     cpu_fprintf(f, "avg ops/TB          %0.1f max=%d\n",
2398                 s->tb_count ? (double)s->op_count / s->tb_count : 0, s->op_count_max);
2399     cpu_fprintf(f, "deleted ops/TB      %0.2f\n",
2400                 s->tb_count ?
2401                 (double)s->del_op_count / s->tb_count : 0);
2402     cpu_fprintf(f, "avg temps/TB        %0.2f max=%d\n",
2403                 s->tb_count ?
2404                 (double)s->temp_count / s->tb_count : 0,
2405                 s->temp_count_max);
2406 
2407     cpu_fprintf(f, "cycles/op           %0.1f\n",
2408                 s->op_count ? (double)tot / s->op_count : 0);
2409     cpu_fprintf(f, "cycles/in byte      %0.1f\n",
2410                 s->code_in_len ? (double)tot / s->code_in_len : 0);
2411     cpu_fprintf(f, "cycles/out byte     %0.1f\n",
2412                 s->code_out_len ? (double)tot / s->code_out_len : 0);
2413     if (tot == 0)
2414         tot = 1;
2415     cpu_fprintf(f, "  gen_interm time   %0.1f%%\n",
2416                 (double)s->interm_time / tot * 100.0);
2417     cpu_fprintf(f, "  gen_code time     %0.1f%%\n",
2418                 (double)s->code_time / tot * 100.0);
2419     cpu_fprintf(f, "optim./code time    %0.1f%%\n",
2420                 (double)s->opt_time / (s->code_time ? s->code_time : 1)
2421                 * 100.0);
2422     cpu_fprintf(f, "liveness/code time  %0.1f%%\n",
2423                 (double)s->la_time / (s->code_time ? s->code_time : 1) * 100.0);
2424     cpu_fprintf(f, "cpu_restore count   %" PRId64 "\n",
2425                 s->restore_count);
2426     cpu_fprintf(f, "  avg cycles        %0.1f\n",
2427                 s->restore_count ? (double)s->restore_time / s->restore_count : 0);
2428 
2429     dump_op_count();
2430 }
2431 #else
2432 void tcg_dump_info(FILE *f, fprintf_function cpu_fprintf)
2433 {
2434     cpu_fprintf(f, "[TCG profiler not compiled]\n");
2435 }
2436 #endif
2437 
2438 #ifdef ELF_HOST_MACHINE
2439 /* In order to use this feature, the backend needs to do three things:
2440 
2441    (1) Define ELF_HOST_MACHINE to indicate both what value to
2442        put into the ELF image and to indicate support for the feature.
2443 
2444    (2) Define tcg_register_jit.  This should create a buffer containing
2445        the contents of a .debug_frame section that describes the post-
2446        prologue unwind info for the tcg machine.
2447 
2448    (3) Call tcg_register_jit_int, with the constructed .debug_frame.
2449 */
2450 
2451 /* Begin GDB interface.  THE FOLLOWING MUST MATCH GDB DOCS.  */
2452 typedef enum {
2453     JIT_NOACTION = 0,
2454     JIT_REGISTER_FN,
2455     JIT_UNREGISTER_FN
2456 } jit_actions_t;
2457 
2458 struct jit_code_entry {
2459     struct jit_code_entry *next_entry;
2460     struct jit_code_entry *prev_entry;
2461     const void *symfile_addr;
2462     uint64_t symfile_size;
2463 };
2464 
2465 struct jit_descriptor {
2466     uint32_t version;
2467     uint32_t action_flag;
2468     struct jit_code_entry *relevant_entry;
2469     struct jit_code_entry *first_entry;
2470 };
2471 
2472 void __jit_debug_register_code(void) __attribute__((noinline));
2473 void __jit_debug_register_code(void)
2474 {
2475     asm("");
2476 }
2477 
2478 /* Must statically initialize the version, because GDB may check
2479    the version before we can set it.  */
2480 struct jit_descriptor __jit_debug_descriptor = { 1, 0, 0, 0 };
2481 
2482 /* End GDB interface.  */
2483 
2484 static int find_string(const char *strtab, const char *str)
2485 {
2486     const char *p = strtab + 1;
2487 
2488     while (1) {
2489         if (strcmp(p, str) == 0) {
2490             return p - strtab;
2491         }
2492         p += strlen(p) + 1;
2493     }
2494 }
2495 
2496 static void tcg_register_jit_int(void *buf_ptr, size_t buf_size,
2497                                  void *debug_frame, size_t debug_frame_size)
2498 {
2499     struct __attribute__((packed)) DebugInfo {
2500         uint32_t  len;
2501         uint16_t  version;
2502         uint32_t  abbrev;
2503         uint8_t   ptr_size;
2504         uint8_t   cu_die;
2505         uint16_t  cu_lang;
2506         uintptr_t cu_low_pc;
2507         uintptr_t cu_high_pc;
2508         uint8_t   fn_die;
2509         char      fn_name[16];
2510         uintptr_t fn_low_pc;
2511         uintptr_t fn_high_pc;
2512         uint8_t   cu_eoc;
2513     };
2514 
2515     struct ElfImage {
2516         ElfW(Ehdr) ehdr;
2517         ElfW(Phdr) phdr;
2518         ElfW(Shdr) shdr[7];
2519         ElfW(Sym)  sym[2];
2520         struct DebugInfo di;
2521         uint8_t    da[24];
2522         char       str[80];
2523     };
2524 
2525     struct ElfImage *img;
2526 
2527     static const struct ElfImage img_template = {
2528         .ehdr = {
2529             .e_ident[EI_MAG0] = ELFMAG0,
2530             .e_ident[EI_MAG1] = ELFMAG1,
2531             .e_ident[EI_MAG2] = ELFMAG2,
2532             .e_ident[EI_MAG3] = ELFMAG3,
2533             .e_ident[EI_CLASS] = ELF_CLASS,
2534             .e_ident[EI_DATA] = ELF_DATA,
2535             .e_ident[EI_VERSION] = EV_CURRENT,
2536             .e_type = ET_EXEC,
2537             .e_machine = ELF_HOST_MACHINE,
2538             .e_version = EV_CURRENT,
2539             .e_phoff = offsetof(struct ElfImage, phdr),
2540             .e_shoff = offsetof(struct ElfImage, shdr),
2541             .e_ehsize = sizeof(ElfW(Shdr)),
2542             .e_phentsize = sizeof(ElfW(Phdr)),
2543             .e_phnum = 1,
2544             .e_shentsize = sizeof(ElfW(Shdr)),
2545             .e_shnum = ARRAY_SIZE(img->shdr),
2546             .e_shstrndx = ARRAY_SIZE(img->shdr) - 1,
2547 #ifdef ELF_HOST_FLAGS
2548             .e_flags = ELF_HOST_FLAGS,
2549 #endif
2550 #ifdef ELF_OSABI
2551             .e_ident[EI_OSABI] = ELF_OSABI,
2552 #endif
2553         },
2554         .phdr = {
2555             .p_type = PT_LOAD,
2556             .p_flags = PF_X,
2557         },
2558         .shdr = {
2559             [0] = { .sh_type = SHT_NULL },
2560             /* Trick: The contents of code_gen_buffer are not present in
2561                this fake ELF file; that got allocated elsewhere.  Therefore
2562                we mark .text as SHT_NOBITS (similar to .bss) so that readers
2563                will not look for contents.  We can record any address.  */
2564             [1] = { /* .text */
2565                 .sh_type = SHT_NOBITS,
2566                 .sh_flags = SHF_EXECINSTR | SHF_ALLOC,
2567             },
2568             [2] = { /* .debug_info */
2569                 .sh_type = SHT_PROGBITS,
2570                 .sh_offset = offsetof(struct ElfImage, di),
2571                 .sh_size = sizeof(struct DebugInfo),
2572             },
2573             [3] = { /* .debug_abbrev */
2574                 .sh_type = SHT_PROGBITS,
2575                 .sh_offset = offsetof(struct ElfImage, da),
2576                 .sh_size = sizeof(img->da),
2577             },
2578             [4] = { /* .debug_frame */
2579                 .sh_type = SHT_PROGBITS,
2580                 .sh_offset = sizeof(struct ElfImage),
2581             },
2582             [5] = { /* .symtab */
2583                 .sh_type = SHT_SYMTAB,
2584                 .sh_offset = offsetof(struct ElfImage, sym),
2585                 .sh_size = sizeof(img->sym),
2586                 .sh_info = 1,
2587                 .sh_link = ARRAY_SIZE(img->shdr) - 1,
2588                 .sh_entsize = sizeof(ElfW(Sym)),
2589             },
2590             [6] = { /* .strtab */
2591                 .sh_type = SHT_STRTAB,
2592                 .sh_offset = offsetof(struct ElfImage, str),
2593                 .sh_size = sizeof(img->str),
2594             }
2595         },
2596         .sym = {
2597             [1] = { /* code_gen_buffer */
2598                 .st_info = ELF_ST_INFO(STB_GLOBAL, STT_FUNC),
2599                 .st_shndx = 1,
2600             }
2601         },
2602         .di = {
2603             .len = sizeof(struct DebugInfo) - 4,
2604             .version = 2,
2605             .ptr_size = sizeof(void *),
2606             .cu_die = 1,
2607             .cu_lang = 0x8001,  /* DW_LANG_Mips_Assembler */
2608             .fn_die = 2,
2609             .fn_name = "code_gen_buffer"
2610         },
2611         .da = {
2612             1,          /* abbrev number (the cu) */
2613             0x11, 1,    /* DW_TAG_compile_unit, has children */
2614             0x13, 0x5,  /* DW_AT_language, DW_FORM_data2 */
2615             0x11, 0x1,  /* DW_AT_low_pc, DW_FORM_addr */
2616             0x12, 0x1,  /* DW_AT_high_pc, DW_FORM_addr */
2617             0, 0,       /* end of abbrev */
2618             2,          /* abbrev number (the fn) */
2619             0x2e, 0,    /* DW_TAG_subprogram, no children */
2620             0x3, 0x8,   /* DW_AT_name, DW_FORM_string */
2621             0x11, 0x1,  /* DW_AT_low_pc, DW_FORM_addr */
2622             0x12, 0x1,  /* DW_AT_high_pc, DW_FORM_addr */
2623             0, 0,       /* end of abbrev */
2624             0           /* no more abbrev */
2625         },
2626         .str = "\0" ".text\0" ".debug_info\0" ".debug_abbrev\0"
2627                ".debug_frame\0" ".symtab\0" ".strtab\0" "code_gen_buffer",
2628     };
2629 
2630     /* We only need a single jit entry; statically allocate it.  */
2631     static struct jit_code_entry one_entry;
2632 
2633     uintptr_t buf = (uintptr_t)buf_ptr;
2634     size_t img_size = sizeof(struct ElfImage) + debug_frame_size;
2635 
2636     img = g_malloc(img_size);
2637     *img = img_template;
2638     memcpy(img + 1, debug_frame, debug_frame_size);
2639 
2640     img->phdr.p_vaddr = buf;
2641     img->phdr.p_paddr = buf;
2642     img->phdr.p_memsz = buf_size;
2643 
2644     img->shdr[1].sh_name = find_string(img->str, ".text");
2645     img->shdr[1].sh_addr = buf;
2646     img->shdr[1].sh_size = buf_size;
2647 
2648     img->shdr[2].sh_name = find_string(img->str, ".debug_info");
2649     img->shdr[3].sh_name = find_string(img->str, ".debug_abbrev");
2650 
2651     img->shdr[4].sh_name = find_string(img->str, ".debug_frame");
2652     img->shdr[4].sh_size = debug_frame_size;
2653 
2654     img->shdr[5].sh_name = find_string(img->str, ".symtab");
2655     img->shdr[6].sh_name = find_string(img->str, ".strtab");
2656 
2657     img->sym[1].st_name = find_string(img->str, "code_gen_buffer");
2658     img->sym[1].st_value = buf;
2659     img->sym[1].st_size = buf_size;
2660 
2661     img->di.cu_low_pc = buf;
2662     img->di.cu_high_pc = buf_size;
2663     img->di.fn_low_pc = buf;
2664     img->di.fn_high_pc = buf_size;
2665 
2666 #ifdef DEBUG_JIT
2667     /* Enable this block to be able to debug the ELF image file creation.
2668        One can use readelf, objdump, or other inspection utilities.  */
2669     {
2670         FILE *f = fopen("/tmp/qemu.jit", "w+b");
2671         if (f) {
2672             if (fwrite(img, img_size, 1, f) != img_size) {
2673                 /* Avoid stupid unused return value warning for fwrite.  */
2674             }
2675             fclose(f);
2676         }
2677     }
2678 #endif
2679 
2680     one_entry.symfile_addr = img;
2681     one_entry.symfile_size = img_size;
2682 
2683     __jit_debug_descriptor.action_flag = JIT_REGISTER_FN;
2684     __jit_debug_descriptor.relevant_entry = &one_entry;
2685     __jit_debug_descriptor.first_entry = &one_entry;
2686     __jit_debug_register_code();
2687 }
2688 #else
2689 /* No support for the feature.  Provide the entry point expected by exec.c,
2690    and implement the internal function we declared earlier.  */
2691 
2692 static void tcg_register_jit_int(void *buf, size_t size,
2693                                  void *debug_frame, size_t debug_frame_size)
2694 {
2695 }
2696 
2697 void tcg_register_jit(void *buf, size_t buf_size)
2698 {
2699 }
2700 #endif /* ELF_HOST_MACHINE */
2701