2 ** Client for the GDB JIT API.
3 ** Copyright (C) 2005-2014 Mike Pall. See Copyright Notice in luajit.h
18 #include "lj_strfmt.h"
20 #include "lj_dispatch.h"
22 /* This is not compiled in by default.
23 ** Enable with -DLUAJIT_USE_GDBJIT in the Makefile and recompile everything.
25 #ifdef LUAJIT_USE_GDBJIT
27 /* The GDB JIT API allows JIT compilers to pass debug information about
28 ** JIT-compiled code back to GDB. You need at least GDB 7.0 or higher
29 ** to see it in action.
31 ** This is a passive API, so it works even when not running under GDB
32 ** or when attaching to an already running process. Alas, this implies
33 ** enabling it always has a non-negligible overhead -- do not use in
36 ** The LuaJIT GDB JIT client is rather minimal at the moment. It gives
37 ** each trace a symbol name and adds a source location and frame unwind
38 ** information. Obviously LuaJIT itself and any embedding C application
39 ** should be compiled with debug symbols, too (see the Makefile).
41 ** Traces are named TRACE_1, TRACE_2, ... these correspond to the trace
42 ** numbers from -jv or -jdump. Use "break TRACE_1" or "tbreak TRACE_1" etc.
43 ** to set breakpoints on specific traces (even ahead of their creation).
45 ** The source location for each trace allows listing the corresponding
46 ** source lines with the GDB command "list" (but only if the Lua source
47 ** has been loaded from a file). Currently this is always set to the
48 ** location where the trace has been started.
50 ** Frame unwind information can be inspected with the GDB command
51 ** "info frame". This also allows proper backtraces across JIT-compiled
52 ** code with the GDB command "bt".
54 ** You probably want to add the following settings to a .gdbinit file
55 ** (or add them to ~/.gdbinit):
56 ** set disassembly-flavor intel
57 ** set breakpoint pending on
59 ** Here's a sample GDB session:
60 ** ------------------------------------------------------------------------
64 for inner=1,100 do end
70 [TRACE 2 (1/3) x.lua:1 -> 1]
72 $ gdb --quiet --args luajit x.lua
74 Function "TRACE_1" not defined.
75 Temporary breakpoint 1 (TRACE_1) pending.
77 Starting program: luajit x.lua
79 Temporary breakpoint 1, TRACE_1 () at x.lua:2
80 2 for inner=1,100 do end
83 2 for inner=1,100 do end
86 #0 TRACE_1 () at x.lua:2
87 #1 0x08053690 in lua_pcall [...]
89 #7 0x0806ff90 in main [...]
91 Dump of assembler code for function TRACE_1:
92 0xf7fd9fba <TRACE_1+0>: mov DWORD PTR ds:0xf7e0e2a0,0x1
93 0xf7fd9fc4 <TRACE_1+10>: movsd xmm7,QWORD PTR [edx+0x20]
95 0xf7fd9ff8 <TRACE_1+62>: jmp 0xf7fd2014
96 End of assembler dump.
98 Function "TRACE_2" not defined.
99 Temporary breakpoint 2 (TRACE_2) pending.
103 Temporary breakpoint 2, TRACE_2 () at x.lua:1
106 Stack level 0, frame at 0xffffd7c0:
107 eip = 0xf7fd9f60 in TRACE_2 (x.lua:1); saved eip 0x8053690
108 called by frame at 0xffffd7e0
109 source language unknown.
110 Arglist at 0xffffd78c, args:
111 Locals at 0xffffd78c, Previous frame's sp is 0xffffd7c0
113 ebx at 0xffffd7ac, ebp at 0xffffd7b8, esi at 0xffffd7b0, edi at 0xffffd7b4,
117 ** ------------------------------------------------------------------------
120 /* -- GDB JIT API --------------------------------------------------------- */
122 /* GDB JIT actions. */
130 typedef struct GDBJITentry
{
131 struct GDBJITentry
*next_entry
;
132 struct GDBJITentry
*prev_entry
;
133 const char *symfile_addr
;
134 uint64_t symfile_size
;
137 /* GDB JIT descriptor. */
138 typedef struct GDBJITdesc
{
140 uint32_t action_flag
;
141 GDBJITentry
*relevant_entry
;
142 GDBJITentry
*first_entry
;
145 GDBJITdesc __jit_debug_descriptor
= {
146 1, GDBJIT_NOACTION
, NULL
, NULL
149 /* GDB sets a breakpoint at this function. */
150 void LJ_NOINLINE
__jit_debug_register_code()
152 __asm__
__volatile__("");
155 /* -- In-memory ELF object definitions ------------------------------------ */
157 /* ELF definitions. */
158 typedef struct ELFheader
{
181 typedef struct ELFsectheader
{
194 #define ELFSECT_IDX_ABS 0xfff1
197 ELFSECT_TYPE_PROGBITS
= 1,
198 ELFSECT_TYPE_SYMTAB
= 2,
199 ELFSECT_TYPE_STRTAB
= 3,
200 ELFSECT_TYPE_NOBITS
= 8
203 #define ELFSECT_FLAGS_WRITE 1
204 #define ELFSECT_FLAGS_ALLOC 2
205 #define ELFSECT_FLAGS_EXEC 4
207 typedef struct ELFsymbol
{
226 ELFSYM_TYPE_FUNC
= 2,
227 ELFSYM_TYPE_FILE
= 4,
228 ELFSYM_BIND_LOCAL
= 0 << 4,
229 ELFSYM_BIND_GLOBAL
= 1 << 4,
232 /* DWARF definitions. */
233 #define DW_CIE_VERSION 1
237 DW_CFA_offset_extended
= 0x5,
238 DW_CFA_def_cfa
= 0xc,
239 DW_CFA_def_cfa_offset
= 0xe,
240 DW_CFA_offset_extended_sf
= 0x11,
241 DW_CFA_advance_loc
= 0x40,
247 DW_EH_PE_textrel
= 0x20
251 DW_TAG_compile_unit
= 0x11
261 DW_AT_stmt_list
= 0x10,
268 DW_FORM_data4
= 0x06,
269 DW_FORM_string
= 0x08
273 DW_LNS_extended_op
= 0,
275 DW_LNS_advance_pc
= 2,
276 DW_LNS_advance_line
= 3
280 DW_LNE_end_sequence
= 1,
281 DW_LNE_set_address
= 2
286 DW_REG_AX
, DW_REG_CX
, DW_REG_DX
, DW_REG_BX
,
287 DW_REG_SP
, DW_REG_BP
, DW_REG_SI
, DW_REG_DI
,
290 /* Yes, the order is strange, but correct. */
291 DW_REG_AX
, DW_REG_DX
, DW_REG_CX
, DW_REG_BX
,
292 DW_REG_SI
, DW_REG_DI
, DW_REG_BP
, DW_REG_SP
,
293 DW_REG_8
, DW_REG_9
, DW_REG_10
, DW_REG_11
,
294 DW_REG_12
, DW_REG_13
, DW_REG_14
, DW_REG_15
,
307 #error "Unsupported target architecture"
311 /* Minimal list of sections for the in-memory ELF object. */
315 GDBJIT_SECT_eh_frame
,
316 GDBJIT_SECT_shstrtab
,
319 GDBJIT_SECT_debug_info
,
320 GDBJIT_SECT_debug_abbrev
,
321 GDBJIT_SECT_debug_line
,
332 /* In-memory ELF object. */
333 typedef struct GDBJITobj
{
334 ELFheader hdr
; /* ELF header. */
335 ELFsectheader sect
[GDBJIT_SECT__MAX
]; /* ELF sections. */
336 ELFsymbol sym
[GDBJIT_SYM__MAX
]; /* ELF symbol table. */
337 uint8_t space
[4096]; /* Space for various section data. */
340 /* Combined structure for GDB JIT entry and ELF object. */
341 typedef struct GDBJITentryobj
{
347 /* Template for in-memory ELF header. */
348 static const ELFheader elfhdr_template
= {
349 .emagic
= { 0x7f, 'E', 'L', 'F' },
350 .eclass
= LJ_64
? 2 : 1,
351 .eendian
= LJ_ENDIAN_SELECT(1, 2),
354 .eosabi
= 0, /* Nope, it's not 3. */
355 #elif defined(__FreeBSD__)
357 #elif defined(__NetBSD__)
359 #elif defined(__OpenBSD__)
361 #elif defined(__DragonFly__)
363 #elif (defined(__sun__) && defined(__svr4__))
369 .epad
= { 0, 0, 0, 0, 0, 0, 0 },
382 #error "Unsupported target architecture"
387 .shofs
= offsetof(GDBJITobj
, sect
),
389 .ehsize
= sizeof(ELFheader
),
392 .shentsize
= sizeof(ELFsectheader
),
393 .shnum
= GDBJIT_SECT__MAX
,
394 .shstridx
= GDBJIT_SECT_shstrtab
397 /* -- In-memory ELF object generation ------------------------------------- */
399 /* Context for generating the ELF object for the GDB JIT API. */
400 typedef struct GDBJITctx
{
401 uint8_t *p
; /* Pointer to next address in obj.space. */
402 uint8_t *startp
; /* Pointer to start address in obj.space. */
403 GCtrace
*T
; /* Generate symbols for this trace. */
404 uintptr_t mcaddr
; /* Machine code address. */
405 MSize szmcode
; /* Size of machine code. */
406 MSize spadjp
; /* Stack adjustment for parent trace or interpreter. */
407 MSize spadj
; /* Stack adjustment for trace itself. */
408 BCLine lineno
; /* Starting line number. */
409 const char *filename
; /* Starting file name. */
410 size_t objsize
; /* Final size of ELF object. */
411 GDBJITobj obj
; /* In-memory ELF object. */
414 /* Add a zero-terminated string. */
415 static uint32_t gdbjit_strz(GDBJITctx
*ctx
, const char *str
)
418 uint32_t ofs
= (uint32_t)(p
- ctx
->startp
);
420 *p
++ = (uint8_t)*str
;
426 /* Append a decimal number. */
427 static void gdbjit_catnum(GDBJITctx
*ctx
, uint32_t n
)
429 if (n
>= 10) { uint32_t m
= n
/ 10; n
= n
% 10; gdbjit_catnum(ctx
, m
); }
433 /* Add a SLEB128 value. */
434 static void gdbjit_sleb128(GDBJITctx
*ctx
, int32_t v
)
437 for (; (uint32_t)(v
+0x40) >= 0x80; v
>>= 7)
438 *p
++ = (uint8_t)((v
& 0x7f) | 0x80);
439 *p
++ = (uint8_t)(v
& 0x7f);
443 /* Shortcuts to generate DWARF structures. */
444 #define DB(x) (*p++ = (x))
445 #define DI8(x) (*(int8_t *)p = (x), p++)
446 #define DU16(x) (*(uint16_t *)p = (x), p += 2)
447 #define DU32(x) (*(uint32_t *)p = (x), p += 4)
448 #define DADDR(x) (*(uintptr_t *)p = (x), p += sizeof(uintptr_t))
449 #define DUV(x) (p = (uint8_t *)lj_strfmt_wuleb128((char *)p, (x)))
450 #define DSV(x) (ctx->p = p, gdbjit_sleb128(ctx, (x)), p = ctx->p)
451 #define DSTR(str) (ctx->p = p, gdbjit_strz(ctx, (str)), p = ctx->p)
452 #define DALIGNNOP(s) while ((uintptr_t)p & ((s)-1)) *p++ = DW_CFA_nop
453 #define DSECT(name, stmt) \
454 { uint32_t *szp_##name = (uint32_t *)p; p += 4; stmt \
455 *szp_##name = (uint32_t)((p-(uint8_t *)szp_##name)-4); } \
457 /* Initialize ELF section headers. */
458 static void LJ_FASTCALL
gdbjit_secthdr(GDBJITctx
*ctx
)
462 *ctx
->p
++ = '\0'; /* Empty string at start of string table. */
464 #define SECTDEF(id, tp, al) \
465 sect = &ctx->obj.sect[GDBJIT_SECT_##id]; \
466 sect->name = gdbjit_strz(ctx, "." #id); \
467 sect->type = ELFSECT_TYPE_##tp; \
470 SECTDEF(text
, NOBITS
, 16);
471 sect
->flags
= ELFSECT_FLAGS_ALLOC
|ELFSECT_FLAGS_EXEC
;
472 sect
->addr
= ctx
->mcaddr
;
474 sect
->size
= ctx
->szmcode
;
476 SECTDEF(eh_frame
, PROGBITS
, sizeof(uintptr_t));
477 sect
->flags
= ELFSECT_FLAGS_ALLOC
;
479 SECTDEF(shstrtab
, STRTAB
, 1);
480 SECTDEF(strtab
, STRTAB
, 1);
482 SECTDEF(symtab
, SYMTAB
, sizeof(uintptr_t));
483 sect
->ofs
= offsetof(GDBJITobj
, sym
);
484 sect
->size
= sizeof(ctx
->obj
.sym
);
485 sect
->link
= GDBJIT_SECT_strtab
;
486 sect
->entsize
= sizeof(ELFsymbol
);
487 sect
->info
= GDBJIT_SYM_FUNC
;
489 SECTDEF(debug_info
, PROGBITS
, 1);
490 SECTDEF(debug_abbrev
, PROGBITS
, 1);
491 SECTDEF(debug_line
, PROGBITS
, 1);
496 /* Initialize symbol table. */
497 static void LJ_FASTCALL
gdbjit_symtab(GDBJITctx
*ctx
)
501 *ctx
->p
++ = '\0'; /* Empty string at start of string table. */
503 sym
= &ctx
->obj
.sym
[GDBJIT_SYM_FILE
];
504 sym
->name
= gdbjit_strz(ctx
, "JIT mcode");
505 sym
->sectidx
= ELFSECT_IDX_ABS
;
506 sym
->info
= ELFSYM_TYPE_FILE
|ELFSYM_BIND_LOCAL
;
508 sym
= &ctx
->obj
.sym
[GDBJIT_SYM_FUNC
];
509 sym
->name
= gdbjit_strz(ctx
, "TRACE_"); ctx
->p
--;
510 gdbjit_catnum(ctx
, ctx
->T
->traceno
); *ctx
->p
++ = '\0';
511 sym
->sectidx
= GDBJIT_SECT_text
;
513 sym
->size
= ctx
->szmcode
;
514 sym
->info
= ELFSYM_TYPE_FUNC
|ELFSYM_BIND_GLOBAL
;
517 /* Initialize .eh_frame section. */
518 static void LJ_FASTCALL
gdbjit_ehframe(GDBJITctx
*ctx
)
523 /* Emit DWARF EH CIE. */
525 DU32(0); /* Offset to CIE itself. */
527 DSTR("zR"); /* Augmentation. */
528 DUV(1); /* Code alignment factor. */
529 DSV(-(int32_t)sizeof(uintptr_t)); /* Data alignment factor. */
530 DB(DW_REG_RA
); /* Return address register. */
531 DB(1); DB(DW_EH_PE_textrel
|DW_EH_PE_udata4
); /* Augmentation data. */
532 DB(DW_CFA_def_cfa
); DUV(DW_REG_SP
); DUV(sizeof(uintptr_t));
534 DB(DW_CFA_offset_extended_sf
); DB(DW_REG_RA
); DSV(-1);
536 DB(DW_CFA_offset
|DW_REG_RA
); DUV(1);
538 DALIGNNOP(sizeof(uintptr_t));
541 /* Emit DWARF EH FDE. */
543 DU32((uint32_t)(p
-framep
)); /* Offset to CIE. */
544 DU32(0); /* Machine code offset relative to .text. */
545 DU32(ctx
->szmcode
); /* Machine code length. */
546 DB(0); /* Augmentation data. */
547 /* Registers saved in CFRAME. */
549 DB(DW_CFA_offset
|DW_REG_BP
); DUV(2);
550 DB(DW_CFA_offset
|DW_REG_DI
); DUV(3);
551 DB(DW_CFA_offset
|DW_REG_SI
); DUV(4);
552 DB(DW_CFA_offset
|DW_REG_BX
); DUV(5);
554 DB(DW_CFA_offset
|DW_REG_BP
); DUV(2);
555 DB(DW_CFA_offset
|DW_REG_BX
); DUV(3);
556 DB(DW_CFA_offset
|DW_REG_15
); DUV(4);
557 DB(DW_CFA_offset
|DW_REG_14
); DUV(5);
558 /* Extra registers saved for JIT-compiled code. */
559 DB(DW_CFA_offset
|DW_REG_13
); DUV(9);
560 DB(DW_CFA_offset
|DW_REG_12
); DUV(10);
564 for (i
= 11; i
>= 4; i
--) { DB(DW_CFA_offset
|i
); DUV(2+(11-i
)); }
569 DB(DW_CFA_offset_extended
); DB(DW_REG_CR
); DUV(55);
570 for (i
= 14; i
<= 31; i
++) {
571 DB(DW_CFA_offset
|i
); DUV(37+(31-i
));
572 DB(DW_CFA_offset
|32|i
); DUV(2+2*(31-i
));
578 DB(DW_CFA_offset
|30); DUV(2);
579 for (i
= 23; i
>= 16; i
--) { DB(DW_CFA_offset
|i
); DUV(26-i
); }
580 for (i
= 30; i
>= 20; i
-= 2) { DB(DW_CFA_offset
|32|i
); DUV(42-i
); }
583 #error "Unsupported target architecture"
585 if (ctx
->spadjp
!= ctx
->spadj
) { /* Parent/interpreter stack frame size. */
586 DB(DW_CFA_def_cfa_offset
); DUV(ctx
->spadjp
);
587 DB(DW_CFA_advance_loc
|1); /* Only an approximation. */
589 DB(DW_CFA_def_cfa_offset
); DUV(ctx
->spadj
); /* Trace stack frame size. */
590 DALIGNNOP(sizeof(uintptr_t));
596 /* Initialize .debug_info section. */
597 static void LJ_FASTCALL
gdbjit_debuginfo(GDBJITctx
*ctx
)
602 DU16(2); /* DWARF version. */
603 DU32(0); /* Abbrev offset. */
604 DB(sizeof(uintptr_t)); /* Pointer size. */
606 DUV(1); /* Abbrev #1: DW_TAG_compile_unit. */
607 DSTR(ctx
->filename
); /* DW_AT_name. */
608 DADDR(ctx
->mcaddr
); /* DW_AT_low_pc. */
609 DADDR(ctx
->mcaddr
+ ctx
->szmcode
); /* DW_AT_high_pc. */
610 DU32(0); /* DW_AT_stmt_list. */
616 /* Initialize .debug_abbrev section. */
617 static void LJ_FASTCALL
gdbjit_debugabbrev(GDBJITctx
*ctx
)
621 /* Abbrev #1: DW_TAG_compile_unit. */
622 DUV(1); DUV(DW_TAG_compile_unit
);
624 DUV(DW_AT_name
); DUV(DW_FORM_string
);
625 DUV(DW_AT_low_pc
); DUV(DW_FORM_addr
);
626 DUV(DW_AT_high_pc
); DUV(DW_FORM_addr
);
627 DUV(DW_AT_stmt_list
); DUV(DW_FORM_data4
);
633 #define DLNE(op, s) (DB(DW_LNS_extended_op), DUV(1+(s)), DB((op)))
635 /* Initialize .debug_line section. */
636 static void LJ_FASTCALL
gdbjit_debugline(GDBJITctx
*ctx
)
641 DU16(2); /* DWARF version. */
643 DB(1); /* Minimum instruction length. */
644 DB(1); /* is_stmt. */
645 DI8(0); /* Line base for special opcodes. */
646 DB(2); /* Line range for special opcodes. */
647 DB(3+1); /* Opcode base at DW_LNS_advance_line+1. */
648 DB(0); DB(1); DB(1); /* Standard opcode lengths. */
649 /* Directory table. */
651 /* File name table. */
652 DSTR(ctx
->filename
); DUV(0); DUV(0); DUV(0);
656 DLNE(DW_LNE_set_address
, sizeof(uintptr_t)); DADDR(ctx
->mcaddr
);
658 DB(DW_LNS_advance_line
); DSV(ctx
->lineno
-1);
661 DB(DW_LNS_advance_pc
); DUV(ctx
->szmcode
);
662 DLNE(DW_LNE_end_sequence
, 0);
670 /* Undef shortcuts. */
682 /* Type of a section initializer callback. */
683 typedef void (LJ_FASTCALL
*GDBJITinitf
)(GDBJITctx
*ctx
);
685 /* Call section initializer and set the section offset and size. */
686 static void gdbjit_initsect(GDBJITctx
*ctx
, int sect
, GDBJITinitf initf
)
688 ctx
->startp
= ctx
->p
;
689 ctx
->obj
.sect
[sect
].ofs
= (uintptr_t)((char *)ctx
->p
- (char *)&ctx
->obj
);
691 ctx
->obj
.sect
[sect
].size
= (uintptr_t)(ctx
->p
- ctx
->startp
);
694 #define SECTALIGN(p, a) \
695 ((p) = (uint8_t *)(((uintptr_t)(p) + ((a)-1)) & ~(uintptr_t)((a)-1)))
697 /* Build in-memory ELF object. */
698 static void gdbjit_buildobj(GDBJITctx
*ctx
)
700 GDBJITobj
*obj
= &ctx
->obj
;
701 /* Fill in ELF header and clear structures. */
702 memcpy(&obj
->hdr
, &elfhdr_template
, sizeof(ELFheader
));
703 memset(&obj
->sect
, 0, sizeof(ELFsectheader
)*GDBJIT_SECT__MAX
);
704 memset(&obj
->sym
, 0, sizeof(ELFsymbol
)*GDBJIT_SYM__MAX
);
705 /* Initialize sections. */
707 gdbjit_initsect(ctx
, GDBJIT_SECT_shstrtab
, gdbjit_secthdr
);
708 gdbjit_initsect(ctx
, GDBJIT_SECT_strtab
, gdbjit_symtab
);
709 gdbjit_initsect(ctx
, GDBJIT_SECT_debug_info
, gdbjit_debuginfo
);
710 gdbjit_initsect(ctx
, GDBJIT_SECT_debug_abbrev
, gdbjit_debugabbrev
);
711 gdbjit_initsect(ctx
, GDBJIT_SECT_debug_line
, gdbjit_debugline
);
712 SECTALIGN(ctx
->p
, sizeof(uintptr_t));
713 gdbjit_initsect(ctx
, GDBJIT_SECT_eh_frame
, gdbjit_ehframe
);
714 ctx
->objsize
= (size_t)((char *)ctx
->p
- (char *)obj
);
715 lua_assert(ctx
->objsize
< sizeof(GDBJITobj
));
720 /* -- Interface to GDB JIT API -------------------------------------------- */
722 /* Add new entry to GDB JIT symbol chain. */
723 static void gdbjit_newentry(lua_State
*L
, GDBJITctx
*ctx
)
725 /* Allocate memory for GDB JIT entry and ELF object. */
726 MSize sz
= (MSize
)(sizeof(GDBJITentryobj
) - sizeof(GDBJITobj
) + ctx
->objsize
);
727 GDBJITentryobj
*eo
= lj_mem_newt(L
, sz
, GDBJITentryobj
);
728 memcpy(&eo
->obj
, &ctx
->obj
, ctx
->objsize
); /* Copy ELF object. */
730 ctx
->T
->gdbjit_entry
= (void *)eo
;
731 /* Link new entry to chain and register it. */
732 eo
->entry
.prev_entry
= NULL
;
733 eo
->entry
.next_entry
= __jit_debug_descriptor
.first_entry
;
734 if (eo
->entry
.next_entry
)
735 eo
->entry
.next_entry
->prev_entry
= &eo
->entry
;
736 eo
->entry
.symfile_addr
= (const char *)&eo
->obj
;
737 eo
->entry
.symfile_size
= ctx
->objsize
;
738 __jit_debug_descriptor
.first_entry
= &eo
->entry
;
739 __jit_debug_descriptor
.relevant_entry
= &eo
->entry
;
740 __jit_debug_descriptor
.action_flag
= GDBJIT_REGISTER
;
741 __jit_debug_register_code();
744 /* Add debug info for newly compiled trace and notify GDB. */
745 void lj_gdbjit_addtrace(jit_State
*J
, GCtrace
*T
)
748 GCproto
*pt
= &gcref(T
->startpt
)->pt
;
749 TraceNo parent
= T
->ir
[REF_BASE
].op1
;
750 const BCIns
*startpc
= mref(T
->startpc
, const BCIns
);
752 ctx
.mcaddr
= (uintptr_t)T
->mcode
;
753 ctx
.szmcode
= T
->szmcode
;
754 ctx
.spadjp
= CFRAME_SIZE_JIT
+
755 (MSize
)(parent
? traceref(J
, parent
)->spadjust
: 0);
756 ctx
.spadj
= CFRAME_SIZE_JIT
+ T
->spadjust
;
757 lua_assert(startpc
>= proto_bc(pt
) && startpc
< proto_bc(pt
) + pt
->sizebc
);
758 ctx
.lineno
= lj_debug_line(pt
, proto_bcpos(pt
, startpc
));
759 ctx
.filename
= proto_chunknamestr(pt
);
760 if (*ctx
.filename
== '@' || *ctx
.filename
== '=')
763 ctx
.filename
= "(string)";
764 gdbjit_buildobj(&ctx
);
765 gdbjit_newentry(J
->L
, &ctx
);
768 /* Delete debug info for trace and notify GDB. */
769 void lj_gdbjit_deltrace(jit_State
*J
, GCtrace
*T
)
771 GDBJITentryobj
*eo
= (GDBJITentryobj
*)T
->gdbjit_entry
;
773 if (eo
->entry
.prev_entry
)
774 eo
->entry
.prev_entry
->next_entry
= eo
->entry
.next_entry
;
776 __jit_debug_descriptor
.first_entry
= eo
->entry
.next_entry
;
777 if (eo
->entry
.next_entry
)
778 eo
->entry
.next_entry
->prev_entry
= eo
->entry
.prev_entry
;
779 __jit_debug_descriptor
.relevant_entry
= &eo
->entry
;
780 __jit_debug_descriptor
.action_flag
= GDBJIT_UNREGISTER
;
781 __jit_debug_register_code();
782 lj_mem_free(J2G(J
), eo
, eo
->sz
);