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      1 
      2 /*--------------------------------------------------------------------*/
      3 /*--- The core/tool interface.                pub_tool_tooliface.h ---*/
      4 /*--------------------------------------------------------------------*/
      5 
      6 /*
      7    This file is part of Valgrind, a dynamic binary instrumentation
      8    framework.
      9 
     10    Copyright (C) 2000-2017 Julian Seward
     11       jseward (at) acm.org
     12 
     13    This program is free software; you can redistribute it and/or
     14    modify it under the terms of the GNU General Public License as
     15    published by the Free Software Foundation; either version 2 of the
     16    License, or (at your option) any later version.
     17 
     18    This program is distributed in the hope that it will be useful, but
     19    WITHOUT ANY WARRANTY; without even the implied warranty of
     20    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     21    General Public License for more details.
     22 
     23    You should have received a copy of the GNU General Public License
     24    along with this program; if not, write to the Free Software
     25    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
     26    02111-1307, USA.
     27 
     28    The GNU General Public License is contained in the file COPYING.
     29 */
     30 
     31 #ifndef __PUB_TOOL_TOOLIFACE_H
     32 #define __PUB_TOOL_TOOLIFACE_H
     33 
     34 #include "pub_tool_errormgr.h"   // for Error, Supp
     35 #include "libvex.h"              // for all Vex stuff
     36 
     37 /* ------------------------------------------------------------------ */
     38 /* The interface version */
     39 
     40 /* Initialise tool.   Must do the following:
     41    - initialise the `details' struct, via the VG_(details_*)() functions
     42    - register the basic tool functions, via VG_(basic_tool_funcs)().
     43    May do the following:
     44    - initialise the `needs' struct to indicate certain requirements, via
     45      the VG_(needs_*)() functions
     46    - any other tool-specific initialisation
     47 */
     48 extern void (*VG_(tl_pre_clo_init)) ( void );
     49 
     50 /* Every tool must include this macro somewhere, exactly once.  The
     51    interface version is no longer relevant, but we kept the same name
     52    to avoid requiring changes to tools.
     53 */
     54 #define VG_DETERMINE_INTERFACE_VERSION(pre_clo_init) \
     55    void (*VG_(tl_pre_clo_init)) ( void ) = pre_clo_init;
     56 
     57 /* ------------------------------------------------------------------ */
     58 /* Basic tool functions */
     59 
     60 /* The tool_instrument function is passed as a callback to
     61    LibVEX_Translate.  VgCallbackClosure carries additional info
     62    which the instrumenter might like to know, but which is opaque to
     63    Vex.
     64 */
     65 typedef
     66    struct {
     67       Addr     nraddr; /* non-redirected guest address */
     68       Addr     readdr; /* redirected guest address */
     69       ThreadId tid;    /* tid requesting translation */
     70    }
     71    VgCallbackClosure;
     72 
     73 extern void VG_(basic_tool_funcs)(
     74    // Do any initialisation that can only be done after command line
     75    // processing.
     76    void  (*post_clo_init)(void),
     77 
     78    // Instrument a basic block.  Must be a true function, ie. the same
     79    // input always results in the same output, because basic blocks
     80    // can be retranslated, unless you're doing something really
     81    // strange.  Anyway, the arguments.  Mostly they are straightforward
     82    // except for the distinction between redirected and non-redirected
     83    // guest code addresses, which is important to understand.
     84    //
     85    // VgCallBackClosure* closure contains extra arguments passed
     86    // from Valgrind to the instrumenter, which Vex doesn't know about.
     87    // You are free to look inside this structure.
     88    //
     89    // * closure->tid is the ThreadId of the thread requesting the
     90    //   translation.  Not sure why this is here; perhaps callgrind
     91    //   uses it.
     92    //
     93    // * closure->nraddr is the non-redirected guest address of the
     94    //   start of the translation.  In other words, the translation is
     95    //   being constructed because the guest program jumped to
     96    //   closure->nraddr but no translation of it was found.
     97    //
     98    // * closure->readdr is the redirected guest address, from which
     99    //   the translation was really made.
    100    //
    101    //   To clarify this, consider what happens when, in Memcheck, the
    102    //   first call to malloc() happens.  The guest program will be
    103    //   trying to jump to malloc() in libc; hence ->nraddr will contain
    104    //   that address.  However, Memcheck intercepts and replaces
    105    //   malloc, hence ->readdr will be the address of Memcheck's
    106    //   malloc replacement in
    107    //   coregrind/m_replacemalloc/vg_replacemalloc.c.  It follows
    108    //   that the first IMark in the translation will be labelled as
    109    //   from ->readdr rather than ->nraddr.
    110    //
    111    //   Since most functions are not redirected, the majority of the
    112    //   time ->nraddr will be the same as ->readdr.  However, you
    113    //   cannot assume this: if your tool has metadata associated
    114    //   with code addresses it will get into deep trouble if it does
    115    //   make this assumption.
    116    //
    117    // IRSB* sb_in is the incoming superblock to be instrumented,
    118    // in flat IR form.
    119    //
    120    // VexGuestLayout* layout contains limited info on the layout of
    121    // the guest state: where the stack pointer and program counter
    122    // are, and which fields should be regarded as 'always defined'.
    123    // Memcheck uses this.
    124    //
    125    // VexGuestExtents* vge points to a structure which states the
    126    // precise byte ranges of original code from which this translation
    127    // was made (there may be up to three different ranges involved).
    128    // Note again that these are the real addresses from which the code
    129    // came.  And so it should be the case that closure->readdr is the
    130    // same as vge->base[0]; indeed Cachegrind contains this assertion.
    131    //
    132    // Tools which associate shadow data with code addresses
    133    // (cachegrind, callgrind) need to be particularly clear about
    134    // whether they are making the association with redirected or
    135    // non-redirected code addresses.  Both approaches are viable
    136    // but you do need to understand what's going on.  See comments
    137    // below on discard_basic_block_info().
    138    //
    139    // IRType gWordTy and IRType hWordTy contain the types of native
    140    // words on the guest (simulated) and host (real) CPUs.  They will
    141    // by either Ity_I32 or Ity_I64.  So far we have never built a
    142    // cross-architecture Valgrind so they should always be the same.
    143    //
    144    /* --- Further comments about the IR that your --- */
    145    /* --- instrumentation function will receive. --- */
    146    /*
    147       In the incoming IRSB, the IR for each instruction begins with an
    148       IRStmt_IMark, which states the address and length of the
    149       instruction from which this IR came.  This makes it easy for
    150       profiling-style tools to know precisely which guest code
    151       addresses are being executed.
    152 
    153       However, before the first IRStmt_IMark, there may be other IR
    154       statements -- a preamble.  In most cases this preamble is empty,
    155       but when it isn't, what it contains is some supporting IR that
    156       the JIT uses to ensure control flow works correctly.  This
    157       preamble does not modify any architecturally defined guest state
    158       (registers or memory) and so does not contain anything that will
    159       be of interest to your tool.
    160 
    161       You should therefore
    162 
    163       (1) copy any IR preceding the first IMark verbatim to the start
    164           of the output IRSB.
    165 
    166       (2) not try to instrument it or modify it in any way.
    167 
    168       For the record, stuff that may be in the preamble at
    169       present is:
    170 
    171       - A self-modifying-code check has been requested for this block.
    172         The preamble will contain instructions to checksum the block,
    173         compare against the expected value, and exit the dispatcher
    174         requesting a discard (hence forcing a retranslation) if they
    175         don't match.
    176 
    177       - This block is known to be the entry point of a wrapper of some
    178         function F.  In this case the preamble contains code to write
    179         the address of the original F (the fn being wrapped) into a
    180         'hidden' guest state register _NRADDR.  The wrapper can later
    181         read this register using a client request and make a
    182         non-redirected call to it using another client-request-like
    183         magic macro.
    184 
    185       - For platforms that use the AIX ABI (including ppc64-linux), it
    186         is necessary to have a preamble even for replacement functions
    187         (not just for wrappers), because it is necessary to switch the
    188         R2 register (constant-pool pointer) to a different value when
    189         swizzling the program counter.
    190 
    191         Hence the preamble pushes both R2 and LR (the return address)
    192         on a small 16-entry stack in the guest state and sets R2 to an
    193         appropriate value for the wrapper/replacement fn.  LR is then
    194         set so that the wrapper/replacement fn returns to a magic IR
    195         stub which restores R2 and LR and returns.
    196 
    197         It's all hugely ugly and fragile.  And it places a stringent
    198         requirement on m_debuginfo to find out the correct R2 (toc
    199         pointer) value for the wrapper/replacement function.  So much
    200         so that m_redir will refuse to honour a redirect-to-me request
    201         if it cannot find (by asking m_debuginfo) a plausible R2 value
    202         for 'me'.
    203 
    204         Because this mechanism maintains a shadow stack of (R2,LR)
    205         pairs in the guest state, it will fail if the
    206         wrapper/redirection function, or anything it calls, longjumps
    207         out past the wrapper, because then the magic return stub will
    208         not be run and so the shadow stack will not be popped.  So it
    209         will quickly fill up.  Fortunately none of this applies to
    210         {x86,amd64,ppc32}-linux; on those platforms, wrappers can
    211         longjump and recurse arbitrarily and everything should work
    212         fine.
    213 
    214       Note that copying the preamble verbatim may cause complications
    215       for your instrumenter if you shadow IR temporaries.  See big
    216       comment in MC_(instrument) in memcheck/mc_translate.c for
    217       details.
    218    */
    219    IRSB*(*instrument)(VgCallbackClosure* closure,
    220                       IRSB*              sb_in,
    221                       const VexGuestLayout*  layout,
    222                       const VexGuestExtents* vge,
    223                       const VexArchInfo*     archinfo_host,
    224                       IRType             gWordTy,
    225                       IRType             hWordTy),
    226 
    227    // Finish up, print out any results, etc.  `exitcode' is program's exit
    228    // code.  The shadow can be found with VG_(get_exit_status_shadow)().
    229    void  (*fini)(Int)
    230 );
    231 
    232 /* ------------------------------------------------------------------ */
    233 /* Details */
    234 
    235 /* Default value for avg_translations_sizeB (in bytes), indicating typical
    236    code expansion of about 6:1. */
    237 #define VG_DEFAULT_TRANS_SIZEB   172
    238 
    239 /* Information used in the startup message.  `name' also determines the
    240    string used for identifying suppressions in a suppression file as
    241    belonging to this tool.  `version' can be NULL, in which case (not
    242    surprisingly) no version info is printed; this mechanism is designed for
    243    tools distributed with Valgrind that share a version number with
    244    Valgrind.  Other tools not distributed as part of Valgrind should
    245    probably have their own version number.  */
    246 extern void VG_(details_name)                  ( const HChar* name );
    247 extern void VG_(details_version)               ( const HChar* version );
    248 extern void VG_(details_description)           ( const HChar* description );
    249 extern void VG_(details_copyright_author)      ( const HChar* copyright_author );
    250 
    251 /* Average size of a translation, in bytes, so that the translation
    252    storage machinery can allocate memory appropriately.  Not critical,
    253    setting is optional. */
    254 extern void VG_(details_avg_translation_sizeB) ( UInt size );
    255 
    256 /* String printed if an `tl_assert' assertion fails or VG_(tool_panic)
    257    is called.  Should probably be an email address. */
    258 extern void VG_(details_bug_reports_to)   ( const HChar* bug_reports_to );
    259 
    260 /* ------------------------------------------------------------------ */
    261 /* Needs */
    262 
    263 /* Should __libc_freeres() be run?  Bugs in it can crash the tool. */
    264 extern void VG_(needs_libc_freeres) ( void );
    265 
    266 /* Should __gnu_cxx::__freeres() be run?  Bugs in it can crash the tool. */
    267 extern void VG_(needs_cxx_freeres) ( void );
    268 
    269 /* Want to have errors detected by Valgrind's core reported?  Includes:
    270    - pthread API errors (many;  eg. unlocking a non-locked mutex)
    271      [currently disabled]
    272    - invalid file descriptors to syscalls like read() and write()
    273    - bad signal numbers passed to sigaction()
    274    - attempt to install signal handler for SIGKILL or SIGSTOP */
    275 extern void VG_(needs_core_errors) ( void );
    276 
    277 /* Booleans that indicate extra operations are defined;  if these are True,
    278    the corresponding template functions (given below) must be defined.  A
    279    lot like being a member of a type class. */
    280 
    281 /* Want to report errors from tool?  This implies use of suppressions, too. */
    282 extern void VG_(needs_tool_errors) (
    283    // Identify if two errors are equal, or close enough.  This function is
    284    // only called if e1 and e2 will have the same error kind.  `res' indicates
    285    // how close is "close enough".  `res' should be passed on as necessary,
    286    // eg. if the Error's `extra' part contains an ExeContext, `res' should be
    287    // passed to VG_(eq_ExeContext)() if the ExeContexts are considered.  Other
    288    // than that, probably don't worry about it unless you have lots of very
    289    // similar errors occurring.
    290    Bool (*eq_Error)(VgRes res, const Error* e1, const Error* e2),
    291 
    292    // We give tools a chance to have a look at errors
    293    // just before they are printed.  That is, before_pp_Error is
    294    // called just before pp_Error itself.  This gives the tool a
    295    // chance to look at the just-about-to-be-printed error, so as to
    296    // emit any arbitrary output if wants to, before the error itself
    297    // is printed.  This functionality was added to allow Helgrind to
    298    // print thread-announcement messages immediately before the
    299    // errors that refer to them.
    300    void (*before_pp_Error)(const Error* err),
    301 
    302    // Print error context.
    303    void (*pp_Error)(const Error* err),
    304 
    305    // Should the core indicate which ThreadId each error comes from?
    306    Bool show_ThreadIDs_for_errors,
    307 
    308    // Should fill in any details that could be postponed until after the
    309    // decision whether to ignore the error (ie. details not affecting the
    310    // result of VG_(tdict).tool_eq_Error()).  This saves time when errors
    311    // are ignored.
    312    // Yuk.
    313    // Return value: must be the size of the `extra' part in bytes -- used by
    314    // the core to make a copy.
    315    UInt (*update_extra)(const Error* err),
    316 
    317    // Return value indicates recognition.  If recognised, must set skind using
    318    // VG_(set_supp_kind)().
    319    Bool (*recognised_suppression)(const HChar* name, Supp* su),
    320 
    321    // Read any extra info for this suppression kind.  Most likely for filling
    322    // in the `extra' and `string' parts (with VG_(set_supp_{extra, string})())
    323    // of a suppression if necessary.  Should return False if a syntax error
    324    // occurred, True otherwise.
    325    // fd, bufpp, nBufp and lineno are the same as for VG_(get_line).
    326    Bool (*read_extra_suppression_info)(Int fd, HChar** bufpp, SizeT* nBufp,
    327                                        Int* lineno, Supp* su),
    328 
    329    // This should just check the kinds match and maybe some stuff in the
    330    // `string' and `extra' field if appropriate (using VG_(get_supp_*)() to
    331    // get the relevant suppression parts).
    332    Bool (*error_matches_suppression)(const Error* err, const Supp* su),
    333 
    334    // This should return the suppression name, for --gen-suppressions, or NULL
    335    // if that error type cannot be suppressed.  This is the inverse of
    336    // VG_(tdict).tool_recognised_suppression().
    337    const HChar* (*get_error_name)(const Error* err),
    338 
    339    // This should print into buf[0..nBuf-1] any extra info for the
    340    // error, for --gen-suppressions, but not including any leading
    341    // spaces nor a trailing newline.  The string needs to be null
    342    // terminated. If the buffer is large enough to hold the string
    343    // including the terminating null character the function shall
    344    // return the value that strlen would return for the string.
    345    // If the buffer is too small the function shall return nBuf.
    346    SizeT (*print_extra_suppression_info)(const Error* err,
    347                                          /*OUT*/HChar* buf, Int nBuf),
    348 
    349    // This is similar to print_extra_suppression_info, but is used
    350    // to print information such as additional statistical counters
    351    // as part of the used suppression list produced by -v.
    352    SizeT (*print_extra_suppression_use)(const Supp* su,
    353                                         /*OUT*/HChar* buf, Int nBuf),
    354 
    355    // Called by error mgr once it has been established that err
    356    // is suppressed by su. update_extra_suppression_use typically
    357    // can be used to update suppression extra information such as
    358    // some statistical counters that will be printed by
    359    // print_extra_suppression_use.
    360    void (*update_extra_suppression_use)(const Error* err, const Supp* su)
    361 );
    362 
    363 /* Is information kept by the tool about specific instructions or
    364    translations?  (Eg. for cachegrind there are cost-centres for every
    365    instruction, stored in a per-translation fashion.)  If so, the info
    366    may have to be discarded when translations are unloaded (eg. due to
    367    .so unloading, or otherwise at the discretion of m_transtab, eg
    368    when the table becomes too full) to avoid stale information being
    369    reused for new translations. */
    370 extern void VG_(needs_superblock_discards) (
    371    // Discard any information that pertains to specific translations
    372    // or instructions within the address range given.  There are two
    373    // possible approaches.
    374    // - If info is being stored at a per-translation level, use orig_addr
    375    //   to identify which translation is being discarded.  Each translation
    376    //   will be discarded exactly once.
    377    //   This orig_addr will match the closure->nraddr which was passed to
    378    //   to instrument() (see extensive comments above) when this
    379    //   translation was made.  Note that orig_addr won't necessarily be
    380    //   the same as the first address in "extents".
    381    // - If info is being stored at a per-instruction level, you can get
    382    //   the address range(s) being discarded by stepping through "extents".
    383    //   Note that any single instruction may belong to more than one
    384    //   translation, and so could be covered by the "extents" of more than
    385    //   one call to this function.
    386    // Doing it the first way (as eg. Cachegrind does) is probably easier.
    387    void (*discard_superblock_info)(Addr orig_addr, VexGuestExtents extents)
    388 );
    389 
    390 /* Tool defines its own command line options? */
    391 extern void VG_(needs_command_line_options) (
    392    // Return True if option was recognised, False if it wasn't (but also see
    393    // below).  Presumably sets some state to record the option as well.
    394    //
    395    // Nb: tools can assume that the argv will never disappear.  So they can,
    396    // for example, store a pointer to a string within an option, rather than
    397    // having to make a copy.
    398    //
    399    // Options (and combinations of options) should be checked in this function
    400    // if possible rather than in post_clo_init(), and if they are bad then
    401    // VG_(fmsg_bad_option)() should be called.  This ensures that the
    402    // messaging is consistent with command line option errors from the core.
    403    Bool (*process_cmd_line_option)(const HChar* argv),
    404 
    405    // Print out command line usage for options for normal tool operation.
    406    void (*print_usage)(void),
    407 
    408    // Print out command line usage for options for debugging the tool.
    409    void (*print_debug_usage)(void)
    410 );
    411 
    412 /* Tool defines its own client requests? */
    413 extern void VG_(needs_client_requests) (
    414    // If using client requests, the number of the first request should be equal
    415    // to VG_USERREQ_TOOL_BASE('X', 'Y'), where 'X' and 'Y' form a suitable two
    416    // character identification for the string.  The second and subsequent
    417    // requests should follow.
    418    //
    419    // This function should use the VG_IS_TOOL_USERREQ macro (in
    420    // include/valgrind.h) to first check if it's a request for this tool.  Then
    421    // should handle it if it's recognised (and return True), or return False if
    422    // not recognised.  arg_block[0] holds the request number, any further args
    423    // from the request are in arg_block[1..].  'ret' is for the return value...
    424    // it should probably be filled, if only with 0.
    425    Bool (*handle_client_request)(ThreadId tid, UWord* arg_block, UWord* ret)
    426 );
    427 
    428 /* Tool does stuff before and/or after system calls? */
    429 // Nb: If either of the pre_ functions malloc() something to return, the
    430 // corresponding post_ function had better free() it!
    431 // Also, the args are the 'original args' -- that is, it may be
    432 // that the syscall pre-wrapper will modify the args before the
    433 // syscall happens.  So these args are the original, un-modified
    434 // args.  Finally, nArgs merely indicates the length of args[..],
    435 // it does not indicate how many of those values are actually
    436 // relevant to the syscall.  args[0 .. nArgs-1] is guaranteed
    437 // to be defined and to contain all the args for this syscall,
    438 // possibly including some trailing zeroes.
    439 extern void VG_(needs_syscall_wrapper) (
    440                void (* pre_syscall)(ThreadId tid, UInt syscallno,
    441                                     UWord* args, UInt nArgs),
    442                void (*post_syscall)(ThreadId tid, UInt syscallno,
    443                                     UWord* args, UInt nArgs, SysRes res)
    444 );
    445 
    446 /* Are tool-state sanity checks performed? */
    447 // Can be useful for ensuring a tool's correctness.  cheap_sanity_check()
    448 // is called very frequently;  expensive_sanity_check() is called less
    449 // frequently and can be more involved.
    450 extern void VG_(needs_sanity_checks) (
    451    Bool(*cheap_sanity_check)(void),
    452    Bool(*expensive_sanity_check)(void)
    453 );
    454 
    455 /* Can the tool produce stats during execution? */
    456 extern void VG_(needs_print_stats) (
    457    // Print out tool status. Note that the stats at end of execution
    458    // should be output by the VG_(basic_tool_funcs) "fini" function.
    459    void (*print_stats)(void)
    460 );
    461 
    462 /* Has the tool a tool specific function to retrieve and print location info
    463    of an address ? */
    464 extern void VG_(needs_info_location) (
    465    // Get and pp information about Addr
    466    void (*info_location)(Addr)
    467 );
    468 
    469 /* Do we need to see variable type and location information? */
    470 extern void VG_(needs_var_info) ( void );
    471 
    472 /* Does the tool replace malloc() and friends with its own versions?
    473    This has to be combined with the use of a vgpreload_<tool>.so module
    474    or it won't work.  See massif/Makefile.am for how to build it. */
    475 // The 'p' prefix avoids GCC complaints about overshadowing global names.
    476 extern void VG_(needs_malloc_replacement)(
    477    void* (*pmalloc)               ( ThreadId tid, SizeT n ),
    478    void* (*p__builtin_new)        ( ThreadId tid, SizeT n ),
    479    void* (*p__builtin_vec_new)    ( ThreadId tid, SizeT n ),
    480    void* (*pmemalign)             ( ThreadId tid, SizeT align, SizeT n ),
    481    void* (*pcalloc)               ( ThreadId tid, SizeT nmemb, SizeT size1 ),
    482    void  (*pfree)                 ( ThreadId tid, void* p ),
    483    void  (*p__builtin_delete)     ( ThreadId tid, void* p ),
    484    void  (*p__builtin_vec_delete) ( ThreadId tid, void* p ),
    485    void* (*prealloc)              ( ThreadId tid, void* p, SizeT new_size ),
    486    SizeT (*pmalloc_usable_size)   ( ThreadId tid, void* p),
    487    SizeT client_malloc_redzone_szB
    488 );
    489 
    490 /* Can the tool do XML output?  This is a slight misnomer, because the tool
    491  * is not requesting the core to do anything, rather saying "I can handle
    492  * it". */
    493 extern void VG_(needs_xml_output) ( void );
    494 
    495 /* Does the tool want to have one final pass over the IR after tree
    496    building but before instruction selection?  If so specify the
    497    function here. */
    498 extern void VG_(needs_final_IR_tidy_pass) ( IRSB*(*final_tidy)(IRSB*) );
    499 
    500 
    501 /* ------------------------------------------------------------------ */
    502 /* Core events to track */
    503 
    504 /* Part of the core from which this call was made.  Useful for determining
    505    what kind of error message should be emitted. */
    506 typedef
    507    enum { Vg_CoreStartup=1, Vg_CoreSignal, Vg_CoreSysCall,
    508           // This is for platforms where syscall args are passed on the
    509           // stack; although pre_mem_read is the callback that will be
    510           // called, such an arg should be treated (with respect to
    511           // presenting information to the user) as if it was passed in a
    512           // register, ie. like pre_reg_read.
    513           Vg_CoreSysCallArgInMem,
    514           Vg_CoreTranslate, Vg_CoreClientReq
    515    } CorePart;
    516 
    517 /* Events happening in core to track.  To be notified, pass a callback
    518    function to the appropriate function.  To ignore an event, don't do
    519    anything (the default is for events to be ignored).
    520 
    521    Note that most events aren't passed a ThreadId.  If the event is one called
    522    from generated code (eg. new_mem_stack_*), you can use
    523    VG_(get_running_tid)() to find it.  Otherwise, it has to be passed in,
    524    as in pre_mem_read, and so the event signature will require changing.
    525 
    526    Memory events (Nb: to track heap allocation/freeing, a tool must replace
    527    malloc() et al.  See above how to do this.)
    528 
    529    These ones occur at startup, upon some signals, and upon some syscalls.
    530 
    531    For new_mem_brk and new_mem_stack_signal, the supplied ThreadId
    532    indicates the thread for whom the new memory is being allocated.
    533 
    534    For new_mem_startup and new_mem_mmap, the di_handle argument is a
    535    handle which can be used to retrieve debug info associated with the
    536    mapping or allocation (because it is of a file that Valgrind has
    537    decided to read debug info from).  If the value is zero, there is
    538    no associated debug info.  If the value exceeds zero, it can be
    539    supplied as an argument to selected queries in m_debuginfo.
    540 */
    541 void VG_(track_new_mem_startup)     (void(*f)(Addr a, SizeT len,
    542                                               Bool rr, Bool ww, Bool xx,
    543                                               ULong di_handle));
    544 void VG_(track_new_mem_stack_signal)(void(*f)(Addr a, SizeT len, ThreadId tid));
    545 void VG_(track_new_mem_brk)         (void(*f)(Addr a, SizeT len, ThreadId tid));
    546 void VG_(track_new_mem_mmap)        (void(*f)(Addr a, SizeT len,
    547                                               Bool rr, Bool ww, Bool xx,
    548                                               ULong di_handle));
    549 
    550 void VG_(track_copy_mem_remap)      (void(*f)(Addr from, Addr to, SizeT len));
    551 void VG_(track_change_mem_mprotect) (void(*f)(Addr a, SizeT len,
    552                                               Bool rr, Bool ww, Bool xx));
    553 void VG_(track_die_mem_stack_signal)(void(*f)(Addr a, SizeT len));
    554 void VG_(track_die_mem_brk)         (void(*f)(Addr a, SizeT len));
    555 void VG_(track_die_mem_munmap)      (void(*f)(Addr a, SizeT len));
    556 
    557 /* These ones are called when SP changes.  A tool could track these itself
    558    (except for ban_mem_stack) but it's much easier to use the core's help.
    559 
    560    The specialised ones are called in preference to the general one, if they
    561    are defined.  These functions are called a lot if they are used, so
    562    specialising can optimise things significantly.  If any of the
    563    specialised cases are defined, the general case must be defined too.
    564 
    565    Nb: all the specialised ones must use the VG_REGPARM(n) attribute.
    566 
    567    For the _new functions, a tool may specify with with-ECU
    568    (ExeContext Unique) or without-ECU version for each size, but not
    569    both.  If the with-ECU version is supplied, then the core will
    570    arrange to pass, as the ecu argument, a 32-bit int which uniquely
    571    identifies the instruction moving the stack pointer down.  This
    572    32-bit value is as obtained from VG_(get_ECU_from_ExeContext).
    573    VG_(get_ExeContext_from_ECU) can then be used to retrieve the
    574    associated depth-1 ExeContext for the location.  All this
    575    complexity is provided to support origin tracking in Memcheck.
    576 */
    577 void VG_(track_new_mem_stack_4_w_ECU)  (VG_REGPARM(2) void(*f)(Addr new_ESP, UInt ecu));
    578 void VG_(track_new_mem_stack_8_w_ECU)  (VG_REGPARM(2) void(*f)(Addr new_ESP, UInt ecu));
    579 void VG_(track_new_mem_stack_12_w_ECU) (VG_REGPARM(2) void(*f)(Addr new_ESP, UInt ecu));
    580 void VG_(track_new_mem_stack_16_w_ECU) (VG_REGPARM(2) void(*f)(Addr new_ESP, UInt ecu));
    581 void VG_(track_new_mem_stack_32_w_ECU) (VG_REGPARM(2) void(*f)(Addr new_ESP, UInt ecu));
    582 void VG_(track_new_mem_stack_112_w_ECU)(VG_REGPARM(2) void(*f)(Addr new_ESP, UInt ecu));
    583 void VG_(track_new_mem_stack_128_w_ECU)(VG_REGPARM(2) void(*f)(Addr new_ESP, UInt ecu));
    584 void VG_(track_new_mem_stack_144_w_ECU)(VG_REGPARM(2) void(*f)(Addr new_ESP, UInt ecu));
    585 void VG_(track_new_mem_stack_160_w_ECU)(VG_REGPARM(2) void(*f)(Addr new_ESP, UInt ecu));
    586 void VG_(track_new_mem_stack_w_ECU)                  (void(*f)(Addr a, SizeT len,
    587                                                                        UInt ecu));
    588 
    589 void VG_(track_new_mem_stack_4)  (VG_REGPARM(1) void(*f)(Addr new_ESP));
    590 void VG_(track_new_mem_stack_8)  (VG_REGPARM(1) void(*f)(Addr new_ESP));
    591 void VG_(track_new_mem_stack_12) (VG_REGPARM(1) void(*f)(Addr new_ESP));
    592 void VG_(track_new_mem_stack_16) (VG_REGPARM(1) void(*f)(Addr new_ESP));
    593 void VG_(track_new_mem_stack_32) (VG_REGPARM(1) void(*f)(Addr new_ESP));
    594 void VG_(track_new_mem_stack_112)(VG_REGPARM(1) void(*f)(Addr new_ESP));
    595 void VG_(track_new_mem_stack_128)(VG_REGPARM(1) void(*f)(Addr new_ESP));
    596 void VG_(track_new_mem_stack_144)(VG_REGPARM(1) void(*f)(Addr new_ESP));
    597 void VG_(track_new_mem_stack_160)(VG_REGPARM(1) void(*f)(Addr new_ESP));
    598 void VG_(track_new_mem_stack)                  (void(*f)(Addr a, SizeT len));
    599 
    600 void VG_(track_die_mem_stack_4)  (VG_REGPARM(1) void(*f)(Addr die_ESP));
    601 void VG_(track_die_mem_stack_8)  (VG_REGPARM(1) void(*f)(Addr die_ESP));
    602 void VG_(track_die_mem_stack_12) (VG_REGPARM(1) void(*f)(Addr die_ESP));
    603 void VG_(track_die_mem_stack_16) (VG_REGPARM(1) void(*f)(Addr die_ESP));
    604 void VG_(track_die_mem_stack_32) (VG_REGPARM(1) void(*f)(Addr die_ESP));
    605 void VG_(track_die_mem_stack_112)(VG_REGPARM(1) void(*f)(Addr die_ESP));
    606 void VG_(track_die_mem_stack_128)(VG_REGPARM(1) void(*f)(Addr die_ESP));
    607 void VG_(track_die_mem_stack_144)(VG_REGPARM(1) void(*f)(Addr die_ESP));
    608 void VG_(track_die_mem_stack_160)(VG_REGPARM(1) void(*f)(Addr die_ESP));
    609 void VG_(track_die_mem_stack)                  (void(*f)(Addr a, SizeT len));
    610 
    611 /* Used for redzone at end of thread stacks */
    612 void VG_(track_ban_mem_stack)      (void(*f)(Addr a, SizeT len));
    613 
    614 /* These ones occur around syscalls, signal handling, etc */
    615 void VG_(track_pre_mem_read)       (void(*f)(CorePart part, ThreadId tid,
    616                                              const HChar* s, Addr a, SizeT size));
    617 void VG_(track_pre_mem_read_asciiz)(void(*f)(CorePart part, ThreadId tid,
    618                                              const HChar* s, Addr a));
    619 void VG_(track_pre_mem_write)      (void(*f)(CorePart part, ThreadId tid,
    620                                              const HChar* s, Addr a, SizeT size));
    621 void VG_(track_post_mem_write)     (void(*f)(CorePart part, ThreadId tid,
    622                                              Addr a, SizeT size));
    623 
    624 /* Register events.  Use VG_(set_shadow_state_area)() to set the shadow regs
    625    for these events.  */
    626 void VG_(track_pre_reg_read)  (void(*f)(CorePart part, ThreadId tid,
    627                                         const HChar* s, PtrdiffT guest_state_offset,
    628                                         SizeT size));
    629 void VG_(track_post_reg_write)(void(*f)(CorePart part, ThreadId tid,
    630                                         PtrdiffT guest_state_offset,
    631                                         SizeT size));
    632 
    633 /* This one is called for malloc() et al if they are replaced by a tool. */
    634 void VG_(track_post_reg_write_clientcall_return)(
    635       void(*f)(ThreadId tid, PtrdiffT guest_state_offset, SizeT size, Addr f));
    636 
    637 /* Mem-to-reg or reg-to-mem copy functions, these ones occur around syscalls
    638    and signal handling when the VCPU state is saved to (or restored from) the
    639    client memory. */
    640 void VG_(track_copy_mem_to_reg)(void(*f)(CorePart part, ThreadId tid,
    641                                          Addr a, PtrdiffT guest_state_offset,
    642                                          SizeT size));
    643 void VG_(track_copy_reg_to_mem)(void(*f)(CorePart part, ThreadId tid,
    644                                          PtrdiffT guest_state_offset,
    645                                          Addr a, SizeT size));
    646 
    647 
    648 /* Scheduler events (not exhaustive) */
    649 
    650 /* Called when 'tid' starts or stops running client code blocks.
    651    Gives the total dispatched block count at that event.  Note, this
    652    is not the same as 'tid' holding the BigLock (the lock that ensures
    653    that only one thread runs at a time): a thread can hold the lock
    654    for other purposes (making translations, etc) yet not be running
    655    client blocks.  Obviously though, a thread must hold the lock in
    656    order to run client code blocks, so the times bracketed by
    657    'start_client_code'..'stop_client_code' are a subset of the times
    658    when thread 'tid' holds the cpu lock.
    659 */
    660 void VG_(track_start_client_code)(
    661         void(*f)(ThreadId tid, ULong blocks_dispatched)
    662      );
    663 void VG_(track_stop_client_code)(
    664         void(*f)(ThreadId tid, ULong blocks_dispatched)
    665      );
    666 
    667 
    668 /* Thread events (not exhaustive)
    669 
    670    ll_create: low level thread creation.  Called before the new thread
    671    has run any instructions (or touched any memory).  In fact, called
    672    immediately before the new thread has come into existence; the new
    673    thread can be assumed to exist when notified by this call.
    674 
    675    ll_exit: low level thread exit.  Called after the exiting thread
    676    has run its last instruction.
    677 
    678    The _ll_ part makes it clear these events are not to do with
    679    pthread_create or pthread_exit/pthread_join (etc), which are a
    680    higher level abstraction synthesised by libpthread.  What you can
    681    be sure of from _ll_create/_ll_exit is the absolute limits of each
    682    thread's lifetime, and hence be assured that all memory references
    683    made by the thread fall inside the _ll_create/_ll_exit pair.  This
    684    is important for tools that need a 100% accurate account of which
    685    thread is responsible for every memory reference in the process.
    686 
    687    pthread_create/join/exit do not give this property.  Calls/returns
    688    to/from them happen arbitrarily far away from the relevant
    689    low-level thread create/quit event.  In general a few hundred
    690    instructions; hence a few hundred(ish) memory references could get
    691    misclassified each time.
    692 
    693    pre_thread_first_insn: is called when the thread is all set up and
    694    ready to go (stack in place, etc) but has not executed its first
    695    instruction yet.  Gives threading tools a chance to ask questions
    696    about the thread (eg, what is its initial client stack pointer)
    697    that are not easily answered at pre_thread_ll_create time.
    698 
    699    For a given thread, the call sequence is:
    700       ll_create (in the parent's context)
    701       first_insn (in the child's context)
    702       ll_exit (in the child's context)
    703 */
    704 void VG_(track_pre_thread_ll_create) (void(*f)(ThreadId tid, ThreadId child));
    705 void VG_(track_pre_thread_first_insn)(void(*f)(ThreadId tid));
    706 void VG_(track_pre_thread_ll_exit)   (void(*f)(ThreadId tid));
    707 
    708 
    709 /* Signal events (not exhaustive)
    710 
    711    ... pre_send_signal, post_send_signal ...
    712 
    713    Called before a signal is delivered;  `alt_stack' indicates if it is
    714    delivered on an alternative stack.  */
    715 void VG_(track_pre_deliver_signal) (void(*f)(ThreadId tid, Int sigNo,
    716                                              Bool alt_stack));
    717 /* Called after a signal is delivered.  Nb: unfortunately, if the signal
    718    handler longjmps, this won't be called.  */
    719 void VG_(track_post_deliver_signal)(void(*f)(ThreadId tid, Int sigNo));
    720 
    721 #endif   // __PUB_TOOL_TOOLIFACE_H
    722 
    723 /*--------------------------------------------------------------------*/
    724 /*--- end                                                          ---*/
    725 /*--------------------------------------------------------------------*/
    726