include/valgrind.h

/* -*- c -*-
   ----------------------------------------------------------------

   Notice that the following BSD-style license applies to this one
   file (valgrind.h) only.  The entire rest of Valgrind is licensed
   under the terms of the GNU General Public License, version 2.  See
   the COPYING file in the source distribution for details.

   ----------------------------------------------------------------

   This file is part of Valgrind, a dynamic binary instrumentation
   framework.

   Copyright (C) 2000-2005 Julian Seward.  All rights reserved.

   Redistribution and use in source and binary forms, with or without
   modification, are permitted provided that the following conditions
   are met:

   1. Redistributions of source code must retain the above copyright
      notice, this list of conditions and the following disclaimer.

   2. The origin of this software must not be misrepresented; you must 
      not claim that you wrote the original software.  If you use this 
      software in a product, an acknowledgment in the product 
      documentation would be appreciated but is not required.

   3. Altered source versions must be plainly marked as such, and must
      not be misrepresented as being the original software.

   4. The name of the author may not be used to endorse or promote 
      products derived from this software without specific prior written 
      permission.

   THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
   OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
   WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
   DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
   GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
   WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

   ----------------------------------------------------------------

   Notice that the above BSD-style license applies to this one file
   (valgrind.h) only.  The entire rest of Valgrind is licensed under
   the terms of the GNU General Public License, version 2.  See the
   COPYING file in the source distribution for details.

   ---------------------------------------------------------------- 
*/


/* This file is for inclusion into client (your!) code.

   You can use these macros to manipulate and query Valgrind's 
   execution inside your own programs.

   The resulting executables will still run without Valgrind, just a
   little bit more slowly than they otherwise would, but otherwise
   unchanged.  When not running on valgrind, each client request
   consumes very few (eg. < 10) instructions, so the resulting performance
   loss is negligible unless you plan to execute client requests
   millions of times per second.  Nevertheless, if that is still a
   problem, you can compile with the NVALGRIND symbol defined (gcc
   -DNVALGRIND) so that client requests are not even compiled in.  */

#ifndef __VALGRIND_H
#define __VALGRIND_H

#include <stdarg.h>

/* If we're not compiling for our target architecture, don't generate
   any inline asms.  Note that in this file we're using the compiler's
   CPP symbols for identifying architectures, which are different to
   the ones we use within the rest of Valgrind. */
#if !defined(__i386__) && !defined(__x86_64__)
#  ifndef NVALGRIND
#    define NVALGRIND	1
#  endif  /* NVALGRIND */
#endif

/* ------------------------------------------------------------------ */
/* The architecture-specific part                                     */
/* ------------------------------------------------------------------ */

#ifdef NVALGRIND

/* Define NVALGRIND to completely remove the Valgrind magic sequence
   from the compiled code (analogous to NDEBUG's effects on assert()) */
#define VALGRIND_MAGIC_SEQUENCE(					\
        _zzq_rlval, _zzq_default, _zzq_request,                         \
        _zzq_arg1, _zzq_arg2, _zzq_arg3, _zzq_arg4)                     \
   {									\
      (_zzq_rlval) = (_zzq_default);					\
   }

#else  /* NVALGRIND */

/* The following defines the magic code sequences which the JITter spots and
   handles magically.  Don't look too closely at them; they will rot
   your brain.  We must ensure that the default value gets put in the return
   slot, so that everything works when this is executed not under Valgrind.
   Args are passed in a memory block, and so there's no intrinsic limit to
   the number that could be passed, but it's currently four.
   
   The macro args are: 
      _zzq_rlval    result lvalue
      _zzq_default  default value (result returned when running on real CPU)
      _zzq_request  request code
      _zzq_arg1..4  request params

   Nb: we put the assembly code sequences for all architectures in this one
   file.  This is because this file must be stand-alone, and we don't want
   to have multiple files.
*/

#ifdef __x86_64__
extern int printf (__const char *__restrict __format, ...);
extern void exit (int __status);
#define VALGRIND_MAGIC_SEQUENCE(                                \
        _zzq_rlval, _zzq_default, _zzq_request,                 \
        _zzq_arg1, _zzq_arg2, _zzq_arg3, _zzq_arg4)             \
                                                                \
  { volatile unsigned long long _zzq_args[5];                   \
    _zzq_args[0] = (volatile unsigned long long)(_zzq_request); \
    _zzq_args[1] = (volatile unsigned long long)(_zzq_arg1);    \
    _zzq_args[2] = (volatile unsigned long long)(_zzq_arg2);    \
    _zzq_args[3] = (volatile unsigned long long)(_zzq_arg3);    \
    _zzq_args[4] = (volatile unsigned long long)(_zzq_arg4);    \
    asm volatile("roll $29, %%eax ; roll $3, %%eax\n\t"		\
                 "rorl $27, %%eax ; rorl $5, %%eax\n\t"		\
                 "roll $13, %%eax ; roll $19, %%eax"		\
                 : "=d" (_zzq_rlval)				\
                 : "a" (&_zzq_args[0]), "0" (_zzq_default)	\
                 : "cc", "memory"				\
                );						\
  }
#endif  // __x86_64__

#ifdef __i386__
#define VALGRIND_MAGIC_SEQUENCE(				\
        _zzq_rlval, _zzq_default, _zzq_request,			\
        _zzq_arg1, _zzq_arg2, _zzq_arg3, _zzq_arg4)		\
								\
  { unsigned int _zzq_args[5];					\
    _zzq_args[0] = (unsigned int)(_zzq_request);		\
    _zzq_args[1] = (unsigned int)(_zzq_arg1);			\
    _zzq_args[2] = (unsigned int)(_zzq_arg2);			\
    _zzq_args[3] = (unsigned int)(_zzq_arg3);			\
    _zzq_args[4] = (unsigned int)(_zzq_arg4);			\
    asm volatile("roll $29, %%eax ; roll $3, %%eax\n\t"		\
                 "rorl $27, %%eax ; rorl $5, %%eax\n\t"		\
                 "roll $13, %%eax ; roll $19, %%eax"		\
                 : "=d" (_zzq_rlval)				\
                 : "a" (&_zzq_args[0]), "0" (_zzq_default)	\
                 : "cc", "memory"				\
                );						\
  }
#endif  // __i386__

#ifdef __arm__
// XXX: temporary, until MAGIC_SEQUENCE is written properly
extern int printf (__const char *__restrict __format, ...);
extern void exit (int __status);
#define VALGRIND_MAGIC_SEQUENCE(                                        \
        _zzq_rlval, _zzq_default, _zzq_request,                         \
        _zzq_arg1, _zzq_arg2, _zzq_arg3, _zzq_arg4)                     \
                                                                        \
  { volatile unsigned int _zzq_args[5];                                 \
    _zzq_args[0] = (volatile unsigned int)(_zzq_request);               \
    _zzq_args[1] = (volatile unsigned int)(_zzq_arg1);                  \
    _zzq_args[2] = (volatile unsigned int)(_zzq_arg2);                  \
    _zzq_args[3] = (volatile unsigned int)(_zzq_arg3);                  \
    _zzq_args[4] = (volatile unsigned int)(_zzq_arg4);                  \
    (_zzq_rlval) = (_zzq_default);/* temporary only */  \
    printf("argh: MAGIC_SEQUENCE"); exit(1); \
    asm volatile("");                                                   \
  }
// XXX: make sure that the register holding the args and the register taking
// the return value match what the scheduler is expecting.
#endif  // __arm__

// Insert assembly code for other architectures here...

#endif /* NVALGRIND */


/* ------------------------------------------------------------------ */
/* The architecture-independent part                                  */
/* ------------------------------------------------------------------ */

/* Some request codes.  There are many more of these, but most are not
   exposed to end-user view.  These are the public ones, all of the
   form 0x1000 + small_number.

   Core ones are in the range 0x00000000--0x0000ffff.  The non-public ones
   start at 0x2000.
*/

// These macros are used by tools -- they must be public, but don't embed them
// into other programs.
#define VG_USERREQ_TOOL_BASE(a,b) \
   ((unsigned int)(((a)&0xff) << 24 | ((b)&0xff) << 16))
#define VG_IS_TOOL_USERREQ(a, b, v) \
   (VG_USERREQ_TOOL_BASE(a,b) == ((v) & 0xffff0000))

typedef
   enum { VG_USERREQ__RUNNING_ON_VALGRIND  = 0x1001,
          VG_USERREQ__DISCARD_TRANSLATIONS = 0x1002,

          /* These allow any function to be called from the
             simulated CPU but run on the real CPU.
             Nb: the first arg passed to the function is always the ThreadId of
             the running thread!  So CLIENT_CALL0 actually requires a 1 arg
             function, etc. */
          VG_USERREQ__CLIENT_CALL0 = 0x1101,
          VG_USERREQ__CLIENT_CALL1 = 0x1102,
          VG_USERREQ__CLIENT_CALL2 = 0x1103,
          VG_USERREQ__CLIENT_CALL3 = 0x1104,

          /* Can be useful in regression testing suites -- eg. can send
             Valgrind's output to /dev/null and still count errors. */
          VG_USERREQ__COUNT_ERRORS = 0x1201,

          /* These are useful and can be interpreted by any tool that tracks
             malloc() et al, by using vg_replace_malloc.c. */
          VG_USERREQ__MALLOCLIKE_BLOCK = 0x1301,
          VG_USERREQ__FREELIKE_BLOCK   = 0x1302,
          /* Memory pool support. */
          VG_USERREQ__CREATE_MEMPOOL   = 0x1303,
          VG_USERREQ__DESTROY_MEMPOOL  = 0x1304,
          VG_USERREQ__MEMPOOL_ALLOC    = 0x1305,
          VG_USERREQ__MEMPOOL_FREE     = 0x1306,

          /* Allow printfs to valgrind log. */
          VG_USERREQ__PRINTF           = 0x1401,
          VG_USERREQ__PRINTF_BACKTRACE = 0x1402,

          /* Stack support. */
          VG_USERREQ__STACK_REGISTER   = 0x1501,
          VG_USERREQ__STACK_DEREGISTER = 0x1502,
          VG_USERREQ__STACK_CHANGE     = 0x1503,
   } Vg_ClientRequest;

#ifndef __GNUC__
#define __extension__
#endif

/* Returns the number of Valgrinds this code is running under.  That is,
   0 if running natively, 1 if running under Valgrind, 2 if running under
   Valgrind which is running under another Valgrind, etc. */
#define RUNNING_ON_VALGRIND  __extension__                         \
   ({unsigned int _qzz_res;                                        \
    VALGRIND_MAGIC_SEQUENCE(_qzz_res, 0 /* returned if not */,     \
                            VG_USERREQ__RUNNING_ON_VALGRIND,       \
                            0, 0, 0, 0);                           \
    _qzz_res;                                                      \
   })


/* Discard translation of code in the range [_qzz_addr .. _qzz_addr +
   _qzz_len - 1].  Useful if you are debugging a JITter or some such,
   since it provides a way to make sure valgrind will retranslate the
   invalidated area.  Returns no value. */
#define VALGRIND_DISCARD_TRANSLATIONS(_qzz_addr,_qzz_len)          \
   {unsigned int _qzz_res;                                         \
    VALGRIND_MAGIC_SEQUENCE(_qzz_res, 0,                           \
                            VG_USERREQ__DISCARD_TRANSLATIONS,      \
                            _qzz_addr, _qzz_len, 0, 0);            \
   }

#ifdef NVALGRIND

#define VALGRIND_PRINTF(...)
#define VALGRIND_PRINTF_BACKTRACE(...)

#else /* NVALGRIND */

int VALGRIND_PRINTF(const char *format, ...)
   __attribute__((format(__printf__, 1, 2)));
__attribute__((weak))
int
VALGRIND_PRINTF(const char *format, ...)
{
   unsigned long _qzz_res;
   va_list vargs;
   va_start(vargs, format);
   VALGRIND_MAGIC_SEQUENCE(_qzz_res, 0, VG_USERREQ__PRINTF,
                           (unsigned long)format, (unsigned long)vargs, 0, 0);
   va_end(vargs);
   return (int)_qzz_res;
}

int VALGRIND_PRINTF_BACKTRACE(const char *format, ...)
   __attribute__((format(__printf__, 1, 2)));
__attribute__((weak))
int
VALGRIND_PRINTF_BACKTRACE(const char *format, ...)
{
   unsigned long _qzz_res;
   va_list vargs;
   va_start(vargs, format);
   VALGRIND_MAGIC_SEQUENCE(_qzz_res, 0, VG_USERREQ__PRINTF_BACKTRACE,
                           (unsigned long)format, (unsigned long)vargs, 0, 0);
   va_end(vargs);
   return (int)_qzz_res;
}

#endif /* NVALGRIND */

/* These requests allow control to move from the simulated CPU to the
   real CPU, calling an arbitary function */
#define VALGRIND_NON_SIMD_CALL0(_qyy_fn)                       \
   ({unsigned long _qyy_res;                                   \
    VALGRIND_MAGIC_SEQUENCE(_qyy_res, 0 /* default return */,  \
                            VG_USERREQ__CLIENT_CALL0,          \
                            _qyy_fn,                           \
                            0, 0, 0);                          \
    _qyy_res;                                                  \
   })

#define VALGRIND_NON_SIMD_CALL1(_qyy_fn, _qyy_arg1)            \
   ({unsigned long _qyy_res;                                   \
    VALGRIND_MAGIC_SEQUENCE(_qyy_res, 0 /* default return */,  \
                            VG_USERREQ__CLIENT_CALL1,          \
                            _qyy_fn,                           \
                            _qyy_arg1, 0, 0);                  \
    _qyy_res;                                                  \
   })

#define VALGRIND_NON_SIMD_CALL2(_qyy_fn, _qyy_arg1, _qyy_arg2) \
   ({unsigned long _qyy_res;                                   \
    VALGRIND_MAGIC_SEQUENCE(_qyy_res, 0 /* default return */,  \
                            VG_USERREQ__CLIENT_CALL2,          \
                            _qyy_fn,                           \
                            _qyy_arg1, _qyy_arg2, 0);          \
    _qyy_res;                                                  \
   })

#define VALGRIND_NON_SIMD_CALL3(_qyy_fn, _qyy_arg1, _qyy_arg2, _qyy_arg3)  \
   ({unsigned long _qyy_res;                                         \
    VALGRIND_MAGIC_SEQUENCE(_qyy_res, 0 /* default return */,        \
                            VG_USERREQ__CLIENT_CALL3,                \
                            _qyy_fn,                                 \
                            _qyy_arg1, _qyy_arg2, _qyy_arg3);        \
    _qyy_res;                                                        \
   })


/* Counts the number of errors that have been recorded by a tool.  Nb:
   the tool must record the errors with VG_(maybe_record_error)() or
   VG_(unique_error)() for them to be counted. */
#define VALGRIND_COUNT_ERRORS                                           \
   ({unsigned int _qyy_res;                                             \
    VALGRIND_MAGIC_SEQUENCE(_qyy_res, 0 /* default return */,           \
                            VG_USERREQ__COUNT_ERRORS,                   \
                            0, 0, 0, 0);                                \
    _qyy_res;                                                           \
   })

/* Mark a block of memory as having been allocated by a malloc()-like
   function.  `addr' is the start of the usable block (ie. after any
   redzone) `rzB' is redzone size if the allocator can apply redzones;
   use '0' if not.  Adding redzones makes it more likely Valgrind will spot
   block overruns.  `is_zeroed' indicates if the memory is zeroed, as it is
   for calloc().  Put it immediately after the point where a block is
   allocated. 
   
   If you're allocating memory via superblocks, and then handing out small
   chunks of each superblock, if you don't have redzones on your small
   blocks, it's worth marking the superblock with VALGRIND_MAKE_NOACCESS
   when it's created, so that block overruns are detected.  But if you can
   put redzones on, it's probably better to not do this, so that messages
   for small overruns are described in terms of the small block rather than
   the superblock (but if you have a big overrun that skips over a redzone,
   you could miss an error this way).  See memcheck/tests/custom_alloc.c
   for an example.

   Nb: block must be freed via a free()-like function specified
   with VALGRIND_FREELIKE_BLOCK or mismatch errors will occur. */
#define VALGRIND_MALLOCLIKE_BLOCK(addr, sizeB, rzB, is_zeroed)     \
   {unsigned int _qzz_res;                                         \
    VALGRIND_MAGIC_SEQUENCE(_qzz_res, 0,                           \
                            VG_USERREQ__MALLOCLIKE_BLOCK,          \
                            addr, sizeB, rzB, is_zeroed);          \
   }

/* Mark a block of memory as having been freed by a free()-like function.
   `rzB' is redzone size;  it must match that given to
   VALGRIND_MALLOCLIKE_BLOCK.  Memory not freed will be detected by the leak
   checker.  Put it immediately after the point where the block is freed. */
#define VALGRIND_FREELIKE_BLOCK(addr, rzB)                         \
   {unsigned int _qzz_res;                                         \
    VALGRIND_MAGIC_SEQUENCE(_qzz_res, 0,                           \
                            VG_USERREQ__FREELIKE_BLOCK,            \
                            addr, rzB, 0, 0);                      \
   }

/* Create a memory pool. */
#define VALGRIND_CREATE_MEMPOOL(pool, rzB, is_zeroed)              \
   {unsigned int _qzz_res;                                         \
    VALGRIND_MAGIC_SEQUENCE(_qzz_res, 0,                           \
                            VG_USERREQ__CREATE_MEMPOOL,            \
                            pool, rzB, is_zeroed, 0);              \
   }

/* Destroy a memory pool. */
#define VALGRIND_DESTROY_MEMPOOL(pool)                             \
   {unsigned int _qzz_res;                                         \
    VALGRIND_MAGIC_SEQUENCE(_qzz_res, 0,                           \
                            VG_USERREQ__DESTROY_MEMPOOL,           \
                            pool, 0, 0, 0);                        \
   }

/* Associate a piece of memory with a memory pool. */
#define VALGRIND_MEMPOOL_ALLOC(pool, addr, size)                   \
   {unsigned int _qzz_res;                                         \
    VALGRIND_MAGIC_SEQUENCE(_qzz_res, 0,                           \
                            VG_USERREQ__MEMPOOL_ALLOC,             \
                            pool, addr, size, 0);                  \
   }

/* Disassociate a piece of memory from a memory pool. */
#define VALGRIND_MEMPOOL_FREE(pool, addr)                          \
   {unsigned int _qzz_res;                                         \
    VALGRIND_MAGIC_SEQUENCE(_qzz_res, 0,                           \
                            VG_USERREQ__MEMPOOL_FREE,              \
                            pool, addr, 0, 0);                     \
   }

/* Mark a piece of memory as being a stack. Returns a stack id. */
#define VALGRIND_STACK_REGISTER(start, end)                        \
   ({unsigned int _qzz_res;                                        \
    VALGRIND_MAGIC_SEQUENCE(_qzz_res, 0,                           \
                            VG_USERREQ__STACK_REGISTER,            \
                            start, end, 0, 0);                     \
    _qzz_res;                                                      \
   })

/* Unmark the piece of memory associated with a stack id as being a
   stack. */
#define VALGRIND_STACK_DEREGISTER(id)                              \
   {unsigned int _qzz_res;                                         \
    VALGRIND_MAGIC_SEQUENCE(_qzz_res, 0,                           \
                            VG_USERREQ__STACK_DEREGISTER,          \
                            id, 0, 0, 0);                          \
   }

/* Change the start and end address of the stack id. */
#define VALGRIND_STACK_CHANGE(id, start, end)                      \
   {unsigned int _qzz_res;                                         \
    VALGRIND_MAGIC_SEQUENCE(_qzz_res, 0,                           \
                            VG_USERREQ__STACK_CHANGE,              \
                            id, start, end, 0);                    \
   }

#endif   /* __VALGRIND_H */