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      1 
      2 /*---------------------------------------------------------------*/
      3 /*--- begin                                  guest_x86_defs.h ---*/
      4 /*---------------------------------------------------------------*/
      5 
      6 /*
      7    This file is part of Valgrind, a dynamic binary instrumentation
      8    framework.
      9 
     10    Copyright (C) 2004-2012 OpenWorks LLP
     11       info (at) open-works.net
     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., 51 Franklin Street, Fifth Floor, Boston, MA
     26    02110-1301, USA.
     27 
     28    The GNU General Public License is contained in the file COPYING.
     29 
     30    Neither the names of the U.S. Department of Energy nor the
     31    University of California nor the names of its contributors may be
     32    used to endorse or promote products derived from this software
     33    without prior written permission.
     34 */
     35 
     36 /* Only to be used within the guest-x86 directory. */
     37 
     38 #ifndef __VEX_GUEST_X86_DEFS_H
     39 #define __VEX_GUEST_X86_DEFS_H
     40 
     41 
     42 /*---------------------------------------------------------*/
     43 /*--- x86 to IR conversion                              ---*/
     44 /*---------------------------------------------------------*/
     45 
     46 /* Convert one x86 insn to IR.  See the type DisOneInstrFn in
     47    bb_to_IR.h. */
     48 extern
     49 DisResult disInstr_X86 ( IRSB*        irbb,
     50                          Bool         (*resteerOkFn) ( void*, Addr64 ),
     51                          Bool         resteerCisOk,
     52                          void*        callback_opaque,
     53                          UChar*       guest_code,
     54                          Long         delta,
     55                          Addr64       guest_IP,
     56                          VexArch      guest_arch,
     57                          VexArchInfo* archinfo,
     58                          VexAbiInfo*  abiinfo,
     59                          Bool         host_bigendian );
     60 
     61 /* Used by the optimiser to specialise calls to helpers. */
     62 extern
     63 IRExpr* guest_x86_spechelper ( HChar*   function_name,
     64                                IRExpr** args,
     65                                IRStmt** precedingStmts,
     66                                Int      n_precedingStmts );
     67 
     68 /* Describes to the optimiser which part of the guest state require
     69    precise memory exceptions.  This is logically part of the guest
     70    state description. */
     71 extern
     72 Bool guest_x86_state_requires_precise_mem_exns ( Int, Int );
     73 
     74 extern
     75 VexGuestLayout x86guest_layout;
     76 
     77 
     78 /*---------------------------------------------------------*/
     79 /*--- x86 guest helpers                                 ---*/
     80 /*---------------------------------------------------------*/
     81 
     82 /* --- CLEAN HELPERS --- */
     83 
     84 extern UInt  x86g_calculate_eflags_all (
     85                 UInt cc_op, UInt cc_dep1, UInt cc_dep2, UInt cc_ndep
     86              );
     87 
     88 VEX_REGPARM(3)
     89 extern UInt  x86g_calculate_eflags_c (
     90                 UInt cc_op, UInt cc_dep1, UInt cc_dep2, UInt cc_ndep
     91              );
     92 
     93 extern UInt  x86g_calculate_condition (
     94                 UInt/*X86Condcode*/ cond,
     95                 UInt cc_op,
     96                 UInt cc_dep1, UInt cc_dep2, UInt cc_ndep
     97              );
     98 
     99 extern UInt  x86g_calculate_FXAM ( UInt tag, ULong dbl );
    100 
    101 extern ULong x86g_calculate_RCR (
    102                 UInt arg, UInt rot_amt, UInt eflags_in, UInt sz
    103              );
    104 extern ULong x86g_calculate_RCL (
    105                 UInt arg, UInt rot_amt, UInt eflags_in, UInt sz
    106              );
    107 
    108 extern UInt x86g_calculate_daa_das_aaa_aas ( UInt AX_and_flags, UInt opcode );
    109 
    110 extern UInt x86g_calculate_aad_aam ( UInt AX_and_flags, UInt opcode );
    111 
    112 extern ULong x86g_check_fldcw ( UInt fpucw );
    113 
    114 extern UInt  x86g_create_fpucw ( UInt fpround );
    115 
    116 extern ULong x86g_check_ldmxcsr ( UInt mxcsr );
    117 
    118 extern UInt  x86g_create_mxcsr ( UInt sseround );
    119 
    120 
    121 /* Translate a guest virtual_addr into a guest linear address by
    122    consulting the supplied LDT/GDT structures.  Their representation
    123    must be as specified in pub/libvex_guest_x86.h.  To indicate a
    124    translation failure, 1<<32 is returned.  On success, the lower 32
    125    bits of the returned result indicate the linear address.
    126 */
    127 extern
    128 ULong x86g_use_seg_selector ( HWord ldt, HWord gdt,
    129                               UInt seg_selector, UInt virtual_addr );
    130 
    131 extern ULong x86g_calculate_mmx_pmaddwd  ( ULong, ULong );
    132 extern ULong x86g_calculate_mmx_psadbw   ( ULong, ULong );
    133 extern UInt  x86g_calculate_mmx_pmovmskb ( ULong );
    134 extern UInt  x86g_calculate_sse_pmovmskb ( ULong w64hi, ULong w64lo );
    135 
    136 
    137 /* --- DIRTY HELPERS --- */
    138 
    139 extern ULong x86g_dirtyhelper_loadF80le  ( UInt );
    140 
    141 extern void  x86g_dirtyhelper_storeF80le ( UInt, ULong );
    142 
    143 extern void  x86g_dirtyhelper_CPUID_sse0 ( VexGuestX86State* );
    144 extern void  x86g_dirtyhelper_CPUID_sse1 ( VexGuestX86State* );
    145 extern void  x86g_dirtyhelper_CPUID_sse2 ( VexGuestX86State* );
    146 
    147 extern void  x86g_dirtyhelper_FINIT ( VexGuestX86State* );
    148 
    149 extern void  x86g_dirtyhelper_FXSAVE ( VexGuestX86State*, HWord );
    150 extern void  x86g_dirtyhelper_FSAVE  ( VexGuestX86State*, HWord );
    151 extern void  x86g_dirtyhelper_FSTENV ( VexGuestX86State*, HWord );
    152 
    153 extern ULong x86g_dirtyhelper_RDTSC ( void );
    154 
    155 extern UInt x86g_dirtyhelper_IN  ( UInt portno, UInt sz/*1,2 or 4*/ );
    156 extern void x86g_dirtyhelper_OUT ( UInt portno, UInt data,
    157                                    UInt sz/*1,2 or 4*/ );
    158 
    159 extern void x86g_dirtyhelper_SxDT ( void* address,
    160                                     UInt op /* 0 or 1 */ );
    161 
    162 extern VexEmWarn
    163             x86g_dirtyhelper_FXRSTOR ( VexGuestX86State*, HWord );
    164 
    165 extern VexEmWarn
    166             x86g_dirtyhelper_FRSTOR ( VexGuestX86State*, HWord );
    167 
    168 extern VexEmWarn
    169             x86g_dirtyhelper_FLDENV ( VexGuestX86State*, HWord );
    170 
    171 
    172 /*---------------------------------------------------------*/
    173 /*--- Condition code stuff                              ---*/
    174 /*---------------------------------------------------------*/
    175 
    176 /* eflags masks */
    177 #define X86G_CC_SHIFT_O   11
    178 #define X86G_CC_SHIFT_S   7
    179 #define X86G_CC_SHIFT_Z   6
    180 #define X86G_CC_SHIFT_A   4
    181 #define X86G_CC_SHIFT_C   0
    182 #define X86G_CC_SHIFT_P   2
    183 
    184 #define X86G_CC_MASK_O    (1 << X86G_CC_SHIFT_O)
    185 #define X86G_CC_MASK_S    (1 << X86G_CC_SHIFT_S)
    186 #define X86G_CC_MASK_Z    (1 << X86G_CC_SHIFT_Z)
    187 #define X86G_CC_MASK_A    (1 << X86G_CC_SHIFT_A)
    188 #define X86G_CC_MASK_C    (1 << X86G_CC_SHIFT_C)
    189 #define X86G_CC_MASK_P    (1 << X86G_CC_SHIFT_P)
    190 
    191 /* FPU flag masks */
    192 #define X86G_FC_SHIFT_C3   14
    193 #define X86G_FC_SHIFT_C2   10
    194 #define X86G_FC_SHIFT_C1   9
    195 #define X86G_FC_SHIFT_C0   8
    196 
    197 #define X86G_FC_MASK_C3    (1 << X86G_FC_SHIFT_C3)
    198 #define X86G_FC_MASK_C2    (1 << X86G_FC_SHIFT_C2)
    199 #define X86G_FC_MASK_C1    (1 << X86G_FC_SHIFT_C1)
    200 #define X86G_FC_MASK_C0    (1 << X86G_FC_SHIFT_C0)
    201 
    202 
    203 /* %EFLAGS thunk descriptors.  A four-word thunk is used to record
    204    details of the most recent flag-setting operation, so the flags can
    205    be computed later if needed.  It is possible to do this a little
    206    more efficiently using a 3-word thunk, but that makes it impossible
    207    to describe the flag data dependencies sufficiently accurately for
    208    Memcheck.  Hence 4 words are used, with minimal loss of efficiency.
    209 
    210    The four words are:
    211 
    212       CC_OP, which describes the operation.
    213 
    214       CC_DEP1 and CC_DEP2.  These are arguments to the operation.
    215          We want Memcheck to believe that the resulting flags are
    216          data-dependent on both CC_DEP1 and CC_DEP2, hence the
    217          name DEP.
    218 
    219       CC_NDEP.  This is a 3rd argument to the operation which is
    220          sometimes needed.  We arrange things so that Memcheck does
    221          not believe the resulting flags are data-dependent on CC_NDEP
    222          ("not dependent").
    223 
    224    To make Memcheck believe that (the definedness of) the encoded
    225    flags depends only on (the definedness of) CC_DEP1 and CC_DEP2
    226    requires two things:
    227 
    228    (1) In the guest state layout info (x86guest_layout), CC_OP and
    229        CC_NDEP are marked as always defined.
    230 
    231    (2) When passing the thunk components to an evaluation function
    232        (calculate_condition, calculate_eflags, calculate_eflags_c) the
    233        IRCallee's mcx_mask must be set so as to exclude from
    234        consideration all passed args except CC_DEP1 and CC_DEP2.
    235 
    236    Strictly speaking only (2) is necessary for correctness.  However,
    237    (1) helps efficiency in that since (2) means we never ask about the
    238    definedness of CC_OP or CC_NDEP, we may as well not even bother to
    239    track their definedness.
    240 
    241    When building the thunk, it is always necessary to write words into
    242    CC_DEP1 and CC_DEP2, even if those args are not used given the
    243    CC_OP field (eg, CC_DEP2 is not used if CC_OP is CC_LOGIC1/2/4).
    244    This is important because otherwise Memcheck could give false
    245    positives as it does not understand the relationship between the
    246    CC_OP field and CC_DEP1 and CC_DEP2, and so believes that the
    247    definedness of the stored flags always depends on both CC_DEP1 and
    248    CC_DEP2.
    249 
    250    However, it is only necessary to set CC_NDEP when the CC_OP value
    251    requires it, because Memcheck ignores CC_NDEP, and the evaluation
    252    functions do understand the CC_OP fields and will only examine
    253    CC_NDEP for suitable values of CC_OP.
    254 
    255    A summary of the field usages is:
    256 
    257    Operation          DEP1               DEP2               NDEP
    258    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    259 
    260    add/sub/mul        first arg          second arg         unused
    261 
    262    adc/sbb            first arg          (second arg)
    263                                          XOR old_carry      old_carry
    264 
    265    and/or/xor         result             zero               unused
    266 
    267    inc/dec            result             zero               old_carry
    268 
    269    shl/shr/sar        result             subshifted-        unused
    270                                          result
    271 
    272    rol/ror            result             zero               old_flags
    273 
    274    copy               old_flags          zero               unused.
    275 
    276 
    277    Therefore Memcheck will believe the following:
    278 
    279    * add/sub/mul -- definedness of result flags depends on definedness
    280      of both args.
    281 
    282    * adc/sbb -- definedness of result flags depends on definedness of
    283      both args and definedness of the old C flag.  Because only two
    284      DEP fields are available, the old C flag is XOR'd into the second
    285      arg so that Memcheck sees the data dependency on it.  That means
    286      the NDEP field must contain a second copy of the old C flag
    287      so that the evaluation functions can correctly recover the second
    288      arg.
    289 
    290    * and/or/xor are straightforward -- definedness of result flags
    291      depends on definedness of result value.
    292 
    293    * inc/dec -- definedness of result flags depends only on
    294      definedness of result.  This isn't really true -- it also depends
    295      on the old C flag.  However, we don't want Memcheck to see that,
    296      and so the old C flag must be passed in NDEP and not in DEP2.
    297      It's inconceivable that a compiler would generate code that puts
    298      the C flag in an undefined state, then does an inc/dec, which
    299      leaves C unchanged, and then makes a conditional jump/move based
    300      on C.  So our fiction seems a good approximation.
    301 
    302    * shl/shr/sar -- straightforward, again, definedness of result
    303      flags depends on definedness of result value.  The subshifted
    304      value (value shifted one less) is also needed, but its
    305      definedness is the same as the definedness of the shifted value.
    306 
    307    * rol/ror -- these only set O and C, and leave A Z C P alone.
    308      However it seems prudent (as per inc/dec) to say the definedness
    309      of all resulting flags depends on the definedness of the result,
    310      hence the old flags must go in as NDEP and not DEP2.
    311 
    312    * rcl/rcr are too difficult to do in-line, and so are done by a
    313      helper function.  They are not part of this scheme.  The helper
    314      function takes the value to be rotated, the rotate amount and the
    315      old flags, and returns the new flags and the rotated value.
    316      Since the helper's mcx_mask does not have any set bits, Memcheck
    317      will lazily propagate undefinedness from any of the 3 args into
    318      both results (flags and actual value).
    319 */
    320 enum {
    321     X86G_CC_OP_COPY=0,  /* DEP1 = current flags, DEP2 = 0, NDEP = unused */
    322                         /* just copy DEP1 to output */
    323 
    324     X86G_CC_OP_ADDB,    /* 1 */
    325     X86G_CC_OP_ADDW,    /* 2 DEP1 = argL, DEP2 = argR, NDEP = unused */
    326     X86G_CC_OP_ADDL,    /* 3 */
    327 
    328     X86G_CC_OP_SUBB,    /* 4 */
    329     X86G_CC_OP_SUBW,    /* 5 DEP1 = argL, DEP2 = argR, NDEP = unused */
    330     X86G_CC_OP_SUBL,    /* 6 */
    331 
    332     X86G_CC_OP_ADCB,    /* 7 */
    333     X86G_CC_OP_ADCW,    /* 8 DEP1 = argL, DEP2 = argR ^ oldCarry, NDEP = oldCarry */
    334     X86G_CC_OP_ADCL,    /* 9 */
    335 
    336     X86G_CC_OP_SBBB,    /* 10 */
    337     X86G_CC_OP_SBBW,    /* 11 DEP1 = argL, DEP2 = argR ^ oldCarry, NDEP = oldCarry */
    338     X86G_CC_OP_SBBL,    /* 12 */
    339 
    340     X86G_CC_OP_LOGICB,  /* 13 */
    341     X86G_CC_OP_LOGICW,  /* 14 DEP1 = result, DEP2 = 0, NDEP = unused */
    342     X86G_CC_OP_LOGICL,  /* 15 */
    343 
    344     X86G_CC_OP_INCB,    /* 16 */
    345     X86G_CC_OP_INCW,    /* 17 DEP1 = result, DEP2 = 0, NDEP = oldCarry (0 or 1) */
    346     X86G_CC_OP_INCL,    /* 18 */
    347 
    348     X86G_CC_OP_DECB,    /* 19 */
    349     X86G_CC_OP_DECW,    /* 20 DEP1 = result, DEP2 = 0, NDEP = oldCarry (0 or 1) */
    350     X86G_CC_OP_DECL,    /* 21 */
    351 
    352     X86G_CC_OP_SHLB,    /* 22 DEP1 = res, DEP2 = res', NDEP = unused */
    353     X86G_CC_OP_SHLW,    /* 23 where res' is like res but shifted one bit less */
    354     X86G_CC_OP_SHLL,    /* 24 */
    355 
    356     X86G_CC_OP_SHRB,    /* 25 DEP1 = res, DEP2 = res', NDEP = unused */
    357     X86G_CC_OP_SHRW,    /* 26 where res' is like res but shifted one bit less */
    358     X86G_CC_OP_SHRL,    /* 27 */
    359 
    360     X86G_CC_OP_ROLB,    /* 28 */
    361     X86G_CC_OP_ROLW,    /* 29 DEP1 = res, DEP2 = 0, NDEP = old flags */
    362     X86G_CC_OP_ROLL,    /* 30 */
    363 
    364     X86G_CC_OP_RORB,    /* 31 */
    365     X86G_CC_OP_RORW,    /* 32 DEP1 = res, DEP2 = 0, NDEP = old flags */
    366     X86G_CC_OP_RORL,    /* 33 */
    367 
    368     X86G_CC_OP_UMULB,   /* 34 */
    369     X86G_CC_OP_UMULW,   /* 35 DEP1 = argL, DEP2 = argR, NDEP = unused */
    370     X86G_CC_OP_UMULL,   /* 36 */
    371 
    372     X86G_CC_OP_SMULB,   /* 37 */
    373     X86G_CC_OP_SMULW,   /* 38 DEP1 = argL, DEP2 = argR, NDEP = unused */
    374     X86G_CC_OP_SMULL,   /* 39 */
    375 
    376     X86G_CC_OP_NUMBER
    377 };
    378 
    379 typedef
    380    enum {
    381       X86CondO      = 0,  /* overflow           */
    382       X86CondNO     = 1,  /* no overflow        */
    383 
    384       X86CondB      = 2,  /* below              */
    385       X86CondNB     = 3,  /* not below          */
    386 
    387       X86CondZ      = 4,  /* zero               */
    388       X86CondNZ     = 5,  /* not zero           */
    389 
    390       X86CondBE     = 6,  /* below or equal     */
    391       X86CondNBE    = 7,  /* not below or equal */
    392 
    393       X86CondS      = 8,  /* negative           */
    394       X86CondNS     = 9,  /* not negative       */
    395 
    396       X86CondP      = 10, /* parity even        */
    397       X86CondNP     = 11, /* not parity even    */
    398 
    399       X86CondL      = 12, /* jump less          */
    400       X86CondNL     = 13, /* not less           */
    401 
    402       X86CondLE     = 14, /* less or equal      */
    403       X86CondNLE    = 15, /* not less or equal  */
    404 
    405       X86CondAlways = 16  /* HACK */
    406    }
    407    X86Condcode;
    408 
    409 #endif /* ndef __VEX_GUEST_X86_DEFS_H */
    410 
    411 /*---------------------------------------------------------------*/
    412 /*--- end                                    guest_x86_defs.h ---*/
    413 /*---------------------------------------------------------------*/
    414