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) 2004-2013 OpenWorks LLP
11       info@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 #include "libvex_basictypes.h"
42 #include "libvex_guest_x86.h"           // VexGuestX86State
43 #include "libvex_emnote.h"              // VexEmNote
44 #include "guest_generic_bb_to_IR.h"     // DisResult
45 
46 /*---------------------------------------------------------*/
47 /*--- x86 to IR conversion                              ---*/
48 /*---------------------------------------------------------*/
49 
50 /* Convert one x86 insn to IR.  See the type DisOneInstrFn in
51    bb_to_IR.h. */
52 extern
53 DisResult disInstr_X86 ( IRSB*        irbb,
54                          Bool         (*resteerOkFn) ( void*, Addr ),
55                          Bool         resteerCisOk,
56                          void*        callback_opaque,
57                          const UChar* guest_code,
58                          Long         delta,
59                          Addr         guest_IP,
60                          VexArch      guest_arch,
61                          const VexArchInfo* archinfo,
62                          const VexAbiInfo*  abiinfo,
63                          VexEndness   host_endness,
64                          Bool         sigill_diag );
65 
66 /* Used by the optimiser to specialise calls to helpers. */
67 extern
68 IRExpr* guest_x86_spechelper ( const HChar* function_name,
69                                IRExpr** args,
70                                IRStmt** precedingStmts,
71                                Int      n_precedingStmts );
72 
73 /* Describes to the optimiser which part of the guest state require
74    precise memory exceptions.  This is logically part of the guest
75    state description. */
76 extern
77 Bool guest_x86_state_requires_precise_mem_exns ( Int, Int,
78                                                  VexRegisterUpdates );
79 
80 extern
81 VexGuestLayout x86guest_layout;
82 
83 
84 /*---------------------------------------------------------*/
85 /*--- x86 guest helpers                                 ---*/
86 /*---------------------------------------------------------*/
87 
88 /* --- CLEAN HELPERS --- */
89 
90 extern UInt  x86g_calculate_eflags_all (
91                 UInt cc_op, UInt cc_dep1, UInt cc_dep2, UInt cc_ndep
92              );
93 
94 VEX_REGPARM(3)
95 extern UInt  x86g_calculate_eflags_c (
96                 UInt cc_op, UInt cc_dep1, UInt cc_dep2, UInt cc_ndep
97              );
98 
99 extern UInt  x86g_calculate_condition (
100                 UInt/*X86Condcode*/ cond,
101                 UInt cc_op,
102                 UInt cc_dep1, UInt cc_dep2, UInt cc_ndep
103              );
104 
105 extern UInt  x86g_calculate_FXAM ( UInt tag, ULong dbl );
106 
107 extern ULong x86g_calculate_RCR (
108                 UInt arg, UInt rot_amt, UInt eflags_in, UInt sz
109              );
110 extern ULong x86g_calculate_RCL (
111                 UInt arg, UInt rot_amt, UInt eflags_in, UInt sz
112              );
113 
114 extern UInt x86g_calculate_daa_das_aaa_aas ( UInt AX_and_flags, UInt opcode );
115 
116 extern UInt x86g_calculate_aad_aam ( UInt AX_and_flags, UInt opcode );
117 
118 extern ULong x86g_check_fldcw ( UInt fpucw );
119 
120 extern UInt  x86g_create_fpucw ( UInt fpround );
121 
122 extern ULong x86g_check_ldmxcsr ( UInt mxcsr );
123 
124 extern UInt  x86g_create_mxcsr ( UInt sseround );
125 
126 
127 /* Translate a guest virtual_addr into a guest linear address by
128    consulting the supplied LDT/GDT structures.  Their representation
129    must be as specified in pub/libvex_guest_x86.h.  To indicate a
130    translation failure, 1<<32 is returned.  On success, the lower 32
131    bits of the returned result indicate the linear address.
132 */
133 extern
134 ULong x86g_use_seg_selector ( HWord ldt, HWord gdt,
135                               UInt seg_selector, UInt virtual_addr );
136 
137 extern ULong x86g_calculate_mmx_pmaddwd  ( ULong, ULong );
138 extern ULong x86g_calculate_mmx_psadbw   ( ULong, ULong );
139 
140 
141 /* --- DIRTY HELPERS --- */
142 
143 extern ULong x86g_dirtyhelper_loadF80le  ( Addr );
144 
145 extern void  x86g_dirtyhelper_storeF80le ( Addr, ULong );
146 
147 extern void  x86g_dirtyhelper_CPUID_sse0 ( VexGuestX86State* );
148 extern void  x86g_dirtyhelper_CPUID_mmxext ( VexGuestX86State* );
149 extern void  x86g_dirtyhelper_CPUID_sse1 ( VexGuestX86State* );
150 extern void  x86g_dirtyhelper_CPUID_sse2 ( VexGuestX86State* );
151 
152 extern void  x86g_dirtyhelper_FINIT ( VexGuestX86State* );
153 
154 extern void  x86g_dirtyhelper_FXSAVE ( VexGuestX86State*, HWord );
155 extern void  x86g_dirtyhelper_FSAVE  ( VexGuestX86State*, HWord );
156 extern void  x86g_dirtyhelper_FSTENV ( VexGuestX86State*, HWord );
157 
158 extern ULong x86g_dirtyhelper_RDTSC ( void );
159 
160 extern UInt x86g_dirtyhelper_IN  ( UInt portno, UInt sz/*1,2 or 4*/ );
161 extern void x86g_dirtyhelper_OUT ( UInt portno, UInt data,
162                                    UInt sz/*1,2 or 4*/ );
163 
164 extern void x86g_dirtyhelper_SxDT ( void* address,
165                                     UInt op /* 0 or 1 */ );
166 
167 extern VexEmNote
168             x86g_dirtyhelper_FXRSTOR ( VexGuestX86State*, HWord );
169 
170 extern VexEmNote
171             x86g_dirtyhelper_FRSTOR ( VexGuestX86State*, HWord );
172 
173 extern VexEmNote
174             x86g_dirtyhelper_FLDENV ( VexGuestX86State*, HWord );
175 
176 
177 /*---------------------------------------------------------*/
178 /*--- Condition code stuff                              ---*/
179 /*---------------------------------------------------------*/
180 
181 /* eflags masks */
182 #define X86G_CC_SHIFT_O   11
183 #define X86G_CC_SHIFT_S   7
184 #define X86G_CC_SHIFT_Z   6
185 #define X86G_CC_SHIFT_A   4
186 #define X86G_CC_SHIFT_C   0
187 #define X86G_CC_SHIFT_P   2
188 
189 #define X86G_CC_MASK_O    (1 << X86G_CC_SHIFT_O)
190 #define X86G_CC_MASK_S    (1 << X86G_CC_SHIFT_S)
191 #define X86G_CC_MASK_Z    (1 << X86G_CC_SHIFT_Z)
192 #define X86G_CC_MASK_A    (1 << X86G_CC_SHIFT_A)
193 #define X86G_CC_MASK_C    (1 << X86G_CC_SHIFT_C)
194 #define X86G_CC_MASK_P    (1 << X86G_CC_SHIFT_P)
195 
196 /* FPU flag masks */
197 #define X86G_FC_SHIFT_C3   14
198 #define X86G_FC_SHIFT_C2   10
199 #define X86G_FC_SHIFT_C1   9
200 #define X86G_FC_SHIFT_C0   8
201 
202 #define X86G_FC_MASK_C3    (1 << X86G_FC_SHIFT_C3)
203 #define X86G_FC_MASK_C2    (1 << X86G_FC_SHIFT_C2)
204 #define X86G_FC_MASK_C1    (1 << X86G_FC_SHIFT_C1)
205 #define X86G_FC_MASK_C0    (1 << X86G_FC_SHIFT_C0)
206 
207 
208 /* %EFLAGS thunk descriptors.  A four-word thunk is used to record
209    details of the most recent flag-setting operation, so the flags can
210    be computed later if needed.  It is possible to do this a little
211    more efficiently using a 3-word thunk, but that makes it impossible
212    to describe the flag data dependencies sufficiently accurately for
213    Memcheck.  Hence 4 words are used, with minimal loss of efficiency.
214 
215    The four words are:
216 
217       CC_OP, which describes the operation.
218 
219       CC_DEP1 and CC_DEP2.  These are arguments to the operation.
220          We want Memcheck to believe that the resulting flags are
221          data-dependent on both CC_DEP1 and CC_DEP2, hence the
222          name DEP.
223 
224       CC_NDEP.  This is a 3rd argument to the operation which is
225          sometimes needed.  We arrange things so that Memcheck does
226          not believe the resulting flags are data-dependent on CC_NDEP
227          ("not dependent").
228 
229    To make Memcheck believe that (the definedness of) the encoded
230    flags depends only on (the definedness of) CC_DEP1 and CC_DEP2
231    requires two things:
232 
233    (1) In the guest state layout info (x86guest_layout), CC_OP and
234        CC_NDEP are marked as always defined.
235 
236    (2) When passing the thunk components to an evaluation function
237        (calculate_condition, calculate_eflags, calculate_eflags_c) the
238        IRCallee's mcx_mask must be set so as to exclude from
239        consideration all passed args except CC_DEP1 and CC_DEP2.
240 
241    Strictly speaking only (2) is necessary for correctness.  However,
242    (1) helps efficiency in that since (2) means we never ask about the
243    definedness of CC_OP or CC_NDEP, we may as well not even bother to
244    track their definedness.
245 
246    When building the thunk, it is always necessary to write words into
247    CC_DEP1 and CC_DEP2, even if those args are not used given the
248    CC_OP field (eg, CC_DEP2 is not used if CC_OP is CC_LOGIC1/2/4).
249    This is important because otherwise Memcheck could give false
250    positives as it does not understand the relationship between the
251    CC_OP field and CC_DEP1 and CC_DEP2, and so believes that the
252    definedness of the stored flags always depends on both CC_DEP1 and
253    CC_DEP2.
254 
255    However, it is only necessary to set CC_NDEP when the CC_OP value
256    requires it, because Memcheck ignores CC_NDEP, and the evaluation
257    functions do understand the CC_OP fields and will only examine
258    CC_NDEP for suitable values of CC_OP.
259 
260    A summary of the field usages is:
261 
262    Operation          DEP1               DEP2               NDEP
263    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
264 
265    add/sub/mul        first arg          second arg         unused
266 
267    adc/sbb            first arg          (second arg)
268                                          XOR old_carry      old_carry
269 
270    and/or/xor         result             zero               unused
271 
272    inc/dec            result             zero               old_carry
273 
274    shl/shr/sar        result             subshifted-        unused
275                                          result
276 
277    rol/ror            result             zero               old_flags
278 
279    copy               old_flags          zero               unused.
280 
281 
282    Therefore Memcheck will believe the following:
283 
284    * add/sub/mul -- definedness of result flags depends on definedness
285      of both args.
286 
287    * adc/sbb -- definedness of result flags depends on definedness of
288      both args and definedness of the old C flag.  Because only two
289      DEP fields are available, the old C flag is XOR'd into the second
290      arg so that Memcheck sees the data dependency on it.  That means
291      the NDEP field must contain a second copy of the old C flag
292      so that the evaluation functions can correctly recover the second
293      arg.
294 
295    * and/or/xor are straightforward -- definedness of result flags
296      depends on definedness of result value.
297 
298    * inc/dec -- definedness of result flags depends only on
299      definedness of result.  This isn't really true -- it also depends
300      on the old C flag.  However, we don't want Memcheck to see that,
301      and so the old C flag must be passed in NDEP and not in DEP2.
302      It's inconceivable that a compiler would generate code that puts
303      the C flag in an undefined state, then does an inc/dec, which
304      leaves C unchanged, and then makes a conditional jump/move based
305      on C.  So our fiction seems a good approximation.
306 
307    * shl/shr/sar -- straightforward, again, definedness of result
308      flags depends on definedness of result value.  The subshifted
309      value (value shifted one less) is also needed, but its
310      definedness is the same as the definedness of the shifted value.
311 
312    * rol/ror -- these only set O and C, and leave A Z C P alone.
313      However it seems prudent (as per inc/dec) to say the definedness
314      of all resulting flags depends on the definedness of the result,
315      hence the old flags must go in as NDEP and not DEP2.
316 
317    * rcl/rcr are too difficult to do in-line, and so are done by a
318      helper function.  They are not part of this scheme.  The helper
319      function takes the value to be rotated, the rotate amount and the
320      old flags, and returns the new flags and the rotated value.
321      Since the helper's mcx_mask does not have any set bits, Memcheck
322      will lazily propagate undefinedness from any of the 3 args into
323      both results (flags and actual value).
324 */
325 enum {
326     X86G_CC_OP_COPY=0,  /* DEP1 = current flags, DEP2 = 0, NDEP = unused */
327                         /* just copy DEP1 to output */
328 
329     X86G_CC_OP_ADDB,    /* 1 */
330     X86G_CC_OP_ADDW,    /* 2 DEP1 = argL, DEP2 = argR, NDEP = unused */
331     X86G_CC_OP_ADDL,    /* 3 */
332 
333     X86G_CC_OP_SUBB,    /* 4 */
334     X86G_CC_OP_SUBW,    /* 5 DEP1 = argL, DEP2 = argR, NDEP = unused */
335     X86G_CC_OP_SUBL,    /* 6 */
336 
337     X86G_CC_OP_ADCB,    /* 7 */
338     X86G_CC_OP_ADCW,    /* 8 DEP1 = argL, DEP2 = argR ^ oldCarry, NDEP = oldCarry */
339     X86G_CC_OP_ADCL,    /* 9 */
340 
341     X86G_CC_OP_SBBB,    /* 10 */
342     X86G_CC_OP_SBBW,    /* 11 DEP1 = argL, DEP2 = argR ^ oldCarry, NDEP = oldCarry */
343     X86G_CC_OP_SBBL,    /* 12 */
344 
345     X86G_CC_OP_LOGICB,  /* 13 */
346     X86G_CC_OP_LOGICW,  /* 14 DEP1 = result, DEP2 = 0, NDEP = unused */
347     X86G_CC_OP_LOGICL,  /* 15 */
348 
349     X86G_CC_OP_INCB,    /* 16 */
350     X86G_CC_OP_INCW,    /* 17 DEP1 = result, DEP2 = 0, NDEP = oldCarry (0 or 1) */
351     X86G_CC_OP_INCL,    /* 18 */
352 
353     X86G_CC_OP_DECB,    /* 19 */
354     X86G_CC_OP_DECW,    /* 20 DEP1 = result, DEP2 = 0, NDEP = oldCarry (0 or 1) */
355     X86G_CC_OP_DECL,    /* 21 */
356 
357     X86G_CC_OP_SHLB,    /* 22 DEP1 = res, DEP2 = res', NDEP = unused */
358     X86G_CC_OP_SHLW,    /* 23 where res' is like res but shifted one bit less */
359     X86G_CC_OP_SHLL,    /* 24 */
360 
361     X86G_CC_OP_SHRB,    /* 25 DEP1 = res, DEP2 = res', NDEP = unused */
362     X86G_CC_OP_SHRW,    /* 26 where res' is like res but shifted one bit less */
363     X86G_CC_OP_SHRL,    /* 27 */
364 
365     X86G_CC_OP_ROLB,    /* 28 */
366     X86G_CC_OP_ROLW,    /* 29 DEP1 = res, DEP2 = 0, NDEP = old flags */
367     X86G_CC_OP_ROLL,    /* 30 */
368 
369     X86G_CC_OP_RORB,    /* 31 */
370     X86G_CC_OP_RORW,    /* 32 DEP1 = res, DEP2 = 0, NDEP = old flags */
371     X86G_CC_OP_RORL,    /* 33 */
372 
373     X86G_CC_OP_UMULB,   /* 34 */
374     X86G_CC_OP_UMULW,   /* 35 DEP1 = argL, DEP2 = argR, NDEP = unused */
375     X86G_CC_OP_UMULL,   /* 36 */
376 
377     X86G_CC_OP_SMULB,   /* 37 */
378     X86G_CC_OP_SMULW,   /* 38 DEP1 = argL, DEP2 = argR, NDEP = unused */
379     X86G_CC_OP_SMULL,   /* 39 */
380 
381     X86G_CC_OP_NUMBER
382 };
383 
384 typedef
385    enum {
386       X86CondO      = 0,  /* overflow           */
387       X86CondNO     = 1,  /* no overflow        */
388 
389       X86CondB      = 2,  /* below              */
390       X86CondNB     = 3,  /* not below          */
391 
392       X86CondZ      = 4,  /* zero               */
393       X86CondNZ     = 5,  /* not zero           */
394 
395       X86CondBE     = 6,  /* below or equal     */
396       X86CondNBE    = 7,  /* not below or equal */
397 
398       X86CondS      = 8,  /* negative           */
399       X86CondNS     = 9,  /* not negative       */
400 
401       X86CondP      = 10, /* parity even        */
402       X86CondNP     = 11, /* not parity even    */
403 
404       X86CondL      = 12, /* jump less          */
405       X86CondNL     = 13, /* not less           */
406 
407       X86CondLE     = 14, /* less or equal      */
408       X86CondNLE    = 15, /* not less or equal  */
409 
410       X86CondAlways = 16  /* HACK */
411    }
412    X86Condcode;
413 
414 #endif /* ndef __VEX_GUEST_X86_DEFS_H */
415 
416 /*---------------------------------------------------------------*/
417 /*--- end                                    guest_x86_defs.h ---*/
418 /*---------------------------------------------------------------*/
419