ghelpers.c

The Valgrind distribution has multiple tools. The most popular is the memory checking tool (called M

   { Int cf, pf, af, zf, sf, of;                                \
     DATA_UTYPE  hi;                                            \
     DATA_UTYPE  lo                                             \
        = NARROWtoU( ((DATA_UTYPE)CC_DEP1)                      \
                     * ((DATA_UTYPE)CC_DEP2) );                 \
     DATA_U2TYPE rr                                             \
        = NARROWto2U(                                           \
             ((DATA_U2TYPE)((DATA_UTYPE)CC_DEP1))               \
             * ((DATA_U2TYPE)((DATA_UTYPE)CC_DEP2)) );          \
     hi = NARROWtoU(rr >>/*u*/ DATA_BITS);                      \
     cf = (hi != 0);                                            \
     pf = parity_table[(UChar)lo];                              \
     af = 0; /* undefined */                                    \
     zf = (lo == 0) << 6;                                       \
     sf = lshift(lo, 8 - DATA_BITS) & 0x80;                     \
     of = cf << 11;                                             \
     return cf | pf | af | zf | sf | of;                        \
   }								\
}

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

#define ACTIONS_SMUL(DATA_BITS, DATA_STYPE,  NARROWtoS,         \
                                DATA_S2TYPE, NARROWto2S)        \
{                                                               \
   PREAMBLE(DATA_BITS);                                         \
   { Int cf, pf, af, zf, sf, of;                                \
     DATA_STYPE  hi;                                            \
     DATA_STYPE  lo                                             \
        = NARROWtoS( ((DATA_STYPE)CC_DEP1)                      \
                     * ((DATA_STYPE)CC_DEP2) );                 \
     DATA_S2TYPE rr                                             \
        = NARROWto2S(                                           \
             ((DATA_S2TYPE)((DATA_STYPE)CC_DEP1))               \
             * ((DATA_S2TYPE)((DATA_STYPE)CC_DEP2)) );          \
     hi = NARROWtoS(rr >>/*s*/ DATA_BITS);                      \
     cf = (hi != (lo >>/*s*/ (DATA_BITS-1)));                   \
     pf = parity_table[(UChar)lo];                              \
     af = 0; /* undefined */                                    \
     zf = (lo == 0) << 6;                                       \
     sf = lshift(lo, 8 - DATA_BITS) & 0x80;                     \
     of = cf << 11;                                             \
     return cf | pf | af | zf | sf | of;                        \
   }								\
}


#if PROFILE_EFLAGS

static Bool initted     = False;

/* C flag, fast route */
static UInt tabc_fast[X86G_CC_OP_NUMBER];
/* C flag, slow route */
static UInt tabc_slow[X86G_CC_OP_NUMBER];
/* table for calculate_cond */
static UInt tab_cond[X86G_CC_OP_NUMBER][16];
/* total entry counts for calc_all, calc_c, calc_cond. */
static UInt n_calc_all  = 0;
static UInt n_calc_c    = 0;
static UInt n_calc_cond = 0;

#define SHOW_COUNTS_NOW (0 == (0x3FFFFF & (n_calc_all+n_calc_c+n_calc_cond)))


static void showCounts ( void )
{
   Int op, co;
   Char ch;
   vex_printf("\nTotal calls: calc_all=%u   calc_cond=%u   calc_c=%u\n",
              n_calc_all, n_calc_cond, n_calc_c);

   vex_printf("      cSLOW  cFAST    O   NO    B   NB    Z   NZ   BE  NBE"
              "    S   NS    P   NP    L   NL   LE  NLE\n");
   vex_printf("     -----------------------------------------------------"
              "----------------------------------------\n");
   for (op = 0; op < X86G_CC_OP_NUMBER; op++) {

      ch = ' ';
      if (op > 0 && (op-1) % 3 == 0) 
         ch = 'B';
      if (op > 0 && (op-1) % 3 == 1) 
         ch = 'W';
      if (op > 0 && (op-1) % 3 == 2) 
         ch = 'L';

      vex_printf("%2d%c: ", op, ch);
      vex_printf("%6u ", tabc_slow[op]);
      vex_printf("%6u ", tabc_fast[op]);
      for (co = 0; co < 16; co++) {
         Int n = tab_cond[op][co];
         if (n >= 1000) {
            vex_printf(" %3dK", n / 1000);
         } else 
         if (n >= 0) {
            vex_printf(" %3d ", n );
         } else {
            vex_printf("     ");
         }
      }
      vex_printf("\n");
   }
   vex_printf("\n");
}

static void initCounts ( void )
{
   Int op, co;
   initted = True;
   for (op = 0; op < X86G_CC_OP_NUMBER; op++) {
      tabc_fast[op] = tabc_slow[op] = 0;
      for (co = 0; co < 16; co++)
         tab_cond[op][co] = 0;
   }
}

#endif /* PROFILE_EFLAGS */


/* CALLED FROM GENERATED CODE: CLEAN HELPER */
/* Calculate all the 6 flags from the supplied thunk parameters.
   Worker function, not directly called from generated code. */
static
UInt x86g_calculate_eflags_all_WRK ( UInt cc_op, 
                                     UInt cc_dep1_formal, 
                                     UInt cc_dep2_formal,
                                     UInt cc_ndep_formal )
{
   switch (cc_op) {
      case X86G_CC_OP_COPY:
         return cc_dep1_formal
                & (X86G_CC_MASK_O | X86G_CC_MASK_S | X86G_CC_MASK_Z 
                   | X86G_CC_MASK_A | X86G_CC_MASK_C | X86G_CC_MASK_P);

      case X86G_CC_OP_ADDB:   ACTIONS_ADD( 8,  UChar  );
      case X86G_CC_OP_ADDW:   ACTIONS_ADD( 16, UShort );
      case X86G_CC_OP_ADDL:   ACTIONS_ADD( 32, UInt   );

      case X86G_CC_OP_ADCB:   ACTIONS_ADC( 8,  UChar  );
      case X86G_CC_OP_ADCW:   ACTIONS_ADC( 16, UShort );
      case X86G_CC_OP_ADCL:   ACTIONS_ADC( 32, UInt   );

      case X86G_CC_OP_SUBB:   ACTIONS_SUB(  8, UChar  );
      case X86G_CC_OP_SUBW:   ACTIONS_SUB( 16, UShort );
      case X86G_CC_OP_SUBL:   ACTIONS_SUB( 32, UInt   );

      case X86G_CC_OP_SBBB:   ACTIONS_SBB(  8, UChar  );
      case X86G_CC_OP_SBBW:   ACTIONS_SBB( 16, UShort );
      case X86G_CC_OP_SBBL:   ACTIONS_SBB( 32, UInt   );

      case X86G_CC_OP_LOGICB: ACTIONS_LOGIC(  8, UChar  );
      case X86G_CC_OP_LOGICW: ACTIONS_LOGIC( 16, UShort );
      case X86G_CC_OP_LOGICL: ACTIONS_LOGIC( 32, UInt   );

      case X86G_CC_OP_INCB:   ACTIONS_INC(  8, UChar  );
      case X86G_CC_OP_INCW:   ACTIONS_INC( 16, UShort );
      case X86G_CC_OP_INCL:   ACTIONS_INC( 32, UInt   );

      case X86G_CC_OP_DECB:   ACTIONS_DEC(  8, UChar  );
      case X86G_CC_OP_DECW:   ACTIONS_DEC( 16, UShort );
      case X86G_CC_OP_DECL:   ACTIONS_DEC( 32, UInt   );

      case X86G_CC_OP_SHLB:   ACTIONS_SHL(  8, UChar  );
      case X86G_CC_OP_SHLW:   ACTIONS_SHL( 16, UShort );
      case X86G_CC_OP_SHLL:   ACTIONS_SHL( 32, UInt   );

      case X86G_CC_OP_SHRB:   ACTIONS_SHR(  8, UChar  );
      case X86G_CC_OP_SHRW:   ACTIONS_SHR( 16, UShort );
      case X86G_CC_OP_SHRL:   ACTIONS_SHR( 32, UInt   );

      case X86G_CC_OP_ROLB:   ACTIONS_ROL(  8, UChar  );
      case X86G_CC_OP_ROLW:   ACTIONS_ROL( 16, UShort );
      case X86G_CC_OP_ROLL:   ACTIONS_ROL( 32, UInt   );

      case X86G_CC_OP_RORB:   ACTIONS_ROR(  8, UChar  );
      case X86G_CC_OP_RORW:   ACTIONS_ROR( 16, UShort );
      case X86G_CC_OP_RORL:   ACTIONS_ROR( 32, UInt   );

      case X86G_CC_OP_UMULB:  ACTIONS_UMUL(  8, UChar,  toUChar,
                                                UShort, toUShort );
      case X86G_CC_OP_UMULW:  ACTIONS_UMUL( 16, UShort, toUShort,
                                                UInt,   toUInt );
      case X86G_CC_OP_UMULL:  ACTIONS_UMUL( 32, UInt,   toUInt,
                                                ULong,  idULong );

      case X86G_CC_OP_SMULB:  ACTIONS_SMUL(  8, Char,   toUChar,
                                                Short,  toUShort );
      case X86G_CC_OP_SMULW:  ACTIONS_SMUL( 16, Short,  toUShort, 
                                                Int,    toUInt   );
      case X86G_CC_OP_SMULL:  ACTIONS_SMUL( 32, Int,    toUInt,
                                                Long,   idULong );

      default:
         /* shouldn't really make these calls from generated code */
         vex_printf("x86g_calculate_eflags_all_WRK(X86)"
                    "( %u, 0x%x, 0x%x, 0x%x )\n",
                    cc_op, cc_dep1_formal, cc_dep2_formal, cc_ndep_formal );
         vpanic("x86g_calculate_eflags_all_WRK(X86)");
   }
}


/* CALLED FROM GENERATED CODE: CLEAN HELPER */
/* Calculate all the 6 flags from the supplied thunk parameters. */
UInt x86g_calculate_eflags_all ( UInt cc_op, 
                                 UInt cc_dep1, 
                                 UInt cc_dep2,
                                 UInt cc_ndep )
{
#  if PROFILE_EFLAGS
   if (!initted) initCounts();
   n_calc_all++;
   if (SHOW_COUNTS_NOW) showCounts();
#  endif
   return
      x86g_calculate_eflags_all_WRK ( cc_op, cc_dep1, cc_dep2, cc_ndep );
}


/* CALLED FROM GENERATED CODE: CLEAN HELPER */
/* Calculate just the carry flag from the supplied thunk parameters. */
__attribute((regparm(3)))
UInt x86g_calculate_eflags_c ( UInt cc_op, 
                               UInt cc_dep1, 
                               UInt cc_dep2,
                               UInt cc_ndep )
{
#  if PROFILE_EFLAGS
   if (!initted) initCounts();
   n_calc_c++;
   tabc_fast[cc_op]++;
   if (SHOW_COUNTS_NOW) showCounts();
#  endif

   /* Fast-case some common ones. */
   switch (cc_op) {
      case X86G_CC_OP_LOGICL: 
      case X86G_CC_OP_LOGICW: 
      case X86G_CC_OP_LOGICB:
         return 0;
      case X86G_CC_OP_SUBL:
         return ((UInt)cc_dep1) < ((UInt)cc_dep2)
                   ? X86G_CC_MASK_C : 0;
      case X86G_CC_OP_SUBW:
         return ((UInt)(cc_dep1 & 0xFFFF)) < ((UInt)(cc_dep2 & 0xFFFF))
                   ? X86G_CC_MASK_C : 0;
      case X86G_CC_OP_SUBB:
         return ((UInt)(cc_dep1 & 0xFF)) < ((UInt)(cc_dep2 & 0xFF))
                   ? X86G_CC_MASK_C : 0;
      case X86G_CC_OP_INCL:
      case X86G_CC_OP_DECL:
         return cc_ndep & X86G_CC_MASK_C;
      default: 
         break;
   }

#  if PROFILE_EFLAGS
   tabc_fast[cc_op]--;
   tabc_slow[cc_op]++;
#  endif

   return x86g_calculate_eflags_all_WRK(cc_op,cc_dep1,cc_dep2,cc_ndep) 
          & X86G_CC_MASK_C;
}


/* CALLED FROM GENERATED CODE: CLEAN HELPER */
/* returns 1 or 0 */
UInt x86g_calculate_condition ( UInt/*X86Condcode*/ cond, 
                                UInt cc_op, 
                                UInt cc_dep1, 
                                UInt cc_dep2,
                                UInt cc_ndep )
{
   UInt eflags = x86g_calculate_eflags_all_WRK(cc_op, cc_dep1, 
                                               cc_dep2, cc_ndep);
   UInt of,sf,zf,cf,pf;
   UInt inv = cond & 1;

#  if PROFILE_EFLAGS
   if (!initted) initCounts();
   tab_cond[cc_op][cond]++;
   n_calc_cond++;
   if (SHOW_COUNTS_NOW) showCounts();
#  endif

   switch (cond) {
      case X86CondNO:
      case X86CondO: /* OF == 1 */
         of = eflags >> X86G_CC_SHIFT_O;
         return 1 & (inv ^ of);

      case X86CondNZ:
      case X86CondZ: /* ZF == 1 */
         zf = eflags >> X86G_CC_SHIFT_Z;
         return 1 & (inv ^ zf);

      case X86CondNB:
      case X86CondB: /* CF == 1 */
         cf = eflags >> X86G_CC_SHIFT_C;
         return 1 & (inv ^ cf);
         break;

      case X86CondNBE:
      case X86CondBE: /* (CF or ZF) == 1 */
         cf = eflags >> X86G_CC_SHIFT_C;
         zf = eflags >> X86G_CC_SHIFT_Z;
         return 1 & (inv ^ (cf | zf));
         break;

      case X86CondNS:
      case X86CondS: /* SF == 1 */
         sf = eflags >> X86G_CC_SHIFT_S;
         return 1 & (inv ^ sf);

      case X86CondNP:
      case X86CondP: /* PF == 1 */
         pf = eflags >> X86G_CC_SHIFT_P;
         return 1 & (inv ^ pf);

      case X86CondNL:
      case X86CondL: /* (SF xor OF) == 1 */
         sf = eflags >> X86G_CC_SHIFT_S;
         of = eflags >> X86G_CC_SHIFT_O;
         return 1 & (inv ^ (sf ^ of));
         break;

      case X86CondNLE:
      case X86CondLE: /* ((SF xor OF) or ZF)  == 1 */
         sf = eflags >> X86G_CC_SHIFT_S;
         of = eflags >> X86G_CC_SHIFT_O;
         zf = eflags >> X86G_CC_SHIFT_Z;
         return 1 & (inv ^ ((sf ^ of) | zf));
         break;

      default:
         /* shouldn't really make these calls from generated code */
         vex_printf("x86g_calculate_condition( %u, %u, 0x%x, 0x%x, 0x%x )\n",
                    cond, cc_op, cc_dep1, cc_dep2, cc_ndep );
         vpanic("x86g_calculate_condition");
   }
}


/* VISIBLE TO LIBVEX CLIENT */
UInt LibVEX_GuestX86_get_eflags ( /*IN*/VexGuestX86State* vex_state )
{
   UInt eflags = x86g_calculate_eflags_all_WRK(
                    vex_state->guest_CC_OP,
                    vex_state->guest_CC_DEP1,
                    vex_state->guest_CC_DEP2,
                    vex_state->guest_CC_NDEP
                 );
   UInt dflag = vex_state->guest_DFLAG;
   vassert(dflag == 1 || dflag == 0xFFFFFFFF);
   if (dflag == 0xFFFFFFFF)
      eflags |= (1<<10);
   if (vex_state->guest_IDFLAG == 1)
      eflags |= (1<<21);
   if (vex_state->guest_ACFLAG == 1)
      eflags |= (1<<18);
					     
   return eflags;
}

/* VISIBLE TO LIBVEX CLIENT */
void
LibVEX_GuestX86_put_eflag_c ( UInt new_carry_flag,
                              /*MOD*/VexGuestX86State* vex_state )
{
   UInt oszacp = x86g_calculate_eflags_all_WRK(
                    vex_state->guest_CC_OP,
                    vex_state->guest_CC_DEP1,
                    vex_state->guest_CC_DEP2,
                    vex_state->guest_CC_NDEP
                 );
   if (new_carry_flag & 1) {
      oszacp |= X86G_CC_MASK_C;
   } else {
      oszacp &= ~X86G_CC_MASK_C;