toir.c

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

     = { "%rax", "%rcx", "%rdx", "%rbx", "%rsp", "%rbp", "%rsi", "%rdi",
         "%r8",  "%r9",  "%r10", "%r11", "%r12", "%r13", "%r14", "%r15" };
   static HChar* ireg32_names[16]
     = { "%eax", "%ecx", "%edx", "%ebx", "%esp", "%ebp", "%esi", "%edi",
         "%r8d", "%r9d", "%r10d","%r11d","%r12d","%r13d","%r14d","%r15d" };
   static HChar* ireg16_names[16]
     = { "%ax",  "%cx",  "%dx",  "%bx",  "%sp",  "%bp",  "%si",  "%di",
         "%r8w", "%r9w", "%r10w","%r11w","%r12w","%r13w","%r14w","%r15w" };
   static HChar* ireg8_names[16]
     = { "%al",  "%cl",  "%dl",  "%bl",  "%spl", "%bpl", "%sil", "%dil",
         "%r8b", "%r9b", "%r10b","%r11b","%r12b","%r13b","%r14b","%r15b" };
   static HChar* ireg8_irregular[8] 
     = { "%al", "%cl", "%dl", "%bl", "%ah", "%ch", "%dh", "%bh" };

   vassert(reg < 16);
   if (sz == 1) {
      if (irregular)
         vassert(reg < 8);
   } else {
      vassert(irregular == False);
   }

   switch (sz) {
      case 8: return ireg64_names[reg];
      case 4: return ireg32_names[reg];
      case 2: return ireg16_names[reg];
      case 1: if (irregular) {
                 return ireg8_irregular[reg];
              } else {
                 return ireg8_names[reg];
              }
      default: vpanic("nameIReg(amd64)");
   }
}

/* Using the same argument conventions as nameIReg, produce the
   guest state offset of an integer register. */

static 
Int offsetIReg ( Int sz, UInt reg, Bool irregular )
{
   vassert(reg < 16);
   if (sz == 1) {
      if (irregular)
         vassert(reg < 8);
   } else {
      vassert(irregular == False);
   }

   /* Deal with irregular case -- sz==1 and no REX present */
   if (sz == 1 && irregular) {
      switch (reg) {
         case R_RSP: return 1+ OFFB_RAX;
         case R_RBP: return 1+ OFFB_RCX;
         case R_RSI: return 1+ OFFB_RDX;
         case R_RDI: return 1+ OFFB_RBX;
         default:    break; /* use the normal case */
      }
   }

   /* Normal case */
   return integerGuestReg64Offset(reg);
}


/* Read the %CL register :: Ity_I8, for shift/rotate operations. */

static IRExpr* getIRegCL ( void )
{
   vassert(!host_is_bigendian);
   return IRExpr_Get( OFFB_RCX, Ity_I8 );
}


/* Write to the %AH register. */

static void putIRegAH ( IRExpr* e )
{
   vassert(!host_is_bigendian);
   vassert(typeOfIRExpr(irbb->tyenv, e) == Ity_I8);
   stmt( IRStmt_Put( OFFB_RAX+1, e ) );
}


/* Read/write various widths of %RAX, as it has various
   special-purpose uses. */

static HChar* nameIRegRAX ( Int sz )
{
   switch (sz) {
      case 1: return "%al";
      case 2: return "%ax";
      case 4: return "%eax";
      case 8: return "%rax";
      default: vpanic("nameIRegRAX(amd64)");
   }
}

static IRExpr* getIRegRAX ( Int sz )
{
   vassert(!host_is_bigendian);
   switch (sz) {
      case 1: return IRExpr_Get( OFFB_RAX, Ity_I8 );
      case 2: return IRExpr_Get( OFFB_RAX, Ity_I16 );
      case 4: return IRExpr_Get( OFFB_RAX, Ity_I32 );
      case 8: return IRExpr_Get( OFFB_RAX, Ity_I64 );
      default: vpanic("getIRegRAX(amd64)");
   }
}

static void putIRegRAX ( Int sz, IRExpr* e )
{
   IRType ty = typeOfIRExpr(irbb->tyenv, e);
   vassert(!host_is_bigendian);
   switch (sz) {
      case 8: vassert(ty == Ity_I64);
              stmt( IRStmt_Put( OFFB_RAX, e ));
              break;
      case 4: vassert(ty == Ity_I32);
              stmt( IRStmt_Put( OFFB_RAX, unop(Iop_32Uto64,e) ));
              break;
      case 2: vassert(ty == Ity_I16);
              stmt( IRStmt_Put( OFFB_RAX, e ));
              break;
      case 1: vassert(ty == Ity_I8);
              stmt( IRStmt_Put( OFFB_RAX, e ));
              break;
      default: vpanic("putIRegRAX(amd64)");
   }
}


/* Read/write various widths of %RDX, as it has various
   special-purpose uses. */

static IRExpr* getIRegRDX ( Int sz )
{
   vassert(!host_is_bigendian);
   switch (sz) {
      case 1: return IRExpr_Get( OFFB_RDX, Ity_I8 );
      case 2: return IRExpr_Get( OFFB_RDX, Ity_I16 );
      case 4: return IRExpr_Get( OFFB_RDX, Ity_I32 );
      case 8: return IRExpr_Get( OFFB_RDX, Ity_I64 );
      default: vpanic("getIRegRDX(amd64)");
   }
}

static void putIRegRDX ( Int sz, IRExpr* e )
{
   vassert(!host_is_bigendian);
   vassert(typeOfIRExpr(irbb->tyenv, e) == szToITy(sz));
   switch (sz) {
      case 8: stmt( IRStmt_Put( OFFB_RDX, e ));
              break;
      case 4: stmt( IRStmt_Put( OFFB_RDX, unop(Iop_32Uto64,e) ));
              break;
      case 2: stmt( IRStmt_Put( OFFB_RDX, e ));
              break;
      case 1: stmt( IRStmt_Put( OFFB_RDX, e ));
              break;
      default: vpanic("putIRegRDX(amd64)");
   }
}


/* Simplistic functions to deal with the integer registers as a
   straightforward bank of 16 64-bit regs. */

static IRExpr* getIReg64 ( UInt regno )
{
   return IRExpr_Get( integerGuestReg64Offset(regno),
                      Ity_I64 );
}

static void putIReg64 ( UInt regno, IRExpr* e )
{
   vassert(typeOfIRExpr(irbb->tyenv,e) == Ity_I64);
   stmt( IRStmt_Put( integerGuestReg64Offset(regno), e ) );
}

static HChar* nameIReg64 ( UInt regno )
{
   return nameIReg( 8, regno, False );
}


/* Simplistic functions to deal with the lower halves of integer
   registers as a straightforward bank of 16 32-bit regs. */

static IRExpr* getIReg32 ( UInt regno )
{
   vassert(!host_is_bigendian);
   return IRExpr_Get( integerGuestReg64Offset(regno),
                      Ity_I32 );
}

static void putIReg32 ( UInt regno, IRExpr* e )
{
   vassert(typeOfIRExpr(irbb->tyenv,e) == Ity_I32);
   stmt( IRStmt_Put( integerGuestReg64Offset(regno), 
                     unop(Iop_32Uto64,e) ) );
}

static HChar* nameIReg32 ( UInt regno )
{
   return nameIReg( 4, regno, False );
}


/* Simplistic functions to deal with the lower quarters of integer
   registers as a straightforward bank of 16 16-bit regs. */

static IRExpr* getIReg16 ( UInt regno )
{
   vassert(!host_is_bigendian);
   return IRExpr_Get( integerGuestReg64Offset(regno),
                      Ity_I16 );
}

static HChar* nameIReg16 ( UInt regno )
{
   return nameIReg( 2, regno, False );
}


/* Sometimes what we know is a 3-bit register number, a REX byte, and
   which field of the REX byte is to be used to extend to a 4-bit
   number.  These functions cater for that situation.  
*/
static IRExpr* getIReg64rexX ( Prefix pfx, UInt lo3bits )
{
   vassert(lo3bits < 8);
   vassert(IS_VALID_PFX(pfx));
   return getIReg64( lo3bits | (getRexX(pfx) << 3) );
}

static HChar* nameIReg64rexX ( Prefix pfx, UInt lo3bits )
{
   vassert(lo3bits < 8);
   vassert(IS_VALID_PFX(pfx));
   return nameIReg( 8, lo3bits | (getRexX(pfx) << 3), False );
}

static HChar* nameIRegRexB ( Int sz, Prefix pfx, UInt lo3bits )
{
   vassert(lo3bits < 8);
   vassert(IS_VALID_PFX(pfx));
   vassert(sz == 8 || sz == 4 || sz == 2 || sz == 1);
   return nameIReg( sz, lo3bits | (getRexB(pfx) << 3), 
                        toBool(sz==1 && !haveREX(pfx)) );
}

static IRExpr* getIRegRexB ( Int sz, Prefix pfx, UInt lo3bits )
{
   vassert(lo3bits < 8);
   vassert(IS_VALID_PFX(pfx));
   vassert(sz == 8 || sz == 4 || sz == 2 || sz == 1);
   return IRExpr_Get(
             offsetIReg( sz, lo3bits | (getRexB(pfx) << 3), 
                             toBool(sz==1 && !haveREX(pfx)) ),
             szToITy(sz)
          );
}

static void putIRegRexB ( Int sz, Prefix pfx, UInt lo3bits, IRExpr* e )
{
   vassert(lo3bits < 8);
   vassert(IS_VALID_PFX(pfx));
   vassert(sz == 8 || sz == 4 || sz == 2 || sz == 1);
   vassert(typeOfIRExpr(irbb->tyenv, e) == szToITy(sz));
   stmt( IRStmt_Put( 
            offsetIReg( sz, lo3bits | (getRexB(pfx) << 3), 
                            toBool(sz==1 && !haveREX(pfx)) ),
            sz==4 ? unop(Iop_32Uto64,e) : e
   ));
}


/* Functions for getting register numbers from modrm bytes and REX
   when we don't have to consider the complexities of integer subreg
   accesses.
*/
/* Extract the g reg field from a modRM byte, and augment it using the
   REX.R bit from the supplied REX byte.  The R bit usually is
   associated with the g register field.
*/
static UInt gregOfRexRM ( Prefix pfx, UChar mod_reg_rm )
{
   Int reg = (Int)( (mod_reg_rm >> 3) & 7 );
   reg += (pfx & PFX_REXR) ? 8 : 0;
   return reg;
}

/* Extract the e reg field from a modRM byte, and augment it using the
   REX.B bit from the supplied REX byte.  The B bit usually is
   associated with the e register field (when modrm indicates e is a
   register, that is).
*/
static UInt eregOfRexRM ( Prefix pfx, UChar mod_reg_rm )
{
   Int rm;
   vassert(epartIsReg(mod_reg_rm));
   rm = (Int)(mod_reg_rm & 0x7);
   rm += (pfx & PFX_REXB) ? 8 : 0;
   return rm;
}


/* General functions for dealing with integer register access. */

/* Produce the guest state offset for a reference to the 'g' register
   field in a modrm byte, taking into account REX (or its absence),
   and the size of the access.
*/
static UInt offsetIRegG ( Int sz, Prefix pfx, UChar mod_reg_rm )
{
   UInt reg;
   vassert(!host_is_bigendian);
   vassert(IS_VALID_PFX(pfx));
   vassert(sz == 8 || sz == 4 || sz == 2 || sz == 1);
   reg = gregOfRexRM( pfx, mod_reg_rm );
   return offsetIReg( sz, reg, toBool(sz == 1 && !haveREX(pfx)) );
}

static 
IRExpr* getIRegG ( Int sz, Prefix pfx, UChar mod_reg_rm )
{
   return IRExpr_Get( offsetIRegG( sz, pfx, mod_reg_rm ),
                      szToITy(sz) );
}

static 
void putIRegG ( Int sz, Prefix pfx, UChar mod_reg_rm, IRExpr* e )
{
   vassert(typeOfIRExpr(irbb->tyenv,e) == szToITy(sz));
   if (sz == 4) {
      e = unop(Iop_32Uto64,e);
   }
   stmt( IRStmt_Put( offsetIRegG( sz, pfx, mod_reg_rm ), e ) );
}

static
HChar* nameIRegG ( Int sz, Prefix pfx, UChar mod_reg_rm )
{
   return nameIReg( sz, gregOfRexRM(pfx,mod_reg_rm),
                        toBool(sz==1 && !haveREX(pfx)) );
}


/* Produce the guest state offset for a reference to the 'e' register
   field in a modrm byte, taking into account REX (or its absence),
   and the size of the access.  eregOfRexRM will assert if mod_reg_rm
   denotes a memory access rather than a register access.
*/
static UInt offsetIRegE ( Int sz, Prefix pfx, UChar mod_reg_rm )
{
   UInt reg;
   vassert(!host_is_bigendian);
   vassert(IS_VALID_PFX(pfx));
   vassert(sz == 8 || sz == 4 || sz == 2 || sz == 1);
   reg = eregOfRexRM( pfx, mod_reg_rm );
   return offsetIReg( sz, reg, toBool(sz == 1 && !haveREX(pfx)) );
}

static 
IRExpr* getIRegE ( Int sz, Prefix pfx, UChar mod_reg_rm )
{
   return IRExpr_Get( offsetIRegE( sz, pfx, mod_reg_rm ),
                      szToITy(sz) );
}

static 
void putIRegE ( Int sz, Prefix pfx, UChar mod_reg_rm, IRExpr* e )
{
   vassert(typeOfIRExpr(irbb->tyenv,e) == szToITy(sz));
   if (sz == 4) {
      e = unop(Iop_32Uto64,e);
   }
   stmt( IRStmt_Put( offsetIRegE( sz, pfx, mod_reg_rm ), e ) );
}

static
HChar* nameIRegE ( Int sz, Prefix pfx, UChar mod_reg_rm )
{
   return nameIReg( sz, eregOfRexRM(pfx,mod_reg_rm),
                        toBool(sz==1 && !haveREX(pfx)) );
}


/*------------------------------------------------------------*/
/*--- For dealing with XMM registers                       ---*/
/*------------------------------------------------------------*/

//.. static Int segmentGuestRegOffset ( UInt sreg )
//.. {
//..    switch (sreg) {
//..       case R_ES: return OFFB_ES;
//..       case R_CS: return OFFB_CS;
//..       case R_SS: return OFFB_SS;
//..       case R_DS: return OFFB_DS;
//..       case R_FS: return OFFB_FS;
//..       case R_GS: return OFFB_GS;
//..       default: vpanic("segmentGuestRegOffset(x86)");
//..    }
//.. }

static Int xmmGuestRegOffset ( UInt xmmreg )
{
   switch (xmmreg) {
      case 0:  return OFFB_XMM0;
      case 1:  return OFFB_XMM1;
      case 2:  return OFFB_XMM2;
      case 3:  return OFFB_XMM3;
      case 4:  return OFFB_XMM4;
      case 5:  return OFFB_XMM5;
      case 6:  return OFFB_XMM6;