src/dec/xed-ild.c

/*BEGIN_LEGAL

Copyright (c) 2018 Intel Corporation

  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at

      http://www.apache.org/licenses/LICENSE-2.0

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.

END_LEGAL */
/// @file xed-ild.c
/// instruction length decoder

/*
  FIXME:

  need these opcode/mode/prefix based tables:
    has_modrm (boolean)
    disp_bytes = 1,2,4,8 bytes
    imm_bytes = 1,2,4,8 bytes

    >90% instructions have MODRM.

        Key on the MOD pattern prebinding

    >90% of the displacements come from the MODRM.MOD byte processing.

        Some come from the pattern:
        Nonterminals: BRDISP8, BRDISP32, MEMDISPv, BRDISPz

    >90% of the are 1B and come from using map3.

        xed grammar has UIMM32, UIMM16, UIMM8,UIMM8_1, SIMM8, SIMMz. The
        signed/unsigned should move to an attribute or the xed_inst_t.  The
        UIMM32 is used on AMD XOP instructions.

        uimm16: opcodes 9A, C2, C8, CA, EA

 */

    /* FIXME:we might have invalid map (TNI maps) - in this case
     * we should check for it before looking up in tables for
     * modrm/imm/disp/static decoding
     * Also invalid map value cannot be 0xFF - we allocate 3 bits
     * for MAP operand in key for static lookup.
     */

#include "xed-internal-header.h"
#include "xed-ild.h"
#include "xed-util-private.h"
#include <string.h> // strcmp

#include "xed-ild-modrm.h"
#include "xed-ild-disp-bytes.h"
#include "xed-ild-imm-bytes.h"
#include "xed-operand-accessors.h"


static XED_INLINE int xed3_mode_64b(xed_decoded_inst_t* d) {
    return (xed3_operand_get_mode(d) == XED_GRAMMAR_MODE_64);
}

/*
 * The scanners cannot return arbitrarily. They MUST return by calling the
 * next scanner.
 */


static void init_has_disp_regular_table(void);
static void init_eamode_table(void);
static void init_has_sib_table(void);
static void set_has_modrm(xed_decoded_inst_t* d);


static void set_hint(xed_uint8_t b,  xed_decoded_inst_t* d){
    switch(b){
    case 0x2e:
        xed3_operand_set_hint(d, 1);
        return;
    case 0x3e:
        xed3_operand_set_hint(d, 2);
        return;
    default:
        xed_assert(0);
    }
}

// conservative filter table for fast prefix checking
// 2014-07-30:
// Timing perftest: 2-6% gain
// Without the filter:
//   Average: 384.08s  Minimum: 352.74s
// With the filter:
//   Average: 362.97s  Minimum: 346.26s
// Could use 2x the space and the 64b mode thing to pick the right table.
// That would speed up 32b prefix decodes.

#define XED_PREFIX_TABLE_SIZE 8
static xed_uint32_t prefix_table[XED_PREFIX_TABLE_SIZE];  // 32B=256b 32*8=2^5*2^3

static void set_prefix_table_bit(xed_uint8_t a)
{
    xed_uint32_t x = a >> 5;
    xed_uint32_t y = a & 0x1F;
    prefix_table[x] |= (1<<y);
}

static XED_INLINE xed_uint_t get_prefix_table_bit(xed_uint8_t a)
{
    // return 1 if the bit is set in the table
    xed_uint32_t x = a >> 5;
    xed_uint32_t y = a & 0x1F;
    return (prefix_table[x] >> y ) & 1;
}

static void init_prefix_table(void);
static void init_prefix_table(void)
{
    int i;
    static xed_uint8_t legacy_prefixes[] = {
        0xF0, // lock
        0x66, // osz
        0x67, // asz

        0xF2, 0xF3, // rep/repne

        0x2E, 0x3E, // 6 segment prefixes
        0x26, 0x36,
        0x64, 0x65,

        0 // sentinel
    };

    for (i=0;i<XED_PREFIX_TABLE_SIZE;i++)
        prefix_table[i]=0;

    for (i=0;legacy_prefixes[i];i++)
        set_prefix_table_bit(legacy_prefixes[i]);

    // add the rex prefixes even for 32b mode
    for(i=0x40;i<0x50;i++)
        set_prefix_table_bit(XED_CAST(xed_uint8_t,i));
}

static void XED_NOINLINE too_short(xed_decoded_inst_t* d)
{
    xed3_operand_set_out_of_bytes(d, 1);
    if ( xed3_operand_get_max_bytes(d) >= XED_MAX_INSTRUCTION_BYTES)
        xed3_operand_set_error(d,XED_ERROR_INSTR_TOO_LONG);
    else
        xed3_operand_set_error(d,XED_ERROR_BUFFER_TOO_SHORT);
}

static void XED_NOINLINE bad_map(xed_decoded_inst_t* d)
{
    xed3_operand_set_map(d,XED_ILD_MAP_INVALID);
    xed3_operand_set_error(d,XED_ERROR_BAD_MAP);
}

#if defined(XED_SUPPORTS_AVX512)
static void XED_NOINLINE bad_v4(xed_decoded_inst_t* d)
{
    xed3_operand_set_error(d,XED_ERROR_BAD_EVEX_V_PRIME);
}
static void XED_NOINLINE bad_z_aaa(xed_decoded_inst_t* d)
{
    xed3_operand_set_error(d,XED_ERROR_BAD_EVEX_Z_NO_MASKING);
}
#endif

static void prefix_scanner(xed_decoded_inst_t* d)
{
    xed_uint8_t max_bytes = xed3_operand_get_max_bytes(d);
    unsigned char length = xed_decoded_inst_get_length(d);
    xed_uint8_t nprefixes = 0;
    xed_uint8_t nseg_prefixes = 0;
    xed_uint8_t nrexes = 0;
    unsigned char rex = 0;

    while(length < max_bytes)
    {
        xed_uint8_t b = xed_decoded_inst_get_byte(d, length);

        // fast check to see if something might be a prefix
        // includes REX prefixes in 32b mode
        if (get_prefix_table_bit(b)==0)
            goto out;

        switch(b) {
          case 0x66:
            xed3_operand_set_osz(d, 1);
            xed3_operand_set_prefix66(d, 1);
            /*ignore possible REX prefix encoutered earlier */
            rex = 0;
            break;

          case 0x67:
            xed3_operand_set_asz(d, 1);
            rex = 0;
            break;

          /* segment prefixes */
          case 0x2E:
          case 0x3E:
            set_hint(b,d);
            //INTENTIONAL FALLTHROUGH
          case 0x26:
          case 0x36:
            if (xed3_mode_64b(d)==0)
                xed3_operand_set_ild_seg(d, b);
            nseg_prefixes++;
            /*ignore possible REX prefix encountered earlier */
            rex = 0;

            break;
          case 0x64:
          case 0x65:
            //for 64b mode we are ignoring non valid segment prefixes
            //only FS=0x64 and GS=0x64 are valid for 64b mode
            xed3_operand_set_ild_seg(d, b);

            nseg_prefixes++;
            /*ignore possible REX prefix encountered earlier */
            rex = 0;
            break;

          case 0xF0:
            xed3_operand_set_lock(d, 1);
            rex = 0;
            break;

          case 0xF3:
            xed3_operand_set_ild_f3(d, 1);
            xed3_operand_set_last_f2f3(d, 3);
            if(xed3_operand_get_first_f2f3(d) == 0)
                xed3_operand_set_first_f2f3(d, 3);

            rex = 0;
            break;

          case 0xF2:
            xed3_operand_set_ild_f2(d, 1);
            xed3_operand_set_last_f2f3(d, 2);
            if(xed3_operand_get_first_f2f3(d) == 0)
                xed3_operand_set_first_f2f3(d, 2);

            rex = 0;
            break;

          default:
             /*Take care of REX prefix */
            if (xed3_mode_64b(d)  &&
                (b & 0xf0) == 0x40) {
                    nrexes++;
                    rex = b;
            }
            else
                goto out;
        }
        length++;
        nprefixes++;
    }
out:
    //set counts
    xed_decoded_inst_set_length(d, length);
    xed3_operand_set_nprefixes(d, nprefixes);
    xed3_operand_set_nseg_prefixes(d, nseg_prefixes);
    xed3_operand_set_nrexes(d, nrexes);

    //set REX, REXW, etc.
    if (rex) {
        xed3_operand_set_rexw(d, (rex>>3) & 1);
        xed3_operand_set_rexr(d, (rex>>2) & 1);
        xed3_operand_set_rexx(d, (rex>>1) & 1);
        xed3_operand_set_rexb(d,  (rex) & 1);
        xed3_operand_set_rex(d, 1);
    }

    //set REP and REFINING
    if (xed3_operand_get_mode_first_prefix(d))
        xed3_operand_set_rep(d, xed3_operand_get_first_f2f3(d));
    else
        xed3_operand_set_rep(d, xed3_operand_get_last_f2f3(d));

    //set SEG_OVD
    /*FIXME: lookup table for seg_ovd ? */
    /*FIXME: make the grammar use the raw byte value instead of the 1..6
     * recoding */
    switch(xed3_operand_get_ild_seg(d)) {
    case 0x2e:
        xed3_operand_set_seg_ovd(d, 1);
        break;
    case 0x3e:
        xed3_operand_set_seg_ovd(d, 2);
        break;
    case 0x26:
        xed3_operand_set_seg_ovd(d, 3);
        break;
    case 0x64:
        xed3_operand_set_seg_ovd(d, 4);
        break;
    case 0x65:
        xed3_operand_set_seg_ovd(d, 5);
        break;
    case 0x36:
        xed3_operand_set_seg_ovd(d, 6);
        break;
    default:
        break;
    }

    //check max bytes
    if (length >= max_bytes) {
        /* all available length was taken by prefixes, but we for sure need
         * at least one additional byte for an opcode, hence we are out of
         * bytes.         */
        too_short(d);
        return;
    }
}

#if defined(XED_AVX) || defined(XED_SUPPORTS_KNC)
//VEX_PREFIX use 2 as F2 and 3 as F3 so table is required.
static unsigned int vex_prefix_recoding[/*pp*/] = { 0,1,3,2 };
#endif

#if defined(XED_AVX)

typedef union { // C4 payload 1
    struct {
        xed_uint32_t map:5;
        xed_uint32_t b_inv:1;
        xed_uint32_t x_inv:1;
        xed_uint32_t r_inv:1;
        xed_uint32_t pad:24;
    } s;
    xed_uint32_t u32;
} xed_avx_c4_payload1_t;

typedef union { // C4 payload 2
    struct {
        xed_uint32_t pp:2;
        xed_uint32_t l:1;
        xed_uint32_t vvv210:3;
        xed_uint32_t v3:1;
        xed_uint32_t w:1;
        xed_uint32_t pad:24;
    } s;
    xed_uint32_t u32;
} xed_avx_c4_payload2_t;

typedef union { // C5 payload 1
    struct {
        xed_uint32_t pp:2;
        xed_uint32_t l:1;
        xed_uint32_t vvv210:3;
        xed_uint32_t v3:1;
        xed_uint32_t r_inv:1;
        xed_uint32_t pad:24;
    } s;
    xed_uint32_t u32;
} xed_avx_c5_payload_t;

static void evex_vex_opcode_scanner(xed_decoded_inst_t* d); //prototype

static void vex_c4_scanner(xed_decoded_inst_t* d)
{
    /* assumption: length < max_bytes
     * This is checked in prefix_scanner.
     * If any other scanner is added before vex_scanner, this condition
     * should be preserved.
     * FIXME: check length < max_bytes here anyway? This will be less
     * error-prone, but that's an additional non-necessary branch.
     */
    xed_uint8_t max_bytes = xed3_operand_get_max_bytes(d);
    unsigned char length  = xed_decoded_inst_get_length(d);
    if (xed3_mode_64b(d))   {
        length++; /* eat the c4/c5 */
    }
    else if (length+1 < max_bytes)   {
        xed_uint8_t n = xed_decoded_inst_get_byte(d, length+1);
        /* in 16/32b modes, the MODRM.MOD field MUST be 0b11 */
        if ((n&0xC0) == 0xC0)    {
            length++; /* eat the c4/c5 */
        }
        else   {
            /* A little optimization:
             * this is not a vex prefix, we can proceed to
             * next scanner */
            return;
        }
    }
    else  {   /* don't have enough bytes to check if it's vex prefix,
           * we are out of bytes */
        too_short(d);
        return ;
    }

    /* pointing at first payload byte. we want to make sure, that we have
     * additional 2 bytes available for reading - for 2nd vex c4 payload
     * byte and opcode */
    if (length + 2 < max_bytes) {
      xed_avx_c4_payload1_t c4byte1;
      xed_avx_c4_payload2_t c4byte2;

      c4byte1.u32 = xed_decoded_inst_get_byte(d, length);
      c4byte2.u32 = xed_decoded_inst_get_byte(d, length + 1);

      // these 2 are guaranteed to be 1 in 16/32b mode by above check
      xed3_operand_set_rexr(d, ~c4byte1.s.r_inv&1);
      xed3_operand_set_rexx(d, ~c4byte1.s.x_inv&1);

      xed3_operand_set_rexb(d, (xed3_mode_64b(d) & ~c4byte1.s.b_inv)&1);

      xed3_operand_set_rexw(d, c4byte2.s.w);

      xed3_operand_set_vexdest3(d,   c4byte2.s.v3);
      xed3_operand_set_vexdest210(d, c4byte2.s.vvv210);

      xed3_operand_set_vl(d,   c4byte2.s.l);

      xed3_operand_set_vex_prefix(d, vex_prefix_recoding[c4byte2.s.pp]);

      xed3_operand_set_map(d,c4byte1.s.map);

      // FIXME: 2017-03-03 this masking of the VEX map with 0x3 an attempt
      // at matching an undocumented implementation convention that can and
      // most likely will change as architectural map usage evolves.
      if ((c4byte1.s.map & 0x3) == XED_ILD_MAP3)
          xed3_operand_set_imm_width(d, bytes2bits(1));

      // this is a success indicator for downstreaam decoding
      xed3_operand_set_vexvalid(d, 1); // AVX1/2

      length += 2; /* eat the c4 vex 2B payload */
      xed_decoded_inst_set_length(d, length);

      evex_vex_opcode_scanner(d);
      return;
    }
    else {
      /* We don't have 3 bytes available for reading, but we for sure
       * need to read them - for 2 vex payload bytes and opcode byte,
       * hence we are out of bytes.
       */
        xed_decoded_inst_set_length(d, length);
        too_short(d);
      return;
    }
}

static void vex_c5_scanner(xed_decoded_inst_t* d)
{
    /* assumption: length < max_bytes
     * This is checked in prefix_scanner.
     * If any other scanner is added before vex_scanner, this condition
     * should be preserved.
     * FIXME: check length < max_bytes here anyway? This will be less
     * error-prone, but that's an additional non-necessary branch.
     */
    xed_uint8_t max_bytes = xed3_operand_get_max_bytes(d);
    unsigned char length  = xed_decoded_inst_get_length(d);
    if (xed3_mode_64b(d))
    {
        length++; /* eat the c4/c5 */
    }
    else if (length + 1 < max_bytes)
    {
        xed_uint8_t n = xed_decoded_inst_get_byte(d, length+1);
        /* in 16/32b modes, the MODRM.MOD field MUST be 0b11 */
        if ((n&0xC0) == 0xC0)
        {
            length++; /* eat the c4/c5 */
        }
        else
        {
            /* A little optimization:
             * this is not a vex prefix, we can proceed to
             * next scanner */
            return;
        }
    }
    else
    {   /* don't have enough bytes to check if it's vex prefix,
         * we are out of bytes */
        too_short(d);
        return ;
    }


    /* pointing at vex c5 payload byte. we want to make sure, that we have
     * additional 2 bytes available for reading - for vex payload byte and
     * opcode */
    if (length + 1 < max_bytes) {
        xed_avx_c5_payload_t c5byte1;
        c5byte1.u32 = xed_decoded_inst_get_byte(d, length);

        xed3_operand_set_rexr(d, ~c5byte1.s.r_inv&1);
        xed3_operand_set_vexdest3(d,   c5byte1.s.v3);
        xed3_operand_set_vexdest210(d, c5byte1.s.vvv210);

        xed3_operand_set_vl(d,   c5byte1.s.l);
        xed3_operand_set_vex_prefix(d, vex_prefix_recoding[c5byte1.s.pp]);

        /* MAP is a special case - although it is a derived operand in
        * newvex_prexix(), we need to set it here, because we use map
        * later in ILD - for modrm, imm and disp
        */
        xed3_operand_set_map(d, XED_ILD_MAP1);

        // this is a success indicator for downstreaam decoding
        xed3_operand_set_vexvalid(d, 1); // AVX1/2

        length++;  /* eat the vex opcode payload */
        xed_decoded_inst_set_length(d, length);

        evex_vex_opcode_scanner(d);  //eats opcode byte
        return;
    }
    else {
        /* We don't have 2 bytes available for reading, but we need to read
         * them - for vex payload byte and opcode bytes, hence we are out
         * of bytes.
         */
        xed_decoded_inst_set_length(d, length);
        too_short(d);
        return ;
    }
}


#if defined(XED_AMD_ENABLED)

static XED_INLINE xed_uint_t get_modrm_reg_field(xed_uint8_t b) {
  return (b & 0x38) >> 3;
}

static void xop_scanner(xed_decoded_inst_t* d)
{
    /* assumption: length < max_bytes
     * This is checked in prefix_scanner.
     * If any other scanner is added before vex_scanner, this condition
     * should be preserved.
     * FIXME: check length < max_bytes here anyway? This will be less
     * error-prone, but that's an additional non-necessary branch.
     */

    /* we don't need to check (d->length < d->max_bytes) because
     * it was already checked in previous scanner (prefix_scanner).
     */
    xed_uint8_t max_bytes = xed3_operand_get_max_bytes(d);
    unsigned char length = xed_decoded_inst_get_length(d);

    if (length + 1 < max_bytes)   {
        xed_uint8_t n = xed_decoded_inst_get_byte(d, length+1);
        /* in all modes, the MODRM.REG field MUST NOT be 0b000.
           mm-rrr-nnn -> mmrr_rnnn
         */

        if ( get_modrm_reg_field(n) != 0 ) {
            length++; /* eat the 0x8f */
        }
        else   {
            /* A little optimization: this is not an xop prefix, we can
             * proceed to next scanner */
            return;
        }
    }
    else  {
        /* don't have enough bytes to check if it's an xop prefix, we
         * are out of bytes */
        too_short(d);
        return ;
    }

    /* pointing at the first xop payload byte. we want to make sure, that
     * we have additional 2 bytes available for reading - for 2nd xop payload
     * byte and opcode */
    if (length + 2 < max_bytes)
    {
      xed_avx_c4_payload1_t xop_byte1;
      xed_avx_c4_payload2_t xop_byte2;
      xed_uint8_t map;
      xop_byte1.u32 = xed_decoded_inst_get_byte(d, length);
      xop_byte2.u32 = xed_decoded_inst_get_byte(d, length + 1);

      map = xop_byte1.s.map;
      if (map == 0x9) {
          xed3_operand_set_map(d,XED_ILD_MAP_XOP9);
          xed3_operand_set_imm_width(d, 0); //bits
      }
      else if (map == 0x8){
          xed3_operand_set_map(d,XED_ILD_MAP_XOP8);
          xed3_operand_set_imm_width(d, bytes2bits(1));
      }
      else if (map == 0xA){
          xed3_operand_set_map(d,XED_ILD_MAP_XOPA);
          xed3_operand_set_imm_width(d, bytes2bits(4));
      }
      else
          bad_map(d);


      xed3_operand_set_rexr(d, ~xop_byte1.s.r_inv&1);
      xed3_operand_set_rexx(d, ~xop_byte1.s.x_inv&1);
      xed3_operand_set_rexb(d, (xed3_mode_64b(d) & ~xop_byte1.s.b_inv)&1);

      xed3_operand_set_rexw(d, xop_byte2.s.w);

      xed3_operand_set_vexdest3(d, xop_byte2.s.v3);
      xed3_operand_set_vexdest210(d, xop_byte2.s.vvv210);

      xed3_operand_set_vl(d, xop_byte2.s.l);
      xed3_operand_set_vex_prefix(d, vex_prefix_recoding[xop_byte2.s.pp]);

      xed3_operand_set_vexvalid(d, 3);

      length += 2; /* eat the 8f xop 2B payload */
      /* FIXME: too hardcoded? maybe define graph data structure?*/
      /* using the VEX opcode scanner for xop opcodes too. */
      xed_decoded_inst_set_length(d, length);
      evex_vex_opcode_scanner(d);
      return;
    }
    else {
      /* We don't have 3 bytes available for reading, but we for sure
       * need to read them - for 2 vex payload bytes and opcode byte,
       * hence we are out of bytes.
       */
        xed_decoded_inst_set_length(d, length);
        too_short(d);
      return;
    }
}
#endif
#endif

#if defined(XED_AVX)

#  if defined(XED_AMD_ENABLED)
static XED_INLINE xed_uint_t chip_is_intel_specific(xed_decoded_inst_t* d)
{
    xed_chip_enum_t chip = xed_decoded_inst_get_input_chip(d);
    if (chip == XED_CHIP_INVALID ||
        chip == XED_CHIP_ALL     ||
        chip == XED_CHIP_AMD)
        return 0;
    return 1;
}
#  endif


static void vex_scanner(xed_decoded_inst_t* d)
{
    /* this handles the AVX C4/C5 VEX prefixes and also the AMD XOP 0x8F
     * prefix */
    unsigned char length = xed_decoded_inst_get_length(d);
    xed_uint8_t b = xed_decoded_inst_get_byte(d, length);
    if (b == 0xC5) {
        if (!xed3_operand_get_out_of_bytes(d))
            vex_c5_scanner(d);
        return;
    }
    else if (b == 0xC4) {
        if (!xed3_operand_get_out_of_bytes(d))
            vex_c4_scanner(d);
        return;
    }
#if defined(XED_AMD_ENABLED)
    else if (b == 0x8f && chip_is_intel_specific(d)==0 )  {
        if (!xed3_operand_get_out_of_bytes(d))
            xop_scanner(d);
        return;
    }
#endif
}
#endif

static void get_next_as_opcode(xed_decoded_inst_t* d) {
    unsigned char length = xed_decoded_inst_get_length(d);
    if (length < xed3_operand_get_max_bytes(d)) {
        xed_uint8_t b = xed_decoded_inst_get_byte(d, length);
        xed3_operand_set_nominal_opcode(d, b);
        xed_decoded_inst_inc_length(d);
        //st SRM (partial opcode instructions need it)
        xed3_operand_set_srm(d, xed_modrm_rm(b));
    }
    else {
        too_short(d);
    }
}


// has_disp_regular[eamode][modrm.mod][modrm.rm]
static xed_uint8_t has_disp_regular[3][4][8];

static void init_has_disp_regular_table(void) {
    xed_uint8_t eamode;
    xed_uint8_t rm;
    xed_uint8_t mod;

    for (eamode = 0; eamode <3; eamode++)
        for (mod=0; mod < 4; mod++)
            for (rm=0; rm<8; rm++)
                has_disp_regular[eamode][mod][rm] = 0;

    //fill the eamode16
    has_disp_regular[0][0][6] = 2;
    for (rm = 0; rm < 8; rm++) {
        for (mod = 1; mod <= 2; mod++)
            has_disp_regular[0][mod][rm] = mod;
    }

    //fill eamode32/64
    for(eamode = 1; eamode <= 2; eamode++) {
        for (rm = 0; rm < 8; rm++) {
            has_disp_regular[eamode][1][rm] = 1;
            has_disp_regular[eamode][2][rm] = 4;
        };
        has_disp_regular[eamode][0][5] = 4;

    }
}

// eamode_table[asz][mmode]
static xed_uint8_t eamode_table[2][XED_GRAMMAR_MODE_64+1];

static void init_eamode_table(void) {
    xed_uint8_t mode;
    xed_uint8_t asz;

    for (asz=0; asz<2; asz++)
        for (mode=0; mode<XED_GRAMMAR_MODE_64+1; mode++)
            eamode_table[asz][mode] = 0;


    for (mode = XED_GRAMMAR_MODE_16; mode <= XED_GRAMMAR_MODE_64; mode ++) {
        eamode_table[0][mode] = mode;
    }

    eamode_table[1][XED_GRAMMAR_MODE_16] = XED_GRAMMAR_MODE_32;
    eamode_table[1][XED_GRAMMAR_MODE_32] = XED_GRAMMAR_MODE_16;
    eamode_table[1][XED_GRAMMAR_MODE_64] = XED_GRAMMAR_MODE_32;
}


// has_sib_table[eamode][modrm.mod][modrm.rm]
static xed_uint8_t has_sib_table[3][4][8];

static void init_has_sib_table(void) {
    xed_uint8_t eamode;
    xed_uint8_t mod;
    xed_uint8_t rm;

    for (eamode = 0; eamode <3; eamode++)
        for (mod=0; mod < 4; mod++)
            for (rm=0; rm<8; rm++)
                has_sib_table[eamode][mod][rm] = 0;

    //for eamode32/64 there is sib byte for mod!=3 and rm==4
    for(eamode = 1; eamode <= 2; eamode++) {
        for (mod = 0; mod <= 2; mod++) {
            has_sib_table[eamode][mod][4] = 1;
        }
    }
}


#if defined(XED_SUPPORTS_AVX512)
static void bad_ll(xed_decoded_inst_t* d) {
    xed3_operand_set_error(d,XED_ERROR_BAD_EVEX_LL);
}


static void bad_ll_check(xed_decoded_inst_t* d)
{
    if (xed3_operand_get_llrc(d) == 3)  {
        // we have a potentially bad EVEX.LL field.
        if (xed3_operand_get_mod(d) != 3) // memop
            bad_ll(d);
        else if (xed3_operand_get_bcrc(d)==0) // reg-reg but not rounding
            bad_ll(d);
    }
}
#endif

static void modrm_scanner(xed_decoded_inst_t* d)
{
    xed_uint8_t b;
    xed_uint8_t has_modrm;
    set_has_modrm(d);

    has_modrm = xed3_operand_get_has_modrm(d);

    if (has_modrm) {
        unsigned char length = xed_decoded_inst_get_length(d);
        if (length < xed3_operand_get_max_bytes(d)) {
            xed_uint8_t eamode;
            xed_uint8_t mod;
            xed_uint8_t rm;

            b = xed_decoded_inst_get_byte(d, length);
            xed3_operand_set_modrm_byte(d, b);
            xed3_operand_set_pos_modrm(d, length);
            xed_decoded_inst_inc_length(d); /* eat modrm */

            mod = xed_modrm_mod(b);
            rm = xed_modrm_rm(b);
            xed3_operand_set_mod(d, mod);
            xed3_operand_set_rm(d, rm);
            xed3_operand_set_reg(d, xed_modrm_reg(b));

#if defined(XED_SUPPORTS_AVX512)
            bad_ll_check(d);
#endif
            /*This checks that we are not in MOV_DR or MOV_CR instructions
            that ignore MODRM.MOD bits and don't have DISP and SIB */
            if (has_modrm != XED_ILD_HASMODRM_IGNORE_MOD) {
                xed_uint8_t asz = xed3_operand_get_asz(d);
                xed_uint8_t mode = xed3_operand_get_mode(d);
                // KW complains here but it is stupid. Code is fine.
                eamode = eamode_table[asz][mode];

                xed_assert(eamode <= 2);

                /* opcode scanner (and prefix scanner) doesn't set
                disp_bytes, hence we can set it to 0  without worrying about
                overriding a value that was set earlier. */

                xed3_operand_set_disp_width(
                    d,
                    bytes2bits(has_disp_regular[eamode][mod][rm]));

                /*same with sib, we will not override data set earlier here*/
                xed3_operand_set_has_sib(d, has_sib_table[eamode][mod][rm]);


            }
            return;
        }
        else {
            /*need modrm, but length >= max_bytes, and we are out of bytes*/
            too_short(d);
            return;
        }

    }
    /*no modrm, set RM from nominal_opcode*/
    //rm = xed_modrm_rm(xed3_operand_get_nominal_opcode(d));
    //xed3_operand_set_rm(d, rm);

    /* a little optimization: we don't have modrm and hence don't have sib.
     * Hence we don't need to call sib scanner and can go straight to disp*/
    /*FIXME: Better to call next scanner anyway for better modularity?*/
}

static void sib_scanner(xed_decoded_inst_t* d)
{

  if (xed3_operand_get_has_sib(d)) {
      unsigned char length = xed_decoded_inst_get_length(d);
      if (length < xed3_operand_get_max_bytes(d)) {
          xed_uint8_t b;
          b = xed_decoded_inst_get_byte(d, length);

          xed3_operand_set_pos_sib(d, length);
          xed3_operand_set_sibscale(d, xed_sib_scale(b));
          xed3_operand_set_sibindex(d, xed_sib_index(b));
          xed3_operand_set_sibbase(d, xed_sib_base(b));

          xed_decoded_inst_inc_length(d); /* eat sib */

          if (xed_sib_base(b) == 5) {
              /* other mod values are set by modrm processing */
              if (xed3_operand_get_mod(d) == 0)
                  xed3_operand_set_disp_width(d, bytes2bits(4));
          }
      }
      else { /*has_sib but not enough length -> out of bytes */
          too_short(d);
          return;
      }
  }
}


/*probably this table should be generated. Leaving it here for now.
  Maybe in one of the following commits it will be moved to auto generated
  code.*/
const xed_ild_l1_func_t* disp_bits_2d[XED_ILD_MAP2] = {
    disp_width_map_0x0,
    disp_width_map_0x0F
};

static void disp_scanner(xed_decoded_inst_t* d)
{
    /*                                   0   1  2  3   4  5   6   7   8 */
    static const xed_uint8_t ilog2[] = { 99 , 0, 1, 99, 2, 99, 99, 99, 3 };

    xed_ild_map_enum_t map = (xed_ild_map_enum_t)xed3_operand_get_map(d);
    xed_uint8_t opcode = xed3_operand_get_nominal_opcode(d);
    xed_uint8_t disp_bytes;
    xed_uint8_t length = xed_decoded_inst_get_length(d);
    /*Checked dumped tables of maps 2 ,3 and 3dnow:
      they all have standard displacement resolution, we are not going
      to use their lookup tables*/
  if (map < XED_ILD_MAP2) {
      /*get the L1 function pointer and use it */
        xed_ild_l1_func_t fptr = disp_bits_2d[map][opcode];
        /*most map-opcodes have disp_bytes set in modrm/sib scanners
          for those we  have L1 functions that do nothing*/
        if (fptr == 0){
            xed3_operand_set_error(d,XED_ERROR_GENERAL_ERROR);
            return;
        }
        (*fptr)(d);
  }
  /*All other maps should have been set earlier*/
  disp_bytes = bits2bytes(xed3_operand_get_disp_width(d));
  if (disp_bytes) {
      xed_uint8_t max_bytes = xed3_operand_get_max_bytes(d);
      if ((length + disp_bytes) <= max_bytes) {

          //set disp value
          const xed_uint8_t* itext = d->_byte_array._dec;
          xed_uint8_t* disp_ptr = (xed_uint8_t*)(itext + length);

          // sign extend the displacement to 64b while passing to accessor

          switch(ilog2[disp_bytes]) {
            case 0: { // 1B=8b. ilog2(1) = 0
                xed_int8_t byte = *(xed_int8_t*)disp_ptr;
                xed3_operand_set_disp(d, byte);
                break;
            }
            case 1: { // 2B=16b ilog2(2) = 1
                xed_int16_t word = *(xed_int16_t*)disp_ptr;
                xed3_operand_set_disp(d, word);
                break;
            }
            case 2: { // 4B=32b ilog2(4) = 2
                xed_int32_t dword = *(xed_int32_t*)disp_ptr;
                xed3_operand_set_disp(d, dword);
                break;
            }
            case 3: {// 8B=64b ilog2(8) = 3
                xed_int64_t qword = *(xed_int64_t*)disp_ptr;
                xed3_operand_set_disp(d, qword);
                break;
            }
            default:
              xed_assert(0);
          }

          xed3_operand_set_pos_disp(d, length);
          xed_decoded_inst_set_length(d, length + disp_bytes);
      }
      else {
          too_short(d);
          return;
      }
  }
}


#if defined(XED_EXTENDED)
# include "xed-ild-extension.h"
#endif

/*probably this table should be generated. Leaving it here for now.
  Maybe in one of the following commits it will be moved to auto generated
  code.*/
const xed_uint8_t* has_modrm_2d[XED_ILD_MAP2] = {
    has_modrm_map_0x0,
    has_modrm_map_0x0F
};

static void set_has_modrm(xed_decoded_inst_t* d) {
    /* This assumes that the lookup arrays do not have undefined opcodes.
       It means we must fill has_modrm property for illegal opcodes at
       build time in (ild.py) */
    /*some 3dnow instructions conflict on has_modrm property with other
      instructions. However all 3dnow instructions have modrm, hence we
      just set has_modrm to 1 in case of 3dnow (map==XED_ILD_MAPAMD) */
    xed_ild_map_enum_t map = (xed_ild_map_enum_t)xed3_operand_get_map(d);
    xed_uint8_t opcode = xed3_operand_get_nominal_opcode(d);
    xed3_operand_set_has_modrm(d,1);
    if (map < XED_ILD_MAP2) {
        // need to set more complex codes like XED_ILD_HASMODRM_IGNORE_MOD
        // from the has_modrm_2d[][] tables.
        xed3_operand_set_has_modrm(d,has_modrm_2d[map][opcode]);
    }
}


/*probably this table should be generated. Leaving it here for now.
  Maybe in one of the following commits it will be moved to auto generated
  code.*/
const xed_ild_l1_func_t* imm_bits_2d[XED_ILD_MAP2] = {
    imm_width_map_0x0,
    imm_width_map_0x0F
};

static void set_imm_bytes(xed_decoded_inst_t* d) {
    xed_ild_map_enum_t map = (xed_ild_map_enum_t)xed3_operand_get_map(d);
    xed_uint8_t opcode = xed3_operand_get_nominal_opcode(d);
    xed_uint8_t imm_bits = xed3_operand_get_imm_width(d);
    /* FIXME: not taking care of illegal map-opcodes yet.
    Probably should fill them in ild_storage.py
    Now illegal map-opcodes have 0 as function pointer in lookup tables*/
    if (!imm_bits) {
         if (map < XED_ILD_MAP2) {
             /*get the L1 function pointer and use it */
            xed_ild_l1_func_t fptr = imm_bits_2d[map][opcode];
            if (fptr == 0){
                xed3_operand_set_error(d,XED_ERROR_GENERAL_ERROR);
                return;
            }
            (*fptr)(d);
            return;
         }
         /*All other maps should have been set earlier*/
    }
}

////////////////////////////////////////////////////////////////////////////////

#if !defined(XED_SUPPORTS_AVX512) && !defined(XED_SUPPORTS_KNC)
static void imm_scanner(xed_decoded_inst_t* d)
{
  xed_uint8_t imm_bytes;
  xed_uint8_t imm1_bytes;
  xed_uint8_t max_bytes = xed3_operand_get_max_bytes(d);
  unsigned char length = xed_decoded_inst_get_length(d);
  unsigned int pos_imm = 0;
  const xed_uint8_t* itext = d->_byte_array._dec;
  const xed_uint8_t* imm_ptr = 0;

  set_imm_bytes(d);
#if defined(XED_AMD_ENABLED)
  if (xed3_operand_get_amd3dnow(d)) {
      if (length < max_bytes) {
         /*opcode is in immediate*/
          xed3_operand_set_nominal_opcode(d,
              xed_decoded_inst_get_byte(d, length));
          /*count the pseudo immediate byte, which is opcode*/
          xed_decoded_inst_inc_length(d);
          /*imm_bytes == imm_bytes1 == 0 for amd3dnow */
          return;
      }
      else {
          too_short(d);
          return;
      }
  }
#endif

  imm_bytes = bits2bytes(xed3_operand_get_imm_width(d));
  imm1_bytes = xed3_operand_get_imm1_bytes(d);

  if (imm_bytes)  {
      if (length + imm_bytes <= max_bytes) {
          xed3_operand_set_pos_imm(d, length);
          /* eat imm */
          length += imm_bytes;
          xed_decoded_inst_set_length(d, length);

          if (imm1_bytes)  {
              if (length + imm1_bytes <= max_bytes) {
                  xed3_operand_set_pos_imm1(d, length);
                  imm_ptr = itext + length;
                  length += imm1_bytes; /* eat imm1 */
                  xed_decoded_inst_set_length(d, length);
                  //set uimm1 value
                  xed3_operand_set_uimm1(d, *imm_ptr);
              }
              else {/* Ugly code */
                    too_short(d);
                    return;
              }
            }
      }
      else {
          too_short(d);
          return;
      }
  }

  /* FIXME: setting UIMM chunks. This can be done better,
   * for example special capturing function in ILD, like for imm_bytes*/
  pos_imm = xed3_operand_get_pos_imm(d);
  imm_ptr = itext + pos_imm;
  switch(imm_bytes){
  case 0:
      break;
  case 1: {
      xed_uint8_t uimm0 =  *(xed_uint8_t*)(imm_ptr);
      xed3_operand_set_uimm0(d, uimm0);

      //for SE_IMM8() we need to set here the esrc as well
      xed3_operand_set_esrc(d,uimm0 >> 4);
      break;
          }
  case 2:{
      xed_uint16_t uimm0 =  *(xed_uint16_t*)(imm_ptr);
      xed3_operand_set_uimm0(d, uimm0);
      break;
      }
  case 4:{
      xed_uint32_t uimm0 =  *(xed_uint32_t*)(imm_ptr);
      xed3_operand_set_uimm0(d, uimm0);
      break;
      }
  case 8:{
      xed_uint64_t uimm0 =  *(xed_uint64_t*)(imm_ptr);
      xed3_operand_set_uimm0(d, uimm0);
      break;
      }
  default:
      /*Unexpected immediate width, this should never happen*/
      xed_assert(0);
  }

  /* uimm1 is set earlier */
}
#endif // !defined(XED_SUPPORTS_AVX512) && !defined(XED_SUPPORTS_KNC)
////////////////////////////////////////////////////////////////////////////////

#if defined(XED_AVX)
static void catch_invalid_rex_or_legacy_prefixes(xed_decoded_inst_t* d)
{
    // REX, F2, F3, 66 are not allowed before VEX or EVEX prefixes
    if ( xed3_mode_64b(d) && xed3_operand_get_rex(d) )
        xed3_operand_set_error(d,XED_ERROR_BAD_REX_PREFIX);
    else if ( xed3_operand_get_osz(d) ||
              xed3_operand_get_ild_f3(d) ||
              xed3_operand_get_ild_f2(d) )
        xed3_operand_set_error(d,XED_ERROR_BAD_LEGACY_PREFIX);
}
static void catch_invalid_mode(xed_decoded_inst_t* d)
{
    // we know we have VEX or EVEX instr.
    if(xed3_operand_get_realmode(d)) {
        xed3_operand_set_error(d,XED_ERROR_INVALID_MODE);
    }
}

static void evex_vex_opcode_scanner(xed_decoded_inst_t* d)
{
    /* no need to check max_bytes here, it was checked in previous
    scanner */
    unsigned char length = xed_decoded_inst_get_length(d);
    xed_uint8_t b = xed_decoded_inst_get_byte(d, length);
    xed3_operand_set_nominal_opcode(d, b);
    xed3_operand_set_pos_nominal_opcode(d, length);
    xed_decoded_inst_inc_length(d);
    catch_invalid_rex_or_legacy_prefixes(d);
    catch_invalid_mode(d);
}
#endif

static void opcode_scanner(xed_decoded_inst_t* d)
{
    unsigned char length = xed_decoded_inst_get_length(d);
    xed_uint8_t b = xed_decoded_inst_get_byte(d, length);
    xed_uint8_t opcode = 0;

    /*no need to check max_bytes - it was checked in previous scanners*/

    /* no need to check for VEX here anymore, because if VEX
    prefix was encountered, we would get to evex_vex_opcode_scanner */
    if (b != 0x0F) {
        xed3_operand_set_map(d, XED_ILD_MAP0);
        xed3_operand_set_nominal_opcode(d, b);
        xed3_operand_set_pos_nominal_opcode(d, length);
        xed_decoded_inst_inc_length(d);
        goto out;
    }

    length++; /* eat the 0x0F */
    xed3_operand_set_pos_nominal_opcode(d, length);

    /* 0x0F opcodes MAPS 1,2,3 */
    //FIXME: finish here
    if (length < xed3_operand_get_max_bytes(d)) {
        xed_uint8_t m = xed_decoded_inst_get_byte(d, length);
        if (m == 0x38) {
            length++; /* eat the 0x38 */
            xed3_operand_set_map(d, XED_ILD_MAP2);
            xed_decoded_inst_set_length(d, length);
            get_next_as_opcode( d);
            return;
        }
        else if (m == 0x3A) {
            length++; /* eat the 0x3A */
            xed3_operand_set_map(d, XED_ILD_MAP3);
            xed_decoded_inst_set_length(d, length);
            xed3_operand_set_imm_width(d, bytes2bits(1));
            get_next_as_opcode( d);
            return;
        }
        else if (m == 0x3B) {
            length++; /* eat the 0x3B */
            bad_map(d);
            xed_decoded_inst_set_length(d, length);
            get_next_as_opcode( d);
            return;
            //FIXME: TNI maps have no modrm, imm, disp ??
            /* BTW we use MAP as index to static decoding lookup tables..
             * with INVALID_MAP we will have segv there, need to check
             * for it after ILD phase.
             * Maybe set some common ILD_INVALID member to indicate that
             * there is no need to do static decoding?
             */
        }
        else if (m > 0x38 && m <= 0x3F) {
            length++; /* eat the 0x39...0x3F (minus 3A and 3B) */
            bad_map(d);

            xed_decoded_inst_set_length(d, length);
            get_next_as_opcode( d);
            return; //FIXME: TNI maps have no modrm, imm, disp ??
            /* BTW we use MAP as index static decoding lookup tables..
             * with INVALID_MAP we will have segv there, need to check
             * for it after ILD phase */
        }
#if defined(XED_AMD_ENABLED)
        else if (m == 0x0F) {
            xed3_operand_set_amd3dnow(d, 1);
            /* opcode is in immediate later on */
            length++; /*eat the second 0F */
            xed3_operand_set_nominal_opcode(d, 0x0F);
             /*special map for amd3dnow */
            xed3_operand_set_map(d, XED_ILD_MAPAMD);
            xed_decoded_inst_set_length(d, length);
        }
#endif
        else {
            length++; /* eat the 2nd  opcode byte */
            xed3_operand_set_nominal_opcode(d, m);
            xed3_operand_set_map(d, XED_ILD_MAP1);
            xed_decoded_inst_set_length(d, length);
        }
    }
    else{
        too_short(d);
        return;
    }

out:
    //set SRM (partial opcode instructions need it)
    opcode = xed3_operand_get_nominal_opcode(d);
    xed3_operand_set_srm(d, xed_modrm_rm(opcode));
}

//////////////////////////////////////////////////////////////////////////
// KNC/AVX512 EVEX and EVEX-IMM8 scanners


#if defined(XED_SUPPORTS_AVX512) || defined(XED_SUPPORTS_KNC)

typedef union { // Common KNC & AVX512
    struct {
        xed_uint32_t map:4;
        xed_uint32_t rr_inv:1;
        xed_uint32_t b_inv:1;
        xed_uint32_t x_inv:1;
        xed_uint32_t r_inv:1;
        xed_uint32_t pad:24;
    } s;
    xed_uint32_t u32;
} xed_avx512_payload1_t;

typedef union { // Common KNC & AVX512
    struct {
        xed_uint32_t pp:2;
        xed_uint32_t ubit:1;
        xed_uint32_t vexdest210:3;
        xed_uint32_t vexdest3:1;
        xed_uint32_t rexw:1;
        xed_uint32_t pad:24;
    } s;
    xed_uint32_t u32;
} xed_avx512_payload2_t;

typedef union{  // KNC only
    struct  {
        xed_uint32_t mask:3;
        xed_uint32_t vexdest4p:1;
        xed_uint32_t swiz:3;
        xed_uint32_t nr:1;
        xed_uint32_t pad:24;
    } s;
    xed_uint32_t u32;
} xed_knc_payload3_t;


typedef union{  // AVX512 only
    struct  {
        xed_uint32_t mask:3;
        xed_uint32_t vexdest4p:1;
        xed_uint32_t bcrc:1;
        xed_uint32_t llrc:2;
        xed_uint32_t z:1;
        xed_uint32_t pad:24;
    } s;
    xed_uint32_t u32;
} xed_avx512_payload3_t;


static void evex_scanner(xed_decoded_inst_t* d)
{
     /* assumption: length < max_bytes
     * This is checked in prefix_scanner.
     * If any other scanner is added before evex_scanner, this condition
     * should be preserved.
     * FIXME: check length < max_bytes here anyway? This will be less
     * error-prone, but that's an additional non-necessary branch.
     */
    xed_uint8_t max_bytes = xed3_operand_get_max_bytes(d);
    unsigned char length = xed_decoded_inst_get_length(d);
    xed_uint8_t b = xed_decoded_inst_get_byte(d, length);

    if (b == 0x62)
    {
        /*first check that it is not a BOUND instruction */
        if(!xed3_mode_64b(d)) {
            /*make sure we can read one additional byte */
            if (length + 1 < max_bytes) {
                xed_uint8_t n = xed_decoded_inst_get_byte(d, length+1);
                if ((n&0xC0) != 0xC0) {
                    /*this is a BOUND instruction */
                    /* FIXME: could have set opcode here and call
                     * modrm_scanner but that would be a code
                     * duplication */
                    return;
                }
            }
            else {
                too_short(d);
                return;
            }
        }
        /*Unlike the vex and xop prefix scanners, here length is pointing
        at the evex prefix byte.  We want to ensure that we have enough
        bytes available to read 4 bytes for evex prefix and 1 byte for an
        opcode */
        if (length + 4 < max_bytes) {
            xed_avx512_payload1_t evex1;
            xed_avx512_payload2_t evex2;

            evex1.u32 = xed_decoded_inst_get_byte(d, length+1);
            evex2.u32 = xed_decoded_inst_get_byte(d, length+2);

            // above check guarantees that r and x are 1 in 16/32b mode.
            if (xed3_mode_64b(d)) {
                xed3_operand_set_rexr(d,  ~evex1.s.r_inv&1);
                xed3_operand_set_rexx(d,  ~evex1.s.x_inv&1);
                xed3_operand_set_rexb(d,  ~evex1.s.b_inv&1);
                xed3_operand_set_rexrr(d, ~evex1.s.rr_inv&1);
            }

            xed3_operand_set_map(d, evex1.s.map);

            xed3_operand_set_rexw(d,   evex2.s.rexw);
            xed3_operand_set_vexdest3(d,  evex2.s.vexdest3);
            xed3_operand_set_vexdest210(d, evex2.s.vexdest210);
            xed3_operand_set_ubit(d, evex2.s.ubit);
            if (evex2.s.ubit)
                xed3_operand_set_vexvalid(d, 2); // AVX512 EVEX U=1 req'd
            else
            {
#if defined(XED_SUPPORTS_KNC)
                xed3_operand_set_vexvalid(d, 4); // KNC EVEX U=0 req'd
#else
                xed3_operand_set_error(d,XED_ERROR_BAD_EVEX_UBIT);
#endif
            }

            xed3_operand_set_vex_prefix(d,vex_prefix_recoding[evex2.s.pp]);

            if (evex1.s.map == XED_ILD_MAP3)
                xed3_operand_set_imm_width(d, bytes2bits(1));

            if (evex2.s.ubit)  // AVX512 only (Not KNC)
            {
#if defined(XED_SUPPORTS_AVX512)
                xed_avx512_payload3_t evex3;
                evex3.u32 = xed_decoded_inst_get_byte(d, length+3);

                xed3_operand_set_zeroing(d, evex3.s.z);

                // llrc is still required for rounding fixup much later
                // during decode.
                xed3_operand_set_llrc(d, evex3.s.llrc);

                xed3_operand_set_vl(d, evex3.s.llrc);
                xed3_operand_set_bcrc(d, evex3.s.bcrc);
                xed3_operand_set_vexdest4(d, ~evex3.s.vexdest4p&1);
                if (!xed3_mode_64b(d) && evex3.s.vexdest4p==0)
                    bad_v4(d);

                xed3_operand_set_mask(d, evex3.s.mask);
                if (evex3.s.mask == 0 && evex3.s.z == 1)
                    bad_z_aaa(d);
#endif
            }
#if defined(XED_SUPPORTS_KNC)
            else // KNC
            {
                const xed_uint_t vl_512=2;
                xed_knc_payload3_t evex3;
                evex3.u32 = xed_decoded_inst_get_byte(d, length+3);
                xed3_operand_set_vl(d, vl_512); //Indicates vector length 512b

                xed3_operand_set_nr(d, evex3.s.nr);
                xed3_operand_set_swiz(d, evex3.s.swiz);
                xed3_operand_set_vexdest4(d, ~evex3.s.vexdest4p&1);
                xed3_operand_set_mask(d, evex3.s.mask);
            }
#endif

            length += 4;
            xed_decoded_inst_set_length(d, length);
            /* vex opcode scanner fits for evex instructions too: it just reads
             * one byte as nominal opcode, this is exactly what we want for
             * evex*/
            evex_vex_opcode_scanner(d);
        }
        else {
            /*there is no enough bytes, hence we are out of bytes */
            too_short(d);
        }
    }
}

static void evex_imm_scanner(xed_decoded_inst_t* d)
{
  xed_uint8_t imm_bytes;
  xed_uint8_t imm1_bytes;
  xed_uint8_t max_bytes = xed3_operand_get_max_bytes(d);
  unsigned char length = xed_decoded_inst_get_length(d);
  unsigned int pos_imm = 0;
  const xed_uint8_t* itext = d->_byte_array._dec;
  const xed_uint8_t* imm_ptr = 0;

  set_imm_bytes(d);

#if defined(XED_AMD_ENABLED)
  if (xed3_operand_get_amd3dnow(d)) {
      if (length < max_bytes) {
         /*opcode is in immediate*/
          xed3_operand_set_nominal_opcode(d,
              xed_decoded_inst_get_byte(d, length));
          /*count the pseudo immediate byte, which is opcode*/
          xed_decoded_inst_inc_length(d);
          /*imm_bytes == imm_bytes1 == 0 for amd3dnow */
          return;
      }
      else {
          too_short(d);
          return;
      }
  }
#endif

  imm_bytes = bits2bytes(xed3_operand_get_imm_width(d));
  imm1_bytes = xed3_operand_get_imm1_bytes(d);

  if (imm_bytes)  {
      if (length + imm_bytes <= max_bytes) {
          xed3_operand_set_pos_imm(d, length);
          /* eat imm */
          length += imm_bytes;
          xed_decoded_inst_set_length(d, length);

          if (imm1_bytes)  {
              if (length + imm1_bytes <= max_bytes) {
                  xed3_operand_set_pos_imm1(d, length);
                  imm_ptr = itext + length;
                  length += imm1_bytes; /* eat imm1 */
                  xed_decoded_inst_set_length(d, length);
                  //set uimm1 value
                  xed3_operand_set_uimm1(d, *imm_ptr);
              }
              else {/* Ugly code */
                    too_short(d);
                    return;
              }
            }
      }
      else {
          too_short(d);
          return;
      }
  }

  /* FIXME: setting UIMM chunks. This can be done better,
   * for example special capturing function in ILD, like for imm_bytes*/
  pos_imm = xed3_operand_get_pos_imm(d);
  imm_ptr = itext + pos_imm;
  switch(imm_bytes)
  {
  case 0:
      break;
  case 1:
    {
        xed_uint8_t uimm0 =  *imm_ptr;
        xed_uint8_t esrc = uimm0 >> 4;

        xed3_operand_set_uimm0(d, uimm0);
        xed3_operand_set_esrc(d, esrc);
        break;
    }
  case 2:
      xed3_operand_set_uimm0(d, *(xed_uint16_t*)imm_ptr);
      break;
  case 4:
      xed3_operand_set_uimm0(d, *(xed_uint32_t*)imm_ptr);
      break;
  case 8:
      xed3_operand_set_uimm0(d, *(xed_uint64_t*)imm_ptr);
      break;
  default:
      /*Unexpected immediate width, this should never happen*/
      xed_assert(0);
  }

  /* uimm1 is set earlier */
}

#endif // defined(XED_SUPPORTS_AVX512)

////////////////////////////////////////////////////////////////////////////////

void xed_ild_lookup_init(void) {
    xed_ild_eosz_init();
    xed_ild_easz_init();

    xed_ild_imm_l3_init();
    xed_ild_disp_l3_init();

    init_has_disp_regular_table();
    init_eamode_table();
    init_has_sib_table();

}

void xed_ild_init(void) {
    init_prefix_table();
    xed_ild_lookup_init();
}


void
xed_instruction_length_decode(xed_decoded_inst_t* ild)
{
    prefix_scanner(ild);
#if defined(XED_AVX)
    if (xed3_operand_get_out_of_bytes(ild))
        return;
    vex_scanner(ild);
#endif
#if defined(XED_SUPPORTS_AVX512) || defined(XED_SUPPORTS_KNC)
    // if we got a vex prefix (which also sucks down the opcode),
    // then we do not need to scan for evex prefixes.
    if (!xed3_operand_get_vexvalid(ild)) {
        if (xed3_operand_get_out_of_bytes(ild))
            return;
        evex_scanner(ild);
    }
#endif

    if (xed3_operand_get_out_of_bytes(ild))
        return;
#if defined(XED_AVX)
    // vex/xop prefixes also eat the vex/xop opcode
    if (!xed3_operand_get_vexvalid(ild))
        opcode_scanner(ild);
#else
    opcode_scanner(ild);
#endif
    modrm_scanner(ild);
    sib_scanner(ild);
    disp_scanner(ild);
#if defined(XED_SUPPORTS_AVX512) || defined(XED_SUPPORTS_KNC)
    evex_imm_scanner(ild);
#else
    imm_scanner(ild);
#endif
}

#include "xed-chip-modes.h"

/// This is the second main entry point for the decoder
/// used for new xed3 decoding.
XED_DLL_EXPORT xed_error_enum_t
xed_ild_decode(xed_decoded_inst_t* xedd,
           const xed_uint8_t* itext,
           const unsigned int bytes)
{
    xed_uint_t tbytes;
    xed_chip_enum_t chip = xed_decoded_inst_get_input_chip(xedd);

    set_chip_modes(xedd,chip,0); //FIXME: add support for cpuid features

    xedd->_byte_array._dec = itext;

    tbytes =  bytes;
    if (bytes > XED_MAX_INSTRUCTION_BYTES)
        tbytes = XED_MAX_INSTRUCTION_BYTES;
    xed3_operand_set_max_bytes(xedd, tbytes);
    xed_instruction_length_decode(xedd);

    if (xed3_operand_get_out_of_bytes(xedd))
        return XED_ERROR_BUFFER_TOO_SHORT;
    if (xed3_operand_get_map(xedd) == XED_ILD_MAP_INVALID)
        return XED_ERROR_GENERAL_ERROR;

    return XED_ERROR_NONE;
}


// xed-ild-private.h
xed_bits_t
xed_ild_cvt_mode(xed_machine_mode_enum_t mmode) {

    xed_bits_t result = 0;
    switch(mmode)
    {
      case XED_MACHINE_MODE_LONG_64:
        result = XED_GRAMMAR_MODE_64;

        break;
      case XED_MACHINE_MODE_LEGACY_32:
      case XED_MACHINE_MODE_LONG_COMPAT_32:
        result  = XED_GRAMMAR_MODE_32;
        break;

      case XED_MACHINE_MODE_REAL_16:
      case XED_MACHINE_MODE_LEGACY_16:
      case XED_MACHINE_MODE_LONG_COMPAT_16:
        result = XED_GRAMMAR_MODE_16;
        break;
      default:
        xed_derror("Bad machine mode in xed_ild_cvt_mode() call");
    }
    return result;
}