unit DasmMSIL;
(*
The MSIL disassembler main module of the DCU32INT utility
by Alexei Hmelnov.
----------------------------------------------------------------------------
E-Mail: alex@icc.ru
http://hmelnov.icc.ru/DCU/
----------------------------------------------------------------------------

See the file "readme.txt" for more details.

------------------------------------------------------------------------
                             IMPORTANT NOTE:
This software is provided 'as-is', without any expressed or implied warranty.
In no event will the author be held liable for any damages arising from the
use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:
1. The origin of this software must not be misrepresented, you must not
   claim that you wrote the original software.
2. Altered source versions must be plainly marked as such, and must not
   be misrepresented as being the original software.
3. This notice may not be removed or altered from any source
   distribution.
*)
interface

uses
  DasmDefs,FixUp;

type
  PMSILHeader = ^TMSILHeader;
  TMSILHeader = packed record
    F,F1: Word;
    CodeSz: Cardinal;
    L1: LongInt;
  end ;

procedure SetMSILDisassembler;

implementation

uses
  DCU_In,DCU_Out;

const
 {Command argument type}
  atVoid = 0;
  atU1 = 1;
  atU2 = 2;
  atU4 = 3;
  atI1 = 4;
  atI4 = 5;
  atI8 = 6;
  atR4 = 7;
  atR8 = 8;
  atMetadata = 9;
  atCheckKind = 10;
  atJmpofs1 = 11;
  atJmpofs4 = 12;
  atJmpofs4tbl =13;
  atExtTbl = 14;

  atMask = $0F;

 {Command Kind}
  ckPrefix = $80;
  ckStop = $40; //Stops command sequence

const
  argszVariable = -1;
  argszWrong = -2;

  CmdArgSize: array[0..atMask]of integer = (
    0{atVoid = 0},1{atU1 = 1},2{atU2 = 2},4{atU4 = 3},
    1{atI1 = 4},4{atI4 = 5},8{atI8 = 6},4{atR4 = 7},
    8{atR8 = 8},4{atMetadata = 9},1{atCheckKind = 10},1{atJmpofs1 = 11},
    4{atJmpofs4 = 12},argszVariable{atJmpofs4tbl=13},argszVariable{atExtTbl = 14},
    argszWrong);

MetadataTbl: array[$00..$2C] of PChar = (
  'Module' {0x00},
  'TypeRef' {0x01},
  'TypeDef' {0x02},
  '',
  'Field' {0x04},
  '',
  'MethodDef' {0x06},
  '',
  'Param' {0x08},
  'InterfaceImpl' {0x09},
  'MemberRef' {0x0A},
  'Constant' {0x0B},
  'CustomAttribute' {0x0C},
  'FieldMarshal' {0x0D},
  'DeclSecurity' {0x0E},
  'ClassLayout' {0x0F},
  'FieldLayout' {0x10},
  'StandAloneSig' {0x11},
  'EventMap' {0x12},
  '',
  'Event' {0x14},
  'PropertyMap' {0x15},
  '',
  'Property' {0x17},
  'MethodSemantics' {0x18},
  'MethodImpl' {0x19},
  'ModuleRef' {0x1A},
  'TypeSpec' {0x1B},
  'ImplMap' {0x1C},
  'FieldRVA' {0x1D},
  '',
  '',
  'Assembly' {0x20},
  'AssemblyProcessor' {0x21},
  'AssemblyOS' {0x22},
  'AssemblyRef' {0x23},
  'AssemblyRefProcessor' {0x24},
  'AssemblyRefOS' {0x25},
  'File' {0x26},
  'ExportedType' {0x27},
  'ManifestResource' {0x28},
  'NestedClass' {0x29},
  'GenericParam' {0x2A},
  'MethodSpec' {0x2B},
  'GenericParamConstraint' {0x2C}
);

CheckKindTbl: array[$0..$2] of PChar = (
  'typecheck'{0x1},
  'rangecheck'{0x2},
  'nullcheck'{0x4});

type
  PCmdInfo = ^TCmdInfo;
  TCmdInfo = record
    Name: PChar;
    F: integer;
  end ;

  PCmdInfoTbl = ^TCmdInfoTbl;
  TCmdInfoTbl = array[byte]of TCmdInfo;

  PStrTbl = ^TStrTbl;
  TStrTbl = array[byte]of PChar;

const
  CmdTblFE: array[0..$1E] of TCmdInfo = (
    (Name: 'arglist'; {0x00}),
    (Name: 'ceq'; {0x01}),
    (Name: 'cgt'; {0x02}),
    (Name: 'cgt_un'; {0x03}),
    (Name: 'clt'; {0x04}),
    (Name: 'clt_un'; {0x05}),
    (Name: 'ldftn'; F: atMetadata {0x06}),
    (Name: 'ldvirtftn'; F: atMetadata {0x07}),
    (Name: ''; {0x08}),
    (Name: 'ldarg'; {0x09}),
    (Name: 'ldarga'; {0x0A}),
    (Name: 'starg'; {0x0B}),
    (Name: 'ldloc'; {0x0C}),
    (Name: 'ldloca'; {0x0D}),
    (Name: 'stloc'; {0x0E}),
    (Name: 'localloc'; {0x0F}),
    (Name: ''; {0x10}),
    (Name: 'endfilter'; {0x11}),
    (Name: 'unaligned_'; F: atU1 or ckPrefix {0x12}), //prefix - operand may be not aligned on alignment specified
    (Name: 'volatile_'; F: ckPrefix {0x13}), //prefix
    (Name: 'tail_'; F: ckPrefix or ckStop{0x14}), //call terminates current method (like Halt or raise)
    (Name: 'initobj'; F: atMetadata {0x15}),
    (Name: 'constrained_'; F: atMetadata or ckPrefix {0x16}), //prefix for callvirt
    (Name: 'cpblk'; {0x17}),
    (Name: 'initblk'; {0x18}),
    (Name: 'no_'; F: atCheckKind or ckPrefix {0x19}), //prefix - skip check
    (Name: 'rethrow'; {0x1A}),
    (Name: ''; {0x1B}),
    (Name: 'sizeof'; F: atMetadata {0x1C}),
    (Name: 'refanytype'; {0x1D}),
    (Name: 'readonly_'; F: ckPrefix {0x1E}) //prefix
  );


  CmdTbl: array[byte] of TCmdInfo = (
    (Name: 'nop'; {0x00}),
    (Name: 'break'; F: ckStop {0x01}),
    (Name: 'ldarg_0'; {0x02}),
    (Name: 'ldarg_1'; {0x03}),
    (Name: 'ldarg_2'; {0x04}),
    (Name: 'ldarg_3'; {0x05}),
    (Name: 'ldloc_0'; {0x06}),
    (Name: 'ldloc_1'; {0x07}),
    (Name: 'ldloc_2'; {0x08}),
    (Name: 'ldloc_3'; {0x09}),
    (Name: 'stloc_0'; {0x0A}),
    (Name: 'stloc_1'; {0x0B}),
    (Name: 'stloc_2'; {0x0C}),
    (Name: 'stloc_3'; {0x0D}),
    (Name: 'ldarg_s'; F: atU1 {0x0E}),
    (Name: 'ldarga_s'; F: atU1 {0x0F}),
    (Name: 'starg_s'; F: atU1 {0x10}),
    (Name: 'ldloc_s'; F: atU1 {0x11}),
    (Name: 'ldloca_s'; F: atU1 {0x12}),
    (Name: 'stloc_s'; F: atU1 {0x13}),
    (Name: 'ldnull'; {0x14}),
    (Name: 'ldc_i4_m1'; {0x15}),
    (Name: 'ldc_i4_0'; {0x16}),
    (Name: 'ldc_i4_1'; {0x17}),
    (Name: 'ldc_i4_2'; {0x18}),
    (Name: 'ldc_i4_3'; {0x19}),
    (Name: 'ldc_i4_4'; {0x1A}),
    (Name: 'ldc_i4_5'; {0x1B}),
    (Name: 'ldc_i4_6'; {0x1C}),
    (Name: 'ldc_i4_7'; {0x1D}),
    (Name: 'ldc_i4_8'; {0x1E}),
    (Name: 'ldc_i4_s'; F: atI1 {0x1F}),
    (Name: 'ldc_i4'; F: atI4 {0x20}),
    (Name: 'ldc_i8'; F: atI8 {0x21}),
    (Name: 'ldc_r4'; F: atR4 {0x22}),
    (Name: 'ldc_r8'; F: atR8 {0x23}),
    (Name: ''; {0x24}),
    (Name: 'dup'; {0x25}),
    (Name: 'pop'; {0x26}),
    (Name: 'jmp'; F: atMetadata or ckStop{0x27}),
    (Name: 'call'; F: atMetadata {0x28}),
    (Name: 'calli'; F: atMetadata {0x29}),
    (Name: 'ret'; F: ckStop {0x2A}),
    (Name: 'br_s'; F: atJmpofs1 or ckStop {0x2B}),
    (Name: 'brfalse_s'; F: atJmpofs1 {0x2C}),
    (Name: 'brtrue_s'; F: atJmpofs1 {0x2D}),
    (Name: 'beq_s'; F: atJmpofs1 {0x2E}),
    (Name: 'bge_s'; F: atJmpofs1 {0x2F}),
    (Name: 'bgt_s'; F: atJmpofs1 {0x30}),
    (Name: 'ble_s'; F: atJmpofs1 {0x31}),
    (Name: 'blt_s'; F: atJmpofs1 {0x32}),
    (Name: 'bne_un_s'; F: atJmpofs1 {0x33}),
    (Name: 'bge_un_s'; F: atJmpofs1 {0x34}),
    (Name: 'bgt_un_s'; F: atJmpofs1 {0x35}),
    (Name: 'ble_un_s'; F: atJmpofs1 {0x36}),
    (Name: 'blt_un_s'; F: atJmpofs1 {0x37}),
    (Name: 'br'; F: atJmpofs4 or ckStop {0x38}),
    (Name: 'brfalse'; F: atJmpofs4 {0x39}),
    (Name: 'brtrue'; F: atJmpofs4 {0x3A}),
    (Name: 'beq'; F: atJmpofs4 {0x3B}),
    (Name: 'bge'; F: atJmpofs4 {0x3C}),
    (Name: 'bgt'; F: atJmpofs4 {0x3D}),
    (Name: 'ble'; F: atJmpofs4 {0x3E}),
    (Name: 'blt'; F: atJmpofs4 {0x3F}),
    (Name: 'bne_un'; F: atJmpofs4 {0x40}),
    (Name: 'bge_un'; F: atJmpofs4 {0x41}),
    (Name: 'bgt_un'; F: atJmpofs4 {0x42}),
    (Name: 'ble_un'; F: atJmpofs4 {0x43}),
    (Name: 'blt_un'; F: atJmpofs4 {0x44}),
    (Name: 'switch'; F: atJmpofs4tbl {0x45}),
    (Name: 'ldind_i1'; {0x46}),
    (Name: 'ldind_u1'; {0x47}),
    (Name: 'ldind_i2'; {0x48}),
    (Name: 'ldind_u2'; {0x49}),
    (Name: 'ldind_i4'; {0x4A}),
    (Name: 'ldind_u4'; {0x4B}),
    (Name: 'ldind_i8'; {0x4C}),
    (Name: 'ldind_i'; {0x4D}),
    (Name: 'ldind_r4'; {0x4E}),
    (Name: 'ldind_r8'; {0x4F}),
    (Name: 'ldind_ref'; {0x50}),
    (Name: 'stind_ref'; {0x51}),
    (Name: 'stind_i1'; {0x52}),
    (Name: 'stind_i2'; {0x53}),
    (Name: 'stind_i4'; {0x54}),
    (Name: 'stind_i8'; {0x55}),
    (Name: 'stind_r4'; {0x56}),
    (Name: 'stind_r8'; {0x57}),
    (Name: 'add'; {0x58}),
    (Name: 'sub'; {0x59}),
    (Name: 'mul'; {0x5A}),
    (Name: 'div'; {0x5B}),
    (Name: 'div_un'; {0x5C}),
    (Name: 'rem'; {0x5D}),
    (Name: 'rem_un'; {0x5E}),
    (Name: 'and'; {0x5F}),
    (Name: 'or'; {0x60}),
    (Name: 'xor'; {0x61}),
    (Name: 'shl'; {0x62}),
    (Name: 'shr'; {0x63}),
    (Name: 'shr_un'; {0x64}),
    (Name: 'neg'; {0x65}),
    (Name: 'not'; {0x66}),
    (Name: 'conv_i1'; {0x67}),
    (Name: 'conv_i2'; {0x68}),
    (Name: 'conv_i4'; {0x69}),
    (Name: 'conv_i8'; {0x6A}),
    (Name: 'conv_r4'; {0x6B}),
    (Name: 'conv_r8'; {0x6C}),
    (Name: 'conv_u4'; {0x6D}),
    (Name: 'conv_u8'; {0x6E}),
    (Name: 'callvirt'; F: atMetadata {0x6F}),
    (Name: 'cpobj'; F: atMetadata {0x70}),
    (Name: 'ldobj'; F: atMetadata {0x71}),
    (Name: 'ldstr'; F: atMetadata {0x72}),
    (Name: 'newobj'; F: atMetadata {0x73}),
    (Name: 'castclass'; F: atMetadata {0x74}),
    (Name: 'isinst'; F: atMetadata {0x75}),
    (Name: 'conv_r_un'; {0x76}),
    (Name: ''; {0x77}),
    (Name: ''; {0x78}),
    (Name: 'unbox'; F: atMetadata {0x79}),
    (Name: 'throw'; F: ckStop {0x7A}),
    (Name: 'ldfld'; F: atMetadata {0x7B}),
    (Name: 'ldflda'; F: atMetadata {0x7C}),
    (Name: 'stfld'; F: atMetadata {0x7D}),
    (Name: 'ldsfld'; F: atMetadata {0x7E}),
    (Name: 'ldsflda'; F: atMetadata {0x7F}),
    (Name: 'stsfld'; F: atMetadata {0x80}),
    (Name: 'stobj'; F: atMetadata {0x81}),
    (Name: 'conv_ovf_i1_un'; {0x82}),
    (Name: 'conv_ovf_i2_un'; {0x83}),
    (Name: 'conv_ovf_i4_un'; {0x84}),
    (Name: 'conv_ovf_i8_un'; {0x85}),
    (Name: 'conv_ovf_u1_un'; {0x86}),
    (Name: 'conv_ovf_u2_un'; {0x87}),
    (Name: 'conv_ovf_u4_un'; {0x88}),
    (Name: 'conv_ovf_u8_un'; {0x89}),
    (Name: 'conv_ovf_i_un'; {0x8A}),
    (Name: 'conv_ovf_u_un'; {0x8B}),
    (Name: 'box'; F: atMetadata {0x8C}),
    (Name: 'newarr'; F: atMetadata {0x8D}),
    (Name: 'ldlen'; {0x8E}),
    (Name: 'ldelema'; F: atMetadata {0x8F}),
    (Name: 'ldelem_i1'; {0x90}),
    (Name: 'ldelem_u1'; {0x91}),
    (Name: 'ldelem_i2'; {0x92}),
    (Name: 'ldelem_u2'; {0x93}),
    (Name: 'ldelem_i4'; {0x94}),
    (Name: 'ldelem_u4'; {0x95}),
    (Name: 'ldelem_i8'; {0x96}),