byteCode

"

    TOS   - top of stack

    NOS   - next on stack

    uu    - byte-valued unsigned (0..16rFF)

    uuuu  - twoByte-valued unsigned (0..16rFFFF); msb-first

    ll    - byte-valued literal index (0..16rFF)

    nn    - byte-valued signed (-128..+127)

    nnnn  - twoByte-valued signed (16r-8000 .. 16r7FFF)

    Notes: 

        - bytecode optimized for space, not interpreter speed,

          since JITTER is assumed to be present and compensate for decoding

          overhead.

        - number assignments due to backward compatible extensions of the

          bytecode set - reassignment & cleanup would be nice.

        - codes marked with (*) make the minimal set; all others duplicate

          the functionality of a minimalSet code, but provides dense encoding

    definition of ST/X byteCode:

    *   00          RET_TOP         return TOS from current context

        01          RET_NIL         return nil from current context

        02          RET_TRUE        return true from current context

        03          RET_FALSE       return false from current context

        04          RET_0           return 0 (zero) from current context

        05          RET_SELF        return the current receiver from current context

    *   06          DUP_OVER        push NOS (used with inlined loops)

    *   07          HOME_RET_TOP    return TOS from home context (method return from block)

        08 uu       LINENO          line number information dummy     

    *   09 uuuu     LINENO16        line number information dummy

        0A          PUSH_NIL        push nil onto stack

        0B          PUSH_TRUE       push true onto stack

        0C          PUSH_FALSE      push false onto stack

        0D          SEND_SELF       self-send

    *   0E ll       PUSH_LIT        push a literal

        0F          PUSH_SELF       push the current receiver onto stack

        10 nn       PUSH_NUM        push a byte-valued smallInteger onto stack

        11 nnnn     PUSH_NUM16      push a twoByte-valued smallInteger onto stack

    *   12          DROP            pop & forget

    *   13          SEND            send 

    *   14          SUPER_SEND      super-send (actually: directed send) 

        15          SEND0           send 0-arg message

        16          SEND1           send 1-arg message

        17          SEND2           send 2-arg message

        18          SEND3           send 3-arg message

        19          SEND_DROP       send & forget result

        1A          SEND0_DROP      send 0-arg message & forget result

        1B          SEND1_DROP      send 1-arg message & forget result

        1C          SEND2_DROP      send 2-arg message & forget result

        1D          SEND3_DROP      send 3-arg message & forget result

    *   1E          PUSH_MARG       push method arg

    *   1F          PUSH_MVAR       push method variable

    *   20          PUSH_BARG       push block arg

    *   21          PUSH_BVAR       push block variable

    *   22          PUSH_IVAR       push instance variable

        23          PUSH_CVAR       -- obsolete -- no longer used.

    *   24          PUSH_GLOB       push global

    *   25          STORE_MVAR      pop and store into method variable

    *   26          STORE_BVAR      pop and store into block variable

    *   27          STORE_IVAR      pop and store into instance variable

        28          STORE_CVAR      -- obsolete -- no longer used.

    *   29          STORE_GLOB      pop and store into global

    *   2A          PUSH_OBARG      push outer block arg (n levels)

        2B          PUSH_OBARG1     push outer block arg (1 level)

        2C          PUSH_OBARG2     push outer block arg (2 levels)

        2D          EQEQ            == -> pop a,b; push a==b

        2E          NENE            ~~ -> pop a,b; push a~~b

    *   2F          DUP             duplicate TOS

        30          EQEQ0           ==0 -> pop a; push a==0

        31          NENE0           ~~0 -> pop a; push a~~0

        32          JMP_FALSE       pop; branch if false

        33          JMP_TRUE        pop; branch if true

        34          JMP_NIL         pop; branch if nil

        35          JMP_NOTNIL      pop; branch if not nil

        36          JMP             branch always

        37          MAKE_BLOCK      make a block

        38          JMP_ZERO        pop; branch if ==0

        39          JMP_NOTZERO     pop; branch if ~~0

        3A          JMP_EQEQ        pop a,b; branch if a==b

        3B          JMP_NENE        pop a,b; branch if a~~b

        3C          JMPL_FALSE      like above, extended branch delta, (add +128/-128 to offs)

        ...          ...

        45          JMPL_NENE       like above, extended branch delta, (add +128/-128 to offs)

        46          JMPVL_FALSE     like above, extended branch delta, (add +256/-256 to offs)

        ...          ...

        4F          JMPVL_NENE      like above, extended branch delta, (add +256/-256 to offs)

        50          PUSH_MVAR1      push method variable 1 (first variable)

        51          PUSH_MVAR2      push method variable 2

        52          PUSH_MVAR3      push method variable 3

        53          PUSH_MVAR4      push method variable 4

        54          PUSH_MVAR5      push method variable 5

        55          PUSH_MVAR6      push method variable 6

        56          PUSH_MARG1      push method arg 1

        57          PUSH_MARG2      push method arg 2

        58          PUSH_MARG3      push method arg 3

        59          PUSH_MARG4      push method arg 4

        5A          PUSH_IVAR1      push inst variable 1 (first variable)

        5B          PUSH_IVAR2      push inst variable 2

        5C          PUSH_IVAR3      push inst variable 3

        5D          PUSH_IVAR4      push inst variable 4

        5E          PUSH_IVAR5      push inst variable 5

        5F          PUSH_IVAR6      push inst variable 6

        60          PUSH_IVAR7      push inst variable 7

        61          PUSH_IVAR8      push inst variable 8

        62          PUSH_IVAR9      push inst variable 9

        63          PUSH_IVAR10     push inst variable 10

        64          STORE_MVAR1     pop and store into method variable 1 (first variable)

        65          STORE_MVAR2     pop and store into method variable 2

        66          STORE_MVAR3     pop and store into method variable 3

        67          STORE_MVAR4     pop and store into method variable 4

        68          STORE_MVAR5     pop and store into method variable 5

        69          STORE_MVAR6     pop and store into method variable 6

        6A          unused

        6B          unused

        6C          unused

        6D          unused

        6E          STORE_IVAR1     pop and store into inst variable 1 (first variable)

        6F          STORE_IVAR2     pop and store into inst variable 2

        70          STORE_IVAR3     pop and store into inst variable 3

        71          STORE_IVAR4     pop and store into inst variable 4

        72          STORE_IVAR5     pop and store into inst variable 5

        73          STORE_IVAR6     pop and store into inst variable 6

        74          STORE_IVAR7     pop and store into inst variable 7

        75          STORE_IVAR8     pop and store into inst variable 8

        76          STORE_IVAR9     pop and store into inst variable 9

        77          STORE_IVAR10    pop and store into inst variable 10

        78          PUSH_0          push smallinteger 0 constant

        79          PUSH_1          push smallinteger 1 constant

        7A          PUSH_M1         push smallinteger -1 constant

        7B          SEND_PLUS1      send + 1 to TOS; replace TOS by result

        7C          SEND_MINUS1     send - 1 to TOS; replace TOS by result

        7D          INC_MVAR        send + 1 to a method variable; store result into mvar

        7E          DEC_MVAR        send - 1 to a method variable; store result into mvar

        7F nn       RET_NUM         return a smallInteger from current context

    *   80          PUSH_OBVAR      push outer block variable

    *   81          STORE_OBVAR     pop and store into outer block variable

        82          SEND_EQ         130     /* send = */

        83          SEND_PLUS       131     /* send + */

        84          SEND_NE         132     /* send ~= */

        85          SEND_MINUS      133     /* send - */

        86          SEND_CLASS      134     /* send class */

        87          SEND_AT         135     /* send at:*/

        88          SEND_ATPUT      136     /* send at:put: */

        89          SEND_BITAND     137     /* send bitAnd: */

        8A          SEND_BITOR      138     /* send bitOr: */

        8B          PUSH_2          139     /* push constant 2 */

        8C          PUSH_BARG1      140     /* push block argument */

        8D          PUSH_BARG2      141

        8E          PUSH_BARG3      142

        8F          PUSH_BARG4      143

    *   90          PUSH_CONTEXT    144

        91          SEND_GT         145     /* send > */

        92          SEND_GE         146     /* send >= */

        93          SEND_LT         147     /* send < */

        94          SEND_LE         148     /* send <= */

        95          UNUSED_149      149     /* was: send next */

        96          UNUSED_150      150     /* was: send peek */

        97          SEND_VALUE      151     /* send value */

        98          SEND_VALUE1     152     /* send value: */

        99          SEND_SIZE       153     /* send size */

        9A          UNUSED_154      154

        9B          UNUSED_155      155

        9C          MK0BLOCK        156     

        9D          MKNILBLOCK      157

        9E          UNUSED_158      158     /* was: send asInteger */

        9F          UNUSED_159      159     /* was: send rounded */

        A0          RET_MVAR1       160     /* return method variable */

        A1          RET_MVAR2       161

        A2          RET_MVAR3       162

        A3          RET_MVAR4       163

        A4          RET_MVAR5       164

        A5          RET_MVAR6       165

        A6          RET_IVAR1       166     /* return instance variable */

        A7          RET_IVAR2       167

        A8          RET_IVAR3       168

        A9          RET_IVAR4       169

        AA          RET_IVAR5       170

        AB          RET_IVAR6       171

        AC          RET_IVAR7       172

        AD          RET_IVAR8       173

        AE          RET_MARG1       174

        AF          RET_MARG2       175

        B0          PUSH_CIVAR      176     /* push class instance variable */

        B1          STORE_CIVAR     177     /* store top of stack in class instance variable */

        B2          SEND_VALUE2     178     /* send value:value: */

        B3          SEND_NOT        179     

        B4          SEND_SELF0      180     /* send a 0-arg message to self */

        B5          SEND_SELF1      181     /* send a 1-arg message to self */

        B6          SEND_SELF2      182     /* send a 2-arg message to self */

        B7          SEND_SELF3      183     /* send a 3-arg message to self */

        B8          SEND_SELF_DROP0 184     /* send a 0-arg message to self forget result */

        B9          SEND_SELF_DROP1 185     /* send a 1-arg message to self forget result */

        BA          SEND_SELF_DROP2 186     /* send a 2-arg message to self forget result */

        BB          SEND_SELF_DROP3 187     /* send a 3-arg message to self forget result */

        BC          ISNIL           188     

        BD          NOTNIL          189     

#define JMPA_FALSE      190     /* jumps to absolute offset (2 byte hi-lo) */

#define JMPA_TRUE       191

#define JMPA_NIL        192

#define JMPA_NOTNIL     193

#define JMPA            194

#define MAKE_ABLOCK     195

#define JMPA_ZERO       196

#define JMPA_NOTZERO    197

#define JMPA_EQ         198

#define JMPA_NOTEQ      199

#define PUSH_GSPECIAL   200     /* push special global */

# define GSPECIAL_ARRAY                 0

# define GSPECIAL_STRING                1

# define GSPECIAL_FLOATARRAY            2

# define GSPECIAL_DOUBLEARRAY           3

# define GSPECIAL_POINT                 4

# define GSPECIAL_SYMBOL                5

# define GSPECIAL_SMALLTALK             6

# define GSPECIAL_PROCESSOR             7

# define GSPECIAL_SMALLINTEGER          8

# define GSPECIAL_CHARACTER             9

# define GSPECIAL_FLOAT                 10

# define GSPECIAL_PROCESS               11

# define GSPECIAL_SET                   12

# define GSPECIAL_IDENTITYSET           13

# define GSPECIAL_DICTIONARY            14

# define GSPECIAL_IDENTITYDICTIONARY    15

# define GSPECIAL_SEMAPHORE             16

# define GSPECIAL_ORDEREDCOLLECTION     17

    *   PUSH_LLIT       201     /* push a literal (2-byte literal-number)*/

#define JMP_FALSE_L     202     /* jump if top is false (+127 .. -128) */

#define JMP_TRUE_L      203     /* jump if top is true */

#define UNUSED_204      204

#define LSEND_MSG       205     /* send with 16 bit literal index */

#define LSUPERSEND_MSG  206     /* send with 16 bit literal index */

#define LSEND_SELF      207     /* send with 16 bit literal index */

#define PUSH_GT0        208

#define UNUSED_209      209

#define SEND_ARRAY_NEW  210     /* use for new/basicNew; top is size (0 for Array new) */

#define SEND_BASICNEW   211     /* top is class (receiver) */

#define SEND_GT0        212     /* send > 0 */

#define SEND_NEW        213     /* top is class (receiver) */

#define SEND_BASICNEWN  214     /* top is class (receiver) and arg */

#define SEND_NEWN       215     /* top is class (receiver) and arg */

#define SEND_LOGAND     216     /* send & */

#define SEND_LOGOR      217     /* send | */

#define PUSH_LGLOB      218     /* push global variable word index literal */

#define STORE_LGLOB     219     /* store global with word index literal */

#define UNUSED_220      220

#define UNUSED_221      221

#define PUSH_LIT1       222     /* push 1st literal */

#define PUSH_LIT2       223     /* push 2nd literal */

#define PUSH_LIT3       224     /* push literal 3 */

#define PUSH_LIT4       225     /* push literal 4 */

#define PUSH_LIT5       226     /* push literal 5 */

#define PUSH_LIT6       227     /* push literal 6 */

#define PUSH_LIT7       228     /* push literal 7 */

#define PUSH_LIT8       229     /* push literal 8 */

#define SEND_MUL        230     /* send * */

#define SEND_SPECIAL    231     /* special send */

# define SPECIAL_TOP    0

# define SPECIAL_BOTTOM 1

# define SPECIAL_LEFT   2

# define SPECIAL_RIGHT  3

# define SPECIAL_X      4

# define SPECIAL_Y      5

# define SPECIAL_WIDTH  6

# define SPECIAL_HEIGHT 7

# define SPECIAL_ORIGIN 8

# define SPECIAL_EXTENT 9

# define SPECIAL_ASINTEGER 10

# define SPECIAL_ROUNDED   11

# define SPECIAL_NEXT      12

# define SPECIAL_PEEK      13

#define PUSH_BVAR1      232

#define PUSH_BVAR2      233

#define PUSH_BVAR3      234

#define STORE_BVAR1     235

#define STORE_BVAR2     236

#define STORE_BVAR3     237

#define BLOCK_REF       238

#define PUSH_LVAR       239     /* push local variable 0..numArgs-1 for args; numArgs..numArgs+nLocal-1 for mVars */

#define STORE_LVAR      240     /* store local variable 0..numArgs-1 for args; numArgs..numArgs+nLocal-1 for mVars */

#define UNUSED_241      241

#define UNUSED_242      242

#define UNUSED_243      243

#define UNUSED_244      244

#define UNUSED_245      245

#define UNUSED_246      246

#define UNUSED_247      247

#define UNUSED_248      248

#define UNUSED_249      249

#define UNUSED_250      250

#define UNUSED_251      251

#define UNUSED_252      252

#define UNUSED_253      253

#define UNUSED_254      254

#define UNUSED_255      255

    [author:]

        Claus Gittinger

"

!