Slang/SBC/bytecode.md

Slang Bytecode

Standalone

NOP

0x00

Does nothing.

END

0x01

Closes previously opened block.

POP

0x02

Drops TOS.

RET

0x03

Returns TOS to caller.

BLTIN

0x04

Reads string from the bytecode until null byte (max 255 bytes) and pushes builtin function with that name.

CODE

0x05

Reads code from the bytecode until the corresponding END instruction and pushes a reference to it and then its length. Opens a block.

Unary

POS

0x10

Pushes abs(TOS).

NEG

0x11

Pushes -TOS.

NOT

0x12

Pushes !TOS.

INV

0x13

Pushes ~TOS.

ATOI

0x14

Pushes integer of smallest possible width parsed from string TOS.

ITOA

0x15

Pushes string representation of integer TOS.

ITOF

0x16

Pushes real of smallest possible width equal to integer TOS.

CEIL

0x17

Pushes smallest integer of smallest possible width greater or equal to real TOS.

FLR

0x18

Pushes largest integer of smallest possible width less or equal to real TOS.

RND

0x19

Pushes integer of smallest possible width equal to rounded TOS.

CTOS

0x1A

Pushes string consisting of char TOS and a null byte.

Binary

ADD

0x20

Pushes TOS1 + TOS.

SUB

0x21

Pushes TOS1 - TOS.

MUL

0x22

Pushes TOS1 * TOS.

DIV

0x23

Pushes TOS1 / TOS.

IDIV

0x24

Pushes TOS1 // TOS.

MOD

0x25

Pushes TOS1 % TOS.

POW

0x26

Pushes TOS1 ** TOS.

LSH

0x27

Pushes TOS1 << TOS.

RSH

0x28

Pushes TOS1 >> TOS.

AND

0x29

Pushes TOS1 & TOS.

OR

0x2A

Pushes TOS1 | TOS.

XOR

0x2B

Pushes TOS1 ^ TOS.

Comparisons

EQ

0x30

Pushes TOS1 == TOS.

NE

0x31

Pushes TOS1 != TOS.

LT

0x32

Pushes TOS1 < TOS.

GT

0x33

Pushes TOS1 > TOS.

LE

0x34

Pushes TOS1 <= TOS.

GE

0x35

Pushes TOS1 >= TOS.

IS

0x36

Pushes TOS1 is TOS.

ISNOT

0x37

Pushes TOS1 is not TOS.

Flow control

IF

0x40

If TOS is false, skips bytecode until corresponding ELSE (if exists) or END. Opens a block.

ELSE

0x41

Pops last IF result from IF-stack, and if it is true, skips bytecode to corresponding END. Opens a block.

EXEC

0x42

Executes code block TOS1 of length TOS and pushes the result.

With argument

ALLOC*(bytes)*

0xA0

Pushes reference to calloc(1, bytes).

EXTEND*(bytes)*

0xA1

Extends integer TOS width to bytes bytes if narrower.

CONST*(bytes)*

0xA2

Reads next bytes bytes of bytecode and pushes a reference to a copy of them.

JUMPF*(offset)*

0xA3

Jumps offset bytes of bytecode forward.

JUMPB*(offset)*

0xA4

Jumps offset bytes of bytecode backward.

SCPGET*(cell)*

0xA5

Pushes the value of cell cell of local scope variables array.

SCPSET*(cell)*

0xA6

Sets the value of cell cell of local scope variables array to TOS.

CALL*(nargs)*

0xA7

Calls TOS with nargs arguments popped from stack (below the callable).