Initial commit

SBC/bytecode.md

@@ -0,0 +1,116 @@
+# Slang Bytecode
+
+
+## Standalone
+
+### NOP
+0x00
+> Does nothing.
+### RET
+0x01
+> Returns `TOS` to caller.
+
+
+## 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`.
+### FLRDIV
+0x24
+> Pushes `TOS1 // TOS`.
+### MOD
+0x25
+> Pushes `TOS1 % TOS`.
+### POW
+0x26
+> Pushes `TOS1 ** TOS`.
+### SHL
+0x27
+> Pushes `TOS1 << TOS`.
+### SHR
+0x28
+> Pushes `TOS1 >> TOS`.
+### AND
+0x29
+> Pushes `TOS1 & TOS`.
+### OR
+0x2a
+> Pushes `TOS1 | TOS`.
+### XOR
+0x2b
+> Pushes `TOS1 ^ TOS`.
+
+
+## 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
+> Pops `nargs ^ (1 << 7)` TODO