Skip to content

opcodes.md

Latest commit

 

History

History
173 lines (154 loc) · 6.24 KB

opcodes.md

File metadata and controls

173 lines (154 loc) · 6.24 KB

Pathologic Script VM Opcodes

Instruction Format

Each instruction begins with a 1-byte opcode. Operands follow as uint32/int32/uint8/float depending on the opcode. Instructions are variable-length (1-17 bytes).

Type Tags

  • 1 = bool
  • 2 = int
  • 3 = float
  • 4 = string
  • 5 = object
  • 6 = cvector (3 floats)

Opcode Table

Move / Load Constants (0x00-0x0D)

Op Name Operands Description
0x00 Mov dst:u32, src:u32 Stack[-dst] = Stack[-src]
0x01 MovB dst:u32, val:u8 Stack[-dst] = (bool)val
0x02 MovI dst:u32, val:i32 Stack[-dst] = (int)val
0x03 MovF dst:u32, val:f32 Stack[-dst] = (float)val
0x04 MovS dst:u32, pool_off:u32 Stack[-dst] = string from pool
0x05 MovV dst:u32, x:f32, y:f32, z:f32 Stack[-dst] = CVector(x,y,z)
0x06 MovT src:u32, dst:u32 Stack[-dst] = TaskVar[src]
0x07 TMov src:u32, dst:u32 TaskVar[dst] = Stack[-src]
0x08 TMovB dst:u32, val:u8 TaskVar[dst] = (bool)val
0x09 TMovI dst:u32, val:i32 TaskVar[dst] = (int)val
0x0A TMovF dst:u32, val:f32 TaskVar[dst] = (float)val
0x0B TMovS dst:u32, pool_off:u32 TaskVar[dst] = string from pool
0x0C TMovV dst:u32, x:f32, y:f32, z:f32 TaskVar[dst] = CVector(x,y,z)
0x0D TMovT src:u32, dst:u32 TaskVar[dst] = TaskVar[src]

Control Flow (0x0E-0x0F)

Op Name Operands Description
0x0E Jump target:u32 Unconditional jump to bytecode offset
0x0F JumpB var:u32, target:u32, cond:u8, pop:u16 Conditional branch + pop

Stack Operations (0x10-0x1E)

Op Name Operands Description
0x10 Push var:u32 Push Stack[-var] onto stack
0x11 PushB val:u8 Push bool literal
0x12 PushI val:i32 Push int literal
0x13 PushF val:f32 Push float literal
0x14 PushS pool_off:u32 Push string from pool
0x15 PushT var:u32 Push TaskVar[var]
0x16 PushVec x:f32, y:f32, z:f32 Push CVector literal
0x17 PushV count:u32 Allocate count stack slots (local vars)
0x18 PushE count:u32 Push event vars
0x19 PushGE count:u32 Push global event vars
0x1A Pop count:u32 Pop count stack slots
0x1B PopE count:u32 Pop event vars
0x1C PopGE count:u32 Pop global event vars
0x1D SetNull var:u32 Stack[-var] = null
0x1E SetNullT var:u32 TaskVar[var] = null

Arithmetic (0x1F-0x23) — Pop 2, push result

Op Name Description
0x1F Add a + b
0x20 Sub a - b
0x21 Mult a * b
0x22 Div a / b
0x23 Mod a % b

Logic / Comparison (0x24-0x2E) — Pop 2, push result

Op Name Description
0x24 And a && b
0x25 Or a || b
0x26 Xor a ^ b
0x27 Eq a == b
0x28 Neq a != b
0x29 LT a < b
0x2A GT a > b
0x2B LE a <= b
0x2C GE a >= b
0x2D NullEq a == null
0x2E NullNeq a != null

Unary (0x2F-0x30) — Pop 1, push result

Op Name Description
0x2F Neg -a
0x30 Not !a

In-place Arithmetic (0x31-0x35) — Modify Stack[-dst] with popped operand

Op Name Description
0x31 Add2 Stack[-dst] += popped
0x32 Sub2 Stack[-dst] -= popped
0x33 Mult2 Stack[-dst] *= popped
0x34 Div2 Stack[-dst] /= popped
0x35 Mod2 Stack[-dst] %= popped

In-place Logic / Comparison (0x36-0x42) — Modify Stack[-dst]

Op Name Description
0x36 And2 &=
0x37 Or2 |=
0x38 Xor2 ^=
0x39 Eq2 == (in-place)
0x3A Neq2 != (in-place)
0x3B LT2 < (in-place)
0x3C GT2 > (in-place)
0x3D LE2 <= (in-place)
0x3E GE2 >= (in-place)
0x3F NullEq2 == null (in-place)
0x40 NullNeq2 != null (in-place)
0x41 Neg2 Negate in-place
0x42 Not2 Logical not in-place

Math Functions (0x43-0x4C) — Unary math, Pop/In-place variants

Op Name Description
0x43 Sqrt sqrt(a) — pop 1, push result
0x44 Sqrt2 sqrt in-place
0x45 Sin sin(a)
0x46 Sin2 sin in-place
0x47 Cos cos(a)
0x48 Cos2 cos in-place
0x49 ASin asin(a)
0x4A ASin2 asin in-place
0x4B Pow pow(a, b)
0x4C Pow2 pow in-place

Function Calls & Control (0x4D+) — Version-dependent

Alpha version (IS_ALPHA = True):

Op Name Description
0x4D Call Call subroutine
0x4E Return Return from subroutine
0x4F TaskCall Call task function
0x50 TaskReturn Return from task
0x51 Func Call native function by name
0x52 ObjFunc Call object method
0x53 TObjFunc Call object method (task variant)
0x54 EventEnable Enable event handler
0x55 EventDisable Disable event handler
0x56 FuncExist Check if function exists
0x57 FuncExist2 Check if function exists (variant)

HD version (IS_ALPHA = False) — 2 extra opcodes at 0x4D-0x4E:

Op Name Description
0x4D CString Convert to char string
0x4E CString2 Convert to char string (variant)
0x4F (new_2) Unknown HD-only instruction
0x50 Return Return from subroutine
0x51 TaskCall Call task function
0x52 TaskReturn Return from task
0x53 Func Call native function by name
0x54 ObjFunc Call object method
0x55 TObjFunc Call object method (task variant)
0x56 EventEnable Enable event handler
0x57 EventDisable Disable event handler
0x58 FuncExist Check if function exists
0x59 FuncExist2 Check if function exists (variant)

Notes

  • Opcodes 0x00-0x4C are identical between alpha and HD
  • HD inserts CString/CString2 at 0x4D-0x4E, shifting Call+ by +2
  • The assembler handles this via is_alpha flag
  • Stack addressing: negative offsets (Stack[-N]) are relative to current stack top
  • Task vars: Stack[I + Tasks[-1].StackPointer] — separate task variable area
  • All string references use byte offsets into the DataPool