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64-Bit State Execution Register

The StateExecutionUnit type is declared as a transparent wrapper over an unsigned 64-bit integer:

#![allow(unused)]
fn main() {
#[repr(transparent)]
#[derive(Clone, Copy, Debug, PartialEq, Eq)]
pub struct StateExecutionUnit(pub u64);
}

Detailed Bit-Range Allocation

Bit RangeField NameTypeCanonical EncodingPurpose
0..7ROLE_MASKu8Bitfield (1 << bit)Single-hot authorized role mask
8..15STATUS_FLAGSu8BitfieldOperational state of the state machine
16..23CURRENT_NODEu8Scalar $[0, 255]$Current state coordinate ($S_i$)
24..31TARGET_NODEu8Scalar $[0, 255]$Committed next state coordinate ($S_{i+1}$)
32..47EPOCH_SLOTu16Scalar $[0, 65535]$16-bit temporal anchor (slot & 0xFFFF)
48..63TOPOLOGY_FLAGSu16BitfieldStructural graph constraints

Field Specifications

1. Role Authorization (bits 0..7)

Defines the authorized caller roles for state mutation:

  • ROLE_SWAP (1 << 0 = 0x01): Token and asset swaps
  • ROLE_BUY_NFT (1 << 1 = 0x02): NFT acquisition & minting
  • ROLE_ORACLE_UPDATE (1 << 2 = 0x04): Price and state attestations
  • ROLE_GOVERNANCE (1 << 3 = 0x08): Parameter reconfiguration
  • ROLE_DRAIN (1 << 4 = 0x10): Emergency recovery drainage
  • ROLE_FLASHLOAN (1 << 5 = 0x20): Uncollateralized single-slot liquidity

Single-Hot Enforcement: A requested role is valid if and only if exactly one bit is set (popcount(role) == 1). Multi-bit role injection is rejected in constant time via (r & (r - 1)) != 0.

2. Operational Status (bits 8..15)

  • STATUS_ACTIVE (1 << 8 = 0x0100): State machine is operational.
  • STATUS_PAUSED (1 << 9 = 0x0200): Invariant circuit breaker triggered; all mutations blocked.
  • STATUS_RATE_LIMITED (1 << 10 = 0x0400): Temporal throttle active.
  • FLAG_RING_TOPOLOGY (1 << 15 = 0x8000): Permitted torus/ring wrap-around ($S_n \to S_0$).

3. FSM Coordinates (bits 16..31)

Encodes the current position $S_i$ and the valid target position $S_{i+1}$. Under default DAG rules: $$S_{i+1} > S_i$$

4. Slot Window Anchor (bits 32..47)

Tracks the lower 16 bits of the Solana slot counter (slot & 0xFFFF). Protects against transaction replay, slot drift, and same-slot re-entrancy attacks.

5. Topology Flags (bits 48..63)

  • FLAG_ACYCLIC (1 << 48): Enforces strict monotonically increasing topological ordering.
  • FLAG_NO_SELF_LOOP (1 << 49): Strictly forbids $S_{i+1} = S_i$.