Crate essential_vm

The essential VM implementation.

Reading State

The primary entrypoint for this crate is the Vm type.

The Vm allows for executing arbitrary essential ASM ops. The primary use-case is executing Programs that make up a Predicate’s program graph during Solution validation.

Executing Ops

There are three primary methods available for executing operations:

• Vm::exec_ops
• Vm::exec_bytecode
• Vm::exec_bytecode_iter

Each have slightly different performance implications, so be sure to read the docs before selecting a method.

Execution Future

The Vm::exec_* functions all return Futures that not only yield on async operations, but yield based on a user-specified gas limit too. See the ExecFuture docs for further details on the implementation.

Re-exports

pub use essential_types as types;

Modules

asm

Assembly for the Essential VM.

bytecode

Items related to bytecode representation for the VM assembly.

error

The types of errors that might occur throughout execution.

sync

Items related to stepping forward VM execution by synchronous operations.

Structs

Access

All necessary solution access required to check an individual predicate.

ExecFuture

A future that when polled attempts to make progress on VM execution.

GasLimit

Gas limits.

LazyCache

Lazily cache expensive to compute values.

Memory

Memory for temporary storage of words.

OpAsync

The set of operations that are performed asynchronously.

Repeat

A stack of repeat counters.

Stack

The VM’s Stack, i.e. a Vec of Words updated during each step of execution.

Vm

The operation execution state of the VM.

Enums

Op

All operations available to the Essential VM execution.

OpSync

The set of operations that are performed synchronously.

ProgramControlFlow

Update the program to a new position or halt it.

Traits

OpAccess

Types that provide access to operations.

OpGasCost

A mapping from an operation to its gas cost.

StateRead

Read-only access to state required by the VM.

Functions

mut_keys

A helper for collecting all mutable keys that are proposed for mutation for the predicate at the given index.

mut_keys_set

Get the contract of mutable keys for this predicate.

mut_keys_slices

Get the mutable keys as slices

Type Aliases

BytecodeMapped

Shorthand for the BytecodeMapped type representing a mapping to/from Ops.

BytecodeMappedLazy

Shorthand for the BytecodeMappedLazy type for mapping Ops.

BytecodeMappedSlice

Shorthand for the BytecodeMappedSlice type for mapping Ops.

Gas

Unit used to measure gas.