Struct CasmBuilder

pub struct CasmBuilder { /* private fields */ }

Builder to more easily write casm code.

Allows CASM building without specifically thinking about ap changes and the sizes of opcodes. Wrong usages of it would panic instead of returning a result, as this builder assumes we are in a post validation of parameters stage.

Implementations

impl CasmBuilder

pub fn build<const BRANCH_COUNT: usize>( self, branch_names: [&str; BRANCH_COUNT], ) -> CasmBuildResult<BRANCH_COUNT>

Finalizes the builder, with the requested labels as the returning branches. “Fallthrough” is a special case for the fallthrough case.

pub fn curr_ap_change(&self) -> usize

Returns the current ap change of the builder. Useful for manual ap change handling.

pub fn add_var(&mut self, value: CellExpression) -> Var

Adds a variable pointing to value.

pub fn alloc_var(&mut self, local_var: bool) -> Var

Allocates a new variable in memory, either local (FP-based) or temp (AP-based).

pub fn duplicate_var(&mut self, var: Var) -> Var

Returns an additional variable pointing to the same value.

pub fn add_hint<const INPUTS_COUNT: usize, const OUTPUTS_COUNT: usize, THint: Into<Hint>, F: FnOnce([ResOperand; INPUTS_COUNT], [CellRef; OUTPUTS_COUNT]) -> THint>( &mut self, f: F, inputs: [Var; INPUTS_COUNT], outputs: [Var; OUTPUTS_COUNT], )

Adds a hint, generated from inputs which are cell refs or immediates and outputs which must be cell refs.

pub fn assert_vars_eq(&mut self, dst: Var, res: Var)

Adds an assertion that dst = res. dst must be a cell reference.

pub fn buffer_write_and_inc(&mut self, buffer: Var, value: Var)

Writes and increments a buffer. Useful for RangeCheck and similar buffers. buffer must be a cell reference, or a cell reference with a small added constant. value must be a cell reference.

pub fn maybe_add_tempvar(&mut self, var: Var) -> Var

Writes var as a new tempvar and returns it as a variable, unless its value is already deref (which includes trivial calculations as well) so it instead returns a variable pointing to that location.

pub fn get_ref_and_inc(&mut self, buffer: Var) -> Var

Increments a buffer and allocates and returns variable pointing to its previous value.

pub fn add_ap(&mut self, size: usize)

Increases AP by size.

pub fn increase_ap_change(&mut self, amount: usize)

Increases the AP change by size, without adding an instruction.

pub fn bin_op(&mut self, op: CellOperator, lhs: Var, rhs: Var) -> Var

Returns a variable that is the op of lhs and rhs. lhs must be a cell reference and rhs must be deref or immediate.

pub fn double_deref(&mut self, var: Var, offset: i16) -> Var

Returns a variable that is [[var] + offset]. var must be a cell reference, or a cell ref plus a small constant.

pub fn jump(&mut self, label: String)

Add a statement to jump to label.

pub fn jump_nz(&mut self, condition: Var, label: String)

Add a statement to jump to label if condition != 0. condition must be a cell reference.

pub fn label(&mut self, name: String)

Adds a label here named name.

pub fn future_label(&mut self, name: String, offset: usize)

Adds a label name in distance offset from the current point. Useful for calling code outside of the builder’s context.

pub fn rescope<const VAR_COUNT: usize>(&mut self, vars: [(Var, Var); VAR_COUNT])

Rescoping the values, while ignoring all vars not stated in vars and giving the vars on the left side the values of the vars on the right side.

pub fn call(&mut self, label: String)

Adds a call command to ‘label’. All AP based variables are passed to the called function state and dropped from the calling function state.

pub fn ret(&mut self)

A return statement in the code.

pub fn steps(&self) -> usize

The number of steps at the last added statement.

pub fn reset_steps(&mut self)

Resets the steps counter.

pub fn fail(&mut self)

Create an assert that would always fail.

pub fn mark_unreachable(&mut self)

Marks the current state as unreachable. Useful for removing bookkeeping after unsatisfiable conditions.

pub fn get_value(&self, var: Var, adjust_ap: bool) -> CellExpression

Returns vars value, with fixed ap if adjust_ap is true.

Trait Implementations

impl Default for CasmBuilder

fn default() -> Self

Returns the “default value” for a type.