Struct walrus::ModuleConfig

pub struct ModuleConfig { /* fields omitted */ }

Configuration for a Module which currently affects parsing.

Methods

impl ModuleConfig

pub fn new() -> ModuleConfig

Creates a fresh new configuration with default settings.

pub fn generate_dwarf(&mut self, generate: bool) -> &mut ModuleConfig

Sets a flag to whether DWARF debug sections are generated for this module.

By default this flag is false. Note that any emitted DWARF is currently wildly incorrect and buggy, and is also larger than the wasm itself!

pub fn generate_name_section(&mut self, generate: bool) -> &mut ModuleConfig

Sets a flag to whether the custom "name" section is generated for this module.

The "name" section contains symbol names for the module, functions, and locals. When enabled, stack traces will use these names, instead of wasm-function[123].

By default this flag is true.

pub fn generate_synthetic_names_for_anonymous_items(
    &mut self,
    generate: bool
) -> &mut ModuleConfig

Sets a flag to whether synthetic debugging names are generated for anonymous locals/functions/etc when parsing and running passes for this module.

By default this flag is false, and it will generate quite a few names if enabled!

pub fn strict_validate(&mut self, strict: bool) -> &mut ModuleConfig

Indicates whether the module, after parsing, performs strict validation of the wasm module to adhere with the current version of the wasm specification.

This can be expensive for some modules and strictly isn't required to create a Module from a wasm file. This includes checks such as "atomic instructions require a shared memory".

By default this flag is true

pub fn generate_producers_section(
    &mut self,
    generate: bool
) -> &mut ModuleConfig

Indicates whether the module will have the "producers" custom section which preserves the original producers and also includes walrus.

This is generally used for telemetry in browsers, but for otherwise tiny wasm binaries can add some size to the binary.

By default this flag is true

pub fn only_stable_features(&mut self, only: bool) -> &mut ModuleConfig

Indicates whether this module is allowed to use only stable WebAssembly features or not.

This is currently used to disable some validity checks required by the WebAssembly specification. It's not religiously adhered to throughout the codebase, even if set to true some unstable features may still be allowed.

By default this flag is false

pub fn on_parse<F>(&mut self, f: F) -> &mut ModuleConfig where
    F: Fn(&mut Module, &IndicesToIds) -> Result<()> + Send + Sync + 'static, 

Provide a function that is invoked after successfully parsing a module, and gets access to data structures that only exist at parse time, such as the map from indices in the original Wasm to the new walrus IDs.

This is a good place to parse custom sections that reference things by index.

This will never be invoked for modules that are created from scratch, and are not parsed from an existing Wasm binary.

Note that only one on_parse function may be registered and subsequent registrations will override the old ones.

Note that cloning a ModuleConfig will result in a config that does not have an on_parse function, even if the original did.

pub fn on_instr_loc<F>(&mut self, f: F) -> &mut ModuleConfig where
    F: Fn(&usize) -> InstrLocId + Send + Sync + 'static, 

Provide a function that is invoked on source location ID step.

Note that cloning a ModuleConfig will result in a config that does not have an on_instr_loc function, even if the original did.

pub fn preserve_code_transform(&mut self, preserve: bool) -> &mut ModuleConfig

Sets a flag to whether code transform is preverved during parsing.

By default this flag is false.

pub fn parse(&self, wasm: &[u8]) -> Result<Module>

Parses an in-memory WebAssembly file into a Module using this configuration.

pub fn parse_file<P>(&self, path: P) -> Result<Module> where
    P: AsRef<Path>, 

Parses a WebAssembly file into a Module using this configuration.

Trait Implementations

impl Clone for ModuleConfig

fn clone(&self) -> ModuleConfig

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Default for ModuleConfig

fn default() -> ModuleConfig

Returns the "default value" for a type.

impl Debug for ModuleConfig

fn fmt(&self, f: &mut Formatter) -> Result

Formats the value using the given formatter.