pub struct CodeSection { /* private fields */ }
Expand description

An encoder for the code section.

Code sections are only supported for modules.

Example

use wasm_encoder::{
    CodeSection, Function, FunctionSection, Instruction, Module,
    TypeSection, ValType
};

let mut types = TypeSection::new();
types.function(vec![], vec![ValType::I32]);

let mut functions = FunctionSection::new();
let type_index = 0;
functions.function(type_index);

let locals = vec![];
let mut func = Function::new(locals);
func.instruction(&Instruction::I32Const(42));
let mut code = CodeSection::new();
code.function(&func);

let mut module = Module::new();
module
    .section(&types)
    .section(&functions)
    .section(&code);

let wasm_bytes = module.finish();

Implementations

Create a new code section encoder.

The number of functions in the section.

The number of bytes already added to this section.

This number doesn’t include the vector length that precedes the code entries, since it has a variable size that isn’t known until all functions are added.

Determines if the section is empty.

Write a function body into this code section.

Add a raw byte slice into this code section as a function body.

The length prefix of the function body will be automatically prepended, and should not be included in the raw byte slice.

Example

You can use the raw method to copy an already-encoded function body into a new code section encoder:

//                  id, size, # entries, entry
let code_section = [10, 6,    1,         4, 0, 65, 0, 11];

// Parse the code section.
let mut reader = wasmparser::CodeSectionReader::new(&code_section, 0).unwrap();
let body = reader.read().unwrap();
let body_range = body.range();

// Add the body to a new code section encoder by copying bytes rather
// than re-parsing and re-encoding it.
let mut encoder = wasm_encoder::CodeSection::new();
encoder.raw(&code_section[body_range.start..body_range.end]);

Trait Implementations

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

Formats the value using the given formatter. Read more

Returns the “default value” for a type. Read more

Encode the type into the given byte sink.

Gets the section identifier for this section.

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

The resulting type after obtaining ownership.

Creates owned data from borrowed data, usually by cloning. Read more

🔬 This is a nightly-only experimental API. (toowned_clone_into)

Uses borrowed data to replace owned data, usually by cloning. Read more

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.