Struct lief::macho::commands::FunctionVariants

pub struct FunctionVariants<'a> { /* private fields */ }

Class representing the LC_FUNCTION_VARIANTS load command.

Introduced publicly in dyld-1284.13 (April 2025), this command supports function multiversioning, the ability to associate multiple implementations of the same function, each optimized for a specific platform, architecture, or runtime context.

At runtime, the system dispatches the most appropriate variant based on hardware capabilities or execution environment.

For example:

FUNCTION_VARIANT_TABLE(my_function,
  { (void*)my_function$Rosetta,  "rosetta" }, // Rosetta translation
  { (void*)my_function$Haswell,  "haswell" }, // Haswell-optimized
  { (void*)my_function$Base,     "default" }  // Default fallback
);

Implementations

impl FunctionVariants<'_>

pub fn data_offset(&self) -> u32

Offset in the __LINKEDIT segment where the payload is located

pub fn data_size(&self) -> u32

Size of the payload

pub fn content(&self) -> &[u8]

Raw payload as a slice of bytes

pub fn runtime_table(&self) -> RuntimeTables<'_>

Iterator over the different RuntimeTable entries located in the content of this __LINKEDIT command

Trait Implementations

impl Command for FunctionVariants<'_>

fn size(&self) -> u32

Size of the command (should be greater than sizeof(load_command))

fn offset(&self) -> u64

Offset of the command within the Load Command Table

fn command_type(&self) -> LoadCommandTypes

The command’s type

fn data(&self) -> &[u8]

The raw command as a slice of bytes

impl Debug for FunctionVariants<'_>

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

Formats the value using the given formatter.