Struct fxprof_processed_profile::LibMappings

pub struct LibMappings<T> { /* private fields */ }

Keeps track of mapped libraries in an address space. Stores a value for each mapping, and allows efficient lookup of that value based on an address.

A “library” here is a loose term; it could be a normal shared library, or the main binary, but it could also be a synthetic library for JIT code. For normal libraries, there’s usually just one mapping per library. For JIT code, you could have many small mappings, one per JIT function, all pointing to the synthetic JIT “library”.

Implementations

impl<T> LibMappings<T>

pub fn new() -> Self

Creates a new empty instance.

pub fn add_mapping( &mut self, start_avma: u64, end_avma: u64, relative_address_at_start: u32, value: T )

Add a mapping to this address space. Any existing mappings which overlap with the new mapping are removed.

start_avma and end_avma describe the address range that this mapping occupies.

AVMA = “actual virtual memory address”

relative_address_at_start is the “relative address” which corresponds to start_avma, in the library that is mapped in this mapping. This is zero if start_avm is the base address of the library.

A relative address is a u32 value which is relative to the library base address. So you will usually set relative_address_at_start to start_avma - base_avma.

For ELF binaries, the base address is the AVMA of the first segment, i.e. the start_avma of the mapping created by the first ELF LOAD command.

For mach-O binaries, the base address is the vmaddr of the __TEXT segment.

For Windows binaries, the base address is the image load address.

pub fn remove_mapping(&mut self, start_avma: u64) -> Option<(u32, T)>

Remove a mapping which starts at the given address. If found, this returns the relative_address_at_start and the associated value of the mapping.

pub fn clear(&mut self)

Clear all mappings.

pub fn lookup(&self, avma: u64) -> Option<&T>

Look up the mapping which covers the given address and return the stored value.

pub fn convert_address(&self, avma: u64) -> Option<(u32, &T)>

Converts an absolute address (AVMA, actual virtual memory address) into a relative address and the mapping’s associated value.

Trait Implementations

impl<T: Clone> Clone for LibMappings<T>

fn clone(&self) -> LibMappings<T>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<T: Debug> Debug for LibMappings<T>

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

Formats the value using the given formatter.

impl<T> Default for LibMappings<T>

fn default() -> Self

Returns the “default value” for a type.