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use bitflags::bitflags;
use crate::category::CategoryPairHandle;
use crate::global_lib_table::LibraryHandle;
use crate::profile::StringHandle;
/// A part of the information about a single stack frame.
#[derive(Debug, Clone, PartialOrd, Ord, PartialEq, Eq)]
pub enum Frame {
/// A code address taken from the instruction pointer.
///
/// This code address will be resolved to a library-relative address using
/// the library mappings on the process which were specified using
/// [`Profile::add_lib_mapping`](crate::Profile::add_lib_mapping).
InstructionPointer(u64),
/// A code address taken from a return address
///
/// This code address will be resolved to a library-relative address using
/// the library mappings on the process which were specified using
/// [`Profile::add_lib_mapping`](crate::Profile::add_lib_mapping).
ReturnAddress(u64),
/// A code address taken from a return address, but adjusted so that it
/// points into the previous instruction. Usually this is "return address
/// minus one byte", but some unwinders subtract 2 or 4 bytes if they know
/// more about the architecture-dependent instruction size.
///
/// When you call a function with a call instruction, the return address
/// is set up in such a way that, once the called function returns, the CPU
/// continues executing after the call instruction. That means that the return
/// address points to the instruction *after* the call instruction. But for
/// stack unwinding, you're interested in **the call instruction itself**.
/// The call instruction and the instruction after often have very different
/// symbol information (different line numbers, or even different inline stacks).
///
/// This code address will be resolved to a library-relative address using
/// the library mappings on the process which were specified using
/// [`Profile::add_lib_mapping`](crate::Profile::add_lib_mapping).
AdjustedReturnAddress(u64),
/// A relative address taken from the instruction pointer which
/// has already been resolved to a `LibraryHandle`.
RelativeAddressFromInstructionPointer(LibraryHandle, u32),
/// A relative address taken from a return address which
/// has already been resolved to a `LibraryHandle`.
RelativeAddressFromReturnAddress(LibraryHandle, u32),
/// A relative address taken from an adjusted return address which
/// has already been resolved to a `LibraryHandle`.
RelativeAddressFromAdjustedReturnAddress(LibraryHandle, u32),
/// A string, containing an index returned by
/// [`Profile::intern_string`](crate::Profile::intern_string).
Label(StringHandle),
}
/// All the information about a single stack frame.
#[derive(Debug, Clone, PartialOrd, Ord, PartialEq, Eq)]
pub struct FrameInfo {
/// The absolute address or label of this frame.
pub frame: Frame,
/// The category pair of this frame.
pub category_pair: CategoryPairHandle,
/// The flags of this frame. Use `FrameFlags::empty()` if unsure.
pub flags: FrameFlags,
}
bitflags! {
/// Flags for a stack frame.
#[derive(PartialEq, Eq, PartialOrd, Ord, Hash, Debug, Clone, Copy)]
pub struct FrameFlags: u32 {
/// Set on frames which are JavaScript functions.
const IS_JS = 0b00000001;
/// Set on frames which are not strictly JavaScript functions but which
/// should be included in the JS-only call tree, such as DOM API calls.
const IS_RELEVANT_FOR_JS = 0b00000010;
}
}