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//! Define the `instantiate` function, which takes a byte array containing an
//! encoded wasm module and returns a live wasm instance. Also, define
//! `CompiledModule` to allow compiling and instantiating to be done as separate
//! steps.
use crate::code_memory::CodeMemory;
use crate::debug::create_gdbjit_image;
use crate::ProfilingAgent;
use anyhow::{anyhow, bail, Context, Error, Result};
use object::write::{Object, StandardSegment, WritableBuffer};
use object::{File, Object as _, ObjectSection, SectionKind};
use serde::{Deserialize, Serialize};
use std::convert::TryFrom;
use std::ops::Range;
use std::str;
use std::sync::Arc;
use thiserror::Error;
use wasmtime_environ::{
CompileError, DefinedFuncIndex, FuncIndex, FunctionInfo, Module, ModuleTranslation, PrimaryMap,
SignatureIndex, StackMapInformation, Trampoline, Tunables, ELF_WASMTIME_ADDRMAP,
ELF_WASMTIME_TRAPS,
};
use wasmtime_runtime::{
CompiledModuleId, CompiledModuleIdAllocator, GdbJitImageRegistration, InstantiationError,
MmapVec, VMFunctionBody, VMTrampoline,
};
/// This is the name of the section in the final ELF image which contains
/// concatenated data segments from the original wasm module.
///
/// This section is simply a list of bytes and ranges into this section are
/// stored within a `Module` for each data segment. Memory initialization and
/// passive segment management all index data directly located in this section.
///
/// Note that this implementation does not afford any method of leveraging the
/// `data.drop` instruction to actually release the data back to the OS. The
/// data section is simply always present in the ELF image. If we wanted to
/// release the data it's probably best to figure out what the best
/// implementation is for it at the time given a particular set of constraints.
const ELF_WASM_DATA: &'static str = ".rodata.wasm";
/// This is the name of the section in the final ELF image which contains a
/// `bincode`-encoded `CompiledModuleInfo`.
///
/// This section is optionally decoded in `CompiledModule::from_artifacts`
/// depending on whether or not a `CompiledModuleInfo` is already available. In
/// cases like `Module::new` where compilation directly leads into consumption,
/// it's available. In cases like `Module::deserialize` this section must be
/// decoded to get all the relevant information.
const ELF_WASMTIME_INFO: &'static str = ".wasmtime.info";
/// This is the name of the section in the final ELF image which contains a
/// concatenated list of all function names.
///
/// This section is optionally included in the final artifact depending on
/// whether the wasm module has any name data at all (or in the future if we add
/// an option to not preserve name data). This section is a concatenated list of
/// strings where `CompiledModuleInfo::func_names` stores offsets/lengths into
/// this section.
///
/// Note that the goal of this section is to avoid having to decode names at
/// module-load time if we can. Names are typically only used for debugging or
/// things like backtraces so there's no need to eagerly load all of them. By
/// storing the data in a separate section the hope is that the data, which is
/// sometimes quite large (3MB seen for spidermonkey-compiled-to-wasm), can be
/// paged in lazily from an mmap and is never paged in if we never reference it.
const ELF_NAME_DATA: &'static str = ".name.wasm";
/// An error condition while setting up a wasm instance, be it validation,
/// compilation, or instantiation.
#[derive(Error, Debug)]
pub enum SetupError {
/// The module did not pass validation.
#[error("Validation error: {0}")]
Validate(String),
/// A wasm translation error occurred.
#[error("WebAssembly failed to compile")]
Compile(#[from] CompileError),
/// Some runtime resource was unavailable or insufficient, or the start function
/// trapped.
#[error("Instantiation failed during setup")]
Instantiate(#[from] InstantiationError),
/// Debug information generation error occurred.
#[error("Debug information error")]
DebugInfo(#[from] anyhow::Error),
}
/// Secondary in-memory results of compilation.
///
/// This opaque structure can be optionally passed back to
/// `CompiledModule::from_artifacts` to avoid decoding extra information there.
#[derive(Serialize, Deserialize)]
pub struct CompiledModuleInfo {
/// Type information about the compiled WebAssembly module.
module: Module,
/// Metadata about each compiled function.
funcs: PrimaryMap<DefinedFuncIndex, FunctionInfo>,
/// Sorted list, by function index, of names we have for this module.
func_names: Vec<FunctionName>,
/// The trampolines compiled into the text section and their start/length
/// relative to the start of the text section.
trampolines: Vec<Trampoline>,
/// General compilation metadata.
meta: Metadata,
}
#[derive(Serialize, Deserialize)]
struct FunctionName {
idx: FuncIndex,
offset: u32,
len: u32,
}
#[derive(Serialize, Deserialize)]
struct Metadata {
/// Whether or not native debug information is available in `obj`
native_debug_info_present: bool,
/// Whether or not the original wasm module contained debug information that
/// we skipped and did not parse.
has_unparsed_debuginfo: bool,
/// Offset in the original wasm file to the code section.
code_section_offset: u64,
/// Whether or not custom wasm-specific dwarf sections were inserted into
/// the ELF image.
///
/// Note that even if this flag is `true` sections may be missing if they
/// weren't found in the original wasm module itself.
has_wasm_debuginfo: bool,
}
/// Finishes compilation of the `translation` specified, producing the final
/// compilation artifact and auxiliary information.
///
/// This function will consume the final results of compiling a wasm module
/// and finish the ELF image in-progress as part of `obj` by appending any
/// compiler-agnostic sections.
///
/// The auxiliary `CompiledModuleInfo` structure returned here has also been
/// serialized into the object returned, but if the caller will quickly
/// turn-around and invoke `CompiledModule::from_artifacts` after this then the
/// information can be passed to that method to avoid extra deserialization.
/// This is done to avoid a serialize-then-deserialize for API calls like
/// `Module::new` where the compiled module is immediately going to be used.
///
/// The `MmapVec` returned here contains the compiled image and resides in
/// mmap'd memory for easily switching permissions to executable afterwards.
pub fn finish_compile(
translation: ModuleTranslation<'_>,
mut obj: Object,
funcs: PrimaryMap<DefinedFuncIndex, FunctionInfo>,
trampolines: Vec<Trampoline>,
tunables: &Tunables,
) -> Result<(MmapVec, CompiledModuleInfo)> {
let ModuleTranslation {
mut module,
debuginfo,
has_unparsed_debuginfo,
data,
data_align,
passive_data,
..
} = translation;
// Place all data from the wasm module into a section which will the
// source of the data later at runtime.
let data_id = obj.add_section(
obj.segment_name(StandardSegment::Data).to_vec(),
ELF_WASM_DATA.as_bytes().to_vec(),
SectionKind::ReadOnlyData,
);
let mut total_data_len = 0;
for (i, data) in data.iter().enumerate() {
// The first data segment has its alignment specified as the alignment
// for the entire section, but everything afterwards is adjacent so it
// has alignment of 1.
let align = if i == 0 { data_align.unwrap_or(1) } else { 1 };
obj.append_section_data(data_id, data, align);
total_data_len += data.len();
}
for data in passive_data.iter() {
obj.append_section_data(data_id, data, 1);
}
// If any names are present in the module then the `ELF_NAME_DATA` section
// is create and appended.
let mut func_names = Vec::new();
if debuginfo.name_section.func_names.len() > 0 {
let name_id = obj.add_section(
obj.segment_name(StandardSegment::Data).to_vec(),
ELF_NAME_DATA.as_bytes().to_vec(),
SectionKind::ReadOnlyData,
);
let mut sorted_names = debuginfo.name_section.func_names.iter().collect::<Vec<_>>();
sorted_names.sort_by_key(|(idx, _name)| *idx);
for (idx, name) in sorted_names {
let offset = obj.append_section_data(name_id, name.as_bytes(), 1);
let offset = match u32::try_from(offset) {
Ok(offset) => offset,
Err(_) => bail!("name section too large (> 4gb)"),
};
let len = u32::try_from(name.len()).unwrap();
func_names.push(FunctionName {
idx: *idx,
offset,
len,
});
}
}
// Update passive data offsets since they're all located after the other
// data in the module.
for (_, range) in module.passive_data_map.iter_mut() {
range.start = range.start.checked_add(total_data_len as u32).unwrap();
range.end = range.end.checked_add(total_data_len as u32).unwrap();
}
// Insert the wasm raw wasm-based debuginfo into the output, if
// requested. Note that this is distinct from the native debuginfo
// possibly generated by the native compiler, hence these sections
// getting wasm-specific names.
if tunables.parse_wasm_debuginfo {
push_debug(&mut obj, &debuginfo.dwarf.debug_abbrev);
push_debug(&mut obj, &debuginfo.dwarf.debug_addr);
push_debug(&mut obj, &debuginfo.dwarf.debug_aranges);
push_debug(&mut obj, &debuginfo.dwarf.debug_info);
push_debug(&mut obj, &debuginfo.dwarf.debug_line);
push_debug(&mut obj, &debuginfo.dwarf.debug_line_str);
push_debug(&mut obj, &debuginfo.dwarf.debug_str);
push_debug(&mut obj, &debuginfo.dwarf.debug_str_offsets);
push_debug(&mut obj, &debuginfo.debug_ranges);
push_debug(&mut obj, &debuginfo.debug_rnglists);
}
// Encode a `CompiledModuleInfo` structure into the `ELF_WASMTIME_INFO`
// section of this image. This is not necessary when the returned module
// is never serialized to disk, which is also why we return a copy of
// the `CompiledModuleInfo` structure to the caller in case they don't
// want to deserialize this value immediately afterwards from the
// section. Otherwise, though, this is necessary to reify a `Module` on
// the other side from disk-serialized artifacts in
// `Module::deserialize` (a Wasmtime API).
let info_id = obj.add_section(
obj.segment_name(StandardSegment::Data).to_vec(),
ELF_WASMTIME_INFO.as_bytes().to_vec(),
SectionKind::ReadOnlyData,
);
let mut bytes = Vec::new();
let info = CompiledModuleInfo {
module,
funcs,
trampolines,
func_names,
meta: Metadata {
native_debug_info_present: tunables.generate_native_debuginfo,
has_unparsed_debuginfo,
code_section_offset: debuginfo.wasm_file.code_section_offset,
has_wasm_debuginfo: tunables.parse_wasm_debuginfo,
},
};
bincode::serialize_into(&mut bytes, &info)?;
obj.append_section_data(info_id, &bytes, 1);
return Ok((mmap_vec_from_obj(obj)?, info));
fn push_debug<'a, T>(obj: &mut Object, section: &T)
where
T: gimli::Section<gimli::EndianSlice<'a, gimli::LittleEndian>>,
{
let data = section.reader().slice();
if data.is_empty() {
return;
}
let section_id = obj.add_section(
obj.segment_name(StandardSegment::Debug).to_vec(),
wasm_section_name(T::id()).as_bytes().to_vec(),
SectionKind::Debug,
);
obj.append_section_data(section_id, data, 1);
}
}
/// Creates a new `MmapVec` from serializing the specified `obj`.
///
/// The returned `MmapVec` will contain the serialized version of `obj` and
/// is sized appropriately to the exact size of the object serialized.
pub fn mmap_vec_from_obj(obj: Object) -> Result<MmapVec> {
let mut result = ObjectMmap::default();
return match obj.emit(&mut result) {
Ok(()) => {
assert!(result.mmap.is_some(), "no reserve");
let mmap = result.mmap.expect("reserve not called");
assert_eq!(mmap.len(), result.len);
Ok(mmap)
}
Err(e) => match result.err.take() {
Some(original) => Err(original.context(e)),
None => Err(e.into()),
},
};
/// Helper struct to implement the `WritableBuffer` trait from the `object`
/// crate.
///
/// This enables writing an object directly into an mmap'd memory so it's
/// immediately usable for execution after compilation. This implementation
/// relies on a call to `reserve` happening once up front with all the needed
/// data, and the mmap internally does not attempt to grow afterwards.
#[derive(Default)]
struct ObjectMmap {
mmap: Option<MmapVec>,
len: usize,
err: Option<Error>,
}
impl WritableBuffer for ObjectMmap {
fn len(&self) -> usize {
self.len
}
fn reserve(&mut self, additional: usize) -> Result<(), ()> {
assert!(self.mmap.is_none(), "cannot reserve twice");
self.mmap = match MmapVec::with_capacity(additional) {
Ok(mmap) => Some(mmap),
Err(e) => {
self.err = Some(e);
return Err(());
}
};
Ok(())
}
fn resize(&mut self, new_len: usize) {
// Resizing always appends 0 bytes and since new mmaps start out as 0
// bytes we don't actually need to do anything as part of this other
// than update our own length.
if new_len <= self.len {
return;
}
self.len = new_len;
}
fn write_bytes(&mut self, val: &[u8]) {
let mmap = self.mmap.as_mut().expect("write before reserve");
mmap[self.len..][..val.len()].copy_from_slice(val);
self.len += val.len();
}
}
}
/// A compiled wasm module, ready to be instantiated.
pub struct CompiledModule {
wasm_data: Range<usize>,
address_map_data: Range<usize>,
trap_data: Range<usize>,
module: Arc<Module>,
funcs: PrimaryMap<DefinedFuncIndex, FunctionInfo>,
trampolines: Vec<Trampoline>,
meta: Metadata,
code: Range<usize>,
code_memory: CodeMemory,
dbg_jit_registration: Option<GdbJitImageRegistration>,
/// A unique ID used to register this module with the engine.
unique_id: CompiledModuleId,
func_names: Vec<FunctionName>,
func_name_data: Range<usize>,
}
impl CompiledModule {
/// Creates `CompiledModule` directly from a precompiled artifact.
///
/// The `mmap` argument is expecte to be the result of a previous call to
/// `finish_compile` above. This is an ELF image, at this time, which
/// contains all necessary information to create a `CompiledModule` from a
/// compilation.
///
/// This method also takes `info`, an optionally-provided deserialization of
/// the artifacts' compilation metadata section. If this information is not
/// provided (e.g. it's set to `None`) then the information will be
/// deserialized from the image of the compilation artifacts. Otherwise it
/// will be assumed to be what would otherwise happen if the section were to
/// be deserialized.
///
/// The `profiler` argument here is used to inform JIT profiling runtimes
/// about new code that is loaded.
pub fn from_artifacts(
mmap: MmapVec,
info: Option<CompiledModuleInfo>,
profiler: &dyn ProfilingAgent,
id_allocator: &CompiledModuleIdAllocator,
) -> Result<Self> {
// Transfer ownership of `obj` to a `CodeMemory` object which will
// manage permissions, such as the executable bit. Once it's located
// there we also publish it for being able to execute. Note that this
// step will also resolve pending relocations in the compiled image.
let mut code_memory = CodeMemory::new(mmap);
let code = code_memory
.publish()
.context("failed to publish code memory")?;
let section = |name: &str| {
code.obj
.section_by_name(name)
.and_then(|s| s.data().ok())
.ok_or_else(|| anyhow!("missing section `{}` in compilation artifacts", name))
};
// Acquire the `CompiledModuleInfo`, either because it was passed in or
// by deserializing it from the compiliation image.
let info = match info {
Some(info) => info,
None => bincode::deserialize(section(ELF_WASMTIME_INFO)?)
.context("failed to deserialize wasmtime module info")?,
};
let func_name_data = match code
.obj
.section_by_name(ELF_NAME_DATA)
.and_then(|s| s.data().ok())
{
Some(data) => subslice_range(data, code.mmap),
None => 0..0,
};
let mut ret = Self {
module: Arc::new(info.module),
funcs: info.funcs,
trampolines: info.trampolines,
wasm_data: subslice_range(section(ELF_WASM_DATA)?, code.mmap),
address_map_data: code
.obj
.section_by_name(ELF_WASMTIME_ADDRMAP)
.and_then(|s| s.data().ok())
.map(|slice| subslice_range(slice, code.mmap))
.unwrap_or(0..0),
trap_data: subslice_range(section(ELF_WASMTIME_TRAPS)?, code.mmap),
code: subslice_range(code.text, code.mmap),
dbg_jit_registration: None,
code_memory,
meta: info.meta,
unique_id: id_allocator.alloc(),
func_names: info.func_names,
func_name_data,
};
ret.register_debug_and_profiling(profiler)?;
Ok(ret)
}
fn register_debug_and_profiling(&mut self, profiler: &dyn ProfilingAgent) -> Result<()> {
// Register GDB JIT images; initialize profiler and load the wasm module.
if self.meta.native_debug_info_present {
let code = self.code();
let bytes = create_gdbjit_image(self.mmap().to_vec(), (code.as_ptr(), code.len()))
.map_err(SetupError::DebugInfo)?;
profiler.module_load(self, Some(&bytes));
let reg = GdbJitImageRegistration::register(bytes);
self.dbg_jit_registration = Some(reg);
} else {
profiler.module_load(self, None);
}
Ok(())
}
/// Get this module's unique ID. It is unique with respect to a
/// single allocator (which is ordinarily held on a Wasm engine).
pub fn unique_id(&self) -> CompiledModuleId {
self.unique_id
}
/// Returns the underlying memory which contains the compiled module's
/// image.
pub fn mmap(&self) -> &MmapVec {
self.code_memory.mmap()
}
/// Returns the concatenated list of all data associated with this wasm
/// module.
///
/// This is used for initialization of memories and all data ranges stored
/// in a `Module` are relative to the slice returned here.
pub fn wasm_data(&self) -> &[u8] {
&self.mmap()[self.wasm_data.clone()]
}
/// Returns the encoded address map section used to pass to
/// `wasmtime_environ::lookup_file_pos`.
pub fn address_map_data(&self) -> &[u8] {
&self.mmap()[self.address_map_data.clone()]
}
/// Returns the encoded trap information for this compiled image.
///
/// For more information see `wasmtime_environ::trap_encoding`.
pub fn trap_data(&self) -> &[u8] {
&self.mmap()[self.trap_data.clone()]
}
/// Returns the text section of the ELF image for this compiled module.
///
/// This memory should have the read/execute permissions.
pub fn code(&self) -> &[u8] {
&self.mmap()[self.code.clone()]
}
/// Return a reference-counting pointer to a module.
pub fn module(&self) -> &Arc<Module> {
&self.module
}
/// Looks up the `name` section name for the function index `idx`, if one
/// was specified in the original wasm module.
pub fn func_name(&self, idx: FuncIndex) -> Option<&str> {
// Find entry for `idx`, if present.
let i = self.func_names.binary_search_by_key(&idx, |n| n.idx).ok()?;
let name = &self.func_names[i];
// Here we `unwrap` the `from_utf8` but this can theoretically be a
// `from_utf8_unchecked` if we really wanted since this section is
// guaranteed to only have valid utf-8 data. Until it's a problem it's
// probably best to double-check this though.
let data = &self.mmap()[self.func_name_data.clone()];
Some(str::from_utf8(&data[name.offset as usize..][..name.len as usize]).unwrap())
}
/// Return a reference to a mutable module (if possible).
pub fn module_mut(&mut self) -> Option<&mut Module> {
Arc::get_mut(&mut self.module)
}
/// Returns the map of all finished JIT functions compiled for this module
#[inline]
pub fn finished_functions(
&self,
) -> impl ExactSizeIterator<Item = (DefinedFuncIndex, *const [VMFunctionBody])> + '_ {
let code = self.code();
self.funcs.iter().map(move |(i, info)| {
let func = &code[info.start as usize..][..info.length as usize];
(
i,
std::ptr::slice_from_raw_parts(func.as_ptr().cast::<VMFunctionBody>(), func.len()),
)
})
}
/// Returns the per-signature trampolines for this module.
pub fn trampolines(&self) -> impl Iterator<Item = (SignatureIndex, VMTrampoline, usize)> + '_ {
let code = self.code();
self.trampolines.iter().map(move |info| {
(
info.signature,
unsafe {
let ptr = &code[info.start as usize];
std::mem::transmute::<*const u8, VMTrampoline>(ptr)
},
info.length as usize,
)
})
}
/// Returns the stack map information for all functions defined in this
/// module.
///
/// The iterator returned iterates over the span of the compiled function in
/// memory with the stack maps associated with those bytes.
pub fn stack_maps(
&self,
) -> impl Iterator<Item = (*const [VMFunctionBody], &[StackMapInformation])> {
self.finished_functions()
.map(|(_, f)| f)
.zip(self.funcs.values().map(|f| f.stack_maps.as_slice()))
}
/// Lookups a defined function by a program counter value.
///
/// Returns the defined function index and the relative address of
/// `text_offset` within the function itself.
pub fn func_by_text_offset(&self, text_offset: usize) -> Option<(DefinedFuncIndex, u32)> {
let text_offset = text_offset as u64;
let index = match self
.funcs
.binary_search_values_by_key(&text_offset, |info| {
debug_assert!(info.length > 0);
// Return the inclusive "end" of the function
info.start + u64::from(info.length) - 1
}) {
Ok(k) => {
// Exact match, pc is at the end of this function
k
}
Err(k) => {
// Not an exact match, k is where `pc` would be "inserted"
// Since we key based on the end, function `k` might contain `pc`,
// so we'll validate on the range check below
k
}
};
let body = self.funcs.get(index)?;
let start = body.start;
let end = body.start + u64::from(body.length);
if text_offset < start || end < text_offset {
return None;
}
Some((index, (text_offset - body.start) as u32))
}
/// Gets the function information for a given function index.
pub fn func_info(&self, index: DefinedFuncIndex) -> &FunctionInfo {
self.funcs
.get(index)
.expect("defined function should be present")
}
/// Creates a new symbolication context which can be used to further
/// symbolicate stack traces.
///
/// Basically this makes a thing which parses debuginfo and can tell you
/// what filename and line number a wasm pc comes from.
pub fn symbolize_context(&self) -> Result<Option<SymbolizeContext<'_>>> {
use gimli::EndianSlice;
if !self.meta.has_wasm_debuginfo {
return Ok(None);
}
let obj = File::parse(&self.mmap()[..])
.context("failed to parse internal ELF file representation")?;
let dwarf = gimli::Dwarf::load(|id| -> Result<_> {
let data = obj
.section_by_name(wasm_section_name(id))
.and_then(|s| s.data().ok())
.unwrap_or(&[]);
Ok(EndianSlice::new(data, gimli::LittleEndian))
})?;
let cx = addr2line::Context::from_dwarf(dwarf)
.context("failed to create addr2line dwarf mapping context")?;
Ok(Some(SymbolizeContext {
inner: cx,
code_section_offset: self.meta.code_section_offset,
}))
}
/// Returns whether the original wasm module had unparsed debug information
/// based on the tunables configuration.
pub fn has_unparsed_debuginfo(&self) -> bool {
self.meta.has_unparsed_debuginfo
}
/// Indicates whether this module came with n address map such that lookups
/// via `wasmtime_environ::lookup_file_pos` will succeed.
///
/// If this function returns `false` then `lookup_file_pos` will always
/// return `None`.
pub fn has_address_map(&self) -> bool {
!self.address_map_data().is_empty()
}
/// Returns the bounds, in host memory, of where this module's compiled
/// image resides.
pub fn image_range(&self) -> Range<usize> {
let base = self.mmap().as_ptr() as usize;
let len = self.mmap().len();
base..base + len
}
}
type Addr2LineContext<'a> = addr2line::Context<gimli::EndianSlice<'a, gimli::LittleEndian>>;
/// A context which contains dwarf debug information to translate program
/// counters back to filenames and line numbers.
pub struct SymbolizeContext<'a> {
inner: Addr2LineContext<'a>,
code_section_offset: u64,
}
impl<'a> SymbolizeContext<'a> {
/// Returns access to the [`addr2line::Context`] which can be used to query
/// frame information with.
pub fn addr2line(&self) -> &Addr2LineContext<'a> {
&self.inner
}
/// Returns the offset of the code section in the original wasm file, used
/// to calculate lookup values into the DWARF.
pub fn code_section_offset(&self) -> u64 {
self.code_section_offset
}
}
/// Returns the range of `inner` within `outer`, such that `outer[range]` is the
/// same as `inner`.
///
/// This method requires that `inner` is a sub-slice of `outer`, and if that
/// isn't true then this method will panic.
pub fn subslice_range(inner: &[u8], outer: &[u8]) -> Range<usize> {
if inner.len() == 0 {
return 0..0;
}
assert!(outer.as_ptr() <= inner.as_ptr());
assert!((&inner[inner.len() - 1] as *const _) <= (&outer[outer.len() - 1] as *const _));
let start = inner.as_ptr() as usize - outer.as_ptr() as usize;
start..start + inner.len()
}
/// Returns the Wasmtime-specific section name for dwarf debugging sections.
///
/// These sections, if configured in Wasmtime, will contain the original raw
/// dwarf debugging information found in the wasm file, unmodified. These tables
/// are then consulted later to convert wasm program counters to original wasm
/// source filenames/line numbers with `addr2line`.
fn wasm_section_name(id: gimli::SectionId) -> &'static str {
use gimli::SectionId::*;
match id {
DebugAbbrev => ".debug_abbrev.wasm",
DebugAddr => ".debug_addr.wasm",
DebugAranges => ".debug_aranges.wasm",
DebugFrame => ".debug_frame.wasm",
EhFrame => ".eh_frame.wasm",
EhFrameHdr => ".eh_frame_hdr.wasm",
DebugInfo => ".debug_info.wasm",
DebugLine => ".debug_line.wasm",
DebugLineStr => ".debug_line_str.wasm",
DebugLoc => ".debug_loc.wasm",
DebugLocLists => ".debug_loc_lists.wasm",
DebugMacinfo => ".debug_macinfo.wasm",
DebugMacro => ".debug_macro.wasm",
DebugPubNames => ".debug_pub_names.wasm",
DebugPubTypes => ".debug_pub_types.wasm",
DebugRanges => ".debug_ranges.wasm",
DebugRngLists => ".debug_rng_lists.wasm",
DebugStr => ".debug_str.wasm",
DebugStrOffsets => ".debug_str_offsets.wasm",
DebugTypes => ".debug_types.wasm",
DebugCuIndex => ".debug_cu_index.wasm",
DebugTuIndex => ".debug_tu_index.wasm",
}
}