Merge pull request #985 from alexcrichton/differeng-gc

Restructure internals of `wasm-gc`
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Nick Fitzgerald 2018-10-29 10:45:53 +01:00 committed by GitHub
commit 1ec68009e8
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@ -57,37 +57,41 @@ fn run(config: &mut Config, module: &mut Module) {
cx.blacklist.insert("__heap_base");
cx.blacklist.insert("__data_end");
// always treat memory as a root
cx.add_memory(0);
// All exports are a root
if let Some(section) = module.export_section() {
for (i, entry) in section.entries().iter().enumerate() {
if cx.blacklist.contains(entry.field()) {
continue
}
cx.add_export_entry(entry, i as u32);
}
}
if let Some(section) = module.import_section() {
for (i, entry) in section.entries().iter().enumerate() {
debug!("import {:?}", entry);
if let External::Memory(_) = *entry.external() {
cx.add_import_entry(entry, i as u32);
}
}
}
// Pessimistically assume all passive data and table segments are
// required
if let Some(section) = module.data_section() {
for entry in section.entries() {
cx.add_data_segment(entry);
}
}
if let Some(tables) = module.table_section() {
for i in 0..tables.entries().len() as u32 {
cx.add_table(i);
if entry.passive() {
cx.add_data_segment(entry);
}
}
}
if let Some(elements) = module.elements_section() {
for seg in elements.entries() {
cx.add_element_segment(seg);
if seg.passive() {
cx.add_element_segment(seg);
}
}
}
// The start function is also a root
if let Some(i) = module.start_section() {
cx.add_function(i);
}
cx.analysis
};
@ -132,7 +136,6 @@ fn run(config: &mut Config, module: &mut Module) {
#[derive(Default)]
struct Analysis {
codes: BitSet,
tables: BitSet,
memories: BitSet,
globals: BitSet,
@ -140,67 +143,56 @@ struct Analysis {
imports: BitSet,
exports: BitSet,
functions: BitSet,
all_globals: BitSet,
}
enum Memories<'a> {
Exported(&'a MemorySection),
Imported(&'a MemoryType),
}
impl<'a> Memories<'a> {
fn has_entry(&self, idx: usize) -> bool {
match *self {
Memories::Exported(memory_section) => idx < memory_section.entries().len(),
Memories::Imported(_) => idx == 0,
}
}
imported_functions: u32,
imported_globals: u32,
imported_memories: u32,
imported_tables: u32,
}
struct LiveContext<'a> {
blacklist: HashSet<&'static str>,
function_section: Option<&'a FunctionSection>,
type_section: Option<&'a TypeSection>,
data_section: Option<&'a DataSection>,
element_section: Option<&'a ElementSection>,
code_section: Option<&'a CodeSection>,
table_section: Option<&'a TableSection>,
memories: Option<Memories<'a>>,
global_section: Option<&'a GlobalSection>,
import_section: Option<&'a ImportSection>,
imported_functions: u32,
imported_globals: u32,
analysis: Analysis,
}
impl<'a> LiveContext<'a> {
fn new(module: &'a Module) -> LiveContext<'a> {
let memories = module.memory_section().map(Memories::Exported).or_else(|| {
if let Some(import_section) = module.import_section() {
for entry in import_section.entries() {
if let External::Memory(ref memory_type) = *entry.external() {
return Some(Memories::Imported(memory_type));
}
let (mut tables, mut memories, mut globals, mut functions) = (0, 0, 0, 0);
if let Some(imports) = module.import_section() {
for entry in imports.entries() {
match entry.external() {
External::Memory(_) => memories += 1,
External::Table(_) => tables += 1,
External::Function(_) => functions += 1,
External::Global(_) => globals += 1,
}
}
None
});
}
LiveContext {
blacklist: HashSet::new(),
function_section: module.function_section(),
type_section: module.type_section(),
data_section: module.data_section(),
element_section: module.elements_section(),
code_section: module.code_section(),
table_section: module.table_section(),
memories: memories,
global_section: module.global_section(),
import_section: module.import_section(),
imported_functions: module.import_section()
.map(|s| s.functions())
.unwrap_or(0) as u32,
imported_globals: module.import_section()
.map(|s| s.globals())
.unwrap_or(0) as u32,
analysis: Analysis::default(),
analysis: Analysis {
imported_functions: functions,
imported_globals: globals,
imported_tables: tables,
imported_memories: memories,
..Analysis::default()
},
}
}
@ -208,10 +200,10 @@ impl<'a> LiveContext<'a> {
if !self.analysis.functions.insert(idx) {
return
}
debug!("adding function: {}", idx);
if idx < self.imported_functions {
if idx < self.analysis.imported_functions {
let imports = self.import_section.unwrap();
debug!("adding import: {}", idx);
let (i, import) = imports.entries()
.iter()
.enumerate()
@ -225,57 +217,48 @@ impl<'a> LiveContext<'a> {
.next()
.expect("expected an imported function with this index");
let i = i as u32;
self.analysis.imports.insert(i);
return self.add_import_entry(import, i);
}
let idx = idx - self.imported_functions;
if !self.analysis.codes.insert(idx) {
return
}
debug!("adding function: {}", idx);
let idx = idx - self.analysis.imported_functions;
let functions = self.function_section.expect("no functions section");
self.add_type(functions.entries()[idx as usize].type_ref());
let codes = self.code_section.expect("no codes section");
self.add_func_body(&codes.bodies()[idx as usize]);
}
fn add_table(&mut self, mut idx: u32) {
if let Some(imports) = self.import_section {
let imported_tables = imports.entries()
fn add_table(&mut self, idx: u32) {
if !self.analysis.tables.insert(idx) {
return
}
debug!("adding table: {}", idx);
// Add all element segments that initialize this table
if let Some(elements) = self.element_section {
for entry in elements.entries().iter().filter(|d| !d.passive()) {
if entry.index() == idx {
self.add_element_segment(entry);
}
}
}
if idx < self.analysis.imported_tables {
let imports = self.import_section.unwrap();
let (i, import) = imports.entries()
.iter()
.filter(|i| {
.enumerate()
.filter(|&(_, i)| {
match *i.external() {
External::Table(_) => true,
_ => false,
}
})
.count();
let imported_tables = imported_tables as u32;
if idx < imported_tables {
debug!("adding table import: {}", idx);
let (i, import) = imports.entries()
.iter()
.enumerate()
.filter(|&(_, i)| {
match *i.external() {
External::Table(_) => true,
_ => false,
}
})
.skip(idx as usize)
.next()
.expect("expected an imported table with this index");
let i = i as u32;
self.analysis.imports.insert(i);
return self.add_import_entry(import, i);
}
idx -= imported_tables;
}
if !self.analysis.tables.insert(idx) {
return
.skip(idx as usize)
.next()
.expect("expected an imported table with this index");
let i = i as u32;
return self.add_import_entry(import, i);
}
let idx = idx - self.analysis.imported_tables;
let tables = self.table_section.expect("no table section");
let table = &tables.entries()[idx as usize];
drop(table);
@ -285,18 +268,47 @@ impl<'a> LiveContext<'a> {
if !self.analysis.memories.insert(idx) {
return
}
let memories = self.memories.as_ref().expect("no memory section or imported memory");
assert!(memories.has_entry(idx as usize));
debug!("adding memory: {}", idx);
// Add all data segments that initialize this memory
if let Some(data) = self.data_section {
for entry in data.entries().iter().filter(|d| !d.passive()) {
if entry.index() == idx {
self.add_data_segment(entry);
}
}
}
// ... and add the import if it's an imported memory ..
if idx < self.analysis.imported_memories {
let imports = self.import_section.unwrap();
let (i, import) = imports.entries()
.iter()
.enumerate()
.filter(|&(_, i)| {
match *i.external() {
External::Memory(_) => true,
_ => false,
}
})
.skip(idx as usize)
.next()
.expect("expected an imported memory with this index");
let i = i as u32;
return self.add_import_entry(import, i);
}
// ... and if it's not imported that's it!
}
fn add_global(&mut self, idx: u32) {
if !self.analysis.all_globals.insert(idx) {
if !self.analysis.globals.insert(idx) {
return
}
debug!("adding global: {}", idx);
if idx < self.imported_globals {
if idx < self.analysis.imported_globals {
let imports = self.import_section.unwrap();
debug!("adding global import: {}", idx);
let (i, import) = imports.entries()
.iter()
.enumerate()
@ -310,14 +322,10 @@ impl<'a> LiveContext<'a> {
.next()
.expect("expected an imported global with this index");
let i = i as u32;
self.analysis.imports.insert(i);
return self.add_import_entry(import, i);
}
let idx = idx - self.imported_globals;
if !self.analysis.globals.insert(idx) {
return
}
let idx = idx - self.analysis.imported_globals;
let globals = self.global_section.expect("no global section");
let global = &globals.entries()[idx as usize];
self.add_global_type(global.global_type());
@ -380,7 +388,10 @@ impl<'a> LiveContext<'a> {
Instruction::Loop(ref b) |
Instruction::If(ref b) => self.add_block_type(b),
Instruction::Call(f) => self.add_function(f),
Instruction::CallIndirect(t, _) => self.add_type(t),
Instruction::CallIndirect(t, _) => {
self.add_type(t);
self.add_table(0);
}
Instruction::GetGlobal(i) |
Instruction::SetGlobal(i) => self.add_global(i),
_ => {}
@ -395,10 +406,9 @@ impl<'a> LiveContext<'a> {
}
fn add_export_entry(&mut self, entry: &ExportEntry, idx: u32) {
if self.blacklist.contains(entry.field()) {
if !self.analysis.exports.insert(idx) {
return
}
self.analysis.exports.insert(idx);
match *entry.internal() {
Internal::Function(i) => self.add_function(i),
Internal::Table(i) => self.add_table(i),
@ -408,14 +418,15 @@ impl<'a> LiveContext<'a> {
}
fn add_import_entry(&mut self, entry: &ImportEntry, idx: u32) {
if !self.analysis.imports.insert(idx) {
return
}
debug!("adding import: {}", idx);
match *entry.external() {
External::Function(i) => self.add_type(i),
External::Table(_) => {},
External::Memory(_) => {
self.add_memory(0);
self.analysis.imports.insert(idx);
},
External::Global(_) => {},
External::Table(_) => {}
External::Memory(_) => {}
External::Global(g) => self.add_value_type(&g.content_type()),
}
}
@ -490,7 +501,7 @@ impl<'a> RemapContext<'a> {
}
if let Some(s) = m.function_section() {
for i in 0..(s.entries().len() as u32) {
if analysis.codes.contains(&i) {
if analysis.functions.contains(&(i + analysis.imported_functions)) {
functions.push(nfunctions);
nfunctions += 1;
} else {
@ -501,7 +512,7 @@ impl<'a> RemapContext<'a> {
}
if let Some(s) = m.global_section() {
for i in 0..(s.entries().len() as u32) {
if analysis.globals.contains(&i) {
if analysis.globals.contains(&(i + analysis.imported_globals)) {
globals.push(nglobals);
nglobals += 1;
} else {
@ -512,7 +523,7 @@ impl<'a> RemapContext<'a> {
}
if let Some(s) = m.table_section() {
for i in 0..(s.entries().len() as u32) {
if analysis.tables.contains(&i) {
if analysis.tables.contains(&(i + analysis.imported_tables)) {
tables.push(ntables);
ntables += 1;
} else {
@ -523,7 +534,7 @@ impl<'a> RemapContext<'a> {
}
if let Some(s) = m.memory_section() {
for i in 0..(s.entries().len() as u32) {
if analysis.memories.contains(&i) {
if analysis.memories.contains(&(i + analysis.imported_memories)) {
memories.push(nmemories);
nmemories += 1;
} else {
@ -544,9 +555,9 @@ impl<'a> RemapContext<'a> {
}
}
fn retain<T>(&self, set: &BitSet, list: &mut Vec<T>, name: &str) {
fn retain<T>(&self, set: &BitSet, list: &mut Vec<T>, name: &str, offset: u32) {
for i in (0..list.len()).rev().map(|x| x as u32) {
if !set.contains(&i) {
if !set.contains(&(i + offset)) {
debug!("removing {} {}", name, i);
list.remove(i as usize);
}
@ -554,7 +565,7 @@ impl<'a> RemapContext<'a> {
}
fn remap_type_section(&self, s: &mut TypeSection) -> bool {
self.retain(&self.analysis.types, s.types_mut(), "type");
self.retain(&self.analysis.types, s.types_mut(), "type", 0);
for t in s.types_mut() {
self.remap_type(t);
}
@ -577,11 +588,17 @@ impl<'a> RemapContext<'a> {
}
fn remap_value_type(&self, t: &mut ValueType) {
drop(t);
match t {
ValueType::I32 => {}
ValueType::I64 => {}
ValueType::F32 => {}
ValueType::F64 => {}
ValueType::V128 => {}
}
}
fn remap_import_section(&self, s: &mut ImportSection) -> bool {
self.retain(&self.analysis.imports, s.entries_mut(), "import");
self.retain(&self.analysis.imports, s.entries_mut(), "import", 0);
for i in s.entries_mut() {
self.remap_import_entry(i);
}
@ -599,7 +616,12 @@ impl<'a> RemapContext<'a> {
}
fn remap_function_section(&self, s: &mut FunctionSection) -> bool {
self.retain(&self.analysis.codes, s.entries_mut(), "function");
self.retain(
&self.analysis.functions,
s.entries_mut(),
"function",
self.analysis.imported_functions,
);
for f in s.entries_mut() {
self.remap_func(f);
}
@ -611,7 +633,12 @@ impl<'a> RemapContext<'a> {
}
fn remap_table_section(&self, s: &mut TableSection) -> bool {
self.retain(&self.analysis.tables, s.entries_mut(), "table");
self.retain(
&self.analysis.tables,
s.entries_mut(),
"table",
self.analysis.imported_tables,
);
for t in s.entries_mut() {
drop(t); // TODO
}
@ -619,7 +646,12 @@ impl<'a> RemapContext<'a> {
}
fn remap_memory_section(&self, s: &mut MemorySection) -> bool {
self.retain(&self.analysis.memories, s.entries_mut(), "memory");
self.retain(
&self.analysis.memories,
s.entries_mut(),
"memory",
self.analysis.imported_memories,
);
for m in s.entries_mut() {
drop(m); // TODO
}
@ -627,7 +659,12 @@ impl<'a> RemapContext<'a> {
}
fn remap_global_section(&self, s: &mut GlobalSection) -> bool {
self.retain(&self.analysis.globals, s.entries_mut(), "global");
self.retain(
&self.analysis.globals,
s.entries_mut(),
"global",
self.analysis.imported_globals,
);
for g in s.entries_mut() {
self.remap_global_entry(g);
}
@ -650,7 +687,7 @@ impl<'a> RemapContext<'a> {
}
fn remap_export_section(&self, s: &mut ExportSection) -> bool {
self.retain(&self.analysis.exports, s.entries_mut(), "export");
self.retain(&self.analysis.exports, s.entries_mut(), "export", 0);
for s in s.entries_mut() {
self.remap_export_entry(s);
}
@ -686,7 +723,12 @@ impl<'a> RemapContext<'a> {
}
fn remap_code_section(&self, s: &mut CodeSection) -> bool {
self.retain(&self.analysis.codes, s.bodies_mut(), "code");
self.retain(
&self.analysis.functions,
s.bodies_mut(),
"code",
self.analysis.imported_functions,
);
for s in s.bodies_mut() {
self.remap_func_body(s);
}