Bugfix in reachability and local resolution

This commit is contained in:
Chris Fallin 2022-11-30 22:17:28 -08:00
parent 84e16a57da
commit 284be86cd4
No known key found for this signature in database
GPG key ID: 31649E4FE65EB465

View file

@ -301,9 +301,7 @@ fn parse_body<'a>(
let entry = Block::new(0);
builder.body.entry = entry;
builder.locals.seal_block_preds(entry, &mut builder.body);
builder
.locals
.start_block(entry, /* old_reachable = */ false);
builder.locals.start_block(entry);
for (arg_idx, &arg_ty) in module.signature(my_sig).params.iter().enumerate() {
let local_idx = Local::new(arg_idx);
@ -353,6 +351,8 @@ struct LocalTracker {
types: FxHashMap<Local, Type>,
/// The current block.
cur_block: Block,
/// In some block?
in_block: bool,
/// Is the given block sealed?
block_sealed: FxHashSet<Block>,
/// The local-to-value mapping at the start of a block.
@ -369,13 +369,18 @@ impl LocalTracker {
assert!(!was_present);
}
pub fn start_block(&mut self, block: Block, was_reachable: bool) {
self.finish_block(was_reachable);
pub fn start_block(&mut self, block: Block) {
log::trace!("start_block: block {}", block);
assert!(!self.in_block);
self.in_block = true;
self.cur_block = block;
}
pub fn finish_block(&mut self, reachable: bool) {
if !self.in_block {
assert!(!reachable);
return;
}
log::trace!("finish_block: block {}", self.cur_block);
if reachable {
let mapping = std::mem::take(&mut self.in_cur_block);
@ -388,8 +393,10 @@ impl LocalTracker {
old_mapping
);
} else {
self.in_cur_block.clear();
self.block_end.insert(self.cur_block, FxHashMap::default());
}
self.in_block = false;
}
pub fn seal_block_preds(&mut self, block: Block, body: &mut FunctionBody) {
@ -1019,6 +1026,7 @@ impl<'a, 'b> FunctionBodyBuilder<'a, 'b> {
// Get the args off the stack unconditionally.
let args = self.pop_n(frame.br_args().len());
self.emit_branch(frame.br_target(), &args[..]);
self.locals.finish_block(self.reachable);
self.reachable = false;
}
Some(cond) => {
@ -1031,8 +1039,8 @@ impl<'a, 'b> FunctionBodyBuilder<'a, 'b> {
self.emit_cond_branch(cond, frame.br_target(), &args[..], cont, &[]);
self.locals.seal_block_preds(cont, &mut self.body);
self.cur_block = cont;
self.locals
.start_block(cont, /* old_reachable = */ self.reachable);
self.locals.finish_block(self.reachable);
self.locals.start_block(cont);
}
}
}
@ -1141,8 +1149,8 @@ impl<'a, 'b> FunctionBodyBuilder<'a, 'b> {
}
// Set `cur_block` only if currently set (otherwise, unreachable!)
self.cur_block = *out;
self.locals
.start_block(*out, /* old_reachable = */ self.reachable);
self.locals.finish_block(self.reachable);
self.locals.start_block(*out);
self.reachable = was_reachable
|| match &frame {
Some(Frame::Block { out_reachable, .. }) => *out_reachable,
@ -1180,8 +1188,8 @@ impl<'a, 'b> FunctionBodyBuilder<'a, 'b> {
.iter()
.map(|(_ty, value)| *value)
.collect::<Vec<_>>();
self.locals
.start_block(*el, /* old_reachable = */ self.reachable);
self.locals.finish_block(self.reachable);
self.locals.start_block(*el);
self.cur_block = *el;
self.reachable = *head_reachable;
self.emit_branch(*out, &else_result_values[..]);
@ -1191,8 +1199,8 @@ impl<'a, 'b> FunctionBodyBuilder<'a, 'b> {
let else_reachable = self.reachable;
self.reachable = *head_reachable || was_reachable || *merge_reachable;
self.locals.seal_block_preds(*out, &mut self.body);
self.locals
.start_block(*out, /* old_reachable */ else_reachable);
self.locals.finish_block(else_reachable);
self.locals.start_block(*out);
self.push_block_params(results.len());
}
Some(Frame::Else {
@ -1214,8 +1222,8 @@ impl<'a, 'b> FunctionBodyBuilder<'a, 'b> {
self.cur_block = *out;
self.reachable = *merge_reachable || self.reachable;
self.locals.seal_block_preds(*out, &mut self.body);
self.locals
.start_block(*out, /* old_reachable = */ was_reachable);
self.locals.finish_block(was_reachable);
self.locals.start_block(*out);
self.push_block_params(results.len());
}
}
@ -1251,8 +1259,8 @@ impl<'a, 'b> FunctionBodyBuilder<'a, 'b> {
let start_depth = self.op_stack.len();
self.emit_branch(header, &initial_args[..]);
self.cur_block = header;
self.locals
.start_block(header, /* old_reachable = */ self.reachable);
self.locals.finish_block(self.reachable);
self.locals.start_block(header);
self.push_block_params(params.len());
let out = self.body.add_block();
self.add_block_params(out, &results[..]);
@ -1300,8 +1308,8 @@ impl<'a, 'b> FunctionBodyBuilder<'a, 'b> {
self.locals.seal_block_preds(if_true, &mut self.body);
self.locals.seal_block_preds(if_false, &mut self.body);
self.cur_block = if_true;
self.locals
.start_block(if_true, /* old_reachable = */ self.reachable);
self.locals.finish_block(self.reachable);
self.locals.start_block(if_true);
}
wasmparser::Operator::Else => {
@ -1331,8 +1339,8 @@ impl<'a, 'b> FunctionBodyBuilder<'a, 'b> {
merge_reachable: merge_reachable || self.reachable,
});
self.cur_block = el;
self.locals
.start_block(el, /* old_reachable = */ self.reachable);
self.locals.finish_block(self.reachable);
self.locals.start_block(el);
self.reachable = head_reachable;
} else {
bail!(FrontendError::Internal(format!(