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use syntax::abi::{Abi};
use syntax::ast;
use syntax_pos::Span;
use rustc::ty::{self, TyCtxt};
use rustc::mir::{self, Mir};
use rustc_data_structures::indexed_vec::Idx;
use super::super::gather_moves::{MovePathIndex, LookupResult};
use super::BitDenotation;
use super::DataflowResults;
use super::super::gather_moves::HasMoveData;
pub fn sanity_check_via_rustc_peek<'a, 'tcx, O>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
mir: &Mir<'tcx>,
id: ast::NodeId,
_attributes: &[ast::Attribute],
results: &DataflowResults<O>)
where O: BitDenotation<Idx=MovePathIndex> + HasMoveData<'tcx>
{
debug!("sanity_check_via_rustc_peek id: {:?}", id);
for bb in mir.basic_blocks().indices() {
each_block(tcx, mir, results, bb);
}
}
fn each_block<'a, 'tcx, O>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
mir: &Mir<'tcx>,
results: &DataflowResults<O>,
bb: mir::BasicBlock) where
O: BitDenotation<Idx=MovePathIndex> + HasMoveData<'tcx>
{
let move_data = results.0.operator.move_data();
let mir::BasicBlockData { ref statements, ref terminator, is_cleanup: _ } = mir[bb];
let (args, span) = match is_rustc_peek(tcx, terminator) {
Some(args_and_span) => args_and_span,
None => return,
};
assert!(args.len() == 1);
let peek_arg_lval = match args[0] {
mir::Operand::Consume(ref lval @ mir::Lvalue::Local(_)) => Some(lval),
_ => None,
};
let peek_arg_lval = match peek_arg_lval {
Some(arg) => arg,
None => {
tcx.sess.diagnostic().span_err(
span, "dataflow::sanity_check cannot feed a non-temp to rustc_peek.");
return;
}
};
let mut entry = results.0.sets.on_entry_set_for(bb.index()).to_owned();
let mut gen = results.0.sets.gen_set_for(bb.index()).to_owned();
let mut kill = results.0.sets.kill_set_for(bb.index()).to_owned();
let mut sets = super::BlockSets { on_entry: &mut entry,
gen_set: &mut gen,
kill_set: &mut kill };
for (j, stmt) in statements.iter().enumerate() {
debug!("rustc_peek: ({:?},{}) {:?}", bb, j, stmt);
let (lvalue, rvalue) = match stmt.kind {
mir::StatementKind::Assign(ref lvalue, ref rvalue) => {
(lvalue, rvalue)
}
mir::StatementKind::StorageLive(_) |
mir::StatementKind::StorageDead(_) |
mir::StatementKind::InlineAsm { .. } |
mir::StatementKind::Nop => continue,
mir::StatementKind::SetDiscriminant{ .. } =>
span_bug!(stmt.source_info.span,
"sanity_check should run before Deaggregator inserts SetDiscriminant"),
};
if lvalue == peek_arg_lval {
if let mir::Rvalue::Ref(_, mir::BorrowKind::Shared, ref peeking_at_lval) = *rvalue {
match move_data.rev_lookup.find(peeking_at_lval) {
LookupResult::Exact(peek_mpi) => {
let bit_state = sets.on_entry.contains(&peek_mpi);
debug!("rustc_peek({:?} = &{:?}) bit_state: {}",
lvalue, peeking_at_lval, bit_state);
if !bit_state {
tcx.sess.span_err(span, "rustc_peek: bit not set");
}
}
LookupResult::Parent(..) => {
tcx.sess.span_err(span, "rustc_peek: argument untracked");
}
}
return;
} else {
let msg = "rustc_peek: argument expression \
must be immediate borrow of form `&expr`";
tcx.sess.span_err(span, msg);
}
}
let lhs_mpi = move_data.rev_lookup.find(lvalue);
debug!("rustc_peek: computing effect on lvalue: {:?} ({:?}) in stmt: {:?}",
lvalue, lhs_mpi, stmt);
for e in sets.gen_set.words_mut() { *e = 0; }
for e in sets.kill_set.words_mut() { *e = 0; }
results.0.operator.statement_effect(&mut sets, bb, j);
sets.on_entry.union(sets.gen_set);
sets.on_entry.subtract(sets.kill_set);
}
tcx.sess.span_err(span, &format!("rustc_peek: MIR did not match \
anticipated pattern; note that \
rustc_peek expects input of \
form `&expr`"));
}
fn is_rustc_peek<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
terminator: &'a Option<mir::Terminator<'tcx>>)
-> Option<(&'a [mir::Operand<'tcx>], Span)> {
if let Some(mir::Terminator { ref kind, source_info, .. }) = *terminator {
if let mir::TerminatorKind::Call { func: ref oper, ref args, .. } = *kind
{
if let mir::Operand::Constant(ref func) = *oper
{
if let ty::TyFnDef(def_id, _, sig) = func.ty.sty
{
let abi = sig.abi();
let name = tcx.item_name(def_id);
if abi == Abi::RustIntrinsic || abi == Abi::PlatformIntrinsic {
if name == "rustc_peek" {
return Some((args, source_info.span));
}
}
}
}
}
}
return None;
}