Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
- Loading branch information
1 parent
4ca6262
commit e04318e
Showing
4 changed files
with
96 additions
and
1 deletion.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,80 @@ | ||
//! Validates the MIR to ensure that invariants are upheld. | ||
|
||
use super::{MirPass, MirSource}; | ||
use rustc_middle::mir::visit::Visitor; | ||
use rustc_middle::{ | ||
mir::{Body, Location, Operand, Rvalue, Statement, StatementKind}, | ||
ty::{ParamEnv, TyCtxt}, | ||
}; | ||
use rustc_span::{def_id::DefId, Span, DUMMY_SP}; | ||
|
||
pub struct Validator { | ||
/// Describes at which point in the pipeline this validation is happening. | ||
pub when: String, | ||
} | ||
|
||
impl<'tcx> MirPass<'tcx> for Validator { | ||
fn run_pass(&self, tcx: TyCtxt<'tcx>, source: MirSource<'tcx>, body: &mut Body<'tcx>) { | ||
let def_id = source.def_id(); | ||
let param_env = tcx.param_env(def_id); | ||
TypeChecker { when: &self.when, def_id, body, tcx, param_env }.visit_body(body); | ||
} | ||
} | ||
|
||
struct TypeChecker<'a, 'tcx> { | ||
when: &'a str, | ||
def_id: DefId, | ||
body: &'a Body<'tcx>, | ||
tcx: TyCtxt<'tcx>, | ||
param_env: ParamEnv<'tcx>, | ||
} | ||
|
||
impl<'a, 'tcx> TypeChecker<'a, 'tcx> { | ||
fn fail(&self, span: Span, msg: impl AsRef<str>) { | ||
// We use `delay_span_bug` as we might see broken MIR when other errors have already | ||
// occurred. | ||
self.tcx.sess.diagnostic().delay_span_bug( | ||
span, | ||
&format!("broken MIR in {:?} ({}): {}", self.def_id, self.when, msg.as_ref()), | ||
); | ||
} | ||
} | ||
|
||
impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> { | ||
fn visit_operand(&mut self, operand: &Operand<'tcx>, location: Location) { | ||
// `Operand::Copy` is only supposed to be used with `Copy` types. | ||
if let Operand::Copy(place) = operand { | ||
let ty = place.ty(&self.body.local_decls, self.tcx).ty; | ||
|
||
if !ty.is_copy_modulo_regions(self.tcx, self.param_env, DUMMY_SP) { | ||
self.fail( | ||
DUMMY_SP, | ||
format!("`Operand::Copy` with non-`Copy` type {} at {:?}", ty, location), | ||
); | ||
} | ||
} | ||
|
||
self.super_operand(operand, location); | ||
} | ||
|
||
fn visit_statement(&mut self, statement: &Statement<'tcx>, location: Location) { | ||
// The sides of an assignment must not alias. Currently this just checks whether the places | ||
// are identical. | ||
if let StatementKind::Assign(box (dest, rvalue)) = &statement.kind { | ||
match rvalue { | ||
Rvalue::Use(Operand::Copy(src) | Operand::Move(src)) => { | ||
if dest == src { | ||
self.fail( | ||
DUMMY_SP, | ||
format!( | ||
"encountered `Assign` statement with overlapping memory at {:?}", | ||
location | ||
), | ||
); | ||
} | ||
} | ||
_ => {} | ||
} | ||
} | ||
} | ||
} |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters