bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

Codegen fewer instructions in mem::replace

Browse source
This commit is contained in:
Scott McMurray 2023-04-29 23:32:40 -07:00
parent ca3f742ff6
commit 5292d48b85
13 changed files with 154 additions and 78 deletions
Download patch file Download diff file Expand all files Collapse all files

23
compiler/rustc_mir_transform/src/lower_intrinsics.rs
View file

@ -179,6 +179,29 @@ impl<'tcx> MirPass<'tcx> for LowerIntrinsics {
}
}
}
sym::write_via_move => {
let target = target.unwrap();
let Ok([ptr, val]) = <[_; 2]>::try_from(std::mem::take(args)) else {
span_bug!(
terminator.source_info.span,
"Wrong number of arguments for write_via_move intrinsic",
);
};
let derefed_place =
if let Some(place) = ptr.place() && let Some(local) = place.as_local() {
tcx.mk_place_deref(local.into())
} else {
span_bug!(terminator.source_info.span, "Only passing a local is supported");
};
block.statements.push(Statement {
source_info: terminator.source_info,
kind: StatementKind::Assign(Box::new((
derefed_place,
Rvalue::Use(val),
))),
});
terminator.kind = TerminatorKind::Goto { target };
}
sym::discriminant_value => {
if let (Some(target), Some(arg)) = (*target, args[0].place()) {
let arg = tcx.mk_place_deref(arg);