bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

Auto merge of #110822 - scottmcm:lower-offset-to-mir, r=compiler-errors

Browse source 
Lower `intrinsics::offset` to `mir::BinOp::Offset`

They're [semantically the same](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/mir/enum.Rvalue.html#variant.BinaryOp), so this means the backends don't need to handle the intrinsic and means fewer MIR basic blocks in pointer arithmetic code.
This commit is contained in:
bors 2023-04-26 15:52:33 +00:00
commit 9c044d77a3
7 changed files with 66 additions and 20 deletions
Download patch file Download diff file Expand all files Collapse all files

17
compiler/rustc_mir_transform/src/lower_intrinsics.rs
View file

@ -192,6 +192,23 @@ impl<'tcx> MirPass<'tcx> for LowerIntrinsics {
terminator.kind = TerminatorKind::Goto { target };
}
}
sym::offset => {
let target = target.unwrap();
let Ok([ptr, delta]) = <[_; 2]>::try_from(std::mem::take(args)) else {
span_bug!(
terminator.source_info.span,
"Wrong number of arguments for offset intrinsic",
);
};
block.statements.push(Statement {
source_info: terminator.source_info,
kind: StatementKind::Assign(Box::new((
*destination,
Rvalue::BinaryOp(BinOp::Offset, Box::new((ptr, delta))),
))),
});
terminator.kind = TerminatorKind::Goto { target };
}
sym::option_payload_ptr => {
if let (Some(target), Some(arg)) = (*target, args[0].place()) {
let ty::RawPtr(ty::TypeAndMut { ty: dest_ty, .. }) =