Introduce indexvec macro.

Author: cjgillot

compiler/rustc_index/src/lib.rs

@@ -50,3 +50,13 @@ macro_rules! static_assert_size {
         const _: (usize, usize) = ($size, ::std::mem::size_of::<$ty>());
     };
 }
+
+#[macro_export]
+macro_rules! indexvec {
+    ($expr:expr; $n:expr) => {
+        IndexVec::from_raw(vec![$expr; $n])
+    };
+    ($($expr:expr),* $(,)?) => {
+        IndexVec::from_raw(vec![$($expr),*])
+    };
+}

compiler/rustc_mir_transform/src/coroutine.rs

@@ -67,7 +67,7 @@ use rustc_hir as hir;
 use rustc_hir::lang_items::LangItem;
 use rustc_hir::{CoroutineDesugaring, CoroutineKind};
 use rustc_index::bit_set::{BitMatrix, DenseBitSet, GrowableBitSet};
-use rustc_index::{Idx, IndexVec};
+use rustc_index::{Idx, IndexVec, indexvec};
 use rustc_middle::mir::visit::{MutVisitor, MutatingUseContext, PlaceContext, Visitor};
 use rustc_middle::mir::*;
 use rustc_middle::ty::util::Discr;
@@ -289,7 +289,7 @@ impl<'tcx> TransformVisitor<'tcx> {
                 let poll_def_id = self.tcx.require_lang_item(LangItem::Poll, source_info.span);
                 let args = self.tcx.mk_args(&[self.old_ret_ty.into()]);
                 let (variant_idx, operands) = if is_return {
-                    (ZERO, IndexVec::from_raw(vec![val])) // Poll::Ready(val)
+                    (ZERO, indexvec![val]) // Poll::Ready(val)
                 } else {
                     (ONE, IndexVec::new()) // Poll::Pending
                 };
@@ -301,7 +301,7 @@ impl<'tcx> TransformVisitor<'tcx> {
                 let (variant_idx, operands) = if is_return {
                     (ZERO, IndexVec::new()) // None
                 } else {
-                    (ONE, IndexVec::from_raw(vec![val])) // Some(val)
+                    (ONE, indexvec![val]) // Some(val)
                 };
                 make_aggregate_adt(option_def_id, variant_idx, args, operands)
             }
@@ -337,12 +337,7 @@ impl<'tcx> TransformVisitor<'tcx> {
                 } else {
                     ZERO // CoroutineState::Yielded(val)
                 };
-                make_aggregate_adt(
-                    coroutine_state_def_id,
-                    variant_idx,
-                    args,
-                    IndexVec::from_raw(vec![val]),
-                )
+                make_aggregate_adt(coroutine_state_def_id, variant_idx, args, indexvec![val])
             }
         };
 
@@ -1122,7 +1117,7 @@ fn return_poll_ready_assign<'tcx>(tcx: TyCtxt<'tcx>, source_info: SourceInfo) ->
     }));
     let ready_val = Rvalue::Aggregate(
         Box::new(AggregateKind::Adt(poll_def_id, VariantIdx::from_usize(0), args, None, None)),
-        IndexVec::from_raw(vec![val]),
+        indexvec![val],
     );
     Statement::new(source_info, StatementKind::Assign(Box::new((Place::return_place(), ready_val))))
 }

compiler/rustc_mir_transform/src/elaborate_box_derefs.rs

@@ -6,7 +6,7 @@
 //! contents, we do not need this any more on runtime MIR.
 
 use rustc_abi::{FieldIdx, VariantIdx};
-use rustc_index::IndexVec;
+use rustc_index::{IndexVec, indexvec};
 use rustc_middle::mir::visit::MutVisitor;
 use rustc_middle::mir::*;
 use rustc_middle::span_bug;
@@ -127,7 +127,7 @@ impl<'a, 'tcx> MutVisitor<'tcx> for ElaborateBoxDerefVisitor<'a, 'tcx> {
                 nonnull.into(),
                 Rvalue::Aggregate(
                     adt_kind(self.nonnull_def, args),
-                    IndexVec::from_raw(vec![Operand::Move(constptr.into())]),
+                    indexvec![Operand::Move(constptr.into())],
                 ),
             );
 
@@ -139,15 +139,15 @@ impl<'a, 'tcx> MutVisitor<'tcx> for ElaborateBoxDerefVisitor<'a, 'tcx> {
                 unique.into(),
                 Rvalue::Aggregate(
                     adt_kind(self.unique_def, args),
-                    IndexVec::from_raw(vec![Operand::Move(nonnull.into()), zst(phantomdata_ty)]),
+                    indexvec![Operand::Move(nonnull.into()), zst(phantomdata_ty)],
                 ),
             );
 
             let global_alloc_ty =
                 box_adt.non_enum_variant().fields[FieldIdx::ONE].ty(tcx, box_args);
             *rvalue = Rvalue::Aggregate(
                 adt_kind(*box_adt, box_args),
-                IndexVec::from_raw(vec![Operand::Move(unique.into()), zst(global_alloc_ty)]),
+                indexvec![Operand::Move(unique.into()), zst(global_alloc_ty)],
             );
         }
     }