do not count non-codegen statement as estimzed cgu element

Author: csmoe

compiler/rustc_codegen_ssa/src/mir/statement.rs

@@ -48,12 +48,6 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
  .codegen_set_discr(&mut bx, variant_index);
  bx
  }
- mir::StatementKind::Deinit(..) => {
- // For now, don't codegen this to anything. In the future it may be worth
- // experimenting with what kind of information we can emit to LLVM without hurting
- // perf here
- bx
- }
  mir::StatementKind::StorageLive(local) => {
  if let LocalRef::Place(cg_place) = self.locals[local] {
  cg_place.storage_live(&mut bx);
@@ -97,6 +91,12 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
  bx.memcpy(dst, align, src, align, bytes, crate::MemFlags::empty());
  bx
  }
+ mir::StatementKind::Deinit(..) => {
+ // For now, don't codegen this to anything. In the future it may be worth
+ // experimenting with what kind of information we can emit to LLVM without hurting
+ // perf here
+ bx
+ }
  mir::StatementKind::FakeRead(..)
  | mir::StatementKind::Retag { .. }
  | mir::StatementKind::AscribeUserType(..)

compiler/rustc_ty_utils/src/ty.rs

@@ -1,6 +1,7 @@
 use rustc_data_structures::fx::FxIndexSet;
 use rustc_hir as hir;
 use rustc_hir::def_id::DefId;
+use rustc_middle::mir::StatementKind;
 use rustc_middle::ty::{self, Binder, Predicate, PredicateKind, ToPredicate, Ty, TyCtxt};
 use rustc_trait_selection::traits;
 
@@ -355,7 +356,25 @@ fn instance_def_size_estimate<'tcx>(
  match instance_def {
  InstanceDef::Item(..) | InstanceDef::DropGlue(..) => {
  let mir = tcx.instance_mir(instance_def);
- mir.basic_blocks.iter().map(|bb| bb.statements.len() + 1).sum()
+ mir.basic_blocks
+ .iter()
+ .map(|bb| {
+ bb.statements
+ .iter()
+ .filter(|s| {
+ // do not count non-codegen statement
+ !matches!(
+ s.kind,
+ StatementKind::Deinit(..)
+ | StatementKind::FakeRead(..)
+ | StatementKind::Retag { .. }
+ | StatementKind::AscribeUserType(..)
+ | StatementKind::Nop
+ )
+ })
+ .count()
+ })
+ .sum()
  }
  // Estimate the size of other compiler-generated shims to be 1.
  _ => 1,