use references to avoid function calls

compiler/rustc_mir_transform/src/const_prop.rs

@@ -12,8 +12,9 @@
     MutVisitor, MutatingUseContext, NonMutatingUseContext, PlaceContext, Visitor,
 };
 use rustc_middle::mir::{
-    BasicBlock, BinOp, Body, Constant, ConstantKind, Local, LocalKind, Location, Operand, Place,
+    BasicBlock, BinOp, Body, Constant, ConstantKind, Local, LocalDecl, LocalKind, Location,
-    Rvalue, SourceInfo, Statement, StatementKind, Terminator, TerminatorKind, UnOp, RETURN_PLACE,
+    Operand, Place, Rvalue, SourceInfo, Statement, StatementKind, Terminator, TerminatorKind, UnOp,
+    RETURN_PLACE,
 };
 use rustc_middle::ty::layout::{LayoutError, LayoutOf, LayoutOfHelpers, TyAndLayout};
 use rustc_middle::ty::subst::{InternalSubsts, Subst};
@@ -312,6 +313,7 @@ struct ConstPropagator<'mir, 'tcx> {
     ecx: InterpCx<'mir, 'tcx, ConstPropMachine<'mir, 'tcx>>,
     tcx: TyCtxt<'tcx>,
     param_env: ParamEnv<'tcx>,
+    local_decls: &'mir IndexVec<Local, LocalDecl<'tcx>>,
     // Because we have `MutVisitor` we can't obtain the `SourceInfo` from a `Location`. So we store
     // the last known `SourceInfo` here and just keep revisiting it.
     source_info: Option<SourceInfo>,
@@ -393,7 +395,13 @@ fn new(
         )
         .expect("failed to push initial stack frame");
 
-        ConstPropagator { ecx, tcx, param_env, source_info: None }
+        ConstPropagator {
+            ecx,
+            tcx,
+            param_env,
+            local_decls: &dummy_body.local_decls,
+            source_info: None,
+        }
     }
 
     fn get_const(&self, place: Place<'tcx>) -> Option<OpTy<'tcx>> {
@@ -494,7 +502,7 @@ fn check_binary_op(
             let r = r?;
             // We need the type of the LHS. We cannot use `place_layout` as that is the type
             // of the result, which for checked binops is not the same!
-            let left_ty = left.ty(&self.ecx.frame().body.local_decls, self.tcx);
+            let left_ty = left.ty(self.local_decls, self.tcx);
             let left_size = self.ecx.layout_of(left_ty).ok()?.size;
             let right_size = r.layout.size;
             let r_bits = r.to_scalar().ok();
@@ -1116,7 +1124,7 @@ fn visit_terminator(&mut self, terminator: &mut Terminator<'tcx>, location: Loca
                 assert!(
                     self.get_const(local.into()).is_none()
                         || self
-                            .layout_of(self.ecx.frame().body.local_decls[local].ty)
+                            .layout_of(self.local_decls[local].ty)
                             .map_or(true, |layout| layout.is_zst())
                 )
             }

compiler/rustc_mir_transform/src/const_prop_lint.rs

@@ -11,9 +11,9 @@
 use rustc_index::vec::IndexVec;
 use rustc_middle::mir::visit::{MutatingUseContext, NonMutatingUseContext, PlaceContext, Visitor};
 use rustc_middle::mir::{
-    AssertKind, BasicBlock, BinOp, Body, Constant, ConstantKind, Local, LocalKind, Location,
+    AssertKind, BasicBlock, BinOp, Body, Constant, ConstantKind, Local, LocalDecl, LocalKind,
-    Operand, Place, Rvalue, SourceInfo, Statement, StatementKind, Terminator, TerminatorKind, UnOp,
+    Location, Operand, Place, Rvalue, SourceInfo, SourceScope, SourceScopeData, Statement,
-    RETURN_PLACE,
+    StatementKind, Terminator, TerminatorKind, UnOp, RETURN_PLACE,
 };
 use rustc_middle::ty::layout::{LayoutError, LayoutOf, LayoutOfHelpers, TyAndLayout};
 use rustc_middle::ty::subst::{InternalSubsts, Subst};
@@ -308,6 +308,8 @@ struct ConstPropagator<'mir, 'tcx> {
     ecx: InterpCx<'mir, 'tcx, ConstPropMachine<'mir, 'tcx>>,
     tcx: TyCtxt<'tcx>,
     param_env: ParamEnv<'tcx>,
+    source_scopes: &'mir IndexVec<SourceScope, SourceScopeData<'tcx>>,
+    local_decls: &'mir IndexVec<Local, LocalDecl<'tcx>>,
     // Because we have `MutVisitor` we can't obtain the `SourceInfo` from a `Location`. So we store
     // the last known `SourceInfo` here and just keep revisiting it.
     source_info: Option<SourceInfo>,
@@ -389,7 +391,14 @@ fn new(
         )
         .expect("failed to push initial stack frame");
 
-        ConstPropagator { ecx, tcx, param_env, source_info: None }
+        ConstPropagator {
+            ecx,
+            tcx,
+            param_env,
+            source_scopes: &dummy_body.source_scopes,
+            local_decls: &dummy_body.local_decls,
+            source_info: None,
+        }
     }
 
     fn get_const(&self, place: Place<'tcx>) -> Option<OpTy<'tcx>> {
@@ -417,7 +426,7 @@ fn remove_const(ecx: &mut InterpCx<'mir, 'tcx, ConstPropMachine<'mir, 'tcx>>, lo
     }
 
     fn lint_root(&self, source_info: SourceInfo) -> Option<HirId> {
-        source_info.scope.lint_root(&self.ecx.frame().body.source_scopes)
+        source_info.scope.lint_root(self.source_scopes)
     }
 
     fn use_ecx<F, T>(&mut self, f: F) -> Option<T>
@@ -554,7 +563,7 @@ fn check_binary_op(
             let r = r?;
             // We need the type of the LHS. We cannot use `place_layout` as that is the type
             // of the result, which for checked binops is not the same!
-            let left_ty = left.ty(&self.ecx.frame().body.local_decls, self.tcx);
+            let left_ty = left.ty(self.local_decls, self.tcx);
             let left_size = self.ecx.layout_of(left_ty).ok()?.size;
             let right_size = r.layout.size;
             let r_bits = r.to_scalar().ok();
@@ -1008,7 +1017,7 @@ fn fmt(&self, fmt: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
                 assert!(
                     self.get_const(local.into()).is_none()
                         || self
-                            .layout_of(self.ecx.frame().body.local_decls[local].ty)
+                            .layout_of(self.local_decls[local].ty)
                             .map_or(true, |layout| layout.is_zst())
                 )
             }