From 7870b296e45a3758ee3f8577303b24128695694f Mon Sep 17 00:00:00 2001
From: bjorn3 <17426603+bjorn3@users.noreply.github.com>
Date: Thu, 9 Feb 2023 11:16:07 +0000
Subject: [PATCH] Remove a couple of duplicate layout_of and monomorphize calls

---
 src/abi/mod.rs       |  8 +++-----
 src/abi/returning.rs |  3 ++-
 src/analyze.rs       | 30 +++++++++++-------------------
 3 files changed, 16 insertions(+), 25 deletions(-)

diff --git a/src/abi/mod.rs b/src/abi/mod.rs
index 3c34585d419..7b9f3e6761a 100644
--- a/src/abi/mod.rs
+++ b/src/abi/mod.rs
@@ -275,10 +275,6 @@ pub(crate) fn codegen_fn_prelude<'tcx>(fx: &mut FunctionCx<'_, '_, 'tcx>, start_
     self::comments::add_locals_header_comment(fx);
 
     for (local, arg_kind, ty) in func_params {
-        let layout = fx.layout_of(ty);
-
-        let is_ssa = ssa_analyzed[local] == crate::analyze::SsaKind::Ssa;
-
         // While this is normally an optimization to prevent an unnecessary copy when an argument is
         // not mutated by the current function, this is necessary to support unsized arguments.
         if let ArgKind::Normal(Some(val)) = arg_kind {
@@ -300,6 +296,8 @@ pub(crate) fn codegen_fn_prelude<'tcx>(fx: &mut FunctionCx<'_, '_, 'tcx>, start_
             }
         }
 
+        let layout = fx.layout_of(ty);
+        let is_ssa = ssa_analyzed[local].is_ssa(fx, ty);
         let place = make_local_place(fx, local, layout, is_ssa);
         assert_eq!(fx.local_map.push(place), local);
 
@@ -323,7 +321,7 @@ pub(crate) fn codegen_fn_prelude<'tcx>(fx: &mut FunctionCx<'_, '_, 'tcx>, start_
         let ty = fx.monomorphize(fx.mir.local_decls[local].ty);
         let layout = fx.layout_of(ty);
 
-        let is_ssa = ssa_analyzed[local] == crate::analyze::SsaKind::Ssa;
+        let is_ssa = ssa_analyzed[local].is_ssa(fx, ty);
 
         let place = make_local_place(fx, local, layout, is_ssa);
         assert_eq!(fx.local_map.push(place), local);
diff --git a/src/abi/returning.rs b/src/abi/returning.rs
index aaa1418767a..6d3e8eda276 100644
--- a/src/abi/returning.rs
+++ b/src/abi/returning.rs
@@ -14,7 +14,8 @@ pub(super) fn codegen_return_param<'tcx>(
 ) -> CPlace<'tcx> {
     let (ret_place, ret_param): (_, SmallVec<[_; 2]>) = match fx.fn_abi.as_ref().unwrap().ret.mode {
         PassMode::Ignore | PassMode::Direct(_) | PassMode::Pair(_, _) | PassMode::Cast(..) => {
-            let is_ssa = ssa_analyzed[RETURN_PLACE] == crate::analyze::SsaKind::Ssa;
+            let is_ssa =
+                ssa_analyzed[RETURN_PLACE].is_ssa(fx, fx.fn_abi.as_ref().unwrap().ret.layout.ty);
             (
                 super::make_local_place(
                     fx,
diff --git a/src/analyze.rs b/src/analyze.rs
index 0cbb9f3ec2d..54d5c1c2ae9 100644
--- a/src/analyze.rs
+++ b/src/analyze.rs
@@ -4,34 +4,30 @@ use crate::prelude::*;
 
 use rustc_index::vec::IndexVec;
 use rustc_middle::mir::StatementKind::*;
+use rustc_middle::ty::Ty;
 
 #[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
 pub(crate) enum SsaKind {
     NotSsa,
-    Ssa,
+    MaybeSsa,
+}
+
+impl SsaKind {
+    pub(crate) fn is_ssa<'tcx>(self, fx: &FunctionCx<'_, '_, 'tcx>, ty: Ty<'tcx>) -> bool {
+        self == SsaKind::MaybeSsa && (fx.clif_type(ty).is_some() || fx.clif_pair_type(ty).is_some())
+    }
 }
 
 pub(crate) fn analyze(fx: &FunctionCx<'_, '_, '_>) -> IndexVec<Local, SsaKind> {
-    let mut flag_map = fx
-        .mir
-        .local_decls
-        .iter()
-        .map(|local_decl| {
-            let ty = fx.monomorphize(local_decl.ty);
-            if fx.clif_type(ty).is_some() || fx.clif_pair_type(ty).is_some() {
-                SsaKind::Ssa
-            } else {
-                SsaKind::NotSsa
-            }
-        })
-        .collect::<IndexVec<Local, SsaKind>>();
+    let mut flag_map =
+        fx.mir.local_decls.iter().map(|_| SsaKind::MaybeSsa).collect::<IndexVec<Local, SsaKind>>();
 
     for bb in fx.mir.basic_blocks.iter() {
         for stmt in bb.statements.iter() {
             match &stmt.kind {
                 Assign(place_and_rval) => match &place_and_rval.1 {
                     Rvalue::Ref(_, _, place) | Rvalue::AddressOf(_, place) => {
-                        not_ssa(&mut flag_map, place.local)
+                        flag_map[place.local] = SsaKind::NotSsa;
                     }
                     _ => {}
                 },
@@ -42,7 +38,3 @@ pub(crate) fn analyze(fx: &FunctionCx<'_, '_, '_>) -> IndexVec<Local, SsaKind> {
 
     flag_map
 }
-
-fn not_ssa(flag_map: &mut IndexVec<Local, SsaKind>, local: Local) {
-    flag_map[local] = SsaKind::NotSsa;
-}