Auto merge of #65989 - Aaron1011:fix/normalize-param-env, r=nikomatsakis

[rust.git] / src / librustc_middle / ty / layout.rs

diff --git a/src/librustc_middle/ty/layout.rs b/src/librustc_middle/ty/layout.rs
index 06dd2eee50567282a6c2f07862047e8f9c1e26d1..143d3c4e1e92bcb2b8c438257d2868272c70c640 100644 (file)
--- a/src/librustc_middle/ty/layout.rs
+++ b/src/librustc_middle/ty/layout.rs
@@ -876,8 +876,6 @@ fn layout_raw_uncached(&self, ty: Ty<'tcx>) -> Result<&'tcx Layout, LayoutError<
                     .iter_enumerated()
                     .all(|(i, v)| v.discr == ty::VariantDiscr::Relative(i.as_u32()));
 
-                let mut niche_filling_layout = None;
-
                 // Niche-filling enum optimization.
                 if !def.repr.inhibit_enum_layout_opt() && no_explicit_discriminants {
                     let mut dataful_variant = None;
@@ -974,7 +972,7 @@ fn layout_raw_uncached(&self, ty: Ty<'tcx>) -> Result<&'tcx Layout, LayoutError<
                             let largest_niche =
                                 Niche::from_scalar(dl, offset, niche_scalar.clone());
 
-                            niche_filling_layout = Some(Layout {
+                            return Ok(tcx.intern_layout(Layout {
                                 variants: Variants::Multiple {
                                     tag: niche_scalar,
                                     tag_encoding: TagEncoding::Niche {
@@ -993,7 +991,7 @@ fn layout_raw_uncached(&self, ty: Ty<'tcx>) -> Result<&'tcx Layout, LayoutError<
                                 largest_niche,
                                 size,
                                 align,
-                            });
+                            }));
                         }
                     }
                 }
@@ -1216,7 +1214,7 @@ fn layout_raw_uncached(&self, ty: Ty<'tcx>) -> Result<&'tcx Layout, LayoutError<
 
                 let largest_niche = Niche::from_scalar(dl, Size::ZERO, tag.clone());
 
-                let tagged_layout = Layout {
+                tcx.intern_layout(Layout {
                     variants: Variants::Multiple {
                         tag,
                         tag_encoding: TagEncoding::Direct,
@@ -1231,23 +1229,7 @@ fn layout_raw_uncached(&self, ty: Ty<'tcx>) -> Result<&'tcx Layout, LayoutError<
                     abi,
                     align,
                     size,
-                };
-
-                let best_layout = match (tagged_layout, niche_filling_layout) {
-                    (tagged_layout, Some(niche_filling_layout)) => {
-                        // Pick the smaller layout; otherwise,
-                        // pick the layout with the larger niche; otherwise,
-                        // pick tagged as it has simpler codegen.
-                        cmp::min_by_key(tagged_layout, niche_filling_layout, |layout| {
-                            let niche_size =
-                                layout.largest_niche.as_ref().map_or(0, |n| n.available(dl));
-                            (layout.size, cmp::Reverse(niche_size))
-                        })
-                    }
-                    (tagged_layout, None) => tagged_layout,
-                };
-
-                tcx.intern_layout(best_layout)
+                })
             }
 
             // Types with no meaningful known layout.
@@ -2166,16 +2148,31 @@ fn field(this: TyAndLayout<'tcx>, cx: &C, i: usize) -> C::TyAndLayout {
     }
 
     fn pointee_info_at(this: TyAndLayout<'tcx>, cx: &C, offset: Size) -> Option<PointeeInfo> {
-        match this.ty.kind {
+        let addr_space_of_ty = |ty: Ty<'tcx>| {
+            if ty.is_fn() { cx.data_layout().instruction_address_space } else { AddressSpace::DATA }
+        };
+
+        let pointee_info = match this.ty.kind {
             ty::RawPtr(mt) if offset.bytes() == 0 => {
                 cx.layout_of(mt.ty).to_result().ok().map(|layout| PointeeInfo {
                     size: layout.size,
                     align: layout.align.abi,
                     safe: None,
+                    address_space: addr_space_of_ty(mt.ty),
+                })
+            }
+            ty::FnPtr(fn_sig) if offset.bytes() == 0 => {
+                cx.layout_of(cx.tcx().mk_fn_ptr(fn_sig)).to_result().ok().map(|layout| {
+                    PointeeInfo {
+                        size: layout.size,
+                        align: layout.align.abi,
+                        safe: None,
+                        address_space: cx.data_layout().instruction_address_space,
+                    }
                 })
             }
-
             ty::Ref(_, ty, mt) if offset.bytes() == 0 => {
+                let address_space = addr_space_of_ty(ty);
                 let tcx = cx.tcx();
                 let is_freeze = ty.is_freeze(tcx.at(DUMMY_SP), cx.param_env());
                 let kind = match mt {
@@ -2210,6 +2207,7 @@ fn pointee_info_at(this: TyAndLayout<'tcx>, cx: &C, offset: Size) -> Option<Poin
                     size: layout.size,
                     align: layout.align.abi,
                     safe: Some(kind),
+                    address_space,
                 })
             }
 
@@ -2254,7 +2252,9 @@ fn pointee_info_at(this: TyAndLayout<'tcx>, cx: &C, offset: Size) -> Option<Poin
                             result = field.to_result().ok().and_then(|field| {
                                 if ptr_end <= field_start + field.size {
                                     // We found the right field, look inside it.
-                                    field.pointee_info_at(cx, offset - field_start)
+                                    let field_info =
+                                        field.pointee_info_at(cx, offset - field_start);
+                                    field_info
                                 } else {
                                     None
                                 }
@@ -2277,7 +2277,14 @@ fn pointee_info_at(this: TyAndLayout<'tcx>, cx: &C, offset: Size) -> Option<Poin
 
                 result
             }
-        }
+        };
+
+        debug!(
+            "pointee_info_at (offset={:?}, type kind: {:?}) => {:?}",
+            offset, this.ty.kind, pointee_info
+        );
+
+        pointee_info
     }
 }