rustc_trans: use more of the trans::mir and ty::layout APIs throughout.

22 files changed, 706 insertions, 885 deletions

diff --git a/src/librustc/ty/layout.rs b/src/librustc/ty/layout.rs
index d83f7e661ba..d51c25ba6d3 100644
--- a/src/librustc/ty/layout.rs
+++ b/src/librustc/ty/layout.rs
@@ -1700,6 +1700,10 @@ impl<'a, 'tcx> Layout {
         }
     }
 
+    pub fn size_and_align<C: HasDataLayout>(&self, cx: C) -> (Size, Align) {
+        (self.size(cx), self.align(cx))
+    }
+
     /// Returns alignment before repr alignment is applied
     pub fn primitive_align<C: HasDataLayout>(&self, cx: C) -> Align {
         match *self {
@@ -2201,6 +2205,11 @@ impl<'a, 'tcx> LayoutTyper<'tcx> for LayoutCx<'a, 'tcx> {
 
 impl<'a, 'tcx> TyLayout<'tcx> {
     pub fn for_variant(&self, variant_index: usize) -> Self {
+        let is_enum = match self.ty.sty {
+            ty::TyAdt(def, _) => def.is_enum(),
+            _ => false
+        };
+        assert!(is_enum);
         TyLayout {
             variant_index: Some(variant_index),
             ..*self
@@ -2214,13 +2223,26 @@ impl<'a, 'tcx> TyLayout<'tcx> {
     pub fn field_count(&self) -> usize {
         // Handle enum/union through the type rather than Layout.
         if let ty::TyAdt(def, _) = self.ty.sty {
-            let v = self.variant_index.unwrap_or(0);
-            if def.variants.is_empty() {
-                assert_eq!(v, 0);
-                return 0;
+            let v = if def.is_enum() {
+                if def.variants.is_empty() {
+                    return 0;
+                }
+                match self.variant_index {
+                    None => match *self.layout {
+                        // Discriminant field for enums (where applicable).
+                        General { .. } => return 1,
+                        _ if def.variants.len() > 1 => return 0,
+
+                        // Enums with one variant behave like structs.
+                        _ => 0
+                    },
+                    Some(v) => v
+                }
             } else {
-                return def.variants[v].fields.len();
-            }
+                0
+            };
+
+            return def.variants[v].fields.len();
         }
 
         match *self.layout {
@@ -2248,7 +2270,7 @@ impl<'a, 'tcx> TyLayout<'tcx> {
         }
     }
 
-    pub fn field_type<C: LayoutTyper<'tcx>>(&self, cx: C, i: usize) -> Ty<'tcx> {
+    fn field_type_unnormalized<C: LayoutTyper<'tcx>>(&self, cx: C, i: usize) -> Ty<'tcx> {
         let tcx = cx.tcx();
 
         let ptr_field_type = |pointee: Ty<'tcx>| {
@@ -2314,7 +2336,25 @@ impl<'a, 'tcx> TyLayout<'tcx> {
 
             // ADTs.
             ty::TyAdt(def, substs) => {
-                def.variants[self.variant_index.unwrap_or(0)].fields[i].ty(tcx, substs)
+                let v = if def.is_enum() {
+                    match self.variant_index {
+                        None => match *self.layout {
+                            // Discriminant field for enums (where applicable).
+                            General { discr, .. } => {
+                                return [discr.to_ty(tcx, false)][i];
+                            }
+                            _ if def.variants.len() > 1 => return [][i],
+
+                            // Enums with one variant behave like structs.
+                            _ => 0
+                        },
+                        Some(v) => v
+                    }
+                } else {
+                    0
+                };
+
+                def.variants[v].fields[i].ty(tcx, substs)
             }
 
             ty::TyProjection(_) | ty::TyAnon(..) | ty::TyParam(_) |
@@ -2324,11 +2364,15 @@ impl<'a, 'tcx> TyLayout<'tcx> {
         }
     }
 
+    pub fn field_type<C: LayoutTyper<'tcx>>(&self, cx: C, i: usize) -> Ty<'tcx> {
+        cx.normalize_projections(self.field_type_unnormalized(cx, i))
+    }
+
     pub fn field<C: LayoutTyper<'tcx>>(&self,
                                        cx: C,
                                        i: usize)
                                        -> C::TyLayout {
-        cx.layout_of(cx.normalize_projections(self.field_type(cx, i)))
+        cx.layout_of(self.field_type(cx, i))
     }
 }
 
diff --git a/src/librustc_trans/abi.rs b/src/librustc_trans/abi.rs
index ffbc4f82bca..04041488016 100644
--- a/src/librustc_trans/abi.rs
+++ b/src/librustc_trans/abi.rs
@@ -30,6 +30,7 @@ use cabi_sparc64;
 use cabi_nvptx;
 use cabi_nvptx64;
 use cabi_hexagon;
+use mir::lvalue::LvalueRef;
 use type_::Type;
 use type_of;
 
@@ -570,20 +571,20 @@ impl<'a, 'tcx> ArgType<'tcx> {
     /// lvalue for the original Rust type of this argument/return.
     /// Can be used for both storing formal arguments into Rust variables
     /// or results of call/invoke instructions into their destinations.
-    pub fn store(&self, bcx: &Builder<'a, 'tcx>, mut val: ValueRef, dst: ValueRef) {
+    pub fn store(&self, bcx: &Builder<'a, 'tcx>, mut val: ValueRef, dst: LvalueRef<'tcx>) {
         if self.is_ignore() {
             return;
         }
         let ccx = bcx.ccx;
         if self.is_indirect() {
             let llsz = C_usize(ccx, self.layout.size(ccx).bytes());
-            base::call_memcpy(bcx, dst, val, llsz, self.layout.align(ccx));
+            base::call_memcpy(bcx, dst.llval, val, llsz, self.layout.align(ccx));
         } else if let Some(ty) = self.cast {
             // FIXME(eddyb): Figure out when the simpler Store is safe, clang
             // uses it for i16 -> {i8, i8}, but not for i24 -> {i8, i8, i8}.
             let can_store_through_cast_ptr = false;
             if can_store_through_cast_ptr {
-                let cast_dst = bcx.pointercast(dst, ty.llvm_type(ccx).ptr_to());
+                let cast_dst = bcx.pointercast(dst.llval, ty.llvm_type(ccx).ptr_to());
                 bcx.store(val, cast_dst, Some(self.layout.align(ccx)));
             } else {
                 // The actual return type is a struct, but the ABI
@@ -610,7 +611,7 @@ impl<'a, 'tcx> ArgType<'tcx> {
 
                 // ...and then memcpy it to the intended destination.
                 base::call_memcpy(bcx,
-                                  bcx.pointercast(dst, Type::i8p(ccx)),
+                                  bcx.pointercast(dst.llval, Type::i8p(ccx)),
                                   bcx.pointercast(llscratch, Type::i8p(ccx)),
                                   C_usize(ccx, self.layout.size(ccx).bytes()),
                                   self.layout.align(ccx).min(ty.align(ccx)));
@@ -618,14 +619,12 @@ impl<'a, 'tcx> ArgType<'tcx> {
                 bcx.lifetime_end(llscratch, scratch_size);
             }
         } else {
-            if self.layout.ty == ccx.tcx().types.bool {
-                val = bcx.zext(val, Type::i8(ccx));
-            }
-            bcx.store(val, dst, None);
+            val = base::from_immediate(bcx, val);
+            bcx.store(val, dst.llval, None);
         }
     }
 
-    pub fn store_fn_arg(&self, bcx: &Builder<'a, 'tcx>, idx: &mut usize, dst: ValueRef) {
+    pub fn store_fn_arg(&self, bcx: &Builder<'a, 'tcx>, idx: &mut usize, dst: LvalueRef<'tcx>) {
         if self.pad.is_some() {
             *idx += 1;
         }
diff --git a/src/librustc_trans/adt.rs b/src/librustc_trans/adt.rs
index 9d693e098cf..2383b372865 100644
--- a/src/librustc_trans/adt.rs
+++ b/src/librustc_trans/adt.rs
@@ -42,10 +42,9 @@
 //!   taken to it, implementing them for Rust seems difficult.
 
 use rustc::ty::{self, Ty};
-use rustc::ty::layout::{self, Align, HasDataLayout, LayoutTyper, Size};
+use rustc::ty::layout::{self, Align, HasDataLayout, LayoutTyper, Size, TyLayout};
 
 use context::CrateContext;
-use monomorphize;
 use type_::Type;
 use type_of;
 
@@ -75,15 +74,25 @@ pub fn finish_type_of<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
         | layout::UntaggedUnion { .. } | layout::RawNullablePointer { .. } => { }
         layout::Univariant { ..}
         | layout::StructWrappedNullablePointer { .. } => {
-            let (nonnull_variant_index, nonnull_variant, packed) = match *l {
-                layout::Univariant { ref variant, .. } => (0, variant, variant.packed),
+            let (variant_layout, variant) = match *l {
+                layout::Univariant { ref variant, .. } => {
+                    let is_enum = if let ty::TyAdt(def, _) = t.sty {
+                        def.is_enum()
+                    } else {
+                        false
+                    };
+                    if is_enum {
+                        (l.for_variant(0), variant)
+                    } else {
+                        (l, variant)
+                    }
+                }
                 layout::StructWrappedNullablePointer { nndiscr, ref nonnull, .. } =>
-                    (nndiscr, nonnull, nonnull.packed),
+                    (l.for_variant(nndiscr as usize), nonnull),
                 _ => unreachable!()
             };
-            llty.set_struct_body(&struct_llfields(cx, t, nonnull_variant_index as usize,
-                                                  nonnull_variant, None),
-                                 packed)
+            llty.set_struct_body(&struct_llfields(cx, variant_layout, variant, None),
+                                 variant.packed)
         },
         _ => bug!("This function cannot handle {} with layout {:#?}", t, l)
     }
@@ -97,22 +106,18 @@ fn generic_type_of<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
     match *l {
         layout::CEnum { discr, .. } => Type::from_integer(cx, discr),
         layout::RawNullablePointer { nndiscr, .. } => {
-            let (def, substs) = match t.sty {
-                ty::TyAdt(d, s) => (d, s),
-                _ => bug!("{} is not an ADT", t)
-            };
-            let nnty = monomorphize::field_ty(cx.tcx(), substs,
-                &def.variants[nndiscr as usize].fields[0]);
-            if let layout::Scalar { value: layout::Pointer, .. } = *cx.layout_of(nnty) {
+            let nnfield = l.for_variant(nndiscr as usize).field(cx, 0);
+            if let layout::Scalar { value: layout::Pointer, .. } = *nnfield {
                 Type::i8p(cx)
             } else {
-                type_of::type_of(cx, nnty)
+                type_of::type_of(cx, nnfield.ty)
             }
         }
         layout::StructWrappedNullablePointer { nndiscr, ref nonnull, .. } => {
             match name {
                 None => {
-                    Type::struct_(cx, &struct_llfields(cx, t, nndiscr as usize, nonnull, None),
+                    Type::struct_(cx, &struct_llfields(cx, l.for_variant(nndiscr as usize),
+                                                       nonnull, None),
                                   nonnull.packed)
                 }
                 Some(name) => {
@@ -123,7 +128,7 @@ fn generic_type_of<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
         layout::Univariant { ref variant, .. } => {
             match name {
                 None => {
-                    Type::struct_(cx, &struct_llfields(cx, t, 0, &variant, None),
+                    Type::struct_(cx, &struct_llfields(cx, l, &variant, None),
                                   variant.packed)
                 }
                 Some(name) => {
@@ -199,61 +204,30 @@ fn union_fill(cx: &CrateContext, size: Size, align: Align) -> Type {
 }
 
 /// Double an index to account for padding.
-pub fn memory_index_to_gep(index: usize) -> usize {
+pub fn memory_index_to_gep(index: u64) -> u64 {
     index * 2
 }
 
-/// Lookup `Struct::memory_index`, double it to account for padding.
-pub fn struct_llfields_index(variant: &layout::Struct, index: usize) -> usize {
-    memory_index_to_gep(variant.memory_index[index] as usize)
-}
-
 pub fn struct_llfields<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
-                                 t: Ty<'tcx>,
-                                 variant_index: usize,
+                                 layout: TyLayout<'tcx>,
                                  variant: &layout::Struct,
                                  discr: Option<Ty<'tcx>>) -> Vec<Type> {
-    let field_count = match t.sty {
-        ty::TyAdt(ref def, _) if def.variants.len() == 0 => return vec![],
-        ty::TyAdt(ref def, _) => {
-            discr.is_some() as usize + def.variants[variant_index].fields.len()
-        },
-        ty::TyTuple(fields, _) => fields.len(),
-        ty::TyClosure(def_id, substs) => {
-            if variant_index > 0 { bug!("{} is a closure, which only has one variant", t);}
-            substs.upvar_tys(def_id, cx.tcx()).count()
-        },
-        ty::TyGenerator(def_id, substs, _) => {
-            if variant_index > 0 { bug!("{} is a generator, which only has one variant", t);}
-            substs.field_tys(def_id, cx.tcx()).count()
-        },
-        _ => bug!("{} is not a type that can have fields.", t)
-    };
+    let field_count = (discr.is_some() as usize) + layout.field_count();
     debug!("struct_llfields: variant: {:?}", variant);
     let mut first_field = true;
     let mut offset = Size::from_bytes(0);
     let mut result: Vec<Type> = Vec::with_capacity(field_count * 2);
     let field_iter = variant.field_index_by_increasing_offset().map(|i| {
-        (i, match t.sty {
-            ty::TyAdt(..) if i == 0 && discr.is_some() => discr.unwrap(),
-            ty::TyAdt(ref def, ref substs) => {
-                monomorphize::field_ty(cx.tcx(), substs,
-                    &def.variants[variant_index].fields[i as usize - discr.is_some() as usize])
-            },
-            ty::TyTuple(fields, _) => fields[i as usize],
-            ty::TyClosure(def_id, substs) => {
-                substs.upvar_tys(def_id, cx.tcx()).nth(i).unwrap()
-            },
-            ty::TyGenerator(def_id, substs, _) => {
-                let ty = substs.field_tys(def_id, cx.tcx()).nth(i).unwrap();
-                cx.tcx().normalize_associated_type(&ty)
-            },
-            _ => bug!()
-        }, variant.offsets[i as usize])
+        let ty = if i == 0 && discr.is_some() {
+            cx.layout_of(discr.unwrap())
+        } else {
+            layout.field(cx, i - discr.is_some() as usize)
+        };
+        (i, ty, variant.offsets[i as usize])
     });
-    for (index, ty, target_offset) in field_iter {
-        debug!("struct_llfields: {} ty: {} offset: {:?} target_offset: {:?}",
-            index, ty, offset, target_offset);
+    for (index, field, target_offset) in field_iter {
+        debug!("struct_llfields: {}: {:?} offset: {:?} target_offset: {:?}",
+            index, field, offset, target_offset);
         assert!(target_offset >= offset);
         let padding = target_offset - offset;
         if first_field {
@@ -263,19 +237,19 @@ pub fn struct_llfields<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
             result.push(Type::array(&Type::i8(cx), padding.bytes()));
             debug!("    padding before: {:?}", padding);
         }
-        let llty = type_of::in_memory_type_of(cx, ty);
+        let llty = type_of::in_memory_type_of(cx, field.ty);
         result.push(llty);
-        let layout = cx.layout_of(ty);
+
         if variant.packed {
             assert_eq!(padding.bytes(), 0);
         } else {
-            let field_align = layout.align(cx);
+            let field_align = field.align(cx);
             assert!(field_align.abi() <= variant.align.abi(),
                     "non-packed type has field with larger align ({}): {:#?}",
                     field_align.abi(), variant);
         }
-        let target_size = layout.size(&cx.tcx().data_layout);
-        offset = target_offset + target_size;
+
+        offset = target_offset + field.size(cx);
     }
     if variant.sized && field_count > 0 {
         if offset > variant.stride() {
diff --git a/src/librustc_trans/asm.rs b/src/librustc_trans/asm.rs
index 92cbd004206..e6199df62d3 100644
--- a/src/librustc_trans/asm.rs
+++ b/src/librustc_trans/asm.rs
@@ -11,7 +11,6 @@
 //! # Translation of inline assembly.
 
 use llvm::{self, ValueRef};
-use base;
 use common::*;
 use type_of;
 use type_::Type;
@@ -19,8 +18,9 @@ use builder::Builder;
 
 use rustc::hir;
 use rustc::ty::Ty;
+use rustc::ty::layout::Align;
 
-use mir::lvalue::Alignment;
+use mir::lvalue::{LvalueRef, Alignment};
 
 use std::ffi::CString;
 use syntax::ast::AsmDialect;
@@ -40,16 +40,17 @@ pub fn trans_inline_asm<'a, 'tcx>(
     let mut indirect_outputs = vec![];
     for (i, (out, &(val, ty))) in ia.outputs.iter().zip(&outputs).enumerate() {
         let val = if out.is_rw || out.is_indirect {
-            Some(base::load_ty(bcx, val, Alignment::Packed, ty))
+            Some(LvalueRef::new_sized(val, ty,
+                Alignment::Packed(Align::from_bytes(1, 1).unwrap())).load(bcx))
         } else {
             None
         };
         if out.is_rw {
-            inputs.push(val.unwrap());
+            inputs.push(val.unwrap().immediate());
             ext_constraints.push(i.to_string());
         }
         if out.is_indirect {
-            indirect_outputs.push(val.unwrap());
+            indirect_outputs.push(val.unwrap().immediate());
         } else {
             output_types.push(type_of::type_of(bcx.ccx, ty));
         }
@@ -107,7 +108,7 @@ pub fn trans_inline_asm<'a, 'tcx>(
     // Again, based on how many outputs we have
     let outputs = ia.outputs.iter().zip(&outputs).filter(|&(ref o, _)| !o.is_indirect);
     for (i, (_, &(val, _))) in outputs.enumerate() {
-        let v = if num_outputs == 1 { r } else { bcx.extract_value(r, i) };
+        let v = if num_outputs == 1 { r } else { bcx.extract_value(r, i as u64) };
         bcx.store(v, val, None);
     }
 
diff --git a/src/librustc_trans/base.rs b/src/librustc_trans/base.rs
index 98ad6a54bd1..91f7bf39f1a 100644
--- a/src/librustc_trans/base.rs
+++ b/src/librustc_trans/base.rs
@@ -48,7 +48,6 @@ use rustc::util::common::{time, print_time_passes_entry};
 use rustc::session::config::{self, NoDebugInfo};
 use rustc::session::Session;
 use rustc_incremental;
-use abi;
 use allocator;
 use mir::lvalue::LvalueRef;
 use attributes;
@@ -56,7 +55,7 @@ use builder::Builder;
 use callee;
 use common::{C_bool, C_bytes_in_context, C_i32, C_usize};
 use collector::{self, TransItemCollectionMode};
-use common::{C_struct_in_context, C_undef, C_array};
+use common::{C_struct_in_context, C_array};
 use common::CrateContext;
 use common::{type_is_zero_size, val_ty};
 use common;
@@ -66,14 +65,13 @@ use debuginfo;
 use declare;
 use meth;
 use mir;
-use monomorphize::{self, Instance};
+use monomorphize::Instance;
 use partitioning::{self, PartitioningStrategy, CodegenUnit, CodegenUnitExt};
 use symbol_names_test;
 use time_graph;
 use trans_item::{TransItem, BaseTransItemExt, TransItemExt, DefPathBasedNames};
 use type_::Type;
 use type_of;
-use value::Value;
 use rustc::util::nodemap::{NodeSet, FxHashMap, FxHashSet, DefIdSet};
 use CrateInfo;
 
@@ -90,7 +88,7 @@ use syntax::attr;
 use rustc::hir;
 use syntax::ast;
 
-use mir::lvalue::Alignment;
+use mir::operand::{OperandRef, OperandValue};
 
 pub use rustc_trans_utils::{find_exported_symbols, check_for_rustc_errors_attr};
 pub use rustc_trans_utils::trans_item::linkage_by_name;
@@ -125,14 +123,6 @@ impl<'a, 'tcx> Drop for StatRecorder<'a, 'tcx> {
     }
 }
 
-pub fn get_meta(bcx: &Builder, fat_ptr: ValueRef) -> ValueRef {
-    bcx.struct_gep(fat_ptr, abi::FAT_PTR_EXTRA)
-}
-
-pub fn get_dataptr(bcx: &Builder, fat_ptr: ValueRef) -> ValueRef {
-    bcx.struct_gep(fat_ptr, abi::FAT_PTR_ADDR)
-}
-
 pub fn bin_op_to_icmp_predicate(op: hir::BinOp_,
                                 signed: bool)
                                 -> llvm::IntPredicate {
@@ -257,25 +247,29 @@ pub fn unsize_thin_ptr<'a, 'tcx>(
 /// Coerce `src`, which is a reference to a value of type `src_ty`,
 /// to a value of type `dst_ty` and store the result in `dst`
 pub fn coerce_unsized_into<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
-                                     src: &LvalueRef<'tcx>,
-                                     dst: &LvalueRef<'tcx>) {
+                                     src: LvalueRef<'tcx>,
+                                     dst: LvalueRef<'tcx>) {
     let src_ty = src.ty.to_ty(bcx.tcx());
     let dst_ty = dst.ty.to_ty(bcx.tcx());
     let coerce_ptr = || {
-        let (base, info) = if common::type_is_fat_ptr(bcx.ccx, src_ty) {
-            // fat-ptr to fat-ptr unsize preserves the vtable
-            // i.e. &'a fmt::Debug+Send => &'a fmt::Debug
-            // So we need to pointercast the base to ensure
-            // the types match up.
-            let (base, info) = load_fat_ptr(bcx, src.llval, src.alignment, src_ty);
-            let llcast_ty = type_of::fat_ptr_base_ty(bcx.ccx, dst_ty);
-            let base = bcx.pointercast(base, llcast_ty);
-            (base, info)
-        } else {
-            let base = load_ty(bcx, src.llval, src.alignment, src_ty);
-            unsize_thin_ptr(bcx, base, src_ty, dst_ty)
+        let (base, info) = match src.load(bcx).val {
+            OperandValue::Pair(base, info) => {
+                // fat-ptr to fat-ptr unsize preserves the vtable
+                // i.e. &'a fmt::Debug+Send => &'a fmt::Debug
+                // So we need to pointercast the base to ensure
+                // the types match up.
+                let llcast_ty = type_of::fat_ptr_base_ty(bcx.ccx, dst_ty);
+                (bcx.pointercast(base, llcast_ty), info)
+            }
+            OperandValue::Immediate(base) => {
+                unsize_thin_ptr(bcx, base, src_ty, dst_ty)
+            }
+            OperandValue::Ref(..) => bug!()
         };
-        store_fat_ptr(bcx, base, info, dst.llval, dst.alignment, dst_ty);
+        OperandRef {
+            val: OperandValue::Pair(base, info),
+            ty: dst_ty
+        }.store(bcx, dst);
     };
     match (&src_ty.sty, &dst_ty.sty) {
         (&ty::TyRef(..), &ty::TyRef(..)) |
@@ -287,32 +281,25 @@ pub fn coerce_unsized_into<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
             coerce_ptr()
         }
 
-        (&ty::TyAdt(def_a, substs_a), &ty::TyAdt(def_b, substs_b)) => {
+        (&ty::TyAdt(def_a, _), &ty::TyAdt(def_b, _)) => {
             assert_eq!(def_a, def_b);
 
-            let src_fields = def_a.variants[0].fields.iter().map(|f| {
-                monomorphize::field_ty(bcx.tcx(), substs_a, f)
-            });
-            let dst_fields = def_b.variants[0].fields.iter().map(|f| {
-                monomorphize::field_ty(bcx.tcx(), substs_b, f)
-            });
+            for i in 0..def_a.variants[0].fields.len() {
+                let src_f = src.project_field(bcx, i);
+                let dst_f = dst.project_field(bcx, i);
+
+                let src_f_ty = src_f.ty.to_ty(bcx.tcx());
+                let dst_f_ty = dst_f.ty.to_ty(bcx.tcx());
 
-            let iter = src_fields.zip(dst_fields).enumerate();
-            for (i, (src_fty, dst_fty)) in iter {
-                if type_is_zero_size(bcx.ccx, dst_fty) {
+                if type_is_zero_size(bcx.ccx, dst_f_ty) {
                     continue;
                 }
 
-                let (src_f, src_f_align) = src.trans_field_ptr(bcx, i);
-                let (dst_f, dst_f_align) = dst.trans_field_ptr(bcx, i);
-                if src_fty == dst_fty {
-                    memcpy_ty(bcx, dst_f, src_f, src_fty, None);
+                if src_f_ty == dst_f_ty {
+                    memcpy_ty(bcx, dst_f.llval, src_f.llval, src_f_ty,
+                        (src_f.alignment | dst_f.alignment).non_abi());
                 } else {
-                    coerce_unsized_into(
-                        bcx,
-                        &LvalueRef::new_sized_ty(src_f, src_fty, src_f_align),
-                        &LvalueRef::new_sized_ty(dst_f, dst_fty, dst_f_align)
-                    );
+                    coerce_unsized_into(bcx, src_f, dst_f);
                 }
             }
         }
@@ -385,94 +372,6 @@ pub fn call_assume<'a, 'tcx>(b: &Builder<'a, 'tcx>, val: ValueRef) {
     b.call(assume_intrinsic, &[val], None);
 }
 
-/// Helper for loading values from memory. Does the necessary conversion if the in-memory type
-/// differs from the type used for SSA values. Also handles various special cases where the type
-/// gives us better information about what we are loading.
-pub fn load_ty<'a, 'tcx>(b: &Builder<'a, 'tcx>, ptr: ValueRef,
-                         alignment: Alignment, t: Ty<'tcx>) -> ValueRef {
-    let ccx = b.ccx;
-    if type_is_zero_size(ccx, t) {
-        return C_undef(type_of::type_of(ccx, t));
-    }
-
-    unsafe {
-        let global = llvm::LLVMIsAGlobalVariable(ptr);
-        if !global.is_null() && llvm::LLVMIsGlobalConstant(global) == llvm::True {
-            let val = llvm::LLVMGetInitializer(global);
-            if !val.is_null() {
-                if t.is_bool() {
-                    return llvm::LLVMConstTrunc(val, Type::i1(ccx).to_ref());
-                }
-                return val;
-            }
-        }
-    }
-
-    if t.is_bool() {
-        b.trunc(b.load_range_assert(ptr, 0, 2, llvm::False, alignment.to_align()),
-                Type::i1(ccx))
-    } else if t.is_char() {
-        // a char is a Unicode codepoint, and so takes values from 0
-        // to 0x10FFFF inclusive only.
-        b.load_range_assert(ptr, 0, 0x10FFFF + 1, llvm::False, alignment.to_align())
-    } else if (t.is_region_ptr() || t.is_box() || t.is_fn())
-        && !common::type_is_fat_ptr(ccx, t)
-    {
-        b.load_nonnull(ptr, alignment.to_align())
-    } else {
-        b.load(ptr, alignment.to_align())
-    }
-}
-
-/// Helper for storing values in memory. Does the necessary conversion if the in-memory type
-/// differs from the type used for SSA values.
-pub fn store_ty<'a, 'tcx>(cx: &Builder<'a, 'tcx>, v: ValueRef, dst: ValueRef,
-                          dst_align: Alignment, t: Ty<'tcx>) {
-    debug!("store_ty: {:?} : {:?} <- {:?}", Value(dst), t, Value(v));
-
-    if common::type_is_fat_ptr(cx.ccx, t) {
-        let lladdr = cx.extract_value(v, abi::FAT_PTR_ADDR);
-        let llextra = cx.extract_value(v, abi::FAT_PTR_EXTRA);
-        store_fat_ptr(cx, lladdr, llextra, dst, dst_align, t);
-    } else {
-        cx.store(from_immediate(cx, v), dst, dst_align.to_align());
-    }
-}
-
-pub fn store_fat_ptr<'a, 'tcx>(cx: &Builder<'a, 'tcx>,
-                               data: ValueRef,
-                               extra: ValueRef,
-                               dst: ValueRef,
-                               dst_align: Alignment,
-                               _ty: Ty<'tcx>) {
-    // FIXME: emit metadata
-    cx.store(data, get_dataptr(cx, dst), dst_align.to_align());
-    cx.store(extra, get_meta(cx, dst), dst_align.to_align());
-}
-
-pub fn load_fat_ptr<'a, 'tcx>(
-    b: &Builder<'a, 'tcx>, src: ValueRef, alignment: Alignment, t: Ty<'tcx>
-) -> (ValueRef, ValueRef) {
-    let ptr = get_dataptr(b, src);
-    let ptr = if t.is_region_ptr() || t.is_box() {
-        b.load_nonnull(ptr, alignment.to_align())
-    } else {
-        b.load(ptr, alignment.to_align())
-    };
-
-    let meta = get_meta(b, src);
-    let meta_ty = val_ty(meta);
-    // If the 'meta' field is a pointer, it's a vtable, so use load_nonnull
-    // instead
-    let meta = if meta_ty.element_type().kind() == llvm::TypeKind::Pointer {
-        b.load_nonnull(meta, None)
-    } else {
-        b.load(meta, None)
-    };
-
-    (ptr, meta)
-}
-
 pub fn from_immediate(bcx: &Builder, val: ValueRef) -> ValueRef {
     if val_ty(val) == Type::i1(bcx.ccx) {
         bcx.zext(val, Type::i8(bcx.ccx))
diff --git a/src/librustc_trans/builder.rs b/src/librustc_trans/builder.rs
index 2b632ba6f26..6ad12a13eca 100644
--- a/src/librustc_trans/builder.rs
+++ b/src/librustc_trans/builder.rs
@@ -625,25 +625,6 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
         }
     }
 
-    // Simple wrapper around GEP that takes an array of ints and wraps them
-    // in C_i32()
-    #[inline]
-    pub fn gepi(&self, base: ValueRef, ixs: &[usize]) -> ValueRef {
-        // Small vector optimization. This should catch 100% of the cases that
-        // we care about.
-        if ixs.len() < 16 {
-            let mut small_vec = [ C_i32(self.ccx, 0); 16 ];
-            for (small_vec_e, &ix) in small_vec.iter_mut().zip(ixs) {
-                *small_vec_e = C_i32(self.ccx, ix as i32);
-            }
-            self.inbounds_gep(base, &small_vec[..ixs.len()])
-        } else {
-            let v = ixs.iter().map(|i| C_i32(self.ccx, *i as i32)).collect::<Vec<ValueRef>>();
-            self.count_insn("gepi");
-            self.inbounds_gep(base, &v)
-        }
-    }
-
     pub fn inbounds_gep(&self, ptr: ValueRef, indices: &[ValueRef]) -> ValueRef {
         self.count_insn("inboundsgep");
         unsafe {
@@ -652,8 +633,9 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
         }
     }
 
-    pub fn struct_gep(&self, ptr: ValueRef, idx: usize) -> ValueRef {
+    pub fn struct_gep(&self, ptr: ValueRef, idx: u64) -> ValueRef {
         self.count_insn("structgep");
+        assert_eq!(idx as c_uint as u64, idx);
         unsafe {
             llvm::LLVMBuildStructGEP(self.llbuilder, ptr, idx as c_uint, noname())
         }
@@ -959,16 +941,18 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
         }
     }
 
-    pub fn extract_value(&self, agg_val: ValueRef, idx: usize) -> ValueRef {
+    pub fn extract_value(&self, agg_val: ValueRef, idx: u64) -> ValueRef {
         self.count_insn("extractvalue");
+        assert_eq!(idx as c_uint as u64, idx);
         unsafe {
             llvm::LLVMBuildExtractValue(self.llbuilder, agg_val, idx as c_uint, noname())
         }
     }
 
     pub fn insert_value(&self, agg_val: ValueRef, elt: ValueRef,
-                       idx: usize) -> ValueRef {
+                       idx: u64) -> ValueRef {
         self.count_insn("insertvalue");
+        assert_eq!(idx as c_uint as u64, idx);
         unsafe {
             llvm::LLVMBuildInsertValue(self.llbuilder, agg_val, elt, idx as c_uint,
                                        noname())
diff --git a/src/librustc_trans/common.rs b/src/librustc_trans/common.rs
index 659ce0f7f9f..109c111efa9 100644
--- a/src/librustc_trans/common.rs
+++ b/src/librustc_trans/common.rs
@@ -22,7 +22,6 @@ use base;
 use builder::Builder;
 use consts;
 use declare;
-use monomorphize;
 use type_::Type;
 use value::Value;
 use rustc::traits;
@@ -68,53 +67,11 @@ pub fn type_is_immediate<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>, ty: Ty<'tcx>) -
     }
 }
 
-/// Returns Some([a, b]) if the type has a pair of fields with types a and b.
-pub fn type_pair_fields<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>, ty: Ty<'tcx>)
-                                  -> Option<[Ty<'tcx>; 2]> {
-    match ty.sty {
-        ty::TyAdt(adt, substs) => {
-            assert_eq!(adt.variants.len(), 1);
-            let fields = &adt.variants[0].fields;
-            if fields.len() != 2 {
-                return None;
-            }
-            Some([monomorphize::field_ty(ccx.tcx(), substs, &fields[0]),
-                  monomorphize::field_ty(ccx.tcx(), substs, &fields[1])])
-        }
-        ty::TyClosure(def_id, substs) => {
-            let mut tys = substs.upvar_tys(def_id, ccx.tcx());
-            tys.next().and_then(|first_ty| tys.next().and_then(|second_ty| {
-                if tys.next().is_some() {
-                    None
-                } else {
-                    Some([first_ty, second_ty])
-                }
-            }))
-        }
-        ty::TyGenerator(def_id, substs, _) => {
-            let mut tys = substs.field_tys(def_id, ccx.tcx());
-            tys.next().and_then(|first_ty| tys.next().and_then(|second_ty| {
-                if tys.next().is_some() {
-                    None
-                } else {
-                    Some([first_ty, second_ty])
-                }
-            }))
-        }
-        ty::TyTuple(tys, _) => {
-            if tys.len() != 2 {
-                return None;
-            }
-            Some([tys[0], tys[1]])
-        }
-        _ => None
-    }
-}
-
 /// Returns true if the type is represented as a pair of immediates.
 pub fn type_is_imm_pair<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>, ty: Ty<'tcx>)
                                   -> bool {
-    match *ccx.layout_of(ty) {
+    let layout = ccx.layout_of(ty);
+    match *layout {
         Layout::FatPointer { .. } => true,
         Layout::Univariant { ref variant, .. } => {
             // There must be only 2 fields.
@@ -122,12 +79,9 @@ pub fn type_is_imm_pair<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>, ty: Ty<'tcx>)
                 return false;
             }
 
-            match type_pair_fields(ccx, ty) {
-                Some([a, b]) => {
-                    type_is_immediate(ccx, a) && type_is_immediate(ccx, b)
-                }
-                None => false
-            }
+            // The two fields must be both immediates.
+            type_is_immediate(ccx, layout.field_type(ccx, 0)) &&
+            type_is_immediate(ccx, layout.field_type(ccx, 1))
         }
         _ => false
     }
@@ -356,13 +310,14 @@ pub fn C_bytes_in_context(llcx: ContextRef, bytes: &[u8]) -> ValueRef {
     }
 }
 
-pub fn const_get_elt(v: ValueRef, i: usize) -> ValueRef {
+pub fn const_get_elt(v: ValueRef, idx: u64) -> ValueRef {
     unsafe {
-        let us = &[i as c_uint];
+        assert_eq!(idx as c_uint as u64, idx);
+        let us = &[idx as c_uint];
         let r = llvm::LLVMConstExtractValue(v, us.as_ptr(), us.len() as c_uint);
 
-        debug!("const_get_elt(v={:?}, i={}, r={:?})",
-               Value(v), i, Value(r));
+        debug!("const_get_elt(v={:?}, idx={}, r={:?})",
+               Value(v), idx, Value(r));
 
         r
     }
diff --git a/src/librustc_trans/debuginfo/metadata.rs b/src/librustc_trans/debuginfo/metadata.rs
index d2e2e1bbdee..2869ddb6e22 100644
--- a/src/librustc_trans/debuginfo/metadata.rs
+++ b/src/librustc_trans/debuginfo/metadata.rs
@@ -30,10 +30,9 @@ use rustc::ty::fold::TypeVisitor;
 use rustc::ty::subst::Substs;
 use rustc::ty::util::TypeIdHasher;
 use rustc::ich::Fingerprint;
-use monomorphize;
 use common::{self, CrateContext};
 use rustc::ty::{self, AdtKind, Ty};
-use rustc::ty::layout::{self, Align, LayoutTyper, Size};
+use rustc::ty::layout::{self, Align, LayoutTyper, Size, TyLayout};
 use rustc::session::{Session, config};
 use rustc::util::nodemap::FxHashMap;
 use rustc::util::common::path2cstr;
@@ -932,7 +931,6 @@ impl<'tcx> MemberDescriptionFactory<'tcx> {
 struct StructMemberDescriptionFactory<'tcx> {
     ty: Ty<'tcx>,
     variant: &'tcx ty::VariantDef,
-    substs: &'tcx Substs<'tcx>,
     span: Span,
 }
 
@@ -960,12 +958,11 @@ impl<'tcx> StructMemberDescriptionFactory<'tcx> {
             } else {
                 f.name.to_string()
             };
-            let fty = monomorphize::field_ty(cx.tcx(), self.substs, f);
-
-            let (size, align) = cx.size_and_align_of(fty);
+            let field = layout.field(cx, i);
+            let (size, align) = field.size_and_align(cx);
             MemberDescription {
                 name,
-                type_metadata: type_metadata(cx, fty, self.span),
+                type_metadata: type_metadata(cx, field.ty, self.span),
                 offset: offsets[i],
                 size,
                 align,
@@ -983,8 +980,8 @@ fn prepare_struct_metadata<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
                                      -> RecursiveTypeDescription<'tcx> {
     let struct_name = compute_debuginfo_type_name(cx, struct_type, false);
 
-    let (struct_def_id, variant, substs) = match struct_type.sty {
-        ty::TyAdt(def, substs) => (def.did, def.struct_variant(), substs),
+    let (struct_def_id, variant) = match struct_type.sty {
+        ty::TyAdt(def, _) => (def.did, def.struct_variant()),
         _ => bug!("prepare_struct_metadata on a non-ADT")
     };
 
@@ -1004,7 +1001,6 @@ fn prepare_struct_metadata<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
         StructMDF(StructMemberDescriptionFactory {
             ty: struct_type,
             variant,
-            substs,
             span,
         })
     )
@@ -1075,20 +1071,20 @@ fn prepare_tuple_metadata<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
 //=-----------------------------------------------------------------------------
 
 struct UnionMemberDescriptionFactory<'tcx> {
+    layout: TyLayout<'tcx>,
     variant: &'tcx ty::VariantDef,
-    substs: &'tcx Substs<'tcx>,
     span: Span,
 }
 
 impl<'tcx> UnionMemberDescriptionFactory<'tcx> {
     fn create_member_descriptions<'a>(&self, cx: &CrateContext<'a, 'tcx>)
                                       -> Vec<MemberDescription> {
-        self.variant.fields.iter().map(|field| {
-            let fty = monomorphize::field_ty(cx.tcx(), self.substs, field);
-            let (size, align) = cx.size_and_align_of(fty);
+        self.variant.fields.iter().enumerate().map(|(i, f)| {
+            let field = self.layout.field(cx, i);
+            let (size, align) = field.size_and_align(cx);
             MemberDescription {
-                name: field.name.to_string(),
-                type_metadata: type_metadata(cx, fty, self.span),
+                name: f.name.to_string(),
+                type_metadata: type_metadata(cx, field.ty, self.span),
                 offset: Size::from_bytes(0),
                 size,
                 align,
@@ -1105,8 +1101,8 @@ fn prepare_union_metadata<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
                                     -> RecursiveTypeDescription<'tcx> {
     let union_name = compute_debuginfo_type_name(cx, union_type, false);
 
-    let (union_def_id, variant, substs) = match union_type.sty {
-        ty::TyAdt(def, substs) => (def.did, def.struct_variant(), substs),
+    let (union_def_id, variant) = match union_type.sty {
+        ty::TyAdt(def, _) => (def.did, def.struct_variant()),
         _ => bug!("prepare_union_metadata on a non-ADT")
     };
 
@@ -1124,8 +1120,8 @@ fn prepare_union_metadata<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
         unique_type_id,
         union_metadata_stub,
         UnionMDF(UnionMemberDescriptionFactory {
+            layout: cx.layout_of(union_type),
             variant,
-            substs,
             span,
         })
     )
@@ -1142,7 +1138,7 @@ fn prepare_union_metadata<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
 // offset of zero bytes).
 struct EnumMemberDescriptionFactory<'tcx> {
     enum_type: Ty<'tcx>,
-    type_rep: &'tcx layout::Layout,
+    type_rep: TyLayout<'tcx>,
     discriminant_type_metadata: Option<DIType>,
     containing_scope: DIScope,
     file_metadata: DIFile,
@@ -1153,11 +1149,7 @@ impl<'tcx> EnumMemberDescriptionFactory<'tcx> {
     fn create_member_descriptions<'a>(&self, cx: &CrateContext<'a, 'tcx>)
                                       -> Vec<MemberDescription> {
         let adt = &self.enum_type.ty_adt_def().unwrap();
-        let substs = match self.enum_type.sty {
-            ty::TyAdt(def, ref s) if def.adt_kind() == AdtKind::Enum => s,
-            _ => bug!("{} is not an enum", self.enum_type)
-        };
-        match *self.type_rep {
+        match *self.type_rep.layout {
             layout::General { ref variants, .. } => {
                 let discriminant_info = RegularDiscriminant(self.discriminant_type_metadata
                     .expect(""));
@@ -1169,6 +1161,7 @@ impl<'tcx> EnumMemberDescriptionFactory<'tcx> {
                             describe_enum_variant(cx,
                                                   self.enum_type,
                                                   struct_def,
+                                                  i,
                                                   &adt.variants[i],
                                                   discriminant_info,
                                                   self.containing_scope,
@@ -1200,6 +1193,7 @@ impl<'tcx> EnumMemberDescriptionFactory<'tcx> {
                         describe_enum_variant(cx,
                                               self.enum_type,
                                               variant,
+                                              0,
                                               &adt.variants[0],
                                               NoDiscriminant,
                                               self.containing_scope,
@@ -1223,19 +1217,19 @@ impl<'tcx> EnumMemberDescriptionFactory<'tcx> {
                     ]
                 }
             }
-            layout::RawNullablePointer { nndiscr: non_null_variant_index, .. } => {
+            layout::RawNullablePointer { nndiscr, .. } => {
                 // As far as debuginfo is concerned, the pointer this enum
                 // represents is still wrapped in a struct. This is to make the
                 // DWARF representation of enums uniform.
 
                 // First create a description of the artificial wrapper struct:
-                let non_null_variant = &adt.variants[non_null_variant_index as usize];
+                let non_null_variant = &adt.variants[nndiscr as usize];
                 let non_null_variant_name = non_null_variant.name.as_str();
 
                 // The llvm type and metadata of the pointer
-                let nnty = monomorphize::field_ty(cx.tcx(), &substs, &non_null_variant.fields[0]);
-                let (size, align) = cx.size_and_align_of(nnty);
-                let non_null_type_metadata = type_metadata(cx, nnty, self.span);
+                let nnfield = self.type_rep.for_variant(nndiscr as usize).field(cx, 0);
+                let (size, align) = nnfield.size_and_align(cx);
+                let non_null_type_metadata = type_metadata(cx, nnfield.ty, self.span);
 
                 // For the metadata of the wrapper struct, we need to create a
                 // MemberDescription of the struct's single field.
@@ -1264,7 +1258,7 @@ impl<'tcx> EnumMemberDescriptionFactory<'tcx> {
                 // Now we can create the metadata of the artificial struct
                 let artificial_struct_metadata =
                     composite_type_metadata(cx,
-                                            nnty,
+                                            nnfield.ty,
                                             &non_null_variant_name,
                                             unique_type_id,
                                             &[sole_struct_member_description],
@@ -1274,8 +1268,7 @@ impl<'tcx> EnumMemberDescriptionFactory<'tcx> {
 
                 // Encode the information about the null variant in the union
                 // member's name.
-                let null_variant_index = (1 - non_null_variant_index) as usize;
-                let null_variant_name = adt.variants[null_variant_index].name;
+                let null_variant_name = adt.variants[(1 - nndiscr) as usize].name;
                 let union_member_name = format!("RUST$ENCODED$ENUM${}${}",
                                                 0,
                                                 null_variant_name);
@@ -1301,6 +1294,7 @@ impl<'tcx> EnumMemberDescriptionFactory<'tcx> {
                     describe_enum_variant(cx,
                                           self.enum_type,
                                           struct_def,
+                                          nndiscr as usize,
                                           &adt.variants[nndiscr as usize],
                                           OptimizedDiscriminant,
                                           self.containing_scope,
@@ -1386,31 +1380,25 @@ enum EnumDiscriminantInfo {
 fn describe_enum_variant<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
                                    enum_type: Ty<'tcx>,
                                    struct_def: &'tcx layout::Struct,
+                                   variant_index: usize,
                                    variant: &'tcx ty::VariantDef,
                                    discriminant_info: EnumDiscriminantInfo,
                                    containing_scope: DIScope,
                                    span: Span)
                                    -> (DICompositeType, MemberDescriptionFactory<'tcx>) {
-    let substs = match enum_type.sty {
-        ty::TyAdt(def, s) if def.adt_kind() == AdtKind::Enum => s,
-        ref t @ _ => bug!("{:#?} is not an enum", t)
-    };
-
-    let maybe_discr_and_signed: Option<(layout::Integer, bool)> = match *cx.layout_of(enum_type) {
-        layout::CEnum {discr, ..} => Some((discr, true)),
-        layout::General{discr, ..} => Some((discr, false)),
-        layout::Univariant { .. }
-        | layout::RawNullablePointer { .. }
-        | layout::StructWrappedNullablePointer { .. } => None,
-        ref l @ _ => bug!("This should be unreachable. Type is {:#?} layout is {:#?}", enum_type, l)
+    let layout = cx.layout_of(enum_type);
+    let maybe_discr = match *layout {
+        layout::General { .. } => Some(layout.field_type(cx, 0)),
+        _ => None,
     };
 
-    let mut field_tys = variant.fields.iter().map(|f| {
-        monomorphize::field_ty(cx.tcx(), &substs, f)
+    let layout = layout.for_variant(variant_index);
+    let mut field_tys = (0..layout.field_count()).map(|i| {
+        layout.field_type(cx, i)
     }).collect::<Vec<_>>();
 
-    if let Some((discr, signed)) = maybe_discr_and_signed {
-        field_tys.insert(0, discr.to_ty(cx.tcx(), signed));
+    if let Some(discr) = maybe_discr {
+        field_tys.insert(0, discr);
     }
 
     // Could do some consistency checks here: size, align, field count, discr type
@@ -1560,7 +1548,7 @@ fn prepare_enum_metadata<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
         ref l @ _ => bug!("Not an enum layout: {:#?}", l)
     };
 
-    let (enum_type_size, enum_type_align) = cx.size_and_align_of(enum_type);
+    let (enum_type_size, enum_type_align) = type_rep.size_and_align(cx);
 
     let enum_name = CString::new(enum_name).unwrap();
     let unique_type_id_str = CString::new(
@@ -1588,7 +1576,7 @@ fn prepare_enum_metadata<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>,
         enum_metadata,
         EnumMDF(EnumMemberDescriptionFactory {
             enum_type,
-            type_rep: type_rep.layout,
+            type_rep,
             discriminant_type_metadata,
             containing_scope,
             file_metadata,
diff --git a/src/librustc_trans/glue.rs b/src/librustc_trans/glue.rs
index 597d8c587e9..9152a1febdf 100644
--- a/src/librustc_trans/glue.rs
+++ b/src/librustc_trans/glue.rs
@@ -19,7 +19,6 @@ use common::*;
 use llvm::{ValueRef};
 use llvm;
 use meth;
-use monomorphize;
 use rustc::ty::layout::LayoutTyper;
 use rustc::ty::{self, Ty};
 use value::Value;
@@ -38,7 +37,19 @@ pub fn size_and_align_of_dst<'a, 'tcx>(bcx: &Builder<'a, 'tcx>, t: Ty<'tcx>, inf
     }
     assert!(!info.is_null());
     match t.sty {
-        ty::TyAdt(..) | ty::TyTuple(..) => {
+        ty::TyDynamic(..) => {
+            // load size/align from vtable
+            (meth::SIZE.get_usize(bcx, info), meth::ALIGN.get_usize(bcx, info))
+        }
+        ty::TySlice(_) | ty::TyStr => {
+            let unit = t.sequence_element_type(bcx.tcx());
+            // The info in this case is the length of the str, so the size is that
+            // times the unit size.
+            let (size, align) = bcx.ccx.size_and_align_of(unit);
+            (bcx.mul(info, C_usize(bcx.ccx, size.bytes())),
+             C_usize(bcx.ccx, align.abi()))
+        }
+        _ => {
             let ccx = bcx.ccx;
             // First get the size of all statically known fields.
             // Don't use size_of because it also rounds up to alignment, which we
@@ -63,14 +74,7 @@ pub fn size_and_align_of_dst<'a, 'tcx>(bcx: &Builder<'a, 'tcx>, t: Ty<'tcx>, inf
 
             // Recurse to get the size of the dynamically sized field (must be
             // the last field).
-            let field_ty = match t.sty {
-                ty::TyAdt(def, substs) => {
-                    let last_field = def.struct_variant().fields.last().unwrap();
-                    monomorphize::field_ty(bcx.tcx(), substs, last_field)
-                },
-                ty::TyTuple(tys, _) => tys.last().unwrap(),
-                _ => unreachable!(),
-            };
+            let field_ty = layout.field_type(ccx, layout.field_count() - 1);
             let (unsized_size, unsized_align) = size_and_align_of_dst(bcx, field_ty, info);
 
             // FIXME (#26403, #27023): We should be adding padding
@@ -113,18 +117,5 @@ pub fn size_and_align_of_dst<'a, 'tcx>(bcx: &Builder<'a, 'tcx>, t: Ty<'tcx>, inf
 
             (size, align)
         }
-        ty::TyDynamic(..) => {
-            // load size/align from vtable
-            (meth::SIZE.get_usize(bcx, info), meth::ALIGN.get_usize(bcx, info))
-        }
-        ty::TySlice(_) | ty::TyStr => {
-            let unit = t.sequence_element_type(bcx.tcx());
-            // The info in this case is the length of the str, so the size is that
-            // times the unit size.
-            let (size, align) = bcx.ccx.size_and_align_of(unit);
-            (bcx.mul(info, C_usize(bcx.ccx, size.bytes())),
-             C_usize(bcx.ccx, align.abi()))
-        }
-        _ => bug!("Unexpected unsized type, found {}", t)
     }
 }
diff --git a/src/librustc_trans/intrinsic.rs b/src/librustc_trans/intrinsic.rs
index 711854e28a8..2f0e86b8cac 100644
--- a/src/librustc_trans/intrinsic.rs
+++ b/src/librustc_trans/intrinsic.rs
@@ -13,8 +13,9 @@
 use intrinsics::{self, Intrinsic};
 use llvm;
 use llvm::{ValueRef};
-use abi::{Abi, FnType};
+use abi::{self, Abi, FnType};
 use mir::lvalue::{LvalueRef, Alignment};
+use mir::operand::{OperandRef, OperandValue};
 use base::*;
 use common::*;
 use declare;
@@ -105,6 +106,7 @@ pub fn trans_intrinsic_call<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
     let name = &*tcx.item_name(def_id);
 
     let llret_ty = type_of::type_of(ccx, ret_ty);
+    let result = LvalueRef::new_sized(llresult, ret_ty, Alignment::AbiAligned);
 
     let simple = get_simple_intrinsic(ccx, name);
     let llval = match name {
@@ -238,9 +240,10 @@ pub fn trans_intrinsic_call<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
         },
         "volatile_store" => {
             let tp_ty = substs.type_at(0);
+            let dst = LvalueRef::new_sized(llargs[0], tp_ty, Alignment::AbiAligned);
             if type_is_fat_ptr(bcx.ccx, tp_ty) {
-                bcx.volatile_store(llargs[1], get_dataptr(bcx, llargs[0]));
-                bcx.volatile_store(llargs[2], get_meta(bcx, llargs[0]));
+                bcx.volatile_store(llargs[1], dst.project_field(bcx, abi::FAT_PTR_ADDR).llval);
+                bcx.volatile_store(llargs[2], dst.project_field(bcx, abi::FAT_PTR_EXTRA).llval);
             } else {
                 let val = if fn_ty.args[1].is_indirect() {
                     bcx.load(llargs[1], None)
@@ -250,7 +253,7 @@ pub fn trans_intrinsic_call<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
                     }
                     from_immediate(bcx, llargs[1])
                 };
-                let ptr = bcx.pointercast(llargs[0], val_ty(val).ptr_to());
+                let ptr = bcx.pointercast(dst.llval, val_ty(val).ptr_to());
                 let store = bcx.volatile_store(val, ptr);
                 unsafe {
                     llvm::LLVMSetAlignment(store, ccx.align_of(tp_ty).abi() as u32);
@@ -306,11 +309,14 @@ pub fn trans_intrinsic_call<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
                             let llfn = bcx.ccx.get_intrinsic(&intrinsic);
 
                             // Convert `i1` to a `bool`, and write it to the out parameter
-                            let val = bcx.call(llfn, &[llargs[0], llargs[1]], None);
-                            let result = bcx.extract_value(val, 0);
-                            let overflow = bcx.zext(bcx.extract_value(val, 1), Type::bool(ccx));
-                            bcx.store(result, bcx.struct_gep(llresult, 0), None);
-                            bcx.store(overflow, bcx.struct_gep(llresult, 1), None);
+                            let pair = bcx.call(llfn, &[llargs[0], llargs[1]], None);
+                            let val = bcx.extract_value(pair, 0);
+                            let overflow = bcx.zext(bcx.extract_value(pair, 1), Type::bool(ccx));
+
+                            let dest = result.project_field(bcx, 0);
+                            bcx.store(val, dest.llval, dest.alignment.non_abi());
+                            let dest = result.project_field(bcx, 1);
+                            bcx.store(overflow, dest.llval, dest.alignment.non_abi());
 
                             return;
                         },
@@ -373,7 +379,7 @@ pub fn trans_intrinsic_call<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
 
         "discriminant_value" => {
             let val_ty = substs.type_at(0);
-            let adt_val = LvalueRef::new_sized_ty(llargs[0], val_ty, Alignment::AbiAligned);
+            let adt_val = LvalueRef::new_sized(llargs[0], val_ty, Alignment::AbiAligned);
             match val_ty.sty {
                 ty::TyAdt(adt, ..) if adt.is_enum() => {
                     adt_val.trans_get_discr(bcx, ret_ty)
@@ -446,12 +452,15 @@ pub fn trans_intrinsic_call<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
                     let ty = substs.type_at(0);
                     if int_type_width_signed(ty, ccx).is_some() {
                         let weak = if split[1] == "cxchgweak" { llvm::True } else { llvm::False };
-                        let val = bcx.atomic_cmpxchg(llargs[0], llargs[1], llargs[2], order,
+                        let pair = bcx.atomic_cmpxchg(llargs[0], llargs[1], llargs[2], order,
                             failorder, weak);
-                        let result = bcx.extract_value(val, 0);
-                        let success = bcx.zext(bcx.extract_value(val, 1), Type::bool(bcx.ccx));
-                        bcx.store(result, bcx.struct_gep(llresult, 0), None);
-                        bcx.store(success, bcx.struct_gep(llresult, 1), None);
+                        let val = bcx.extract_value(pair, 0);
+                        let success = bcx.zext(bcx.extract_value(pair, 1), Type::bool(bcx.ccx));
+
+                        let dest = result.project_field(bcx, 0);
+                        bcx.store(val, dest.llval, dest.alignment.non_abi());
+                        let dest = result.project_field(bcx, 1);
+                        bcx.store(success, dest.llval, dest.alignment.non_abi());
                         return;
                     } else {
                         return invalid_monomorphization(ty);
@@ -589,10 +598,9 @@ pub fn trans_intrinsic_call<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
                         // destructors, and the contents are SIMD
                         // etc.
                         assert!(!bcx.ccx.shared().type_needs_drop(arg_type));
-                        let arg = LvalueRef::new_sized_ty(llarg, arg_type, Alignment::AbiAligned);
+                        let arg = LvalueRef::new_sized(llarg, arg_type, Alignment::AbiAligned);
                         (0..contents.len()).map(|i| {
-                            let (ptr, align) = arg.trans_field_ptr(bcx, i);
-                            bcx.load(ptr, align.to_align())
+                            arg.project_field(bcx, i).load(bcx).immediate()
                         }).collect()
                     }
                     intrinsics::Type::Pointer(_, Some(ref llvm_elem), _) => {
@@ -654,11 +662,9 @@ pub fn trans_intrinsic_call<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
                     assert!(!flatten);
 
                     for i in 0..elems.len() {
-                        let val = bcx.extract_value(val, i);
-                        let lval = LvalueRef::new_sized_ty(llresult, ret_ty,
-                                                           Alignment::AbiAligned);
-                        let (dest, align) = lval.trans_field_ptr(bcx, i);
-                        bcx.store(val, dest, align.to_align());
+                        let dest = result.project_field(bcx, i);
+                        let val = bcx.extract_value(val, i as u64);
+                        bcx.store(val, dest.llval, dest.alignment.non_abi());
                     }
                     return;
                 }
@@ -672,7 +678,10 @@ pub fn trans_intrinsic_call<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
             let ptr = bcx.pointercast(llresult, ty.llvm_type(ccx).ptr_to());
             bcx.store(llval, ptr, Some(ccx.align_of(ret_ty)));
         } else {
-            store_ty(bcx, llval, llresult, Alignment::AbiAligned, ret_ty);
+            OperandRef {
+                val: OperandValue::Immediate(llval),
+                ty: ret_ty
+            }.unpack_if_pair(bcx).store(bcx, result);
         }
     }
 }
@@ -1071,7 +1080,7 @@ fn generic_simd_intrinsic<'a, 'tcx>(
         let indices: Option<Vec<_>> = (0..n)
             .map(|i| {
                 let arg_idx = i;
-                let val = const_get_elt(vector, i);
+                let val = const_get_elt(vector, i as u64);
                 match const_to_opt_u128(val, true) {
                     None => {
                         emit_error!("shuffle index #{} is not a constant", arg_idx);
diff --git a/src/librustc_trans/lib.rs b/src/librustc_trans/lib.rs
index 73e03dc0691..2776125bd82 100644
--- a/src/librustc_trans/lib.rs
+++ b/src/librustc_trans/lib.rs
@@ -143,7 +143,6 @@ mod partitioning;
 mod symbol_names_test;
 mod time_graph;
 mod trans_item;
-mod tvec;
 mod type_;
 mod type_of;
 mod value;
diff --git a/src/librustc_trans/meth.rs b/src/librustc_trans/meth.rs
index a2e7eb2258f..2289adb01ea 100644
--- a/src/librustc_trans/meth.rs
+++ b/src/librustc_trans/meth.rs
@@ -21,7 +21,7 @@ use rustc::ty::layout::HasDataLayout;
 use debuginfo;
 
 #[derive(Copy, Clone, Debug)]
-pub struct VirtualIndex(usize);
+pub struct VirtualIndex(u64);
 
 pub const DESTRUCTOR: VirtualIndex = VirtualIndex(0);
 pub const SIZE: VirtualIndex = VirtualIndex(1);
@@ -29,14 +29,14 @@ pub const ALIGN: VirtualIndex = VirtualIndex(2);
 
 impl<'a, 'tcx> VirtualIndex {
     pub fn from_index(index: usize) -> Self {
-        VirtualIndex(index + 3)
+        VirtualIndex(index as u64 + 3)
     }
 
     pub fn get_fn(self, bcx: &Builder<'a, 'tcx>, llvtable: ValueRef) -> ValueRef {
         // Load the data pointer from the object.
         debug!("get_fn({:?}, {:?})", Value(llvtable), self);
 
-        let ptr = bcx.load_nonnull(bcx.gepi(llvtable, &[self.0]), None);
+        let ptr = bcx.load_nonnull(bcx.inbounds_gep(llvtable, &[C_usize(bcx.ccx, self.0)]), None);
         // Vtable loads are invariant
         bcx.set_invariant_load(ptr);
         ptr
@@ -47,7 +47,7 @@ impl<'a, 'tcx> VirtualIndex {
         debug!("get_int({:?}, {:?})", Value(llvtable), self);
 
         let llvtable = bcx.pointercast(llvtable, Type::isize(bcx.ccx).ptr_to());
-        let ptr = bcx.load(bcx.gepi(llvtable, &[self.0]), None);
+        let ptr = bcx.load(bcx.inbounds_gep(llvtable, &[C_usize(bcx.ccx, self.0)]), None);
         // Vtable loads are invariant
         bcx.set_invariant_load(ptr);
         ptr
diff --git a/src/librustc_trans/mir/block.rs b/src/librustc_trans/mir/block.rs
index abd86a5cb01..cedc78cf946 100644
--- a/src/librustc_trans/mir/block.rs
+++ b/src/librustc_trans/mir/block.rs
@@ -12,11 +12,10 @@ use llvm::{self, ValueRef, BasicBlockRef};
 use rustc::middle::lang_items;
 use rustc::middle::const_val::{ConstEvalErr, ConstInt, ErrKind};
 use rustc::ty::{self, Ty, TypeFoldable};
-use rustc::ty::layout::{self, LayoutTyper};
+use rustc::ty::layout::LayoutTyper;
 use rustc::traits;
 use rustc::mir;
 use abi::{Abi, FnType, ArgType};
-use adt;
 use base;
 use callee;
 use builder::Builder;
@@ -24,7 +23,7 @@ use common::{self, C_bool, C_str_slice, C_struct, C_u32, C_undef};
 use consts;
 use meth;
 use monomorphize;
-use type_of;
+use type_of::{self, LayoutLlvmExt};
 use type_::Type;
 
 use syntax::symbol::Symbol;
@@ -173,13 +172,8 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
                     bcx.cleanup_ret(cleanup_pad, None);
                 } else {
                     let slot = self.get_personality_slot(&bcx);
-
-                    let (lp0ptr, align) = slot.trans_field_ptr(&bcx, 0);
-                    let lp0 = bcx.load(lp0ptr, align.to_align());
-
-                    let (lp1ptr, align) = slot.trans_field_ptr(&bcx, 1);
-                    let lp1 = bcx.load(lp1ptr, align.to_align());
-
+                    let lp0 = slot.project_field(&bcx, 0).load(&bcx).immediate();
+                    let lp1 = slot.project_field(&bcx, 1).load(&bcx).immediate();
                     slot.storage_dead(&bcx);
 
                     if !bcx.sess().target.target.options.custom_unwind_resume {
@@ -240,9 +234,9 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
                     };
                     let llslot = match op.val {
                         Immediate(_) | Pair(..) => {
-                            let llscratch = bcx.alloca(ret.memory_ty(bcx.ccx), "ret", None);
-                            self.store_operand(&bcx, llscratch, None, op);
-                            llscratch
+                            let scratch = LvalueRef::alloca(&bcx, ret.layout.ty, "ret");
+                            op.store(&bcx, scratch);
+                            scratch.llval
                         }
                         Ref(llval, align) => {
                             assert_eq!(align, Alignment::AbiAligned,
@@ -257,7 +251,7 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
                 } else {
                     let op = self.trans_consume(&bcx, &mir::Lvalue::Local(mir::RETURN_POINTER));
                     if let Ref(llval, align) = op.val {
-                        base::load_ty(&bcx, llval, align, op.ty)
+                        bcx.load(llval, align.non_abi())
                     } else {
                         op.pack_if_pair(&bcx).immediate()
                     }
@@ -558,8 +552,8 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
                         ReturnDest::Nothing => {
                             (C_undef(fn_ty.ret.memory_ty(bcx.ccx).ptr_to()), &llargs[..])
                         }
-                        ReturnDest::IndirectOperand(dst, _) => (dst.llval, &llargs[..]),
-                        ReturnDest::Store(dst) => (dst, &llargs[..]),
+                        ReturnDest::IndirectOperand(dst, _) |
+                        ReturnDest::Store(dst) => (dst.llval, &llargs[..]),
                         ReturnDest::DirectOperand(_) =>
                             bug!("Cannot use direct operand with an intrinsic call")
                     };
@@ -650,21 +644,21 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
         let (mut llval, align, by_ref) = match op.val {
             Immediate(_) | Pair(..) => {
                 if arg.is_indirect() || arg.cast.is_some() {
-                    let llscratch = bcx.alloca(arg.memory_ty(bcx.ccx), "arg", None);
-                    self.store_operand(bcx, llscratch, None, op);
-                    (llscratch, Alignment::AbiAligned, true)
+                    let scratch = LvalueRef::alloca(bcx, arg.layout.ty, "arg");
+                    op.store(bcx, scratch);
+                    (scratch.llval, Alignment::AbiAligned, true)
                 } else {
                     (op.pack_if_pair(bcx).immediate(), Alignment::AbiAligned, false)
                 }
             }
-            Ref(llval, align @ Alignment::Packed) if arg.is_indirect() => {
+            Ref(llval, align @ Alignment::Packed(_)) if arg.is_indirect() => {
                 // `foo(packed.large_field)`. We can't pass the (unaligned) field directly. I
                 // think that ATM (Rust 1.16) we only pass temporaries, but we shouldn't
                 // have scary latent bugs around.
 
-                let llscratch = bcx.alloca(arg.memory_ty(bcx.ccx), "arg", None);
-                base::memcpy_ty(bcx, llscratch, llval, op.ty, align.to_align());
-                (llscratch, Alignment::AbiAligned, true)
+                let scratch = LvalueRef::alloca(bcx, arg.layout.ty, "arg");
+                base::memcpy_ty(bcx, scratch.llval, llval, op.ty, align.non_abi());
+                (scratch.llval, Alignment::AbiAligned, true)
             }
             Ref(llval, align) => (llval, align, true)
         };
@@ -672,14 +666,15 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
         if by_ref && !arg.is_indirect() {
             // Have to load the argument, maybe while casting it.
             if arg.layout.ty == bcx.tcx().types.bool {
-                // We store bools as i8 so we need to truncate to i1.
                 llval = bcx.load_range_assert(llval, 0, 2, llvm::False, None);
-                llval = bcx.trunc(llval, Type::i1(bcx.ccx));
+                // We store bools as i8 so we need to truncate to i1.
+                llval = base::to_immediate(bcx, llval, arg.layout.ty);
             } else if let Some(ty) = arg.cast {
                 llval = bcx.load(bcx.pointercast(llval, ty.llvm_type(bcx.ccx).ptr_to()),
-                                 align.min_with(Some(arg.layout.align(bcx.ccx))));
+                                 (align | Alignment::Packed(arg.layout.align(bcx.ccx)))
+                                    .non_abi());
             } else {
-                llval = bcx.load(llval, align.to_align());
+                llval = bcx.load(llval, align.non_abi());
             }
         }
 
@@ -705,38 +700,28 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
         // Handle both by-ref and immediate tuples.
         match tuple.val {
             Ref(llval, align) => {
+                let tuple_ptr = LvalueRef::new_sized(llval, tuple.ty, align);
                 for (n, &ty) in arg_types.iter().enumerate() {
-                    let ptr = LvalueRef::new_sized_ty(llval, tuple.ty, align);
-                    let (ptr, align) = ptr.trans_field_ptr(bcx, n);
-                    let val = if common::type_is_fat_ptr(bcx.ccx, ty) {
-                        let (lldata, llextra) = base::load_fat_ptr(bcx, ptr, align, ty);
-                        Pair(lldata, llextra)
+                    let field_ptr = tuple_ptr.project_field(bcx, n);
+                    let op = if common::type_is_fat_ptr(bcx.ccx, ty) {
+                        field_ptr.load(bcx)
                     } else {
                         // trans_argument will load this if it needs to
-                        Ref(ptr, align)
-                    };
-                    let op = OperandRef {
-                        val,
-                        ty,
+                        OperandRef {
+                            val: Ref(field_ptr.llval, field_ptr.alignment),
+                            ty
+                        }
                     };
                     self.trans_argument(bcx, op, llargs, fn_ty, next_idx, llfn, def);
                 }
 
             }
             Immediate(llval) => {
-                let l = bcx.ccx.layout_of(tuple.ty);
-                let v = if let layout::Univariant { ref variant, .. } = *l {
-                    variant
-                } else {
-                    bug!("Not a tuple.");
-                };
+                let layout = bcx.ccx.layout_of(tuple.ty);
                 for (n, &ty) in arg_types.iter().enumerate() {
-                    let mut elem = bcx.extract_value(
-                        llval, adt::struct_llfields_index(v, n));
+                    let mut elem = bcx.extract_value(llval, layout.llvm_field_index(n));
                     // Truncate bools to i1, if needed
-                    if ty.is_bool() && common::val_ty(elem) != Type::i1(bcx.ccx) {
-                        elem = bcx.trunc(elem, Type::i1(bcx.ccx));
-                    }
+                    elem = base::to_immediate(bcx, elem, ty);
                     // If the tuple is immediate, the elements are as well
                     let op = OperandRef {
                         val: Immediate(elem),
@@ -748,11 +733,7 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
             Pair(a, b) => {
                 let elems = [a, b];
                 for (n, &ty) in arg_types.iter().enumerate() {
-                    let mut elem = elems[n];
-                    // Truncate bools to i1, if needed
-                    if ty.is_bool() && common::val_ty(elem) != Type::i1(bcx.ccx) {
-                        elem = bcx.trunc(elem, Type::i1(bcx.ccx));
-                    }
+                    let elem = base::to_immediate(bcx, elems[n], ty);
                     // Pair is always made up of immediates
                     let op = OperandRef {
                         val: Immediate(elem),
@@ -809,10 +790,10 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
 
         let slot = self.get_personality_slot(&bcx);
         slot.storage_live(&bcx);
-        self.store_operand(&bcx, slot.llval, None, OperandRef {
+        OperandRef {
             val: Pair(bcx.extract_value(lp, 0), bcx.extract_value(lp, 1)),
             ty: slot.ty.to_ty(ccx.tcx())
-        });
+        }.store(&bcx, slot);
 
         bcx.br(target_bb);
         bcx.llbb()
@@ -888,7 +869,7 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
                     llargs.push(dest.llval);
                     ReturnDest::Nothing
                 },
-                Alignment::Packed => {
+                Alignment::Packed(_) => {
                     // Currently, MIR code generation does not create calls
                     // that store directly to fields of packed structs (in
                     // fact, the calls it creates write only to temps),
@@ -899,7 +880,7 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
                 }
             }
         } else {
-            ReturnDest::Store(dest.llval)
+            ReturnDest::Store(dest)
         }
     }
 
@@ -908,14 +889,14 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
                        dst: &mir::Lvalue<'tcx>) {
         if let mir::Lvalue::Local(index) = *dst {
             match self.locals[index] {
-                LocalRef::Lvalue(lvalue) => self.trans_transmute_into(bcx, src, &lvalue),
+                LocalRef::Lvalue(lvalue) => self.trans_transmute_into(bcx, src, lvalue),
                 LocalRef::Operand(None) => {
                     let lvalue_ty = self.monomorphized_lvalue_ty(dst);
                     assert!(!lvalue_ty.has_erasable_regions());
                     let lvalue = LvalueRef::alloca(bcx, lvalue_ty, "transmute_temp");
                     lvalue.storage_live(bcx);
-                    self.trans_transmute_into(bcx, src, &lvalue);
-                    let op = self.trans_load(bcx, lvalue.llval, lvalue.alignment, lvalue_ty);
+                    self.trans_transmute_into(bcx, src, lvalue);
+                    let op = lvalue.load(bcx);
                     lvalue.storage_dead(bcx);
                     self.locals[index] = LocalRef::Operand(Some(op));
                 }
@@ -927,20 +908,21 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
             }
         } else {
             let dst = self.trans_lvalue(bcx, dst);
-            self.trans_transmute_into(bcx, src, &dst);
+            self.trans_transmute_into(bcx, src, dst);
         }
     }
 
     fn trans_transmute_into(&mut self, bcx: &Builder<'a, 'tcx>,
                             src: &mir::Operand<'tcx>,
-                            dst: &LvalueRef<'tcx>) {
+                            dst: LvalueRef<'tcx>) {
         let val = self.trans_operand(bcx, src);
         let llty = type_of::type_of(bcx.ccx, val.ty);
         let cast_ptr = bcx.pointercast(dst.llval, llty.ptr_to());
         let in_type = val.ty;
         let out_type = dst.ty.to_ty(bcx.tcx());
         let align = bcx.ccx.align_of(in_type).min(bcx.ccx.align_of(out_type));
-        self.store_operand(bcx, cast_ptr, Some(align), val);
+        val.store(bcx,
+            LvalueRef::new_sized(cast_ptr, val.ty, Alignment::Packed(align)));
     }
 
 
@@ -956,7 +938,7 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
             Nothing => (),
             Store(dst) => ret_ty.store(bcx, op.immediate(), dst),
             IndirectOperand(tmp, index) => {
-                let op = self.trans_load(bcx, tmp.llval, Alignment::AbiAligned, op.ty);
+                let op = tmp.load(bcx);
                 tmp.storage_dead(bcx);
                 self.locals[index] = LocalRef::Operand(Some(op));
             }
@@ -965,8 +947,8 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
                 let op = if ret_ty.cast.is_some() {
                     let tmp = LvalueRef::alloca(bcx, op.ty, "tmp_ret");
                     tmp.storage_live(bcx);
-                    ret_ty.store(bcx, op.immediate(), tmp.llval);
-                    let op = self.trans_load(bcx, tmp.llval, tmp.alignment, op.ty);
+                    ret_ty.store(bcx, op.immediate(), tmp);
+                    let op = tmp.load(bcx);
                     tmp.storage_dead(bcx);
                     op
                 } else {
@@ -982,7 +964,7 @@ enum ReturnDest<'tcx> {
     // Do nothing, the return value is indirect or ignored
     Nothing,
     // Store the return value to the pointer
-    Store(ValueRef),
+    Store(LvalueRef<'tcx>),
     // Stores an indirect return value to an operand local lvalue
     IndirectOperand(LvalueRef<'tcx>, mir::Local),
     // Stores a direct return value to an operand local lvalue
diff --git a/src/librustc_trans/mir/constant.rs b/src/librustc_trans/mir/constant.rs
index d4289363ecf..c2bc0684c62 100644
--- a/src/librustc_trans/mir/constant.rs
+++ b/src/librustc_trans/mir/constant.rs
@@ -32,7 +32,7 @@ use common::{C_array, C_bool, C_bytes, C_int, C_uint, C_big_integral, C_u32, C_u
 use common::{C_null, C_struct, C_str_slice, C_undef, C_usize, C_vector};
 use common::const_to_opt_u128;
 use consts;
-use type_of;
+use type_of::{self, LayoutLlvmExt};
 use type_::Type;
 use value::Value;
 
@@ -117,14 +117,7 @@ impl<'a, 'tcx> Const<'tcx> {
     }
 
     fn get_field(&self, ccx: &CrateContext<'a, 'tcx>, i: usize) -> ValueRef {
-        let layout = ccx.layout_of(self.ty);
-        let ix = if let layout::Univariant { ref variant, .. } = *layout {
-            adt::struct_llfields_index(variant, i)
-        } else {
-            i
-        };
-
-        const_get_elt(self.llval, ix)
+        const_get_elt(self.llval, ccx.layout_of(self.ty).llvm_field_index(i))
     }
 
     fn get_pair(&self, ccx: &CrateContext<'a, 'tcx>) -> (ValueRef, ValueRef) {
@@ -494,7 +487,7 @@ impl<'a, 'tcx> MirConstContext<'a, 'tcx> {
                         // Produce an undef instead of a LLVM assertion on OOB.
                         let len = common::const_to_uint(tr_base.len(self.ccx));
                         let llelem = if iv < len as u128 {
-                            const_get_elt(base.llval, iv as usize)
+                            const_get_elt(base.llval, iv as u64)
                         } else {
                             C_undef(type_of::type_of(self.ccx, projected_ty))
                         };
diff --git a/src/librustc_trans/mir/lvalue.rs b/src/librustc_trans/mir/lvalue.rs
index a0cab01b007..168f2e8c056 100644
--- a/src/librustc_trans/mir/lvalue.rs
+++ b/src/librustc_trans/mir/lvalue.rs
@@ -10,28 +10,31 @@
 
 use llvm::{self, ValueRef};
 use rustc::ty::{self, Ty, TypeFoldable};
-use rustc::ty::layout::{self, Align, LayoutTyper};
+use rustc::ty::layout::{self, Align, Layout, LayoutTyper};
 use rustc::mir;
 use rustc::mir::tcx::LvalueTy;
 use rustc_data_structures::indexed_vec::Idx;
+use abi;
 use adt;
 use base;
 use builder::Builder;
-use common::{self, CrateContext, C_usize, C_u8, C_i32, C_int, C_null, val_ty};
+use common::{self, CrateContext, C_usize, C_u8, C_u32, C_int, C_null, val_ty};
 use consts;
-use type_of;
+use type_of::{self, LayoutLlvmExt};
 use type_::Type;
 use value::Value;
 use glue;
 
+use std::iter;
 use std::ptr;
 use std::ops;
 
 use super::{MirContext, LocalRef};
+use super::operand::{OperandRef, OperandValue};
 
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
 pub enum Alignment {
-    Packed,
+    Packed(Align),
     AbiAligned,
 }
 
@@ -40,31 +43,41 @@ impl ops::BitOr for Alignment {
 
     fn bitor(self, rhs: Self) -> Self {
         match (self, rhs) {
-            (Alignment::Packed, _) => Alignment::Packed,
-            (Alignment::AbiAligned, a) => a,
+            (Alignment::Packed(a), Alignment::Packed(b)) => {
+                Alignment::Packed(a.min(b))
+            }
+            (Alignment::Packed(x), _) | (_, Alignment::Packed(x)) => {
+                Alignment::Packed(x)
+            }
+            (Alignment::AbiAligned, Alignment::AbiAligned) => {
+                Alignment::AbiAligned
+            }
         }
     }
 }
 
-impl Alignment {
-    pub fn from_packed(packed: bool) -> Self {
+impl<'a> From<&'a Layout> for Alignment {
+    fn from(layout: &Layout) -> Self {
+        let (packed, align) = match *layout {
+            Layout::UntaggedUnion { ref variants } => (variants.packed, variants.align),
+            Layout::Univariant { ref variant, .. } => (variant.packed, variant.align),
+            _ => return Alignment::AbiAligned
+        };
         if packed {
-            Alignment::Packed
+            Alignment::Packed(align)
         } else {
             Alignment::AbiAligned
         }
     }
+}
 
-    pub fn to_align(self) -> Option<Align> {
+impl Alignment {
+    pub fn non_abi(self) -> Option<Align> {
         match self {
-            Alignment::Packed => Some(Align::from_bytes(1, 1).unwrap()),
+            Alignment::Packed(x) => Some(x),
             Alignment::AbiAligned => None,
         }
     }
-
-    pub fn min_with(self, align: Option<Align>) -> Option<Align> {
-        self.to_align().or(align)
-    }
 }
 
 fn target_sets_discr_via_memset<'a, 'tcx>(bcx: &Builder<'a, 'tcx>) -> bool {
@@ -87,13 +100,8 @@ pub struct LvalueRef<'tcx> {
 }
 
 impl<'a, 'tcx> LvalueRef<'tcx> {
-    pub fn new_sized(llval: ValueRef, lvalue_ty: LvalueTy<'tcx>,
-                     alignment: Alignment) -> LvalueRef<'tcx> {
-        LvalueRef { llval: llval, llextra: ptr::null_mut(), ty: lvalue_ty, alignment: alignment }
-    }
-
-    pub fn new_sized_ty(llval: ValueRef, ty: Ty<'tcx>, alignment: Alignment) -> LvalueRef<'tcx> {
-        LvalueRef::new_sized(llval, LvalueTy::from_ty(ty), alignment)
+    pub fn new_sized(llval: ValueRef, ty: Ty<'tcx>, alignment: Alignment) -> LvalueRef<'tcx> {
+        LvalueRef { llval, llextra: ptr::null_mut(), ty: LvalueTy::from_ty(ty), alignment }
     }
 
     pub fn alloca(bcx: &Builder<'a, 'tcx>, ty: Ty<'tcx>, name: &str) -> LvalueRef<'tcx> {
@@ -101,7 +109,7 @@ impl<'a, 'tcx> LvalueRef<'tcx> {
         let tmp = bcx.alloca(
             type_of::type_of(bcx.ccx, ty), name, bcx.ccx.over_align_of(ty));
         assert!(!ty.has_param_types());
-        Self::new_sized_ty(tmp, ty, Alignment::AbiAligned)
+        Self::new_sized(tmp, ty, Alignment::AbiAligned)
     }
 
     pub fn len(&self, ccx: &CrateContext<'a, 'tcx>) -> ValueRef {
@@ -122,8 +130,74 @@ impl<'a, 'tcx> LvalueRef<'tcx> {
         !self.llextra.is_null()
     }
 
+    pub fn load(&self, bcx: &Builder<'a, 'tcx>) -> OperandRef<'tcx> {
+        debug!("LvalueRef::load: {:?}", self);
+
+        assert!(!self.has_extra());
+
+        let ty = self.ty.to_ty(bcx.tcx());
+
+        if common::type_is_zero_size(bcx.ccx, ty) {
+            return OperandRef::new_zst(bcx.ccx, ty);
+        }
+
+        let val = if common::type_is_fat_ptr(bcx.ccx, ty) {
+            let data = self.project_field(bcx, abi::FAT_PTR_ADDR);
+            let lldata = if ty.is_region_ptr() || ty.is_box() {
+                bcx.load_nonnull(data.llval, data.alignment.non_abi())
+            } else {
+                bcx.load(data.llval, data.alignment.non_abi())
+            };
+
+            let extra = self.project_field(bcx, abi::FAT_PTR_EXTRA);
+            let meta_ty = val_ty(extra.llval);
+            // If the 'extra' field is a pointer, it's a vtable, so use load_nonnull
+            // instead
+            let llextra = if meta_ty.element_type().kind() == llvm::TypeKind::Pointer {
+                bcx.load_nonnull(extra.llval, extra.alignment.non_abi())
+            } else {
+                bcx.load(extra.llval, extra.alignment.non_abi())
+            };
+
+            OperandValue::Pair(lldata, llextra)
+        } else if common::type_is_imm_pair(bcx.ccx, ty) {
+            OperandValue::Pair(
+                self.project_field(bcx, 0).load(bcx).pack_if_pair(bcx).immediate(),
+                self.project_field(bcx, 1).load(bcx).pack_if_pair(bcx).immediate())
+        } else if common::type_is_immediate(bcx.ccx, ty) {
+            let mut const_llval = ptr::null_mut();
+            unsafe {
+                let global = llvm::LLVMIsAGlobalVariable(self.llval);
+                if !global.is_null() && llvm::LLVMIsGlobalConstant(global) == llvm::True {
+                    const_llval = llvm::LLVMGetInitializer(global);
+                }
+            }
+
+            let llval = if !const_llval.is_null() {
+                const_llval
+            } else if ty.is_bool() {
+                bcx.load_range_assert(self.llval, 0, 2, llvm::False,
+                    self.alignment.non_abi())
+            } else if ty.is_char() {
+                // a char is a Unicode codepoint, and so takes values from 0
+                // to 0x10FFFF inclusive only.
+                bcx.load_range_assert(self.llval, 0, 0x10FFFF + 1, llvm::False,
+                    self.alignment.non_abi())
+            } else if ty.is_region_ptr() || ty.is_box() || ty.is_fn() {
+                bcx.load_nonnull(self.llval, self.alignment.non_abi())
+            } else {
+                bcx.load(self.llval, self.alignment.non_abi())
+            };
+            OperandValue::Immediate(base::to_immediate(bcx, llval, ty))
+        } else {
+            OperandValue::Ref(self.llval, self.alignment)
+        };
+
+        OperandRef { val, ty }
+    }
+
     /// Access a field, at a point when the value's case is known.
-    pub fn trans_field_ptr(self, bcx: &Builder<'a, 'tcx>, ix: usize) -> (ValueRef, Alignment) {
+    pub fn project_field(self, bcx: &Builder<'a, 'tcx>, ix: usize) -> LvalueRef<'tcx> {
         let ccx = bcx.ccx;
         let mut l = ccx.layout_of(self.ty.to_ty(bcx.tcx()));
         match self.ty {
@@ -132,16 +206,16 @@ impl<'a, 'tcx> LvalueRef<'tcx> {
                 l = l.for_variant(variant_index)
             }
         }
-        let fty = l.field(ccx, ix).ty;
-        let mut ix = ix;
-        let st = match *l {
-            layout::Vector { .. } => {
-                return (bcx.struct_gep(self.llval, ix), self.alignment);
-            }
-            layout::UntaggedUnion { ref variants } => {
+        let fty = l.field_type(ccx, ix);
+
+        let alignment = self.alignment | Alignment::from(&*l);
+
+        // Handle all the non-aggregate cases first.
+        match *l {
+            layout::UntaggedUnion { .. } => {
                 let ty = type_of::in_memory_type_of(ccx, fty);
-                return (bcx.pointercast(self.llval, ty.ptr_to()),
-                    self.alignment | Alignment::from_packed(variants.packed));
+                return LvalueRef::new_sized(
+                    bcx.pointercast(self.llval, ty.ptr_to()), fty, alignment);
             }
             layout::RawNullablePointer { nndiscr, .. } |
             layout::StructWrappedNullablePointer { nndiscr,  .. }
@@ -150,58 +224,66 @@ impl<'a, 'tcx> LvalueRef<'tcx> {
                 // (e.d., Result of Either with (), as one side.)
                 let ty = type_of::type_of(ccx, fty);
                 assert_eq!(ccx.size_of(fty).bytes(), 0);
-                return (bcx.pointercast(self.llval, ty.ptr_to()), Alignment::Packed);
+                return LvalueRef::new_sized(
+                    bcx.pointercast(self.llval, ty.ptr_to()), fty,
+                    Alignment::Packed(Align::from_bytes(1, 1).unwrap()));
             }
             layout::RawNullablePointer { .. } => {
                 let ty = type_of::type_of(ccx, fty);
-                return (bcx.pointercast(self.llval, ty.ptr_to()), self.alignment);
+                return LvalueRef::new_sized(
+                    bcx.pointercast(self.llval, ty.ptr_to()), fty, alignment);
             }
-            layout::Univariant { ref variant, .. } => variant,
-            layout::StructWrappedNullablePointer { ref nonnull, .. } => nonnull,
-            layout::General { ref variants, .. } => {
+            _ => {}
+        }
+
+        // Adjust the index to account for enum discriminants in variants.
+        let mut ix = ix;
+        if let layout::General { .. } = *l {
+            if l.variant_index.is_some() {
                 ix += 1;
-                &variants[l.variant_index.unwrap()]
             }
-            _ => bug!("element access in type without elements: {} represented as {:#?}", l.ty, l)
-        };
+        }
 
-        let alignment = self.alignment | Alignment::from_packed(st.packed);
+        let simple = || {
+            LvalueRef {
+                llval: bcx.struct_gep(self.llval, l.llvm_field_index(ix)),
+                llextra: if !ccx.shared().type_has_metadata(fty) {
+                    ptr::null_mut()
+                } else {
+                    self.llextra
+                },
+                ty: LvalueTy::from_ty(fty),
+                alignment,
+            }
+        };
 
-        let ptr_val = if let layout::General { discr, .. } = *l {
-            let variant_ty = Type::struct_(ccx,
-                &adt::struct_llfields(ccx, l.ty, l.variant_index.unwrap(), st,
-                                      Some(discr.to_ty(bcx.tcx(), false))), st.packed);
-            bcx.pointercast(self.llval, variant_ty.ptr_to())
-        } else {
-            self.llval
+        // Check whether the variant being used is packed, if applicable.
+        let is_packed = match (&*l, l.variant_index) {
+            (&layout::Univariant { ref variant, .. }, _) => variant.packed,
+            (&layout::StructWrappedNullablePointer { ref nonnull, .. }, _) => nonnull.packed,
+            (&layout::General { ref variants, .. }, Some(v)) => variants[v].packed,
+            _ => return simple()
         };
 
         // Simple case - we can just GEP the field
-        //   * First field - Always aligned properly
         //   * Packed struct - There is no alignment padding
         //   * Field is sized - pointer is properly aligned already
-        if st.offsets[ix] == layout::Size::from_bytes(0) || st.packed ||
-            ccx.shared().type_is_sized(fty)
-        {
-            return (bcx.struct_gep(
-                    ptr_val, adt::struct_llfields_index(st, ix)), alignment);
+        if is_packed || ccx.shared().type_is_sized(fty) {
+            return simple();
         }
 
         // If the type of the last field is [T], str or a foreign type, then we don't need to do
         // any adjusments
         match fty.sty {
-            ty::TySlice(..) | ty::TyStr | ty::TyForeign(..) => {
-                return (bcx.struct_gep(
-                        ptr_val, adt::struct_llfields_index(st, ix)), alignment);
-            }
+            ty::TySlice(..) | ty::TyStr | ty::TyForeign(..) => return simple(),
             _ => ()
         }
 
         // There's no metadata available, log the case and just do the GEP.
         if !self.has_extra() {
             debug!("Unsized field `{}`, of `{:?}` has no metadata for adjustment",
-                ix, Value(ptr_val));
-            return (bcx.struct_gep(ptr_val, adt::struct_llfields_index(st, ix)), alignment);
+                ix, Value(self.llval));
+            return simple();
         }
 
         // We need to get the pointer manually now.
@@ -222,7 +304,7 @@ impl<'a, 'tcx> LvalueRef<'tcx> {
         let meta = self.llextra;
 
 
-        let offset = st.offsets[ix].bytes();
+        let offset = l.field_offset(ccx, ix).bytes();
         let unaligned_offset = C_usize(ccx, offset);
 
         // Get the alignment of the field
@@ -241,21 +323,29 @@ impl<'a, 'tcx> LvalueRef<'tcx> {
         debug!("struct_field_ptr: DST field offset: {:?}", Value(offset));
 
         // Cast and adjust pointer
-        let byte_ptr = bcx.pointercast(ptr_val, Type::i8p(ccx));
+        let byte_ptr = bcx.pointercast(self.llval, Type::i8p(ccx));
         let byte_ptr = bcx.gep(byte_ptr, &[offset]);
 
         // Finally, cast back to the type expected
         let ll_fty = type_of::in_memory_type_of(ccx, fty);
         debug!("struct_field_ptr: Field type is {:?}", ll_fty);
-        (bcx.pointercast(byte_ptr, ll_fty.ptr_to()), alignment)
+
+        LvalueRef {
+            llval: bcx.pointercast(byte_ptr, ll_fty.ptr_to()),
+            llextra: self.llextra,
+            ty: LvalueTy::from_ty(fty),
+            alignment,
+        }
     }
 
     // Double index to account for padding (FieldPath already uses `Struct::memory_index`)
     fn gepi_struct_llfields_path(self, bcx: &Builder, discrfield: &layout::FieldPath) -> ValueRef {
-        let path = discrfield.iter().map(|&i| {
-            adt::memory_index_to_gep(i as usize)
-        }).collect::<Vec<_>>();
-        bcx.gepi(self.llval, &path)
+        let path = iter::once(C_u32(bcx.ccx, 0)).chain(discrfield[1..].iter().map(|&i| {
+            let i = adt::memory_index_to_gep(i as u64);
+            assert_eq!(i as u32 as u64, i);
+            C_u32(bcx.ccx, i as u32)
+        })).collect::<Vec<_>>();
+        bcx.inbounds_gep(self.llval, &path)
     }
 
     /// Helper for cases where the discriminant is simply loaded.
@@ -274,12 +364,12 @@ impl<'a, 'tcx> LvalueRef<'tcx> {
             // rejected by the LLVM verifier (it would mean either an
             // empty set, which is impossible, or the entire range of the
             // type, which is pointless).
-            bcx.load(ptr, self.alignment.to_align())
+            bcx.load(ptr, self.alignment.non_abi())
         } else {
             // llvm::ConstantRange can deal with ranges that wrap around,
             // so an overflow on (max + 1) is fine.
             bcx.load_range_assert(ptr, min, max.wrapping_add(1), /* signed: */ llvm::True,
-                                  self.alignment.to_align())
+                                  self.alignment.non_abi())
         }
     }
 
@@ -292,18 +382,18 @@ impl<'a, 'tcx> LvalueRef<'tcx> {
                 self.load_discr(bcx, discr, self.llval, min, max)
             }
             layout::General { discr, ref variants, .. } => {
-                let ptr = bcx.struct_gep(self.llval, 0);
-                self.load_discr(bcx, discr, ptr, 0, variants.len() as u64 - 1)
+                let ptr = self.project_field(bcx, 0);
+                self.load_discr(bcx, discr, ptr.llval, 0, variants.len() as u64 - 1)
             }
             layout::Univariant { .. } | layout::UntaggedUnion { .. } => C_u8(bcx.ccx, 0),
             layout::RawNullablePointer { nndiscr, .. } => {
                 let cmp = if nndiscr == 0 { llvm::IntEQ } else { llvm::IntNE };
-                let discr = bcx.load(self.llval, self.alignment.to_align());
+                let discr = bcx.load(self.llval, self.alignment.non_abi());
                 bcx.icmp(cmp, discr, C_null(val_ty(discr)))
             }
             layout::StructWrappedNullablePointer { nndiscr, ref discrfield, .. } => {
                 let llptrptr = self.gepi_struct_llfields_path(bcx, discrfield);
-                let llptr = bcx.load(llptrptr, self.alignment.to_align());
+                let llptr = bcx.load(llptrptr, self.alignment.non_abi());
                 let cmp = if nndiscr == 0 { llvm::IntEQ } else { llvm::IntNE };
                 bcx.icmp(cmp, llptr, C_null(val_ty(llptr)))
             },
@@ -324,11 +414,12 @@ impl<'a, 'tcx> LvalueRef<'tcx> {
             layout::CEnum { discr, min, max, .. } => {
                 adt::assert_discr_in_range(min, max, to);
                 bcx.store(C_int(Type::from_integer(bcx.ccx, discr), to as i64),
-                    self.llval, self.alignment.to_align());
+                    self.llval, self.alignment.non_abi());
             }
             layout::General { discr, .. } => {
+                let ptr = self.project_field(bcx, 0);
                 bcx.store(C_int(Type::from_integer(bcx.ccx, discr), to as i64),
-                    bcx.struct_gep(self.llval, 0), self.alignment.to_align());
+                    ptr.llval, ptr.alignment.non_abi());
             }
             layout::Univariant { .. }
             | layout::UntaggedUnion { .. }
@@ -338,7 +429,7 @@ impl<'a, 'tcx> LvalueRef<'tcx> {
             layout::RawNullablePointer { nndiscr, .. } => {
                 if to != nndiscr {
                     let llptrty = val_ty(self.llval).element_type();
-                    bcx.store(C_null(llptrty), self.llval, self.alignment.to_align());
+                    bcx.store(C_null(llptrty), self.llval, self.alignment.non_abi());
                 }
             }
             layout::StructWrappedNullablePointer { nndiscr, ref discrfield, ref nonnull, .. } => {
@@ -350,12 +441,12 @@ impl<'a, 'tcx> LvalueRef<'tcx> {
                         let llptr = bcx.pointercast(self.llval, Type::i8(bcx.ccx).ptr_to());
                         let fill_byte = C_u8(bcx.ccx, 0);
                         let size = C_usize(bcx.ccx, nonnull.stride().bytes());
-                        let align = C_i32(bcx.ccx, nonnull.align.abi() as i32);
+                        let align = C_u32(bcx.ccx, nonnull.align.abi() as u32);
                         base::call_memset(bcx, llptr, fill_byte, size, align, false);
                     } else {
                         let llptrptr = self.gepi_struct_llfields_path(bcx, discrfield);
                         let llptrty = val_ty(llptrptr).element_type();
-                        bcx.store(C_null(llptrty), llptrptr, self.alignment.to_align());
+                        bcx.store(C_null(llptrty), llptrptr, self.alignment.non_abi());
                     }
                 }
             }
@@ -363,13 +454,47 @@ impl<'a, 'tcx> LvalueRef<'tcx> {
         }
     }
 
-    pub fn project_index(&self, bcx: &Builder<'a, 'tcx>, llindex: ValueRef) -> ValueRef {
-        if let ty::TySlice(_) = self.ty.to_ty(bcx.tcx()).sty {
-            // Slices already point to the array element type.
-            bcx.inbounds_gep(self.llval, &[llindex])
+    pub fn project_index(&self, bcx: &Builder<'a, 'tcx>, llindex: ValueRef)
+                         -> LvalueRef<'tcx> {
+        let ty = self.ty.to_ty(bcx.tcx());
+        let (ptr, elem_ty) = match ty.sty {
+            ty::TySlice(ty) => {
+                // Slices already point to the array element type.
+                (bcx.inbounds_gep(self.llval, &[llindex]), ty)
+            }
+            ty::TyArray(ty, _) => {
+                let zero = common::C_usize(bcx.ccx, 0);
+                (bcx.inbounds_gep(self.llval, &[zero, llindex]), ty)
+            }
+            _ => bug!("unexpected type `{}` in LvalueRef::project_index", ty)
+        };
+        LvalueRef::new_sized(ptr, elem_ty, self.alignment)
+    }
+
+    pub fn project_downcast(&self, bcx: &Builder<'a, 'tcx>, variant_index: usize)
+                            -> LvalueRef<'tcx> {
+        let ty = self.ty.to_ty(bcx.tcx());
+        if let ty::TyAdt(adt_def, substs) = ty.sty {
+            let mut downcast = *self;
+            downcast.ty = LvalueTy::Downcast {
+                adt_def,
+                substs,
+                variant_index,
+            };
+
+            // If this is an enum, cast to the appropriate variant struct type.
+            let layout = bcx.ccx.layout_of(ty).for_variant(variant_index);
+            if let layout::General { discr, ref variants, .. } = *layout {
+                let st = &variants[variant_index];
+                let variant_ty = Type::struct_(bcx.ccx,
+                    &adt::struct_llfields(bcx.ccx, layout, st,
+                        Some(discr.to_ty(bcx.tcx(), false))), st.packed);
+                downcast.llval = bcx.pointercast(downcast.llval, variant_ty.ptr_to());
+            }
+
+            downcast
         } else {
-            let zero = common::C_usize(bcx.ccx, 0);
-            bcx.inbounds_gep(self.llval, &[zero, llindex])
+            bug!("unexpected type `{}` in LvalueRef::project_downcast", ty)
         }
     }
 
@@ -407,7 +532,7 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
             mir::Lvalue::Local(_) => bug!(), // handled above
             mir::Lvalue::Static(box mir::Static { def_id, ty }) => {
                 LvalueRef::new_sized(consts::get_static(ccx, def_id),
-                                     LvalueTy::from_ty(self.monomorphize(&ty)),
+                                     self.monomorphize(&ty),
                                      Alignment::AbiAligned)
             },
             mir::Lvalue::Projection(box mir::Projection {
@@ -419,33 +544,23 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
             }
             mir::Lvalue::Projection(ref projection) => {
                 let tr_base = self.trans_lvalue(bcx, &projection.base);
-                let projected_ty = tr_base.ty.projection_ty(tcx, &projection.elem);
-                let projected_ty = self.monomorphize(&projected_ty);
-                let align = tr_base.alignment;
 
-                let ((llprojected, align), llextra) = match projection.elem {
+                match projection.elem {
                     mir::ProjectionElem::Deref => bug!(),
                     mir::ProjectionElem::Field(ref field, _) => {
-                        let has_metadata = self.ccx.shared()
-                            .type_has_metadata(projected_ty.to_ty(tcx));
-                        let llextra = if !has_metadata {
-                            ptr::null_mut()
-                        } else {
-                            tr_base.llextra
-                        };
-                        (tr_base.trans_field_ptr(bcx, field.index()), llextra)
+                        tr_base.project_field(bcx, field.index())
                     }
                     mir::ProjectionElem::Index(index) => {
                         let index = &mir::Operand::Consume(mir::Lvalue::Local(index));
                         let index = self.trans_operand(bcx, index);
                         let llindex = index.immediate();
-                        ((tr_base.project_index(bcx, llindex), align), ptr::null_mut())
+                        tr_base.project_index(bcx, llindex)
                     }
                     mir::ProjectionElem::ConstantIndex { offset,
                                                          from_end: false,
                                                          min_length: _ } => {
                         let lloffset = C_usize(bcx.ccx, offset as u64);
-                        ((tr_base.project_index(bcx, lloffset), align), ptr::null_mut())
+                        tr_base.project_index(bcx, lloffset)
                     }
                     mir::ProjectionElem::ConstantIndex { offset,
                                                          from_end: true,
@@ -453,39 +568,34 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
                         let lloffset = C_usize(bcx.ccx, offset as u64);
                         let lllen = tr_base.len(bcx.ccx);
                         let llindex = bcx.sub(lllen, lloffset);
-                        ((tr_base.project_index(bcx, llindex), align), ptr::null_mut())
+                        tr_base.project_index(bcx, llindex)
                     }
                     mir::ProjectionElem::Subslice { from, to } => {
-                        let llbase = tr_base.project_index(bcx, C_usize(bcx.ccx, from as u64));
+                        let mut subslice = tr_base.project_index(bcx,
+                            C_usize(bcx.ccx, from as u64));
+                        subslice.ty = tr_base.ty.projection_ty(tcx, &projection.elem);
+                        subslice.ty = self.monomorphize(&subslice.ty);
 
-                        let base_ty = tr_base.ty.to_ty(bcx.tcx());
-                        match base_ty.sty {
+                        match subslice.ty.to_ty(tcx).sty {
                             ty::TyArray(..) => {
                                 // must cast the lvalue pointer type to the new
                                 // array type (*[%_; new_len]).
-                                let base_ty = self.monomorphized_lvalue_ty(lvalue);
-                                let llbasety = type_of::type_of(bcx.ccx, base_ty).ptr_to();
-                                let llbase = bcx.pointercast(llbase, llbasety);
-                                ((llbase, align), ptr::null_mut())
+                                subslice.llval = bcx.pointercast(subslice.llval,
+                                    type_of::type_of(bcx.ccx, subslice.ty.to_ty(tcx)).ptr_to())
                             }
                             ty::TySlice(..) => {
-                                assert!(tr_base.llextra != ptr::null_mut());
-                                let lllen = bcx.sub(tr_base.llextra,
-                                                    C_usize(bcx.ccx, (from as u64)+(to as u64)));
-                                ((llbase, align), lllen)
+                                assert!(tr_base.has_extra());
+                                subslice.llextra = bcx.sub(tr_base.llextra,
+                                    C_usize(bcx.ccx, (from as u64) + (to as u64)));
                             }
-                            _ => bug!("unexpected type {:?} in Subslice", base_ty)
+                            _ => bug!("unexpected type {:?} in Subslice", subslice.ty)
                         }
+
+                        subslice
                     }
-                    mir::ProjectionElem::Downcast(..) => {
-                        ((tr_base.llval, align), tr_base.llextra)
+                    mir::ProjectionElem::Downcast(_, v) => {
+                        tr_base.project_downcast(bcx, v)
                     }
-                };
-                LvalueRef {
-                    llval: llprojected,
-                    llextra,
-                    ty: projected_ty,
-                    alignment: align,
                 }
             }
         };
diff --git a/src/librustc_trans/mir/mod.rs b/src/librustc_trans/mir/mod.rs
index 1cb13c973f9..c82a9317a02 100644
--- a/src/librustc_trans/mir/mod.rs
+++ b/src/librustc_trans/mir/mod.rs
@@ -14,7 +14,6 @@ use llvm::debuginfo::DIScope;
 use rustc::ty::{self, Ty, TypeFoldable};
 use rustc::ty::layout::{self, LayoutTyper};
 use rustc::mir::{self, Mir};
-use rustc::mir::tcx::LvalueTy;
 use rustc::ty::subst::Substs;
 use rustc::infer::TransNormalize;
 use rustc::session::config::FullDebugInfo;
@@ -23,7 +22,7 @@ use builder::Builder;
 use common::{self, CrateContext, Funclet};
 use debuginfo::{self, declare_local, VariableAccess, VariableKind, FunctionDebugContext};
 use monomorphize::Instance;
-use abi::{ArgAttribute, FnType};
+use abi::{self, ArgAttribute, FnType};
 use type_of;
 
 use syntax_pos::{DUMMY_SP, NO_EXPANSION, BytePos, Span};
@@ -281,8 +280,7 @@ pub fn trans_mir<'a, 'tcx: 'a>(
                 if local == mir::RETURN_POINTER && mircx.fn_ty.ret.is_indirect() {
                     debug!("alloc: {:?} (return pointer) -> lvalue", local);
                     let llretptr = llvm::get_param(llfn, 0);
-                    LocalRef::Lvalue(LvalueRef::new_sized(llretptr, LvalueTy::from_ty(ty),
-                                                          Alignment::AbiAligned))
+                    LocalRef::Lvalue(LvalueRef::new_sized(llretptr, ty, Alignment::AbiAligned))
                 } else if lvalue_locals.contains(local.index()) {
                     debug!("alloc: {:?} -> lvalue", local);
                     assert!(!ty.has_erasable_regions());
@@ -404,7 +402,7 @@ fn arg_local_refs<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
 
             let lvalue = LvalueRef::alloca(bcx, arg_ty, &name);
             for (i, &tupled_arg_ty) in tupled_arg_tys.iter().enumerate() {
-                let (dst, _) = lvalue.trans_field_ptr(bcx, i);
+                let dst = lvalue.project_field(bcx, i);
                 let arg = &mircx.fn_ty.args[idx];
                 idx += 1;
                 if common::type_is_fat_ptr(bcx.ccx, tupled_arg_ty) {
@@ -412,8 +410,10 @@ fn arg_local_refs<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
                     // they are the two sub-fields of a single aggregate field.
                     let meta = &mircx.fn_ty.args[idx];
                     idx += 1;
-                    arg.store_fn_arg(bcx, &mut llarg_idx, base::get_dataptr(bcx, dst));
-                    meta.store_fn_arg(bcx, &mut llarg_idx, base::get_meta(bcx, dst));
+                    arg.store_fn_arg(bcx, &mut llarg_idx,
+                        dst.project_field(bcx, abi::FAT_PTR_ADDR));
+                    meta.store_fn_arg(bcx, &mut llarg_idx,
+                        dst.project_field(bcx, abi::FAT_PTR_EXTRA));
                 } else {
                     arg.store_fn_arg(bcx, &mut llarg_idx, dst);
                 }
@@ -441,7 +441,7 @@ fn arg_local_refs<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
 
         let arg = &mircx.fn_ty.args[idx];
         idx += 1;
-        let llval = if arg.is_indirect() {
+        let lvalue = if arg.is_indirect() {
             // Don't copy an indirect argument to an alloca, the caller
             // already put it in a temporary alloca and gave it up
             // FIXME: lifetimes
@@ -451,7 +451,7 @@ fn arg_local_refs<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
             let llarg = llvm::get_param(bcx.llfn(), llarg_idx as c_uint);
             bcx.set_value_name(llarg, &name);
             llarg_idx += 1;
-            llarg
+            LvalueRef::new_sized(llarg, arg_ty, Alignment::AbiAligned)
         } else if !lvalue_locals.contains(local.index()) &&
                   arg.cast.is_none() && arg_scope.is_none() {
             if arg.is_ignore() {
@@ -502,21 +502,21 @@ fn arg_local_refs<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
             };
             return LocalRef::Operand(Some(operand.unpack_if_pair(bcx)));
         } else {
-            let lltemp = LvalueRef::alloca(bcx, arg_ty, &name);
+            let tmp = LvalueRef::alloca(bcx, arg_ty, &name);
             if common::type_is_fat_ptr(bcx.ccx, arg_ty) {
                 // we pass fat pointers as two words, but we want to
                 // represent them internally as a pointer to two words,
                 // so make an alloca to store them in.
                 let meta = &mircx.fn_ty.args[idx];
                 idx += 1;
-                arg.store_fn_arg(bcx, &mut llarg_idx, base::get_dataptr(bcx, lltemp.llval));
-                meta.store_fn_arg(bcx, &mut llarg_idx, base::get_meta(bcx, lltemp.llval));
+                arg.store_fn_arg(bcx, &mut llarg_idx, tmp.project_field(bcx, abi::FAT_PTR_ADDR));
+                meta.store_fn_arg(bcx, &mut llarg_idx, tmp.project_field(bcx, abi::FAT_PTR_EXTRA));
             } else  {
                 // otherwise, arg is passed by value, so make a
                 // temporary and store it there
-                arg.store_fn_arg(bcx, &mut llarg_idx, lltemp.llval);
+                arg.store_fn_arg(bcx, &mut llarg_idx, tmp);
             }
-            lltemp.llval
+            tmp
         };
         arg_scope.map(|scope| {
             // Is this a regular argument?
@@ -527,11 +527,11 @@ fn arg_local_refs<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
                 let variable_access = if arg.is_indirect() &&
                     !arg.attrs.contains(ArgAttribute::ByVal) {
                     VariableAccess::IndirectVariable {
-                        alloca: llval,
+                        alloca: lvalue.llval,
                         address_operations: &deref_op,
                     }
                 } else {
-                    VariableAccess::DirectVariable { alloca: llval }
+                    VariableAccess::DirectVariable { alloca: lvalue.llval }
                 };
 
                 declare_local(
@@ -567,11 +567,12 @@ fn arg_local_refs<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
             // doesn't actually strip the offset when splitting the closure
             // environment into its components so it ends up out of bounds.
             let env_ptr = if !env_ref {
-                let alloc = bcx.alloca(common::val_ty(llval), "__debuginfo_env_ptr", None);
-                bcx.store(llval, alloc, None);
-                alloc
+                let alloc_ty = tcx.mk_mut_ptr(arg_ty);
+                let alloc = LvalueRef::alloca(bcx, alloc_ty, "__debuginfo_env_ptr");
+                bcx.store(lvalue.llval, alloc.llval, None);
+                alloc.llval
             } else {
-                llval
+                lvalue.llval
             };
 
             let layout = bcx.ccx.layout_of(closure_ty);
@@ -619,8 +620,7 @@ fn arg_local_refs<'a, 'tcx>(bcx: &Builder<'a, 'tcx>,
                 );
             }
         });
-        LocalRef::Lvalue(LvalueRef::new_sized(llval, LvalueTy::from_ty(arg_ty),
-                                              Alignment::AbiAligned))
+        LocalRef::Lvalue(lvalue)
     }).collect()
 }
 
@@ -628,6 +628,6 @@ mod analyze;
 mod block;
 mod constant;
 pub mod lvalue;
-mod operand;
+pub mod operand;
 mod rvalue;
 mod statement;
diff --git a/src/librustc_trans/mir/operand.rs b/src/librustc_trans/mir/operand.rs
index f4285c2ad0a..85bd99fed14 100644
--- a/src/librustc_trans/mir/operand.rs
+++ b/src/librustc_trans/mir/operand.rs
@@ -10,18 +10,16 @@
 
 use llvm::ValueRef;
 use rustc::ty::{self, Ty};
-use rustc::ty::layout::{Align, Layout, LayoutTyper};
+use rustc::ty::layout::LayoutTyper;
 use rustc::mir;
 use rustc::mir::tcx::LvalueTy;
 use rustc_data_structures::indexed_vec::Idx;
 
-use adt;
 use base;
 use common::{self, CrateContext, C_undef};
 use builder::Builder;
 use value::Value;
-use type_of;
-use type_::Type;
+use type_of::{self, LayoutLlvmExt};
 
 use std::fmt;
 use std::ptr;
@@ -49,8 +47,8 @@ pub enum OperandValue {
 ///
 /// NOTE: unless you know a value's type exactly, you should not
 /// generate LLVM opcodes acting on it and instead act via methods,
-/// to avoid nasty edge cases. In particular, using `Builder.store`
-/// directly is sure to cause problems -- use `MirContext.store_operand`
+/// to avoid nasty edge cases. In particular, using `Builder::store`
+/// directly is sure to cause problems -- use `OperandRef::store`
 /// instead.
 #[derive(Copy, Clone)]
 pub struct OperandRef<'tcx> {
@@ -121,15 +119,10 @@ impl<'a, 'tcx> OperandRef<'tcx> {
             let llty = type_of::type_of(bcx.ccx, self.ty);
             let mut llpair = C_undef(llty);
             let elems = [a, b];
+            let layout = bcx.ccx.layout_of(self.ty);
             for i in 0..2 {
                 let elem = base::from_immediate(bcx, elems[i]);
-                let layout = bcx.ccx.layout_of(self.ty);
-                let i = if let Layout::Univariant { ref variant, .. } = *layout {
-                    adt::struct_llfields_index(variant, i)
-                } else {
-                    i
-                };
-                llpair = bcx.insert_value(llpair, elem, i);
+                llpair = bcx.insert_value(llpair, elem, layout.llvm_field_index(i));
             }
             self.val = OperandValue::Immediate(llpair);
         }
@@ -145,72 +138,51 @@ impl<'a, 'tcx> OperandRef<'tcx> {
                 debug!("Operand::unpack_if_pair: unpacking {:?}", self);
 
                 let layout = bcx.ccx.layout_of(self.ty);
-                let (ix0, ix1) = if let Layout::Univariant { ref variant, .. } = *layout {
-                    (adt::struct_llfields_index(variant, 0),
-                    adt::struct_llfields_index(variant, 1))
-                } else {
-                    (0, 1)
-                };
 
-                let mut a = bcx.extract_value(llval, ix0);
-                let mut b = bcx.extract_value(llval, ix1);
+                let a = bcx.extract_value(llval, layout.llvm_field_index(0));
+                let a = base::to_immediate(bcx, a, layout.field_type(bcx.ccx, 0));
 
-                let pair_fields = common::type_pair_fields(bcx.ccx, self.ty);
-                if let Some([a_ty, b_ty]) = pair_fields {
-                    if a_ty.is_bool() {
-                        a = bcx.trunc(a, Type::i1(bcx.ccx));
-                    }
-                    if b_ty.is_bool() {
-                        b = bcx.trunc(b, Type::i1(bcx.ccx));
-                    }
-                }
+                let b = bcx.extract_value(llval, layout.llvm_field_index(1));
+                let b = base::to_immediate(bcx, b, layout.field_type(bcx.ccx, 1));
 
                 self.val = OperandValue::Pair(a, b);
             }
         }
         self
     }
-}
-
-impl<'a, 'tcx> MirContext<'a, 'tcx> {
-    pub fn trans_load(&mut self,
-                      bcx: &Builder<'a, 'tcx>,
-                      llval: ValueRef,
-                      align: Alignment,
-                      ty: Ty<'tcx>)
-                      -> OperandRef<'tcx>
-    {
-        debug!("trans_load: {:?} @ {:?}", Value(llval), ty);
-
-        let val = if common::type_is_fat_ptr(bcx.ccx, ty) {
-            let (lldata, llextra) = base::load_fat_ptr(bcx, llval, align, ty);
-            OperandValue::Pair(lldata, llextra)
-        } else if common::type_is_imm_pair(bcx.ccx, ty) {
-            let (ix0, ix1, f_align) = match *bcx.ccx.layout_of(ty) {
-                Layout::Univariant { ref variant, .. } => {
-                    (adt::struct_llfields_index(variant, 0),
-                    adt::struct_llfields_index(variant, 1),
-                    Alignment::from_packed(variant.packed) | align)
-                },
-                _ => (0, 1, align)
-            };
-            let [a_ty, b_ty] = common::type_pair_fields(bcx.ccx, ty).unwrap();
-            let a_ptr = bcx.struct_gep(llval, ix0);
-            let b_ptr = bcx.struct_gep(llval, ix1);
-
-            OperandValue::Pair(
-                base::load_ty(bcx, a_ptr, f_align, a_ty),
-                base::load_ty(bcx, b_ptr, f_align, b_ty)
-            )
-        } else if common::type_is_immediate(bcx.ccx, ty) {
-            OperandValue::Immediate(base::load_ty(bcx, llval, align, ty))
-        } else {
-            OperandValue::Ref(llval, align)
-        };
 
-        OperandRef { val: val, ty: ty }
+    pub fn store(self, bcx: &Builder<'a, 'tcx>, dest: LvalueRef<'tcx>) {
+        debug!("OperandRef::store: operand={:?}, dest={:?}", self, dest);
+        // Avoid generating stores of zero-sized values, because the only way to have a zero-sized
+        // value is through `undef`, and store itself is useless.
+        if common::type_is_zero_size(bcx.ccx, self.ty) {
+            return;
+        }
+        match self.val {
+            OperandValue::Ref(r, source_align) =>
+                base::memcpy_ty(bcx, dest.llval, r, self.ty,
+                                (source_align | dest.alignment).non_abi()),
+            OperandValue::Immediate(s) => {
+                bcx.store(base::from_immediate(bcx, s), dest.llval, dest.alignment.non_abi());
+            }
+            OperandValue::Pair(a, b) => {
+                // See comment above about zero-sized values.
+                let dest_a = dest.project_field(bcx, 0);
+                if !common::type_is_zero_size(bcx.ccx, dest_a.ty.to_ty(bcx.tcx())) {
+                    let a = base::from_immediate(bcx, a);
+                    bcx.store(a, dest_a.llval, dest_a.alignment.non_abi());
+                }
+                let dest_b = dest.project_field(bcx, 1);
+                if !common::type_is_zero_size(bcx.ccx, dest_b.ty.to_ty(bcx.tcx())) {
+                    let b = base::from_immediate(bcx, b);
+                    bcx.store(b, dest_b.llval, dest_b.alignment.non_abi());
+                }
+            }
+        }
     }
+}
 
+impl<'a, 'tcx> MirContext<'a, 'tcx> {
     pub fn trans_consume(&mut self,
                          bcx: &Builder<'a, 'tcx>,
                          lvalue: &mir::Lvalue<'tcx>)
@@ -258,9 +230,7 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
 
         // for most lvalues, to consume them we just load them
         // out from their home
-        let tr_lvalue = self.trans_lvalue(bcx, lvalue);
-        let ty = tr_lvalue.ty.to_ty(bcx.tcx());
-        self.trans_load(bcx, tr_lvalue.llval, tr_lvalue.alignment, ty)
+        self.trans_lvalue(bcx, lvalue).load(bcx)
     }
 
     pub fn trans_operand(&mut self,
@@ -280,59 +250,11 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
                 let operand = val.to_operand(bcx.ccx);
                 if let OperandValue::Ref(ptr, align) = operand.val {
                     // If this is a OperandValue::Ref to an immediate constant, load it.
-                    self.trans_load(bcx, ptr, align, operand.ty)
+                    LvalueRef::new_sized(ptr, operand.ty, align).load(bcx)
                 } else {
                     operand
                 }
             }
         }
     }
-
-    pub fn store_operand(&mut self,
-                         bcx: &Builder<'a, 'tcx>,
-                         lldest: ValueRef,
-                         align: Option<Align>,
-                         operand: OperandRef<'tcx>) {
-        debug!("store_operand: operand={:?}, align={:?}", operand, align);
-        // Avoid generating stores of zero-sized values, because the only way to have a zero-sized
-        // value is through `undef`, and store itself is useless.
-        if common::type_is_zero_size(bcx.ccx, operand.ty) {
-            return;
-        }
-        match operand.val {
-            OperandValue::Ref(r, source_align) =>
-                base::memcpy_ty(bcx, lldest, r, operand.ty,
-                                source_align.min_with(align)),
-            OperandValue::Immediate(s) => {
-                bcx.store(base::from_immediate(bcx, s), lldest, align);
-            }
-            OperandValue::Pair(a, b) => {
-                let (ix0, ix1, f_align) = match *bcx.ccx.layout_of(operand.ty) {
-                    Layout::Univariant { ref variant, .. } => {
-                        (adt::struct_llfields_index(variant, 0),
-                        adt::struct_llfields_index(variant, 1),
-                        if variant.packed { Some(variant.align) } else { None })
-                    }
-                    _ => (0, 1, align)
-                };
-
-                let a = base::from_immediate(bcx, a);
-                let b = base::from_immediate(bcx, b);
-
-                // See comment above about zero-sized values.
-                let (a_zst, b_zst) = common::type_pair_fields(bcx.ccx, operand.ty)
-                    .map_or((false, false), |[a_ty, b_ty]| {
-                        (common::type_is_zero_size(bcx.ccx, a_ty),
-                         common::type_is_zero_size(bcx.ccx, b_ty))
-                    });
-
-                if !a_zst {
-                    bcx.store(a, bcx.struct_gep(lldest, ix0), f_align);
-                }
-                if !b_zst {
-                    bcx.store(b, bcx.struct_gep(lldest, ix1), f_align);
-                }
-            }
-        }
-    }
 }
diff --git a/src/librustc_trans/mir/rvalue.rs b/src/librustc_trans/mir/rvalue.rs
index d975ed8cda4..4f4fbcd6237 100644
--- a/src/librustc_trans/mir/rvalue.rs
+++ b/src/librustc_trans/mir/rvalue.rs
@@ -12,7 +12,6 @@ use llvm::{self, ValueRef};
 use rustc::ty::{self, Ty};
 use rustc::ty::cast::{CastTy, IntTy};
 use rustc::ty::layout::{Layout, LayoutTyper};
-use rustc::mir::tcx::LvalueTy;
 use rustc::mir;
 use rustc::middle::lang_items::ExchangeMallocFnLangItem;
 use rustc_apfloat::{ieee, Float, Status, Round};
@@ -25,11 +24,9 @@ use callee;
 use common::{self, val_ty};
 use common::{C_bool, C_u8, C_i32, C_u32, C_u64, C_null, C_usize, C_uint, C_big_integral};
 use consts;
-use adt;
 use monomorphize;
 use type_::Type;
 use type_of;
-use tvec;
 use value::Value;
 
 use super::{MirContext, LocalRef};
@@ -52,7 +49,7 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
                let tr_operand = self.trans_operand(&bcx, operand);
                // FIXME: consider not copying constants through stack. (fixable by translating
                // constants into OperandValue::Ref, why don’t we do that yet if we don’t?)
-               self.store_operand(&bcx, dest.llval, dest.alignment.to_align(), tr_operand);
+               tr_operand.store(&bcx, dest);
                bcx
            }
 
@@ -63,7 +60,7 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
                     // into-coerce of a thin pointer to a fat pointer - just
                     // use the operand path.
                     let (bcx, temp) = self.trans_rvalue_operand(bcx, rvalue);
-                    self.store_operand(&bcx, dest.llval, dest.alignment.to_align(), temp);
+                    temp.store(&bcx, dest);
                     return bcx;
                 }
 
@@ -73,9 +70,9 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
                 // so the (generic) MIR may not be able to expand it.
                 let operand = self.trans_operand(&bcx, source);
                 let operand = operand.pack_if_pair(&bcx);
-                let llref = match operand.val {
+                match operand.val {
                     OperandValue::Pair(..) => bug!(),
-                    OperandValue::Immediate(llval) => {
+                    OperandValue::Immediate(_) => {
                         // unsize from an immediate structure. We don't
                         // really need a temporary alloca here, but
                         // avoiding it would require us to have
@@ -84,101 +81,93 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
                         // important enough for it.
                         debug!("trans_rvalue: creating ugly alloca");
                         let scratch = LvalueRef::alloca(&bcx, operand.ty, "__unsize_temp");
-                        base::store_ty(&bcx, llval, scratch.llval, scratch.alignment, operand.ty);
-                        scratch
+                        scratch.storage_live(&bcx);
+                        operand.store(&bcx, scratch);
+                        base::coerce_unsized_into(&bcx, scratch, dest);
+                        scratch.storage_dead(&bcx);
                     }
                     OperandValue::Ref(llref, align) => {
-                        LvalueRef::new_sized_ty(llref, operand.ty, align)
+                        let source = LvalueRef::new_sized(llref, operand.ty, align);
+                        base::coerce_unsized_into(&bcx, source, dest);
                     }
-                };
-                base::coerce_unsized_into(&bcx, &llref, &dest);
+                }
                 bcx
             }
 
             mir::Rvalue::Repeat(ref elem, count) => {
-                let dest_ty = dest.ty.to_ty(bcx.tcx());
+                let tr_elem = self.trans_operand(&bcx, elem);
 
-                // No need to inizialize memory of a zero-sized slice
+                // Do not generate the loop for zero-sized elements or empty arrays.
+                let dest_ty = dest.ty.to_ty(bcx.tcx());
                 if common::type_is_zero_size(bcx.ccx, dest_ty) {
                     return bcx;
                 }
 
-                let tr_elem = self.trans_operand(&bcx, elem);
-                let count = count.as_u64();
-                let count = C_usize(bcx.ccx, count);
-                let base = base::get_dataptr(&bcx, dest.llval);
-                let align = dest.alignment.to_align();
+                let start = dest.project_index(&bcx, C_usize(bcx.ccx, 0)).llval;
 
                 if let OperandValue::Immediate(v) = tr_elem.val {
-                    let align = align.unwrap_or_else(|| bcx.ccx.align_of(tr_elem.ty));
+                    let align = dest.alignment.non_abi()
+                        .unwrap_or_else(|| bcx.ccx.align_of(tr_elem.ty));
                     let align = C_i32(bcx.ccx, align.abi() as i32);
                     let size = C_usize(bcx.ccx, bcx.ccx.size_of(dest_ty).bytes());
 
                     // Use llvm.memset.p0i8.* to initialize all zero arrays
                     if common::is_const_integral(v) && common::const_to_uint(v) == 0 {
                         let fill = C_u8(bcx.ccx, 0);
-                        base::call_memset(&bcx, base, fill, size, align, false);
+                        base::call_memset(&bcx, start, fill, size, align, false);
                         return bcx;
                     }
 
                     // Use llvm.memset.p0i8.* to initialize byte arrays
                     if common::val_ty(v) == Type::i8(bcx.ccx) {
-                        base::call_memset(&bcx, base, v, size, align, false);
+                        base::call_memset(&bcx, start, v, size, align, false);
                         return bcx;
                     }
                 }
 
-                tvec::slice_for_each(&bcx, base, tr_elem.ty, count, |bcx, llslot, loop_bb| {
-                    self.store_operand(bcx, llslot, align, tr_elem);
-                    bcx.br(loop_bb);
-                })
+                let count = count.as_u64();
+                let count = C_usize(bcx.ccx, count);
+                let end = dest.project_index(&bcx, count).llval;
+
+                let header_bcx = bcx.build_sibling_block("repeat_loop_header");
+                let body_bcx = bcx.build_sibling_block("repeat_loop_body");
+                let next_bcx = bcx.build_sibling_block("repeat_loop_next");
+
+                bcx.br(header_bcx.llbb());
+                let current = header_bcx.phi(common::val_ty(start), &[start], &[bcx.llbb()]);
+
+                let keep_going = header_bcx.icmp(llvm::IntNE, current, end);
+                header_bcx.cond_br(keep_going, body_bcx.llbb(), next_bcx.llbb());
+
+                tr_elem.store(&body_bcx,
+                    LvalueRef::new_sized(current, tr_elem.ty, dest.alignment));
+
+                let next = body_bcx.inbounds_gep(current, &[C_usize(bcx.ccx, 1)]);
+                body_bcx.br(header_bcx.llbb());
+                header_bcx.add_incoming_to_phi(current, next, body_bcx.llbb());
+
+                next_bcx
             }
 
             mir::Rvalue::Aggregate(ref kind, ref operands) => {
-                match **kind {
-                    mir::AggregateKind::Adt(adt_def, variant_index, substs, active_field_index) => {
+                let (dest, active_field_index) = match **kind {
+                    mir::AggregateKind::Adt(adt_def, variant_index, _, active_field_index) => {
                         dest.trans_set_discr(&bcx, variant_index);
-                        for (i, operand) in operands.iter().enumerate() {
-                            let op = self.trans_operand(&bcx, operand);
-                            // Do not generate stores and GEPis for zero-sized fields.
-                            if !common::type_is_zero_size(bcx.ccx, op.ty) {
-                                let mut val = LvalueRef::new_sized(
-                                    dest.llval, dest.ty, dest.alignment);
-                                let field_index = active_field_index.unwrap_or(i);
-                                val.ty = LvalueTy::Downcast {
-                                    adt_def,
-                                    substs: self.monomorphize(&substs),
-                                    variant_index,
-                                };
-                                let (lldest_i, align) = val.trans_field_ptr(&bcx, field_index);
-                                self.store_operand(&bcx, lldest_i, align.to_align(), op);
-                            }
-                        }
-                    },
-                    _ => {
-                        // If this is a tuple or closure, we need to translate GEP indices.
-                        let layout = bcx.ccx.layout_of(dest.ty.to_ty(bcx.tcx()));
-                        let get_memory_index = |i| {
-                            if let Layout::Univariant { ref variant, .. } = *layout {
-                                adt::struct_llfields_index(variant, i)
-                            } else {
-                                i
-                            }
-                        };
-                        let alignment = dest.alignment;
-                        for (i, operand) in operands.iter().enumerate() {
-                            let op = self.trans_operand(&bcx, operand);
-                            // Do not generate stores and GEPis for zero-sized fields.
-                            if !common::type_is_zero_size(bcx.ccx, op.ty) {
-                                // Note: perhaps this should be StructGep, but
-                                // note that in some cases the values here will
-                                // not be structs but arrays.
-                                let i = get_memory_index(i);
-                                let dest = bcx.gepi(dest.llval, &[0, i]);
-                                self.store_operand(&bcx, dest, alignment.to_align(), op);
-                            }
+                        if adt_def.is_enum() {
+                            (dest.project_downcast(&bcx, variant_index), active_field_index)
+                        } else {
+                            (dest, active_field_index)
                         }
                     }
+                    _ => (dest, None)
+                };
+                for (i, operand) in operands.iter().enumerate() {
+                    let op = self.trans_operand(&bcx, operand);
+                    // Do not generate stores and GEPis for zero-sized fields.
+                    if !common::type_is_zero_size(bcx.ccx, op.ty) {
+                        let field_index = active_field_index.unwrap_or(i);
+                        op.store(&bcx, dest.project_field(&bcx, field_index));
+                    }
                 }
                 bcx
             }
@@ -186,7 +175,7 @@ impl<'a, 'tcx> MirContext<'a, 'tcx> {
             _ => {
                 assert!(self.rvalue_creates_operand(rvalue));
                 let (bcx, temp) = self.trans_rvalue_operand(bcx, rvalue);
-                self.store_operand(&bcx, dest.llval, dest.alignment.to_align(), temp);
+                temp.store(&bcx, dest);
                 bcx
             }
         }
diff --git a/src/librustc_trans/tvec.rs b/src/librustc_trans/tvec.rs
deleted file mode 100644
index da4a4e55a67..00000000000
--- a/src/librustc_trans/tvec.rs
+++ /dev/null
@@ -1,53 +0,0 @@
-// Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-use llvm;
-use builder::Builder;
-use llvm::{BasicBlockRef, ValueRef};
-use common::*;
-use rustc::ty::Ty;
-
-pub fn slice_for_each<'a, 'tcx, F>(
-    bcx: &Builder<'a, 'tcx>,
-    data_ptr: ValueRef,
-    unit_ty: Ty<'tcx>,
-    len: ValueRef,
-    f: F
-) -> Builder<'a, 'tcx> where F: FnOnce(&Builder<'a, 'tcx>, ValueRef, BasicBlockRef) {
-    // Special-case vectors with elements of size 0  so they don't go out of bounds (#9890)
-    let zst = type_is_zero_size(bcx.ccx, unit_ty);
-    let add = |bcx: &Builder, a, b| if zst {
-        bcx.add(a, b)
-    } else {
-        bcx.inbounds_gep(a, &[b])
-    };
-
-    let body_bcx = bcx.build_sibling_block("slice_loop_body");
-    let header_bcx = bcx.build_sibling_block("slice_loop_header");
-    let next_bcx = bcx.build_sibling_block("slice_loop_next");
-
-    let start = if zst {
-        C_usize(bcx.ccx, 1)
-    } else {
-        data_ptr
-    };
-    let end = add(&bcx, start, len);
-
-    bcx.br(header_bcx.llbb());
-    let current = header_bcx.phi(val_ty(start), &[start], &[bcx.llbb()]);
-
-    let keep_going = header_bcx.icmp(llvm::IntNE, current, end);
-    header_bcx.cond_br(keep_going, body_bcx.llbb(), next_bcx.llbb());
-
-    let next = add(&body_bcx, current, C_usize(bcx.ccx, 1));
-    f(&body_bcx, if zst { data_ptr } else { current }, header_bcx.llbb());
-    header_bcx.add_incoming_to_phi(current, next, body_bcx.llbb());
-    next_bcx
-}
diff --git a/src/librustc_trans/type_of.rs b/src/librustc_trans/type_of.rs
index f74aec07087..1187ef1cd2f 100644
--- a/src/librustc_trans/type_of.rs
+++ b/src/librustc_trans/type_of.rs
@@ -12,7 +12,7 @@ use abi::FnType;
 use adt;
 use common::*;
 use rustc::ty::{self, Ty, TypeFoldable};
-use rustc::ty::layout::{Align, LayoutTyper, Size};
+use rustc::ty::layout::{Align, Layout, LayoutTyper, Size, TyLayout};
 use trans_item::DefPathBasedNames;
 use type_::Type;
 
@@ -237,6 +237,50 @@ impl<'a, 'tcx> CrateContext<'a, 'tcx> {
     }
 }
 
+pub trait LayoutLlvmExt {
+    fn llvm_field_index(&self, index: usize) -> u64;
+}
+
+impl<'tcx> LayoutLlvmExt for TyLayout<'tcx> {
+    fn llvm_field_index(&self, index: usize) -> u64 {
+        match **self {
+            Layout::Scalar { .. } |
+            Layout::CEnum { .. } |
+            Layout::UntaggedUnion { .. } |
+            Layout::RawNullablePointer { .. } => {
+                bug!("TyLayout::llvm_field_index({:?}): not applicable", self)
+            }
+
+            Layout::Vector { .. } |
+            Layout::Array { .. } |
+            Layout::FatPointer { .. } => {
+                index as u64
+            }
+
+            Layout::Univariant { ref variant, .. } => {
+                adt::memory_index_to_gep(variant.memory_index[index] as u64)
+            }
+
+            Layout::General { ref variants, .. } => {
+                if let Some(v) = self.variant_index {
+                    adt::memory_index_to_gep(variants[v].memory_index[index] as u64)
+                } else {
+                    assert_eq!(index, 0);
+                    index as u64
+                }
+            }
+
+            Layout::StructWrappedNullablePointer { nndiscr, ref nonnull, .. } => {
+                if self.variant_index == Some(nndiscr as usize) {
+                    adt::memory_index_to_gep(nonnull.memory_index[index] as u64)
+                } else {
+                    bug!("TyLayout::llvm_field_index({:?}): not applicable", self)
+                }
+            }
+        }
+    }
+}
+
 fn llvm_type_name<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>, ty: Ty<'tcx>) -> String {
     let mut name = String::with_capacity(32);
     let printer = DefPathBasedNames::new(cx.tcx(), true, true);
diff --git a/src/librustc_trans_utils/monomorphize.rs b/src/librustc_trans_utils/monomorphize.rs
index ab61dacf010..eee5c1d9ef2 100644
--- a/src/librustc_trans_utils/monomorphize.rs
+++ b/src/librustc_trans_utils/monomorphize.rs
@@ -12,7 +12,7 @@ use rustc::hir::def_id::DefId;
 use rustc::middle::lang_items::DropInPlaceFnLangItem;
 use rustc::traits;
 use rustc::ty::adjustment::CustomCoerceUnsized;
-use rustc::ty::subst::{Kind, Subst, Substs};
+use rustc::ty::subst::{Kind, Subst};
 use rustc::ty::{self, Ty, TyCtxt};
 
 pub use rustc::ty::Instance;
@@ -125,12 +125,3 @@ pub fn custom_coerce_unsize_info<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
     }
 }
 
-/// Returns the normalized type of a struct field
-pub fn field_ty<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
-                          param_substs: &Substs<'tcx>,
-                          f: &'tcx ty::FieldDef)
-                          -> Ty<'tcx>
-{
-    tcx.fully_normalize_associated_types_in(&f.ty(tcx, param_substs))
-}
-
diff --git a/src/test/codegen/slice-init.rs b/src/test/codegen/slice-init.rs
index 569d937c812..915db493fc2 100644
--- a/src/test/codegen/slice-init.rs
+++ b/src/test/codegen/slice-init.rs
@@ -15,7 +15,7 @@
 // CHECK-LABEL: @zero_sized_elem
 #[no_mangle]
 pub fn zero_sized_elem() {
-    // CHECK-NOT: br label %slice_loop_header{{.*}}
+    // CHECK-NOT: br label %repeat_loop_header{{.*}}
     // CHECK-NOT: call void @llvm.memset.p0i8
     let x = [(); 4];
     drop(&x);
@@ -24,7 +24,7 @@ pub fn zero_sized_elem() {
 // CHECK-LABEL: @zero_len_array
 #[no_mangle]
 pub fn zero_len_array() {
-    // CHECK-NOT: br label %slice_loop_header{{.*}}
+    // CHECK-NOT: br label %repeat_loop_header{{.*}}
     // CHECK-NOT: call void @llvm.memset.p0i8
     let x = [4; 0];
     drop(&x);
@@ -34,7 +34,7 @@ pub fn zero_len_array() {
 #[no_mangle]
 pub fn byte_array() {
     // CHECK: call void @llvm.memset.p0i8.i[[WIDTH:[0-9]+]](i8* {{.*}}, i8 7, i[[WIDTH]] 4
-    // CHECK-NOT: br label %slice_loop_header{{.*}}
+    // CHECK-NOT: br label %repeat_loop_header{{.*}}
     let x = [7u8; 4];
     drop(&x);
 }
@@ -50,7 +50,7 @@ enum Init {
 #[no_mangle]
 pub fn byte_enum_array() {
     // CHECK: call void @llvm.memset.p0i8.i[[WIDTH:[0-9]+]](i8* {{.*}}, i8 {{.*}}, i[[WIDTH]] 4
-    // CHECK-NOT: br label %slice_loop_header{{.*}}
+    // CHECK-NOT: br label %repeat_loop_header{{.*}}
     let x = [Init::Memset; 4];
     drop(&x);
 }
@@ -59,7 +59,7 @@ pub fn byte_enum_array() {
 #[no_mangle]
 pub fn zeroed_integer_array() {
     // CHECK: call void @llvm.memset.p0i8.i[[WIDTH:[0-9]+]](i8* {{.*}}, i8 0, i[[WIDTH]] 16
-    // CHECK-NOT: br label %slice_loop_header{{.*}}
+    // CHECK-NOT: br label %repeat_loop_header{{.*}}
     let x = [0u32; 4];
     drop(&x);
 }
@@ -67,7 +67,7 @@ pub fn zeroed_integer_array() {
 // CHECK-LABEL: @nonzero_integer_array
 #[no_mangle]
 pub fn nonzero_integer_array() {
-    // CHECK: br label %slice_loop_header{{.*}}
+    // CHECK: br label %repeat_loop_header{{.*}}
     // CHECK-NOT: call void @llvm.memset.p0i8
     let x = [0x1a_2b_3c_4d_u32; 4];
     drop(&x);