Pass around i1 as is instead of going through u8

Author: nox

src/librustc_trans/abi.rs

@@ -558,7 +558,7 @@ impl<'a, 'tcx> FnTypeExt<'a, 'tcx> for FnType<'tcx, Ty<'tcx>> {
         let llreturn_ty = match self.ret.mode {
             PassMode::Ignore => Type::void(cx),
             PassMode::Direct(_) | PassMode::Pair(..) => {
-                self.ret.layout.immediate_llvm_type(cx)
+                self.ret.layout.llvm_type(cx)
             }
             PassMode::Cast(cast) => cast.llvm_type(cx),
             PassMode::Indirect(_) => {
@@ -575,7 +575,7 @@ impl<'a, 'tcx> FnTypeExt<'a, 'tcx> for FnType<'tcx, Ty<'tcx>> {
 
             let llarg_ty = match arg.mode {
                 PassMode::Ignore => continue,
-                PassMode::Direct(_) => arg.layout.immediate_llvm_type(cx),
+                PassMode::Direct(_) => arg.layout.llvm_type(cx),
                 PassMode::Pair(..) => {
                     llargument_tys.push(arg.layout.scalar_pair_element_llvm_type(cx, 0));
                     llargument_tys.push(arg.layout.scalar_pair_element_llvm_type(cx, 1));

src/librustc_trans/base.rs

@@ -40,7 +40,7 @@ use rustc::middle::weak_lang_items;
 use rustc::mir::mono::{Linkage, Visibility, Stats};
 use rustc::middle::cstore::{EncodedMetadata};
 use rustc::ty::{self, Ty, TyCtxt};
-use rustc::ty::layout::{self, Align, TyLayout, LayoutOf};
+use rustc::ty::layout::{Align, TyLayout, LayoutOf};
 use rustc::ty::maps::Providers;
 use rustc::dep_graph::{DepNode, DepConstructor};
 use rustc::ty::subst::Kind;
@@ -387,23 +387,6 @@ pub fn call_assume<'a, 'tcx>(bx: &Builder<'a, 'tcx>, val: ValueRef) {
     bx.call(assume_intrinsic, &[val], None);
 }
 
-pub fn from_immediate(bx: &Builder, val: ValueRef) -> ValueRef {
-    if val_ty(val) == Type::i1(bx.cx) {
-        bx.zext(val, Type::i8(bx.cx))
-    } else {
-        val
-    }
-}
-
-pub fn to_immediate(bx: &Builder, val: ValueRef, layout: layout::TyLayout) -> ValueRef {
-    if let layout::Abi::Scalar(ref scalar) = layout.abi {
-        if scalar.is_bool() {
-            return bx.trunc(val, Type::i1(bx.cx));
-        }
-    }
-    val
-}
-
 pub fn call_memcpy(bx: &Builder,
                    dst: ValueRef,
                    src: ValueRef,

src/librustc_trans/intrinsic.rs

@@ -244,7 +244,7 @@ pub fn trans_intrinsic_call<'a, 'tcx>(bx: &Builder<'a, 'tcx>,
             unsafe {
                 llvm::LLVMSetAlignment(load, cx.align_of(tp_ty).abi() as u32);
             }
-            to_immediate(bx, load, cx.layout_of(tp_ty))
+            load
         },
         "volatile_store" => {
             let tp_ty = substs.type_at(0);
@@ -259,7 +259,7 @@ pub fn trans_intrinsic_call<'a, 'tcx>(bx: &Builder<'a, 'tcx>,
                     if dst.layout.is_zst() {
                         return;
                     }
-                    from_immediate(bx, args[1].immediate())
+                    args[1].immediate()
                 };
                 let ptr = bx.pointercast(dst.llval, val_ty(val).ptr_to());
                 let store = bx.volatile_store(val, ptr);
@@ -556,7 +556,7 @@ pub fn trans_intrinsic_call<'a, 'tcx>(bx: &Builder<'a, 'tcx>,
             let val = if let OperandValue::Ref(ptr, align) = args[1].val {
                 bx.load(ptr, align)
             } else {
-                from_immediate(bx, args[1].immediate())
+                args[1].immediate()
             };
             let ptr = bx.pointercast(dst.llval, val_ty(val).ptr_to());
             let store = bx.nontemporal_store(val, ptr);

src/librustc_trans/mir/block.rs

@@ -204,7 +204,7 @@ impl<'a, 'tcx> FunctionCx<'a, 'tcx> {
                     let (otherwise, targets) = targets.split_last().unwrap();
                     let switch = bx.switch(discr.immediate(),
                                             llblock(self, *otherwise), values.len());
-                    let switch_llty = bx.cx.layout_of(switch_ty).immediate_llvm_type(bx.cx);
+                    let switch_llty = bx.cx.layout_of(switch_ty).llvm_type(bx.cx);
                     for (&value, target) in values.iter().zip(targets) {
                         let llval = C_uint_big(switch_llty, value);
                         let llbb = llblock(self, *target);
@@ -651,8 +651,6 @@ impl<'a, 'tcx> FunctionCx<'a, 'tcx> {
                         bx.range_metadata(llval, 0..2);
                     }
                 }
-                // We store bools as i8 so we need to truncate to i1.
-                llval = base::to_immediate(bx, llval, arg.layout);
             }
         }
 

src/librustc_trans/mir/constant.rs

@@ -215,7 +215,7 @@ impl<'a, 'tcx> FunctionCx<'a, 'tcx> {
                             };
                             Ok(primval_to_llvm(
                                 bx.cx, prim, scalar,
-                                layout.immediate_llvm_type(bx.cx),
+                                layout.llvm_type(bx.cx),
                             ))
                         },
                         other => bug!("simd shuffle field {:?}, {}", other, constant.ty),

src/librustc_trans/mir/operand.rs

@@ -88,7 +88,7 @@ impl<'a, 'tcx> OperandRef<'tcx> {
                    layout: TyLayout<'tcx>) -> OperandRef<'tcx> {
         assert!(layout.is_zst());
         OperandRef {
-            val: OperandValue::Immediate(C_undef(layout.immediate_llvm_type(cx))),
+            val: OperandValue::Immediate(C_undef(layout.llvm_type(cx))),
             layout
         }
     }
@@ -113,7 +113,7 @@ impl<'a, 'tcx> OperandRef<'tcx> {
                     bx.cx,
                     x,
                     scalar,
-                    layout.immediate_llvm_type(bx.cx),
+                    layout.llvm_type(bx.cx),
                 );
                 OperandValue::Immediate(llval)
             },
@@ -226,7 +226,7 @@ impl<'a, 'tcx> OperandRef<'tcx> {
             // If we're uninhabited, or the field is ZST, it has no data.
             _ if self.layout.abi == layout::Abi::Uninhabited || field.is_zst() => {
                 return OperandRef {
-                    val: OperandValue::Immediate(C_undef(field.immediate_llvm_type(bx.cx))),
+                    val: OperandValue::Immediate(C_undef(field.llvm_type(bx.cx))),
                     layout: field
                 };
             }
@@ -263,7 +263,7 @@ impl<'a, 'tcx> OperandRef<'tcx> {
         // HACK(eddyb) have to bitcast pointers until LLVM removes pointee types.
         match val {
             OperandValue::Immediate(ref mut llval) => {
-                *llval = bx.bitcast(*llval, field.immediate_llvm_type(bx.cx));
+                *llval = bx.bitcast(*llval, field.llvm_type(bx.cx));
             }
             OperandValue::Pair(ref mut a, ref mut b) => {
                 *a = bx.bitcast(*a, field.scalar_pair_element_llvm_type(bx.cx, 0));
@@ -292,7 +292,7 @@ impl<'a, 'tcx> OperandValue {
                 base::memcpy_ty(bx, dest.llval, r, dest.layout,
                                 source_align.min(dest.align)),
             OperandValue::Immediate(s) => {
-                bx.store(base::from_immediate(bx, s), dest.llval, dest.align);
+                bx.store(s, dest.llval, dest.align);
             }
             OperandValue::Pair(a, b) => {
                 for (i, &x) in [a, b].iter().enumerate() {
@@ -301,7 +301,7 @@ impl<'a, 'tcx> OperandValue {
                     if common::val_ty(x) == Type::i1(bx.cx) {
                         llptr = bx.pointercast(llptr, Type::i8p(bx.cx));
                     }
-                    bx.store(base::from_immediate(bx, x), llptr, dest.align);
+                    bx.store(x, llptr, dest.align);
                 }
             }
         }

src/librustc_trans/mir/place.rs

@@ -93,7 +93,7 @@ impl<'a, 'tcx> PlaceRef<'tcx> {
         let scalar_load_metadata = |load, scalar: &layout::Scalar| {
             let vr = scalar.valid_range.clone();
             match scalar.value {
-                layout::Int(..) => {
+                layout::Int(..) if !scalar.is_bool() => {
                     let range = scalar.valid_range_exclusive(bx.cx);
                     if range.start != range.end {
                         bx.range_metadata(load, range);
@@ -124,21 +124,13 @@ impl<'a, 'tcx> PlaceRef<'tcx> {
                 }
                 load
             };
-            OperandValue::Immediate(base::to_immediate(bx, llval, self.layout))
+            OperandValue::Immediate(llval)
         } else if let layout::Abi::ScalarPair(ref a, ref b) = self.layout.abi {
             let load = |i, scalar: &layout::Scalar| {
-                let mut llptr = bx.struct_gep(self.llval, i as u64);
-                // Make sure to always load i1 as i8.
-                if scalar.is_bool() {
-                    llptr = bx.pointercast(llptr, Type::i8p(bx.cx));
-                }
+                let llptr = bx.struct_gep(self.llval, i as u64);
                 let load = bx.load(llptr, self.align);
                 scalar_load_metadata(load, scalar);
-                if scalar.is_bool() {
-                    bx.trunc(load, Type::i1(bx.cx))
-                } else {
-                    load
-                }
+                load
             };
             OperandValue::Pair(load(0, a), load(1, b))
         } else {
@@ -254,7 +246,7 @@ impl<'a, 'tcx> PlaceRef<'tcx> {
 
     /// Obtain the actual discriminant of a value.
     pub fn trans_get_discr(self, bx: &Builder<'a, 'tcx>, cast_to: Ty<'tcx>) -> ValueRef {
-        let cast_to = bx.cx.layout_of(cast_to).immediate_llvm_type(bx.cx);
+        let cast_to = bx.cx.layout_of(cast_to).llvm_type(bx.cx);
         if self.layout.abi == layout::Abi::Uninhabited {
             return C_undef(cast_to);
         }
@@ -286,7 +278,7 @@ impl<'a, 'tcx> PlaceRef<'tcx> {
                 niche_start,
                 ..
             } => {
-                let niche_llty = discr.layout.immediate_llvm_type(bx.cx);
+                let niche_llty = discr.layout.llvm_type(bx.cx);
                 if niche_variants.start() == niche_variants.end() {
                     // FIXME(eddyb) Check the actual primitive type here.
                     let niche_llval = if niche_start == 0 {
@@ -351,7 +343,7 @@ impl<'a, 'tcx> PlaceRef<'tcx> {
                     }
 
                     let niche = self.project_field(bx, 0);
-                    let niche_llty = niche.layout.immediate_llvm_type(bx.cx);
+                    let niche_llty = niche.layout.llvm_type(bx.cx);
                     let niche_value = ((variant_index - *niche_variants.start()) as u128)
                         .wrapping_add(niche_start);
                     // FIXME(eddyb) Check the actual primitive type here.

src/librustc_trans/mir/rvalue.rs

@@ -101,7 +101,7 @@ impl<'a, 'tcx> FunctionCx<'a, 'tcx> {
 
                 let start = dest.project_index(&bx, C_usize(bx.cx, 0)).llval;
 
-                if let OperandValue::Immediate(v) = tr_elem.val {
+                if let OperandValue::Immediate(mut v) = tr_elem.val {
                     let align = C_i32(bx.cx, dest.align.abi() as i32);
                     let size = C_usize(bx.cx, dest.layout.size.bytes());
 
@@ -113,7 +113,9 @@ impl<'a, 'tcx> FunctionCx<'a, 'tcx> {
                     }
 
                     // Use llvm.memset.p0i8.* to initialize byte arrays
-                    let v = base::from_immediate(&bx, v);
+                    if common::val_ty(v) == Type::i1(bx.cx) {
+                        v = bx.zext(v, Type::i8(bx.cx))
+                    }
                     if common::val_ty(v) == Type::i8(bx.cx) {
                         base::call_memset(&bx, start, v, size, align, false);
                         return bx;
@@ -256,7 +258,7 @@ impl<'a, 'tcx> FunctionCx<'a, 'tcx> {
                             } else { // cast to thin-ptr
                                 // Cast of fat-ptr to thin-ptr is an extraction of data-ptr and
                                 // pointer-cast of that pointer to desired pointer type.
-                                let llcast_ty = cast.immediate_llvm_type(bx.cx);
+                                let llcast_ty = cast.llvm_type(bx.cx);
                                 let llval = bx.pointercast(data_ptr, llcast_ty);
                                 OperandValue::Immediate(llval)
                             }
@@ -266,7 +268,7 @@ impl<'a, 'tcx> FunctionCx<'a, 'tcx> {
                     }
                     mir::CastKind::Misc => {
                         assert!(cast.is_llvm_immediate());
-                        let ll_t_out = cast.immediate_llvm_type(bx.cx);
+                        let ll_t_out = cast.llvm_type(bx.cx);
                         if operand.layout.abi == layout::Abi::Uninhabited {
                             return (bx, OperandRef {
                                 val: OperandValue::Immediate(C_undef(ll_t_out)),
@@ -276,7 +278,7 @@ impl<'a, 'tcx> FunctionCx<'a, 'tcx> {
                         let r_t_in = CastTy::from_ty(operand.layout.ty)
                             .expect("bad input type for cast");
                         let r_t_out = CastTy::from_ty(cast.ty).expect("bad output type for cast");
-                        let ll_t_in = operand.layout.immediate_llvm_type(bx.cx);
+                        let ll_t_in = operand.layout.llvm_type(bx.cx);
                         match operand.layout.variants {
                             layout::Variants::Single { index } => {
                                 if let Some(def) = operand.layout.ty.ty_adt_def() {

src/librustc_trans/type_of.rs

@@ -200,7 +200,6 @@ pub trait LayoutLlvmExt<'tcx> {
     fn is_llvm_immediate(&self) -> bool;
     fn is_llvm_scalar_pair<'a>(&self) -> bool;
     fn llvm_type<'a>(&self, cx: &CodegenCx<'a, 'tcx>) -> Type;
-    fn immediate_llvm_type<'a>(&self, cx: &CodegenCx<'a, 'tcx>) -> Type;
     fn scalar_llvm_type_at<'a>(&self, cx: &CodegenCx<'a, 'tcx>,
                                scalar: &layout::Scalar, offset: Size) -> Type;
     fn scalar_pair_element_llvm_type<'a>(&self, cx: &CodegenCx<'a, 'tcx>,
@@ -244,6 +243,9 @@ impl<'tcx> LayoutLlvmExt<'tcx> for TyLayout<'tcx> {
     /// that field and ensuring the struct has the right alignment.
     fn llvm_type<'a>(&self, cx: &CodegenCx<'a, 'tcx>) -> Type {
         if let layout::Abi::Scalar(ref scalar) = self.abi {
+            if scalar.is_bool() {
+                return Type::i1(cx);
+            }
             // Use a different cache for scalars because pointers to DSTs
             // can be either fat or thin (data pointers of fat pointers).
             if let Some(&llty) = cx.scalar_lltypes.borrow().get(&self.ty) {
@@ -310,15 +312,6 @@ impl<'tcx> LayoutLlvmExt<'tcx> for TyLayout<'tcx> {
         llty
     }
 
-    fn immediate_llvm_type<'a>(&self, cx: &CodegenCx<'a, 'tcx>) -> Type {
-        if let layout::Abi::Scalar(ref scalar) = self.abi {
-            if scalar.is_bool() {
-                return Type::i1(cx);
-            }
-        }
-        self.llvm_type(cx)
-    }
-
     fn scalar_llvm_type_at<'a>(&self, cx: &CodegenCx<'a, 'tcx>,
                                scalar: &layout::Scalar, offset: Size) -> Type {
         match scalar.value {
@@ -359,13 +352,6 @@ impl<'tcx> LayoutLlvmExt<'tcx> for TyLayout<'tcx> {
         };
         let scalar = [a, b][index];
 
-        // Make sure to return the same type `immediate_llvm_type` would,
-        // to avoid dealing with two types and the associated conversions.
-        // This means that `(bool, bool)` is represented as `{i1, i1}`,
-        // both in memory and as an immediate, while `bool` is typically
-        // `i8` in memory and only `i1` when immediate. While we need to
-        // load/store `bool` as `i8` to avoid crippling LLVM optimizations,
-        // `i1` in a LLVM aggregate is valid and mostly equivalent to `i8`.
         if scalar.is_bool() {
             return Type::i1(cx);
         }

src/test/codegen/function-arguments.rs

@@ -151,7 +151,7 @@ pub fn enum_id_1(x: Option<Result<u16, u16>>) -> Option<Result<u16, u16>> {
   x
 }
 
-// CHECK: i16 @enum_id_2(i16)
+// CHECK: { i1, i8 } @enum_id_2(i1 zeroext %x.0, i8 %x.1)
 #[no_mangle]
 pub fn enum_id_2(x: Option<u8>) -> Option<u8> {
   x