]> git.lizzy.rs Git - rust.git/blobdiff - src/base.rs
Use don't unroll loop in Rvalue::Repeat
[rust.git] / src / base.rs
index acdfba4323af3fe9e4162b9982cf9848a4e0f5d9..cae2115ab181b630f67b1e090df951313c953e0c 100644 (file)
@@ -1,5 +1,5 @@
-use rustc_middle::ty::adjustment::PointerCast;
 use rustc_index::vec::IndexVec;
+use rustc_middle::ty::adjustment::PointerCast;
 
 use crate::prelude::*;
 
@@ -15,31 +15,31 @@ pub(crate) fn trans_fn<'tcx, B: Backend + 'static>(
     // Declare function
     let (name, sig) = get_function_name_and_sig(tcx, cx.module.isa().triple(), instance, false);
     let func_id = cx.module.declare_function(&name, linkage, &sig).unwrap();
-    let mut debug_context = cx
-        .debug_context
-        .as_mut()
-        .map(|debug_context| FunctionDebugContext::new(debug_context, instance, func_id, &name));
 
-    // Make FunctionBuilder
-    let context = &mut cx.cached_context;
-    context.clear();
-    context.func.name = ExternalName::user(0, func_id.as_u32());
-    context.func.signature = sig;
-    context.func.collect_debug_info();
+    cx.cached_context.clear();
+
+    // Make the FunctionBuilder
     let mut func_ctx = FunctionBuilderContext::new();
-    let mut bcx = FunctionBuilder::new(&mut context.func, &mut func_ctx);
+    let mut func = std::mem::replace(&mut cx.cached_context.func, Function::new());
+    func.name = ExternalName::user(0, func_id.as_u32());
+    func.signature = sig;
+    func.collect_debug_info();
+
+    let mut bcx = FunctionBuilder::new(&mut func, &mut func_ctx);
 
     // Predefine blocks
     let start_block = bcx.create_block();
-    let block_map: IndexVec<BasicBlock, Block> = (0..mir.basic_blocks().len()).map(|_| bcx.create_block()).collect();
+    let block_map: IndexVec<BasicBlock, Block> = (0..mir.basic_blocks().len())
+        .map(|_| bcx.create_block())
+        .collect();
 
     // Make FunctionCx
     let pointer_type = cx.module.target_config().pointer_type();
     let clif_comments = crate::pretty_clif::CommentWriter::new(tcx, instance);
 
     let mut fx = FunctionCx {
+        cx,
         tcx,
-        module: &mut cx.module,
         pointer_type,
 
         instance,
@@ -52,20 +52,28 @@ pub(crate) fn trans_fn<'tcx, B: Backend + 'static>(
         cold_blocks: EntitySet::new(),
 
         clif_comments,
-        constants_cx: &mut cx.constants_cx,
-        vtables: &mut cx.vtables,
         source_info_set: indexmap::IndexSet::new(),
+        next_ssa_var: 0,
+
+        inline_asm_index: 0,
     };
 
-    let arg_uninhabited = fx.mir.args_iter().any(|arg| fx.layout_of(fx.monomorphize(&fx.mir.local_decls[arg].ty)).abi.is_uninhabited());
+    let arg_uninhabited = fx.mir.args_iter().any(|arg| {
+        fx.layout_of(fx.monomorphize(&fx.mir.local_decls[arg].ty))
+            .abi
+            .is_uninhabited()
+    });
 
     if arg_uninhabited {
-        fx.bcx.append_block_params_for_function_params(fx.block_map[START_BLOCK]);
+        fx.bcx
+            .append_block_params_for_function_params(fx.block_map[START_BLOCK]);
         fx.bcx.switch_to_block(fx.block_map[START_BLOCK]);
         crate::trap::trap_unreachable(&mut fx, "function has uninhabited argument");
     } else {
         tcx.sess.time("codegen clif ir", || {
-            tcx.sess.time("codegen prelude", || crate::abi::codegen_fn_prelude(&mut fx, start_block, true));
+            tcx.sess.time("codegen prelude", || {
+                crate::abi::codegen_fn_prelude(&mut fx, start_block)
+            });
             codegen_fn_content(&mut fx);
         });
     }
@@ -77,56 +85,71 @@ pub(crate) fn trans_fn<'tcx, B: Backend + 'static>(
     let local_map = fx.local_map;
     let cold_blocks = fx.cold_blocks;
 
-    crate::pretty_clif::write_clif_file(cx.tcx, "unopt", instance, &context.func, &clif_comments, None);
+    // Store function in context
+    let context = &mut cx.cached_context;
+    context.func = func;
+
+    crate::pretty_clif::write_clif_file(tcx, "unopt", None, instance, &context, &clif_comments);
 
     // Verify function
     verify_func(tcx, &clif_comments, &context.func);
 
     // Perform rust specific optimizations
     tcx.sess.time("optimize clif ir", || {
-        crate::optimize::optimize_function(tcx, instance, context, &cold_blocks, &mut clif_comments);
+        crate::optimize::optimize_function(
+            tcx,
+            instance,
+            context,
+            &cold_blocks,
+            &mut clif_comments,
+        );
     });
 
-    // If the return block is not reachable, then the SSA builder may have inserted a `iconst.i128`
+    // If the return block is not reachable, then the SSA builder may have inserted an `iconst.i128`
     // instruction, which doesn't have an encoding.
     context.compute_cfg();
     context.compute_domtree();
     context.eliminate_unreachable_code(cx.module.isa()).unwrap();
+    context.dce(cx.module.isa()).unwrap();
 
     // Define function
     let module = &mut cx.module;
-    tcx.sess.time(
-        "define function",
-        || module.define_function(
-            func_id,
-            context,
-            &mut cranelift_codegen::binemit::NullTrapSink {},
-        ).unwrap(),
-    );
+    tcx.sess.time("define function", || {
+        module
+            .define_function(
+                func_id,
+                context,
+                &mut cranelift_codegen::binemit::NullTrapSink {},
+            )
+            .unwrap()
+    });
 
     // Write optimized function to file for debugging
-    {
-        let value_ranges = context
-            .build_value_labels_ranges(cx.module.isa())
-            .expect("value location ranges");
-
-        crate::pretty_clif::write_clif_file(
-            cx.tcx,
-            "opt",
-            instance,
-            &context.func,
-            &clif_comments,
-            Some(&value_ranges),
-        );
-    }
+    crate::pretty_clif::write_clif_file(
+        tcx,
+        "opt",
+        Some(cx.module.isa()),
+        instance,
+        &context,
+        &clif_comments,
+    );
 
     // Define debuginfo for function
     let isa = cx.module.isa();
+    let debug_context = &mut cx.debug_context;
     let unwind_context = &mut cx.unwind_context;
     tcx.sess.time("generate debug info", || {
-        debug_context
-            .as_mut()
-            .map(|x| x.define(context, isa, &source_info_set, local_map));
+        if let Some(debug_context) = debug_context {
+            debug_context.define_function(
+                instance,
+                func_id,
+                &name,
+                isa,
+                context,
+                &source_info_set,
+                local_map,
+            );
+        }
         unwind_context.add_function(func_id, &context, isa);
     });
 
@@ -134,14 +157,18 @@ pub(crate) fn trans_fn<'tcx, B: Backend + 'static>(
     context.clear();
 }
 
-pub(crate) fn verify_func(tcx: TyCtxt<'_>, writer: &crate::pretty_clif::CommentWriter, func: &Function) {
+pub(crate) fn verify_func(
+    tcx: TyCtxt<'_>,
+    writer: &crate::pretty_clif::CommentWriter,
+    func: &Function,
+) {
     tcx.sess.time("verify clif ir", || {
-        let flags = settings::Flags::new(settings::builder());
-        match ::cranelift_codegen::verify_function(&func, &flags) {
+        let flags = cranelift_codegen::settings::Flags::new(cranelift_codegen::settings::builder());
+        match cranelift_codegen::verify_function(&func, &flags) {
             Ok(_) => {}
             Err(err) => {
                 tcx.sess.err(&format!("{:?}", err));
-                let pretty_error = ::cranelift_codegen::print_errors::pretty_verifier_error(
+                let pretty_error = cranelift_codegen::print_errors::pretty_verifier_error(
                     &func,
                     None,
                     Some(Box::new(writer)),
@@ -155,6 +182,8 @@ pub(crate) fn verify_func(tcx: TyCtxt<'_>, writer: &crate::pretty_clif::CommentW
 }
 
 fn codegen_fn_content(fx: &mut FunctionCx<'_, '_, impl Backend>) {
+    crate::constant::check_constants(fx);
+
     for (bb, bb_data) in fx.mir.basic_blocks().iter_enumerated() {
         let block = fx.get_block(bb);
         fx.bcx.switch_to_block(block);
@@ -221,7 +250,7 @@ fn codegen_fn_content(fx: &mut FunctionCx<'_, '_, impl Backend>) {
                 cleanup: _,
             } => {
                 if !fx.tcx.sess.overflow_checks() {
-                    if let mir::AssertKind::OverflowNeg = *msg {
+                    if let mir::AssertKind::OverflowNeg(_) = *msg {
                         let target = fx.get_block(*target);
                         fx.bcx.ins().jump(target, &[]);
                         continue;
@@ -242,7 +271,9 @@ fn codegen_fn_content(fx: &mut FunctionCx<'_, '_, impl Backend>) {
 
                 fx.bcx.switch_to_block(failure);
 
-                let location = fx.get_caller_location(bb_data.terminator().source_info.span).load_scalar(fx);
+                let location = fx
+                    .get_caller_location(bb_data.terminator().source_info.span)
+                    .load_scalar(fx);
 
                 let args;
                 let lang_item = match msg {
@@ -250,43 +281,80 @@ fn codegen_fn_content(fx: &mut FunctionCx<'_, '_, impl Backend>) {
                         let len = trans_operand(fx, len).load_scalar(fx);
                         let index = trans_operand(fx, index).load_scalar(fx);
                         args = [index, len, location];
-                        rustc_hir::lang_items::PanicBoundsCheckFnLangItem
+                        rustc_hir::LangItem::PanicBoundsCheck
                     }
                     _ => {
                         let msg_str = msg.description();
                         let msg_ptr = fx.anonymous_str("assert", msg_str);
-                        let msg_len = fx.bcx.ins().iconst(fx.pointer_type, i64::try_from(msg_str.len()).unwrap());
+                        let msg_len = fx
+                            .bcx
+                            .ins()
+                            .iconst(fx.pointer_type, i64::try_from(msg_str.len()).unwrap());
                         args = [msg_ptr, msg_len, location];
-                        rustc_hir::lang_items::PanicFnLangItem
+                        rustc_hir::LangItem::Panic
                     }
                 };
 
                 let def_id = fx.tcx.lang_items().require(lang_item).unwrap_or_else(|s| {
-                    fx.tcx.sess.span_fatal(bb_data.terminator().source_info.span, &s)
+                    fx.tcx
+                        .sess
+                        .span_fatal(bb_data.terminator().source_info.span, &s)
                 });
 
-                let instance = Instance::mono(fx.tcx, def_id);
-                let symbol_name = fx.tcx.symbol_name(instance).name.as_str();
+                let instance = Instance::mono(fx.tcx, def_id).polymorphize(fx.tcx);
+                let symbol_name = fx.tcx.symbol_name(instance).name;
 
-                fx.lib_call(&*symbol_name, vec![fx.pointer_type, fx.pointer_type, fx.pointer_type], vec![], &args);
+                fx.lib_call(
+                    &*symbol_name,
+                    vec![fx.pointer_type, fx.pointer_type, fx.pointer_type],
+                    vec![],
+                    &args,
+                );
 
                 crate::trap::trap_unreachable(fx, "panic lang item returned");
             }
 
             TerminatorKind::SwitchInt {
                 discr,
-                switch_ty: _,
+                switch_ty,
                 values,
                 targets,
             } => {
                 let discr = trans_operand(fx, discr).load_scalar(fx);
-                let mut switch = ::cranelift_frontend::Switch::new();
-                for (i, value) in values.iter().enumerate() {
-                    let block = fx.get_block(targets[i]);
-                    switch.set_entry(*value as u64, block);
+
+                if switch_ty.kind() == fx.tcx.types.bool.kind() {
+                    assert_eq!(targets.len(), 2);
+                    let then_block = fx.get_block(targets[0]);
+                    let else_block = fx.get_block(targets[1]);
+                    let test_zero = match **values {
+                        [0] => true,
+                        [1] => false,
+                        _ => unreachable!("{:?}", values),
+                    };
+
+                    let discr = crate::optimize::peephole::maybe_unwrap_bint(&mut fx.bcx, discr);
+                    let (discr, is_inverted) =
+                        crate::optimize::peephole::maybe_unwrap_bool_not(&mut fx.bcx, discr);
+                    let test_zero = if is_inverted { !test_zero } else { test_zero };
+                    let discr = crate::optimize::peephole::maybe_unwrap_bint(&mut fx.bcx, discr);
+                    let discr =
+                        crate::optimize::peephole::make_branchable_value(&mut fx.bcx, discr);
+                    if test_zero {
+                        fx.bcx.ins().brz(discr, then_block, &[]);
+                        fx.bcx.ins().jump(else_block, &[]);
+                    } else {
+                        fx.bcx.ins().brnz(discr, then_block, &[]);
+                        fx.bcx.ins().jump(else_block, &[]);
+                    }
+                } else {
+                    let mut switch = ::cranelift_frontend::Switch::new();
+                    for (i, value) in values.iter().enumerate() {
+                        let block = fx.get_block(targets[i]);
+                        switch.set_entry(*value, block);
+                    }
+                    let otherwise_block = fx.get_block(targets[targets.len() - 1]);
+                    switch.emit(&mut fx.bcx, discr, otherwise_block);
                 }
-                let otherwise_block = fx.get_block(targets[targets.len() - 1]);
-                switch.emit(&mut fx.bcx, discr, otherwise_block);
             }
             TerminatorKind::Call {
                 func,
@@ -296,36 +364,43 @@ fn codegen_fn_content(fx: &mut FunctionCx<'_, '_, impl Backend>) {
                 cleanup: _,
                 from_hir_call: _,
             } => {
-                fx.tcx.sess.time("codegen call", || crate::abi::codegen_terminator_call(
-                    fx,
-                    *fn_span,
-                    block,
-                    func,
-                    args,
-                    *destination,
-                ));
+                fx.tcx.sess.time("codegen call", || {
+                    crate::abi::codegen_terminator_call(
+                        fx,
+                        *fn_span,
+                        block,
+                        func,
+                        args,
+                        *destination,
+                    )
+                });
             }
             TerminatorKind::InlineAsm {
                 template,
                 operands,
-                options: _,
+                options,
                 destination,
                 line_spans: _,
             } => {
-                match template {
-                    &[] => {
-                        assert_eq!(operands, &[]);
-                        match *destination {
-                            Some(destination) => {
-                                let destination_block = fx.get_block(destination);
-                                fx.bcx.ins().jump(destination_block, &[]);
-                            }
-                            None => bug!(),
-                        }
+                crate::inline_asm::codegen_inline_asm(
+                    fx,
+                    bb_data.terminator().source_info.span,
+                    template,
+                    operands,
+                    *options,
+                );
 
-                        // Black box
+                match *destination {
+                    Some(destination) => {
+                        let destination_block = fx.get_block(destination);
+                        fx.bcx.ins().jump(destination_block, &[]);
+                    }
+                    None => {
+                        crate::trap::trap_unreachable(
+                            fx,
+                            "[corruption] Returned from noreturn inline asm",
+                        );
                     }
-                    _ => unimpl_fatal!(fx.tcx, bb_data.terminator().source_info.span, "Inline assembly is not supported"),
                 }
             }
             TerminatorKind::Resume | TerminatorKind::Abort => {
@@ -342,11 +417,11 @@ fn codegen_fn_content(fx: &mut FunctionCx<'_, '_, impl Backend>) {
                 bug!("shouldn't exist at trans {:?}", bb_data.terminator());
             }
             TerminatorKind::Drop {
-                location,
+                place,
                 target,
                 unwind: _,
             } => {
-                let drop_place = trans_place(fx, *location);
+                let drop_place = trans_place(fx, *place);
                 crate::abi::codegen_drop(fx, bb_data.terminator().source_info.span, drop_place);
 
                 let target_block = fx.get_block(*target);
@@ -361,11 +436,10 @@ fn codegen_fn_content(fx: &mut FunctionCx<'_, '_, impl Backend>) {
 
 fn trans_stmt<'tcx>(
     fx: &mut FunctionCx<'_, 'tcx, impl Backend>,
-    #[allow(unused_variables)]
-    cur_block: Block,
+    #[allow(unused_variables)] cur_block: Block,
     stmt: &Statement<'tcx>,
 ) {
-    let _print_guard = PrintOnPanic(|| format!("stmt {:?}", stmt));
+    let _print_guard = crate::PrintOnPanic(|| format!("stmt {:?}", stmt));
 
     fx.set_debug_loc(stmt.source_info);
 
@@ -396,7 +470,8 @@ fn trans_stmt<'tcx>(
                 }
                 Rvalue::Ref(_, _, place) | Rvalue::AddressOf(_, place) => {
                     let place = trans_place(fx, *place);
-                    place.write_place_ref(fx, lval);
+                    let ref_ = place.place_ref(fx, lval.layout());
+                    lval.write_cvalue(fx, ref_);
                 }
                 Rvalue::ThreadLocalRef(def_id) => {
                     let val = crate::constant::codegen_tls_ref(fx, *def_id, lval.layout());
@@ -429,30 +504,24 @@ fn trans_stmt<'tcx>(
                     let layout = operand.layout();
                     let val = operand.load_scalar(fx);
                     let res = match un_op {
-                        UnOp::Not => {
-                            match layout.ty.kind {
-                                ty::Bool => {
-                                    let res = fx.bcx.ins().icmp_imm(IntCC::Equal, val, 0);
-                                    CValue::by_val(fx.bcx.ins().bint(types::I8, res), layout)
-                                }
-                                ty::Uint(_) | ty::Int(_) => {
-                                    CValue::by_val(fx.bcx.ins().bnot(val), layout)
-                                }
-                                _ => unreachable!("un op Not for {:?}", layout.ty),
+                        UnOp::Not => match layout.ty.kind() {
+                            ty::Bool => {
+                                let res = fx.bcx.ins().icmp_imm(IntCC::Equal, val, 0);
+                                CValue::by_val(fx.bcx.ins().bint(types::I8, res), layout)
                             }
-                        }
-                        UnOp::Neg => match layout.ty.kind {
+                            ty::Uint(_) | ty::Int(_) => {
+                                CValue::by_val(fx.bcx.ins().bnot(val), layout)
+                            }
+                            _ => unreachable!("un op Not for {:?}", layout.ty),
+                        },
+                        UnOp::Neg => match layout.ty.kind() {
                             ty::Int(IntTy::I128) => {
                                 // FIXME remove this case once ineg.i128 works
                                 let zero = CValue::const_val(fx, layout, 0);
                                 crate::num::trans_int_binop(fx, BinOp::Sub, zero, operand)
                             }
-                            ty::Int(_) => {
-                                CValue::by_val(fx.bcx.ins().ineg(val), layout)
-                            }
-                            ty::Float(_) => {
-                                CValue::by_val(fx.bcx.ins().fneg(val), layout)
-                            }
+                            ty::Int(_) => CValue::by_val(fx.bcx.ins().ineg(val), layout),
+                            ty::Float(_) => CValue::by_val(fx.bcx.ins().fneg(val), layout),
                             _ => unreachable!("un op Neg for {:?}", layout.ty),
                         },
                     };
@@ -461,11 +530,17 @@ fn trans_stmt<'tcx>(
                 Rvalue::Cast(CastKind::Pointer(PointerCast::ReifyFnPointer), operand, to_ty) => {
                     let from_ty = fx.monomorphize(&operand.ty(&fx.mir.local_decls, fx.tcx));
                     let to_layout = fx.layout_of(fx.monomorphize(to_ty));
-                    match from_ty.kind {
+                    match *from_ty.kind() {
                         ty::FnDef(def_id, substs) => {
                             let func_ref = fx.get_function_ref(
-                                Instance::resolve_for_fn_ptr(fx.tcx, ParamEnv::reveal_all(), def_id, substs)
-                                    .unwrap(),
+                                Instance::resolve_for_fn_ptr(
+                                    fx.tcx,
+                                    ParamEnv::reveal_all(),
+                                    def_id,
+                                    substs,
+                                )
+                                .unwrap()
+                                .polymorphize(fx.tcx),
                             );
                             let func_addr = fx.bcx.ins().func_addr(fx.pointer_type, func_ref);
                             lval.write_cvalue(fx, CValue::by_val(func_addr, to_layout));
@@ -494,7 +569,9 @@ fn is_fat_ptr<'tcx>(
                                 |ty::TypeAndMut {
                                      ty: pointee_ty,
                                      mutbl: _,
-                                 }| has_ptr_meta(fx.tcx, pointee_ty),
+                                 }| {
+                                    has_ptr_meta(fx.tcx, pointee_ty)
+                                },
                             )
                             .unwrap_or(false)
                     }
@@ -508,20 +585,59 @@ fn is_fat_ptr<'tcx>(
                             let (ptr, _extra) = operand.load_scalar_pair(fx);
                             lval.write_cvalue(fx, CValue::by_val(ptr, dest_layout))
                         }
-                    } else if let ty::Adt(adt_def, _substs) = from_ty.kind {
+                    } else if let ty::Adt(adt_def, _substs) = from_ty.kind() {
                         // enum -> discriminant value
                         assert!(adt_def.is_enum());
-                        match to_ty.kind {
+                        match to_ty.kind() {
                             ty::Uint(_) | ty::Int(_) => {}
                             _ => unreachable!("cast adt {} -> {}", from_ty, to_ty),
                         }
 
-                        let discr = crate::discriminant::codegen_get_discriminant(
-                            fx,
-                            operand,
-                            fx.layout_of(to_ty),
-                        );
-                        lval.write_cvalue(fx, discr);
+                        use rustc_target::abi::{Int, TagEncoding, Variants};
+
+                        match &operand.layout().variants {
+                            Variants::Single { index } => {
+                                let discr = operand
+                                    .layout()
+                                    .ty
+                                    .discriminant_for_variant(fx.tcx, *index)
+                                    .unwrap();
+                                let discr = if discr.ty.is_signed() {
+                                    rustc_middle::mir::interpret::sign_extend(
+                                        discr.val,
+                                        fx.layout_of(discr.ty).size,
+                                    )
+                                } else {
+                                    discr.val
+                                };
+
+                                let discr = CValue::const_val(fx, fx.layout_of(to_ty), discr);
+                                lval.write_cvalue(fx, discr);
+                            }
+                            Variants::Multiple {
+                                tag,
+                                tag_field,
+                                tag_encoding: TagEncoding::Direct,
+                                variants: _,
+                            } => {
+                                let cast_to = fx.clif_type(dest_layout.ty).unwrap();
+
+                                // Read the tag/niche-encoded discriminant from memory.
+                                let encoded_discr =
+                                    operand.value_field(fx, mir::Field::new(*tag_field));
+                                let encoded_discr = encoded_discr.load_scalar(fx);
+
+                                // Decode the discriminant (specifically if it's niche-encoded).
+                                let signed = match tag.value {
+                                    Int(_, signed) => signed,
+                                    _ => false,
+                                };
+                                let val = clif_intcast(fx, encoded_discr, cast_to, signed);
+                                let val = CValue::by_val(val, dest_layout);
+                                lval.write_cvalue(fx, val);
+                            }
+                            Variants::Multiple { .. } => unreachable!(),
+                        }
                     } else {
                         let to_clif_ty = fx.clif_type(to_ty).unwrap();
                         let from = operand.load_scalar(fx);
@@ -536,16 +652,21 @@ fn is_fat_ptr<'tcx>(
                         lval.write_cvalue(fx, CValue::by_val(res, dest_layout));
                     }
                 }
-                Rvalue::Cast(CastKind::Pointer(PointerCast::ClosureFnPointer(_)), operand, _to_ty) => {
+                Rvalue::Cast(
+                    CastKind::Pointer(PointerCast::ClosureFnPointer(_)),
+                    operand,
+                    _to_ty,
+                ) => {
                     let operand = trans_operand(fx, operand);
-                    match operand.layout().ty.kind {
+                    match *operand.layout().ty.kind() {
                         ty::Closure(def_id, substs) => {
                             let instance = Instance::resolve_closure(
                                 fx.tcx,
                                 def_id,
                                 substs,
                                 ty::ClosureKind::FnOnce,
-                            );
+                            )
+                            .polymorphize(fx.tcx);
                             let func_ref = fx.get_function_ref(instance);
                             let func_addr = fx.bcx.ins().func_addr(fx.pointer_type, func_ref);
                             lval.write_cvalue(fx, CValue::by_val(func_addr, lval.layout()));
@@ -572,10 +693,29 @@ fn is_fat_ptr<'tcx>(
                         .val
                         .try_to_bits(fx.tcx.data_layout.pointer_size)
                         .unwrap();
-                    for i in 0..times {
-                        let index = fx.bcx.ins().iconst(fx.pointer_type, i as i64);
+                    if fx.clif_type(operand.layout().ty) == Some(types::I8) {
+                        let times = fx.bcx.ins().iconst(fx.pointer_type, times as i64);
+                        // FIXME use emit_small_memset where possible
+                        let addr = lval.to_ptr().get_addr(fx);
+                        let val = operand.load_scalar(fx);
+                        fx.bcx.call_memset(fx.cx.module.target_config(), addr, val, times);
+                    } else {
+                        let loop_block = fx.bcx.create_block();
+                        let done_block = fx.bcx.create_block();
+                        let index = fx.bcx.append_block_param(loop_block, fx.pointer_type);
+                        let zero = fx.bcx.ins().iconst(fx.pointer_type, 0);
+                        fx.bcx.ins().jump(loop_block, &[zero]);
+
+                        fx.bcx.switch_to_block(loop_block);
                         let to = lval.place_index(fx, index);
                         to.write_cvalue(fx, operand);
+
+                        let index = fx.bcx.ins().iadd_imm(index, 1);
+                        let done = fx.bcx.ins().icmp_imm(IntCC::Equal, index, times as i64);
+                        fx.bcx.ins().brz(done, loop_block, &[index]);
+                        fx.bcx.ins().jump(done_block, &[]);
+
+                        fx.bcx.switch_to_block(done_block);
                     }
                 }
                 Rvalue::Len(place) => {
@@ -585,8 +725,6 @@ fn is_fat_ptr<'tcx>(
                     lval.write_cvalue(fx, CValue::by_val(len, usize_layout));
                 }
                 Rvalue::NullaryOp(NullOp::Box, content_ty) => {
-                    use rustc_hir::lang_items::ExchangeMallocFnLangItem;
-
                     let usize_type = fx.clif_type(fx.tcx.types.usize).unwrap();
                     let content_ty = fx.monomorphize(content_ty);
                     let layout = fx.layout_of(content_ty);
@@ -598,7 +736,11 @@ fn is_fat_ptr<'tcx>(
                     let box_layout = fx.layout_of(fx.tcx.mk_box(content_ty));
 
                     // Allocate space:
-                    let def_id = match fx.tcx.lang_items().require(ExchangeMallocFnLangItem) {
+                    let def_id = match fx
+                        .tcx
+                        .lang_items()
+                        .require(rustc_hir::LangItem::ExchangeMalloc)
+                    {
                         Ok(id) => id,
                         Err(s) => {
                             fx.tcx
@@ -606,7 +748,7 @@ fn is_fat_ptr<'tcx>(
                                 .fatal(&format!("allocation of `{}` {}", box_layout.ty, s));
                         }
                     };
-                    let instance = ty::Instance::mono(fx.tcx, def_id);
+                    let instance = ty::Instance::mono(fx.tcx, def_id).polymorphize(fx.tcx);
                     let func_ref = fx.get_function_ref(instance);
                     let call = fx.bcx.ins().call(func_ref, &[llsize, llalign]);
                     let ptr = fx.bcx.inst_results(call)[0];
@@ -618,7 +760,8 @@ fn is_fat_ptr<'tcx>(
                         .ty
                         .is_sized(fx.tcx.at(stmt.source_info.span), ParamEnv::reveal_all()));
                     let ty_size = fx.layout_of(fx.monomorphize(ty)).size.bytes();
-                    let val = CValue::const_val(fx, fx.layout_of(fx.tcx.types.usize), ty_size.into());
+                    let val =
+                        CValue::const_val(fx, fx.layout_of(fx.tcx.types.usize), ty_size.into());
                     lval.write_cvalue(fx, val);
                 }
                 Rvalue::Aggregate(kind, operands) => match **kind {
@@ -645,34 +788,68 @@ fn is_fat_ptr<'tcx>(
             use rustc_span::symbol::Symbol;
             let LlvmInlineAsm {
                 asm,
-                outputs: _,
-                inputs: _,
+                outputs,
+                inputs,
             } = &**asm;
             let rustc_hir::LlvmInlineAsmInner {
-                asm: asm_code, // Name
-                outputs,       // Vec<Name>
-                inputs,        // Vec<Name>
-                clobbers,      // Vec<Name>
-                volatile,      // bool
-                alignstack,    // bool
-                dialect: _,    // rustc_ast::ast::AsmDialect
+                asm: asm_code,         // Name
+                outputs: output_names, // Vec<LlvmInlineAsmOutput>
+                inputs: input_names,   // Vec<Name>
+                clobbers,              // Vec<Name>
+                volatile,              // bool
+                alignstack,            // bool
+                dialect: _,
                 asm_str_style: _,
             } = asm;
-            match &*asm_code.as_str() {
-                cpuid if cpuid.contains("cpuid") => {
-                    crate::trap::trap_unimplemented(
-                        fx,
-                        "__cpuid_count arch intrinsic is not supported",
+            match asm_code.as_str().trim() {
+                "" => {
+                    // Black box
+                }
+                "mov %rbx, %rsi\n                  cpuid\n                  xchg %rbx, %rsi" => {
+                    assert_eq!(
+                        input_names,
+                        &[Symbol::intern("{eax}"), Symbol::intern("{ecx}")]
                     );
+                    assert_eq!(output_names.len(), 4);
+                    for (i, c) in (&["={eax}", "={esi}", "={ecx}", "={edx}"])
+                        .iter()
+                        .enumerate()
+                    {
+                        assert_eq!(&output_names[i].constraint.as_str(), c);
+                        assert!(!output_names[i].is_rw);
+                        assert!(!output_names[i].is_indirect);
+                    }
+
+                    assert_eq!(clobbers, &[]);
+
+                    assert!(!volatile);
+                    assert!(!alignstack);
+
+                    assert_eq!(inputs.len(), 2);
+                    let leaf = trans_operand(fx, &inputs[0].1).load_scalar(fx); // %eax
+                    let subleaf = trans_operand(fx, &inputs[1].1).load_scalar(fx); // %ecx
+
+                    let (eax, ebx, ecx, edx) =
+                        crate::intrinsics::codegen_cpuid_call(fx, leaf, subleaf);
+
+                    assert_eq!(outputs.len(), 4);
+                    trans_place(fx, outputs[0])
+                        .write_cvalue(fx, CValue::by_val(eax, fx.layout_of(fx.tcx.types.u32)));
+                    trans_place(fx, outputs[1])
+                        .write_cvalue(fx, CValue::by_val(ebx, fx.layout_of(fx.tcx.types.u32)));
+                    trans_place(fx, outputs[2])
+                        .write_cvalue(fx, CValue::by_val(ecx, fx.layout_of(fx.tcx.types.u32)));
+                    trans_place(fx, outputs[3])
+                        .write_cvalue(fx, CValue::by_val(edx, fx.layout_of(fx.tcx.types.u32)));
                 }
                 "xgetbv" => {
-                    assert_eq!(inputs, &[Symbol::intern("{ecx}")]);
+                    assert_eq!(input_names, &[Symbol::intern("{ecx}")]);
 
-                    assert_eq!(outputs.len(), 2);
+                    assert_eq!(output_names.len(), 2);
                     for (i, c) in (&["={eax}", "={edx}"]).iter().enumerate() {
-                        assert_eq!(&outputs[i].constraint.as_str(), c);
-                        assert!(!outputs[i].is_rw);
-                        assert!(!outputs[i].is_indirect);
+                        assert_eq!(&output_names[i].constraint.as_str(), c);
+                        assert!(!output_names[i].is_rw);
+                        assert!(!output_names[i].is_indirect);
                     }
 
                     assert_eq!(clobbers, &[]);
@@ -682,9 +859,29 @@ fn is_fat_ptr<'tcx>(
 
                     crate::trap::trap_unimplemented(fx, "_xgetbv arch intrinsic is not supported");
                 }
-                _ => unimpl_fatal!(fx.tcx, stmt.source_info.span, "Inline assembly is not supported"),
+                // ___chkstk, ___chkstk_ms and __alloca are only used on Windows
+                _ if fx
+                    .tcx
+                    .symbol_name(fx.instance)
+                    .name
+                    .starts_with("___chkstk") =>
+                {
+                    crate::trap::trap_unimplemented(fx, "Stack probes are not supported");
+                }
+                _ if fx.tcx.symbol_name(fx.instance).name == "__alloca" => {
+                    crate::trap::trap_unimplemented(fx, "Alloca is not supported");
+                }
+                // Used in sys::windows::abort_internal
+                "int $$0x29" => {
+                    crate::trap::trap_unimplemented(fx, "Windows abort");
+                }
+                _ => fx
+                    .tcx
+                    .sess
+                    .span_fatal(stmt.source_info.span, "Inline assembly is not supported"),
             }
         }
+        StatementKind::Coverage { .. } => fx.tcx.sess.fatal("-Zcoverage is unimplemented"),
     }
 }
 
@@ -692,9 +889,10 @@ fn codegen_array_len<'tcx>(
     fx: &mut FunctionCx<'_, 'tcx, impl Backend>,
     place: CPlace<'tcx>,
 ) -> Value {
-    match place.layout().ty.kind {
+    match *place.layout().ty.kind() {
         ty::Array(_elem_ty, len) => {
-            let len = fx.monomorphize(&len)
+            let len = fx
+                .monomorphize(&len)
                 .eval(fx.tcx, ParamEnv::reveal_all())
                 .eval_usize(fx.tcx, ParamEnv::reveal_all()) as i64;
             fx.bcx.ins().iconst(fx.pointer_type, len)
@@ -730,6 +928,7 @@ pub(crate) fn trans_place<'tcx>(
                 min_length: _,
                 from_end,
             } => {
+                let offset: u64 = offset;
                 let index = if !from_end {
                     fx.bcx.ins().iconst(fx.pointer_type, offset as i64)
                 } else {
@@ -742,14 +941,17 @@ pub(crate) fn trans_place<'tcx>(
                 // These indices are generated by slice patterns.
                 // slice[from:-to] in Python terms.
 
-                match cplace.layout().ty.kind {
+                let from: u64 = from;
+                let to: u64 = to;
+
+                match cplace.layout().ty.kind() {
                     ty::Array(elem_ty, _len) => {
                         assert!(!from_end, "array subslices are never `from_end`");
                         let elem_layout = fx.layout_of(elem_ty);
                         let ptr = cplace.to_ptr();
                         cplace = CPlace::for_ptr(
-                            ptr.offset_i64(fx, elem_layout.size.bytes() as i64 * from as i64),
-                            fx.layout_of(fx.tcx.mk_array(elem_ty, to as u64 - from as u64)),
+                            ptr.offset_i64(fx, elem_layout.size.bytes() as i64 * (from as i64)),
+                            fx.layout_of(fx.tcx.mk_array(elem_ty, u64::from(to) - u64::from(from))),
                         );
                     }
                     ty::Slice(elem_ty) => {
@@ -758,7 +960,7 @@ pub(crate) fn trans_place<'tcx>(
                         let (ptr, len) = cplace.to_ptr_maybe_unsized();
                         let len = len.unwrap();
                         cplace = CPlace::for_ptr_with_extra(
-                            ptr.offset_i64(fx, elem_layout.size.bytes() as i64 * from as i64),
+                            ptr.offset_i64(fx, elem_layout.size.bytes() as i64 * (from as i64)),
                             fx.bcx.ins().iadd_imm(len, -(from as i64 + to as i64)),
                             cplace.layout(),
                         );