From 6ceb1637b2500f384015578a5a6f556bcc992052 Mon Sep 17 00:00:00 2001
From: bjorn3 <bjorn3@users.noreply.github.com>
Date: Fri, 15 Jun 2018 19:02:41 +0200
Subject: [PATCH 01/19] Move some functions out of rustc_codegen_llvm and fix
 metadata_only backend

---
 src/bootstrap/bin/rustc.rs                    |   4 +
 src/bootstrap/compile.rs                      |  16 ++-
 src/librustc_codegen_llvm/base.rs             |   7 +-
 src/librustc_codegen_llvm/common.rs           | 104 ++++++++++++++-
 src/librustc_codegen_llvm/lib.rs              |   4 +-
 src/librustc_codegen_llvm/llvm_util.rs        | 118 +-----------------
 src/librustc_codegen_llvm/mono_item.rs        |   2 +-
 src/librustc_codegen_utils/codegen_backend.rs |  16 ++-
 src/librustc_codegen_utils/lib.rs             |   2 +
 .../llvm_target_features.rs                   | 117 +++++++++++++++++
 .../time_graph.rs                             |   0
 src/librustc_driver/lib.rs                    |  14 ++-
 12 files changed, 265 insertions(+), 139 deletions(-)
 create mode 100644 src/librustc_codegen_utils/llvm_target_features.rs
 rename src/{librustc_codegen_llvm => librustc_codegen_utils}/time_graph.rs (100%)

diff --git a/src/bootstrap/bin/rustc.rs b/src/bootstrap/bin/rustc.rs
index 4607ca5cf9f4..d38ffe431e04 100644
--- a/src/bootstrap/bin/rustc.rs
+++ b/src/bootstrap/bin/rustc.rs
@@ -114,6 +114,10 @@ fn main() {
 
     cmd.env("RUSTC_BREAK_ON_ICE", "1");
 
+    if args.iter().find(|s| **s == OsString::from("___")).is_some() {
+        cmd.arg("-Zcodegen-backend=metadata_only");
+    }
+
     if let Some(target) = target {
         // The stage0 compiler has a special sysroot distinct from what we
         // actually downloaded, so we just always pass the `--sysroot` option.
diff --git a/src/bootstrap/compile.rs b/src/bootstrap/compile.rs
index 298bd58c6cdf..e23566d52f0b 100644
--- a/src/bootstrap/compile.rs
+++ b/src/bootstrap/compile.rs
@@ -182,11 +182,13 @@ pub fn std_cargo(builder: &Builder,
             // missing
             // We also only build the runtimes when --enable-sanitizers (or its
             // config.toml equivalent) is used
-            let llvm_config = builder.ensure(native::Llvm {
-                target: builder.config.build,
-                emscripten: false,
-            });
-            cargo.env("LLVM_CONFIG", llvm_config);
+            if !builder.config.rust_codegen_backends.is_empty() {
+                let llvm_config = builder.ensure(native::Llvm {
+                    target: builder.config.build,
+                    emscripten: false,
+                });
+                cargo.env("LLVM_CONFIG", llvm_config);
+            }
         }
 
         cargo.arg("--features").arg(features)
@@ -675,7 +677,9 @@ impl Step for CodegenBackend {
             .arg(builder.src.join("src/librustc_codegen_llvm/Cargo.toml"));
         rustc_cargo_env(builder, &mut cargo);
 
-        features += &build_codegen_backend(&builder, &mut cargo, &compiler, target, backend);
+        if !backend.is_empty() {
+            features += &build_codegen_backend(&builder, &mut cargo, &compiler, target, backend);
+        }
 
         let tmp_stamp = builder.cargo_out(compiler, Mode::Codegen, target)
             .join(".tmp.stamp");
diff --git a/src/librustc_codegen_llvm/base.rs b/src/librustc_codegen_llvm/base.rs
index a4709739a23d..53c70eb42ce5 100644
--- a/src/librustc_codegen_llvm/base.rs
+++ b/src/librustc_codegen_llvm/base.rs
@@ -56,6 +56,7 @@ use builder::{Builder, MemFlags};
 use callee;
 use common::{C_bool, C_bytes_in_context, C_i32, C_usize};
 use rustc_mir::monomorphize::collector::{self, MonoItemCollectionMode};
+use rustc_mir::monomorphize::item::DefPathBasedNames;
 use common::{self, C_struct_in_context, C_array, val_ty};
 use consts;
 use context::{self, CodegenCx};
@@ -67,7 +68,7 @@ use monomorphize::Instance;
 use monomorphize::partitioning::{self, PartitioningStrategy, CodegenUnit, CodegenUnitExt};
 use rustc_codegen_utils::symbol_names_test;
 use time_graph;
-use mono_item::{MonoItem, BaseMonoItemExt, MonoItemExt, DefPathBasedNames};
+use mono_item::{MonoItem, BaseMonoItemExt, MonoItemExt};
 use type_::Type;
 use type_of::LayoutLlvmExt;
 use rustc::util::nodemap::{FxHashMap, FxHashSet, DefIdSet};
@@ -92,8 +93,6 @@ use syntax::ast;
 
 use mir::operand::OperandValue;
 
-pub use rustc_codegen_utils::check_for_rustc_errors_attr;
-
 pub struct StatRecorder<'a, 'tcx: 'a> {
     cx: &'a CodegenCx<'a, 'tcx>,
     name: Option<String>,
@@ -715,7 +714,7 @@ pub fn codegen_crate<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                              rx: mpsc::Receiver<Box<Any + Send>>)
                              -> OngoingCodegen {
 
-    check_for_rustc_errors_attr(tcx);
+    ::rustc_codegen_utils::check_for_rustc_errors_attr(tcx);
 
     if let Some(true) = tcx.sess.opts.debugging_opts.thinlto {
         if unsafe { !llvm::LLVMRustThinLTOAvailable() } {
diff --git a/src/librustc_codegen_llvm/common.rs b/src/librustc_codegen_llvm/common.rs
index 7e55642814bb..099d717e3c00 100644
--- a/src/librustc_codegen_llvm/common.rs
+++ b/src/librustc_codegen_llvm/common.rs
@@ -12,9 +12,7 @@
 
 //! Code that is useful in various codegen modules.
 
-use llvm;
-use llvm::{ValueRef, ContextRef, TypeKind};
-use llvm::{True, False, Bool, OperandBundleDef};
+use llvm::{self, ValueRef, ContextRef, TypeKind, True, False, Bool, OperandBundleDef};
 use rustc::hir::def_id::DefId;
 use rustc::middle::lang_items::LangItem;
 use abi;
@@ -29,6 +27,8 @@ use rustc::ty::{self, Ty, TyCtxt};
 use rustc::ty::layout::{HasDataLayout, LayoutOf};
 use rustc::hir;
 
+use meth;
+
 use libc::{c_uint, c_char};
 use std::iter;
 
@@ -448,3 +448,101 @@ pub fn ty_fn_sig<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
         _ => bug!("unexpected type {:?} to ty_fn_sig", ty)
     }
 }
+
+pub fn size_and_align_of_dst<'a, 'tcx>(bx: &Builder<'a, 'tcx>, t: Ty<'tcx>, info: ValueRef)
+                                       -> (ValueRef, ValueRef) {
+    debug!("calculate size of DST: {}; with lost info: {:?}",
+           t, Value(info));
+    if bx.cx.type_is_sized(t) {
+        let (size, align) = bx.cx.size_and_align_of(t);
+        debug!("size_and_align_of_dst t={} info={:?} size: {:?} align: {:?}",
+               t, Value(info), size, align);
+        let size = C_usize(bx.cx, size.bytes());
+        let align = C_usize(bx.cx, align.abi());
+        return (size, align);
+    }
+    assert!(!info.is_null());
+    match t.sty {
+        ty::TyDynamic(..) => {
+            // load size/align from vtable
+            (meth::SIZE.get_usize(bx, info), meth::ALIGN.get_usize(bx, info))
+        }
+        ty::TySlice(_) | ty::TyStr => {
+            let unit = t.sequence_element_type(bx.tcx());
+            // The info in this case is the length of the str, so the size is that
+            // times the unit size.
+            let (size, align) = bx.cx.size_and_align_of(unit);
+            (bx.mul(info, C_usize(bx.cx, size.bytes())),
+             C_usize(bx.cx, align.abi()))
+        }
+        _ => {
+            let cx = bx.cx;
+            // First get the size of all statically known fields.
+            // Don't use size_of because it also rounds up to alignment, which we
+            // want to avoid, as the unsized field's alignment could be smaller.
+            assert!(!t.is_simd());
+            let layout = cx.layout_of(t);
+            debug!("DST {} layout: {:?}", t, layout);
+
+            let i = layout.fields.count() - 1;
+            let sized_size = layout.fields.offset(i).bytes();
+            let sized_align = layout.align.abi();
+            debug!("DST {} statically sized prefix size: {} align: {}",
+                   t, sized_size, sized_align);
+            let sized_size = C_usize(cx, sized_size);
+            let sized_align = C_usize(cx, sized_align);
+
+            // Recurse to get the size of the dynamically sized field (must be
+            // the last field).
+            let field_ty = layout.field(cx, i).ty;
+            let (unsized_size, mut unsized_align) = size_and_align_of_dst(bx, field_ty, info);
+
+            // FIXME (#26403, #27023): We should be adding padding
+            // to `sized_size` (to accommodate the `unsized_align`
+            // required of the unsized field that follows) before
+            // summing it with `sized_size`. (Note that since #26403
+            // is unfixed, we do not yet add the necessary padding
+            // here. But this is where the add would go.)
+
+            // Return the sum of sizes and max of aligns.
+            let size = bx.add(sized_size, unsized_size);
+
+            // Packed types ignore the alignment of their fields.
+            if let ty::TyAdt(def, _) = t.sty {
+                if def.repr.packed() {
+                    unsized_align = sized_align;
+                }
+            }
+
+            // Choose max of two known alignments (combined value must
+            // be aligned according to more restrictive of the two).
+            let align = match (const_to_opt_u128(sized_align, false),
+                               const_to_opt_u128(unsized_align, false)) {
+                (Some(sized_align), Some(unsized_align)) => {
+                    // If both alignments are constant, (the sized_align should always be), then
+                    // pick the correct alignment statically.
+                    C_usize(cx, ::std::cmp::max(sized_align, unsized_align) as u64)
+                }
+                _ => bx.select(bx.icmp(llvm::IntUGT, sized_align, unsized_align),
+                                sized_align,
+                                unsized_align)
+            };
+
+            // Issue #27023: must add any necessary padding to `size`
+            // (to make it a multiple of `align`) before returning it.
+            //
+            // Namely, the returned size should be, in C notation:
+            //
+            //   `size + ((size & (align-1)) ? align : 0)`
+            //
+            // emulated via the semi-standard fast bit trick:
+            //
+            //   `(size + (align-1)) & -align`
+
+            let addend = bx.sub(align, C_usize(bx.cx, 1));
+            let size = bx.and(bx.add(size, addend), bx.neg(align));
+
+            (size, align)
+        }
+    }
+}
diff --git a/src/librustc_codegen_llvm/lib.rs b/src/librustc_codegen_llvm/lib.rs
index b11b0c7abe87..eee4e5f8f7a0 100644
--- a/src/librustc_codegen_llvm/lib.rs
+++ b/src/librustc_codegen_llvm/lib.rs
@@ -79,6 +79,7 @@ use rustc::ty::{self, TyCtxt};
 use rustc::util::nodemap::{FxHashSet, FxHashMap};
 use rustc_mir::monomorphize;
 use rustc_codegen_utils::codegen_backend::CodegenBackend;
+use rustc_codegen_utils::time_graph;
 
 mod diagnostics;
 
@@ -114,7 +115,6 @@ mod llvm_util;
 mod metadata;
 mod meth;
 mod mir;
-mod time_graph;
 mod mono_item;
 mod type_;
 mod type_of;
@@ -368,7 +368,7 @@ struct CodegenResults {
     crate_info: CrateInfo,
 }
 
-// Misc info we load from metadata to persist beyond the tcx
+/// Misc info we load from metadata to persist beyond the tcx
 struct CrateInfo {
     panic_runtime: Option<CrateNum>,
     compiler_builtins: Option<CrateNum>,
diff --git a/src/librustc_codegen_llvm/llvm_util.rs b/src/librustc_codegen_llvm/llvm_util.rs
index 87ee9ef5adb2..b63b43c9c73a 100644
--- a/src/librustc_codegen_llvm/llvm_util.rs
+++ b/src/librustc_codegen_llvm/llvm_util.rs
@@ -20,6 +20,8 @@ use syntax::feature_gate::UnstableFeatures;
 use std::sync::atomic::{AtomicBool, Ordering};
 use std::sync::Once;
 
+pub use rustc_codegen_utils::llvm_target_features::*;
+
 static POISONED: AtomicBool = AtomicBool::new(false);
 static INIT: Once = Once::new();
 
@@ -79,108 +81,6 @@ unsafe fn configure_llvm(sess: &Session) {
                                  llvm_args.as_ptr());
 }
 
-// WARNING: the features after applying `to_llvm_feature` must be known
-// to LLVM or the feature detection code will walk past the end of the feature
-// array, leading to crashes.
-
-const ARM_WHITELIST: &[(&str, Option<&str>)] = &[
-    ("mclass", Some("arm_target_feature")),
-    ("neon", Some("arm_target_feature")),
-    ("v7", Some("arm_target_feature")),
-    ("vfp2", Some("arm_target_feature")),
-    ("vfp3", Some("arm_target_feature")),
-    ("vfp4", Some("arm_target_feature")),
-];
-
-const AARCH64_WHITELIST: &[(&str, Option<&str>)] = &[
-    ("fp", Some("aarch64_target_feature")),
-    ("neon", Some("aarch64_target_feature")),
-    ("sve", Some("aarch64_target_feature")),
-    ("crc", Some("aarch64_target_feature")),
-    ("crypto", Some("aarch64_target_feature")),
-    ("ras", Some("aarch64_target_feature")),
-    ("lse", Some("aarch64_target_feature")),
-    ("rdm", Some("aarch64_target_feature")),
-    ("fp16", Some("aarch64_target_feature")),
-    ("rcpc", Some("aarch64_target_feature")),
-    ("dotprod", Some("aarch64_target_feature")),
-    ("v8.1a", Some("aarch64_target_feature")),
-    ("v8.2a", Some("aarch64_target_feature")),
-    ("v8.3a", Some("aarch64_target_feature")),
-];
-
-const X86_WHITELIST: &[(&str, Option<&str>)] = &[
-    ("aes", None),
-    ("avx", None),
-    ("avx2", None),
-    ("avx512bw", Some("avx512_target_feature")),
-    ("avx512cd", Some("avx512_target_feature")),
-    ("avx512dq", Some("avx512_target_feature")),
-    ("avx512er", Some("avx512_target_feature")),
-    ("avx512f", Some("avx512_target_feature")),
-    ("avx512ifma", Some("avx512_target_feature")),
-    ("avx512pf", Some("avx512_target_feature")),
-    ("avx512vbmi", Some("avx512_target_feature")),
-    ("avx512vl", Some("avx512_target_feature")),
-    ("avx512vpopcntdq", Some("avx512_target_feature")),
-    ("bmi1", None),
-    ("bmi2", None),
-    ("fma", None),
-    ("fxsr", None),
-    ("lzcnt", None),
-    ("mmx", Some("mmx_target_feature")),
-    ("pclmulqdq", None),
-    ("popcnt", None),
-    ("rdrand", None),
-    ("rdseed", None),
-    ("sha", None),
-    ("sse", None),
-    ("sse2", None),
-    ("sse3", None),
-    ("sse4.1", None),
-    ("sse4.2", None),
-    ("sse4a", Some("sse4a_target_feature")),
-    ("ssse3", None),
-    ("tbm", Some("tbm_target_feature")),
-    ("xsave", None),
-    ("xsavec", None),
-    ("xsaveopt", None),
-    ("xsaves", None),
-];
-
-const HEXAGON_WHITELIST: &[(&str, Option<&str>)] = &[
-    ("hvx", Some("hexagon_target_feature")),
-    ("hvx-double", Some("hexagon_target_feature")),
-];
-
-const POWERPC_WHITELIST: &[(&str, Option<&str>)] = &[
-    ("altivec", Some("powerpc_target_feature")),
-    ("power8-altivec", Some("powerpc_target_feature")),
-    ("power9-altivec", Some("powerpc_target_feature")),
-    ("power8-vector", Some("powerpc_target_feature")),
-    ("power9-vector", Some("powerpc_target_feature")),
-    ("vsx", Some("powerpc_target_feature")),
-];
-
-const MIPS_WHITELIST: &[(&str, Option<&str>)] = &[
-    ("fp64", Some("mips_target_feature")),
-    ("msa", Some("mips_target_feature")),
-];
-
-/// When rustdoc is running, provide a list of all known features so that all their respective
-/// primtives may be documented.
-///
-/// IMPORTANT: If you're adding another whitelist to the above lists, make sure to add it to this
-/// iterator!
-pub fn all_known_features() -> impl Iterator<Item=(&'static str, Option<&'static str>)> {
-    ARM_WHITELIST.iter().cloned()
-        .chain(AARCH64_WHITELIST.iter().cloned())
-        .chain(X86_WHITELIST.iter().cloned())
-        .chain(HEXAGON_WHITELIST.iter().cloned())
-        .chain(POWERPC_WHITELIST.iter().cloned())
-        .chain(MIPS_WHITELIST.iter().cloned())
-}
-
 pub fn to_llvm_feature<'a>(sess: &Session, s: &'a str) -> &'a str {
     let arch = if sess.target.target.arch == "x86_64" {
         "x86"
@@ -216,20 +116,6 @@ pub fn target_features(sess: &Session) -> Vec<Symbol> {
         .map(|feature| Symbol::intern(feature)).collect()
 }
 
-pub fn target_feature_whitelist(sess: &Session)
-    -> &'static [(&'static str, Option<&'static str>)]
-{
-    match &*sess.target.target.arch {
-        "arm" => ARM_WHITELIST,
-        "aarch64" => AARCH64_WHITELIST,
-        "x86" | "x86_64" => X86_WHITELIST,
-        "hexagon" => HEXAGON_WHITELIST,
-        "mips" | "mips64" => MIPS_WHITELIST,
-        "powerpc" | "powerpc64" => POWERPC_WHITELIST,
-        _ => &[],
-    }
-}
-
 pub fn print_version() {
     // Can be called without initializing LLVM
     unsafe {
diff --git a/src/librustc_codegen_llvm/mono_item.rs b/src/librustc_codegen_llvm/mono_item.rs
index c4a23ac653ca..61f4bc3e6bc8 100644
--- a/src/librustc_codegen_llvm/mono_item.rs
+++ b/src/librustc_codegen_llvm/mono_item.rs
@@ -33,7 +33,7 @@ use std::fmt;
 
 pub use rustc::mir::mono::MonoItem;
 
-pub use rustc_mir::monomorphize::item::*;
+use rustc_mir::monomorphize::item::*;
 pub use rustc_mir::monomorphize::item::MonoItemExt as BaseMonoItemExt;
 
 pub trait MonoItemExt<'a, 'tcx>: fmt::Debug + BaseMonoItemExt<'a, 'tcx> {
diff --git a/src/librustc_codegen_utils/codegen_backend.rs b/src/librustc_codegen_utils/codegen_backend.rs
index 8ba6f30cf16e..8b52d61fd9e5 100644
--- a/src/librustc_codegen_utils/codegen_backend.rs
+++ b/src/librustc_codegen_utils/codegen_backend.rs
@@ -26,7 +26,7 @@ use std::io::prelude::*;
 use std::io::{self, Cursor};
 use std::fs::File;
 use std::path::Path;
-use std::sync::mpsc;
+use std::sync::{mpsc, Arc};
 
 use rustc_data_structures::owning_ref::OwningRef;
 use rustc_data_structures::sync::Lrc;
@@ -44,7 +44,6 @@ use rustc::middle::cstore::EncodedMetadata;
 use rustc::middle::cstore::MetadataLoader;
 use rustc::dep_graph::DepGraph;
 use rustc_target::spec::Target;
-use rustc_data_structures::fx::FxHashMap;
 use rustc_mir::monomorphize::collector;
 use link::{build_link_meta, out_filename};
 
@@ -203,10 +202,17 @@ impl CodegenBackend for MetadataOnlyCodegenBackend {
         ::symbol_names::provide(providers);
 
         providers.target_features_whitelist = |_tcx, _cnum| {
-            Lrc::new(FxHashMap()) // Just a dummy
+            Lrc::new(::llvm_target_features::all_known_features()
+                .map(|(a, b)| (a.to_string(), b.map(|s| s.to_string())))
+                .collect())
         };
+        providers.is_reachable_non_generic = |_tcx, _defid| true;
+        providers.exported_symbols = |_tcx, _crate| Arc::new(Vec::new());
+        providers.wasm_custom_sections = |_tcx, _crate| Lrc::new(Vec::new());
+    }
+    fn provide_extern(&self, providers: &mut Providers) {
+        providers.is_reachable_non_generic = |_tcx, _defid| true;
     }
-    fn provide_extern(&self, _providers: &mut Providers) {}
 
     fn codegen_crate<'a, 'tcx>(
         &self,
@@ -225,7 +231,7 @@ impl CodegenBackend for MetadataOnlyCodegenBackend {
                 collector::MonoItemCollectionMode::Eager
             ).0.iter()
         );
-        ::rustc::middle::dependency_format::calculate(tcx);
+        //::rustc::middle::dependency_format::calculate(tcx);
         let _ = tcx.link_args(LOCAL_CRATE);
         let _ = tcx.native_libraries(LOCAL_CRATE);
         for mono_item in
diff --git a/src/librustc_codegen_utils/lib.rs b/src/librustc_codegen_utils/lib.rs
index d09e8f4845e5..058e4b7841f5 100644
--- a/src/librustc_codegen_utils/lib.rs
+++ b/src/librustc_codegen_utils/lib.rs
@@ -47,6 +47,8 @@ pub mod link;
 pub mod codegen_backend;
 pub mod symbol_names;
 pub mod symbol_names_test;
+pub mod time_graph;
+pub mod llvm_target_features;
 
 /// check for the #[rustc_error] annotation, which forces an
 /// error in codegen. This is used to write compile-fail tests
diff --git a/src/librustc_codegen_utils/llvm_target_features.rs b/src/librustc_codegen_utils/llvm_target_features.rs
new file mode 100644
index 000000000000..82cd397be232
--- /dev/null
+++ b/src/librustc_codegen_utils/llvm_target_features.rs
@@ -0,0 +1,117 @@
+use rustc::session::Session;
+
+// WARNING: the features after applying `to_llvm_feature` must be known
+// to LLVM or the feature detection code will walk past the end of the feature
+// array, leading to crashes.
+
+const ARM_WHITELIST: &[(&str, Option<&str>)] = &[
+    ("mclass", Some("arm_target_feature")),
+    ("neon", Some("arm_target_feature")),
+    ("v7", Some("arm_target_feature")),
+    ("vfp2", Some("arm_target_feature")),
+    ("vfp3", Some("arm_target_feature")),
+    ("vfp4", Some("arm_target_feature")),
+];
+
+const AARCH64_WHITELIST: &[(&str, Option<&str>)] = &[
+    ("fp", Some("aarch64_target_feature")),
+    ("neon", Some("aarch64_target_feature")),
+    ("sve", Some("aarch64_target_feature")),
+    ("crc", Some("aarch64_target_feature")),
+    ("crypto", Some("aarch64_target_feature")),
+    ("ras", Some("aarch64_target_feature")),
+    ("lse", Some("aarch64_target_feature")),
+    ("rdm", Some("aarch64_target_feature")),
+    ("fp16", Some("aarch64_target_feature")),
+    ("rcpc", Some("aarch64_target_feature")),
+    ("dotprod", Some("aarch64_target_feature")),
+    ("v8.1a", Some("aarch64_target_feature")),
+    ("v8.2a", Some("aarch64_target_feature")),
+    ("v8.3a", Some("aarch64_target_feature")),
+];
+
+const X86_WHITELIST: &[(&str, Option<&str>)] = &[
+    ("aes", None),
+    ("avx", None),
+    ("avx2", None),
+    ("avx512bw", Some("avx512_target_feature")),
+    ("avx512cd", Some("avx512_target_feature")),
+    ("avx512dq", Some("avx512_target_feature")),
+    ("avx512er", Some("avx512_target_feature")),
+    ("avx512f", Some("avx512_target_feature")),
+    ("avx512ifma", Some("avx512_target_feature")),
+    ("avx512pf", Some("avx512_target_feature")),
+    ("avx512vbmi", Some("avx512_target_feature")),
+    ("avx512vl", Some("avx512_target_feature")),
+    ("avx512vpopcntdq", Some("avx512_target_feature")),
+    ("bmi1", None),
+    ("bmi2", None),
+    ("fma", None),
+    ("fxsr", None),
+    ("lzcnt", None),
+    ("mmx", Some("mmx_target_feature")),
+    ("pclmulqdq", None),
+    ("popcnt", None),
+    ("rdrand", None),
+    ("rdseed", None),
+    ("sha", None),
+    ("sse", None),
+    ("sse2", None),
+    ("sse3", None),
+    ("sse4.1", None),
+    ("sse4.2", None),
+    ("sse4a", Some("sse4a_target_feature")),
+    ("ssse3", None),
+    ("tbm", Some("tbm_target_feature")),
+    ("xsave", None),
+    ("xsavec", None),
+    ("xsaveopt", None),
+    ("xsaves", None),
+];
+
+const HEXAGON_WHITELIST: &[(&str, Option<&str>)] = &[
+    ("hvx", Some("hexagon_target_feature")),
+    ("hvx-double", Some("hexagon_target_feature")),
+];
+
+const POWERPC_WHITELIST: &[(&str, Option<&str>)] = &[
+    ("altivec", Some("powerpc_target_feature")),
+    ("power8-altivec", Some("powerpc_target_feature")),
+    ("power9-altivec", Some("powerpc_target_feature")),
+    ("power8-vector", Some("powerpc_target_feature")),
+    ("power9-vector", Some("powerpc_target_feature")),
+    ("vsx", Some("powerpc_target_feature")),
+];
+
+const MIPS_WHITELIST: &[(&str, Option<&str>)] = &[
+    ("fp64", Some("mips_target_feature")),
+    ("msa", Some("mips_target_feature")),
+];
+
+/// When rustdoc is running, provide a list of all known features so that all their respective
+/// primtives may be documented.
+///
+/// IMPORTANT: If you're adding another whitelist to the above lists, make sure to add it to this
+/// iterator!
+pub fn all_known_features() -> impl Iterator<Item=(&'static str, Option<&'static str>)> {
+    ARM_WHITELIST.iter().cloned()
+        .chain(AARCH64_WHITELIST.iter().cloned())
+        .chain(X86_WHITELIST.iter().cloned())
+        .chain(HEXAGON_WHITELIST.iter().cloned())
+        .chain(POWERPC_WHITELIST.iter().cloned())
+        .chain(MIPS_WHITELIST.iter().cloned())
+}
+
+pub fn target_feature_whitelist(sess: &Session)
+    -> &'static [(&'static str, Option<&'static str>)]
+{
+    match &*sess.target.target.arch {
+        "arm" => ARM_WHITELIST,
+        "aarch64" => AARCH64_WHITELIST,
+        "x86" | "x86_64" => X86_WHITELIST,
+        "hexagon" => HEXAGON_WHITELIST,
+        "mips" | "mips64" => MIPS_WHITELIST,
+        "powerpc" | "powerpc64" => POWERPC_WHITELIST,
+        _ => &[],
+    }
+}
diff --git a/src/librustc_codegen_llvm/time_graph.rs b/src/librustc_codegen_utils/time_graph.rs
similarity index 100%
rename from src/librustc_codegen_llvm/time_graph.rs
rename to src/librustc_codegen_utils/time_graph.rs
diff --git a/src/librustc_driver/lib.rs b/src/librustc_driver/lib.rs
index 84f7b35d21f3..321d398b5210 100644
--- a/src/librustc_driver/lib.rs
+++ b/src/librustc_driver/lib.rs
@@ -375,10 +375,20 @@ fn get_codegen_sysroot(backend_name: &str) -> fn() -> Box<CodegenBackend> {
     match file {
         Some(ref s) => return load_backend_from_dylib(s),
         None => {
-            let err = format!("failed to load default codegen backend for `{}`, \
+            if !::rustc::session::config::nightly_options::is_nightly_build() {
+                let err = format!("failed to load default codegen backend for `{}`, \
                                no appropriate codegen dylib found in `{}`",
                                backend_name, sysroot.display());
-            early_error(ErrorOutputType::default(), &err);
+                early_error(ErrorOutputType::default(), &err);
+            } else {
+                let warn = format!("no codegen-backend `{}`, \
+                               no appropriate dylib in `{}`. \
+                               Falling back to metadata_only codegen backend. \
+                               **This is suitable for dev purposes only**",
+                               backend_name, sysroot.display());
+                early_warn(ErrorOutputType::default(), &warn);
+                return rustc_codegen_utils::codegen_backend::MetadataOnlyCodegenBackend::new;
+            }
         }
     }
 

From 95ed511514ea46ae50ce06e9e19c5460a786838a Mon Sep 17 00:00:00 2001
From: bjorn3 <bjorn3@users.noreply.github.com>
Date: Sat, 16 Jun 2018 11:45:59 +0200
Subject: [PATCH 02/19] Mostly fix compiling without LLVM (with metadata_only
 backend)

---
 config.toml.example                           |   4 -
 src/Cargo.lock                                |   2 -
 src/bootstrap/bin/rustc.rs                    |   4 -
 src/bootstrap/builder.rs                      |   2 +-
 src/bootstrap/config.rs                       |   4 -
 src/bootstrap/test.rs                         |   4 +-
 src/bootstrap/tool.rs                         |   2 +-
 src/librustc_codegen_utils/Cargo.toml         |   2 -
 src/librustc_codegen_utils/codegen_backend.rs | 105 ++----------------
 src/librustc_codegen_utils/lib.rs             |   4 -
 src/tools/tidy/src/deps.rs                    |   1 -
 11 files changed, 15 insertions(+), 119 deletions(-)

diff --git a/config.toml.example b/config.toml.example
index 0578f929224d..7bf52a369e37 100644
--- a/config.toml.example
+++ b/config.toml.example
@@ -14,10 +14,6 @@
 # =============================================================================
 [llvm]
 
-# Indicates whether rustc will support compilation with LLVM
-# note: rustc does not compile without LLVM at the moment
-#enabled = true
-
 # Indicates whether the LLVM build is a Release or Debug build
 #optimize = true
 
diff --git a/src/Cargo.lock b/src/Cargo.lock
index 7297d8a8299a..e3610c1d679b 100644
--- a/src/Cargo.lock
+++ b/src/Cargo.lock
@@ -2031,8 +2031,6 @@ dependencies = [
 name = "rustc_codegen_utils"
 version = "0.0.0"
 dependencies = [
- "ar 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "flate2 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc 0.0.0",
  "rustc_data_structures 0.0.0",
diff --git a/src/bootstrap/bin/rustc.rs b/src/bootstrap/bin/rustc.rs
index d38ffe431e04..4607ca5cf9f4 100644
--- a/src/bootstrap/bin/rustc.rs
+++ b/src/bootstrap/bin/rustc.rs
@@ -114,10 +114,6 @@ fn main() {
 
     cmd.env("RUSTC_BREAK_ON_ICE", "1");
 
-    if args.iter().find(|s| **s == OsString::from("___")).is_some() {
-        cmd.arg("-Zcodegen-backend=metadata_only");
-    }
-
     if let Some(target) = target {
         // The stage0 compiler has a special sysroot distinct from what we
         // actually downloaded, so we just always pass the `--sysroot` option.
diff --git a/src/bootstrap/builder.rs b/src/bootstrap/builder.rs
index fad0a553802a..d2f9b2653d50 100644
--- a/src/bootstrap/builder.rs
+++ b/src/bootstrap/builder.rs
@@ -893,7 +893,7 @@ impl<'a> Builder<'a> {
         //
         // If LLVM support is disabled we need to use the snapshot compiler to compile
         // build scripts, as the new compiler doesn't support executables.
-        if mode == Mode::Std || !self.config.llvm_enabled {
+        if mode == Mode::Std || self.config.rust_codegen_backends.is_empty() {
             cargo
                 .env("RUSTC_SNAPSHOT", &self.initial_rustc)
                 .env("RUSTC_SNAPSHOT_LIBDIR", self.rustc_snapshot_libdir());
diff --git a/src/bootstrap/config.rs b/src/bootstrap/config.rs
index b3ed10257bda..2e629456b7ef 100644
--- a/src/bootstrap/config.rs
+++ b/src/bootstrap/config.rs
@@ -74,7 +74,6 @@ pub struct Config {
     pub backtrace_on_ice: bool,
 
     // llvm codegen options
-    pub llvm_enabled: bool,
     pub llvm_assertions: bool,
     pub llvm_optimize: bool,
     pub llvm_release_debuginfo: bool,
@@ -239,7 +238,6 @@ struct Install {
 #[derive(Deserialize, Default)]
 #[serde(deny_unknown_fields, rename_all = "kebab-case")]
 struct Llvm {
-    enabled: Option<bool>,
     ccache: Option<StringOrBool>,
     ninja: Option<bool>,
     assertions: Option<bool>,
@@ -341,7 +339,6 @@ impl Config {
 
     pub fn default_opts() -> Config {
         let mut config = Config::default();
-        config.llvm_enabled = true;
         config.llvm_optimize = true;
         config.llvm_version_check = true;
         config.use_jemalloc = true;
@@ -496,7 +493,6 @@ impl Config {
                 Some(StringOrBool::Bool(false)) | None => {}
             }
             set(&mut config.ninja, llvm.ninja);
-            set(&mut config.llvm_enabled, llvm.enabled);
             llvm_assertions = llvm.assertions;
             set(&mut config.llvm_optimize, llvm.optimize);
             set(&mut config.llvm_release_debuginfo, llvm.release_debuginfo);
diff --git a/src/bootstrap/test.rs b/src/bootstrap/test.rs
index 6254f9816566..917b85690dea 100644
--- a/src/bootstrap/test.rs
+++ b/src/bootstrap/test.rs
@@ -1096,7 +1096,7 @@ impl Step for Compiletest {
             cmd.arg("--quiet");
         }
 
-        if builder.config.llvm_enabled {
+        if !builder.config.rust_codegen_backends.is_empty() {
             let llvm_config = builder.ensure(native::Llvm {
                 target: builder.config.build,
                 emscripten: false,
@@ -1129,7 +1129,7 @@ impl Step for Compiletest {
                 }
             }
         }
-        if suite == "run-make-fulldeps" && !builder.config.llvm_enabled {
+        if suite == "run-make-fulldeps" && builder.config.rust_codegen_backends.is_empty() {
             builder.info(&format!(
                 "Ignoring run-make test suite as they generally don't work without LLVM"
             ));
diff --git a/src/bootstrap/tool.rs b/src/bootstrap/tool.rs
index b3d7b9a91ecf..640dd9ecdd99 100644
--- a/src/bootstrap/tool.rs
+++ b/src/bootstrap/tool.rs
@@ -672,7 +672,7 @@ impl<'a> Builder<'a> {
     }
 
     fn llvm_bin_path(&self) -> Option<PathBuf> {
-        if self.config.llvm_enabled && !self.config.dry_run {
+        if !self.config.rust_codegen_backends.is_empty() && !self.config.dry_run {
             let llvm_config = self.ensure(native::Llvm {
                 target: self.config.build,
                 emscripten: false,
diff --git a/src/librustc_codegen_utils/Cargo.toml b/src/librustc_codegen_utils/Cargo.toml
index 690fb260390e..77a29ac89f5c 100644
--- a/src/librustc_codegen_utils/Cargo.toml
+++ b/src/librustc_codegen_utils/Cargo.toml
@@ -10,8 +10,6 @@ crate-type = ["dylib"]
 test = false
 
 [dependencies]
-ar = "0.3.0"
-flate2 = "1.0"
 log = "0.4"
 
 syntax = { path = "../libsyntax" }
diff --git a/src/librustc_codegen_utils/codegen_backend.rs b/src/librustc_codegen_utils/codegen_backend.rs
index 8b52d61fd9e5..25d01ace4cae 100644
--- a/src/librustc_codegen_utils/codegen_backend.rs
+++ b/src/librustc_codegen_utils/codegen_backend.rs
@@ -22,17 +22,13 @@
 #![feature(box_syntax)]
 
 use std::any::Any;
-use std::io::prelude::*;
-use std::io::{self, Cursor};
+use std::io::{self, Write};
 use std::fs::File;
 use std::path::Path;
 use std::sync::{mpsc, Arc};
 
 use rustc_data_structures::owning_ref::OwningRef;
 use rustc_data_structures::sync::Lrc;
-use ar::{Archive, Builder, Header};
-use flate2::Compression;
-use flate2::write::DeflateEncoder;
 
 use syntax::symbol::Symbol;
 use rustc::hir::def_id::LOCAL_CRATE;
@@ -80,96 +76,27 @@ pub trait CodegenBackend {
     ) -> Result<(), CompileIncomplete>;
 }
 
-pub struct DummyCodegenBackend;
-
-impl CodegenBackend for DummyCodegenBackend {
-    fn metadata_loader(&self) -> Box<MetadataLoader + Sync> {
-        box DummyMetadataLoader(())
-    }
-
-    fn provide(&self, _providers: &mut Providers) {
-        bug!("DummyCodegenBackend::provide");
-    }
-
-    fn provide_extern(&self, _providers: &mut Providers) {
-        bug!("DummyCodegenBackend::provide_extern");
-    }
-
-    fn codegen_crate<'a, 'tcx>(
-        &self,
-        _tcx: TyCtxt<'a, 'tcx, 'tcx>,
-        _rx: mpsc::Receiver<Box<Any + Send>>
-    ) -> Box<Any> {
-        bug!("DummyCodegenBackend::codegen_backend");
-    }
-
-    fn join_codegen_and_link(
-        &self,
-        _ongoing_codegen: Box<Any>,
-        _sess: &Session,
-        _dep_graph: &DepGraph,
-        _outputs: &OutputFilenames,
-    ) -> Result<(), CompileIncomplete> {
-        bug!("DummyCodegenBackend::join_codegen_and_link");
-    }
-}
-
-pub struct DummyMetadataLoader(());
-
-impl MetadataLoader for DummyMetadataLoader {
-    fn get_rlib_metadata(
-        &self,
-        _target: &Target,
-        _filename: &Path
-    ) -> Result<MetadataRef, String> {
-        bug!("DummyMetadataLoader::get_rlib_metadata");
-    }
-
-    fn get_dylib_metadata(
-        &self,
-        _target: &Target,
-        _filename: &Path
-    ) -> Result<MetadataRef, String> {
-        bug!("DummyMetadataLoader::get_dylib_metadata");
-    }
-}
-
 pub struct NoLlvmMetadataLoader;
 
 impl MetadataLoader for NoLlvmMetadataLoader {
     fn get_rlib_metadata(&self, _: &Target, filename: &Path) -> Result<MetadataRef, String> {
-        let file = File::open(filename)
+        let mut file = File::open(filename)
             .map_err(|e| format!("metadata file open err: {:?}", e))?;
-        let mut archive = Archive::new(file);
 
-        while let Some(entry_result) = archive.next_entry() {
-            let mut entry = entry_result
-                .map_err(|e| format!("metadata section read err: {:?}", e))?;
-            if entry.header().identifier() == "rust.metadata.bin" {
-                let mut buf = Vec::new();
-                io::copy(&mut entry, &mut buf).unwrap();
-                let buf: OwningRef<Vec<u8>, [u8]> = OwningRef::new(buf).into();
-                return Ok(rustc_erase_owner!(buf.map_owner_box()));
-            }
-        }
-
-        Err("Couldn't find metadata section".to_string())
+        let mut buf = Vec::new();
+        io::copy(&mut file, &mut buf).unwrap();
+        let buf: OwningRef<Vec<u8>, [u8]> = OwningRef::new(buf).into();
+        return Ok(rustc_erase_owner!(buf.map_owner_box()));
     }
 
-    fn get_dylib_metadata(
-        &self,
-        _target: &Target,
-        _filename: &Path,
-    ) -> Result<MetadataRef, String> {
-        // FIXME: Support reading dylibs from llvm enabled rustc
-        self.get_rlib_metadata(_target, _filename)
+    fn get_dylib_metadata(&self, target: &Target, filename: &Path) -> Result<MetadataRef, String> {
+        self.get_rlib_metadata(target, filename)
     }
 }
 
 pub struct MetadataOnlyCodegenBackend(());
 pub struct OngoingCodegen {
     metadata: EncodedMetadata,
-    metadata_version: Vec<u8>,
     crate_name: Symbol,
 }
 
@@ -257,7 +184,6 @@ impl CodegenBackend for MetadataOnlyCodegenBackend {
 
         box OngoingCodegen {
             metadata: metadata,
-            metadata_version: tcx.metadata_encoding_version().to_vec(),
             crate_name: tcx.crate_name(LOCAL_CRATE),
         }
     }
@@ -277,18 +203,9 @@ impl CodegenBackend for MetadataOnlyCodegenBackend {
             }
             let output_name =
                 out_filename(sess, crate_type, &outputs, &ongoing_codegen.crate_name.as_str());
-            let mut compressed = ongoing_codegen.metadata_version.clone();
-            let metadata = if crate_type == CrateType::CrateTypeDylib {
-                DeflateEncoder::new(&mut compressed, Compression::fast())
-                    .write_all(&ongoing_codegen.metadata.raw_data)
-                    .unwrap();
-                &compressed
-            } else {
-                &ongoing_codegen.metadata.raw_data
-            };
-            let mut builder = Builder::new(File::create(&output_name).unwrap());
-            let header = Header::new("rust.metadata.bin".to_string(), metadata.len() as u64);
-            builder.append(&header, Cursor::new(metadata)).unwrap();
+            let metadata = &ongoing_codegen.metadata.raw_data;
+            let mut file = File::create(&output_name).unwrap();
+            file.write_all(metadata).unwrap();
         }
 
         sess.abort_if_errors();
diff --git a/src/librustc_codegen_utils/lib.rs b/src/librustc_codegen_utils/lib.rs
index 058e4b7841f5..c168f26cd170 100644
--- a/src/librustc_codegen_utils/lib.rs
+++ b/src/librustc_codegen_utils/lib.rs
@@ -25,8 +25,6 @@
 
 #![recursion_limit="256"]
 
-extern crate ar;
-extern crate flate2;
 #[macro_use]
 extern crate log;
 
@@ -39,8 +37,6 @@ extern crate syntax;
 extern crate syntax_pos;
 #[macro_use] extern crate rustc_data_structures;
 
-pub extern crate rustc as __rustc;
-
 use rustc::ty::TyCtxt;
 
 pub mod link;
diff --git a/src/tools/tidy/src/deps.rs b/src/tools/tidy/src/deps.rs
index dedf42fecbbd..942d27202ecd 100644
--- a/src/tools/tidy/src/deps.rs
+++ b/src/tools/tidy/src/deps.rs
@@ -59,7 +59,6 @@ static WHITELIST_CRATES: &'static [CrateVersion] = &[
 /// Whitelist of crates rustc is allowed to depend on. Avoid adding to the list if possible.
 static WHITELIST: &'static [Crate] = &[
     Crate("aho-corasick"),
-    Crate("ar"),
     Crate("arrayvec"),
     Crate("atty"),
     Crate("backtrace"),

From edd6ed571f9886d4b01fe87812442d5e81d1c895 Mon Sep 17 00:00:00 2001
From: bjorn3 <bjorn3@users.noreply.github.com>
Date: Sat, 16 Jun 2018 12:07:54 +0200
Subject: [PATCH 03/19] Fix some errors

---
 src/librustc_codegen_llvm/glue.rs             | 122 ------------------
 src/librustc_codegen_llvm/intrinsic.rs        |   5 +-
 src/librustc_codegen_llvm/lib.rs              |   1 -
 src/librustc_codegen_llvm/mir/place.rs        |   7 +-
 src/librustc_codegen_llvm/mono_item.rs        |   1 -
 src/librustc_codegen_llvm/type_of.rs          |   2 +-
 .../llvm_target_features.rs                   |  10 ++
 7 files changed, 17 insertions(+), 131 deletions(-)
 delete mode 100644 src/librustc_codegen_llvm/glue.rs

diff --git a/src/librustc_codegen_llvm/glue.rs b/src/librustc_codegen_llvm/glue.rs
deleted file mode 100644
index c7275d094018..000000000000
--- a/src/librustc_codegen_llvm/glue.rs
+++ /dev/null
@@ -1,122 +0,0 @@
-// Copyright 2012-2013 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.
-
-//!
-//
-// Code relating to drop glue.
-
-use std;
-
-use builder::Builder;
-use common::*;
-use llvm::{ValueRef};
-use llvm;
-use meth;
-use rustc::ty::layout::LayoutOf;
-use rustc::ty::{self, Ty};
-use value::Value;
-
-pub fn size_and_align_of_dst<'a, 'tcx>(bx: &Builder<'a, 'tcx>, t: Ty<'tcx>, info: ValueRef)
-                                       -> (ValueRef, ValueRef) {
-    debug!("calculate size of DST: {}; with lost info: {:?}",
-           t, Value(info));
-    if bx.cx.type_is_sized(t) {
-        let (size, align) = bx.cx.size_and_align_of(t);
-        debug!("size_and_align_of_dst t={} info={:?} size: {:?} align: {:?}",
-               t, Value(info), size, align);
-        let size = C_usize(bx.cx, size.bytes());
-        let align = C_usize(bx.cx, align.abi());
-        return (size, align);
-    }
-    assert!(!info.is_null());
-    match t.sty {
-        ty::TyDynamic(..) => {
-            // load size/align from vtable
-            (meth::SIZE.get_usize(bx, info), meth::ALIGN.get_usize(bx, info))
-        }
-        ty::TySlice(_) | ty::TyStr => {
-            let unit = t.sequence_element_type(bx.tcx());
-            // The info in this case is the length of the str, so the size is that
-            // times the unit size.
-            let (size, align) = bx.cx.size_and_align_of(unit);
-            (bx.mul(info, C_usize(bx.cx, size.bytes())),
-             C_usize(bx.cx, align.abi()))
-        }
-        _ => {
-            let cx = bx.cx;
-            // First get the size of all statically known fields.
-            // Don't use size_of because it also rounds up to alignment, which we
-            // want to avoid, as the unsized field's alignment could be smaller.
-            assert!(!t.is_simd());
-            let layout = cx.layout_of(t);
-            debug!("DST {} layout: {:?}", t, layout);
-
-            let i = layout.fields.count() - 1;
-            let sized_size = layout.fields.offset(i).bytes();
-            let sized_align = layout.align.abi();
-            debug!("DST {} statically sized prefix size: {} align: {}",
-                   t, sized_size, sized_align);
-            let sized_size = C_usize(cx, sized_size);
-            let sized_align = C_usize(cx, sized_align);
-
-            // Recurse to get the size of the dynamically sized field (must be
-            // the last field).
-            let field_ty = layout.field(cx, i).ty;
-            let (unsized_size, mut unsized_align) = size_and_align_of_dst(bx, field_ty, info);
-
-            // FIXME (#26403, #27023): We should be adding padding
-            // to `sized_size` (to accommodate the `unsized_align`
-            // required of the unsized field that follows) before
-            // summing it with `sized_size`. (Note that since #26403
-            // is unfixed, we do not yet add the necessary padding
-            // here. But this is where the add would go.)
-
-            // Return the sum of sizes and max of aligns.
-            let size = bx.add(sized_size, unsized_size);
-
-            // Packed types ignore the alignment of their fields.
-            if let ty::TyAdt(def, _) = t.sty {
-                if def.repr.packed() {
-                    unsized_align = sized_align;
-                }
-            }
-
-            // Choose max of two known alignments (combined value must
-            // be aligned according to more restrictive of the two).
-            let align = match (const_to_opt_u128(sized_align, false),
-                               const_to_opt_u128(unsized_align, false)) {
-                (Some(sized_align), Some(unsized_align)) => {
-                    // If both alignments are constant, (the sized_align should always be), then
-                    // pick the correct alignment statically.
-                    C_usize(cx, std::cmp::max(sized_align, unsized_align) as u64)
-                }
-                _ => bx.select(bx.icmp(llvm::IntUGT, sized_align, unsized_align),
-                                sized_align,
-                                unsized_align)
-            };
-
-            // Issue #27023: must add any necessary padding to `size`
-            // (to make it a multiple of `align`) before returning it.
-            //
-            // Namely, the returned size should be, in C notation:
-            //
-            //   `size + ((size & (align-1)) ? align : 0)`
-            //
-            // emulated via the semi-standard fast bit trick:
-            //
-            //   `(size + (align-1)) & -align`
-
-            let addend = bx.sub(align, C_usize(bx.cx, 1));
-            let size = bx.and(bx.add(size, addend), bx.neg(align));
-
-            (size, align)
-        }
-    }
-}
diff --git a/src/librustc_codegen_llvm/intrinsic.rs b/src/librustc_codegen_llvm/intrinsic.rs
index 6bb5456f9034..d7a068265a9e 100644
--- a/src/librustc_codegen_llvm/intrinsic.rs
+++ b/src/librustc_codegen_llvm/intrinsic.rs
@@ -19,7 +19,6 @@ use mir::operand::{OperandRef, OperandValue};
 use base::*;
 use common::*;
 use declare;
-use glue;
 use type_::Type;
 use type_of::LayoutLlvmExt;
 use rustc::ty::{self, Ty};
@@ -146,7 +145,7 @@ pub fn codegen_intrinsic_call<'a, 'tcx>(bx: &Builder<'a, 'tcx>,
             let tp_ty = substs.type_at(0);
             if let OperandValue::Pair(_, meta) = args[0].val {
                 let (llsize, _) =
-                    glue::size_and_align_of_dst(bx, tp_ty, meta);
+                    size_and_align_of_dst(bx, tp_ty, meta);
                 llsize
             } else {
                 C_usize(cx, cx.size_of(tp_ty).bytes())
@@ -160,7 +159,7 @@ pub fn codegen_intrinsic_call<'a, 'tcx>(bx: &Builder<'a, 'tcx>,
             let tp_ty = substs.type_at(0);
             if let OperandValue::Pair(_, meta) = args[0].val {
                 let (_, llalign) =
-                    glue::size_and_align_of_dst(bx, tp_ty, meta);
+                    size_and_align_of_dst(bx, tp_ty, meta);
                 llalign
             } else {
                 C_usize(cx, cx.align_of(tp_ty).abi())
diff --git a/src/librustc_codegen_llvm/lib.rs b/src/librustc_codegen_llvm/lib.rs
index eee4e5f8f7a0..fd2d1f538876 100644
--- a/src/librustc_codegen_llvm/lib.rs
+++ b/src/librustc_codegen_llvm/lib.rs
@@ -109,7 +109,6 @@ mod consts;
 mod context;
 mod debuginfo;
 mod declare;
-mod glue;
 mod intrinsic;
 mod llvm_util;
 mod metadata;
diff --git a/src/librustc_codegen_llvm/mir/place.rs b/src/librustc_codegen_llvm/mir/place.rs
index 2a1e3980adbc..93c31286932e 100644
--- a/src/librustc_codegen_llvm/mir/place.rs
+++ b/src/librustc_codegen_llvm/mir/place.rs
@@ -16,12 +16,13 @@ use rustc::mir::tcx::PlaceTy;
 use rustc_data_structures::indexed_vec::Idx;
 use base;
 use builder::Builder;
-use common::{CodegenCx, C_undef, C_usize, C_u8, C_u32, C_uint, C_null, C_uint_big};
+use common::{
+    CodegenCx, C_undef, C_usize, C_u8, C_u32, C_uint, C_null, C_uint_big,size_and_align_of_dst
+};
 use consts;
 use type_of::LayoutLlvmExt;
 use type_::Type;
 use value::Value;
-use glue;
 
 use std::ptr;
 
@@ -222,7 +223,7 @@ impl<'a, 'tcx> PlaceRef<'tcx> {
         let unaligned_offset = C_usize(cx, offset.bytes());
 
         // Get the alignment of the field
-        let (_, unsized_align) = glue::size_and_align_of_dst(bx, field.ty, meta);
+        let (_, unsized_align) = size_and_align_of_dst(bx, field.ty, meta);
 
         // Bump the unaligned offset up to the appropriate alignment using the
         // following expression:
diff --git a/src/librustc_codegen_llvm/mono_item.rs b/src/librustc_codegen_llvm/mono_item.rs
index 61f4bc3e6bc8..2f7b27b85afe 100644
--- a/src/librustc_codegen_llvm/mono_item.rs
+++ b/src/librustc_codegen_llvm/mono_item.rs
@@ -33,7 +33,6 @@ use std::fmt;
 
 pub use rustc::mir::mono::MonoItem;
 
-use rustc_mir::monomorphize::item::*;
 pub use rustc_mir::monomorphize::item::MonoItemExt as BaseMonoItemExt;
 
 pub trait MonoItemExt<'a, 'tcx>: fmt::Debug + BaseMonoItemExt<'a, 'tcx> {
diff --git a/src/librustc_codegen_llvm/type_of.rs b/src/librustc_codegen_llvm/type_of.rs
index 88b75ff9c094..bfabf65dfd85 100644
--- a/src/librustc_codegen_llvm/type_of.rs
+++ b/src/librustc_codegen_llvm/type_of.rs
@@ -16,7 +16,7 @@ use rustc::ty::{self, Ty, TypeFoldable};
 use rustc::ty::layout::{self, Align, LayoutOf, Size, TyLayout};
 use rustc_target::spec::PanicStrategy;
 use rustc_target::abi::FloatTy;
-use mono_item::DefPathBasedNames;
+use rustc_mir::monomorphize::item::DefPathBasedNames;
 use type_::Type;
 
 use std::fmt::Write;
diff --git a/src/librustc_codegen_utils/llvm_target_features.rs b/src/librustc_codegen_utils/llvm_target_features.rs
index 82cd397be232..8e11363cead8 100644
--- a/src/librustc_codegen_utils/llvm_target_features.rs
+++ b/src/librustc_codegen_utils/llvm_target_features.rs
@@ -1,3 +1,13 @@
+// Copyright 2017 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 rustc::session::Session;
 
 // WARNING: the features after applying `to_llvm_feature` must be known

From f44ec6439b31caa92ee394f65aae7d4a1a5341dd Mon Sep 17 00:00:00 2001
From: bjorn3 <bjorn3@users.noreply.github.com>
Date: Sat, 16 Jun 2018 16:46:03 +0200
Subject: [PATCH 04/19] Undo unnecessary change

---
 src/librustc_codegen_llvm/base.rs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/librustc_codegen_llvm/base.rs b/src/librustc_codegen_llvm/base.rs
index 53c70eb42ce5..f9d843194337 100644
--- a/src/librustc_codegen_llvm/base.rs
+++ b/src/librustc_codegen_llvm/base.rs
@@ -93,6 +93,8 @@ use syntax::ast;
 
 use mir::operand::OperandValue;
 
+use rustc_codegen_utils::check_for_rustc_errors_attr;
+
 pub struct StatRecorder<'a, 'tcx: 'a> {
     cx: &'a CodegenCx<'a, 'tcx>,
     name: Option<String>,
@@ -714,7 +716,7 @@ pub fn codegen_crate<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                              rx: mpsc::Receiver<Box<Any + Send>>)
                              -> OngoingCodegen {
 
-    ::rustc_codegen_utils::check_for_rustc_errors_attr(tcx);
+    check_for_rustc_errors_attr(tcx);
 
     if let Some(true) = tcx.sess.opts.debugging_opts.thinlto {
         if unsafe { !llvm::LLVMRustThinLTOAvailable() } {

From d7bc2937464b760d69ae8fc1146b660dc867e802 Mon Sep 17 00:00:00 2001
From: bjorn3 <bjorn3@users.noreply.github.com>
Date: Sat, 16 Jun 2018 18:46:54 +0200
Subject: [PATCH 05/19] Solve review comment

---
 src/bootstrap/compile.rs | 19 ++++++++-----------
 1 file changed, 8 insertions(+), 11 deletions(-)

diff --git a/src/bootstrap/compile.rs b/src/bootstrap/compile.rs
index e23566d52f0b..524df9587dad 100644
--- a/src/bootstrap/compile.rs
+++ b/src/bootstrap/compile.rs
@@ -645,14 +645,13 @@ impl Step for CodegenBackend {
 
     fn make_run(run: RunConfig) {
         let backend = run.builder.config.rust_codegen_backends.get(0);
-        let backend = backend.cloned().unwrap_or_else(|| {
-            INTERNER.intern_str("llvm")
-        });
-        run.builder.ensure(CodegenBackend {
-            compiler: run.builder.compiler(run.builder.top_stage, run.host),
-            target: run.target,
-            backend,
-        });
+        if let Some(backend) = backend.cloned() {
+            run.builder.ensure(CodegenBackend {
+                compiler: run.builder.compiler(run.builder.top_stage, run.host),
+                target: run.target,
+                backend,
+            });
+        }
     }
 
     fn run(self, builder: &Builder) {
@@ -677,9 +676,7 @@ impl Step for CodegenBackend {
             .arg(builder.src.join("src/librustc_codegen_llvm/Cargo.toml"));
         rustc_cargo_env(builder, &mut cargo);
 
-        if !backend.is_empty() {
-            features += &build_codegen_backend(&builder, &mut cargo, &compiler, target, backend);
-        }
+        features += &build_codegen_backend(&builder, &mut cargo, &compiler, target, backend);
 
         let tmp_stamp = builder.cargo_out(compiler, Mode::Codegen, target)
             .join(".tmp.stamp");

From 097de536e43e0040e5966ee8e4c75e84c973b2e0 Mon Sep 17 00:00:00 2001
From: bjorn3 <bjorn3@users.noreply.github.com>
Date: Mon, 18 Jun 2018 18:13:00 +0200
Subject: [PATCH 06/19] Fix metadata_only metadata encoding

---
 src/librustc_codegen_utils/Cargo.toml         |  1 +
 src/librustc_codegen_utils/codegen_backend.rs | 14 +++++++++++++-
 src/librustc_codegen_utils/lib.rs             |  1 +
 3 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/src/librustc_codegen_utils/Cargo.toml b/src/librustc_codegen_utils/Cargo.toml
index 77a29ac89f5c..30f533285ddf 100644
--- a/src/librustc_codegen_utils/Cargo.toml
+++ b/src/librustc_codegen_utils/Cargo.toml
@@ -10,6 +10,7 @@ crate-type = ["dylib"]
 test = false
 
 [dependencies]
+flate2 = "1.0"
 log = "0.4"
 
 syntax = { path = "../libsyntax" }
diff --git a/src/librustc_codegen_utils/codegen_backend.rs b/src/librustc_codegen_utils/codegen_backend.rs
index 25d01ace4cae..c8cb92b7782f 100644
--- a/src/librustc_codegen_utils/codegen_backend.rs
+++ b/src/librustc_codegen_utils/codegen_backend.rs
@@ -29,6 +29,8 @@ use std::sync::{mpsc, Arc};
 
 use rustc_data_structures::owning_ref::OwningRef;
 use rustc_data_structures::sync::Lrc;
+use flate2::Compression;
+use flate2::write::DeflateEncoder;
 
 use syntax::symbol::Symbol;
 use rustc::hir::def_id::LOCAL_CRATE;
@@ -97,6 +99,7 @@ impl MetadataLoader for NoLlvmMetadataLoader {
 pub struct MetadataOnlyCodegenBackend(());
 pub struct OngoingCodegen {
     metadata: EncodedMetadata,
+    metadata_version: Vec<u8>,
     crate_name: Symbol,
 }
 
@@ -184,6 +187,7 @@ impl CodegenBackend for MetadataOnlyCodegenBackend {
 
         box OngoingCodegen {
             metadata: metadata,
+            metadata_version: tcx.metadata_encoding_version().to_vec(),
             crate_name: tcx.crate_name(LOCAL_CRATE),
         }
     }
@@ -203,7 +207,15 @@ impl CodegenBackend for MetadataOnlyCodegenBackend {
             }
             let output_name =
                 out_filename(sess, crate_type, &outputs, &ongoing_codegen.crate_name.as_str());
-            let metadata = &ongoing_codegen.metadata.raw_data;
+            let mut compressed = ongoing_codegen.metadata_version.clone();
+            let metadata = if crate_type == CrateType::CrateTypeDylib {
+                DeflateEncoder::new(&mut compressed, Compression::fast())
+                    .write_all(&ongoing_codegen.metadata.raw_data)
+                    .unwrap();
+                &compressed
+            } else {
+                &ongoing_codegen.metadata.raw_data
+            };
             let mut file = File::create(&output_name).unwrap();
             file.write_all(metadata).unwrap();
         }
diff --git a/src/librustc_codegen_utils/lib.rs b/src/librustc_codegen_utils/lib.rs
index c168f26cd170..0298162bbb51 100644
--- a/src/librustc_codegen_utils/lib.rs
+++ b/src/librustc_codegen_utils/lib.rs
@@ -25,6 +25,7 @@
 
 #![recursion_limit="256"]
 
+extern crate flate2;
 #[macro_use]
 extern crate log;
 

From e65db8161d39e1f27a1c525027c92f8f0aa7f97c Mon Sep 17 00:00:00 2001
From: bjorn3 <bjorn3@users.noreply.github.com>
Date: Tue, 19 Jun 2018 10:52:13 +0200
Subject: [PATCH 07/19] Fix test

---
 src/test/run-make-fulldeps/hotplug_codegen_backend/Makefile  | 2 +-
 .../run-make-fulldeps/hotplug_codegen_backend/some_crate.rs  | 5 ++---
 .../run-make-fulldeps/hotplug_codegen_backend/the_backend.rs | 2 +-
 3 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/src/test/run-make-fulldeps/hotplug_codegen_backend/Makefile b/src/test/run-make-fulldeps/hotplug_codegen_backend/Makefile
index 2ddf3aa5439f..e203ec2737fc 100644
--- a/src/test/run-make-fulldeps/hotplug_codegen_backend/Makefile
+++ b/src/test/run-make-fulldeps/hotplug_codegen_backend/Makefile
@@ -4,6 +4,6 @@ all:
 	/bin/echo || exit 0 # This test requires /bin/echo to exist
 	$(RUSTC) the_backend.rs --crate-name the_backend --crate-type dylib \
 		-o $(TMPDIR)/the_backend.dylib
-	$(RUSTC) some_crate.rs --crate-name some_crate --crate-type bin -o $(TMPDIR)/some_crate \
+	$(RUSTC) some_crate.rs --crate-name some_crate --crate-type lib -o $(TMPDIR)/some_crate \
 		-Z codegen-backend=$(TMPDIR)/the_backend.dylib -Z unstable-options
 	grep -x "This has been \"compiled\" successfully." $(TMPDIR)/some_crate
diff --git a/src/test/run-make-fulldeps/hotplug_codegen_backend/some_crate.rs b/src/test/run-make-fulldeps/hotplug_codegen_backend/some_crate.rs
index 26ffce01b2e2..bfa8b6b3ef69 100644
--- a/src/test/run-make-fulldeps/hotplug_codegen_backend/some_crate.rs
+++ b/src/test/run-make-fulldeps/hotplug_codegen_backend/some_crate.rs
@@ -8,6 +8,5 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-fn main() {
-    ::std::process::exit(1);
-}
+#![feature(no_core)]
+#![no_core]
diff --git a/src/test/run-make-fulldeps/hotplug_codegen_backend/the_backend.rs b/src/test/run-make-fulldeps/hotplug_codegen_backend/the_backend.rs
index 439bc017fee6..a3cd033f8638 100644
--- a/src/test/run-make-fulldeps/hotplug_codegen_backend/the_backend.rs
+++ b/src/test/run-make-fulldeps/hotplug_codegen_backend/the_backend.rs
@@ -63,7 +63,7 @@ impl CodegenBackend for TheBackend {
         let crate_name = ongoing_codegen.downcast::<Symbol>()
             .expect("in join_codegen_and_link: ongoing_codegen is not a Symbol");
         for &crate_type in sess.opts.crate_types.iter() {
-            if crate_type != CrateType::CrateTypeExecutable {
+            if crate_type != CrateType::CrateTypeRlib {
                 sess.fatal(&format!("Crate type is {:?}", crate_type));
             }
             let output_name =

From cd4989ee94b86914469d917ba848a2cb3a51a72e Mon Sep 17 00:00:00 2001
From: bjorn3 <bjorn3@users.noreply.github.com>
Date: Wed, 20 Jun 2018 09:35:01 +0200
Subject: [PATCH 08/19] Leave fixme comment

---
 src/librustc_codegen_utils/codegen_backend.rs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/librustc_codegen_utils/codegen_backend.rs b/src/librustc_codegen_utils/codegen_backend.rs
index c8cb92b7782f..8043559b3109 100644
--- a/src/librustc_codegen_utils/codegen_backend.rs
+++ b/src/librustc_codegen_utils/codegen_backend.rs
@@ -161,7 +161,8 @@ impl CodegenBackend for MetadataOnlyCodegenBackend {
                 collector::MonoItemCollectionMode::Eager
             ).0.iter()
         );
-        //::rustc::middle::dependency_format::calculate(tcx);
+        // FIXME: Fix this
+        // ::rustc::middle::dependency_format::calculate(tcx);
         let _ = tcx.link_args(LOCAL_CRATE);
         let _ = tcx.native_libraries(LOCAL_CRATE);
         for mono_item in

From b95ef9577632520d44ac10270632de729ac4bc1c Mon Sep 17 00:00:00 2001
From: bjorn3 <bjorn3@users.noreply.github.com>
Date: Thu, 21 Jun 2018 13:12:56 +0200
Subject: [PATCH 09/19] Add comment about disabling LLVM by setting
 codegen-backends empty

---
 config.toml.example | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/config.toml.example b/config.toml.example
index 7bf52a369e37..568790ab4dd6 100644
--- a/config.toml.example
+++ b/config.toml.example
@@ -330,8 +330,8 @@
 # This is an array of the codegen backends that will be compiled for the rustc
 # that's being compiled. The default is to only build the LLVM codegen backend,
 # but you can also optionally enable the "emscripten" backend for asm.js or
-# make this an empty array (but that probably won't get too far in the
-# bootstrap)
+# make this an empty array (that will disable LLVM, but bootstrap will fail at
+# the time the final rustc binary is built for stage 1)
 #codegen-backends = ["llvm"]
 
 # This is the name of the directory in which codegen backends will get installed

From b723bc1fa92647f1d91eabf5b86df22eacd16838 Mon Sep 17 00:00:00 2001
From: bjorn3 <bjorn3@users.noreply.github.com>
Date: Fri, 22 Jun 2018 14:32:49 +0200
Subject: [PATCH 10/19] Change comment on setting codegen-backend empty

---
 config.toml.example | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/config.toml.example b/config.toml.example
index 568790ab4dd6..e120b9b62b48 100644
--- a/config.toml.example
+++ b/config.toml.example
@@ -330,8 +330,8 @@
 # This is an array of the codegen backends that will be compiled for the rustc
 # that's being compiled. The default is to only build the LLVM codegen backend,
 # but you can also optionally enable the "emscripten" backend for asm.js or
-# make this an empty array (that will disable LLVM, but bootstrap will fail at
-# the time the final rustc binary is built for stage 1)
+# make this an empty array (which will disable LLVM, but that probably won't
+# get too far in the bootstrap
 #codegen-backends = ["llvm"]
 
 # This is the name of the directory in which codegen backends will get installed

From c61531dc55296f7c4b58e52b1d3b53dbaa0713cc Mon Sep 17 00:00:00 2001
From: bjorn3 <bjorn3@users.noreply.github.com>
Date: Fri, 22 Jun 2018 14:35:53 +0200
Subject: [PATCH 11/19] Remove unused rustc_driver dependency on ar

---
 src/librustc_driver/Cargo.toml | 2 --
 1 file changed, 2 deletions(-)

diff --git a/src/librustc_driver/Cargo.toml b/src/librustc_driver/Cargo.toml
index 5b75912c18f5..7a020f331e50 100644
--- a/src/librustc_driver/Cargo.toml
+++ b/src/librustc_driver/Cargo.toml
@@ -37,5 +37,3 @@ serialize = { path = "../libserialize" }
 syntax = { path = "../libsyntax" }
 syntax_ext = { path = "../libsyntax_ext" }
 syntax_pos = { path = "../libsyntax_pos" }
-
-ar = "0.3.0"

From c5a6b51e442287d31b12591225d2e81a4345074d Mon Sep 17 00:00:00 2001
From: bjorn3 <bjorn3@users.noreply.github.com>
Date: Fri, 22 Jun 2018 19:28:06 +0200
Subject: [PATCH 12/19] Update Cargo.lock and move size_and_align_of_dst back

---
 src/librustc_codegen_llvm/common.rs    | 104 +--------------------
 src/librustc_codegen_llvm/glue.rs      | 122 +++++++++++++++++++++++++
 src/librustc_codegen_llvm/intrinsic.rs |   5 +-
 src/librustc_codegen_llvm/lib.rs       |   1 +
 src/librustc_codegen_llvm/mir/place.rs |   7 +-
 5 files changed, 132 insertions(+), 107 deletions(-)
 create mode 100644 src/librustc_codegen_llvm/glue.rs

diff --git a/src/librustc_codegen_llvm/common.rs b/src/librustc_codegen_llvm/common.rs
index 099d717e3c00..7e55642814bb 100644
--- a/src/librustc_codegen_llvm/common.rs
+++ b/src/librustc_codegen_llvm/common.rs
@@ -12,7 +12,9 @@
 
 //! Code that is useful in various codegen modules.
 
-use llvm::{self, ValueRef, ContextRef, TypeKind, True, False, Bool, OperandBundleDef};
+use llvm;
+use llvm::{ValueRef, ContextRef, TypeKind};
+use llvm::{True, False, Bool, OperandBundleDef};
 use rustc::hir::def_id::DefId;
 use rustc::middle::lang_items::LangItem;
 use abi;
@@ -27,8 +29,6 @@ use rustc::ty::{self, Ty, TyCtxt};
 use rustc::ty::layout::{HasDataLayout, LayoutOf};
 use rustc::hir;
 
-use meth;
-
 use libc::{c_uint, c_char};
 use std::iter;
 
@@ -448,101 +448,3 @@ pub fn ty_fn_sig<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
         _ => bug!("unexpected type {:?} to ty_fn_sig", ty)
     }
 }
-
-pub fn size_and_align_of_dst<'a, 'tcx>(bx: &Builder<'a, 'tcx>, t: Ty<'tcx>, info: ValueRef)
-                                       -> (ValueRef, ValueRef) {
-    debug!("calculate size of DST: {}; with lost info: {:?}",
-           t, Value(info));
-    if bx.cx.type_is_sized(t) {
-        let (size, align) = bx.cx.size_and_align_of(t);
-        debug!("size_and_align_of_dst t={} info={:?} size: {:?} align: {:?}",
-               t, Value(info), size, align);
-        let size = C_usize(bx.cx, size.bytes());
-        let align = C_usize(bx.cx, align.abi());
-        return (size, align);
-    }
-    assert!(!info.is_null());
-    match t.sty {
-        ty::TyDynamic(..) => {
-            // load size/align from vtable
-            (meth::SIZE.get_usize(bx, info), meth::ALIGN.get_usize(bx, info))
-        }
-        ty::TySlice(_) | ty::TyStr => {
-            let unit = t.sequence_element_type(bx.tcx());
-            // The info in this case is the length of the str, so the size is that
-            // times the unit size.
-            let (size, align) = bx.cx.size_and_align_of(unit);
-            (bx.mul(info, C_usize(bx.cx, size.bytes())),
-             C_usize(bx.cx, align.abi()))
-        }
-        _ => {
-            let cx = bx.cx;
-            // First get the size of all statically known fields.
-            // Don't use size_of because it also rounds up to alignment, which we
-            // want to avoid, as the unsized field's alignment could be smaller.
-            assert!(!t.is_simd());
-            let layout = cx.layout_of(t);
-            debug!("DST {} layout: {:?}", t, layout);
-
-            let i = layout.fields.count() - 1;
-            let sized_size = layout.fields.offset(i).bytes();
-            let sized_align = layout.align.abi();
-            debug!("DST {} statically sized prefix size: {} align: {}",
-                   t, sized_size, sized_align);
-            let sized_size = C_usize(cx, sized_size);
-            let sized_align = C_usize(cx, sized_align);
-
-            // Recurse to get the size of the dynamically sized field (must be
-            // the last field).
-            let field_ty = layout.field(cx, i).ty;
-            let (unsized_size, mut unsized_align) = size_and_align_of_dst(bx, field_ty, info);
-
-            // FIXME (#26403, #27023): We should be adding padding
-            // to `sized_size` (to accommodate the `unsized_align`
-            // required of the unsized field that follows) before
-            // summing it with `sized_size`. (Note that since #26403
-            // is unfixed, we do not yet add the necessary padding
-            // here. But this is where the add would go.)
-
-            // Return the sum of sizes and max of aligns.
-            let size = bx.add(sized_size, unsized_size);
-
-            // Packed types ignore the alignment of their fields.
-            if let ty::TyAdt(def, _) = t.sty {
-                if def.repr.packed() {
-                    unsized_align = sized_align;
-                }
-            }
-
-            // Choose max of two known alignments (combined value must
-            // be aligned according to more restrictive of the two).
-            let align = match (const_to_opt_u128(sized_align, false),
-                               const_to_opt_u128(unsized_align, false)) {
-                (Some(sized_align), Some(unsized_align)) => {
-                    // If both alignments are constant, (the sized_align should always be), then
-                    // pick the correct alignment statically.
-                    C_usize(cx, ::std::cmp::max(sized_align, unsized_align) as u64)
-                }
-                _ => bx.select(bx.icmp(llvm::IntUGT, sized_align, unsized_align),
-                                sized_align,
-                                unsized_align)
-            };
-
-            // Issue #27023: must add any necessary padding to `size`
-            // (to make it a multiple of `align`) before returning it.
-            //
-            // Namely, the returned size should be, in C notation:
-            //
-            //   `size + ((size & (align-1)) ? align : 0)`
-            //
-            // emulated via the semi-standard fast bit trick:
-            //
-            //   `(size + (align-1)) & -align`
-
-            let addend = bx.sub(align, C_usize(bx.cx, 1));
-            let size = bx.and(bx.add(size, addend), bx.neg(align));
-
-            (size, align)
-        }
-    }
-}
diff --git a/src/librustc_codegen_llvm/glue.rs b/src/librustc_codegen_llvm/glue.rs
new file mode 100644
index 000000000000..c7275d094018
--- /dev/null
+++ b/src/librustc_codegen_llvm/glue.rs
@@ -0,0 +1,122 @@
+// Copyright 2012-2013 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.
+
+//!
+//
+// Code relating to drop glue.
+
+use std;
+
+use builder::Builder;
+use common::*;
+use llvm::{ValueRef};
+use llvm;
+use meth;
+use rustc::ty::layout::LayoutOf;
+use rustc::ty::{self, Ty};
+use value::Value;
+
+pub fn size_and_align_of_dst<'a, 'tcx>(bx: &Builder<'a, 'tcx>, t: Ty<'tcx>, info: ValueRef)
+                                       -> (ValueRef, ValueRef) {
+    debug!("calculate size of DST: {}; with lost info: {:?}",
+           t, Value(info));
+    if bx.cx.type_is_sized(t) {
+        let (size, align) = bx.cx.size_and_align_of(t);
+        debug!("size_and_align_of_dst t={} info={:?} size: {:?} align: {:?}",
+               t, Value(info), size, align);
+        let size = C_usize(bx.cx, size.bytes());
+        let align = C_usize(bx.cx, align.abi());
+        return (size, align);
+    }
+    assert!(!info.is_null());
+    match t.sty {
+        ty::TyDynamic(..) => {
+            // load size/align from vtable
+            (meth::SIZE.get_usize(bx, info), meth::ALIGN.get_usize(bx, info))
+        }
+        ty::TySlice(_) | ty::TyStr => {
+            let unit = t.sequence_element_type(bx.tcx());
+            // The info in this case is the length of the str, so the size is that
+            // times the unit size.
+            let (size, align) = bx.cx.size_and_align_of(unit);
+            (bx.mul(info, C_usize(bx.cx, size.bytes())),
+             C_usize(bx.cx, align.abi()))
+        }
+        _ => {
+            let cx = bx.cx;
+            // First get the size of all statically known fields.
+            // Don't use size_of because it also rounds up to alignment, which we
+            // want to avoid, as the unsized field's alignment could be smaller.
+            assert!(!t.is_simd());
+            let layout = cx.layout_of(t);
+            debug!("DST {} layout: {:?}", t, layout);
+
+            let i = layout.fields.count() - 1;
+            let sized_size = layout.fields.offset(i).bytes();
+            let sized_align = layout.align.abi();
+            debug!("DST {} statically sized prefix size: {} align: {}",
+                   t, sized_size, sized_align);
+            let sized_size = C_usize(cx, sized_size);
+            let sized_align = C_usize(cx, sized_align);
+
+            // Recurse to get the size of the dynamically sized field (must be
+            // the last field).
+            let field_ty = layout.field(cx, i).ty;
+            let (unsized_size, mut unsized_align) = size_and_align_of_dst(bx, field_ty, info);
+
+            // FIXME (#26403, #27023): We should be adding padding
+            // to `sized_size` (to accommodate the `unsized_align`
+            // required of the unsized field that follows) before
+            // summing it with `sized_size`. (Note that since #26403
+            // is unfixed, we do not yet add the necessary padding
+            // here. But this is where the add would go.)
+
+            // Return the sum of sizes and max of aligns.
+            let size = bx.add(sized_size, unsized_size);
+
+            // Packed types ignore the alignment of their fields.
+            if let ty::TyAdt(def, _) = t.sty {
+                if def.repr.packed() {
+                    unsized_align = sized_align;
+                }
+            }
+
+            // Choose max of two known alignments (combined value must
+            // be aligned according to more restrictive of the two).
+            let align = match (const_to_opt_u128(sized_align, false),
+                               const_to_opt_u128(unsized_align, false)) {
+                (Some(sized_align), Some(unsized_align)) => {
+                    // If both alignments are constant, (the sized_align should always be), then
+                    // pick the correct alignment statically.
+                    C_usize(cx, std::cmp::max(sized_align, unsized_align) as u64)
+                }
+                _ => bx.select(bx.icmp(llvm::IntUGT, sized_align, unsized_align),
+                                sized_align,
+                                unsized_align)
+            };
+
+            // Issue #27023: must add any necessary padding to `size`
+            // (to make it a multiple of `align`) before returning it.
+            //
+            // Namely, the returned size should be, in C notation:
+            //
+            //   `size + ((size & (align-1)) ? align : 0)`
+            //
+            // emulated via the semi-standard fast bit trick:
+            //
+            //   `(size + (align-1)) & -align`
+
+            let addend = bx.sub(align, C_usize(bx.cx, 1));
+            let size = bx.and(bx.add(size, addend), bx.neg(align));
+
+            (size, align)
+        }
+    }
+}
diff --git a/src/librustc_codegen_llvm/intrinsic.rs b/src/librustc_codegen_llvm/intrinsic.rs
index d7a068265a9e..6bb5456f9034 100644
--- a/src/librustc_codegen_llvm/intrinsic.rs
+++ b/src/librustc_codegen_llvm/intrinsic.rs
@@ -19,6 +19,7 @@ use mir::operand::{OperandRef, OperandValue};
 use base::*;
 use common::*;
 use declare;
+use glue;
 use type_::Type;
 use type_of::LayoutLlvmExt;
 use rustc::ty::{self, Ty};
@@ -145,7 +146,7 @@ pub fn codegen_intrinsic_call<'a, 'tcx>(bx: &Builder<'a, 'tcx>,
             let tp_ty = substs.type_at(0);
             if let OperandValue::Pair(_, meta) = args[0].val {
                 let (llsize, _) =
-                    size_and_align_of_dst(bx, tp_ty, meta);
+                    glue::size_and_align_of_dst(bx, tp_ty, meta);
                 llsize
             } else {
                 C_usize(cx, cx.size_of(tp_ty).bytes())
@@ -159,7 +160,7 @@ pub fn codegen_intrinsic_call<'a, 'tcx>(bx: &Builder<'a, 'tcx>,
             let tp_ty = substs.type_at(0);
             if let OperandValue::Pair(_, meta) = args[0].val {
                 let (_, llalign) =
-                    size_and_align_of_dst(bx, tp_ty, meta);
+                    glue::size_and_align_of_dst(bx, tp_ty, meta);
                 llalign
             } else {
                 C_usize(cx, cx.align_of(tp_ty).abi())
diff --git a/src/librustc_codegen_llvm/lib.rs b/src/librustc_codegen_llvm/lib.rs
index fd2d1f538876..eee4e5f8f7a0 100644
--- a/src/librustc_codegen_llvm/lib.rs
+++ b/src/librustc_codegen_llvm/lib.rs
@@ -109,6 +109,7 @@ mod consts;
 mod context;
 mod debuginfo;
 mod declare;
+mod glue;
 mod intrinsic;
 mod llvm_util;
 mod metadata;
diff --git a/src/librustc_codegen_llvm/mir/place.rs b/src/librustc_codegen_llvm/mir/place.rs
index 93c31286932e..2a1e3980adbc 100644
--- a/src/librustc_codegen_llvm/mir/place.rs
+++ b/src/librustc_codegen_llvm/mir/place.rs
@@ -16,13 +16,12 @@ use rustc::mir::tcx::PlaceTy;
 use rustc_data_structures::indexed_vec::Idx;
 use base;
 use builder::Builder;
-use common::{
-    CodegenCx, C_undef, C_usize, C_u8, C_u32, C_uint, C_null, C_uint_big,size_and_align_of_dst
-};
+use common::{CodegenCx, C_undef, C_usize, C_u8, C_u32, C_uint, C_null, C_uint_big};
 use consts;
 use type_of::LayoutLlvmExt;
 use type_::Type;
 use value::Value;
+use glue;
 
 use std::ptr;
 
@@ -223,7 +222,7 @@ impl<'a, 'tcx> PlaceRef<'tcx> {
         let unaligned_offset = C_usize(cx, offset.bytes());
 
         // Get the alignment of the field
-        let (_, unsized_align) = size_and_align_of_dst(bx, field.ty, meta);
+        let (_, unsized_align) = glue::size_and_align_of_dst(bx, field.ty, meta);
 
         // Bump the unaligned offset up to the appropriate alignment using the
         // following expression:

From c504d26c1cd4f4dbf9304415b12960c604f01ebf Mon Sep 17 00:00:00 2001
From: bjorn3 <bjorn3@users.noreply.github.com>
Date: Sat, 23 Jun 2018 13:52:52 +0200
Subject: [PATCH 13/19] Move time_graph.rs to rustc/util

---
 src/librustc/lib.rs                                         | 1 +
 src/{librustc_codegen_utils => librustc/util}/time_graph.rs | 0
 src/librustc_codegen_llvm/lib.rs                            | 2 +-
 src/librustc_codegen_utils/lib.rs                           | 1 -
 4 files changed, 2 insertions(+), 2 deletions(-)
 rename src/{librustc_codegen_utils => librustc/util}/time_graph.rs (100%)

diff --git a/src/librustc/lib.rs b/src/librustc/lib.rs
index d8efb582eaa8..8050522d0664 100644
--- a/src/librustc/lib.rs
+++ b/src/librustc/lib.rs
@@ -162,6 +162,7 @@ pub mod util {
     pub mod ppaux;
     pub mod nodemap;
     pub mod fs;
+    pub mod time_graph;
 }
 
 // A private module so that macro-expanded idents like
diff --git a/src/librustc_codegen_utils/time_graph.rs b/src/librustc/util/time_graph.rs
similarity index 100%
rename from src/librustc_codegen_utils/time_graph.rs
rename to src/librustc/util/time_graph.rs
diff --git a/src/librustc_codegen_llvm/lib.rs b/src/librustc_codegen_llvm/lib.rs
index eee4e5f8f7a0..93d9ce1e98a4 100644
--- a/src/librustc_codegen_llvm/lib.rs
+++ b/src/librustc_codegen_llvm/lib.rs
@@ -76,10 +76,10 @@ use rustc::middle::lang_items::LangItem;
 use rustc::session::{Session, CompileIncomplete};
 use rustc::session::config::{OutputFilenames, OutputType, PrintRequest};
 use rustc::ty::{self, TyCtxt};
+use rustc::util::time_graph;
 use rustc::util::nodemap::{FxHashSet, FxHashMap};
 use rustc_mir::monomorphize;
 use rustc_codegen_utils::codegen_backend::CodegenBackend;
-use rustc_codegen_utils::time_graph;
 
 mod diagnostics;
 
diff --git a/src/librustc_codegen_utils/lib.rs b/src/librustc_codegen_utils/lib.rs
index 0298162bbb51..4ac0e3591b3c 100644
--- a/src/librustc_codegen_utils/lib.rs
+++ b/src/librustc_codegen_utils/lib.rs
@@ -44,7 +44,6 @@ pub mod link;
 pub mod codegen_backend;
 pub mod symbol_names;
 pub mod symbol_names_test;
-pub mod time_graph;
 pub mod llvm_target_features;
 
 /// check for the #[rustc_error] annotation, which forces an

From 679743646e7008c2c0c6972cf766914387c4bb52 Mon Sep 17 00:00:00 2001
From: bjorn3 <bjorn3@users.noreply.github.com>
Date: Sat, 23 Jun 2018 17:01:40 +0200
Subject: [PATCH 14/19] Add missing ) to comment

---
 config.toml.example | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/config.toml.example b/config.toml.example
index e120b9b62b48..0de2cce5679d 100644
--- a/config.toml.example
+++ b/config.toml.example
@@ -331,7 +331,7 @@
 # that's being compiled. The default is to only build the LLVM codegen backend,
 # but you can also optionally enable the "emscripten" backend for asm.js or
 # make this an empty array (which will disable LLVM, but that probably won't
-# get too far in the bootstrap
+# get too far in the bootstrap)
 #codegen-backends = ["llvm"]
 
 # This is the name of the directory in which codegen backends will get installed

From c7c534fa0ed1e34c26122de5258b057d15a4ec68 Mon Sep 17 00:00:00 2001
From: bjorn3 <bjorn3@users.noreply.github.com>
Date: Sat, 23 Jun 2018 17:22:35 +0200
Subject: [PATCH 15/19] Move llvm_target_features back to llvm_util

---
 src/librustc_codegen_llvm/llvm_util.rs        | 118 +++++++++++++++-
 src/librustc_codegen_utils/codegen_backend.rs |   5 +-
 src/librustc_codegen_utils/lib.rs             |   1 -
 .../llvm_target_features.rs                   | 127 ------------------
 4 files changed, 118 insertions(+), 133 deletions(-)
 delete mode 100644 src/librustc_codegen_utils/llvm_target_features.rs

diff --git a/src/librustc_codegen_llvm/llvm_util.rs b/src/librustc_codegen_llvm/llvm_util.rs
index b63b43c9c73a..87ee9ef5adb2 100644
--- a/src/librustc_codegen_llvm/llvm_util.rs
+++ b/src/librustc_codegen_llvm/llvm_util.rs
@@ -20,8 +20,6 @@ use syntax::feature_gate::UnstableFeatures;
 use std::sync::atomic::{AtomicBool, Ordering};
 use std::sync::Once;
 
-pub use rustc_codegen_utils::llvm_target_features::*;
-
 static POISONED: AtomicBool = AtomicBool::new(false);
 static INIT: Once = Once::new();
 
@@ -81,6 +79,108 @@ unsafe fn configure_llvm(sess: &Session) {
                                  llvm_args.as_ptr());
 }
 
+// WARNING: the features after applying `to_llvm_feature` must be known
+// to LLVM or the feature detection code will walk past the end of the feature
+// array, leading to crashes.
+
+const ARM_WHITELIST: &[(&str, Option<&str>)] = &[
+    ("mclass", Some("arm_target_feature")),
+    ("neon", Some("arm_target_feature")),
+    ("v7", Some("arm_target_feature")),
+    ("vfp2", Some("arm_target_feature")),
+    ("vfp3", Some("arm_target_feature")),
+    ("vfp4", Some("arm_target_feature")),
+];
+
+const AARCH64_WHITELIST: &[(&str, Option<&str>)] = &[
+    ("fp", Some("aarch64_target_feature")),
+    ("neon", Some("aarch64_target_feature")),
+    ("sve", Some("aarch64_target_feature")),
+    ("crc", Some("aarch64_target_feature")),
+    ("crypto", Some("aarch64_target_feature")),
+    ("ras", Some("aarch64_target_feature")),
+    ("lse", Some("aarch64_target_feature")),
+    ("rdm", Some("aarch64_target_feature")),
+    ("fp16", Some("aarch64_target_feature")),
+    ("rcpc", Some("aarch64_target_feature")),
+    ("dotprod", Some("aarch64_target_feature")),
+    ("v8.1a", Some("aarch64_target_feature")),
+    ("v8.2a", Some("aarch64_target_feature")),
+    ("v8.3a", Some("aarch64_target_feature")),
+];
+
+const X86_WHITELIST: &[(&str, Option<&str>)] = &[
+    ("aes", None),
+    ("avx", None),
+    ("avx2", None),
+    ("avx512bw", Some("avx512_target_feature")),
+    ("avx512cd", Some("avx512_target_feature")),
+    ("avx512dq", Some("avx512_target_feature")),
+    ("avx512er", Some("avx512_target_feature")),
+    ("avx512f", Some("avx512_target_feature")),
+    ("avx512ifma", Some("avx512_target_feature")),
+    ("avx512pf", Some("avx512_target_feature")),
+    ("avx512vbmi", Some("avx512_target_feature")),
+    ("avx512vl", Some("avx512_target_feature")),
+    ("avx512vpopcntdq", Some("avx512_target_feature")),
+    ("bmi1", None),
+    ("bmi2", None),
+    ("fma", None),
+    ("fxsr", None),
+    ("lzcnt", None),
+    ("mmx", Some("mmx_target_feature")),
+    ("pclmulqdq", None),
+    ("popcnt", None),
+    ("rdrand", None),
+    ("rdseed", None),
+    ("sha", None),
+    ("sse", None),
+    ("sse2", None),
+    ("sse3", None),
+    ("sse4.1", None),
+    ("sse4.2", None),
+    ("sse4a", Some("sse4a_target_feature")),
+    ("ssse3", None),
+    ("tbm", Some("tbm_target_feature")),
+    ("xsave", None),
+    ("xsavec", None),
+    ("xsaveopt", None),
+    ("xsaves", None),
+];
+
+const HEXAGON_WHITELIST: &[(&str, Option<&str>)] = &[
+    ("hvx", Some("hexagon_target_feature")),
+    ("hvx-double", Some("hexagon_target_feature")),
+];
+
+const POWERPC_WHITELIST: &[(&str, Option<&str>)] = &[
+    ("altivec", Some("powerpc_target_feature")),
+    ("power8-altivec", Some("powerpc_target_feature")),
+    ("power9-altivec", Some("powerpc_target_feature")),
+    ("power8-vector", Some("powerpc_target_feature")),
+    ("power9-vector", Some("powerpc_target_feature")),
+    ("vsx", Some("powerpc_target_feature")),
+];
+
+const MIPS_WHITELIST: &[(&str, Option<&str>)] = &[
+    ("fp64", Some("mips_target_feature")),
+    ("msa", Some("mips_target_feature")),
+];
+
+/// When rustdoc is running, provide a list of all known features so that all their respective
+/// primtives may be documented.
+///
+/// IMPORTANT: If you're adding another whitelist to the above lists, make sure to add it to this
+/// iterator!
+pub fn all_known_features() -> impl Iterator<Item=(&'static str, Option<&'static str>)> {
+    ARM_WHITELIST.iter().cloned()
+        .chain(AARCH64_WHITELIST.iter().cloned())
+        .chain(X86_WHITELIST.iter().cloned())
+        .chain(HEXAGON_WHITELIST.iter().cloned())
+        .chain(POWERPC_WHITELIST.iter().cloned())
+        .chain(MIPS_WHITELIST.iter().cloned())
+}
+
 pub fn to_llvm_feature<'a>(sess: &Session, s: &'a str) -> &'a str {
     let arch = if sess.target.target.arch == "x86_64" {
         "x86"
@@ -116,6 +216,20 @@ pub fn target_features(sess: &Session) -> Vec<Symbol> {
         .map(|feature| Symbol::intern(feature)).collect()
 }
 
+pub fn target_feature_whitelist(sess: &Session)
+    -> &'static [(&'static str, Option<&'static str>)]
+{
+    match &*sess.target.target.arch {
+        "arm" => ARM_WHITELIST,
+        "aarch64" => AARCH64_WHITELIST,
+        "x86" | "x86_64" => X86_WHITELIST,
+        "hexagon" => HEXAGON_WHITELIST,
+        "mips" | "mips64" => MIPS_WHITELIST,
+        "powerpc" | "powerpc64" => POWERPC_WHITELIST,
+        _ => &[],
+    }
+}
+
 pub fn print_version() {
     // Can be called without initializing LLVM
     unsafe {
diff --git a/src/librustc_codegen_utils/codegen_backend.rs b/src/librustc_codegen_utils/codegen_backend.rs
index 8043559b3109..3cbf176d98bc 100644
--- a/src/librustc_codegen_utils/codegen_backend.rs
+++ b/src/librustc_codegen_utils/codegen_backend.rs
@@ -42,6 +42,7 @@ use rustc::middle::cstore::EncodedMetadata;
 use rustc::middle::cstore::MetadataLoader;
 use rustc::dep_graph::DepGraph;
 use rustc_target::spec::Target;
+use rustc_data_structures::fx::FxHashMap;
 use rustc_mir::monomorphize::collector;
 use link::{build_link_meta, out_filename};
 
@@ -132,9 +133,7 @@ impl CodegenBackend for MetadataOnlyCodegenBackend {
         ::symbol_names::provide(providers);
 
         providers.target_features_whitelist = |_tcx, _cnum| {
-            Lrc::new(::llvm_target_features::all_known_features()
-                .map(|(a, b)| (a.to_string(), b.map(|s| s.to_string())))
-                .collect())
+            Lrc::new(FxHashMap()) // Just a dummy
         };
         providers.is_reachable_non_generic = |_tcx, _defid| true;
         providers.exported_symbols = |_tcx, _crate| Arc::new(Vec::new());
diff --git a/src/librustc_codegen_utils/lib.rs b/src/librustc_codegen_utils/lib.rs
index 4ac0e3591b3c..f59cf5832fcb 100644
--- a/src/librustc_codegen_utils/lib.rs
+++ b/src/librustc_codegen_utils/lib.rs
@@ -44,7 +44,6 @@ pub mod link;
 pub mod codegen_backend;
 pub mod symbol_names;
 pub mod symbol_names_test;
-pub mod llvm_target_features;
 
 /// check for the #[rustc_error] annotation, which forces an
 /// error in codegen. This is used to write compile-fail tests
diff --git a/src/librustc_codegen_utils/llvm_target_features.rs b/src/librustc_codegen_utils/llvm_target_features.rs
deleted file mode 100644
index 8e11363cead8..000000000000
--- a/src/librustc_codegen_utils/llvm_target_features.rs
+++ /dev/null
@@ -1,127 +0,0 @@
-// Copyright 2017 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 rustc::session::Session;
-
-// WARNING: the features after applying `to_llvm_feature` must be known
-// to LLVM or the feature detection code will walk past the end of the feature
-// array, leading to crashes.
-
-const ARM_WHITELIST: &[(&str, Option<&str>)] = &[
-    ("mclass", Some("arm_target_feature")),
-    ("neon", Some("arm_target_feature")),
-    ("v7", Some("arm_target_feature")),
-    ("vfp2", Some("arm_target_feature")),
-    ("vfp3", Some("arm_target_feature")),
-    ("vfp4", Some("arm_target_feature")),
-];
-
-const AARCH64_WHITELIST: &[(&str, Option<&str>)] = &[
-    ("fp", Some("aarch64_target_feature")),
-    ("neon", Some("aarch64_target_feature")),
-    ("sve", Some("aarch64_target_feature")),
-    ("crc", Some("aarch64_target_feature")),
-    ("crypto", Some("aarch64_target_feature")),
-    ("ras", Some("aarch64_target_feature")),
-    ("lse", Some("aarch64_target_feature")),
-    ("rdm", Some("aarch64_target_feature")),
-    ("fp16", Some("aarch64_target_feature")),
-    ("rcpc", Some("aarch64_target_feature")),
-    ("dotprod", Some("aarch64_target_feature")),
-    ("v8.1a", Some("aarch64_target_feature")),
-    ("v8.2a", Some("aarch64_target_feature")),
-    ("v8.3a", Some("aarch64_target_feature")),
-];
-
-const X86_WHITELIST: &[(&str, Option<&str>)] = &[
-    ("aes", None),
-    ("avx", None),
-    ("avx2", None),
-    ("avx512bw", Some("avx512_target_feature")),
-    ("avx512cd", Some("avx512_target_feature")),
-    ("avx512dq", Some("avx512_target_feature")),
-    ("avx512er", Some("avx512_target_feature")),
-    ("avx512f", Some("avx512_target_feature")),
-    ("avx512ifma", Some("avx512_target_feature")),
-    ("avx512pf", Some("avx512_target_feature")),
-    ("avx512vbmi", Some("avx512_target_feature")),
-    ("avx512vl", Some("avx512_target_feature")),
-    ("avx512vpopcntdq", Some("avx512_target_feature")),
-    ("bmi1", None),
-    ("bmi2", None),
-    ("fma", None),
-    ("fxsr", None),
-    ("lzcnt", None),
-    ("mmx", Some("mmx_target_feature")),
-    ("pclmulqdq", None),
-    ("popcnt", None),
-    ("rdrand", None),
-    ("rdseed", None),
-    ("sha", None),
-    ("sse", None),
-    ("sse2", None),
-    ("sse3", None),
-    ("sse4.1", None),
-    ("sse4.2", None),
-    ("sse4a", Some("sse4a_target_feature")),
-    ("ssse3", None),
-    ("tbm", Some("tbm_target_feature")),
-    ("xsave", None),
-    ("xsavec", None),
-    ("xsaveopt", None),
-    ("xsaves", None),
-];
-
-const HEXAGON_WHITELIST: &[(&str, Option<&str>)] = &[
-    ("hvx", Some("hexagon_target_feature")),
-    ("hvx-double", Some("hexagon_target_feature")),
-];
-
-const POWERPC_WHITELIST: &[(&str, Option<&str>)] = &[
-    ("altivec", Some("powerpc_target_feature")),
-    ("power8-altivec", Some("powerpc_target_feature")),
-    ("power9-altivec", Some("powerpc_target_feature")),
-    ("power8-vector", Some("powerpc_target_feature")),
-    ("power9-vector", Some("powerpc_target_feature")),
-    ("vsx", Some("powerpc_target_feature")),
-];
-
-const MIPS_WHITELIST: &[(&str, Option<&str>)] = &[
-    ("fp64", Some("mips_target_feature")),
-    ("msa", Some("mips_target_feature")),
-];
-
-/// When rustdoc is running, provide a list of all known features so that all their respective
-/// primtives may be documented.
-///
-/// IMPORTANT: If you're adding another whitelist to the above lists, make sure to add it to this
-/// iterator!
-pub fn all_known_features() -> impl Iterator<Item=(&'static str, Option<&'static str>)> {
-    ARM_WHITELIST.iter().cloned()
-        .chain(AARCH64_WHITELIST.iter().cloned())
-        .chain(X86_WHITELIST.iter().cloned())
-        .chain(HEXAGON_WHITELIST.iter().cloned())
-        .chain(POWERPC_WHITELIST.iter().cloned())
-        .chain(MIPS_WHITELIST.iter().cloned())
-}
-
-pub fn target_feature_whitelist(sess: &Session)
-    -> &'static [(&'static str, Option<&'static str>)]
-{
-    match &*sess.target.target.arch {
-        "arm" => ARM_WHITELIST,
-        "aarch64" => AARCH64_WHITELIST,
-        "x86" | "x86_64" => X86_WHITELIST,
-        "hexagon" => HEXAGON_WHITELIST,
-        "mips" | "mips64" => MIPS_WHITELIST,
-        "powerpc" | "powerpc64" => POWERPC_WHITELIST,
-        _ => &[],
-    }
-}

From a5330415aa4b85ede7ca6a32fdad1c27ca5056a5 Mon Sep 17 00:00:00 2001
From: bjorn3 <bjorn3@users.noreply.github.com>
Date: Sat, 23 Jun 2018 17:23:04 +0200
Subject: [PATCH 16/19] Only use coresimd when codegen_backend is LLVM

---
 src/bootstrap/bin/rustc.rs     |  7 +++++++
 src/bootstrap/builder.rs       |  4 ++++
 src/libcore/lib.rs             |  7 ++++---
 src/librustc/session/config.rs | 12 ++++++++++++
 src/libstd/lib.rs              |  8 ++++----
 5 files changed, 31 insertions(+), 7 deletions(-)

diff --git a/src/bootstrap/bin/rustc.rs b/src/bootstrap/bin/rustc.rs
index 4607ca5cf9f4..98fec4c4861f 100644
--- a/src/bootstrap/bin/rustc.rs
+++ b/src/bootstrap/bin/rustc.rs
@@ -107,6 +107,13 @@ fn main() {
              env::join_paths(&dylib_path).unwrap());
     let mut maybe_crate = None;
 
+    // Don't use metadata only backend for snapshot compiler, because it may be broken
+    if env::var("RUSTC_SHOULD_USE_METADATA_ONLY_BACKEND").is_ok() && stage != "0" {
+        //cmd.arg("-Zcodegen-backend=metadata_only");
+    } else {
+        cmd.arg("--cfg").arg("codegen_backend=\"llvm\"");
+    }
+
     // Print backtrace in case of ICE
     if env::var("RUSTC_BACKTRACE_ON_ICE").is_ok() && env::var("RUST_BACKTRACE").is_err() {
         cmd.env("RUST_BACKTRACE", "1");
diff --git a/src/bootstrap/builder.rs b/src/bootstrap/builder.rs
index d2f9b2653d50..7e4a12f7310f 100644
--- a/src/bootstrap/builder.rs
+++ b/src/bootstrap/builder.rs
@@ -747,6 +747,10 @@ impl<'a> Builder<'a> {
             stage = compiler.stage;
         }
 
+        if self.config.rust_codegen_backends.is_empty() {
+            cargo.env("RUSTC_SHOULD_USE_METADATA_ONLY_BACKEND", "1");
+        }
+
         let mut extra_args = env::var(&format!("RUSTFLAGS_STAGE_{}", stage)).unwrap_or_default();
         if stage != 0 {
             let s = env::var("RUSTFLAGS_STAGE_NOT_0").unwrap_or_default();
diff --git a/src/libcore/lib.rs b/src/libcore/lib.rs
index bbe6ae8619fe..0971f50913cb 100644
--- a/src/libcore/lib.rs
+++ b/src/libcore/lib.rs
@@ -241,12 +241,13 @@ macro_rules! vector_impl { ($([$f:ident, $($args:tt)*]),*) => { $($f!($($args)*)
 #[path = "../stdsimd/coresimd/mod.rs"]
 #[allow(missing_docs, missing_debug_implementations, dead_code, unused_imports)]
 #[unstable(feature = "stdsimd", issue = "48556")]
-#[cfg(not(stage0))] // allow changes to how stdsimd works in stage0
+// allow changes to how stdsimd works in stage0 and don't use whithout LLVM
+#[cfg(all(not(stage0), codegen_backend="llvm"))]
 mod coresimd;
 
 #[unstable(feature = "stdsimd", issue = "48556")]
-#[cfg(not(stage0))]
+#[cfg(all(not(stage0), codegen_backend="llvm"))]
 pub use coresimd::simd;
 #[stable(feature = "simd_arch", since = "1.27.0")]
-#[cfg(not(stage0))]
+#[cfg(all(not(stage0), codegen_backend="llvm"))]
 pub use coresimd::arch;
diff --git a/src/librustc/session/config.rs b/src/librustc/session/config.rs
index 95c68214ec7c..05e08cb7973a 100644
--- a/src/librustc/session/config.rs
+++ b/src/librustc/session/config.rs
@@ -1418,6 +1418,18 @@ pub fn default_configuration(sess: &Session) -> ast::CrateConfig {
     if sess.opts.crate_types.contains(&CrateTypeProcMacro) {
         ret.insert((Symbol::intern("proc_macro"), None));
     }
+    /*if nightly_options::is_nightly_build() {
+        let backend_name = sess.opts
+            .debugging_opts
+            .codegen_backend
+            .as_ref()
+            .map(|s| s as &str)
+            .unwrap_or("llvm");
+        ret.insert((
+            Symbol::intern("codegen_backend"),
+            Some(Symbol::intern(backend_name)),
+        ));
+    }*/
     return ret;
 }
 
diff --git a/src/libstd/lib.rs b/src/libstd/lib.rs
index d73cb1f8349a..d79f851a3d76 100644
--- a/src/libstd/lib.rs
+++ b/src/libstd/lib.rs
@@ -523,22 +523,22 @@ pub mod rt;
 #[path = "../stdsimd/stdsimd/mod.rs"]
 #[allow(missing_debug_implementations, missing_docs, dead_code)]
 #[unstable(feature = "stdsimd", issue = "48556")]
-#[cfg(all(not(stage0), not(test)))]
+#[cfg(all(not(stage0), not(test), codegen_backend="llvm"))]
 mod stdsimd;
 
 // A "fake" module needed by the `stdsimd` module to compile, not actually
 // exported though.
-#[cfg(not(stage0))]
+#[cfg(all(not(stage0), codegen_backend="llvm"))]
 mod coresimd {
     pub use core::arch;
     pub use core::simd;
 }
 
 #[unstable(feature = "stdsimd", issue = "48556")]
-#[cfg(all(not(stage0), not(test)))]
+#[cfg(all(not(stage0), not(test), codegen_backend="llvm"))]
 pub use stdsimd::simd;
 #[stable(feature = "simd_arch", since = "1.27.0")]
-#[cfg(all(not(stage0), not(test)))]
+#[cfg(all(not(stage0), not(test), codegen_backend="llvm"))]
 pub use stdsimd::arch;
 
 // Include a number of private modules that exist solely to provide

From 163cb572a491cb3eb7f2c792415c93840cb7e9c0 Mon Sep 17 00:00:00 2001
From: bjorn3 <bjorn3@users.noreply.github.com>
Date: Sun, 24 Jun 2018 13:32:33 +0200
Subject: [PATCH 17/19] Hopefully fix it

---
 src/bootstrap/bin/rustc.rs | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/src/bootstrap/bin/rustc.rs b/src/bootstrap/bin/rustc.rs
index 98fec4c4861f..04882426fd8e 100644
--- a/src/bootstrap/bin/rustc.rs
+++ b/src/bootstrap/bin/rustc.rs
@@ -108,9 +108,7 @@ fn main() {
     let mut maybe_crate = None;
 
     // Don't use metadata only backend for snapshot compiler, because it may be broken
-    if env::var("RUSTC_SHOULD_USE_METADATA_ONLY_BACKEND").is_ok() && stage != "0" {
-        //cmd.arg("-Zcodegen-backend=metadata_only");
-    } else {
+    if env::var("RUSTC_SHOULD_USE_METADATA_ONLY_BACKEND").is_err() {
         cmd.arg("--cfg").arg("codegen_backend=\"llvm\"");
     }
 

From ff12beb8756f028d44f898a91960ed70102a4792 Mon Sep 17 00:00:00 2001
From: bjorn3 <bjorn3@users.noreply.github.com>
Date: Sat, 30 Jun 2018 10:45:14 +0200
Subject: [PATCH 18/19] Revert changes to bootstrap, rustc_driver and fix
 {core,std}simd

---
 config.toml.example            |  8 ++++++--
 src/bootstrap/bin/rustc.rs     |  5 -----
 src/bootstrap/builder.rs       |  6 +-----
 src/bootstrap/compile.rs       | 27 +++++++++++++--------------
 src/bootstrap/config.rs        |  4 ++++
 src/bootstrap/test.rs          |  4 ++--
 src/bootstrap/tool.rs          |  2 +-
 src/libcore/lib.rs             |  7 +++----
 src/librustc/session/config.rs | 12 ------------
 src/librustc_driver/lib.rs     | 14 ++------------
 src/libstd/lib.rs              |  8 ++++----
 11 files changed, 36 insertions(+), 61 deletions(-)

diff --git a/config.toml.example b/config.toml.example
index 0de2cce5679d..0578f929224d 100644
--- a/config.toml.example
+++ b/config.toml.example
@@ -14,6 +14,10 @@
 # =============================================================================
 [llvm]
 
+# Indicates whether rustc will support compilation with LLVM
+# note: rustc does not compile without LLVM at the moment
+#enabled = true
+
 # Indicates whether the LLVM build is a Release or Debug build
 #optimize = true
 
@@ -330,8 +334,8 @@
 # This is an array of the codegen backends that will be compiled for the rustc
 # that's being compiled. The default is to only build the LLVM codegen backend,
 # but you can also optionally enable the "emscripten" backend for asm.js or
-# make this an empty array (which will disable LLVM, but that probably won't
-# get too far in the bootstrap)
+# make this an empty array (but that probably won't get too far in the
+# bootstrap)
 #codegen-backends = ["llvm"]
 
 # This is the name of the directory in which codegen backends will get installed
diff --git a/src/bootstrap/bin/rustc.rs b/src/bootstrap/bin/rustc.rs
index 04882426fd8e..4607ca5cf9f4 100644
--- a/src/bootstrap/bin/rustc.rs
+++ b/src/bootstrap/bin/rustc.rs
@@ -107,11 +107,6 @@ fn main() {
              env::join_paths(&dylib_path).unwrap());
     let mut maybe_crate = None;
 
-    // Don't use metadata only backend for snapshot compiler, because it may be broken
-    if env::var("RUSTC_SHOULD_USE_METADATA_ONLY_BACKEND").is_err() {
-        cmd.arg("--cfg").arg("codegen_backend=\"llvm\"");
-    }
-
     // Print backtrace in case of ICE
     if env::var("RUSTC_BACKTRACE_ON_ICE").is_ok() && env::var("RUST_BACKTRACE").is_err() {
         cmd.env("RUST_BACKTRACE", "1");
diff --git a/src/bootstrap/builder.rs b/src/bootstrap/builder.rs
index 7e4a12f7310f..fad0a553802a 100644
--- a/src/bootstrap/builder.rs
+++ b/src/bootstrap/builder.rs
@@ -747,10 +747,6 @@ impl<'a> Builder<'a> {
             stage = compiler.stage;
         }
 
-        if self.config.rust_codegen_backends.is_empty() {
-            cargo.env("RUSTC_SHOULD_USE_METADATA_ONLY_BACKEND", "1");
-        }
-
         let mut extra_args = env::var(&format!("RUSTFLAGS_STAGE_{}", stage)).unwrap_or_default();
         if stage != 0 {
             let s = env::var("RUSTFLAGS_STAGE_NOT_0").unwrap_or_default();
@@ -897,7 +893,7 @@ impl<'a> Builder<'a> {
         //
         // If LLVM support is disabled we need to use the snapshot compiler to compile
         // build scripts, as the new compiler doesn't support executables.
-        if mode == Mode::Std || self.config.rust_codegen_backends.is_empty() {
+        if mode == Mode::Std || !self.config.llvm_enabled {
             cargo
                 .env("RUSTC_SNAPSHOT", &self.initial_rustc)
                 .env("RUSTC_SNAPSHOT_LIBDIR", self.rustc_snapshot_libdir());
diff --git a/src/bootstrap/compile.rs b/src/bootstrap/compile.rs
index 524df9587dad..298bd58c6cdf 100644
--- a/src/bootstrap/compile.rs
+++ b/src/bootstrap/compile.rs
@@ -182,13 +182,11 @@ pub fn std_cargo(builder: &Builder,
             // missing
             // We also only build the runtimes when --enable-sanitizers (or its
             // config.toml equivalent) is used
-            if !builder.config.rust_codegen_backends.is_empty() {
-                let llvm_config = builder.ensure(native::Llvm {
-                    target: builder.config.build,
-                    emscripten: false,
-                });
-                cargo.env("LLVM_CONFIG", llvm_config);
-            }
+            let llvm_config = builder.ensure(native::Llvm {
+                target: builder.config.build,
+                emscripten: false,
+            });
+            cargo.env("LLVM_CONFIG", llvm_config);
         }
 
         cargo.arg("--features").arg(features)
@@ -645,13 +643,14 @@ impl Step for CodegenBackend {
 
     fn make_run(run: RunConfig) {
         let backend = run.builder.config.rust_codegen_backends.get(0);
-        if let Some(backend) = backend.cloned() {
-            run.builder.ensure(CodegenBackend {
-                compiler: run.builder.compiler(run.builder.top_stage, run.host),
-                target: run.target,
-                backend,
-            });
-        }
+        let backend = backend.cloned().unwrap_or_else(|| {
+            INTERNER.intern_str("llvm")
+        });
+        run.builder.ensure(CodegenBackend {
+            compiler: run.builder.compiler(run.builder.top_stage, run.host),
+            target: run.target,
+            backend,
+        });
     }
 
     fn run(self, builder: &Builder) {
diff --git a/src/bootstrap/config.rs b/src/bootstrap/config.rs
index 2e629456b7ef..b3ed10257bda 100644
--- a/src/bootstrap/config.rs
+++ b/src/bootstrap/config.rs
@@ -74,6 +74,7 @@ pub struct Config {
     pub backtrace_on_ice: bool,
 
     // llvm codegen options
+    pub llvm_enabled: bool,
     pub llvm_assertions: bool,
     pub llvm_optimize: bool,
     pub llvm_release_debuginfo: bool,
@@ -238,6 +239,7 @@ struct Install {
 #[derive(Deserialize, Default)]
 #[serde(deny_unknown_fields, rename_all = "kebab-case")]
 struct Llvm {
+    enabled: Option<bool>,
     ccache: Option<StringOrBool>,
     ninja: Option<bool>,
     assertions: Option<bool>,
@@ -339,6 +341,7 @@ impl Config {
 
     pub fn default_opts() -> Config {
         let mut config = Config::default();
+        config.llvm_enabled = true;
         config.llvm_optimize = true;
         config.llvm_version_check = true;
         config.use_jemalloc = true;
@@ -493,6 +496,7 @@ impl Config {
                 Some(StringOrBool::Bool(false)) | None => {}
             }
             set(&mut config.ninja, llvm.ninja);
+            set(&mut config.llvm_enabled, llvm.enabled);
             llvm_assertions = llvm.assertions;
             set(&mut config.llvm_optimize, llvm.optimize);
             set(&mut config.llvm_release_debuginfo, llvm.release_debuginfo);
diff --git a/src/bootstrap/test.rs b/src/bootstrap/test.rs
index 917b85690dea..6254f9816566 100644
--- a/src/bootstrap/test.rs
+++ b/src/bootstrap/test.rs
@@ -1096,7 +1096,7 @@ impl Step for Compiletest {
             cmd.arg("--quiet");
         }
 
-        if !builder.config.rust_codegen_backends.is_empty() {
+        if builder.config.llvm_enabled {
             let llvm_config = builder.ensure(native::Llvm {
                 target: builder.config.build,
                 emscripten: false,
@@ -1129,7 +1129,7 @@ impl Step for Compiletest {
                 }
             }
         }
-        if suite == "run-make-fulldeps" && builder.config.rust_codegen_backends.is_empty() {
+        if suite == "run-make-fulldeps" && !builder.config.llvm_enabled {
             builder.info(&format!(
                 "Ignoring run-make test suite as they generally don't work without LLVM"
             ));
diff --git a/src/bootstrap/tool.rs b/src/bootstrap/tool.rs
index 640dd9ecdd99..b3d7b9a91ecf 100644
--- a/src/bootstrap/tool.rs
+++ b/src/bootstrap/tool.rs
@@ -672,7 +672,7 @@ impl<'a> Builder<'a> {
     }
 
     fn llvm_bin_path(&self) -> Option<PathBuf> {
-        if !self.config.rust_codegen_backends.is_empty() && !self.config.dry_run {
+        if self.config.llvm_enabled && !self.config.dry_run {
             let llvm_config = self.ensure(native::Llvm {
                 target: self.config.build,
                 emscripten: false,
diff --git a/src/libcore/lib.rs b/src/libcore/lib.rs
index 0971f50913cb..bbe6ae8619fe 100644
--- a/src/libcore/lib.rs
+++ b/src/libcore/lib.rs
@@ -241,13 +241,12 @@ macro_rules! vector_impl { ($([$f:ident, $($args:tt)*]),*) => { $($f!($($args)*)
 #[path = "../stdsimd/coresimd/mod.rs"]
 #[allow(missing_docs, missing_debug_implementations, dead_code, unused_imports)]
 #[unstable(feature = "stdsimd", issue = "48556")]
-// allow changes to how stdsimd works in stage0 and don't use whithout LLVM
-#[cfg(all(not(stage0), codegen_backend="llvm"))]
+#[cfg(not(stage0))] // allow changes to how stdsimd works in stage0
 mod coresimd;
 
 #[unstable(feature = "stdsimd", issue = "48556")]
-#[cfg(all(not(stage0), codegen_backend="llvm"))]
+#[cfg(not(stage0))]
 pub use coresimd::simd;
 #[stable(feature = "simd_arch", since = "1.27.0")]
-#[cfg(all(not(stage0), codegen_backend="llvm"))]
+#[cfg(not(stage0))]
 pub use coresimd::arch;
diff --git a/src/librustc/session/config.rs b/src/librustc/session/config.rs
index 05e08cb7973a..95c68214ec7c 100644
--- a/src/librustc/session/config.rs
+++ b/src/librustc/session/config.rs
@@ -1418,18 +1418,6 @@ pub fn default_configuration(sess: &Session) -> ast::CrateConfig {
     if sess.opts.crate_types.contains(&CrateTypeProcMacro) {
         ret.insert((Symbol::intern("proc_macro"), None));
     }
-    /*if nightly_options::is_nightly_build() {
-        let backend_name = sess.opts
-            .debugging_opts
-            .codegen_backend
-            .as_ref()
-            .map(|s| s as &str)
-            .unwrap_or("llvm");
-        ret.insert((
-            Symbol::intern("codegen_backend"),
-            Some(Symbol::intern(backend_name)),
-        ));
-    }*/
     return ret;
 }
 
diff --git a/src/librustc_driver/lib.rs b/src/librustc_driver/lib.rs
index 321d398b5210..84f7b35d21f3 100644
--- a/src/librustc_driver/lib.rs
+++ b/src/librustc_driver/lib.rs
@@ -375,20 +375,10 @@ fn get_codegen_sysroot(backend_name: &str) -> fn() -> Box<CodegenBackend> {
     match file {
         Some(ref s) => return load_backend_from_dylib(s),
         None => {
-            if !::rustc::session::config::nightly_options::is_nightly_build() {
-                let err = format!("failed to load default codegen backend for `{}`, \
+            let err = format!("failed to load default codegen backend for `{}`, \
                                no appropriate codegen dylib found in `{}`",
                                backend_name, sysroot.display());
-                early_error(ErrorOutputType::default(), &err);
-            } else {
-                let warn = format!("no codegen-backend `{}`, \
-                               no appropriate dylib in `{}`. \
-                               Falling back to metadata_only codegen backend. \
-                               **This is suitable for dev purposes only**",
-                               backend_name, sysroot.display());
-                early_warn(ErrorOutputType::default(), &warn);
-                return rustc_codegen_utils::codegen_backend::MetadataOnlyCodegenBackend::new;
-            }
+            early_error(ErrorOutputType::default(), &err);
         }
     }
 
diff --git a/src/libstd/lib.rs b/src/libstd/lib.rs
index d79f851a3d76..d73cb1f8349a 100644
--- a/src/libstd/lib.rs
+++ b/src/libstd/lib.rs
@@ -523,22 +523,22 @@ pub mod rt;
 #[path = "../stdsimd/stdsimd/mod.rs"]
 #[allow(missing_debug_implementations, missing_docs, dead_code)]
 #[unstable(feature = "stdsimd", issue = "48556")]
-#[cfg(all(not(stage0), not(test), codegen_backend="llvm"))]
+#[cfg(all(not(stage0), not(test)))]
 mod stdsimd;
 
 // A "fake" module needed by the `stdsimd` module to compile, not actually
 // exported though.
-#[cfg(all(not(stage0), codegen_backend="llvm"))]
+#[cfg(not(stage0))]
 mod coresimd {
     pub use core::arch;
     pub use core::simd;
 }
 
 #[unstable(feature = "stdsimd", issue = "48556")]
-#[cfg(all(not(stage0), not(test), codegen_backend="llvm"))]
+#[cfg(all(not(stage0), not(test)))]
 pub use stdsimd::simd;
 #[stable(feature = "simd_arch", since = "1.27.0")]
-#[cfg(all(not(stage0), not(test), codegen_backend="llvm"))]
+#[cfg(all(not(stage0), not(test)))]
 pub use stdsimd::arch;
 
 // Include a number of private modules that exist solely to provide

From 23c0b3b75c865f18e452e42680247502961778b9 Mon Sep 17 00:00:00 2001
From: bjorn3 <bjorn3@users.noreply.github.com>
Date: Sat, 7 Jul 2018 11:05:21 +0200
Subject: [PATCH 19/19] Update Cargo.lock

---
 src/Cargo.lock | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/src/Cargo.lock b/src/Cargo.lock
index e3610c1d679b..d91a165e5373 100644
--- a/src/Cargo.lock
+++ b/src/Cargo.lock
@@ -57,11 +57,6 @@ dependencies = [
  "winapi 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
-[[package]]
-name = "ar"
-version = "0.3.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
 [[package]]
 name = "arena"
 version = "0.0.0"
@@ -2031,6 +2026,7 @@ dependencies = [
 name = "rustc_codegen_utils"
 version = "0.0.0"
 dependencies = [
+ "flate2 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc 0.0.0",
  "rustc_data_structures 0.0.0",
@@ -2070,7 +2066,6 @@ dependencies = [
 name = "rustc_driver"
 version = "0.0.0"
 dependencies = [
- "ar 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "arena 0.0.0",
  "env_logger 0.5.10 (registry+https://github.com/rust-lang/crates.io-index)",
  "graphviz 0.0.0",
@@ -3075,7 +3070,6 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum aho-corasick 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)" = "f0ba20154ea1f47ce2793322f049c5646cc6d0fa9759d5f333f286e507bf8080"
 "checksum ammonia 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "fd4c682378117e4186a492b2252b9537990e1617f44aed9788b9a1149de45477"
 "checksum ansi_term 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ee49baf6cb617b853aa8d93bf420db2383fab46d314482ca2803b40d5fde979b"
-"checksum ar 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "35c7a5669cb64f085739387e1308b74e6d44022464b7f1b63bbd4ceb6379ec31"
 "checksum arrayvec 0.4.7 (registry+https://github.com/rust-lang/crates.io-index)" = "a1e964f9e24d588183fcb43503abda40d288c8657dfc27311516ce2f05675aef"
 "checksum assert_cli 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)" = "98589b0e465a6c510d95fceebd365bb79bedece7f6e18a480897f2015f85ec51"
 "checksum atty 0.2.10 (registry+https://github.com/rust-lang/crates.io-index)" = "2fc4a1aa4c24c0718a250f0681885c1af91419d242f29eb8f2ab28502d80dbd1"