Auto merge of #54911 - ljedrz:cleanup_codegen_llvm_top, r=michaelwoerister

Cleanup top-level codegen_llvm

- improve allocations
- improve common patterns
- remove explicit returns
- fix spelling & grammatical errors
- whitespace & formatting improvements

src/librustc_codegen_llvm/abi.rs

@@ -150,7 +150,7 @@ impl LlvmType for CastTarget {
         // Create list of fields in the main structure
         let mut args: Vec<_> =
             self.prefix.iter().flat_map(|option_kind| option_kind.map(
-                    |kind| Reg { kind: kind, size: self.prefix_chunk }.llvm_type(cx)))
+                |kind| Reg { kind: kind, size: self.prefix_chunk }.llvm_type(cx)))
             .chain((0..rest_count).map(|_| rest_ll_unit))
             .collect();
 
@@ -259,8 +259,7 @@ impl ArgTypeExt<'ll, 'tcx> for ArgType<'tcx, Ty<'tcx>> {
 }
 
 pub trait FnTypeExt<'tcx> {
-    fn of_instance(cx: &CodegenCx<'ll, 'tcx>, instance: &ty::Instance<'tcx>)
+    fn of_instance(cx: &CodegenCx<'ll, 'tcx>, instance: &ty::Instance<'tcx>) -> Self;
-                   -> Self;
     fn new(cx: &CodegenCx<'ll, 'tcx>,
            sig: ty::FnSig<'tcx>,
            extra_args: &[Ty<'tcx>]) -> Self;
@@ -283,8 +282,7 @@ pub trait FnTypeExt<'tcx> {
 }
 
 impl<'tcx> FnTypeExt<'tcx> for FnType<'tcx, Ty<'tcx>> {
-    fn of_instance(cx: &CodegenCx<'ll, 'tcx>, instance: &ty::Instance<'tcx>)
+    fn of_instance(cx: &CodegenCx<'ll, 'tcx>, instance: &ty::Instance<'tcx>) -> Self {
-                       -> Self {
         let fn_ty = instance.ty(cx.tcx);
         let sig = ty_fn_sig(cx, fn_ty);
         let sig = cx.tcx.normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), &sig);
@@ -292,16 +290,16 @@ impl<'tcx> FnTypeExt<'tcx> for FnType<'tcx, Ty<'tcx>> {
     }
 
     fn new(cx: &CodegenCx<'ll, 'tcx>,
-               sig: ty::FnSig<'tcx>,
+           sig: ty::FnSig<'tcx>,
-               extra_args: &[Ty<'tcx>]) -> Self {
+           extra_args: &[Ty<'tcx>]) -> Self {
         FnType::new_internal(cx, sig, extra_args, |ty, _| {
             ArgType::new(cx.layout_of(ty))
         })
     }
 
     fn new_vtable(cx: &CodegenCx<'ll, 'tcx>,
-                      sig: ty::FnSig<'tcx>,
+                  sig: ty::FnSig<'tcx>,
-                      extra_args: &[Ty<'tcx>]) -> Self {
+                  extra_args: &[Ty<'tcx>]) -> Self {
         FnType::new_internal(cx, sig, extra_args, |ty, arg_idx| {
             let mut layout = cx.layout_of(ty);
             // Don't pass the vtable, it's not an argument of the virtual fn.
@@ -338,7 +336,7 @@ impl<'tcx> FnTypeExt<'tcx> for FnType<'tcx, Ty<'tcx>> {
             RustIntrinsic | PlatformIntrinsic |
             Rust | RustCall => Conv::C,
 
-            // It's the ABI's job to select this, not us.
+            // It's the ABI's job to select this, not ours.
             System => bug!("system abi should be selected elsewhere"),
 
             Stdcall => Conv::X86Stdcall,
@@ -697,14 +695,13 @@ impl<'tcx> FnTypeExt<'tcx> for FnType<'tcx, Ty<'tcx>> {
             // If the value is a boolean, the range is 0..2 and that ultimately
             // become 0..0 when the type becomes i1, which would be rejected
             // by the LLVM verifier.
-            match scalar.value {
+            if let layout::Int(..) = scalar.value {
-                layout::Int(..) if !scalar.is_bool() => {
+                if !scalar.is_bool() {
                     let range = scalar.valid_range_exclusive(bx.cx);
                     if range.start != range.end {
                         bx.range_metadata(callsite, range);
                     }
                 }
-                _ => {}
             }
         }
         for arg in &self.args {

src/librustc_codegen_llvm/allocator.rs

@@ -33,7 +33,7 @@ pub(crate) unsafe fn codegen(tcx: TyCtxt, mods: &ModuleLlvm, kind: AllocatorKind
     let void = llvm::LLVMVoidTypeInContext(llcx);
 
     for method in ALLOCATOR_METHODS {
-        let mut args = Vec::new();
+        let mut args = Vec::with_capacity(method.inputs.len());
         for ty in method.inputs.iter() {
             match *ty {
                 AllocatorTy::Layout => {

src/librustc_codegen_llvm/attributes.rs

@@ -94,9 +94,8 @@ pub fn set_probestack(cx: &CodegenCx<'ll, '_>, llfn: &'ll Value) {
     // Currently stack probes seem somewhat incompatible with the address
     // sanitizer. With asan we're already protected from stack overflow anyway
     // so we don't really need stack probes regardless.
-    match cx.sess().opts.debugging_opts.sanitizer {
+    if let Some(Sanitizer::Address) = cx.sess().opts.debugging_opts.sanitizer {
-        Some(Sanitizer::Address) => return,
+        return
-        _ => {}
     }
 
     // probestack doesn't play nice either with pgo-gen.
@@ -280,12 +279,14 @@ pub fn provide_extern(providers: &mut Providers) {
         // `NativeLibrary` internally contains information about
         // `#[link(wasm_import_module = "...")]` for example.
         let native_libs = tcx.native_libraries(cnum);
-        let mut def_id_to_native_lib = FxHashMap();
+
-        for lib in native_libs.iter() {
+        let def_id_to_native_lib = native_libs.iter().filter_map(|lib|
             if let Some(id) = lib.foreign_module {
-                def_id_to_native_lib.insert(id, lib);
+                Some((id, lib))
+            } else {
+                None
             }
-        }
+        ).collect::<FxHashMap<_, _>>();
 
         let mut ret = FxHashMap();
         for lib in tcx.foreign_modules(cnum).iter() {
@@ -296,10 +297,10 @@ pub fn provide_extern(providers: &mut Providers) {
                 Some(s) => s,
                 None => continue,
             };
-            for id in lib.foreign_items.iter() {
+            ret.extend(lib.foreign_items.iter().map(|id| {
                 assert_eq!(id.krate, cnum);
-                ret.insert(*id, module.to_string());
+                (*id, module.to_string())
-            }
+            }));
         }
 
         Lrc::new(ret)

src/librustc_codegen_llvm/base.rs

@@ -213,8 +213,8 @@ pub fn unsized_info(
                             vtable_ptr.llvm_type(cx))
         }
         _ => bug!("unsized_info: invalid unsizing {:?} -> {:?}",
-                                     source,
+                  source,
-                                     target),
+                  target),
     }
 }
 
@@ -340,11 +340,11 @@ pub fn cast_shift_expr_rhs(
 }
 
 fn cast_shift_rhs<'ll, F, G>(op: hir::BinOpKind,
-                        lhs: &'ll Value,
+                             lhs: &'ll Value,
-                        rhs: &'ll Value,
+                             rhs: &'ll Value,
-                        trunc: F,
+                             trunc: F,
-                        zext: G)
+                             zext: G)
-                        -> &'ll Value
+                             -> &'ll Value
     where F: FnOnce(&'ll Value, &'ll Type) -> &'ll Value,
           G: FnOnce(&'ll Value, &'ll Type) -> &'ll Value
 {
@@ -363,8 +363,8 @@ fn cast_shift_rhs<'ll, F, G>(op: hir::BinOpKind,
         if lhs_sz < rhs_sz {
             trunc(rhs, lhs_llty)
         } else if lhs_sz > rhs_sz {
-            // FIXME (#1877: If shifting by negative
+            // FIXME (#1877: If in the future shifting by negative
-            // values becomes not undefined then this is wrong.
+            // values is no longer undefined then this is wrong.
             zext(rhs, lhs_llty)
         } else {
             rhs
@@ -495,10 +495,8 @@ pub fn codegen_instance<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>, instance: Instance<'
     let sig = common::ty_fn_sig(cx, fn_ty);
     let sig = cx.tcx.normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), &sig);
 
-    let lldecl = match cx.instances.borrow().get(&instance) {
+    let lldecl = cx.instances.borrow().get(&instance).cloned().unwrap_or_else(||
-        Some(&val) => val,
+        bug!("Instance `{:?}` not already declared", instance));
-        None => bug!("Instance `{:?}` not already declared", instance)
-    };
 
     cx.stats.borrow_mut().n_closures += 1;
 
@@ -566,8 +564,8 @@ fn maybe_create_entry_wrapper(cx: &CodegenCx) {
         if declare::get_defined_value(cx, "main").is_some() {
             // FIXME: We should be smart and show a better diagnostic here.
             cx.sess().struct_span_err(sp, "entry symbol `main` defined multiple times")
-                      .help("did you use #[no_mangle] on `fn main`? Use #[start] instead")
+                     .help("did you use #[no_mangle] on `fn main`? Use #[start] instead")
-                      .emit();
+                     .emit();
             cx.sess().abort_if_errors();
             bug!();
         }
@@ -736,9 +734,9 @@ fn determine_cgu_reuse<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
 }
 
 pub fn codegen_crate<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
-                             rx: mpsc::Receiver<Box<dyn Any + Send>>)
+                               rx: mpsc::Receiver<Box<dyn Any + Send>>)
-                             -> OngoingCodegen {
+                               -> OngoingCodegen
-
+{
     check_for_rustc_errors_attr(tcx);
 
     if let Some(true) = tcx.sess.opts.debugging_opts.thinlto {
@@ -803,8 +801,7 @@ pub fn codegen_crate<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
 
     // Run the monomorphization collector and partition the collected items into
     // codegen units.
-    let codegen_units =
+    let codegen_units = tcx.collect_and_partition_mono_items(LOCAL_CRATE).1;
-        tcx.collect_and_partition_mono_items(LOCAL_CRATE).1;
     let codegen_units = (*codegen_units).clone();
 
     // Force all codegen_unit queries so they are already either red or green
@@ -837,12 +834,7 @@ pub fn codegen_crate<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
         .iter()
         .any(|(_, list)| {
             use rustc::middle::dependency_format::Linkage;
-            list.iter().any(|linkage| {
+            list.iter().any(|&linkage| linkage == Linkage::Dynamic)
-                match linkage {
-                    Linkage::Dynamic => true,
-                    _ => false,
-                }
-            })
         });
     let allocator_module = if any_dynamic_crate {
         None
@@ -988,7 +980,7 @@ fn collect_and_partition_mono_items<'a, 'tcx>(
                 if mode_string != "lazy" {
                     let message = format!("Unknown codegen-item collection mode '{}'. \
                                            Falling back to 'lazy' mode.",
-                                           mode_string);
+                                          mode_string);
                     tcx.sess.warn(&message);
                 }
 
@@ -1123,7 +1115,15 @@ impl CrateInfo {
             info.load_wasm_imports(tcx, LOCAL_CRATE);
         }
 
-        for &cnum in tcx.crates().iter() {
+        let crates = tcx.crates();
+
+        let n_crates = crates.len();
+        info.native_libraries.reserve(n_crates);
+        info.crate_name.reserve(n_crates);
+        info.used_crate_source.reserve(n_crates);
+        info.missing_lang_items.reserve(n_crates);
+
+        for &cnum in crates.iter() {
             info.native_libraries.insert(cnum, tcx.native_libraries(cnum));
             info.crate_name.insert(cnum, tcx.crate_name(cnum).to_string());
             info.used_crate_source.insert(cnum, tcx.used_crate_source(cnum));
@@ -1165,11 +1165,12 @@ impl CrateInfo {
     }
 
     fn load_wasm_imports(&mut self, tcx: TyCtxt, cnum: CrateNum) {
-        for (&id, module) in tcx.wasm_import_module_map(cnum).iter() {
+        self.wasm_imports.extend(tcx.wasm_import_module_map(cnum).iter().map(|(&id, module)| {
             let instance = Instance::mono(tcx, id);
             let import_name = tcx.symbol_name(instance);
-            self.wasm_imports.insert(import_name.to_string(), module.clone());
+
-        }
+            (import_name.to_string(), module.clone())
+        }));
     }
 }
 

src/librustc_codegen_llvm/builder.rs

@@ -110,10 +110,10 @@ impl Builder<'a, 'll, 'tcx> {
         }
         if self.cx.sess().count_llvm_insns() {
             *self.cx.stats
-                .borrow_mut()
+                    .borrow_mut()
-                .llvm_insns
+                    .llvm_insns
-                .entry(category.to_string())
+                    .entry(category.to_string())
-                .or_insert(0) += 1;
+                    .or_insert(0) += 1;
         }
     }
 
@@ -735,9 +735,9 @@ impl Builder<'a, 'll, 'tcx> {
     }
 
     pub fn inline_asm_call(&self, asm: *const c_char, cons: *const c_char,
-                         inputs: &[&'ll Value], output: &'ll Type,
+                           inputs: &[&'ll Value], output: &'ll Type,
-                         volatile: bool, alignstack: bool,
+                           volatile: bool, alignstack: bool,
-                         dia: AsmDialect) -> Option<&'ll Value> {
+                           dia: AsmDialect) -> Option<&'ll Value> {
         self.count_insn("inlineasm");
 
         let volatile = if volatile { llvm::True }
@@ -1093,7 +1093,7 @@ impl Builder<'a, 'll, 'tcx> {
     ) -> &'ll Value {
         unsafe {
             llvm::LLVMRustBuildAtomicCmpXchg(self.llbuilder, dst, cmp, src,
-                                         order, failure_order, weak)
+                                             order, failure_order, weak)
         }
     }
     pub fn atomic_rmw(
@@ -1194,7 +1194,7 @@ impl Builder<'a, 'll, 'tcx> {
             })
             .collect();
 
-        return Cow::Owned(casted_args);
+        Cow::Owned(casted_args)
     }
 
     pub fn lifetime_start(&self, ptr: &'ll Value, size: Size) {

src/librustc_codegen_llvm/common.rs

@@ -336,16 +336,13 @@ pub fn langcall(tcx: TyCtxt,
                 msg: &str,
                 li: LangItem)
                 -> DefId {
-    match tcx.lang_items().require(li) {
+    tcx.lang_items().require(li).unwrap_or_else(|s| {
-        Ok(id) => id,
+        let msg = format!("{} {}", msg, s);
-        Err(s) => {
+        match span {
-            let msg = format!("{} {}", msg, s);
+            Some(span) => tcx.sess.span_fatal(span, &msg[..]),
-            match span {
+            None => tcx.sess.fatal(&msg[..]),
-                Some(span) => tcx.sess.span_fatal(span, &msg[..]),
-                None => tcx.sess.fatal(&msg[..]),
-            }
         }
-    }
+    })
 }
 
 // To avoid UB from LLVM, these two functions mask RHS with an

src/librustc_codegen_llvm/consts.rs

@@ -124,7 +124,7 @@ pub fn get_static(cx: &CodegenCx<'ll, '_>, def_id: DefId) -> &'ll Value {
     assert!(!defined_in_current_codegen_unit,
             "consts::get_static() should always hit the cache for \
              statics defined in the same CGU, but did not for `{:?}`",
-             def_id);
+            def_id);
 
     let ty = instance.ty(cx.tcx);
     let sym = cx.tcx.symbol_name(instance).as_str();
@@ -249,14 +249,13 @@ fn check_and_apply_linkage(
         // extern "C" fn() from being non-null, so we can't just declare a
         // static and call it a day. Some linkages (like weak) will make it such
         // that the static actually has a null value.
-        let llty2 = match ty.sty {
+        let llty2 = if let ty::RawPtr(ref mt) = ty.sty {
-            ty::RawPtr(ref mt) => cx.layout_of(mt.ty).llvm_type(cx),
+            cx.layout_of(mt.ty).llvm_type(cx)
-            _ => {
+        } else {
-                if span.is_some() {
+            if let Some(span) = span {
-                    cx.sess().span_fatal(span.unwrap(), "must have type `*const T` or `*mut T`")
+                cx.sess().span_fatal(span, "must have type `*const T` or `*mut T`")
-                } else {
+            } else {
-                    bug!("must have type `*const T` or `*mut T`")
+                bug!("must have type `*const T` or `*mut T`")
-                }
             }
         };
         unsafe {
@@ -273,9 +272,9 @@ fn check_and_apply_linkage(
             let mut real_name = "_rust_extern_with_linkage_".to_string();
             real_name.push_str(&sym);
             let g2 = declare::define_global(cx, &real_name, llty).unwrap_or_else(||{
-                if span.is_some() {
+                if let Some(span) = span {
                     cx.sess().span_fatal(
-                        span.unwrap(),
+                        span,
                         &format!("symbol `{}` is already defined", &sym)
                     )
                 } else {

src/librustc_codegen_llvm/context.rs

@@ -59,8 +59,8 @@ pub struct CodegenCx<'a, 'tcx: 'a> {
     /// Cache instances of monomorphic and polymorphic items
     pub instances: RefCell<FxHashMap<Instance<'tcx>, &'a Value>>,
     /// Cache generated vtables
-    pub vtables: RefCell<FxHashMap<(Ty<'tcx>,
+    pub vtables: RefCell<FxHashMap<(Ty<'tcx>, Option<ty::PolyExistentialTraitRef<'tcx>>),
-                                Option<ty::PolyExistentialTraitRef<'tcx>>), &'a Value>>,
+                                   &'a Value>>,
     /// Cache of constant strings,
     pub const_cstr_cache: RefCell<FxHashMap<LocalInternedString, &'a Value>>,
 
@@ -213,9 +213,9 @@ pub unsafe fn create_module(
 
 impl<'a, 'tcx> CodegenCx<'a, 'tcx> {
     crate fn new(tcx: TyCtxt<'a, 'tcx, 'tcx>,
-               codegen_unit: Arc<CodegenUnit<'tcx>>,
+                 codegen_unit: Arc<CodegenUnit<'tcx>>,
-               llvm_module: &'a ::ModuleLlvm)
+                 llvm_module: &'a ::ModuleLlvm)
-               -> CodegenCx<'a, 'tcx> {
+                 -> CodegenCx<'a, 'tcx> {
         // An interesting part of Windows which MSVC forces our hand on (and
         // apparently MinGW didn't) is the usage of `dllimport` and `dllexport`
         // attributes in LLVM IR as well as native dependencies (in C these
@@ -270,8 +270,8 @@ impl<'a, 'tcx> CodegenCx<'a, 'tcx> {
         let dbg_cx = if tcx.sess.opts.debuginfo != DebugInfo::None {
             let dctx = debuginfo::CrateDebugContext::new(llmod);
             debuginfo::metadata::compile_unit_metadata(tcx,
-                                                        &codegen_unit.name().as_str(),
+                                                       &codegen_unit.name().as_str(),
-                                                        &dctx);
+                                                       &dctx);
             Some(dctx)
         } else {
             None
@@ -318,10 +318,8 @@ impl<'b, 'tcx> CodegenCx<'b, 'tcx> {
         if let Some(v) = self.intrinsics.borrow().get(key).cloned() {
             return v;
         }
-        match declare_intrinsic(self, key) {
+
-            Some(v) => return v,
+        declare_intrinsic(self, key).unwrap_or_else(|| bug!("unknown intrinsic '{}'", key))
-            None => bug!("unknown intrinsic '{}'", key)
-        }
     }
 
     /// Generate a new symbol name with the given prefix. This symbol name must
@@ -465,9 +463,10 @@ impl LayoutOf for &'a CodegenCx<'ll, 'tcx> {
 
     fn layout_of(self, ty: Ty<'tcx>) -> Self::TyLayout {
         self.tcx.layout_of(ty::ParamEnv::reveal_all().and(ty))
-            .unwrap_or_else(|e| match e {
+            .unwrap_or_else(|e| if let LayoutError::SizeOverflow(_) = e {
-                LayoutError::SizeOverflow(_) => self.sess().fatal(&e.to_string()),
+                self.sess().fatal(&e.to_string())
-                _ => bug!("failed to get layout for `{}`: {}", ty, e)
+            } else {
+                bug!("failed to get layout for `{}`: {}", ty, e)
             })
     }
 }
@@ -772,5 +771,6 @@ fn declare_intrinsic(cx: &CodegenCx<'ll, '_>, key: &str) -> Option<&'ll Value> {
         ifn!("llvm.dbg.declare", fn(Type::metadata(cx), Type::metadata(cx)) -> void);
         ifn!("llvm.dbg.value", fn(Type::metadata(cx), t_i64, Type::metadata(cx)) -> void);
     }
-    return None;
+
+    None
 }

src/librustc_codegen_llvm/glue.rs

@@ -97,8 +97,8 @@ pub fn size_and_align_of_dst(bx: &Builder<'_, 'll, 'tcx>, t: Ty<'tcx>, info: Opt
                     C_usize(cx, std::cmp::max(sized_align, unsized_align) as u64)
                 }
                 _ => bx.select(bx.icmp(llvm::IntUGT, sized_align, unsized_align),
-                                sized_align,
+                               sized_align,
-                                unsized_align)
+                               unsized_align)
             };
 
             // Issue #27023: must add any necessary padding to `size`

src/librustc_codegen_llvm/intrinsic.rs

@@ -115,8 +115,8 @@ pub fn codegen_intrinsic_call(
     let llval = match name {
         _ if simple.is_some() => {
             bx.call(simple.unwrap(),
-                     &args.iter().map(|arg| arg.immediate()).collect::<Vec<_>>(),
+                    &args.iter().map(|arg| arg.immediate()).collect::<Vec<_>>(),
-                     None)
+                    None)
         }
         "unreachable" => {
             return;
@@ -373,7 +373,6 @@ pub fn codegen_intrinsic_call(
                     return;
                 }
             }
-
         },
         "fadd_fast" | "fsub_fast" | "fmul_fast" | "fdiv_fast" | "frem_fast" => {
             let sty = &arg_tys[0].sty;
@@ -540,10 +539,9 @@ pub fn codegen_intrinsic_call(
         }
 
         _ => {
-            let intr = match Intrinsic::find(&name) {
+            let intr = Intrinsic::find(&name).unwrap_or_else(||
-                Some(intr) => intr,
+                bug!("unknown intrinsic '{}'", name));
-                None => bug!("unknown intrinsic '{}'", name),
+
-            };
             fn one<T>(x: Vec<T>) -> T {
                 assert_eq!(x.len(), 1);
                 x.into_iter().next().unwrap()
@@ -822,8 +820,7 @@ fn codegen_msvc_try(
         let i64p = Type::i64(cx).ptr_to();
         let ptr_align = bx.tcx().data_layout.pointer_align;
         let slot = bx.alloca(i64p, "slot", ptr_align);
-        bx.invoke(func, &[data], normal.llbb(), catchswitch.llbb(),
+        bx.invoke(func, &[data], normal.llbb(), catchswitch.llbb(), None);
-            None);
 
         normal.ret(C_i32(cx, 0));
 
@@ -911,8 +908,7 @@ fn codegen_gnu_try(
         // being thrown.  The second value is a "selector" indicating which of
         // the landing pad clauses the exception's type had been matched to.
         // rust_try ignores the selector.
-        let lpad_ty = Type::struct_(cx, &[Type::i8p(cx), Type::i32(cx)],
+        let lpad_ty = Type::struct_(cx, &[Type::i8p(cx), Type::i32(cx)], false);
-                                    false);
         let vals = catch.landing_pad(lpad_ty, bx.cx.eh_personality(), 1);
         catch.add_clause(vals, C_null(Type::i8p(cx)));
         let ptr = catch.extract_value(vals, 0);
@@ -976,7 +972,7 @@ fn get_rust_try_fn<'ll, 'tcx>(
     let output = tcx.types.i32;
     let rust_try = gen_fn(cx, "__rust_try", vec![fn_ty, i8p, i8p], output, codegen);
     cx.rust_try_fn.set(Some(rust_try));
-    return rust_try
+    rust_try
 }
 
 fn span_invalid_monomorphization_error(a: &Session, b: Span, c: &str) {
@@ -1000,11 +996,11 @@ fn generic_simd_intrinsic(
         ($msg: tt, $($fmt: tt)*) => {
             span_invalid_monomorphization_error(
                 bx.sess(), span,
-                &format!(concat!("invalid monomorphization of `{}` intrinsic: ",
+                &format!(concat!("invalid monomorphization of `{}` intrinsic: ", $msg),
-                                 $msg),
                          name, $($fmt)*));
         }
     }
+
     macro_rules! return_error {
         ($($fmt: tt)*) => {
             {
@@ -1021,14 +1017,13 @@ fn generic_simd_intrinsic(
             }
         };
     }
+
     macro_rules! require_simd {
         ($ty: expr, $position: expr) => {
             require!($ty.is_simd(), "expected SIMD {} type, found non-SIMD `{}`", $position, $ty)
         }
     }
 
-
-
     let tcx = bx.tcx();
     let sig = tcx.normalize_erasing_late_bound_regions(
         ty::ParamEnv::reveal_all(),
@@ -1075,11 +1070,8 @@ fn generic_simd_intrinsic(
     }
 
     if name.starts_with("simd_shuffle") {
-        let n: usize = match name["simd_shuffle".len()..].parse() {
+        let n: usize = name["simd_shuffle".len()..].parse().unwrap_or_else(|_|
-            Ok(n) => n,
+            span_bug!(span, "bad `simd_shuffle` instruction only caught in codegen?"));
-            Err(_) => span_bug!(span,
-                                "bad `simd_shuffle` instruction only caught in codegen?")
-        };
 
         require_simd!(ret_ty, "return");
 
@@ -1121,8 +1113,8 @@ fn generic_simd_intrinsic(
         };
 
         return Ok(bx.shuffle_vector(args[0].immediate(),
-                                     args[1].immediate(),
+                                    args[1].immediate(),
-                                     C_vector(&indices)))
+                                    C_vector(&indices)))
     }
 
     if name == "simd_insert" {
@@ -1130,8 +1122,8 @@ fn generic_simd_intrinsic(
                  "expected inserted type `{}` (element of input `{}`), found `{}`",
                  in_elem, in_ty, arg_tys[2]);
         return Ok(bx.insert_element(args[0].immediate(),
-                                     args[2].immediate(),
+                                    args[2].immediate(),
-                                     args[1].immediate()))
+                                    args[1].immediate()))
     }
     if name == "simd_extract" {
         require!(ret_ty == in_elem,
@@ -1150,9 +1142,7 @@ fn generic_simd_intrinsic(
         );
         match m_elem_ty.sty {
             ty::Int(_) => {},
-            _ => {
+            _ => return_error!("mask element type is `{}`, expected `i_`", m_elem_ty)
-                return_error!("mask element type is `{}`, expected `i_`", m_elem_ty);
-            }
         }
         // truncate the mask to a vector of i1s
         let i1 = Type::i1(bx.cx);
@@ -1177,8 +1167,7 @@ fn generic_simd_intrinsic(
             ($msg: tt, $($fmt: tt)*) => {
                 span_invalid_monomorphization_error(
                     bx.sess(), span,
-                    &format!(concat!("invalid monomorphization of `{}` intrinsic: ",
+                    &format!(concat!("invalid monomorphization of `{}` intrinsic: ", $msg),
-                                     $msg),
                              name, $($fmt)*));
             }
         }
@@ -1223,63 +1212,53 @@ fn generic_simd_intrinsic(
                         &args.iter().map(|arg| arg.immediate()).collect::<Vec<_>>(),
                         None);
         unsafe { llvm::LLVMRustSetHasUnsafeAlgebra(c) };
-        return Ok(c);
+        Ok(c)
     }
 
-    if name == "simd_fsqrt" {
+    match name {
-        return simd_simple_float_intrinsic("sqrt", in_elem, in_ty, in_len, bx, span, args);
+        "simd_fsqrt" => {
-    }
+            return simd_simple_float_intrinsic("sqrt", in_elem, in_ty, in_len, bx, span, args);
-
+        }
-    if name == "simd_fsin" {
+        "simd_fsin" => {
-        return simd_simple_float_intrinsic("sin", in_elem, in_ty, in_len, bx, span, args);
+            return simd_simple_float_intrinsic("sin", in_elem, in_ty, in_len, bx, span, args);
-    }
+        }
-
+        "simd_fcos" => {
-    if name == "simd_fcos" {
+            return simd_simple_float_intrinsic("cos", in_elem, in_ty, in_len, bx, span, args);
-        return simd_simple_float_intrinsic("cos", in_elem, in_ty, in_len, bx, span, args);
+        }
-    }
+        "simd_fabs" => {
-
+            return simd_simple_float_intrinsic("fabs", in_elem, in_ty, in_len, bx, span, args);
-    if name == "simd_fabs" {
+        }
-        return simd_simple_float_intrinsic("fabs", in_elem, in_ty, in_len, bx, span, args);
+        "simd_floor" => {
-    }
+            return simd_simple_float_intrinsic("floor", in_elem, in_ty, in_len, bx, span, args);
-
+        }
-    if name == "simd_floor" {
+        "simd_ceil" => {
-        return simd_simple_float_intrinsic("floor", in_elem, in_ty, in_len, bx, span, args);
+            return simd_simple_float_intrinsic("ceil", in_elem, in_ty, in_len, bx, span, args);
-    }
+        }
-
+        "simd_fexp" => {
-    if name == "simd_ceil" {
+            return simd_simple_float_intrinsic("exp", in_elem, in_ty, in_len, bx, span, args);
-        return simd_simple_float_intrinsic("ceil", in_elem, in_ty, in_len, bx, span, args);
+        }
-    }
+        "simd_fexp2" => {
-
+            return simd_simple_float_intrinsic("exp2", in_elem, in_ty, in_len, bx, span, args);
-    if name == "simd_fexp" {
+        }
-        return simd_simple_float_intrinsic("exp", in_elem, in_ty, in_len, bx, span, args);
+        "simd_flog10" => {
-    }
+            return simd_simple_float_intrinsic("log10", in_elem, in_ty, in_len, bx, span, args);
-
+        }
-    if name == "simd_fexp2" {
+        "simd_flog2" => {
-        return simd_simple_float_intrinsic("exp2", in_elem, in_ty, in_len, bx, span, args);
+            return simd_simple_float_intrinsic("log2", in_elem, in_ty, in_len, bx, span, args);
-    }
+        }
-
+        "simd_flog" => {
-    if name == "simd_flog10" {
+            return simd_simple_float_intrinsic("log", in_elem, in_ty, in_len, bx, span, args);
-        return simd_simple_float_intrinsic("log10", in_elem, in_ty, in_len, bx, span, args);
+        }
-    }
+        "simd_fpowi" => {
-
+            return simd_simple_float_intrinsic("powi", in_elem, in_ty, in_len, bx, span, args);
-    if name == "simd_flog2" {
+        }
-        return simd_simple_float_intrinsic("log2", in_elem, in_ty, in_len, bx, span, args);
+        "simd_fpow" => {
-    }
+            return simd_simple_float_intrinsic("pow", in_elem, in_ty, in_len, bx, span, args);
-
+        }
-    if name == "simd_flog" {
+        "simd_fma" => {
-        return simd_simple_float_intrinsic("log", in_elem, in_ty, in_len, bx, span, args);
+            return simd_simple_float_intrinsic("fma", in_elem, in_ty, in_len, bx, span, args);
-    }
+        }
-
+        _ => { /* fallthrough */ }
-    if name == "simd_fpowi" {
-        return simd_simple_float_intrinsic("powi", in_elem, in_ty, in_len, bx, span, args);
-    }
-
-    if name == "simd_fpow"  {
-        return simd_simple_float_intrinsic("pow", in_elem, in_ty, in_len, bx, span, args);
-    }
-
-    if name == "simd_fma" {
-        return simd_simple_float_intrinsic("fma", in_elem, in_ty, in_len, bx, span, args);
     }
 
     // FIXME: use:
@@ -1312,7 +1291,7 @@ fn generic_simd_intrinsic(
     }
 
 
-    if name == "simd_gather"  {
+    if name == "simd_gather" {
         // simd_gather(values: <N x T>, pointers: <N x *_ T>,
         //             mask: <N x i{M}>) -> <N x T>
         // * N: number of elements in the input vectors
@@ -1360,7 +1339,7 @@ fn generic_simd_intrinsic(
         // to the element type of the first argument
         let (pointer_count, underlying_ty) = match arg_tys[1].simd_type(tcx).sty {
             ty::RawPtr(p) if p.ty == in_elem => (ptr_count(arg_tys[1].simd_type(tcx)),
-                                                   non_ptr(arg_tys[1].simd_type(tcx))),
+                                                 non_ptr(arg_tys[1].simd_type(tcx))),
             _ => {
                 require!(false, "expected element type `{}` of second argument `{}` \
                                  to be a pointer to the element type `{}` of the first \
@@ -1371,7 +1350,7 @@ fn generic_simd_intrinsic(
             }
         };
         assert!(pointer_count > 0);
-        assert!(pointer_count - 1 == ptr_count(arg_tys[0].simd_type(tcx)));
+        assert_eq!(pointer_count - 1, ptr_count(arg_tys[0].simd_type(tcx)));
         assert_eq!(underlying_ty, non_ptr(arg_tys[0].simd_type(tcx)));
 
         // The element type of the third argument must be a signed integer type of any width:
@@ -1414,7 +1393,7 @@ fn generic_simd_intrinsic(
         return Ok(v);
     }
 
-    if name == "simd_scatter"  {
+    if name == "simd_scatter" {
         // simd_scatter(values: <N x T>, pointers: <N x *mut T>,
         //             mask: <N x i{M}>) -> ()
         // * N: number of elements in the input vectors
@@ -1468,7 +1447,7 @@ fn generic_simd_intrinsic(
             }
         };
         assert!(pointer_count > 0);
-        assert!(pointer_count - 1 == ptr_count(arg_tys[0].simd_type(tcx)));
+        assert_eq!(pointer_count - 1, ptr_count(arg_tys[0].simd_type(tcx)));
         assert_eq!(underlying_ty, non_ptr(arg_tys[0].simd_type(tcx)));
 
         // The element type of the third argument must be a signed integer type of any width:
@@ -1570,7 +1549,6 @@ unsupported {} from `{}` with element `{}` of size `{}` to `{}`"#,
                                     )
                                 }
                             }
-
                         };
                         Ok(bx.$float_reduce(acc, args[0].immediate()))
                     }
@@ -1750,9 +1728,9 @@ unsupported {} from `{}` with element `{}` of size `{}` to `{}`"#,
                     _ => {},
                 }
                 require!(false,
-                            "unsupported operation on `{}` with element `{}`",
+                         "unsupported operation on `{}` with element `{}`",
-                            in_ty,
+                         in_ty,
-                            in_elem)
+                         in_elem)
             })*
         }
     }

src/librustc_codegen_llvm/lib.rs

@@ -306,7 +306,7 @@ impl ModuleCodegen {
         };
         let bytecode_compressed = if emit_bc_compressed {
             Some(outputs.temp_path(OutputType::Bitcode, Some(&self.name))
-                    .with_extension(RLIB_BYTECODE_EXTENSION))
+                        .with_extension(RLIB_BYTECODE_EXTENSION))
         } else {
             None
         };

src/librustc_codegen_llvm/llvm_util.rs

@@ -52,8 +52,9 @@ fn require_inited() {
 }
 
 unsafe fn configure_llvm(sess: &Session) {
-    let mut llvm_c_strs = Vec::new();
+    let n_args = sess.opts.cg.llvm_args.len();
-    let mut llvm_args = Vec::new();
+    let mut llvm_c_strs = Vec::with_capacity(n_args + 1);
+    let mut llvm_args = Vec::with_capacity(n_args + 1);
 
     {
         let mut add = |arg: &str| {

src/librustc_codegen_llvm/metadata.rs

@@ -63,7 +63,7 @@ impl MetadataLoader for LlvmMetadataLoader {
             let of = ObjectFile::new(mb)
                 .map(|of| OwningRef::new(box of))
                 .ok_or_else(|| format!("provided path not an object file: '{}'",
-                                        filename.display()))?;
+                                       filename.display()))?;
             let buf = of.try_map(|of| search_meta_section(of, target, filename))?;
             Ok(rustc_erase_owner!(buf))
         }

src/librustc_codegen_llvm/mir/analyze.rs

@@ -151,9 +151,9 @@ impl Visitor<'tcx> for LocalAnalyzer<'mir, 'a, 'll, 'tcx> {
     }
 
     fn visit_place(&mut self,
-                    place: &mir::Place<'tcx>,
+                   place: &mir::Place<'tcx>,
-                    context: PlaceContext<'tcx>,
+                   context: PlaceContext<'tcx>,
-                    location: Location) {
+                   location: Location) {
         debug!("visit_place(place={:?}, context={:?})", place, context);
         let cx = self.fx.cx;
 

src/librustc_codegen_llvm/mir/block.rs

@@ -49,9 +49,9 @@ impl FunctionCx<'a, 'll, 'tcx> {
     }
 
     fn codegen_terminator(&mut self,
-                        mut bx: Builder<'a, 'll, 'tcx>,
+                          mut bx: Builder<'a, 'll, 'tcx>,
-                        bb: mir::BasicBlock,
+                          bb: mir::BasicBlock,
-                        terminator: &mir::Terminator<'tcx>)
+                          terminator: &mir::Terminator<'tcx>)
     {
         debug!("codegen_terminator: {:?}", terminator);
 

src/librustc_codegen_llvm/mono_item.rs

@@ -108,8 +108,8 @@ pub trait MonoItemExt<'a, 'tcx>: fmt::Debug + BaseMonoItemExt<'a, 'tcx> {
         match *self.as_mono_item() {
             MonoItem::Fn(instance) => {
                 format!("Fn({:?}, {})",
-                         instance.def,
+                        instance.def,
-                         instance.substs.as_ptr() as usize)
+                        instance.substs.as_ptr() as usize)
             }
             MonoItem::Static(id) => {
                 format!("Static({:?})", id)

src/librustc_codegen_llvm/type_of.rs

@@ -65,13 +65,12 @@ fn uncached_llvm_type<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
             let mut name = String::with_capacity(32);
             let printer = DefPathBasedNames::new(cx.tcx, true, true);
             printer.push_type_name(layout.ty, &mut name);
-            match (&layout.ty.sty, &layout.variants) {
+            if let (&ty::Adt(def, _), &layout::Variants::Single { index })
-                (&ty::Adt(def, _), &layout::Variants::Single { index }) => {
+                 = (&layout.ty.sty, &layout.variants)
-                    if def.is_enum() && !def.variants.is_empty() {
+            {
-                        write!(&mut name, "::{}", def.variants[index].name).unwrap();
+                if def.is_enum() && !def.variants.is_empty() {
-                    }
+                    write!(&mut name, "::{}", def.variants[index].name).unwrap();
                 }
-                _ => {}
             }
             Some(name)
         }
@@ -132,7 +131,7 @@ fn struct_llfields<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
 
         debug!("struct_llfields: {}: {:?} offset: {:?} target_offset: {:?} \
                 effective_field_align: {}",
-            i, field, offset, target_offset, effective_field_align.abi());
+               i, field, offset, target_offset, effective_field_align.abi());
         assert!(target_offset >= offset);
         let padding = target_offset - offset;
         let padding_align = prev_effective_align.min(effective_field_align);
@@ -155,7 +154,7 @@ fn struct_llfields<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
         debug!("struct_llfields: pad_bytes: {:?} offset: {:?} stride: {:?}",
                padding, offset, layout.size);
         result.push(Type::padding_filler(cx, padding, padding_align));
-        assert!(result.len() == 1 + field_count * 2);
+        assert_eq!(result.len(), 1 + field_count * 2);
     } else {
         debug!("struct_llfields: offset: {:?} stride: {:?}",
                offset, layout.size);

src/librustc_codegen_llvm/value.rs

@@ -34,6 +34,6 @@ impl fmt::Debug for Value {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         f.write_str(&llvm::build_string(|s| unsafe {
             llvm::LLVMRustWriteValueToString(self, s);
-        }).expect("nun-UTF8 value description from LLVM"))
+        }).expect("non-UTF8 value description from LLVM"))
     }
 }