Undo the const_str changes from the previous commit.

src/librustc_codegen_llvm/common.rs

@@ -15,7 +15,7 @@ use rustc_codegen_ssa::traits::*;
 use rustc_middle::bug;
 use rustc_middle::mir::interpret::{Allocation, GlobalAlloc, Scalar};
 use rustc_middle::ty::layout::TyAndLayout;
-use rustc_middle::ty::SymbolName;
+use rustc_span::symbol::Symbol;
 use rustc_target::abi::{self, HasDataLayout, LayoutOf, Pointer, Size};
 
 use libc::{c_char, c_uint};
@@ -105,16 +105,17 @@ impl CodegenCx<'ll, 'tcx> {
         bytes_in_context(self.llcx, bytes)
     }
 
-    fn const_cstr(&self, s: SymbolName<'tcx>, null_terminated: bool) -> &'ll Value {
+    fn const_cstr(&self, s: Symbol, null_terminated: bool) -> &'ll Value {
         unsafe {
             if let Some(&llval) = self.const_cstr_cache.borrow().get(&s) {
                 return llval;
             }
 
+            let s_str = s.as_str();
             let sc = llvm::LLVMConstStringInContext(
                 self.llcx,
-                s.name.as_ptr() as *const c_char,
-                s.name.len() as c_uint,
+                s_str.as_ptr() as *const c_char,
+                s_str.len() as c_uint,
                 !null_terminated as Bool,
             );
             let sym = self.generate_local_symbol_name("str");
@@ -201,8 +202,8 @@ impl ConstMethods<'tcx> for CodegenCx<'ll, 'tcx> {
         unsafe { llvm::LLVMConstReal(t, val) }
     }
 
-    fn const_str(&self, s: SymbolName<'tcx>) -> (&'ll Value, &'ll Value) {
-        let len = s.name.len();
+    fn const_str(&self, s: Symbol) -> (&'ll Value, &'ll Value) {
+        let len = s.as_str().len();
         let cs = consts::ptrcast(
             self.const_cstr(s, false),
             self.type_ptr_to(self.layout_of(self.tcx.types.str_).llvm_type(self)),

src/librustc_codegen_llvm/context.rs

@@ -16,10 +16,11 @@ use rustc_data_structures::small_c_str::SmallCStr;
 use rustc_middle::bug;
 use rustc_middle::mir::mono::CodegenUnit;
 use rustc_middle::ty::layout::{HasParamEnv, LayoutError, TyAndLayout};
-use rustc_middle::ty::{self, Instance, SymbolName, Ty, TyCtxt};
+use rustc_middle::ty::{self, Instance, Ty, TyCtxt};
 use rustc_session::config::{CFGuard, CrateType, DebugInfo};
 use rustc_session::Session;
 use rustc_span::source_map::{Span, DUMMY_SP};
+use rustc_span::symbol::Symbol;
 use rustc_target::abi::{HasDataLayout, LayoutOf, PointeeInfo, Size, TargetDataLayout, VariantIdx};
 use rustc_target::spec::{HasTargetSpec, RelocModel, Target, TlsModel};
 
@@ -46,7 +47,7 @@ pub struct CodegenCx<'ll, 'tcx> {
     pub vtables:
         RefCell<FxHashMap<(Ty<'tcx>, Option<ty::PolyExistentialTraitRef<'tcx>>), &'ll Value>>,
     /// Cache of constant strings,
-    pub const_cstr_cache: RefCell<FxHashMap<SymbolName<'tcx>, &'ll Value>>,
+    pub const_cstr_cache: RefCell<FxHashMap<Symbol, &'ll Value>>,
 
     /// Reverse-direction for const ptrs cast from globals.
     ///

src/librustc_codegen_llvm/intrinsic.rs

@@ -196,7 +196,7 @@ impl IntrinsicCallMethods<'tcx> for Builder<'a, 'll, 'tcx> {
                 // and/or monomorphization invalidates these assumptions.
                 let coverageinfo = tcx.coverageinfo(caller_instance.def_id());
                 let mangled_fn = tcx.symbol_name(caller_instance);
-                let (mangled_fn_name, _len_val) = self.const_str(mangled_fn);
+                let (mangled_fn_name, _len_val) = self.const_str(Symbol::intern(mangled_fn.name));
                 let hash = self.const_u64(coverageinfo.hash);
                 let num_counters = self.const_u32(coverageinfo.num_counters);
                 use coverage::count_code_region_args::*;

src/librustc_codegen_ssa/mir/block.rs

@@ -16,7 +16,7 @@ use rustc_middle::mir;
 use rustc_middle::mir::interpret::{AllocId, ConstValue, Pointer, Scalar};
 use rustc_middle::mir::AssertKind;
 use rustc_middle::ty::layout::{FnAbiExt, HasTyCtxt};
-use rustc_middle::ty::{self, Instance, SymbolName, Ty, TypeFoldable};
+use rustc_middle::ty::{self, Instance, Ty, TypeFoldable};
 use rustc_span::source_map::Span;
 use rustc_span::{sym, Symbol};
 use rustc_target::abi::call::{ArgAbi, FnAbi, PassMode};
@@ -423,7 +423,8 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                 (lang_items::PanicBoundsCheckFnLangItem, vec![index, len, location])
             }
             _ => {
-                let msg = bx.const_str(SymbolName::new(bx.tcx(), msg.description()));
+                let msg_str = Symbol::intern(msg.description());
+                let msg = bx.const_str(msg_str);
                 // It's `pub fn panic(expr: &str)`, with the wide reference being passed
                 // as two arguments, and `#[track_caller]` adds an implicit third argument.
                 (lang_items::PanicFnLangItem, vec![msg.0, msg.1, location])
@@ -486,7 +487,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                 } else {
                     format!("attempted to leave type `{}` uninitialized, which is invalid", ty)
                 };
-                let msg = bx.const_str(SymbolName::new(bx.tcx(), &msg_str));
+                let msg = bx.const_str(Symbol::intern(&msg_str));
                 let location = self.get_caller_location(bx, span).immediate();
 
                 // Obtain the panic entry point.

src/librustc_codegen_ssa/traits/consts.rs

@@ -2,7 +2,7 @@ use super::BackendTypes;
 use crate::mir::place::PlaceRef;
 use rustc_middle::mir::interpret::{Allocation, Scalar};
 use rustc_middle::ty::layout::TyAndLayout;
-use rustc_middle::ty::SymbolName;
+use rustc_span::Symbol;
 use rustc_target::abi::{self, Size};
 
 pub trait ConstMethods<'tcx>: BackendTypes {
@@ -20,7 +20,7 @@ pub trait ConstMethods<'tcx>: BackendTypes {
     fn const_u8(&self, i: u8) -> Self::Value;
     fn const_real(&self, t: Self::Type, val: f64) -> Self::Value;
 
-    fn const_str(&self, s: SymbolName<'tcx>) -> (Self::Value, Self::Value);
+    fn const_str(&self, s: Symbol) -> (Self::Value, Self::Value);
     fn const_struct(&self, elts: &[Self::Value], packed: bool) -> Self::Value;
 
     fn const_to_opt_uint(&self, v: Self::Value) -> Option<u64>;