Re-export more rustc_span::symbol things from rustc_span.

`rustc_span::symbol` defines some things that are re-exported from
`rustc_span`, such as `Symbol` and `sym`. But it doesn't re-export some
closely related things such as `Ident` and `kw`. So you can do `use
rustc_span::{Symbol, sym}` but you have to do `use
rustc_span::symbol::{Ident, kw}`, which is inconsistent for no good
reason.

This commit re-exports `Ident`, `kw`, and `MacroRulesNormalizedIdent`,
and changes many `rustc_span::symbol::` qualifiers in `compiler/` to
`rustc_span::`. This is a 200+ net line of code reduction, mostly
because many files with two `use rustc_span` items can be reduced to
one.

compiler/rustc_codegen_ssa/src/assert_module_sources.rs

@@ -33,8 +33,7 @@ use rustc_hir::def_id::LOCAL_CRATE;
 use rustc_middle::mir::mono::CodegenUnitNameBuilder;
 use rustc_middle::ty::TyCtxt;
 use rustc_session::Session;
-use rustc_span::symbol::sym;
-use rustc_span::{Span, Symbol};
+use rustc_span::{Span, Symbol, sym};
 use thin_vec::ThinVec;
 use tracing::debug;
 

compiler/rustc_codegen_ssa/src/back/archive.rs

@@ -14,7 +14,7 @@ use object::read::macho::FatArch;
 use rustc_data_structures::fx::FxIndexSet;
 use rustc_data_structures::memmap::Mmap;
 use rustc_session::Session;
-use rustc_span::symbol::Symbol;
+use rustc_span::Symbol;
 use tempfile::Builder as TempFileBuilder;
 use tracing::trace;
 

compiler/rustc_codegen_ssa/src/back/link.rs

@@ -35,7 +35,7 @@ use rustc_session::utils::NativeLibKind;
 /// For all the linkers we support, and information they might
 /// need out of the shared crate context before we get rid of it.
 use rustc_session::{Session, filesearch};
-use rustc_span::symbol::Symbol;
+use rustc_span::Symbol;
 use rustc_target::spec::crt_objects::CrtObjects;
 use rustc_target::spec::{
     Cc, LinkOutputKind, LinkSelfContainedComponents, LinkSelfContainedDefault, LinkerFeatures,

compiler/rustc_codegen_ssa/src/back/linker.rs

@@ -16,7 +16,7 @@ use rustc_middle::middle::exported_symbols::{ExportedSymbol, SymbolExportInfo, S
 use rustc_middle::ty::TyCtxt;
 use rustc_session::Session;
 use rustc_session::config::{self, CrateType, DebugInfo, LinkerPluginLto, Lto, OptLevel, Strip};
-use rustc_span::symbol::sym;
+use rustc_span::sym;
 use rustc_target::spec::{Cc, LinkOutputKind, LinkerFlavor, Lld};
 use tracing::{debug, warn};
 

compiler/rustc_codegen_ssa/src/back/write.rs

@@ -33,8 +33,7 @@ use rustc_session::config::{
     self, CrateType, Lto, OutFileName, OutputFilenames, OutputType, Passes, SwitchWithOptPath,
 };
 use rustc_span::source_map::SourceMap;
-use rustc_span::symbol::sym;
-use rustc_span::{FileName, InnerSpan, Span, SpanData};
+use rustc_span::{FileName, InnerSpan, Span, SpanData, sym};
 use rustc_target::spec::{MergeFunctions, SanitizerSet};
 use tracing::debug;
 

compiler/rustc_codegen_ssa/src/base.rs

@@ -24,8 +24,7 @@ use rustc_middle::ty::layout::{HasTyCtxt, HasTypingEnv, LayoutOf, TyAndLayout};
 use rustc_middle::ty::{self, Instance, Ty, TyCtxt};
 use rustc_session::Session;
 use rustc_session::config::{self, CrateType, EntryFnType, OptLevel, OutputType};
-use rustc_span::symbol::sym;
-use rustc_span::{DUMMY_SP, Symbol};
+use rustc_span::{DUMMY_SP, Symbol, sym};
 use rustc_trait_selection::infer::at::ToTrace;
 use rustc_trait_selection::infer::{BoundRegionConversionTime, TyCtxtInferExt};
 use rustc_trait_selection::traits::{ObligationCause, ObligationCtxt};

compiler/rustc_codegen_ssa/src/codegen_attrs.rs

@@ -16,8 +16,7 @@ use rustc_middle::query::Providers;
 use rustc_middle::ty::{self as ty, TyCtxt};
 use rustc_session::parse::feature_err;
 use rustc_session::{Session, lint};
-use rustc_span::symbol::Ident;
-use rustc_span::{Span, sym};
+use rustc_span::{Ident, Span, sym};
 use rustc_target::spec::{SanitizerSet, abi};
 
 use crate::errors;

compiler/rustc_codegen_ssa/src/lib.rs

@@ -42,7 +42,7 @@ use rustc_session::Session;
 use rustc_session::config::{CrateType, OutputFilenames, OutputType, RUST_CGU_EXT};
 use rustc_session::cstore::{self, CrateSource};
 use rustc_session::utils::NativeLibKind;
-use rustc_span::symbol::Symbol;
+use rustc_span::Symbol;
 
 pub mod assert_module_sources;
 pub mod back;

compiler/rustc_codegen_ssa/src/mir/debuginfo.rs

@@ -10,8 +10,7 @@ use rustc_middle::ty::layout::{LayoutOf, TyAndLayout};
 use rustc_middle::ty::{Instance, Ty};
 use rustc_middle::{bug, mir, ty};
 use rustc_session::config::DebugInfo;
-use rustc_span::symbol::{Symbol, kw};
-use rustc_span::{BytePos, Span, hygiene};
+use rustc_span::{BytePos, Span, Symbol, hygiene, kw};
 
 use super::operand::{OperandRef, OperandValue};
 use super::place::{PlaceRef, PlaceValue};

compiler/rustc_codegen_ssa/src/target_features.rs

@@ -9,8 +9,7 @@ use rustc_middle::middle::codegen_fn_attrs::TargetFeature;
 use rustc_middle::query::Providers;
 use rustc_middle::ty::TyCtxt;
 use rustc_session::parse::feature_err;
-use rustc_span::Span;
-use rustc_span::symbol::{Symbol, sym};
+use rustc_span::{Span, Symbol, sym};
 use rustc_target::target_features;
 
 use crate::errors;

compiler/rustc_codegen_ssa/src/traits/backend.rs

@@ -11,7 +11,7 @@ use rustc_middle::ty::TyCtxt;
 use rustc_middle::util::Providers;
 use rustc_session::Session;
 use rustc_session::config::{self, OutputFilenames, PrintRequest};
-use rustc_span::symbol::Symbol;
+use rustc_span::Symbol;
 
 use super::CodegenObject;
 use super::write::WriteBackendMethods;