2 files changed, 44 insertions, 33 deletions

diff --git a/compiler/rustc_ast/src/util/literal.rs b/compiler/rustc_ast/src/util/literal.rs
index a0a925d4700..4cc4b6367b4 100644
--- a/compiler/rustc_ast/src/util/literal.rs
+++ b/compiler/rustc_ast/src/util/literal.rs
@@ -8,6 +8,26 @@ use rustc_span::Span;
 use std::ascii;
 use std::str;
 
+// Escapes a string, represented as a symbol. Reuses the original symbol,
+// avoiding interning, if no changes are required.
+pub fn escape_string_symbol(symbol: Symbol) -> Symbol {
+    let s = symbol.as_str();
+    let escaped = s.escape_default().to_string();
+    if s == escaped { symbol } else { Symbol::intern(&escaped) }
+}
+
+// Escapes a char.
+pub fn escape_char_symbol(ch: char) -> Symbol {
+    let s: String = ch.escape_default().map(Into::<char>::into).collect();
+    Symbol::intern(&s)
+}
+
+// Escapes a byte string.
+pub fn escape_byte_str_symbol(bytes: &[u8]) -> Symbol {
+    let s = bytes.escape_ascii().to_string();
+    Symbol::intern(&s)
+}
+
 #[derive(Debug)]
 pub enum LitError {
     LexerError,
@@ -149,16 +169,11 @@ impl LitKind {
     pub fn synthesize_token_lit(&self) -> token::Lit {
         let (kind, symbol, suffix) = match *self {
             LitKind::Str(symbol, ast::StrStyle::Cooked) => {
-                // Don't re-intern unless the escaped string is different.
-                let s = symbol.as_str();
-                let escaped = s.escape_default().to_string();
-                let symbol = if s == escaped { symbol } else { Symbol::intern(&escaped) };
-                (token::Str, symbol, None)
+                (token::Str, escape_string_symbol(symbol), None)
             }
             LitKind::Str(symbol, ast::StrStyle::Raw(n)) => (token::StrRaw(n), symbol, None),
             LitKind::ByteStr(ref bytes, ast::StrStyle::Cooked) => {
-                let string = bytes.escape_ascii().to_string();
-                (token::ByteStr, Symbol::intern(&string), None)
+                (token::ByteStr, escape_byte_str_symbol(bytes), None)
             }
             LitKind::ByteStr(ref bytes, ast::StrStyle::Raw(n)) => {
                 // Unwrap because raw byte string literals can only contain ASCII.
@@ -169,10 +184,7 @@ impl LitKind {
                 let string: String = ascii::escape_default(byte).map(Into::<char>::into).collect();
                 (token::Byte, Symbol::intern(&string), None)
             }
-            LitKind::Char(ch) => {
-                let string: String = ch.escape_default().map(Into::<char>::into).collect();
-                (token::Char, Symbol::intern(&string), None)
-            }
+            LitKind::Char(ch) => (token::Char, escape_char_symbol(ch), None),
             LitKind::Int(n, ty) => {
                 let suffix = match ty {
                     ast::LitIntType::Unsigned(ty) => Some(ty.name()),
diff --git a/compiler/rustc_expand/src/build.rs b/compiler/rustc_expand/src/build.rs
index d8245ff613a..2fec24a1aec 100644
--- a/compiler/rustc_expand/src/build.rs
+++ b/compiler/rustc_expand/src/build.rs
@@ -1,8 +1,7 @@
 use crate::base::ExtCtxt;
-use rustc_ast::attr;
 use rustc_ast::ptr::P;
 use rustc_ast::{self as ast, AttrVec, BlockCheckMode, Expr, LocalKind, PatKind, UnOp};
-use rustc_data_structures::sync::Lrc;
+use rustc_ast::{attr, token, util::literal};
 use rustc_span::source_map::Spanned;
 use rustc_span::symbol::{kw, sym, Ident, Symbol};
 use rustc_span::Span;
@@ -332,36 +331,36 @@ impl<'a> ExtCtxt<'a> {
         self.expr_struct(span, self.path_ident(span, id), fields)
     }
 
-    fn expr_lit(&self, span: Span, lit_kind: ast::LitKind) -> P<ast::Expr> {
-        let token_lit = lit_kind.synthesize_token_lit();
-        self.expr(span, ast::ExprKind::Lit(token_lit))
+    pub fn expr_usize(&self, span: Span, n: usize) -> P<ast::Expr> {
+        let suffix = Some(ast::UintTy::Usize.name());
+        let lit = token::Lit::new(token::Integer, sym::integer(n), suffix);
+        self.expr(span, ast::ExprKind::Lit(lit))
     }
 
-    pub fn expr_usize(&self, span: Span, i: usize) -> P<ast::Expr> {
-        self.expr_lit(
-            span,
-            ast::LitKind::Int(i as u128, ast::LitIntType::Unsigned(ast::UintTy::Usize)),
-        )
-    }
-
-    pub fn expr_u32(&self, sp: Span, u: u32) -> P<ast::Expr> {
-        self.expr_lit(sp, ast::LitKind::Int(u as u128, ast::LitIntType::Unsigned(ast::UintTy::U32)))
+    pub fn expr_u32(&self, span: Span, n: u32) -> P<ast::Expr> {
+        let suffix = Some(ast::UintTy::U32.name());
+        let lit = token::Lit::new(token::Integer, sym::integer(n), suffix);
+        self.expr(span, ast::ExprKind::Lit(lit))
     }
 
-    pub fn expr_bool(&self, sp: Span, value: bool) -> P<ast::Expr> {
-        self.expr_lit(sp, ast::LitKind::Bool(value))
+    pub fn expr_bool(&self, span: Span, value: bool) -> P<ast::Expr> {
+        let lit = token::Lit::new(token::Bool, if value { kw::True } else { kw::False }, None);
+        self.expr(span, ast::ExprKind::Lit(lit))
     }
 
-    pub fn expr_str(&self, sp: Span, s: Symbol) -> P<ast::Expr> {
-        self.expr_lit(sp, ast::LitKind::Str(s, ast::StrStyle::Cooked))
+    pub fn expr_str(&self, span: Span, s: Symbol) -> P<ast::Expr> {
+        let lit = token::Lit::new(token::Str, literal::escape_string_symbol(s), None);
+        self.expr(span, ast::ExprKind::Lit(lit))
     }
 
-    pub fn expr_char(&self, sp: Span, ch: char) -> P<ast::Expr> {
-        self.expr_lit(sp, ast::LitKind::Char(ch))
+    pub fn expr_char(&self, span: Span, ch: char) -> P<ast::Expr> {
+        let lit = token::Lit::new(token::Char, literal::escape_char_symbol(ch), None);
+        self.expr(span, ast::ExprKind::Lit(lit))
     }
 
-    pub fn expr_byte_str(&self, sp: Span, bytes: Vec<u8>) -> P<ast::Expr> {
-        self.expr_lit(sp, ast::LitKind::ByteStr(Lrc::from(bytes), ast::StrStyle::Cooked))
+    pub fn expr_byte_str(&self, span: Span, bytes: Vec<u8>) -> P<ast::Expr> {
+        let lit = token::Lit::new(token::ByteStr, literal::escape_byte_str_symbol(&bytes), None);
+        self.expr(span, ast::ExprKind::Lit(lit))
     }
 
     /// `[expr1, expr2, ...]`