From 17a8aff20abdef46ae90801c85cc232e81443e1b Mon Sep 17 00:00:00 2001 From: Nicholas Nethercote Date: Thu, 28 Mar 2019 12:27:26 +1100 Subject: Use `SmallVec` in `TokenStreamBuilder`. This reduces by 12% the number of allocations done for a "clean incremental" of `webrender_api`, which reduces the instruction count by about 0.5%. It also reduces instruction counts by up to 1.4% across a range of rustc-perf benchmark runs. --- src/libsyntax/parse/attr.rs | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'src/libsyntax/parse') diff --git a/src/libsyntax/parse/attr.rs b/src/libsyntax/parse/attr.rs index 4211268f33e..e99a86e807f 100644 --- a/src/libsyntax/parse/attr.rs +++ b/src/libsyntax/parse/attr.rs @@ -6,6 +6,7 @@ use crate::parse::parser::{Parser, TokenType, PathStyle}; use crate::tokenstream::{TokenStream, TokenTree}; use log::debug; +use smallvec::smallvec; #[derive(Debug)] enum InnerAttributeParsePolicy<'a> { @@ -171,7 +172,7 @@ impl<'a> Parser<'a> { } else { self.parse_unsuffixed_lit()?.tokens() }; - TokenStream::from_streams(vec![eq.into(), tokens]) + TokenStream::from_streams(smallvec![eq.into(), tokens]) } else { TokenStream::empty() }; -- cgit 1.4.1-3-g733a5