diff options
Diffstat (limited to 'compiler/rustc_query_system')
| -rw-r--r-- | compiler/rustc_query_system/src/dep_graph/serialized.rs | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/compiler/rustc_query_system/src/dep_graph/serialized.rs b/compiler/rustc_query_system/src/dep_graph/serialized.rs index b5eda7b04a7..b01f65a5e45 100644 --- a/compiler/rustc_query_system/src/dep_graph/serialized.rs +++ b/compiler/rustc_query_system/src/dep_graph/serialized.rs @@ -12,7 +12,7 @@ //! node and edge count are stored at the end of the file, all the arrays can be //! pre-allocated with the right length. //! -//! The encoding of the de-pgraph is generally designed around the fact that fixed-size +//! The encoding of the dep-graph is generally designed around the fact that fixed-size //! reads of encoded data are generally faster than variable-sized reads. Ergo we adopt //! essentially the same varint encoding scheme used in the rmeta format; the edge lists //! for each node on the graph store a 2-bit integer which is the number of bytes per edge @@ -34,6 +34,10 @@ //! [`DepKind`], number of edges, and bytes per edge are all bit-packed together, if they fit. //! If the number of edges in this node does not fit in the bits available in the header, we //! store it directly after the header with leb128. +//! +//! Dep-graph indices are bulk allocated to threads inside `LocalEncoderState`. Having threads +//! own these indices helps avoid races when they are conditionally used when marking nodes green. +//! It also reduces congestion on the shared index count. use std::cell::RefCell; use std::cmp::max; |