From ff5660624d116b18603c04d7a4af5fe446b733d8 Mon Sep 17 00:00:00 2001 From: Dan Gohman Date: Mon, 2 Jul 2018 22:37:40 -0700 Subject: [PATCH] Clarify wording in a comment. --- lib/codegen/src/regalloc/liveness.rs | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/lib/codegen/src/regalloc/liveness.rs b/lib/codegen/src/regalloc/liveness.rs index 959e48183a..609b71c156 100644 --- a/lib/codegen/src/regalloc/liveness.rs +++ b/lib/codegen/src/regalloc/liveness.rs @@ -42,9 +42,9 @@ //! This algorithm has some disadvantages that makes us look elsewhere: //! //! - Quadratic memory use. We need a bit per variable per basic block in the function. -//! - Sparse representation. In practice, the majority of SSA values never leave their basic block, -//! and those that do span basic blocks rarely span a large number of basic blocks. This makes -//! the bit-vectors quite sparse. +//! - Dense representation of sparse data. In practice, the majority of SSA values never leave +//! their basic block, and those that do span basic blocks rarely span a large number of basic +//! blocks. This makes the data stored in the bitvectors quite sparse. //! - Traditionally, the data-flow equations were solved for real program *variables* which does //! not include temporaries used in evaluating expressions. We have an SSA form program which //! blurs the distinction between temporaries and variables. This makes the quadratic memory