[all-commits] [llvm/llvm-project] 89950a: [DebugInfo][InstrRef] Track a single variable at a...

[Jeremy Morse via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 89950ade216bcabf3cb9acf2cf7218763fd40a92
      https://github.com/llvm/llvm-project/commit/89950ade216bcabf3cb9acf2cf7218763fd40a92
  Author: Jeremy Morse <jeremy.morse at sony.com>
  Date:   2021-10-20 (Wed, 20 Oct 2021)

  Changed paths:
    M llvm/lib/CodeGen/LiveDebugValues/InstrRefBasedImpl.cpp
    M llvm/lib/CodeGen/LiveDebugValues/InstrRefBasedImpl.h
    M llvm/unittests/CodeGen/InstrRefLDVTest.cpp

  Log Message:
  -----------
  [DebugInfo][InstrRef] Track a single variable at a time

Here's another performance patch for InstrRefBasedLDV: rather than
processing all variable values in a scope at a time, instead, process one
variable at a time. The benefits are twofold:
 * It's easier to reason about one variable at a time in your mind,
 * It improves performance, apparently from increased locality.

The downside is that the value-propagation code gets indented one level
further, plus there's some churn in the unit tests.

Differential Revision: https://reviews.llvm.org/D111799