[all-commits] [llvm/llvm-project] f7de70: scudo: Simplify getClassIdBySize() logic. NFCI.

[pcc via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: f7de7084f4a2c346b3db87c26fa519db0781a09a
      https://github.com/llvm/llvm-project/commit/f7de7084f4a2c346b3db87c26fa519db0781a09a
  Author: Peter Collingbourne <peter at pcc.me.uk>
  Date:   2020-02-04 (Tue, 04 Feb 2020)

  Changed paths:
    M compiler-rt/lib/scudo/standalone/size_class_map.h

  Log Message:
  -----------
  scudo: Simplify getClassIdBySize() logic. NFCI.

By subtracting 1 from Size at the beginning we can simplify the
subsequent calculations. This also saves 4 instructions on aarch64
and 9 instructions on x86_64, but seems to be perf neutral.

Differential Revision: https://reviews.llvm.org/D73936