[all-commits] [llvm/llvm-project] 950141: Speedup some unicode rendering

[llvmbot via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 9501419e879e56273f504beda3b13bf6bf82ae2b
      https://github.com/llvm/llvm-project/commit/9501419e879e56273f504beda3b13bf6bf82ae2b
  Author: serge-sans-paille <sguelton at redhat.com>
  Date:   2020-12-03 (Thu, 03 Dec 2020)

  Changed paths:
    M llvm/lib/Support/Unicode.cpp
    M llvm/unittests/Support/UnicodeTest.cpp

  Log Message:
  -----------
  Speedup some unicode rendering

Use a fast path for column width computation for ascii characters. Especially
relevant for llvm-objdump.

before:

    % time ./bin/llvm-objdump -D  -j .text /lib/libc.so.6 >/dev/null
    ./bin/llvm-objdump -D -j .text /lib/libc.so.6 > /dev/null  0.75s user 0.01s system 99% cpu 0.757 total

after:

    % time ./bin/llvm-objdump -D  -j .text /lib/libc.so.6 >/dev/null
    ./bin/llvm-objdump -D -j .text /lib/libc.so.6 > /dev/null  0.37s user 0.01s system 99% cpu 0.378 total

Differential Revision: https://reviews.llvm.org/D92180