Optimize integer value dumps

[Watson1978]

To convert an Integer to a String, it needs to do division and remainder calculations many times. These calculations can consume more CPU cycles than other instructions.

This patch will prepare a lookup table which has the remainder (0~99) of a number divided by 100 and use the table to omit the calculation.

−	before	after	result
Oj.dump	3.816M	4.255M	1.115x

Environment

• Linux
  • Manjaro Linux x86_64
  • Kernel: 6.3.0-1-MANJARO
  • AMD Ryzen 7 5800H
  • gcc version 12.2.1
  • Ruby 3.2.2

Before

Warming up --------------------------------------
             Oj.dump   386.110k i/100ms
Calculating -------------------------------------
             Oj.dump      3.816M (± 1.4%) i/s -     19.306M in   5.060327s

After

Warming up --------------------------------------
             Oj.dump   425.525k i/100ms
Calculating -------------------------------------
             Oj.dump      4.255M (± 0.2%) i/s -     21.276M in   5.000424s

Test code

require 'bundler/inline'
gemfile do
  source 'https://rubygems.org'
  gem 'benchmark-ips'
  gem 'oj'
end

data = [646086033, 414841692, 706653378, 1069473884, 181209966, 515120040, 892957102, 689595306, 719771732, 651396679, 549722480]

Benchmark.ips do |x|
  x.report('Oj.dump') { Oj.dump(data) }
end

[ohler55]

Can you merge in your fix for truffle into this branch?

[Watson1978]

OK, rebased.

[ohler55]

Thank you

[Watson1978]

Can you merge this PR? :)

[ohler55]

Thank you for the reminder.