[Tarantool-patches] [PATCH v2 luajit 08/41] perf: adjust euler14-bit in LuaJIT-benches

[Sergey Kaplun via Tarantool-patches <tarantool-patches@dev.tarantool.org>]

This patch adjusts the aforementioned test to use the benchmark
framework introduced before. The default arguments are adjusted
according to the <PARAM_x86.txt> file. The arguments to the script still
can be provided in the command line run.
---
 perf/LuaJIT-benches/euler14-bit.lua | 65 ++++++++++++++++++++++-------
 1 file changed, 49 insertions(+), 16 deletions(-)

diff --git a/perf/LuaJIT-benches/euler14-bit.lua b/perf/LuaJIT-benches/euler14-bit.lua
index 537f2bf3..c4ae3713 100644
--- a/perf/LuaJIT-benches/euler14-bit.lua
+++ b/perf/LuaJIT-benches/euler14-bit.lua
@@ -1,22 +1,55 @@
+-- The benchmark to check the performance of bitwise operations.
+-- It finds the longest Collatz sequence using bitwise arithmetic.
+-- For the details see:
+-- https://projecteuler.net/problem=14
+
+local bench = require("bench").new(arg)
 
 local bit = require("bit")
 local bnot, bor, band = bit.bnot, bit.bor, bit.band
 local shl, shr = bit.lshift, bit.rshift
 
-local N = tonumber(arg and arg[1]) or 10000000
-local cache, m, n = { 1 }, 1, 1
-if arg and arg[2] then cache = nil end
-for i=2,N do
-  local j = i
-  for len=1,1000000000 do
-    j = bor(band(shr(j,1), band(j,1)-1), band(shl(j,1)+j+1, bnot(band(j,1)-1)))
-    if cache then
-      local x = cache[j]; if x then j = x+len; break end
-    elseif j == 1 then
-      j = len+1; break
+local DEFAULT_N = 2e7
+local N = tonumber(arg and arg[1]) or DEFAULT_N
+local drop_cache = arg and arg[2]
+
+bench:add({
+  name = "euler14_bit",
+  payload = function()
+    local cache, m, n = { 1 }, 1, 1
+    if drop_cache then cache = nil end
+    for i = 2, N do
+      local j = i
+      for len = 1, 1000000000 do
+        j = bor(
+          band(shr(j, 1), band(j, 1) - 1),
+          band(shl(j, 1) + j + 1, bnot(band(j, 1) - 1))
+        )
+        if cache then
+          local x = cache[j]
+          if x then
+            j = x + len
+            break
+          end
+        elseif j == 1 then
+          j = len + 1
+          break
+        end
+      end
+      if cache then cache[i] = j end
+      if j > m then m, n = j, i end
     end
-  end
-  if cache then cache[i] = j end
-  if j > m then m, n = j, i end
-end
-io.write("Found ", n, " (chain length: ", m, ")\n")
+    return {n = n, m = m}
+  end,
+  checker = function(res)
+    if N ~= DEFAULT_N then
+      -- Test only for the default.
+      return true
+    else
+      return res.n == 18064027 and res.m == 623
+    end
+  end,
+  items = N,
+})
+
+bench:run_and_report()
-- 
2.52.0