From 4437c665b038fe29ddd468dc0efad924cd2e5726 Mon Sep 17 00:00:00 2001
From: Yuta Saito <kateinoigakukun@gmail.com>
Date: Mon, 27 Nov 2023 15:35:59 +0000
Subject: [PATCH] build: Parallelize `make` build by default

---
 lib/ruby_wasm/build.rb                   | 10 +++++++++-
 lib/ruby_wasm/build/product/baseruby.rb  |  5 ++++-
 lib/ruby_wasm/build/product/crossruby.rb |  1 +
 sig/ruby_wasm/build.rbs                  |  3 +++
 4 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/lib/ruby_wasm/build.rb b/lib/ruby_wasm/build.rb
index 5a29a622fe..01dfd748a9 100644
--- a/lib/ruby_wasm/build.rb
+++ b/lib/ruby_wasm/build.rb
@@ -5,9 +5,17 @@
 module RubyWasm
   # Build executor to run the actual build commands.
   class BuildExecutor
-    def initialize(verbose: false)
+    attr_reader :process_count
+
+    def initialize(verbose: false, process_count: nil)
       @verbose = verbose
       @github_actions_markup = ENV["ENABLE_GITHUB_ACTIONS_MARKUP"] != nil
+      __skip__ = begin
+        require "etc"
+        @process_count = process_count || Etc.nprocessors
+      rescue LoadError
+        @process_count = process_count || 1
+      end
     end
 
     def system(*args, chdir: nil, env: nil)
diff --git a/lib/ruby_wasm/build/product/baseruby.rb b/lib/ruby_wasm/build/product/baseruby.rb
index 9ba6bc51fa..065d86dbc7 100644
--- a/lib/ruby_wasm/build/product/baseruby.rb
+++ b/lib/ruby_wasm/build/product/baseruby.rb
@@ -28,7 +28,10 @@ def build(executor)
                       "--prefix=#{install_dir}",
                       "--disable-install-doc",
                       chdir: product_build_dir
-      executor.system "make", "install", chdir: product_build_dir
+      executor.system "make",
+                      "-j#{executor.process_count}",
+                      "install",
+                      chdir: product_build_dir
     end
   end
 end
diff --git a/lib/ruby_wasm/build/product/crossruby.rb b/lib/ruby_wasm/build/product/crossruby.rb
index 9bccbbf783..988c071372 100644
--- a/lib/ruby_wasm/build/product/crossruby.rb
+++ b/lib/ruby_wasm/build/product/crossruby.rb
@@ -33,6 +33,7 @@ def build(executor, crossruby)
       executor.mkdir_p objdir
       do_extconf executor, crossruby
       executor.system "make",
+                      "-j#{executor.process_count}",
                       "-C",
                       "#{objdir}",
                       *make_args(crossruby),
diff --git a/sig/ruby_wasm/build.rbs b/sig/ruby_wasm/build.rbs
index 396d533135..9a9838f672 100644
--- a/sig/ruby_wasm/build.rbs
+++ b/sig/ruby_wasm/build.rbs
@@ -224,8 +224,11 @@ module RubyWasm
   class BuildExecutor
     @verbose: bool
     @github_actions_markup: bool
+    @process_count: Integer
     @start_times: Hash[[Class, String], Time]
 
+    attr_reader process_count: Integer
+
     def initialize: (?verbose: bool) -> void
     def system: (*_ToS args, ?chdir: String?, ?env: Hash[String, String]?) -> void
     def rm_rf: (FileUtils::pathlist list) -> void