Speed up Python and NumPy compilation process

Uses `-j` flag on target/host python as well as numpy to run compilation
in parallel. In Python an optimum number of jobs is guessed if the flag
is used alone. In NumPy it must be explicitly set.

pythonforandroid/python.py

@@ -250,7 +250,7 @@ def build_arch(self, arch):
                 py_version = self.major_minor_version_string
                 if self.major_minor_version_string[0] == '3':
                     py_version += 'm'
-                shprint(sh.make, 'all',
+                shprint(sh.make, 'all', '-j',
                         'INSTSONAME=libpython{version}.so'.format(
                             version=py_version), _env=env)
 
@@ -420,7 +420,7 @@ def build_arch(self, arch):
                 shprint(sh.cp, join('Modules', 'Setup.dist'),
                         join(build_dir, 'Modules', 'Setup'))
 
-                result = shprint(sh.make, '-C', build_dir)
+                result = shprint(sh.make, '-j', '-C', build_dir)
         else:
             info('Skipping {name} ({version}) build, as it has already '
                  'been completed'.format(name=self.name, version=self.version))

pythonforandroid/recipes/numpy/__init__.py

@@ -1,4 +1,5 @@
 from pythonforandroid.recipe import CompiledComponentsPythonRecipe
+from multiprocessing import cpu_count
 from os.path import join
 
 
@@ -7,7 +8,6 @@ class NumpyRecipe(CompiledComponentsPythonRecipe):
     version = '1.15.1'
     url = 'https://pypi.python.org/packages/source/n/numpy/numpy-{version}.zip'
     site_packages_name = 'numpy'
-
     depends = [('python2', 'python3', 'python3crystax')]
 
     patches = [
@@ -18,6 +18,16 @@ class NumpyRecipe(CompiledComponentsPythonRecipe):
         join('patches', 'python-fixes.patch')
     ]
 
+    def build_compiled_components(self, arch):
+        setup_extra_args = ['-j', str(cpu_count())]
+        super(NumpyRecipe, self).build_compiled_components(arch)
+        setup_extra_args = []
+
+    def rebuild_compiled_components(self, arch, env):
+        setup_extra_args = ['-j', str(cpu_count())]
+        super(NumpyRecipe, self).rebuild_compiled_components(arch, env)
+        setup_extra_args = []
+
     def get_recipe_env(self, arch):
         env = super(NumpyRecipe, self).get_recipe_env(arch)
 
@@ -44,8 +54,5 @@ def get_recipe_env(self, arch):
             env['LD'] += flags + ' -shared'
         return env
 
-    def prebuild_arch(self, arch):
-        super(NumpyRecipe, self).prebuild_arch(arch)
-
 
 recipe = NumpyRecipe()