ENH: add new function `_opt_info()` to utils provides the optimization info of NumPy build

3 files changed, 38 insertions, 24 deletions

diff --git a/benchmarks/benchmarks/__init__.py b/benchmarks/benchmarks/__init__.py
index 50dd0898c..7b9f1d3e6 100644
--- a/benchmarks/benchmarks/__init__.py
+++ b/benchmarks/benchmarks/__init__.py
@@ -47,7 +47,7 @@ def dirty_lock(lock_name, lock_on_count=1):
         pass
     return False
 
+
 # FIXME: there's no official way to provide extra information to the test log
 if not dirty_lock("print_cpu_features.lock"):
     show_cpu_features()
-
diff --git a/numpy/_pytesttester.py b/numpy/_pytesttester.py
index 813e069a4..acfaa1ca5 100644
--- a/numpy/_pytesttester.py
+++ b/numpy/_pytesttester.py
@@ -35,25 +35,13 @@ __all__ = ['PytestTester']
 
 
 def _show_numpy_info():
-    from numpy.core._multiarray_umath import (
-        __cpu_features__, __cpu_baseline__, __cpu_dispatch__
-    )
     import numpy as np
 
     print("NumPy version %s" % np.__version__)
     relaxed_strides = np.ones((10, 1), order="C").flags.f_contiguous
     print("NumPy relaxed strides checking option:", relaxed_strides)
-
-    if len(__cpu_baseline__) == 0 and len(__cpu_dispatch__) == 0:
-        enabled_features = "nothing enabled"
-    else:
-        enabled_features = ' '.join(__cpu_baseline__)
-        for feature in __cpu_dispatch__:
-            if __cpu_features__[feature]:
-                enabled_features += " %s*" % feature
-            else:
-                enabled_features += " %s?" % feature
-    print("NumPy CPU features:", enabled_features)
+    info = np.lib.utils._opt_info()
+    print("NumPy CPU features: ", (info if info else 'nothing enabled'))
 
 
 
diff --git a/numpy/lib/utils.py b/numpy/lib/utils.py
index 91e7cb8a3..12a7cacdc 100644
--- a/numpy/lib/utils.py
+++ b/numpy/lib/utils.py
@@ -197,20 +197,20 @@ def deprecate(*args, **kwargs):
 def deprecate_with_doc(msg):
     """
     Deprecates a function and includes the deprecation in its docstring.
-    
-    This function is used as a decorator. It returns an object that can be 
-    used to issue a DeprecationWarning, by passing the to-be decorated 
-    function as argument, this adds warning to the to-be decorated function's 
+
+    This function is used as a decorator. It returns an object that can be
+    used to issue a DeprecationWarning, by passing the to-be decorated
+    function as argument, this adds warning to the to-be decorated function's
     docstring and returns the new function object.
-    
+
     See Also
     --------
-    deprecate : Decorate a function such that it issues a `DeprecationWarning` 
-    
+    deprecate : Decorate a function such that it issues a `DeprecationWarning`
+
     Parameters
     ----------
     msg : str
-        Additional explanation of the deprecation. Displayed in the 
+        Additional explanation of the deprecation. Displayed in the
         docstring after the warning.
 
     Returns
@@ -218,7 +218,7 @@ def deprecate_with_doc(msg):
     obj : object
 
     """
-    return _Deprecate(message=msg)  
+    return _Deprecate(message=msg)
 
 
 #--------------------------------------------
@@ -1042,4 +1042,30 @@ def _median_nancheck(data, result, axis, out):
         result[n] = np.nan
     return result
 
+def _opt_info():
+    """
+    Returns a string contains the supported CPU features by the current build.
+
+    The string format can be explained as follows:
+        - dispatched features that are supported by the running machine
+          end with `*`.
+        - dispatched features that are "not" supported by the running machine
+          end with `?`.
+        - remained features are representing the baseline.
+    """
+    from numpy.core._multiarray_umath import (
+        __cpu_features__, __cpu_baseline__, __cpu_dispatch__
+    )
+
+    if len(__cpu_baseline__) == 0 and len(__cpu_dispatch__) == 0:
+        return ''
+
+    enabled_features = ' '.join(__cpu_baseline__)
+    for feature in __cpu_dispatch__:
+        if __cpu_features__[feature]:
+            enabled_features += f" {feature}*"
+        else:
+            enabled_features += f" {feature}?"
+
+    return enabled_features
 #-----------------------------------------------------------------------------