ENH: intern some commonly used strings in the multiarray module

Allows improving dictionary lookup performance.

3 files changed, 51 insertions, 2 deletions

diff --git a/numpy/core/src/multiarray/ctors.c b/numpy/core/src/multiarray/ctors.c
index 3da2dfae7..c57df147a 100644
--- a/numpy/core/src/multiarray/ctors.c
+++ b/numpy/core/src/multiarray/ctors.c
@@ -12,6 +12,7 @@
 #include "npy_config.h"
 
 #include "npy_pycompat.h"
+#include "multiarraymodule.h"
 
 #include "common.h"
 #include "ctors.h"
@@ -1069,7 +1070,7 @@ PyArray_NewFromDescr_int(PyTypeObject *subtype, PyArray_Descr *descr, int nd,
     if ((subtype != &PyArray_Type)) {
         PyObject *res, *func, *args;
 
-        func = PyObject_GetAttrString((PyObject *)fa, "__array_finalize__");
+        func = PyObject_GetAttr((PyObject *)fa, npy_ma_str_array_finalize);
         if (func && func != Py_None) {
             if (NpyCapsule_Check(func)) {
                 /* A C-function is stored here */
@@ -3368,7 +3369,7 @@ PyArray_FromBuffer(PyObject *buf, PyArray_Descr *type,
 #endif
         ) {
         PyObject *newbuf;
-        newbuf = PyObject_GetAttrString(buf, "__buffer__");
+        newbuf = PyObject_GetAttr(buf, npy_ma_str_buffer);
         if (newbuf == NULL) {
             Py_DECREF(type);
             return NULL;
diff --git a/numpy/core/src/multiarray/multiarraymodule.c b/numpy/core/src/multiarray/multiarraymodule.c
index 7fade0832..463acbebd 100644
--- a/numpy/core/src/multiarray/multiarraymodule.c
+++ b/numpy/core/src/multiarray/multiarraymodule.c
@@ -56,6 +56,7 @@ NPY_NO_EXPORT int NPY_NUMUSERTYPES = 0;
 #include "common.h"
 #include "ufunc_override.h"
 #include "scalarmathmodule.h" /* for npy_mul_with_overflow_intp */
+#include "multiarraymodule.h"
 
 /* Only here for API compatibility */
 NPY_NO_EXPORT PyTypeObject PyBigArray_Type;
@@ -4022,6 +4023,38 @@ set_flaginfo(PyObject *d)
     return;
 }
 
+NPY_VISIBILITY_HIDDEN PyObject * npy_ma_str_array = NULL;
+NPY_VISIBILITY_HIDDEN PyObject * npy_ma_str_array_prepare = NULL;
+NPY_VISIBILITY_HIDDEN PyObject * npy_ma_str_array_wrap = NULL;
+NPY_VISIBILITY_HIDDEN PyObject * npy_ma_str_array_finalize = NULL;
+NPY_VISIBILITY_HIDDEN PyObject * npy_ma_str_buffer = NULL;
+NPY_VISIBILITY_HIDDEN PyObject * npy_ma_str_ufunc = NULL;
+NPY_VISIBILITY_HIDDEN PyObject * npy_ma_str_order = NULL;
+NPY_VISIBILITY_HIDDEN PyObject * npy_ma_str_copy = NULL;
+NPY_VISIBILITY_HIDDEN PyObject * npy_ma_str_dtype = NULL;
+NPY_VISIBILITY_HIDDEN PyObject * npy_ma_str_ndmin = NULL;
+
+static int
+intern_strings(void)
+{
+    npy_ma_str_array = PyUString_InternFromString("__array__");
+    npy_ma_str_array_prepare = PyUString_InternFromString("__array_prepare__");
+    npy_ma_str_array_wrap = PyUString_InternFromString("__array_wrap__");
+    npy_ma_str_array_finalize = PyUString_InternFromString("__array_finalize__");
+    npy_ma_str_buffer = PyUString_InternFromString("__buffer__");
+    npy_ma_str_ufunc = PyUString_InternFromString("__numpy_ufunc__");
+    npy_ma_str_order = PyUString_InternFromString("order");
+    npy_ma_str_copy = PyUString_InternFromString("copy");
+    npy_ma_str_dtype = PyUString_InternFromString("dtype");
+    npy_ma_str_ndmin = PyUString_InternFromString("ndmin");
+
+    return npy_ma_str_array && npy_ma_str_array_prepare &&
+           npy_ma_str_array_wrap && npy_ma_str_array_finalize &&
+           npy_ma_str_array_finalize && npy_ma_str_ufunc &&
+           npy_ma_str_order && npy_ma_str_copy && npy_ma_str_dtype &&
+           npy_ma_str_ndmin;
+}
+
 #if defined(NPY_PY3K)
 static struct PyModuleDef moduledef = {
         PyModuleDef_HEAD_INIT,
@@ -4194,6 +4227,10 @@ PyMODINIT_FUNC initmultiarray(void) {
 
     set_flaginfo(d);
 
+    if (!intern_strings()) {
+        goto err;
+    }
+
     if (set_typeinfo(d) != 0) {
         goto err;
     }
diff --git a/numpy/core/src/multiarray/multiarraymodule.h b/numpy/core/src/multiarray/multiarraymodule.h
index 5a3b14b0b..82ae24845 100644
--- a/numpy/core/src/multiarray/multiarraymodule.h
+++ b/numpy/core/src/multiarray/multiarraymodule.h
@@ -1,4 +1,15 @@
 #ifndef _NPY_MULTIARRAY_H_
 #define _NPY_MULTIARRAY_H_
 
+NPY_VISIBILITY_HIDDEN extern PyObject * npy_ma_str_array;
+NPY_VISIBILITY_HIDDEN extern PyObject * npy_ma_str_array_prepare;
+NPY_VISIBILITY_HIDDEN extern PyObject * npy_ma_str_array_wrap;
+NPY_VISIBILITY_HIDDEN extern PyObject * npy_ma_str_array_finalize;
+NPY_VISIBILITY_HIDDEN extern PyObject * npy_ma_str_buffer;
+NPY_VISIBILITY_HIDDEN extern PyObject * npy_ma_str_ufunc;
+NPY_VISIBILITY_HIDDEN extern PyObject * npy_ma_str_order;
+NPY_VISIBILITY_HIDDEN extern PyObject * npy_ma_str_copy;
+NPY_VISIBILITY_HIDDEN extern PyObject * npy_ma_str_dtype;
+NPY_VISIBILITY_HIDDEN extern PyObject * npy_ma_str_ndmin;
+
 #endif