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| author | Charles Harris <charlesr.harris@gmail.com> | 2018-04-12 16:55:21 -0600 |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2018-04-12 16:55:21 -0600 |
| commit | 3ec88758813678aadedc58dbfd89646b05001a91 (patch) | |
| tree | 2368a01839d9d06fcd68da20d8e8033c4f9047cb /numpy/core/src | |
| parent | 265983b4ec859ad528623f3c5da7c96f83526f4f (diff) | |
| parent | 1f981eddb7108ac18a7eabfa5ad9cfaecd247b13 (diff) | |
| download | numpy-3ec88758813678aadedc58dbfd89646b05001a91.tar.gz | |
Merge pull request #10665 from pv/accumulate-same-nocopy
ENH: umath: don't make temporary copies for in-place accumulation
Diffstat (limited to 'numpy/core/src')
| -rw-r--r-- | numpy/core/src/umath/ufunc_object.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/numpy/core/src/umath/ufunc_object.c b/numpy/core/src/umath/ufunc_object.c index bf5a4ead3..6dd597b3a 100644 --- a/numpy/core/src/umath/ufunc_object.c +++ b/numpy/core/src/umath/ufunc_object.c @@ -3215,9 +3215,15 @@ PyUFunc_Accumulate(PyUFuncObject *ufunc, PyArrayObject *arr, PyArrayObject *out, */ ndim_iter = ndim; flags |= NPY_ITER_MULTI_INDEX; - /* Add some more flags */ - op_flags[0] |= NPY_ITER_UPDATEIFCOPY|NPY_ITER_ALIGNED; - op_flags[1] |= NPY_ITER_COPY|NPY_ITER_ALIGNED; + /* + * Add some more flags. + * + * The accumulation outer loop is 'elementwise' over the array, so turn + * on NPY_ITER_OVERLAP_ASSUME_ELEMENTWISE. That is, in-place + * accumulate(x, out=x) is safe to do without temporary copies. + */ + op_flags[0] |= NPY_ITER_UPDATEIFCOPY|NPY_ITER_ALIGNED|NPY_ITER_OVERLAP_ASSUME_ELEMENTWISE; + op_flags[1] |= NPY_ITER_COPY|NPY_ITER_ALIGNED|NPY_ITER_OVERLAP_ASSUME_ELEMENTWISE; op_dtypes_param = op_dtypes; op_dtypes[1] = op_dtypes[0]; NPY_UF_DBG_PRINT("Allocating outer iterator\n"); |