Author: Ronan Lamy <ronan.l...@gmail.com>
Branch: PyBuffer
Changeset: r90840:55b0a70b52e1
Date: 2017-03-28 14:14 +0100
http://bitbucket.org/pypy/pypy/changeset/55b0a70b52e1/
Log: Stop abusing SubBuffer to represent memoryview slices
diff --git a/pypy/objspace/std/memoryobject.py
b/pypy/objspace/std/memoryobject.py
--- a/pypy/objspace/std/memoryobject.py
+++ b/pypy/objspace/std/memoryobject.py
@@ -302,24 +302,14 @@
else:
raise oefmt(space.w_NotImplementedError, "multi-dimensional
sub-views are not implemented")
elif is_slice:
- mv = W_MemoryView.copy(self)
- mv.init_slice(start, stop, step, slicelength, 0)
- mv.init_len()
- mv._init_flags()
- return mv
+ return self.new_slice(start, stop, step, slicelength, 0)
# multi index is handled at the top of this function
else:
raise TypeError("memoryview: invalid slice key")
- def init_slice(self, start, stop, step, slicelength, dim):
- # modifies the buffer, shape and stride to allow step to be > 1
- self.strides = strides = self.getstrides()[:]
- self.shape = shape = self.getshape()[:]
- bytesize = self.getitemsize() * slicelength
- self.buf = SubBuffer(self.buf, strides[dim] * start, bytesize)
- shape[dim] = slicelength
- strides[dim] = strides[dim] * step
- # TODO subbuffer
+ def new_slice(self, start, stop, step, slicelength, dim):
+ sliced = BufferSlice(self.buf, start, step, slicelength)
+ return W_MemoryView(sliced, sliced.getformat(), sliced.getitemsize())
def init_len(self):
self.length = self.bytecount_from_shape()
@@ -678,7 +668,7 @@
def descr_hex(self, space):
from pypy.objspace.std.bytearrayobject import _array_to_hexstring
self._check_released(space)
- return _array_to_hexstring(space, self.buf, 0, 1, self.getlength())
+ return _array_to_hexstring(space, self.buf.as_binary(), 0, 1,
self.getlength())
def is_byte_format(char):
return char == 'b' or char == 'B' or char == 'c'
@@ -765,3 +755,65 @@
_IsFortranContiguous(ndim, shape, strides, itemsize))
return 0
+class BufferSlice(Buffer):
+ def __init__(self, buf, start, step, length):
+ self.buf = buf
+ self.readonly = self.buf.readonly
+ self.strides = buf.getstrides()[:]
+ itemsize = buf.getitemsize()
+ self.offset = start * itemsize
+ self.step = step
+ self.strides[0] *= step
+ self.shape = buf.getshape()[:]
+ self.shape[0] = length
+
+ def getlength(self):
+ return self.shape[0] * self.getitemsize()
+
+ def as_str(self):
+ return self.getslice(0, self.getlength(), 1, self.getlength())
+
+ def as_str_and_offset_maybe(self):
+ string, offset = self.buf.as_str_and_offset_maybe()
+ if string is not None:
+ return string, offset + self.offset
+ return None, 0
+
+ def getitem(self, index):
+ return self.buf.getitem(self.offset + index)
+
+ def setitem(self, index, char):
+ self.buf.setitem(self.offset + index, char)
+
+ def getslice(self, start, stop, step, size):
+ if start == stop:
+ return '' # otherwise, adding self.offset might make them
+ # out of bounds
+ return self.buf.getslice(self.offset + start, self.offset + stop,
+ step, size)
+
+ def setslice(self, start, string):
+ if len(string) == 0:
+ return # otherwise, adding self.offset might make 'start'
+ # out of bounds
+ self.buf.setslice(self.offset + start, string)
+
+ def get_raw_address(self):
+ from rpython.rtyper.lltypesystem import rffi
+ ptr = self.buf.get_raw_address()
+ return rffi.ptradd(ptr, self.offset)
+
+ def getformat(self):
+ return self.buf.getformat()
+
+ def getitemsize(self):
+ return self.buf.getitemsize()
+
+ def getndim(self):
+ return self.buf.getndim()
+
+ def getshape(self):
+ return self.shape
+
+ def getstrides(self):
+ return self.strides
_______________________________________________
pypy-commit mailing list
pypy-commit@python.org
https://mail.python.org/mailman/listinfo/pypy-commit
