def _find_linear_terms(rhs_exprs, u):
"""Help function that takes a list of rhs expressions and return a
list of bools determining what component, rhs_exprs[i], is linear
wrt u[i].
"""
uu = [Constant(1.0) for _ in rhs_exprs]
if len(rhs_exprs) > 1:
repl = {u: ufl.as_vector(uu)}
else:
repl = {u: uu[0]}
linear_terms = []
for i, ui in enumerate(uu):
comp_i_s = expand_indices(ufl.replace(rhs_exprs[i], repl))
linear_terms.append(ui in extract_coefficients(comp_i_s) and
ui not in extract_coefficients(
expand_derivatives(ufl.diff(comp_i_s, ui))))
return linear_terms
def derivative(form, u, du=None, coefficient_derivatives=None):
"""Compute the derivative of a form.
Given a form, this computes its linearization with respect to the
provided :class:`.Function`. The resulting form has one
additional :class:`Argument` in the same finite element space as
the Function.
:arg form: a :class:`~ufl.classes.Form` to compute the derivative of.
:arg u: a :class:`.Function` to compute the derivative with
respect to.
:arg du: an optional :class:`Argument` to use as the replacement
in the new form (constructed automatically if not provided).
:arg coefficient_derivatives: an optional :class:`dict` to
provide the derivative of a coefficient function.
:raises ValueError: If any of the coefficients in ``form`` were
obtained from ``u.split()``. UFL doesn't notice that these
are related to ``u`` and so therefore the derivative is
wrong (instead one should have written ``split(u)``).
See also :func:`ufl.derivative`.
"""
if set(extract_coefficients(form)) & set(u.split()):
raise ValueError(
"Taking derivative of form wrt u, but form contains coefficients from u.split()."
"\nYou probably meant to write split(u) when defining your form.")
if du is None:
if isinstance(u, function.Function):
V = u.function_space()
args = form.arguments()
number = max(a.number() for a in args) if args else -1
du = Argument(V, number + 1)
else:
raise RuntimeError("Can't compute derivative for form")
return ufl.derivative(form, u, du, coefficient_derivatives)
def test_extract_coefficients_vs_fixture(coefficients, forms):
assert coefficients == tuple(extract_coefficients(forms[2]))
def compile_ufl_kernel(expression, to_pts, to_element, fs):
import collections
from ufl.algorithms.apply_function_pullbacks import apply_function_pullbacks
from ufl.algorithms.apply_algebra_lowering import apply_algebra_lowering
from ufl.algorithms.apply_derivatives import apply_derivatives
from ufl.algorithms.apply_geometry_lowering import apply_geometry_lowering
from ufl.algorithms import extract_arguments, extract_coefficients
from gem import gem, impero_utils
from tsfc import fem, ufl_utils
from tsfc.coffee import generate as generate_coffee
from tsfc.kernel_interface import (KernelBuilderBase,
needs_cell_orientations,
cell_orientations_coffee_arg)
# Imitate the compute_form_data processing pipeline
#
# Unfortunately, we cannot call compute_form_data here, since
# we only have an expression, not a form
expression = apply_algebra_lowering(expression)
expression = apply_derivatives(expression)
expression = apply_function_pullbacks(expression)
expression = apply_geometry_lowering(expression)
expression = apply_derivatives(expression)
expression = apply_geometry_lowering(expression)
expression = apply_derivatives(expression)
# Replace coordinates (if any)
if expression.ufl_domain():
assert fs.mesh() == expression.ufl_domain()
expression = ufl_utils.replace_coordinates(expression, fs.mesh().coordinates)
if extract_arguments(expression):
return ValueError("Cannot interpolate UFL expression with Arguments!")
builder = KernelBuilderBase()
args = []
coefficients = extract_coefficients(expression)
for i, coefficient in enumerate(coefficients):
args.append(builder.coefficient(coefficient, "w_%d" % i))
point_index = gem.Index(name='p')
ir = fem.process('cell', fs.mesh().ufl_cell(), to_pts, None,
point_index, (), expression,
builder.coefficient_mapper,
collections.defaultdict(gem.Index))
assert len(ir) == 1
# Deal with non-scalar expressions
tensor_indices = ()
if fs.shape:
tensor_indices = tuple(gem.Index() for s in fs.shape)
ir = [gem.Indexed(ir[0], tensor_indices)]
# Build kernel body
return_var = gem.Variable('A', (len(to_pts),) + fs.shape)
return_expr = gem.Indexed(return_var, (point_index,) + tensor_indices)
impero_c = impero_utils.compile_gem([return_expr], ir, [point_index])
body = generate_coffee(impero_c, index_names={point_index: 'p'})
oriented = needs_cell_orientations(ir)
if oriented:
args.insert(0, cell_orientations_coffee_arg)
# Build kernel
args.insert(0, ast.Decl("double", ast.Symbol('A', rank=(len(to_pts),) + fs.shape)))
kernel_code = builder.construct_kernel("expression_kernel", args, body)
return op2.Kernel(kernel_code, kernel_code.name), oriented, coefficients
def compile_ufl_kernel(expression, to_pts, to_element, fs):
import collections
from ufl.algorithms.apply_function_pullbacks import apply_function_pullbacks
from ufl.algorithms.apply_algebra_lowering import apply_algebra_lowering
from ufl.algorithms.apply_derivatives import apply_derivatives
from ufl.algorithms.apply_geometry_lowering import apply_geometry_lowering
from ufl.algorithms import extract_arguments, extract_coefficients
from gem import gem, impero_utils
from tsfc import fem, ufl_utils
from tsfc.coffee import generate as generate_coffee
from tsfc.kernel_interface import (KernelBuilderBase,
needs_cell_orientations,
cell_orientations_coffee_arg)
# Imitate the compute_form_data processing pipeline
#
# Unfortunately, we cannot call compute_form_data here, since
# we only have an expression, not a form
expression = apply_algebra_lowering(expression)
expression = apply_derivatives(expression)
expression = apply_function_pullbacks(expression)
expression = apply_geometry_lowering(expression)
expression = apply_derivatives(expression)
expression = apply_geometry_lowering(expression)
expression = apply_derivatives(expression)
# Replace coordinates (if any)
if expression.ufl_domain():
assert fs.mesh() == expression.ufl_domain()
expression = ufl_utils.replace_coordinates(expression, fs.mesh().coordinates)
if extract_arguments(expression):
return ValueError("Cannot interpolate UFL expression with Arguments!")
builder = KernelBuilderBase()
args = []
coefficients = extract_coefficients(expression)
for i, coefficient in enumerate(coefficients):
args.append(builder.coefficient(coefficient, "w_%d" % i))
point_index = gem.Index(name='p')
ir = fem.compile_ufl(expression,
cell=fs.mesh().ufl_cell(),
points=to_pts,
point_index=point_index,
coefficient_mapper=builder.coefficient_mapper)
assert len(ir) == 1
# Deal with non-scalar expressions
tensor_indices = ()
if fs.shape:
tensor_indices = tuple(gem.Index() for s in fs.shape)
ir = [gem.Indexed(ir[0], tensor_indices)]
# Build kernel body
return_var = gem.Variable('A', (len(to_pts),) + fs.shape)
return_expr = gem.Indexed(return_var, (point_index,) + tensor_indices)
impero_c = impero_utils.compile_gem([return_expr], ir, [point_index])
body = generate_coffee(impero_c, index_names={point_index: 'p'})
oriented = needs_cell_orientations(ir)
if oriented:
args.insert(0, cell_orientations_coffee_arg)
# Build kernel
args.insert(0, ast.Decl("double", ast.Symbol('A', rank=(len(to_pts),) + fs.shape)))
kernel_code = builder.construct_kernel("expression_kernel", args, body)
return op2.Kernel(kernel_code, kernel_code.name), oriented, coefficients
def derivative(form, u, du=None, coefficient_derivatives=None):
"""Compute the derivative of a form.
Given a form, this computes its linearization with respect to the
provided :class:`.Function`. The resulting form has one
additional :class:`Argument` in the same finite element space as
the Function.
:arg form: a :class:`~ufl.classes.Form` to compute the derivative of.
:arg u: a :class:`.Function` to compute the derivative with
respect to.
:arg du: an optional :class:`Argument` to use as the replacement
in the new form (constructed automatically if not provided).
:arg coefficient_derivatives: an optional :class:`dict` to
provide the derivative of a coefficient function.
:raises ValueError: If any of the coefficients in ``form`` were
obtained from ``u.split()``. UFL doesn't notice that these
are related to ``u`` and so therefore the derivative is
wrong (instead one should have written ``split(u)``).
See also :func:`ufl.derivative`.
"""
# TODO: What about Constant?
u_is_x = isinstance(u, ufl.SpatialCoordinate)
if not u_is_x and len(u.split()) > 1 and set(
extract_coefficients(form)) & set(u.split()):
raise ValueError(
"Taking derivative of form wrt u, but form contains coefficients from u.split()."
"\nYou probably meant to write split(u) when defining your form.")
mesh = form.ufl_domain()
is_dX = u_is_x or u is mesh.coordinates
args = form.arguments()
def argument(V):
if du is None:
n = max(a.number() for a in args) if args else -1
return Argument(V, n + 1)
else:
return du
if is_dX:
coords = mesh.coordinates
u = ufl.SpatialCoordinate(mesh)
V = coords.function_space()
du = argument(V)
cds = {coords: du}
if coefficient_derivatives is not None:
cds.update(coefficient_derivatives)
coefficient_derivatives = cds
elif isinstance(u, firedrake.Function):
V = u.function_space()
du = argument(V)
elif isinstance(u, firedrake.Constant):
if u.ufl_shape != ():
raise ValueError(
"Real function space of vector elements not supported")
V = firedrake.FunctionSpace(mesh, "Real", 0)
du = argument(V)
else:
raise RuntimeError("Can't compute derivative for form")
return ufl.derivative(form, u, du, coefficient_derivatives)
def derivative(form, u, du=None, coefficient_derivatives=None):
"""Compute the derivative of a form.
Given a form, this computes its linearization with respect to the
provided :class:`.Function`. The resulting form has one
additional :class:`Argument` in the same finite element space as
the Function.
:arg form: a :class:`~ufl.classes.Form` to compute the derivative of.
:arg u: a :class:`.Function` to compute the derivative with
respect to.
:arg du: an optional :class:`Argument` to use as the replacement
in the new form (constructed automatically if not provided).
:arg coefficient_derivatives: an optional :class:`dict` to
provide the derivative of a coefficient function.
:raises ValueError: If any of the coefficients in ``form`` were
obtained from ``u.split()``. UFL doesn't notice that these
are related to ``u`` and so therefore the derivative is
wrong (instead one should have written ``split(u)``).
See also :func:`ufl.derivative`.
"""
if isinstance(form, firedrake.slate.TensorBase):
raise TypeError(
f"Cannot take the derivative of a {type(form).__name__}"
)
# TODO: What about Constant?
u_is_x = isinstance(u, ufl.SpatialCoordinate)
uc, = (u,) if u_is_x else extract_coefficients(u)
if not u_is_x and len(uc.split()) > 1 and set(extract_coefficients(form)) & set(uc.split()):
raise ValueError("Taking derivative of form wrt u, but form contains coefficients from u.split()."
"\nYou probably meant to write split(u) when defining your form.")
mesh = form.ufl_domain()
if not mesh:
raise ValueError("Expression to be differentiated has no ufl domain."
"\nDo you need to add a domain to your Constant?")
is_dX = u_is_x or u is mesh.coordinates
try:
args = form.arguments()
except AttributeError:
args = extract_arguments(form)
def argument(V):
if du is None:
n = max(a.number() for a in args) if args else -1
return Argument(V, n + 1)
else:
return du
if is_dX:
coords = mesh.coordinates
u = ufl.SpatialCoordinate(mesh)
V = coords.function_space()
du = argument(V)
cds = {coords: du}
if coefficient_derivatives is not None:
cds.update(coefficient_derivatives)
coefficient_derivatives = cds
elif isinstance(uc, firedrake.Function):
V = uc.function_space()
du = argument(V)
elif isinstance(uc, firedrake.Constant):
if uc.ufl_shape != ():
raise ValueError("Real function space of vector elements not supported")
V = firedrake.FunctionSpace(mesh, "Real", 0)
du = argument(V)
else:
raise RuntimeError("Can't compute derivative for form")
if u.ufl_shape != du.ufl_shape:
raise ValueError("Shapes of u and du do not match.\n"
"If you passed an indexed part of split(u) into "
"derivative, you need to provide an appropriate du as well.")
return ufl.derivative(form, u, du, coefficient_derivatives)
def compile_expression_at_points(expression, points, coordinates, parameters=None):
"""Compiles a UFL expression to be evaluated at compile-time known
reference points. Useful for interpolating UFL expressions onto
function spaces with only point evaluation nodes.
:arg expression: UFL expression
:arg points: reference coordinates of the evaluation points
:arg coordinates: the coordinate function
:arg parameters: parameters object
"""
import coffee.base as ast
if parameters is None:
parameters = default_parameters()
else:
_ = default_parameters()
_.update(parameters)
parameters = _
# No arguments, please!
if extract_arguments(expression):
return ValueError("Cannot interpolate UFL expression with Arguments!")
# Apply UFL preprocessing
expression = ufl_utils.preprocess_expression(expression)
# Initialise kernel builder
builder = firedrake_interface.ExpressionKernelBuilder()
# Replace coordinates (if any)
domain = expression.ufl_domain()
if domain:
assert coordinates.ufl_domain() == domain
builder.domain_coordinate[domain] = coordinates
# Collect required coefficients
coefficients = extract_coefficients(expression)
if has_type(expression, GeometricQuantity):
coefficients = [coordinates] + coefficients
builder.set_coefficients(coefficients)
# Split mixed coefficients
expression = ufl_utils.split_coefficients(expression, builder.coefficient_split)
# Translate to GEM
point_set = PointSet(points)
config = dict(interface=builder,
ufl_cell=coordinates.ufl_domain().ufl_cell(),
precision=parameters["precision"],
point_set=point_set)
ir, = fem.compile_ufl(expression, point_sum=False, **config)
# Deal with non-scalar expressions
value_shape = ir.shape
tensor_indices = tuple(gem.Index() for s in value_shape)
if value_shape:
ir = gem.Indexed(ir, tensor_indices)
# Build kernel body
return_shape = (len(points),) + value_shape
return_indices = point_set.indices + tensor_indices
return_var = gem.Variable('A', return_shape)
return_arg = ast.Decl(SCALAR_TYPE, ast.Symbol('A', rank=return_shape))
return_expr = gem.Indexed(return_var, return_indices)
ir, = impero_utils.preprocess_gem([ir])
impero_c = impero_utils.compile_gem([(return_expr, ir)], return_indices)
point_index, = point_set.indices
body = generate_coffee(impero_c, {point_index: 'p'}, parameters["precision"])
# Handle cell orientations
if builder.needs_cell_orientations([ir]):
builder.require_cell_orientations()
# Build kernel tuple
return builder.construct_kernel(return_arg, body)
def derivative(form, u, du=None, coefficient_derivatives=None):
"""Compute the derivative of a form.
Given a form, this computes its linearization with respect to the
provided :class:`.Function`. The resulting form has one
additional :class:`Argument` in the same finite element space as
the Function.
:arg form: a :class:`~ufl.classes.Form` to compute the derivative of.
:arg u: a :class:`.Function` to compute the derivative with
respect to.
:arg du: an optional :class:`Argument` to use as the replacement
in the new form (constructed automatically if not provided).
:arg coefficient_derivatives: an optional :class:`dict` to
provide the derivative of a coefficient function.
:raises ValueError: If any of the coefficients in ``form`` were
obtained from ``u.split()``. UFL doesn't notice that these
are related to ``u`` and so therefore the derivative is
wrong (instead one should have written ``split(u)``).
See also :func:`ufl.derivative`.
"""
# TODO: What about Constant?
u_is_x = isinstance(u, ufl.SpatialCoordinate)
if not u_is_x and len(u.split()) > 1 and set(extract_coefficients(form)) & set(u.split()):
raise ValueError("Taking derivative of form wrt u, but form contains coefficients from u.split()."
"\nYou probably meant to write split(u) when defining your form.")
mesh = form.ufl_domain()
is_dX = u_is_x or u is mesh.coordinates
args = form.arguments()
def argument(V):
if du is None:
n = max(a.number() for a in args) if args else -1
return Argument(V, n + 1)
else:
return du
if is_dX:
coords = mesh.coordinates
u = ufl.SpatialCoordinate(mesh)
V = coords.function_space()
du = argument(V)
cds = {coords: du}
if coefficient_derivatives is not None:
cds.update(coefficient_derivatives)
coefficient_derivatives = cds
elif isinstance(u, firedrake.Function):
V = u.function_space()
du = argument(V)
elif isinstance(u, firedrake.Constant):
if u.ufl_shape != ():
raise ValueError("Real function space of vector elements not supported")
V = firedrake.FunctionSpace(mesh, "Real", 0)
du = argument(V)
else:
raise RuntimeError("Can't compute derivative for form")
return ufl.derivative(form, u, du, coefficient_derivatives)
def compile_expression_at_points(expression,
points,
coordinates,
interface=None,
parameters=None,
coffee=True):
"""Compiles a UFL expression to be evaluated at compile-time known
reference points. Useful for interpolating UFL expressions onto
function spaces with only point evaluation nodes.
:arg expression: UFL expression
:arg points: reference coordinates of the evaluation points
:arg coordinates: the coordinate function
:arg interface: backend module for the kernel interface
:arg parameters: parameters object
:arg coffee: compile coffee kernel instead of loopy kernel
"""
import coffee.base as ast
import loopy as lp
if parameters is None:
parameters = default_parameters()
else:
_ = default_parameters()
_.update(parameters)
parameters = _
# Determine whether in complex mode
complex_mode = is_complex(parameters["scalar_type"])
# Apply UFL preprocessing
expression = ufl_utils.preprocess_expression(expression,
complex_mode=complex_mode)
# Initialise kernel builder
if interface is None:
if coffee:
import tsfc.kernel_interface.firedrake as firedrake_interface_coffee
interface = firedrake_interface_coffee.ExpressionKernelBuilder
else:
# Delayed import, loopy is a runtime dependency
import tsfc.kernel_interface.firedrake_loopy as firedrake_interface_loopy
interface = firedrake_interface_loopy.ExpressionKernelBuilder
builder = interface(parameters["scalar_type"])
arguments = extract_arguments(expression)
argument_multiindices = tuple(
builder.create_element(arg.ufl_element()).get_indices()
for arg in arguments)
# Replace coordinates (if any)
domain = expression.ufl_domain()
if domain:
assert coordinates.ufl_domain() == domain
builder.domain_coordinate[domain] = coordinates
builder.set_cell_sizes(domain)
# Collect required coefficients
coefficients = extract_coefficients(expression)
if has_type(expression, GeometricQuantity) or any(
fem.needs_coordinate_mapping(c.ufl_element())
for c in coefficients):
coefficients = [coordinates] + coefficients
builder.set_coefficients(coefficients)
# Split mixed coefficients
expression = ufl_utils.split_coefficients(expression,
builder.coefficient_split)
# Translate to GEM
point_set = PointSet(points)
config = dict(interface=builder,
ufl_cell=coordinates.ufl_domain().ufl_cell(),
precision=parameters["precision"],
point_set=point_set,
argument_multiindices=argument_multiindices)
ir, = fem.compile_ufl(expression, point_sum=False, **config)
# Deal with non-scalar expressions
value_shape = ir.shape
tensor_indices = tuple(gem.Index() for s in value_shape)
if value_shape:
ir = gem.Indexed(ir, tensor_indices)
# Build kernel body
return_indices = point_set.indices + tensor_indices + tuple(
chain(*argument_multiindices))
return_shape = tuple(i.extent for i in return_indices)
return_var = gem.Variable('A', return_shape)
if coffee:
return_arg = ast.Decl(parameters["scalar_type"],
ast.Symbol('A', rank=return_shape))
else:
return_arg = lp.GlobalArg("A",
dtype=parameters["scalar_type"],
shape=return_shape)
return_expr = gem.Indexed(return_var, return_indices)
ir, = impero_utils.preprocess_gem([ir])
impero_c = impero_utils.compile_gem([(return_expr, ir)], return_indices)
point_index, = point_set.indices
# Handle kernel interface requirements
builder.register_requirements([ir])
# Build kernel tuple
return builder.construct_kernel(return_arg, impero_c,
parameters["precision"],
{point_index: 'p'})
def test_extract_coefficients_vs_fixture(coefficients, forms):
assert coefficients == tuple(extract_coefficients(forms[2]))
def compile_element(expression, coordinates, parameters=None):
"""Generates C code for point evaluations.
:arg expression: UFL expression
:arg coordinates: coordinate field
:arg parameters: form compiler parameters
:returns: C code as string
"""
if parameters is None:
parameters = default_parameters()
else:
_ = default_parameters()
_.update(parameters)
parameters = _
# No arguments, please!
if extract_arguments(expression):
return ValueError("Cannot interpolate UFL expression with Arguments!")
# Apply UFL preprocessing
expression = tsfc.ufl_utils.preprocess_expression(
expression, complex_mode=utils.complex_mode)
# Collect required coefficients
coefficient, = extract_coefficients(expression)
# Point evaluation of mixed coefficients not supported here
if type(coefficient.ufl_element()) == MixedElement:
raise NotImplementedError("Cannot point evaluate mixed elements yet!")
# Replace coordinates (if any)
domain = expression.ufl_domain()
assert coordinates.ufl_domain() == domain
# Initialise kernel builder
builder = firedrake_interface.KernelBuilderBase(utils.ScalarType_c)
builder.domain_coordinate[domain] = coordinates
x_arg = builder._coefficient(coordinates, "x")
f_arg = builder._coefficient(coefficient, "f")
# TODO: restore this for expression evaluation!
# expression = ufl_utils.split_coefficients(expression, builder.coefficient_split)
# Translate to GEM
cell = domain.ufl_cell()
dim = cell.topological_dimension()
point = gem.Variable('X', (dim, ))
point_arg = ast.Decl(utils.ScalarType_c, ast.Symbol('X', rank=(dim, )))
config = dict(interface=builder,
ufl_cell=coordinates.ufl_domain().ufl_cell(),
precision=parameters["precision"],
point_indices=(),
point_expr=point,
complex_mode=utils.complex_mode)
# TODO: restore this for expression evaluation!
# config["cellvolume"] = cellvolume_generator(coordinates.ufl_domain(), coordinates, config)
context = tsfc.fem.GemPointContext(**config)
# Abs-simplification
expression = tsfc.ufl_utils.simplify_abs(expression, utils.complex_mode)
# Translate UFL -> GEM
translator = tsfc.fem.Translator(context)
result, = map_expr_dags(translator, [expression])
tensor_indices = ()
if expression.ufl_shape:
tensor_indices = tuple(gem.Index() for s in expression.ufl_shape)
return_variable = gem.Indexed(gem.Variable('R', expression.ufl_shape),
tensor_indices)
result_arg = ast.Decl(utils.ScalarType_c,
ast.Symbol('R', rank=expression.ufl_shape))
result = gem.Indexed(result, tensor_indices)
else:
return_variable = gem.Indexed(gem.Variable('R', (1, )), (0, ))
result_arg = ast.Decl(utils.ScalarType_c, ast.Symbol('R', rank=(1, )))
# Unroll
max_extent = parameters["unroll_indexsum"]
if max_extent:
def predicate(index):
return index.extent <= max_extent
result, = gem.optimise.unroll_indexsum([result], predicate=predicate)
# Translate GEM -> COFFEE
result, = gem.impero_utils.preprocess_gem([result])
impero_c = gem.impero_utils.compile_gem([(return_variable, result)],
tensor_indices)
body = generate_coffee(impero_c, {}, parameters["precision"],
utils.ScalarType_c)
# Build kernel tuple
kernel_code = builder.construct_kernel(
"evaluate_kernel", [result_arg, point_arg, x_arg, f_arg], body)
# Fill the code template
extruded = isinstance(cell, TensorProductCell)
code = {
"geometric_dimension": cell.geometric_dimension(),
"layers_arg": ", int const *__restrict__ layers" if extruded else "",
"layers": ", layers" if extruded else "",
"IntType": as_cstr(IntType),
"scalar_type": utils.ScalarType_c,
}
# if maps are the same, only need to pass one of them
if coordinates.cell_node_map() == coefficient.cell_node_map():
code[
"wrapper_map_args"] = "%(IntType)s const *__restrict__ coords_map" % code
code["map_args"] = "f->coords_map"
else:
code[
"wrapper_map_args"] = "%(IntType)s const *__restrict__ coords_map, %(IntType)s const *__restrict__ f_map" % code
code["map_args"] = "f->coords_map, f->f_map"
evaluate_template_c = """
static inline void wrap_evaluate(%(scalar_type)s* const result, %(scalar_type)s* const X, int const start, int const end%(layers_arg)s,
%(scalar_type)s const *__restrict__ coords, %(scalar_type)s const *__restrict__ f, %(wrapper_map_args)s);
int evaluate(struct Function *f, %(scalar_type)s *x, %(scalar_type)s *result)
{
struct ReferenceCoords reference_coords;
%(IntType)s cell = locate_cell(f, x, %(geometric_dimension)d, &to_reference_coords, &to_reference_coords_xtr, &reference_coords);
if (cell == -1) {
return -1;
}
if (!result) {
return 0;
}
int layers[2] = {0, 0};
if (f->extruded != 0) {
int nlayers = f->n_layers;
layers[1] = cell %% nlayers + 2;
cell = cell / nlayers;
}
wrap_evaluate(result, reference_coords.X, cell, cell+1%(layers)s, f->coords, f->f, %(map_args)s);
return 0;
}
"""
return (evaluate_template_c % code) + kernel_code.gencode()
def compile_expression_dual_evaluation(expression,
to_element,
*,
domain=None,
interface=None,
parameters=None,
coffee=False):
"""Compile a UFL expression to be evaluated against a compile-time known reference element's dual basis.
Useful for interpolating UFL expressions into e.g. N1curl spaces.
:arg expression: UFL expression
:arg to_element: A FInAT element for the target space
:arg domain: optional UFL domain the expression is defined on (required when expression contains no domain).
:arg interface: backend module for the kernel interface
:arg parameters: parameters object
:arg coffee: compile coffee kernel instead of loopy kernel
"""
import coffee.base as ast
import loopy as lp
# Just convert FInAT element to FIAT for now.
# Dual evaluation in FInAT will bring a thorough revision.
to_element = to_element.fiat_equivalent
if any(len(dual.deriv_dict) != 0 for dual in to_element.dual_basis()):
raise NotImplementedError(
"Can only interpolate onto dual basis functionals without derivative evaluation, sorry!"
)
if parameters is None:
parameters = default_parameters()
else:
_ = default_parameters()
_.update(parameters)
parameters = _
# Determine whether in complex mode
complex_mode = is_complex(parameters["scalar_type"])
# Find out which mapping to apply
try:
mapping, = set(to_element.mapping())
except ValueError:
raise NotImplementedError(
"Don't know how to interpolate onto zany spaces, sorry")
expression = apply_mapping(expression, mapping, domain)
# Apply UFL preprocessing
expression = ufl_utils.preprocess_expression(expression,
complex_mode=complex_mode)
# Initialise kernel builder
if interface is None:
if coffee:
import tsfc.kernel_interface.firedrake as firedrake_interface_coffee
interface = firedrake_interface_coffee.ExpressionKernelBuilder
else:
# Delayed import, loopy is a runtime dependency
import tsfc.kernel_interface.firedrake_loopy as firedrake_interface_loopy
interface = firedrake_interface_loopy.ExpressionKernelBuilder
builder = interface(parameters["scalar_type"])
arguments = extract_arguments(expression)
argument_multiindices = tuple(
builder.create_element(arg.ufl_element()).get_indices()
for arg in arguments)
# Replace coordinates (if any) unless otherwise specified by kwarg
if domain is None:
domain = expression.ufl_domain()
assert domain is not None
# Collect required coefficients
first_coefficient_fake_coords = False
coefficients = extract_coefficients(expression)
if has_type(expression, GeometricQuantity) or any(
fem.needs_coordinate_mapping(c.ufl_element())
for c in coefficients):
# Create a fake coordinate coefficient for a domain.
coords_coefficient = ufl.Coefficient(
ufl.FunctionSpace(domain, domain.ufl_coordinate_element()))
builder.domain_coordinate[domain] = coords_coefficient
builder.set_cell_sizes(domain)
coefficients = [coords_coefficient] + coefficients
first_coefficient_fake_coords = True
builder.set_coefficients(coefficients)
# Split mixed coefficients
expression = ufl_utils.split_coefficients(expression,
builder.coefficient_split)
# Translate to GEM
kernel_cfg = dict(
interface=builder,
ufl_cell=domain.ufl_cell(),
# FIXME: change if we ever implement
# interpolation on facets.
integral_type="cell",
argument_multiindices=argument_multiindices,
index_cache={},
scalar_type=parameters["scalar_type"])
if all(
isinstance(dual, PointEvaluation)
for dual in to_element.dual_basis()):
# This is an optimisation for point-evaluation nodes which
# should go away once FInAT offers the interface properly
qpoints = []
# Everything is just a point evaluation.
for dual in to_element.dual_basis():
ptdict = dual.get_point_dict()
qpoint, = ptdict.keys()
(qweight, component), = ptdict[qpoint]
assert allclose(qweight, 1.0)
assert component == ()
qpoints.append(qpoint)
point_set = PointSet(qpoints)
config = kernel_cfg.copy()
config.update(point_set=point_set)
# Allow interpolation onto QuadratureElements to refer to the quadrature
# rule they represent
if isinstance(to_element, FIAT.QuadratureElement):
assert allclose(asarray(qpoints), asarray(to_element._points))
quad_rule = QuadratureRule(point_set, to_element._weights)
config["quadrature_rule"] = quad_rule
expr, = fem.compile_ufl(expression, **config, point_sum=False)
# In some cases point_set.indices may be dropped from expr, but nothing
# new should now appear
assert set(expr.free_indices) <= set(
chain(point_set.indices, *argument_multiindices))
shape_indices = tuple(gem.Index() for _ in expr.shape)
basis_indices = point_set.indices
ir = gem.Indexed(expr, shape_indices)
else:
# This is general code but is more unrolled than necssary.
dual_expressions = [] # one for each functional
broadcast_shape = len(expression.ufl_shape) - len(
to_element.value_shape())
shape_indices = tuple(gem.Index()
for _ in expression.ufl_shape[:broadcast_shape])
expr_cache = {} # Sharing of evaluation of the expression at points
for dual in to_element.dual_basis():
pts = tuple(sorted(dual.get_point_dict().keys()))
try:
expr, point_set = expr_cache[pts]
except KeyError:
point_set = PointSet(pts)
config = kernel_cfg.copy()
config.update(point_set=point_set)
expr, = fem.compile_ufl(expression, **config, point_sum=False)
# In some cases point_set.indices may be dropped from expr, but
# nothing new should now appear
assert set(expr.free_indices) <= set(
chain(point_set.indices, *argument_multiindices))
expr = gem.partial_indexed(expr, shape_indices)
expr_cache[pts] = expr, point_set
weights = collections.defaultdict(list)
for p in pts:
for (w, cmp) in dual.get_point_dict()[p]:
weights[cmp].append(w)
qexprs = gem.Zero()
for cmp in sorted(weights):
qweights = gem.Literal(weights[cmp])
qexpr = gem.Indexed(expr, cmp)
qexpr = gem.index_sum(
gem.Indexed(qweights, point_set.indices) * qexpr,
point_set.indices)
qexprs = gem.Sum(qexprs, qexpr)
assert qexprs.shape == ()
assert set(qexprs.free_indices) == set(
chain(shape_indices, *argument_multiindices))
dual_expressions.append(qexprs)
basis_indices = (gem.Index(), )
ir = gem.Indexed(gem.ListTensor(dual_expressions), basis_indices)
# Build kernel body
return_indices = basis_indices + shape_indices + tuple(
chain(*argument_multiindices))
return_shape = tuple(i.extent for i in return_indices)
return_var = gem.Variable('A', return_shape)
if coffee:
return_arg = ast.Decl(parameters["scalar_type"],
ast.Symbol('A', rank=return_shape))
else:
return_arg = lp.GlobalArg("A",
dtype=parameters["scalar_type"],
shape=return_shape)
return_expr = gem.Indexed(return_var, return_indices)
# TODO: one should apply some GEM optimisations as in assembly,
# but we don't for now.
ir, = impero_utils.preprocess_gem([ir])
impero_c = impero_utils.compile_gem([(return_expr, ir)], return_indices)
index_names = dict(
(idx, "p%d" % i) for (i, idx) in enumerate(basis_indices))
# Handle kernel interface requirements
builder.register_requirements([ir])
# Build kernel tuple
return builder.construct_kernel(return_arg, impero_c, index_names,
first_coefficient_fake_coords)
def compile_element(expression, coordinates, parameters=None):
"""Generates C code for point evaluations.
:arg expression: UFL expression
:arg coordinates: coordinate field
:arg parameters: form compiler parameters
:returns: C code as string
"""
if parameters is None:
parameters = default_parameters()
else:
_ = default_parameters()
_.update(parameters)
parameters = _
# No arguments, please!
if extract_arguments(expression):
return ValueError("Cannot interpolate UFL expression with Arguments!")
# Apply UFL preprocessing
expression = tsfc.ufl_utils.preprocess_expression(expression)
# Collect required coefficients
coefficient, = extract_coefficients(expression)
# Point evaluation of mixed coefficients not supported here
if type(coefficient.ufl_element()) == MixedElement:
raise NotImplementedError("Cannot point evaluate mixed elements yet!")
# Replace coordinates (if any)
domain = expression.ufl_domain()
assert coordinates.ufl_domain() == domain
expression = tsfc.ufl_utils.replace_coordinates(expression, coordinates)
# Initialise kernel builder
builder = firedrake_interface.KernelBuilderBase()
x_arg = builder._coefficient(coordinates, "x")
f_arg = builder._coefficient(coefficient, "f")
# TODO: restore this for expression evaluation!
# expression = ufl_utils.split_coefficients(expression, builder.coefficient_split)
# Translate to GEM
cell = domain.ufl_cell()
dim = cell.topological_dimension()
point = gem.Variable('X', (dim, ))
point_arg = ast.Decl(SCALAR_TYPE, ast.Symbol('X', rank=(dim, )))
config = dict(interface=builder,
ufl_cell=coordinates.ufl_domain().ufl_cell(),
precision=parameters["precision"],
point_indices=(),
point_expr=point)
# TODO: restore this for expression evaluation!
# config["cellvolume"] = cellvolume_generator(coordinates.ufl_domain(), coordinates, config)
context = tsfc.fem.GemPointContext(**config)
# Abs-simplification
expression = tsfc.ufl_utils.simplify_abs(expression)
# Translate UFL -> GEM
translator = tsfc.fem.Translator(context)
result, = map_expr_dags(translator, [expression])
tensor_indices = ()
if expression.ufl_shape:
tensor_indices = tuple(gem.Index() for s in expression.ufl_shape)
return_variable = gem.Indexed(gem.Variable('R', expression.ufl_shape),
tensor_indices)
result_arg = ast.Decl(SCALAR_TYPE,
ast.Symbol('R', rank=expression.ufl_shape))
result = gem.Indexed(result, tensor_indices)
else:
return_variable = gem.Indexed(gem.Variable('R', (1, )), (0, ))
result_arg = ast.Decl(SCALAR_TYPE, ast.Symbol('R', rank=(1, )))
# Unroll
max_extent = parameters["unroll_indexsum"]
if max_extent:
def predicate(index):
return index.extent <= max_extent
result, = gem.optimise.unroll_indexsum([result], predicate=predicate)
# Translate GEM -> COFFEE
result, = gem.impero_utils.preprocess_gem([result])
impero_c = gem.impero_utils.compile_gem([(return_variable, result)],
tensor_indices)
body = generate_coffee(impero_c, {}, parameters["precision"])
# Build kernel tuple
kernel_code = builder.construct_kernel(
"evaluate_kernel", [result_arg, point_arg, x_arg, f_arg], body)
# Fill the code template
extruded = isinstance(cell, TensorProductCell)
#code = {
#"geometric_dimension": cell.geometric_dimension(),
#"extruded_arg": ", %s nlayers" % as_cstr(IntType) if extruded else "",
#"nlayers": ", f->n_layers" if extruded else "",
#"IntType": as_cstr(IntType),
#}
#evaluate_template_c = """static inline void wrap_evaluate(double *result, double *X, double *coords, %(IntType)s *coords_map, double *f, %(IntType)s *f_map%(extruded_arg)s, %(IntType)s cell);
#int evaluate(struct Function *f, double *x, double *result)
#{
#struct ReferenceCoords reference_coords;
#%(IntType)s cell = locate_cell(f, x, %(geometric_dimension)d, &to_reference_coords, &reference_coords);
#if (cell == -1) {
#return -1;
#}
#if (!result) {
#return 0;
#}
#wrap_evaluate(result, reference_coords.X, f->coords, f->coords_map, f->f, f->f_map%(nlayers)s, cell);
#return 0;
#}
#"""
# return (evaluate_template_c % code) + kernel_code.gencode()
return kernel_code.gencode()
def compute_expression_ir(expression, analysis, parameters, visualise):
"""Compute IR for expression.
Parameters
----------
expression
Triple of (UFL expression, array of evaluation points, original UFL expression).
Note
----
Original UFL expression is needed to compute original positions of coefficients.
"""
logger.info("Computing uflacs representation of expression")
original_expression = expression[2]
points = expression[1]
expression = expression[0]
num_points = points.shape[0]
weights = numpy.array([1.0] * num_points)
cell = expression.ufl_domain().ufl_cell()
ir = {}
# Prepare dimensions of all unique element in expression,
# including elements for arguments, coefficients and coordinate mappings
ir["element_dimensions"] = {
ufl_element: create_element(ufl_element).space_dimension()
for ufl_element in analysis.unique_elements
}
# Extract dimensions for elements of arguments only
arguments = extract_arguments(expression)
argument_elements = tuple(f.ufl_element() for f in arguments)
argument_dimensions = [
ir["element_dimensions"][ufl_element]
for ufl_element in argument_elements
]
tensor_shape = argument_dimensions
ir["tensor_shape"] = tensor_shape
ir["expression_shape"] = list(expression.ufl_shape)
coefficients = extract_coefficients(expression)
coefficient_numbering = {}
for i, coeff in enumerate(coefficients):
coefficient_numbering[coeff] = i
# Add coefficient numbering to IR
ir["coefficient_numbering"] = coefficient_numbering
original_coefficient_positions = []
original_coefficients = extract_coefficients(original_expression)
for coeff in coefficients:
original_coefficient_positions.append(
original_coefficients.index(coeff))
ir["original_coefficient_positions"] = original_coefficient_positions
coefficient_elements = tuple(f.ufl_element() for f in coefficients)
offsets = {}
_offset = 0
for i, el in enumerate(coefficient_elements):
offsets[coefficients[i]] = _offset
_offset += ir["element_dimensions"][el]
# Copy offsets also into IR
ir["coefficient_offsets"] = offsets
ir["integral_type"] = "expression"
ir["entitytype"] = "cell"
# Build offsets for Constants
original_constant_offsets = {}
_offset = 0
for constant in extract_constants(expression):
original_constant_offsets[constant] = _offset
_offset += numpy.product(constant.ufl_shape, dtype=numpy.int)
ir["original_constant_offsets"] = original_constant_offsets
ir["points"] = points
integrands = {num_points: expression}
quadrature_rules = {num_points: (points, weights)}
uflacs_ir = build_uflacs_ir(cell, ir["integral_type"], ir["entitytype"],
integrands, tensor_shape, quadrature_rules,
parameters, visualise)
ir.update(uflacs_ir)
return ir
def compile_element(expression, coordinates, parameters=None):
"""Generates C code for point evaluations.
:arg expression: UFL expression
:arg coordinates: coordinate field
:arg parameters: form compiler parameters
:returns: C code as string
"""
if parameters is None:
parameters = default_parameters()
else:
_ = default_parameters()
_.update(parameters)
parameters = _
# No arguments, please!
if extract_arguments(expression):
return ValueError("Cannot interpolate UFL expression with Arguments!")
# Apply UFL preprocessing
expression = tsfc.ufl_utils.preprocess_expression(expression)
# Collect required coefficients
coefficient, = extract_coefficients(expression)
# Point evaluation of mixed coefficients not supported here
if type(coefficient.ufl_element()) == MixedElement:
raise NotImplementedError("Cannot point evaluate mixed elements yet!")
# Replace coordinates (if any)
domain = expression.ufl_domain()
assert coordinates.ufl_domain() == domain
# Initialise kernel builder
builder = firedrake_interface.KernelBuilderBase()
builder.domain_coordinate[domain] = coordinates
x_arg = builder._coefficient(coordinates, "x")
f_arg = builder._coefficient(coefficient, "f")
# TODO: restore this for expression evaluation!
# expression = ufl_utils.split_coefficients(expression, builder.coefficient_split)
# Translate to GEM
cell = domain.ufl_cell()
dim = cell.topological_dimension()
point = gem.Variable('X', (dim,))
point_arg = ast.Decl(SCALAR_TYPE, ast.Symbol('X', rank=(dim,)))
config = dict(interface=builder,
ufl_cell=coordinates.ufl_domain().ufl_cell(),
precision=parameters["precision"],
point_indices=(),
point_expr=point)
# TODO: restore this for expression evaluation!
# config["cellvolume"] = cellvolume_generator(coordinates.ufl_domain(), coordinates, config)
context = tsfc.fem.GemPointContext(**config)
# Abs-simplification
expression = tsfc.ufl_utils.simplify_abs(expression)
# Translate UFL -> GEM
translator = tsfc.fem.Translator(context)
result, = map_expr_dags(translator, [expression])
tensor_indices = ()
if expression.ufl_shape:
tensor_indices = tuple(gem.Index() for s in expression.ufl_shape)
return_variable = gem.Indexed(gem.Variable('R', expression.ufl_shape), tensor_indices)
result_arg = ast.Decl(SCALAR_TYPE, ast.Symbol('R', rank=expression.ufl_shape))
result = gem.Indexed(result, tensor_indices)
else:
return_variable = gem.Indexed(gem.Variable('R', (1,)), (0,))
result_arg = ast.Decl(SCALAR_TYPE, ast.Symbol('R', rank=(1,)))
# Unroll
max_extent = parameters["unroll_indexsum"]
if max_extent:
def predicate(index):
return index.extent <= max_extent
result, = gem.optimise.unroll_indexsum([result], predicate=predicate)
# Translate GEM -> COFFEE
result, = gem.impero_utils.preprocess_gem([result])
impero_c = gem.impero_utils.compile_gem([(return_variable, result)], tensor_indices)
body = generate_coffee(impero_c, {}, parameters["precision"])
# Build kernel tuple
kernel_code = builder.construct_kernel("evaluate_kernel", [result_arg, point_arg, x_arg, f_arg], body)
# Fill the code template
extruded = isinstance(cell, TensorProductCell)
code = {
"geometric_dimension": cell.geometric_dimension(),
"layers_arg": ", int const *__restrict__ layers" if extruded else "",
"layers": ", layers" if extruded else "",
"IntType": as_cstr(IntType),
}
# if maps are the same, only need to pass one of them
if coordinates.cell_node_map() == coefficient.cell_node_map():
code["wrapper_map_args"] = "%(IntType)s const *__restrict__ coords_map" % code
code["map_args"] = "f->coords_map"
else:
code["wrapper_map_args"] = "%(IntType)s const *__restrict__ coords_map, %(IntType)s const *__restrict__ f_map" % code
code["map_args"] = "f->coords_map, f->f_map"
evaluate_template_c = """
static inline void wrap_evaluate(double* const result, double* const X, int const start, int const end%(layers_arg)s,
double const *__restrict__ coords, double const *__restrict__ f, %(wrapper_map_args)s);
int evaluate(struct Function *f, double *x, double *result)
{
struct ReferenceCoords reference_coords;
%(IntType)s cell = locate_cell(f, x, %(geometric_dimension)d, &to_reference_coords, &to_reference_coords_xtr, &reference_coords);
if (cell == -1) {
return -1;
}
if (!result) {
return 0;
}
int layers[2] = {0, 0};
if (f->extruded != 0) {
int nlayers = f->n_layers;
layers[1] = cell %% nlayers + 2;
cell = cell / nlayers;
}
wrap_evaluate(result, reference_coords.X, cell, cell+1%(layers)s, f->coords, f->f, %(map_args)s);
return 0;
}
"""
return (evaluate_template_c % code) + kernel_code.gencode()
