raise ValueError("point must be a non-negative integer")
self[point] = Value.wrap(enabled)
- def like(self, name=None, src_loc_at=0):
+ def like(self, name=None, src_loc_at=0, mul=1):
"""Create a new ``PartitionPoints`` with ``Signal``s for all values.
:param name: the base name for the new ``Signal``s.
+ :param mul: a multiplication factor on the indices
"""
if name is None:
name = Signal(src_loc_at=1+src_loc_at).name # get variable name
retval = PartitionPoints()
for point, enabled in self.items():
+ point *= mul
retval[point] = Signal(enabled.shape(), name=f"{name}_{point}")
return retval
return False
return True
+ def part_byte(self, index, mfactor=1): # mfactor used for "expanding"
+ if index == -1 or index == 7:
+ return C(True, 1)
+ assert index >= 0 and index < 8
+ return self[(index * 8 + 8)*mfactor]
+
class FullAdder(Elaboratable):
"""Full Adder.
FULL_ADDER_INPUT_COUNT = 3
+class AddReduceData:
+
+ def __init__(self, ppoints, n_inputs, output_width, n_parts):
+ self.part_ops = [Signal(2, name=f"part_ops_{i}")
+ for i in range(n_parts)]
+ self.inputs = [Signal(output_width, name=f"inputs[{i}]")
+ for i in range(n_inputs)]
+ self.reg_partition_points = ppoints.like()
+
+ def eq_from(self, reg_partition_points, inputs, part_ops):
+ return [self.reg_partition_points.eq(reg_partition_points)] + \
+ [self.inputs[i].eq(inputs[i])
+ for i in range(len(self.inputs))] + \
+ [self.part_ops[i].eq(part_ops[i])
+ for i in range(len(self.part_ops))]
+
+ def eq(self, rhs):
+ return self.eq_from(rhs.reg_partition_points, rhs.inputs, rhs.part_ops)
+
+
+class FinalReduceData:
+
+ def __init__(self, ppoints, output_width, n_parts):
+ self.part_ops = [Signal(2, name=f"part_ops_{i}")
+ for i in range(n_parts)]
+ self.output = Signal(output_width)
+ self.reg_partition_points = ppoints.like()
+
+ def eq_from(self, reg_partition_points, output, part_ops):
+ return [self.reg_partition_points.eq(reg_partition_points)] + \
+ [self.output.eq(output)] + \
+ [self.part_ops[i].eq(part_ops[i])
+ for i in range(len(self.part_ops))]
+
+ def eq(self, rhs):
+ return self.eq_from(rhs.reg_partition_points, rhs.output, rhs.part_ops)
+
+
+class FinalAdd(Elaboratable):
+ """ Final stage of add reduce
+ """
+
+ def __init__(self, n_inputs, output_width, n_parts, register_levels,
+ partition_points):
+ self.i = AddReduceData(partition_points, n_inputs,
+ output_width, n_parts)
+ self.o = FinalReduceData(partition_points, output_width, n_parts)
+ self.output_width = output_width
+ self.n_inputs = n_inputs
+ self.n_parts = n_parts
+ self.register_levels = list(register_levels)
+ self.partition_points = PartitionPoints(partition_points)
+ if not self.partition_points.fits_in_width(output_width):
+ raise ValueError("partition_points doesn't fit in output_width")
+
+ def elaborate(self, platform):
+ """Elaborate this module."""
+ m = Module()
+
+ output_width = self.output_width
+ output = Signal(output_width)
+ if self.n_inputs == 0:
+ # use 0 as the default output value
+ m.d.comb += output.eq(0)
+ elif self.n_inputs == 1:
+ # handle single input
+ m.d.comb += output.eq(self.i.inputs[0])
+ else:
+ # base case for adding 2 inputs
+ assert self.n_inputs == 2
+ adder = PartitionedAdder(output_width, self.i.reg_partition_points)
+ m.submodules.final_adder = adder
+ m.d.comb += adder.a.eq(self.i.inputs[0])
+ m.d.comb += adder.b.eq(self.i.inputs[1])
+ m.d.comb += output.eq(adder.output)
+
+ # create output
+ m.d.comb += self.o.eq_from(self.i.reg_partition_points, output,
+ self.i.part_ops)
+
+ return m
+
class AddReduceSingle(Elaboratable):
"""Add list of numbers together.
supported, except for by ``Signal.eq``.
"""
- def __init__(self, inputs, output_width, register_levels, partition_points,
- part_ops):
+ def __init__(self, n_inputs, output_width, n_parts, register_levels,
+ partition_points):
"""Create an ``AddReduce``.
:param inputs: input ``Signal``s to be summed.
pipeline registers.
:param partition_points: the input partition points.
"""
- self.part_ops = part_ops
- self.out_part_ops = [Signal(2, name=f"out_part_ops_{i}")
- for i in range(len(part_ops))]
- self.inputs = list(inputs)
- self._resized_inputs = [
- Signal(output_width, name=f"resized_inputs[{i}]")
- for i in range(len(self.inputs))]
+ self.n_inputs = n_inputs
+ self.n_parts = n_parts
+ self.output_width = output_width
+ self.i = AddReduceData(partition_points, n_inputs,
+ output_width, n_parts)
self.register_levels = list(register_levels)
- self.output = Signal(output_width)
self.partition_points = PartitionPoints(partition_points)
if not self.partition_points.fits_in_width(output_width):
raise ValueError("partition_points doesn't fit in output_width")
- self._reg_partition_points = self.partition_points.like()
- max_level = AddReduceSingle.get_max_level(len(self.inputs))
+ max_level = AddReduceSingle.get_max_level(n_inputs)
for level in self.register_levels:
if level > max_level:
raise ValueError(
# because we need to know what they are (in order to set up the
# interconnects back in AddReduce), but cannot do the m.d.comb +=
# etc because this is not in elaboratable.
- self.groups = AddReduceSingle.full_adder_groups(len(self.inputs))
+ self.groups = AddReduceSingle.full_adder_groups(n_inputs)
self._intermediate_terms = []
+ self.adders = []
if len(self.groups) != 0:
self.create_next_terms()
+ self.o = AddReduceData(partition_points, len(self._intermediate_terms),
+ output_width, n_parts)
+
@staticmethod
def get_max_level(input_count):
"""Get the maximum level.
"""Elaborate this module."""
m = Module()
- # resize inputs to correct bit-width and optionally add in
- # pipeline registers
- resized_input_assignments = [self._resized_inputs[i].eq(self.inputs[i])
- for i in range(len(self.inputs))]
- copy_part_ops = [self.out_part_ops[i].eq(self.part_ops[i])
- for i in range(len(self.part_ops))]
- if 0 in self.register_levels:
- m.d.sync += copy_part_ops
- m.d.sync += resized_input_assignments
- m.d.sync += self._reg_partition_points.eq(self.partition_points)
- else:
- m.d.comb += copy_part_ops
- m.d.comb += resized_input_assignments
- m.d.comb += self._reg_partition_points.eq(self.partition_points)
-
- for (value, term) in self._intermediate_terms:
- m.d.comb += term.eq(value)
-
- # if there are no full adders to create, then we handle the base cases
- # and return, otherwise we go on to the recursive case
- if len(self.groups) == 0:
- if len(self.inputs) == 0:
- # use 0 as the default output value
- m.d.comb += self.output.eq(0)
- elif len(self.inputs) == 1:
- # handle single input
- m.d.comb += self.output.eq(self._resized_inputs[0])
- else:
- # base case for adding 2 inputs
- assert len(self.inputs) == 2
- adder = PartitionedAdder(len(self.output),
- self._reg_partition_points)
- m.submodules.final_adder = adder
- m.d.comb += adder.a.eq(self._resized_inputs[0])
- m.d.comb += adder.b.eq(self._resized_inputs[1])
- m.d.comb += self.output.eq(adder.output)
- return m
-
- mask = self._reg_partition_points.as_mask(len(self.output))
- m.d.comb += self.part_mask.eq(mask)
+ # copy the intermediate terms to the output
+ for i, value in enumerate(self._intermediate_terms):
+ m.d.comb += self.o.inputs[i].eq(value)
+
+ # copy reg part points and part ops to output
+ m.d.comb += self.o.reg_partition_points.eq(self.i.reg_partition_points)
+ m.d.comb += [self.o.part_ops[i].eq(self.i.part_ops[i])
+ for i in range(len(self.i.part_ops))]
+
+ # set up the partition mask (for the adders)
+ part_mask = Signal(self.output_width, reset_less=True)
+
+ mask = self.i.reg_partition_points.as_mask(self.output_width)
+ m.d.comb += part_mask.eq(mask)
# add and link the intermediate term modules
for i, (iidx, adder_i) in enumerate(self.adders):
setattr(m.submodules, f"adder_{i}", adder_i)
- m.d.comb += adder_i.in0.eq(self._resized_inputs[iidx])
- m.d.comb += adder_i.in1.eq(self._resized_inputs[iidx + 1])
- m.d.comb += adder_i.in2.eq(self._resized_inputs[iidx + 2])
- m.d.comb += adder_i.mask.eq(self.part_mask)
+ m.d.comb += adder_i.in0.eq(self.i.inputs[iidx])
+ m.d.comb += adder_i.in1.eq(self.i.inputs[iidx + 1])
+ m.d.comb += adder_i.in2.eq(self.i.inputs[iidx + 2])
+ m.d.comb += adder_i.mask.eq(part_mask)
return m
def create_next_terms(self):
- # go on to prepare recursive case
- intermediate_terms = []
_intermediate_terms = []
def add_intermediate_term(value):
- intermediate_term = Signal(
- len(self.output),
- name=f"intermediate_terms[{len(intermediate_terms)}]")
- _intermediate_terms.append((value, intermediate_term))
- intermediate_terms.append(intermediate_term)
-
- # store mask in intermediary (simplifies graph)
- self.part_mask = Signal(len(self.output), reset_less=True)
+ _intermediate_terms.append(value)
# create full adders for this recursive level.
# this shrinks N terms to 2 * (N // 3) plus the remainder
- self.adders = []
for i in self.groups:
- adder_i = MaskedFullAdder(len(self.output))
+ adder_i = MaskedFullAdder(self.output_width)
self.adders.append((i, adder_i))
# add both the sum and the masked-carry to the next level.
# 3 inputs have now been reduced to 2...
add_intermediate_term(adder_i.sum)
add_intermediate_term(adder_i.mcarry)
# handle the remaining inputs.
- if len(self.inputs) % FULL_ADDER_INPUT_COUNT == 1:
- add_intermediate_term(self._resized_inputs[-1])
- elif len(self.inputs) % FULL_ADDER_INPUT_COUNT == 2:
+ if self.n_inputs % FULL_ADDER_INPUT_COUNT == 1:
+ add_intermediate_term(self.i.inputs[-1])
+ elif self.n_inputs % FULL_ADDER_INPUT_COUNT == 2:
# Just pass the terms to the next layer, since we wouldn't gain
# anything by using a half adder since there would still be 2 terms
# and just passing the terms to the next layer saves gates.
- add_intermediate_term(self._resized_inputs[-2])
- add_intermediate_term(self._resized_inputs[-1])
+ add_intermediate_term(self.i.inputs[-2])
+ add_intermediate_term(self.i.inputs[-1])
else:
- assert len(self.inputs) % FULL_ADDER_INPUT_COUNT == 0
+ assert self.n_inputs % FULL_ADDER_INPUT_COUNT == 0
- self.intermediate_terms = intermediate_terms
self._intermediate_terms = _intermediate_terms
"""
self.inputs = inputs
self.part_ops = part_ops
- self.out_part_ops = [Signal(2, name=f"out_part_ops_{i}")
- for i in range(len(part_ops))]
- self.output = Signal(output_width)
+ n_parts = len(part_ops)
+ self.o = FinalReduceData(partition_points, output_width, n_parts)
self.output_width = output_width
self.register_levels = register_levels
self.partition_points = partition_points
mods = []
next_levels = self.register_levels
partition_points = self.partition_points
- inputs = self.inputs
part_ops = self.part_ops
+ n_parts = len(part_ops)
+ inputs = self.inputs
+ ilen = len(inputs)
while True:
- next_level = AddReduceSingle(inputs, self.output_width, next_levels,
- partition_points, part_ops)
+ next_level = AddReduceSingle(ilen, self.output_width, n_parts,
+ next_levels, partition_points)
mods.append(next_level)
- if len(next_level.groups) == 0:
- break
next_levels = list(AddReduce.next_register_levels(next_levels))
- partition_points = next_level._reg_partition_points
- inputs = next_level.intermediate_terms
- part_ops = next_level.out_part_ops
+ partition_points = next_level.i.reg_partition_points
+ inputs = next_level.o.inputs
+ ilen = len(inputs)
+ part_ops = next_level.i.part_ops
+ groups = AddReduceSingle.full_adder_groups(len(inputs))
+ if len(groups) == 0:
+ break
+
+ next_level = FinalAdd(ilen, self.output_width, n_parts,
+ next_levels, partition_points)
+ mods.append(next_level)
self.levels = mods
for i, next_level in enumerate(self.levels):
setattr(m.submodules, "next_level%d" % i, next_level)
+ partition_points = self.partition_points
+ inputs = self.inputs
+ part_ops = self.part_ops
+ n_parts = len(part_ops)
+ n_inputs = len(inputs)
+ output_width = self.output_width
+ i = AddReduceData(partition_points, n_inputs, output_width, n_parts)
+ m.d.comb += i.eq_from(partition_points, inputs, part_ops)
+ for idx in range(len(self.levels)):
+ mcur = self.levels[idx]
+ if 0 in mcur.register_levels:
+ m.d.sync += mcur.i.eq(i)
+ else:
+ m.d.comb += mcur.i.eq(i)
+ i = mcur.o # for next loop
+
# output comes from last module
- m.d.comb += self.output.eq(next_level.output)
- copy_part_ops = [self.out_part_ops[i].eq(next_level.out_part_ops[i])
- for i in range(len(self.part_ops))]
- m.d.comb += copy_part_ops
+ m.d.comb += self.o.eq(i)
return m
return m
+class Parts(Elaboratable):
+
+ def __init__(self, pbwid, epps, n_parts):
+ self.pbwid = pbwid
+ # inputs
+ self.epps = PartitionPoints.like(epps, name="epps") # expanded points
+ # outputs
+ self.parts = [Signal(name=f"part_{i}") for i in range(n_parts)]
+
+ def elaborate(self, platform):
+ m = Module()
+
+ epps, parts = self.epps, self.parts
+ # collect part-bytes (double factor because the input is extended)
+ pbs = Signal(self.pbwid, reset_less=True)
+ tl = []
+ for i in range(self.pbwid):
+ pb = Signal(name="pb%d" % i, reset_less=True)
+ m.d.comb += pb.eq(epps.part_byte(i, mfactor=2)) # double
+ tl.append(pb)
+ m.d.comb += pbs.eq(Cat(*tl))
+
+ # negated-temporary copy of partition bits
+ npbs = Signal.like(pbs, reset_less=True)
+ m.d.comb += npbs.eq(~pbs)
+ byte_count = 8 // len(parts)
+ for i in range(len(parts)):
+ pbl = []
+ pbl.append(npbs[i * byte_count - 1])
+ for j in range(i * byte_count, (i + 1) * byte_count - 1):
+ pbl.append(pbs[j])
+ pbl.append(npbs[(i + 1) * byte_count - 1])
+ value = Signal(len(pbl), name="value_%d" % i, reset_less=True)
+ m.d.comb += value.eq(Cat(*pbl))
+ m.d.comb += parts[i].eq(~(value).bool())
+
+ return m
+
+
class Part(Elaboratable):
""" a key class which, depending on the partitioning, will determine
what action to take when parts of the output are signed or unsigned.
the extra terms - as separate terms - are then thrown at the
AddReduce alongside the multiplication part-results.
"""
- def __init__(self, width, n_parts, n_levels, pbwid):
+ def __init__(self, epps, width, n_parts, n_levels, pbwid):
+
+ self.pbwid = pbwid
+ self.epps = epps
# inputs
self.a = Signal(64)
# outputs
self.parts = [Signal(name=f"part_{i}") for i in range(n_parts)]
- self.delayed_parts = [
- [Signal(name=f"delayed_part_{delay}_{i}")
- for i in range(n_parts)]
- for delay in range(n_levels)]
- # XXX REALLY WEIRD BUG - have to take a copy of the last delayed_parts
- self.dplast = [Signal(name=f"dplast_{i}")
- for i in range(n_parts)]
self.not_a_term = Signal(width)
self.neg_lsb_a_term = Signal(width)
def elaborate(self, platform):
m = Module()
- pbs, parts, delayed_parts = self.pbs, self.parts, self.delayed_parts
- # negated-temporary copy of partition bits
- npbs = Signal.like(pbs, reset_less=True)
- m.d.comb += npbs.eq(~pbs)
+ pbs, parts = self.pbs, self.parts
+ epps = self.epps
+ m.submodules.p = p = Parts(self.pbwid, epps, len(parts))
+ m.d.comb += p.epps.eq(epps)
+ parts = p.parts
+
byte_count = 8 // len(parts)
- for i in range(len(parts)):
- pbl = []
- pbl.append(npbs[i * byte_count - 1])
- for j in range(i * byte_count, (i + 1) * byte_count - 1):
- pbl.append(pbs[j])
- pbl.append(npbs[(i + 1) * byte_count - 1])
- value = Signal(len(pbl), name="value_%di" % i, reset_less=True)
- m.d.comb += value.eq(Cat(*pbl))
- m.d.comb += parts[i].eq(~(value).bool())
- m.d.comb += delayed_parts[0][i].eq(parts[i])
- m.d.sync += [delayed_parts[j + 1][i].eq(delayed_parts[j][i])
- for j in range(len(delayed_parts)-1)]
- m.d.comb += self.dplast[i].eq(delayed_parts[-1][i])
- not_a_term, neg_lsb_a_term, not_b_term, neg_lsb_b_term = \
- self.not_a_term, self.neg_lsb_a_term, \
- self.not_b_term, self.neg_lsb_b_term
+ not_a_term, neg_lsb_a_term, not_b_term, neg_lsb_b_term = (
+ self.not_a_term, self.neg_lsb_a_term,
+ self.not_b_term, self.neg_lsb_b_term)
byte_width = 8 // len(parts) # byte width
bit_wid = 8 * byte_width # bit width
# output
self.output = Signal(64)
- def _part_byte(self, index):
- if index == -1 or index == 7:
- return C(True, 1)
- assert index >= 0 and index < 8
- return self.part_pts[index * 8 + 8]
-
def elaborate(self, platform):
m = Module()
tl = []
for i in range(8):
pb = Signal(name="pb%d" % i, reset_less=True)
- m.d.comb += pb.eq(self._part_byte(i))
+ m.d.comb += pb.eq(self.part_pts.part_byte(i))
tl.append(pb)
m.d.comb += pbs.eq(Cat(*tl))
+ # create (doubled) PartitionPoints (output is double input width)
+ expanded_part_pts = eps = PartitionPoints()
+ for i, v in self.part_pts.items():
+ ep = Signal(name=f"expanded_part_pts_{i*2}", reset_less=True)
+ expanded_part_pts[i * 2] = ep
+ m.d.comb += ep.eq(v)
+
# local variables
signs = []
for i in range(8):
m.d.comb += s.part_ops.eq(self.part_ops[i])
n_levels = len(self.register_levels)+1
- m.submodules.part_8 = part_8 = Part(128, 8, n_levels, 8)
- m.submodules.part_16 = part_16 = Part(128, 4, n_levels, 8)
- m.submodules.part_32 = part_32 = Part(128, 2, n_levels, 8)
- m.submodules.part_64 = part_64 = Part(128, 1, n_levels, 8)
+ m.submodules.part_8 = part_8 = Part(eps, 128, 8, n_levels, 8)
+ m.submodules.part_16 = part_16 = Part(eps, 128, 4, n_levels, 8)
+ m.submodules.part_32 = part_32 = Part(eps, 128, 2, n_levels, 8)
+ m.submodules.part_64 = part_64 = Part(eps, 128, 1, n_levels, 8)
nat_l, nbt_l, nla_l, nlb_l = [], [], [], []
for mod in [part_8, part_16, part_32, part_64]:
m.d.comb += mod.a.eq(self.a)
m.d.comb += mod.orin[i].eq(l[i])
terms.append(mod.orout)
- expanded_part_pts = PartitionPoints()
- for i, v in self.part_pts.items():
- signal = Signal(name=f"expanded_part_pts_{i*2}", reset_less=True)
- expanded_part_pts[i * 2] = signal
- m.d.comb += signal.eq(v)
-
add_reduce = AddReduce(terms,
128,
self.register_levels,
expanded_part_pts,
self.part_ops)
- out_part_ops = add_reduce.levels[-1].out_part_ops
+ out_part_ops = add_reduce.o.part_ops
+ out_part_pts = add_reduce.o.reg_partition_points
m.submodules.add_reduce = add_reduce
- m.d.comb += self._intermediate_output.eq(add_reduce.output)
+ m.d.comb += self._intermediate_output.eq(add_reduce.o.output)
# create _output_64
m.submodules.io64 = io64 = IntermediateOut(64, 128, 1)
m.d.comb += io64.intermed.eq(self._intermediate_output)
for i in range(8):
m.d.comb += io8.part_ops[i].eq(out_part_ops[i])
+ m.submodules.p_8 = p_8 = Parts(8, eps, len(part_8.parts))
+ m.submodules.p_16 = p_16 = Parts(8, eps, len(part_16.parts))
+ m.submodules.p_32 = p_32 = Parts(8, eps, len(part_32.parts))
+ m.submodules.p_64 = p_64 = Parts(8, eps, len(part_64.parts))
+
+ m.d.comb += p_8.epps.eq(out_part_pts)
+ m.d.comb += p_16.epps.eq(out_part_pts)
+ m.d.comb += p_32.epps.eq(out_part_pts)
+ m.d.comb += p_64.epps.eq(out_part_pts)
+
# final output
m.submodules.finalout = finalout = FinalOut(64)
- for i in range(len(part_8.delayed_parts[-1])):
- m.d.comb += finalout.d8[i].eq(part_8.dplast[i])
- for i in range(len(part_16.delayed_parts[-1])):
- m.d.comb += finalout.d16[i].eq(part_16.dplast[i])
- for i in range(len(part_32.delayed_parts[-1])):
- m.d.comb += finalout.d32[i].eq(part_32.dplast[i])
+ for i in range(len(part_8.parts)):
+ m.d.comb += finalout.d8[i].eq(p_8.parts[i])
+ for i in range(len(part_16.parts)):
+ m.d.comb += finalout.d16[i].eq(p_16.parts[i])
+ for i in range(len(part_32.parts)):
+ m.d.comb += finalout.d32[i].eq(p_32.parts[i])
m.d.comb += finalout.i8.eq(io8.output)
m.d.comb += finalout.i16.eq(io16.output)
m.d.comb += finalout.i32.eq(io32.output)
projects / ieee754fpu.git / blobdiff