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tinygrad/tinygrad/codegen/kernel.py
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2024-07-21 13:28:53 -03:00

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Python

from __future__ import annotations
import itertools, functools
from dataclasses import replace
from collections import defaultdict
from typing import Optional, List, Tuple, cast, Dict, Union, Final, DefaultDict
from tinygrad.ops import LazyOp, UnaryOps, BinaryOps, ReduceOps, MemBuffer, ConstBuffer, BufferOps, MetaOps, UNSAFE_PAD_OPS, verify_lazyop, KernelInfo
from tinygrad.device import Device
from tinygrad.renderer import Renderer, TensorCore, Program
from tinygrad.dtype import ImageDType
from tinygrad.helpers import all_same, colored, ansilen, dedup, getenv, prod, DEBUG, TC_OPT, USE_TC, round_up, all_int, \
get_contraction, to_function_name, diskcache_put, ContextVar
from tinygrad.shape.shapetracker import ShapeTracker
from tinygrad.shape.symbolic import sint
from tinygrad.shape.view import strides_for_shape
from tinygrad.codegen.uops import UOps, flops_mem
from tinygrad.codegen.uopgraph import UOpGraph
from tinygrad.codegen.lowerer import lazyop_to_uop
from dataclasses import dataclass
from enum import Enum, auto
class OptOps(Enum):
TC = auto(); UPCAST = auto(); UPCASTMID = auto(); UNROLL = auto(); LOCAL = auto() # noqa: E702
GROUP = auto(); GROUPTOP = auto(); NOLOCALS = auto(); PADTO = auto(); MERGE = auto(); SWAP = auto() # noqa: E702
def __lt__(self, x:OptOps): return self.value < x.value
class KernelOptError(Exception): pass
def check(cond:bool, msg:str=""):
if not cond: raise KernelOptError(msg)
@dataclass(frozen=True, order=True)
class Opt:
op: OptOps
axis: Optional[int] = None
amt: Optional[int] = None
def __repr__(self): return f"Opt(op={self.op}, axis={self.axis}, amt={self.amt})"
def real_axis(self, k:Kernel):
if self.axis is None: return -1
if self.op is OptOps.UNROLL: return k.first_reduce+self.axis
if self.op in {OptOps.GROUP, OptOps.GROUPTOP}: return k.first_reduce+k.group_for_reduces+self.axis
return self.axis
@dataclass
class TensorCoreOptions:
axes: Tuple[int, ...] # the location of the original N and M axes if still in the shape
axes_exist: Tuple[bool, ...] # true if the original N and M axes are still in the shape
axis_pads: Tuple[Tuple[int, int], ...]
def fix_axes(self, removed_axis:int): # adjust the TC axes if necesssary when a dimension is removed
axes, axes_exist = list(self.axes), list(self.axes_exist)
for tc_dim in [i for i in range(2) if axes_exist[i]]:
if removed_axis < axes[tc_dim]: axes[tc_dim] -= 1
elif removed_axis == axes[tc_dim]: axes_exist[tc_dim] = False
self.axes, self.axes_exist = tuple(axes), tuple(axes_exist)
class Kernel:
def __init__(self, *ast:LazyOp, opts:Optional[Renderer]=None):
if len(ast) > 1 or ast[0].op is BufferOps.STORE:
assert all(x.op is BufferOps.STORE for x in ast)
self.ast = LazyOp(MetaOps.KERNEL, ast)
else:
assert len(ast) == 1 and ast[0].op is MetaOps.KERNEL
self.ast = ast[0]
self.opts = opts if opts is not None else Device[Device.DEFAULT].renderer
try: lazyop_sts_map = verify_lazyop(self.ast)
except AssertionError as e:
print("INVALID AST")
for op in ast: print(op)
raise e
cached_ordered_lazyops: Dict[LazyOp, List[LazyOp]] = {}
def ordered_lazyops(op):
if op not in cached_ordered_lazyops: cached_ordered_lazyops[op] = dedup([item for x in op.src for item in ordered_lazyops(x)] + [op])
return cached_ordered_lazyops[op]
self.reduceops = dedup([x for x in ordered_lazyops(self.ast) if x.op in ReduceOps])
self.vars = self.ast.vars()
self.bufs: List[Union[MemBuffer, ConstBuffer]] = dedup([x.arg for x in self.ast.lazyops if x.op in BufferOps])
# get earlybufs, before any reduceops
earlybufs = [x.arg for reduceop in self.reduceops for x in reduceop.lazyops if x.op in BufferOps]
self.full_buf_index: int = self.bufs.index(earlybufs[0]) if earlybufs else 0
# NOTE: full_shape can be wrong if there's a tree of reduces
# create new shapetrackers inside this kernel, we will permute them
self.sts: List[ShapeTracker] = [x.st for x in self.bufs]
# add the shapetrackers for each reduce
# we use this to track which axes are reduced in each reduce
for x in self.reduceops:
self.sts.append(lazyop_sts_map[x])
self.sts.append(lazyop_sts_map[x.src[0]])
# move all reduce axes to the end
reduce = list(enumerate(zip(self.full_shape, self.output_shape)))
permute = tuple([i for i,(s,n) in reduce if s == n] + [i for i,(s,n) in reduce if s != n])
self.reshape_and_permute(None, permute)
# parameters for optimization
self.applied_opts: List[Opt] = []
self.group_for_reduces: int = 0
self.upcasted: int = 0
self.local_dims: int = 0
self.tensor_core: Optional[TensorCore] = None
self.tensor_core_opts: Optional[TensorCoreOptions] = None
# the local aliased buffers for A and B
self.bufs_for_tensor_core: Dict[LazyOp, Tuple[int, int]] = {}
self.dont_use_locals: bool = False
# group simplifies
self.simplify_ones()
self.simplify_merge_adjacent()
# cache
self.applied_opts_cache: Optional[List[Opt]] = None
def copy(self):
ret = type(self).__new__(type(self))
# base linearizer params
ret.opts, ret.ast = self.opts, self.ast
# things downstream of the AST
ret.reduceops, ret.vars, ret.bufs, ret.full_buf_index = \
self.reduceops, self.vars, self.bufs, self.full_buf_index
ret.sts = self.sts[:len(ret.bufs)+len(ret.reduceops)*2] # NOTE: must redo the local buffers with TC in beam
# parameters for optimizations
ret.applied_opts, ret.group_for_reduces, ret.upcasted, ret.local_dims, ret.dont_use_locals = \
self.applied_opts[:], self.group_for_reduces, self.upcasted, self.local_dims, self.dont_use_locals
ret.tensor_core, ret.tensor_core_opts, ret.bufs_for_tensor_core = self.tensor_core, self.tensor_core_opts, self.bufs_for_tensor_core
# uncached since linearize didn't run
ret.applied_opts_cache = None
return ret
@property
def membufs(self) -> List[MemBuffer]: return [x for x in self.bufs if isinstance(x, MemBuffer)]
# TODO: these need more tests or it might silently be no-op
def float4_axis(self, i:int): return [x-(self.shape_len-self.upcasted) for x in self.sts[i].unit_stride_axes() if x >= self.shape_len-self.upcasted and self.sts[i].shape[x]%4 == 0] # noqa: E501
def upcasted_axis(self, i:int) -> List[Tuple[int, Optional[sint], bool]]:
upcasted_shape, upcasted_stride = self.sts[i].shape[self.shape_len-self.upcasted:], self.sts[i].real_strides()[self.shape_len-self.upcasted:]
assert all_int(upcasted_shape), f"cannot upcast a symbolic amount {upcasted_shape=}"
return list(zip(upcasted_shape, upcasted_stride,
[x!=y for x,y in zip(self.sts[0].shape[self.shape_len-self.upcasted:], self.full_shape[self.shape_len-self.upcasted:])]))
@property
def first_reduce(self) -> int:
return [x!=y for x,y in zip(self.sts[0].shape[:self.shape_len-self.upcasted]+(0,), self.full_shape[:self.shape_len-self.upcasted]+(1,))].index(True) # noqa: E501
@property
def reduceop(self) -> Optional[LazyOp]: return self.reduceops[0] if len(self.reduceops) > 0 else None
@property
def output_shape(self) -> Tuple[sint, ...]: return self.sts[0].shape
@property
def full_shape(self) -> Tuple[sint, ...]: return self.sts[self.full_buf_index].shape
@property
def full_unupcasted_shape(self) -> Tuple[sint, ...]: return self.full_shape[:self.shape_len-self.upcasted]
@property
def shape_len(self) -> int: return len(self.sts[0].shape)
@property
def upcast_in_mid_reduce_axes(self) -> List[int]:
return [j for j in range(self.first_reduce, self.first_reduce+self.group_for_reduces) if self.full_shape[j] == self.sts[0].shape[j]]
@property
def global_dims(self) -> int: return self.first_reduce-self.local_dims
# there's eight chunks of the shape
# blue -- global dims
# cyan -- local dims (warp ones first)
# *** self.first_reduce
# green -- reduce-local dims
# white -- reduce-late upcasted dim (self.upcast_in_mid_reduce_axes)
# red -- reduce loops
# *** self.upcasted
# purple -- reduce upcasted
# yellow -- normal upcasted dimensions
def colors(self) -> List[str]:
# first non local non reduce dims are global (blue)
colors = ["blue"] * self.global_dims if not self.dont_use_locals else ["BLUE"] * self.global_dims
# after global are local_dims; warp ones used in tensor cores must be closest to first_reduce (cyan)
colors += ["cyan"] * self.local_dims
# between first_reduce and first_reduce + group_for_reduces, they are either upcast mid reduce (white), or late upcasted (green)
colors += ["white" if i in self.upcast_in_mid_reduce_axes else "green" for i in range(self.first_reduce, self.first_reduce + self.group_for_reduces)] # noqa: E501
# between first_reduce + group_for_reduces and upcasted, they are reduce (red)
colors += ["red"] * ((self.shape_len-self.upcasted) - (self.first_reduce + self.group_for_reduces))
# upcasted dimensions are reduce (magenta) or normal (yellow)
colors += ["magenta" if self.full_shape[i] != self.sts[0].shape[i] else "yellow" for i in range(self.shape_len-self.upcasted, self.shape_len)]
assert len(colors) == self.shape_len, "colors size mismatch"
return colors
def colored_shape(self, pad:Optional[int]=None, dense=False) -> str:
ret = ' '.join(colored(s, color) for s,color in zip([f"{s:4d}" if isinstance(s, int) and not dense else s for s in self.full_shape], self.colors())) # noqa: E501
if pad: ret += ' '*(pad-ansilen(ret))
return ret
# ******************** base simplifiers ********************
# apply reshape and permute to all shapetrackers
def reshape_and_permute(self, new_shape_fxn, axis):
new_sts = []
for st in self.sts:
if new_shape_fxn is not None: st = st.reshape(tuple(new_shape_fxn(st.shape)))
if axis is not None: st = st.permute(tuple(axis))
new_sts.append(st)
self.sts = new_sts
# drops the final dimension
def upcast(self):
check(self.full_shape[-1] != 1, "can't upcast a dimension with size 1")
self.upcasted += 1
# axis : the axis to pull from
# amount : the amount to take
# top : if you want to pull that amount from the top
# insert_before : place to insert the new stuff
def shift_to(self, axis, amount, top=False, insert_before=None):
if insert_before is None: insert_before = self.shape_len
move_axis = axis if top else axis+1
if move_axis < insert_before: insert_before += 1
self.reshape_and_permute(
lambda x: x[0:axis] + (((amount, x[axis]//amount) if top else (x[axis]//amount, amount)) if x[axis] > 1 else (1,1)) + x[axis+1:],
[i for i in range(insert_before) if i != move_axis] + [move_axis] + [i for i in range(insert_before, self.shape_len+1) if i != move_axis])
# ******************** complex simplifiers ********************
def simplify_ones(self) -> bool:
# remove places where the shape is all ones
# TODO: this should be factored in to multi shape stride
if self.shape_len == 0: return False
all_ones = [s==1 for s in self.full_shape]
self.local_dims -= sum(all_ones[self.first_reduce-self.local_dims:self.first_reduce])
self.upcasted -= sum(all_ones[self.shape_len-self.upcasted:]) # TODO: no necessary since upcasted axis can't be un-upcasted
self.reshape_and_permute(lambda shape: [x for i,x in enumerate(shape) if not all_ones[i]], None)
return any(all_ones)
def simplify_merge_adjacent(self):
if self.shape_len == 0: return
shapes, strides = [x.shape for x in self.sts], [x.real_strides() for x in self.sts]
# if it's an image, insert fake strides such that this fusion doesn't happen across image axes
if isinstance(self.bufs[0].dtype, ImageDType):
base_shape = self.bufs[0].dtype.shape
if shape_idx_groups := get_contraction(self.output_shape, base_shape):
special_strides: Tuple[sint, ...] = tuple()
for i,g in enumerate(shape_idx_groups):
shape_piece = tuple(self.output_shape[x] for x in g)
assert prod(shape_piece) == base_shape[i], f"get_contraction was wrong? {shape_piece} != {base_shape[i]}"
special_strides += strides_for_shape(shape_piece)
# adding the fake image shape
shapes.append(self.output_shape)
strides.append(special_strides)
# merge dimensions if we can, multi _merge_dims
# NOTE: this does not always preserve the reduce dimension
# TODO: move this into shapetracker, with tests!
# TODO: how does this work with multi-reduce?
rets = [[(s[0], st[0])] for s,st in zip(shapes, strides)]
for i in range(1, len(shapes[0])):
can_merge = []
for s,st,ret in zip(shapes, strides, rets):
# TODO: added the always mergeability of 1s, is this right? if so, add to shapetracker in the 1 case
si, sti, last_st = s[i], st[i], ret[-1][1]
can_merge.append((sti is not None) and ((sti != 0 and last_st == si*sti) or (sti == 0 and last_st == 0)))
# more can merge than this
mergeable = all(can_merge) and i != self.first_reduce
for j,(s,st) in enumerate(zip(shapes, strides)):
if mergeable: rets[j][-1] = (rets[j][-1][0] * s[i], st[i])
else: rets[j].append((s[i], st[i]))
# do the reshapes
for i,x in enumerate(rets[:len(self.sts)]): self.sts[i] = self.sts[i].reshape(tuple([y[0] for y in x]))
# ******************** high level optimizers ********************
def _create_tc_opts(self, reduceop:LazyOp, tc:TensorCore, axis:int, opt_level:int) -> Optional[TensorCoreOptions]:
has_cast = tc.dtype_in != tc.dtype_out
if has_cast and not(reduceop.src[0].op is UnaryOps.CAST and reduceop.src[0].arg == tc.dtype_out): return None
mul_op = reduceop.src[0].src[0] if has_cast else reduceop.src[0]
if mul_op.op is not BinaryOps.MUL: return None
def buf_index(src: LazyOp) -> Optional[int]:
# TODO: apply tc even if the sources are not from LOAD
if src.op is BufferOps.LOAD and src.arg.dtype == tc.dtype_in: return self.bufs.index(cast(MemBuffer, src.arg))
try:
if opt_level >= 1 and src.op is UnaryOps.CAST and src.arg == tc.dtype_in: return self.bufs.index(cast(MemBuffer, src.src[0].arg))
except ValueError: return None
return None
if (buf0:=buf_index(mul_op.src[0])) is None or (buf1:=buf_index(mul_op.src[1])) is None: return None
buf0_strides, buf1_strides = self.sts[buf0].real_strides(), self.sts[buf1].real_strides()
axis_buf0 = [(i,self.full_shape[i],buf1_strides[i]) for i,s in enumerate(buf0_strides[:self.first_reduce]) if s == 0]
axis_buf1 = [(i,self.full_shape[i],buf0_strides[i]) for i,s in enumerate(buf1_strides[:self.first_reduce]) if s == 0]
if not(axis_buf0 and axis_buf1 and ((self.shape_len-self.first_reduce) == 1 or (opt_level >= 1))): return None
axis_choices = list(itertools.product(axis_buf0, axis_buf1, range(self.first_reduce, self.shape_len)))
if not(axis < len(axis_choices)): return None
s0, s1, s2 = axis_choices[-(axis+1)][0][0], axis_choices[-(axis+1)][1][0], axis_choices[-(axis+1)][2] # s0 is n, s1 is m, s2 is k
axis_pads = tuple((x, tc.dims[i]) for i, x in enumerate([s0, s1, s2]) if self.full_shape[x]%tc.dims[i] != 0)
if axis_pads and (opt_level < 2): return None
self.bufs_for_tensor_core[reduceop] = (buf0, buf1)
if DEBUG >= 3: print("TENSOR CORES", axis_buf0, axis_buf1, tc)
return TensorCoreOptions(axes=(s0, s1, s2), axes_exist=(True, True), axis_pads=axis_pads)
def _apply_tc_opt(self, use_tensor_cores:int, axis:int, opt_level:int) -> bool:
if use_tensor_cores and (self.opts.has_local or getenv("AMX",0)) and self.reduceop is not None and self.reduceop.op is ReduceOps.SUM:
for tc in self.opts.tensor_cores:
tensor_core_opts = [self._create_tc_opts(reduceop, tc, axis, opt_level) for reduceop in self.reduceops]
# can only fuse reduces with the same tc options
assert all_same(tensor_core_opts)
if tensor_core_opts[0] is None: continue
# tensor core -- unroll the reduce dim, upcast input, then create the correct thread pattern
self.tensor_core_opts = tc_opts = tensor_core_opts[0]
# attempt to pad the tensor axes that require it
try:
for axis, dim in tc_opts.axis_pads: self.apply_opt(Opt(OptOps.PADTO, axis, dim), append_opt=False) # PADTO might fail
except KernelOptError: continue
if self.opts.device == "AMD":
# NOTE: AMD requires locals first
self.apply_opt(Opt(OptOps.UNROLL, tc_opts.axes[2]-self.first_reduce, tc.dims[2]), append_opt=False)
for (tc_dim, tc_amt) in tc.threads:
self.apply_opt(Opt(OptOps.LOCAL, tc_opts.axes[tc_dim], tc_amt), append_opt=False)
for i, sz in enumerate([prod(x) for x in [[x[1] for x in tc.threads if x[0]==dim] for dim in range(2)]]): # upcast non-local'd N, M
if tc.dims[i] > sz: self.apply_opt(Opt(OptOps.UPCAST, tc_opts.axes[i], tc.dims[i]//sz), append_opt=False)
elif self.opts.device == "METAL":
self.apply_opt(Opt(OptOps.UNROLL, tc_opts.axes[2]-self.first_reduce, tc.dims[2]), append_opt=False)
for i, sz in enumerate([prod(x) for x in [[x[1] for x in tc.threads if x[0]==dim] for dim in range(2)]]): # upcast non-local'd N, M
if tc.dims[i] > sz: self.apply_opt(Opt(OptOps.UPCAST, tc_opts.axes[i], tc.dims[i]//sz), append_opt=False)
for (tc_dim, tc_amt) in tc.threads:
self.apply_opt(Opt(OptOps.LOCAL, tc_opts.axes[tc_dim], tc_amt), append_opt=False)
elif self.opts.device == "CLANG":
for (tc_dim, tc_amt) in tc.threads:
self.apply_opt(Opt(OptOps.UPCAST, tc_opts.axes[tc_dim], tc_amt), append_opt=False)
elif self.opts.device in {"CUDA", "NV"}:
self.apply_opt(Opt(OptOps.UNROLL, tc_opts.axes[2]-self.first_reduce, 8), append_opt=False)
self.apply_opt(Opt(OptOps.UNROLL, tc_opts.axes[2]-self.first_reduce, 2), append_opt=False)
self.apply_opt(Opt(OptOps.UPCAST, tc_opts.axes[0], 2), append_opt=False)
self.apply_opt(Opt(OptOps.LOCAL, tc_opts.axes[0], 2), append_opt=False)
self.apply_opt(Opt(OptOps.LOCAL, tc_opts.axes[0], 2), append_opt=False)
self.apply_opt(Opt(OptOps.LOCAL, tc_opts.axes[1], 2), append_opt=False)
self.apply_opt(Opt(OptOps.LOCAL, tc_opts.axes[1], 2), append_opt=False)
self.apply_opt(Opt(OptOps.LOCAL, tc_opts.axes[1], 2), append_opt=False)
self.apply_opt(Opt(OptOps.UPCAST, tc_opts.axes[1], 2), append_opt=False)
# NOTE: MERGE is needed because we can't deal with two upcasted dimensions
self.apply_opt(Opt(OptOps.MERGE, self.shape_len-2), append_opt=False)
# assert tensor core
if use_tensor_cores == 1: self.tensor_core = tc # TC=2 will do the shape ops without the WMMA
return True
return False
def apply_tensor_cores(self, use_tensor_cores=1, extra_opts:Optional[List[Opt]]=None, axis:int=0, tc_opt:Optional[int]=None) -> bool:
""" Attempts to apply a tensor core optimization to the kernel. If one exists and applies properly, return true, otherwise return false.
Tensor cores are optimized instructions that matrix multiply-accumulate across a wave of threads: D(M, N) = A(M, K) * B(K, N) + C(M, N).
Keyword arguments:
use_tensor_cores -- controls how tensor cores are applied (default 1)
0: will disable any tensor core matching
1: enable tensor cores
2: apply tensor core shape but don't use UOp.WMMA
extra_opts -- additional Opt's to apply after the tensor core instead of the hand-coded additional Opt's (default None)
tc_opt -- controls which kinds of kernels may be eligible for tensor cores application (default 2 during BEAM, 0 otherwise)
0: applies to only kernels with a single reduce axis and direct BufferOps.LOAD into BinaryOps.MUL
1: allows kernels with multiple reduce axes and also multiplication of UnaryOps.CAST'd buffers
2: allows kernels with M, N, K axes that are not multiples of the tensor core dimensions by applying padding those axes as needed
"""
if tc_opt is None: tc_opt = TC_OPT.value
if not self.opts.tensor_cores and use_tensor_cores != 2: return False
try: # check TC first and apply hand-coded opts if successful
self.apply_opt(Opt(OptOps.TC, axis, tc_opt))
if (tc_opts:=self.tensor_core_opts) is not None and not getenv("AMX", 0):
if extra_opts is not None:
for opt in extra_opts: self.apply_opt(opt)
else:
# hand-coded TC opts
def late_upcast_tc(tc_dim: int):
if tc_opts.axes_exist[tc_dim]:
ax_div = [upc for upc in [5,4,3,2,1] if self.full_shape[tc_opts.axes[tc_dim]]%upc == 0][0]
if ax_div != 1: self.apply_opt(Opt(OptOps.UPCAST, tc_opts.axes[tc_dim], ax_div))
late_upcast_tc(1) # attempt to upcast M
late_upcast_tc(0) # attempt to upcast N
if self.tensor_core and tc_opts.axes_exist[0]: # attempt to local N
for upc in [4,2]:
if self.full_shape[tc_opts.axes[0]] % upc == 0:
self.apply_opt(Opt(OptOps.LOCAL, tc_opts.axes[0], upc))
break
return True
except KernelOptError:
return False
def apply_opt(self, opt:Opt, append_opt:bool=True):
check(not self.dont_use_locals or opt.op not in {OptOps.LOCAL, OptOps.GROUP, OptOps.GROUPTOP, OptOps.UPCASTMID}, "not using locals")
if opt.op is OptOps.TC:
check(len(self.applied_opts) == 0, "tensor core opts must be first") # TODO: things like PADTO might be fine
check(opt.axis is not None and opt.amt is not None, "tensor core opts must have an axis and amt")
check((use_tensor_cores:=USE_TC.value) == 2 or len(self.opts.tensor_cores) > 0, "must have tensor cores or TC=2")
check(self._apply_tc_opt(use_tensor_cores, cast(int, opt.axis), cast(int, opt.amt)), "no tensor core available")
self.applied_opts.append(opt)
return
axis = opt.real_axis(self)
check(axis < len(self.full_shape), "invalid axis")
if opt.op is OptOps.SWAP: amt = cast(int, opt.amt) # amt is an axis in the SWAPs
elif opt.amt is not None:
amt = opt.amt if opt.amt != 0 else self.full_shape[axis]
check(isinstance(amt, int) and amt != 1, "shift/padto of amt 1 or Node is meaningless")
if opt.op is not OptOps.PADTO: check(self.full_shape[axis] % amt == 0, "no longer valid shift")
else: amt = -1
if self.reduceop and (opt.op in {OptOps.GROUP, OptOps.GROUPTOP} or (self.group_for_reduces and opt.op not in {OptOps.NOLOCALS, OptOps.PADTO})):
acc_sz, upcast_idx = dt.base.itemsize if isinstance((dt:=self.reduceop.dtype), ImageDType) else dt.itemsize, self.shape_len-self.upcasted
upcast_sz = prod([a for a,b in zip(self.full_shape[upcast_idx:], self.sts[0].shape[upcast_idx:]) if a == b])
local_sz = prod(self.full_shape[self.first_reduce-self.local_dims:self.first_reduce+self.group_for_reduces])
smem_sz = amt*acc_sz*upcast_sz*local_sz
check(smem_sz <= self.opts.shared_max, f"exceeds maximum shared memory size: needs {smem_sz}, max {self.opts.shared_max}")
if opt.op is OptOps.LOCAL: # cyan
check(self.opts.has_local, "target does not support local")
check(axis < self.global_dims, "local is for globals")
self.shift_to(axis, amt, insert_before=self.first_reduce)
self.local_dims += 1
elif opt.op in {OptOps.GROUP, OptOps.GROUPTOP}: # green
check(self.opts.has_local and self.opts.has_shared, "target does not support local or shared mem")
check(axis >= self.first_reduce + self.group_for_reduces and axis < self.shape_len-self.upcasted, "must be reduce axis to group")
check(not self.tensor_core, "can't group with tensor cores")
check(len(self.reduceops) == 1, "can't group with multiple reduces")
self.shift_to(axis, amt, top=(opt.op is OptOps.GROUPTOP), insert_before=self.first_reduce + self.group_for_reduces)
self.group_for_reduces += 1
elif opt.op is OptOps.UNROLL: # purple
check(axis < self.shape_len-self.upcasted, "can't upcasted already upcasted")
check(amt <= 32, "don't unroll more than 32")
# TODO: fix upcast_count to put purples before yellows. broken because of METAL tensor cores
#upcast_count = sum(x == y for x,y in zip(self.full_shape[-self.upcasted:], self.output_shape[-self.upcasted:])) if self.upcasted else 0
#self.shift_to(axis, amt, insert_before=None if upcast_count == 0 else self.shape_len-upcast_count)
if self.full_shape[axis] == amt and axis == self.first_reduce: self.local_dims += 1 # first_reduce will ++, so offset loss in simplify_ones
if self.full_shape[axis] == amt and axis < self.first_reduce+self.group_for_reduces: self.group_for_reduces -= 1 # fully unrolling a GROUP
self.shift_to(axis, amt, insert_before=None)
self.upcast()
elif opt.op is OptOps.UPCAST: # yellow
check(axis < self.first_reduce, "upcast is for non-reduce")
check(not(self.tensor_core and self.global_dims <= axis < self.global_dims+len(self.tensor_core.threads)), "can't upcast TC locals")
check(amt <= 8, "don't upcast more than 8")
self.shift_to(axis, amt, insert_before=None)
self.upcast()
elif opt.op is OptOps.UPCASTMID: # white
check(self.bufs[0].dtype.name.startswith('image') and not self.float4_axis(0) and self.group_for_reduces != 0 and self.first_reduce <= 2 and prod(self.sts[0].shape) > 1, "invalid upcast mid reduce") # noqa: E501
axes = self.sts[0].unit_stride_axes()
check(len(axes) == 1, f"wrong number of stride 1 axis : {axes}")
check(axes[0] == axis, "wrong axis")
check(amt == 4, "don't upcast mid anything but 4")
self.shift_to(axis, amt, insert_before=self.first_reduce + self.group_for_reduces)
self.group_for_reduces += 1
elif opt.op is OptOps.NOLOCALS:
check(self.opts.has_local and not self.dont_use_locals, "NOLOCALS is meaningless if target does not support local or already not using locals")
check(self.local_dims == 0 and self.group_for_reduces == 0, "can't have no locals with locals")
self.dont_use_locals = True
elif opt.op is OptOps.SWAP:
check(axis < amt and amt < self.global_dims, f"swap is only for globals with axis < amt, getting {amt=}, {axis=}, {self.global_dims=}")
permute = list(range(self.shape_len))
permute[axis], permute[amt] = permute[amt], permute[axis]
self.reshape_and_permute(None, tuple(permute))
elif opt.op is OptOps.MERGE:
check(axis >= self.shape_len-self.upcasted, "only merge upcasted")
check(self.full_shape[axis:axis+2] == self.output_shape[axis:axis+2], "can't merge reduces")
self.reshape_and_permute(None, tuple(range(axis)) + (axis+1, axis) + tuple(range(axis+2, self.shape_len)))
self.reshape_and_permute(lambda x: x[0:axis] + (x[axis] * x[axis+1],) + x[axis+2:], None)
self.upcasted -= 1
elif opt.op is OptOps.PADTO:
check(not self.vars, "does not work with symbolic shape")
check(axis < self.shape_len - self.upcasted, "cannot pad upcasted")
# ok to pad SUM if all parent ops have f(0) = 0
if self.first_reduce <= axis:
check((r:=cast(LazyOp, self.reduceop)).op is ReduceOps.SUM and \
all(op.op not in UNSAFE_PAD_OPS for sop in r.src for op in sop.lazyops), "cannot pad")
padded = False
for i,st in enumerate(self.sts):
if self.sts[i].shape[axis] == 1: continue # reduced
check(self.sts[i].shape[axis] > amt//4, f"pad adds more than quadruple the work {self.sts[i].shape[axis]=} > {amt//4=}")
if (ru := round_up(cast(int, self.sts[i].shape[axis]), amt) - self.sts[i].shape[axis]):
# pad right seems to be faster
self.sts[i] = st.pad(((0,0),) * axis + ((0,ru),) + ((0,0),) * (len(st.shape)-axis-1))
padded = True
check(padded, "nothing was padded")
if append_opt: self.applied_opts.append(opt)
if self.simplify_ones() and self.tensor_core_opts:
self.tensor_core_opts.fix_axes(axis) # fix up axes in TC opts if required after simplify_ones()
def required_optimizations(self) -> Kernel:
if self.bufs[0].dtype.__class__ is ImageDType:
unit_stride_axes_mul_4 = [i for i in self.sts[0].unit_stride_axes(ignore_valid=True) if self.sts[0].shape[i]%4 == 0]
assert len(unit_stride_axes_mul_4) >= 1, f"needs a unit stride axis in {self.bufs[0]}"
if len(unit_stride_axes_mul_4) and all(x < (self.shape_len-self.upcasted) for x in unit_stride_axes_mul_4) and unit_stride_axes_mul_4[0] not in self.upcast_in_mid_reduce_axes: # noqa: E501
self.apply_opt(Opt(OptOps.UPCAST, unit_stride_axes_mul_4[0], 4))
return self
def hand_coded_optimizations(self) -> Kernel:
self.required_optimizations()
# should use matvec - TODO: adjust/tune based on the wide vs tall/large vs small mat
MV_BLOCKSIZE, MV_THREADS_PER_ROW, MV_ROWS_PER_THREAD = getenv("MV_BLOCKSIZE", 4), getenv("MV_THREADS_PER_ROW", 8), getenv("MV_ROWS_PER_THREAD", 4)
if self.opts.has_local and getenv("MV",1) != 0 and (MV_BLOCKSIZE > 1 or MV_THREADS_PER_ROW > 1 or MV_ROWS_PER_THREAD > 1) and \
self.reduceop is not None and self.reduceop.op is ReduceOps.SUM and len(self.full_shape) >= 2 and self.opts.has_shared and \
(mulop:=self.reduceop.src[0]).op is BinaryOps.MUL and mulop.src[0].op is BufferOps.LOAD and mulop.src[1].op is BufferOps.LOAD:
st0, st1 = self.sts[self.bufs.index(mulop.src[0].arg)], self.sts[self.bufs.index(mulop.src[1].arg)]
strides0, strides1 = st0.real_strides(), st1.real_strides()
def has_expanded_axis(shape, strides): return any(s > 1 and st == 0 for s,st in zip(shape,strides))
if strides0[self.first_reduce] == 1 and not (has_expanded_axis(st0.shape, strides0) and has_expanded_axis(st1.shape, strides1)):
for global_idx in range(self.global_dims):
if self.full_shape[self.first_reduce]%MV_THREADS_PER_ROW == 0 and self.full_shape[global_idx]%(MV_BLOCKSIZE*MV_ROWS_PER_THREAD) == 0:
if DEBUG >= 3:
print(f"MATVEC: {self.full_shape=} {self.first_reduce=} {strides0=} {MV_BLOCKSIZE=} {MV_THREADS_PER_ROW=} {MV_ROWS_PER_THREAD=}")
if MV_THREADS_PER_ROW > 1: self.apply_opt(Opt(OptOps.GROUP, 0, MV_THREADS_PER_ROW))
if MV_BLOCKSIZE > 1: self.apply_opt(Opt(OptOps.LOCAL, global_idx, MV_BLOCKSIZE))
if MV_ROWS_PER_THREAD > 1: self.apply_opt(Opt(OptOps.UPCAST, global_idx, MV_ROWS_PER_THREAD))
return self
if self.opts.has_local and self.opts.has_shared and all_int(self.sts[0].shape[:self.first_reduce]):
# are we grouping? (requires local shape support)
if not self.float4_axis(0) and self.first_reduce <= 2 and self.first_reduce + 1 <= self.shape_len and prod(self.sts[0].shape[:self.first_reduce]) <= 2048: # noqa: E501
# TODO: use 1024 if it's allowed in a smarter way
for sz in ([256, 16] if prod(self.sts[0].shape[:self.first_reduce]) <= 32 else [16]):
if all(st.shape[self.first_reduce] % sz == 0 or st.shape[self.first_reduce] == 1 for st in self.sts):
try: # may fail due to excessive smem usage
self.apply_opt(Opt(OptOps.GROUPTOP, 0, sz))
break
except KernelOptError: pass
# are we upcasting in mid reduce? (only for images)
if self.bufs[0].dtype.name.startswith('image') and not self.float4_axis(0) and self.group_for_reduces and self.first_reduce <= 2 and prod(self.sts[0].shape) > 1: # noqa: E501
axes = self.sts[0].unit_stride_axes()
assert len(axes) == 1, f"wrong number of stride 1 axis : {axes}"
if self.sts[0].shape[axes[0]]%4 == 0:
self.apply_opt(Opt(OptOps.UPCASTMID, axes[0], 4))
# upcast float4 images
for buf_index,buf in enumerate(self.bufs):
unit_stride_axes_mul_4 = [i for i in self.sts[buf_index].unit_stride_axes(ignore_valid=True) if self.sts[buf_index].shape[i]%4 == 0]
if buf.dtype.__class__ is ImageDType:
#assert len(unit_stride_axes_mul_4) >= 1, f"needs a unit stride axis in {self.bufs[buf_index]}"
if len(unit_stride_axes_mul_4) and all(x < (self.shape_len-self.upcasted) for x in unit_stride_axes_mul_4) and unit_stride_axes_mul_4[0] not in self.upcast_in_mid_reduce_axes: # noqa: E501
if unit_stride_axes_mul_4[0] < self.first_reduce:
self.apply_opt(Opt(OptOps.UPCAST, unit_stride_axes_mul_4[0], 4))
else:
self.apply_opt(Opt(OptOps.UNROLL, unit_stride_axes_mul_4[0]-self.first_reduce, 4))
# no more opt if we are grouping
if self.group_for_reduces: return self
# **** below this line need to be optional and benchmarked ****
# TODO: doing extra upcasts with images doesn't work for some reason (maybe has to do with to_image_idx)
# to trigger the above bug, remove prod(self.full_shape[self.shape_len - self.upcasted:]) from the below
# expression and run test/test_ops.py with IMAGE=2
# if there are small dims with lots of valid masks, upcast them (they might be from Tensor.stack)
# this can be made much smarter
to_upcast: List[int] = []
# upcast leading axes first (hack-ish for winograd; we actually want to upcast masked axes with low stride first)
for axis in range(self.first_reduce):
# we might want to be able to split axes that are masked, or refuse to merge them in simplify_merge_adjacent
# for now skip upcasting here if there is a symbolic axis
if isinstance(self.full_shape[axis], int) and self.full_shape[axis] <= 7 and any(st.axis_is_masked(axis) for st in self.sts) and \
prod(self.full_shape[self.shape_len - self.upcasted:]) * prod(self.full_shape[j] for j in to_upcast) * self.full_shape[axis] <= 7 * 7:
if DEBUG >= 4: print(f"upcasting masked axis : {axis}")
to_upcast.append(axis)
for axis in to_upcast[::-1]: self.apply_opt(Opt(OptOps.UPCAST, axis, 0))
# potentially do more upcasts of non reduce axes based on a heuristic
upcasted_axis = set()
while prod(self.sts[0].shape[:self.first_reduce]) >= 1024:
xb_choices = []
for axis, upcast_amount in itertools.product(range(self.first_reduce), [3,4]): # consider all the non reduce axes, and a 3 or 4 reduce
# if we haven't upcasted it, it's not symbolic, it mods, and buffer has stride 0 on axis while having no stride 0 in the upcasted axis already
if axis not in upcasted_axis and isinstance(self.full_shape[axis], int) and self.full_shape[axis]%upcast_amount == 0 and any(st.views[-1].strides[axis] == 0 and not any(x[1] == 0 for x in self.upcasted_axis(buf_index)) for buf_index, st in enumerate(self.sts)): # noqa: E501
xb_choices.append((sum(st.views[-1].strides[axis]>0 for st in self.sts), sum(st.views[-1].strides[axis] for st in self.sts), axis, upcast_amount)) # noqa: E501
if xb_choices:
xb_choices = sorted(xb_choices)
if DEBUG >= 4: print(f"float4 merging axis : {xb_choices}")
self.apply_opt(Opt(OptOps.UPCAST, xb_choices[0][2], xb_choices[0][3]))
upcasted_axis.add(xb_choices[0][2])
else: break
# if last dim is small(ish) and it's a reduce dim, upcast the reduce (loop unrolling). no simplify needed since it's just an upcast.
if self.first_reduce < (self.shape_len-self.upcasted) and (prod(self.full_shape[self.shape_len-self.upcasted:]) <= 4 or not any(r for _,_,r in self.upcasted_axis(self.full_buf_index))) and (self.upcasted == 0 or prod(self.full_shape[-self.upcasted:]) < 64): # noqa: E501
if (s:=self.full_unupcasted_shape[-1]) <= 32 and isinstance(s, int): # NOTE: cannot loop unroll symbolic axis
self.apply_opt(Opt(OptOps.UNROLL, len(self.full_unupcasted_shape)-1-self.first_reduce, 0))
# if it's small, upcast a second reduce dimension too
if self.first_reduce < (self.shape_len-self.upcasted) and s <= 3 and (s2:=self.full_unupcasted_shape[-1]) <= 3 and isinstance(s2, int):
self.apply_opt(Opt(OptOps.UNROLL, len(self.full_unupcasted_shape)-1-self.first_reduce, 0))
else:
for splits in [4]:
if self.full_unupcasted_shape[-1]%splits == 0:
self.apply_opt(Opt(OptOps.UNROLL, len(self.full_unupcasted_shape)-1-self.first_reduce, splits))
break
# if nothing at all is upcasted and it's easy to, do an upcast
# TODO: this is breaking the tests
for splits in [4]:
if self.upcasted == 0 and self.full_unupcasted_shape and self.full_unupcasted_shape[-1] % splits == 0:
self.apply_opt(Opt(OptOps.UPCAST, len(self.full_unupcasted_shape)-1, splits))
# **** local groups ****
if self.opts.has_local:
if getenv("NOLOCALS") and self.local_dims == 0 and not self.group_for_reduces:
self.apply_opt(Opt(OptOps.NOLOCALS))
else:
# prioritize making expand axes local
local_axis_ranking = [(any(self.sts[buf_index].views[-1].strides[axis] == 0 for buf_index in range(len(self.sts))), axis) for axis in range(len(self.full_shape[:self.first_reduce]))] # noqa: E501
to_local: List[Tuple[int, int]] = []
for _, axis in sorted(local_axis_ranking, key=lambda x: (-x[0], -x[1])):
local_size = prod(sz for _, sz in to_local)
local_sz: Optional[int] = next((x for x in ([32] * (axis == 0) + [16, 8, 4, 3, 2]) if self.full_shape[axis] % x == 0 and local_size * x <= 128), None) # noqa: E501
if local_sz is not None: to_local.append((axis, local_sz))
deleted_shape = 0
for axis, local_sz in sorted(to_local[:3]):
axis = axis - deleted_shape
will_delete_shape = local_sz == self.full_shape[axis]
self.apply_opt(Opt(OptOps.LOCAL, axis, local_sz))
if will_delete_shape: deleted_shape += 1
return self
# **** kernel outputs ****
kernel_cnt: Final[DefaultDict[str, int]] = defaultdict(int)
@functools.cached_property
def name(self) -> str:
# kernel name (before late upcast)
name = ("r" if self.reduceop else ("C" if all(x.op in BufferOps for x in self.ast.lazyops) else "E")) + \
(f"{len(self.ast.src)}_" if len(self.ast.src) > 1 else "_") + \
colored('_', 'BLACK').join([colored(str(x), c) for x,c in zip(self.full_shape, self.colors())])
# name the function something unique
Kernel.kernel_cnt[(function_name := to_function_name(name))] += 1
suffix = f"{'n'+str(Kernel.kernel_cnt[function_name]-1)}" if Kernel.kernel_cnt[function_name] > 1 else ""
return name+colored(suffix, 'BLACK')
def get_optimized_ast(self) -> LazyOp:
# set the shapetrackers to the optimized ones, fixup reduceop
# transformed to the final LazyOp
@functools.lru_cache(None)
def fixup_ast(op:LazyOp, apply_to_st=None) -> LazyOp:
if op.op in BufferOps:
idx = self.bufs.index(op.arg)
arg = replace(op.arg, st=self.sts[idx] if apply_to_st is None else apply_to_st(self.sts[idx]))
elif op.op in ReduceOps:
reduce_idx = len(self.bufs) + self.reduceops.index(op)*2
arg = tuple(i for i in range(self.first_reduce+self.group_for_reduces, self.shape_len)
if self.sts[reduce_idx].shape[i] != self.sts[reduce_idx+1].shape[i])
if op in self.bufs_for_tensor_core and (tc := self.tensor_core):
rsrc = op.src[0]
if rsrc.op is UnaryOps.CAST: rsrc = rsrc.src[0]
assert rsrc.op is BinaryOps.MUL
def fix_st(warp_dims, tcd_dims, tcd_expand, pattern_1, pattern_2, st1):
wd = self.global_dims
tcd = self.shape_len-self.upcasted
assert st1.shape[wd:wd+len(warp_dims)] == warp_dims, f"warp dims wrong: {st1.shape[wd:wd+len(warp_dims)]=} != {warp_dims=}"
assert st1.shape[tcd:tcd+len(tcd_dims)] == tcd_dims, f"tcd dims wrong: {st1.shape[tcd:tcd+len(tcd_dims)]=} != {tcd_dims=}"
new_shape = st1.shape[:tcd] + tcd_expand + st1.shape[tcd+len(tcd_dims):] # expand the tcd
permaxis = list(range(wd))
permaxis += [y + (wd if x == 0 else tcd) for x,y in pattern_1]
permaxis += list(range(wd+len(warp_dims), tcd))
permaxis += [y + (wd if x == 0 else tcd) for x,y in pattern_2]
permaxis += list(range(tcd+len(tcd_expand), len(new_shape)))
return st1.reshape(new_shape).simplify().permute(tuple(permaxis)).reshape(st1.shape).simplify()
if self.opts.device == "AMD":
reduce_axes = [self.shape_len-self.upcasted]
upcast_axis = (self.shape_len-self.upcasted, self.shape_len-self.upcasted, self.shape_len-self.upcasted+1)
fix_st1 = functools.partial(fix_st, (8,2,2), (16,8), (16,2,4), ((1,2), (0,2), (1,1), (0,1)), ((1,0), (0,0)))
fix_st2 = None
elif self.opts.device == "METAL":
reduce_axes = [self.shape_len-self.upcasted]
upcast_axis = (self.shape_len-self.upcasted+1, self.shape_len-self.upcasted+1, self.shape_len-self.upcasted+1)
fix_st1 = functools.partial(fix_st, (2,4,2,2), (8,2), (2,2,2,2), ((1,1), (0,1), (1,0), (0,3)), ((0,0), (0,2), (1,3), (1,2)))
fix_st2 = functools.partial(fix_st, (2,4,2,2), (8,2), (2,2,2,2), ((0,0), (1,1), (1,2), (0,2), (1,0)), ((0,1), (0,3), (1,3)))
elif self.opts.device == "CLANG":
reduce_axes, fix_st1, fix_st2 = [], None, None
upcast_axis = (self.shape_len-self.upcasted+1, self.shape_len-self.upcasted, self.shape_len-self.upcasted+1)
elif self.opts.device in {"CUDA", "NV"}:
reduce_axes = [self.shape_len-self.upcasted, self.shape_len-self.upcasted+1]
upcast_axis = (self.shape_len-self.upcasted, self.shape_len-self.upcasted+2, self.shape_len-self.upcasted+2)
# https://docs.nvidia.com/cuda/parallel-thread-execution/#warp-level-matrix-fragment-mma-16816-float
fix_st1 = functools.partial(fix_st, (2,2,2,2,2), (8,2,4), (2,2,2,2,2,2),
((1,1), (1,0), (0,2), (0,3), (0,4)), ((1,3), (1,4), (1,2), (0,0), (0,1), (1,5)))
fix_st2 = functools.partial(fix_st, (2,2,2,2,2), (8,2,4), (2,2,2,2,2,2),
((1,1), (1,0), (1,5), (0,0), (0,1)), ((0,4), (0,2), (1,4), (0,3), (1,3), (1,2)))
else:
raise RuntimeError("unsupported device for tensor cores")
assert apply_to_st is None, "double tensor core? not supported"
wmma_sz = [prod(l) for l in tc.thread_local_sizes]
wmma_arg = (str(tc), tc.dims, tc.dtype_in, tc.dtype_out, tuple(wmma_sz), self.opts.device, upcast_axis, tuple(reduce_axes))
ret = LazyOp(ReduceOps.WMMA, (fixup_ast(rsrc.src[0], fix_st1), fixup_ast(rsrc.src[1], fix_st2)), wmma_arg)
new_reduce_axes = tuple(i for i in arg if i not in reduce_axes)
return LazyOp(op.op, (ret,), new_reduce_axes) if new_reduce_axes else ret
if self.group_for_reduces:
start = LazyOp(op.op, tuple(fixup_ast(x, apply_to_st) for x in op.src), arg)
local_shape = (1,) * self.global_dims + self.full_shape[self.global_dims:self.global_dims+self.local_dims+self.group_for_reduces] + \
(1,) * (self.shape_len - self.upcasted - self.group_for_reduces - self.first_reduce) + tuple([x[0] for x in self.upcasted_axis(0)])
local_buffer = MemBuffer(-1, start.dtype, ShapeTracker.from_shape(local_shape))
local_store = LazyOp(BufferOps.STORE, (start,), local_buffer)
local_load = LazyOp(BufferOps.LOAD, (local_store,), local_buffer)
return LazyOp(op.op, (local_load,), tuple(range(self.first_reduce, self.first_reduce+self.group_for_reduces)))
elif op.op is MetaOps.KERNEL:
arg = KernelInfo(self.local_dims, self.upcasted, self.dont_use_locals)
else:
arg = op.arg
return LazyOp(op.op, tuple(fixup_ast(x, apply_to_st) for x in op.src), arg)
return fixup_ast(self.ast)
# **** this is the lowerer ****
def linearize(self) -> Kernel:
modified_ast = self.get_optimized_ast()
if DEBUG >= 3:
print(self.name)
print(modified_ast)
verify_lazyop(modified_ast)
uop_sink = lazyop_to_uop(modified_ast, self.opts)
print(uop_sink)
# extract global/local sizes
if self.opts.has_local:
self.global_size: Optional[List[int]] = [1,1,1]
self.local_size: Optional[List[int]] = [1,1,1]
for u in uop_sink.parents:
if u.op is UOps.SPECIAL:
if u.arg[1][0] == 'i': self.local_size = None
if u.arg[1][0] == 'l':
assert self.local_size is not None
self.local_size[u.arg[0]] = u.arg[2]
else:
self.global_size[u.arg[0]] = u.arg[2]
else:
self.global_size, self.local_size = None, None
# generate the UOpGraph
self.uops:UOpGraph = UOpGraph(uop_sink, self.opts)
if DEBUG >= 5: self.uops.print()
if getenv("GRAPHUOPS"): self.uops.graph()
return self
def to_program(self) -> Program:
self.linearize()
src = self.opts.render(name:=to_function_name(self.name), self.uops)
if getenv("RUN_PROCESS_REPLAY"):
table_name = f"process_replay_{getenv('GITHUB_RUN_ID', 'HEAD')}"
diskcache_put(table_name, id(self), (self.ast, self.opts, self.applied_opts, name, src, {k:v.value for k,v in ContextVar._cache.items()}))
ops, mem = flops_mem(self.uops.uops, ignore_indexing=True)
run_count = prod((self.global_size or []) + (self.local_size or []))
# group non-local MemBuffers by the op type (LOAD or STORE) and the buffer arg. take the max access of that buffer in bytes
mem_bytes = sum(max(x.arg.dtype.itemsize * x.arg.st.real_size() for x in group) for _, group in
itertools.groupby([x for x in self.ast.lazyops if x.op in BufferOps and isinstance(x.arg, MemBuffer) and x.arg.idx >= 0],
key=lambda x: (x.op, x.arg.idx)))
return Program(self.name, src, self.opts.device, self.global_size, self.local_size, self.uops, ops * run_count, min(mem * run_count, mem_bytes))