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499 lines
32 KiB
499 lines
32 KiB
# all of symbolic lives here now
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from typing import Any, cast
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import math, operator, struct, functools
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from collections import defaultdict
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from tinygrad.uop.ops import Ops, PatternMatcher, UPat, UOp, GroupOp, exec_alu
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from tinygrad.dtype import ConstType, dtypes, PtrDType, AddrSpace, can_safe_cast
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from tinygrad.helpers import partition, all_same, prod, flatten, get_single_element, cdiv, cmod, CORRECT_DIVMOD_FOLDING
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from tinygrad.uop.decompositions import xpow
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# ******** phase 1 of symbolic used to live in ops, it's the most generic folding rules ********
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def simplify_pow(x:UOp, c:UOp) -> UOp|None:
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if c.arg < 0: return x.reciprocal().pow(-c)
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if c.arg == 0: return x.const_like(1)
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if int(c.arg-0.5)+0.5 == c.arg: return x.pow(c.const_like(c.arg-0.5)) * x.sqrt()
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if int(c.arg) == c.arg: return (y := x.pow(c.const_like(c.arg//2))) * y * (x if c.arg%2 == 1 else 1)
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return None
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def fold_bitcast(root:UOp, c:UOp) -> UOp|None:
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if (from_fmt:=c.dtype.scalar().fmt) is None or (to_fmt:=root.dtype.scalar().fmt) is None: return None
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if c.dtype.itemsize != root.dtype.itemsize: return None
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def convert(v:Any): return struct.unpack(to_fmt, struct.pack(from_fmt, v))[0]
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return root.const_like(convert(c.arg) if root.dtype.count == 1 else tuple(map(convert, c.arg)))
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symbolic_simple = PatternMatcher([
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# ** self folding **
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(UPat.var("x") + 0, lambda x: x), # x+0 -> x
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(UPat.var("x") * 1, lambda x: x), # x*1 -> x
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(UPat.var("x", dtype=dtypes.ints) ^ 0, lambda x: x), # x^0 -> x
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(UPat.var("x") // UPat.var("x"), lambda x: x.const_like(1)), # x//x -> 1
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(UPat.var("x") // 1, lambda x: x), # x//1 -> x
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(UPat.var("x") // -1, lambda x: -x), # x//-1 -> -x
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(UPat.var("x") / UPat.var("x"), lambda x: x.const_like(1)), # x/x -> 1
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((UPat.var("x") * UPat.var("x2")) / UPat.var("x2"), lambda x,x2: x), # (x*x2)/x2 -> x
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((UPat.var() % UPat.var("y")).named("base") % UPat.var("y"), lambda base,y: base), # (x%y)%y = -> x%y (rewritten with base for speed)
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(UPat.var("x")%UPat.cvar("c")+(UPat.var("x")//UPat.cvar("c"))*UPat.cvar("c"), lambda x,c: x), # (x%c)+(x//c)*c = x
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((UPat.var("x")//UPat.cvar("c1"))*UPat.cvar("c3")+UPat.var("x")%UPat.cvar("c1")*UPat.cvar("c2"),
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lambda x,c1,c2,c3: x*c2 if c1.arg*c2.arg==c3.arg else None), # (x%c1)*c2+(x//c1)*c3 = x*c2 if c1*c2==c3
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(UPat.var("x", dtype=dtypes.bool) & UPat.cvar("c", vec=False), lambda x,c: x if c.arg else c),
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(UPat.var("x", dtype=dtypes.bool) | UPat.cvar("c", vec=False), lambda x,c: c if c.arg else x),
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(UPat(GroupOp.Idempotent, src=(UPat.var("x"), UPat.var("x"))), lambda x: x),
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(UPat.var("x", dtype=dtypes.bool).logical_not().logical_not(), lambda x: x),
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(UPat.var("x", dtype=dtypes.bool).where(UPat.const(dtypes.bool, True), UPat.const(dtypes.bool, False)), lambda x: x),
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(UPat.var("x", dtype=dtypes.ints+(dtypes.bool,)).trunc(), lambda x: x),
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# ** zero folding **
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(UPat.var("x") < UPat.var("x"), lambda x: x.const_like(False).cast(dtypes.bool.vec(x.dtype.count))), # x < x -> False
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(UPat.var("x") % UPat.var("x"), lambda x: x.const_like(0)), # x%x -> 0
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(UPat.var("x", dtype=dtypes.ints) != UPat.var("x", dtype=dtypes.ints),
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lambda x: x.const_like(False).cast(dtypes.bool.vec(x.dtype.count))), # x != x -> False (only ints)
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# x*0 -> 0 or 0*x -> 0
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# if x is nan or inf it should render the nan value.
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# NOTE: this can be wrong for loaded NaN
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(UPat.var("x") * 0, lambda x: x.const_like(float("nan") if isinstance(x.arg, float) and (math.isnan(x.arg) or math.isinf(x.arg)) else 0)),
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# ** constant folding **
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# TODO: add const folding for Ops.THREEFRY
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(UPat(GroupOp.Unary, src=(UPat((Ops.VCONST, Ops.CONST)),), name="a"), lambda a: a.const_like(exec_alu(a.op, a.dtype, [a.src[0].arg], False))),
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(UPat(GroupOp.Binary-{Ops.THREEFRY}, src=(UPat((Ops.VCONST, Ops.CONST)),)*2, name="a"),
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lambda a: a.const_like(exec_alu(a.op, a.dtype, [a.src[0].arg, a.src[1].arg], False))),
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(UPat(GroupOp.Ternary, src=(UPat((Ops.VCONST, Ops.CONST)),)*3, name="a"),
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lambda a: a.const_like(exec_alu(a.op, a.dtype, [a.src[0].arg, a.src[1].arg, a.src[2].arg], False))),
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# bool MUL is AND, ADD/MAX is OR. prevents other rules to rewrite bool ADD/MUL incorrectly
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(UPat.var('x', dtype=dtypes.bool) * UPat.var('y', dtype=dtypes.bool), lambda x,y: x&y),
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(UPat.var('x', dtype=dtypes.bool) + UPat.var('y', dtype=dtypes.bool), lambda x,y: x|y),
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(UPat.var('x', dtype=dtypes.bool).maximum(UPat.var('y', dtype=dtypes.bool)), lambda x,y: x|y),
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# *** cast/bitcast ***
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(UPat(Ops.CAST, name="root", src=(UPat.cvar("c"),)), lambda root, c: root.const_like(c.arg)),
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(UPat((Ops.CAST, Ops.BITCAST), name="root"), lambda root: root.src[0] if root.dtype == root.src[0].dtype else None),
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(UPat(Ops.BITCAST, name="root", src=(UPat.cvar("c"),)), fold_bitcast),
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# b.cast(a).cast(b) -> b if a preserves all values in b
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(UPat.var('x').cast().named('a').cast().named('b'), lambda x,a,b: x if x.dtype == b.dtype and can_safe_cast(b.dtype, a.dtype) else None),
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# ** pow **
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(UPat.var("x").alu(Ops.POW, UPat.cvar("c", vec=False)), simplify_pow),
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# positive const ** x
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(UPat.cvar("c", vec=False).alu(Ops.POW, UPat.var("x")), lambda c,x: c if c.arg == 1 else (x*math.log2(c.arg)).exp2() if c.arg > 0 else None),
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# rules for threefry
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((UPat.var('x', dtypes.uint64)&0xFFFFFFFF).cast(dtypes.uint32), lambda x: x.cast(dtypes.uint32)&0xFFFFFFFF), # TODO: why is the and needed?
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(((UPat.var(None, dtypes.uint64)*(1<<32)) | UPat.var('y', dtypes.uint32).cast(dtypes.uint64)).cast(dtypes.uint32), lambda y: y),
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(((UPat.var('x', dtypes.uint64)*(1<<32)) | UPat.var(None, dtypes.uint32).cast(dtypes.uint64))//(1<<32), lambda x: x),
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# hacks for threefry long removal when padded (TODO: genericize)
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(UPat.var('x', dtypes.uint32).cast(dtypes.uint64) * UPat.var('y').where(UPat.const(dtypes.uint64, 1<<32), UPat.const(dtypes.uint64, 0)),
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lambda x,y: y.where(x, 0).cast(dtypes.uint64) * (1<<32)),
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((UPat.var('x', dtypes.uint64)&(UPat.var('y').where(UPat.const(dtypes.uint64, 0xFFFFFFFF), UPat.const(dtypes.uint64, 0)))).cast(dtypes.uint32),
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lambda x,y: y.where(x.cast(dtypes.uint32), 0)),
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# new decomp rules for threefry
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(((UPat.var(None, dtypes.uint64)<<32) | UPat.var('y', dtypes.uint32).cast(dtypes.uint64)).cast(dtypes.uint32), lambda y: y),
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(((UPat.var('x', dtypes.uint64)<<32) | UPat.var(None, dtypes.uint32).cast(dtypes.uint64))>>32, lambda x: x),
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(UPat.var('b').where(UPat.var('x', dtypes.uint32).cast(dtypes.uint64), UPat.const(dtypes.uint64, 0)).cast(dtypes.uint32), lambda b,x: b.where(x,0))
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])
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# ******** phase 2 builds on phase 1, it includes the old "symbolic", rules that match deeper ********
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def split_uop(x:UOp, sep:Ops):
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if x.op is sep:
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for s in x.src: yield from split_uop(s, sep)
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else: yield x
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def fold_unrolled_divs(divs:UOp, denominator: int, fac=1) -> UOp|None:
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# div pattern in unrolled arange
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# example: (x//4+(x+1)//4+(x+2)//4+(x+3)//4 -> x
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seen_const, ans = [], None
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for u in split_uop(divs, Ops.ADD):
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if fac!=1:
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if u.op is not Ops.MUL or u.src[1].op is not Ops.CONST or u.src[1].arg != fac: return None
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u = u.src[0]
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if not (u.op is Ops.IDIV and u.src[1].op is Ops.CONST): return None
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if denominator != u.src[1].arg: return None
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if (s0:=u.src[0]).vmin < 0: return None
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# assumed CONST is the last of an ADD
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if s0.op is Ops.ADD and s0.src[1].op is Ops.CONST and s0.src[1].op is Ops.CONST:
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seen_const.append(s0.src[1].arg)
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s0 = s0.src[0]
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else: seen_const.append(0)
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if ans is None: ans = s0
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if ans is not s0: return None
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if ans is None: return None
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# the first (denominator-len(seen_const)) terms may have been folded to 0 already
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for i in range(denominator-len(seen_const)):
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if ans is not None and 0 <= ans.vmin and ans.vmax + i < denominator: seen_const.append(i)
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if sorted(seen_const)==list(range(denominator)):
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return fac*ans
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return None
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def lt_folding(x:UOp, c:int) -> UOp|None:
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p, np = partition(split_uop(x, Ops.ADD), lambda u: u.const_factor() == 1)
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if np and (d:=math.gcd(*[u.const_factor() for u in np], c)) > 1 and 0 <= sum(u.vmin for u in p) and sum(u.vmax for u in p) < d:
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return cast(UOp, functools.reduce(operator.add, np).divides(d))<(c//d)
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return None
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def canonicalize_simplex(X:UOp) -> UOp|None:
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# (X := a0*x0 + a1*x1 + ...) > 0 is equivalent to x0 + x1 + ... > 0 if xi >= 0 and ai > 0 for ints.
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# returns x0 + x1 + ... in such case, or None if not
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changed, ret = False, []
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for u in split_uop(X, Ops.ADD):
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# assumed the const is the last src of MUL
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if u.op is Ops.MUL and u.src[1].op is Ops.CONST and u.src[1].arg > 0:
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changed = True
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u = u.src[0]
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if not (u.op in GroupOp.Irreducible and u.vmin >= 0): return None
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ret.append(u)
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return functools.reduce(operator.add, ret) if changed else None
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def cancel_divmod(d: UOp, x: UOp, y: UOp) -> UOp|None:
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# simple cancel div/mod case when the range of the numerator lies within a single denominator interval
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x_min, x_max, y_min, y_max = x.vmin, x.vmax, y.vmin, y.vmax
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assert isinstance(x_min, int) and isinstance(x_max, int) and isinstance(y_min, int) and isinstance(y_max, int)
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if y_min==y_max==0: raise ZeroDivisionError(f"{'Division' if d.op is Ops.IDIV else 'Mod'} by zero trying to rewrite {x.alu(d.op, y)}")
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if y_min*y_max > 0 and (q:=cdiv(x_min,y_min)) == cdiv(x_min,y_max) == cdiv(x_max,y_min) == cdiv(x_max,y_max):
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return x - q*y if d.op is Ops.MOD else d.const_like(q)
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return None
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def remove_nested_mod(m: UOp, x: UOp, y: UOp) -> UOp|None:
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# remove nested mod in case the inner mod is a multiple of the outer mod
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# example: (a%4 + b)%2 -> (a+b)%2
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if ((c := y.arg) < 0) or x.vmin<0: return None
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new_xs = []
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something_changed = False
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for u in split_uop(x, Ops.ADD):
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if u.op is Ops.MOD:
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if u.src[1].divides(c) is not None:
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something_changed = True
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u = u.src[0]
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new_xs.append(u)
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new_x: UOp = functools.reduce(operator.add, new_xs)
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if something_changed and new_x.vmin>=0: return new_x % y
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return None
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def fold_binary_numerator(d: UOp, x: UOp, y: UOp) -> UOp|None:
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# we can fold if the expression has only one non-constant term and this term can only take on two values
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if ((c := y.arg) < 0) or (x.dtype.count > 1): return None
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x,const = x.pop_const()
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terms, factors = zip(*[(u.divides(f:=u.const_factor()),f) for u in split_uop(x, Ops.ADD)])
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if len(terms)==1 and (v:=terms[0]).vmax-v.vmin == 1:
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y1 = cmod(factors[0]*v.vmin+const, c) if d.op is Ops.MOD else cdiv(factors[0]*v.vmin+const, c) # type: ignore
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y2 = cmod(factors[0]*v.vmax+const, c) if d.op is Ops.MOD else cdiv(factors[0]*v.vmax+const, c) # type: ignore
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return (y2-y1)*(v-v.vmin) + y1
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return None
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def fold_divmod_congruence(d: UOp, x: UOp, y: UOp) -> UOp|None:
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# within a mod we can freely subtract multiples of c, we use this to see if a is congruent to an expression whose vmin/vmax are between 0 and c
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if (x.vmin<0 and CORRECT_DIVMOD_FOLDING) or ((c := y.arg) < 0) or (x.dtype.count > 1): return None
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x,const = x.pop_const()
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terms, factors = zip(*[(u.divides(f:=u.const_factor()),f) for u in split_uop(x, Ops.ADD)])
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# a//c = (a-a%c)/c, if we can fold a%c, we can fold a//c
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rems = [min((r:=f%c), r-c, key=abs) for f in factors]
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if (rem:=sum(r*v for r,v in zip(rems,terms))+const%c).vmin//c==rem.vmax//c and all(f > 0 for f in factors):
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if d.op is Ops.MOD: return rem - rem.vmin//c*c
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return sum((f-r)//c * v for f,r,v in zip(factors,rems,terms)) + (const-const%c+rem.vmin//c*c)//c
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return None
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def divide_by_gcd(d: UOp, x: UOp, y: UOp) -> UOp|None:
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# x//y -> (x//gcd)//(y//gcd) or x%y -> gcd*(x//gcd)%(y//gcd)
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terms, factors = zip(*[(u.divides(f:=u.const_factor()),f) for u in split_uop(x, Ops.ADD)])
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if (gcd := math.gcd(y.arg, *factors)) == 1: return None
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ret = sum(f//gcd * v for f,v in zip(factors, terms)).alu(d.op, y.const_like(y.arg//gcd))
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return ret*gcd if d.op is Ops.MOD else ret
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def nest_div_by_smallest_factor(d: UOp, x: UOp, y: UOp) -> UOp|None:
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# we try and nest the div and see if it allows the numerator to be simplified
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if ((c := y.arg) < 0) or (x.dtype.count > 1): return None
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factors = [u.const_factor() for u in split_uop(x.pop_const()[0], Ops.ADD)]
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# div is the smallest factor of the denominator (greater than 1) out of all "factors"
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# TODO: there are better ways to pick `div`, this sometimes adds extra divisions
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# TODO: add same optimization for mod
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div = min([y.arg]+[abs(f) for f in factors if abs(f) > 1 and (c%f)==0])
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if (1 < div < c) and (newxs:=(newx:=(x//div)).simplify()) is not newx and x.vmin>=0 and newx.vmin>=0: return newxs//(c//div)
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return None
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def simplify_remainder(d: UOp, x: UOp, y: UOp) -> UOp|None:
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# we try and take out the quotient and see if it allows the numerator to be simplified
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if ((c := y.arg) < 0) or (x.dtype.count > 1): return None
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x_no_const,const = x.pop_const()
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terms, factors = zip(*[(u.divides(f:=u.const_factor()),f) for u in split_uop(x_no_const, Ops.ADD)])
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quotients, remainders = zip(*[divmod(f, c) for f in factors])
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gcd = math.gcd(c, *remainders) # gcd without const!
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if const%c==const and gcd==1 and not any(r==0 or (r!=f and d.op is Ops.MOD) for r,f in zip(remainders, factors)): return None
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quo, rem = x.const_like(const//c), x.const_like((const%c)//gcd)
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for q,r,f,v in zip(quotients, remainders, factors, terms):
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if d.op is Ops.IDIV and r!=0:
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rem += f//gcd * v
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else:
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rem += r//gcd * v
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quo += q * v
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# if numerator before/after is negative, and it has remainder, don't simplify because C divmod is different from python divmod.
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if (x.vmin < 0 or rem.vmin < 0) and remainders: return None
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if d.op is Ops.MOD: return gcd*(rem % (c//gcd)) + const%gcd
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return rem//(c//gcd)+quo
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def gep_through_wmma(gep:UOp, wmma:UOp):
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out_sz = prod(x[1] for x in wmma.arg[6][-1])
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wmma_idxs = gep.arg[::out_sz]
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for i in range(out_sz):
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if tuple(x-i for x in gep.arg[i::out_sz]) != wmma_idxs: return None
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tsrcs = []
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for s,sz in zip(wmma.src, wmma.arg[6]):
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src_args = []
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ssz = prod(x[1] for x in sz)
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for w in wmma_idxs: src_args += list(range((w//out_sz)*ssz, (w//out_sz)*ssz + ssz))
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tsrcs.append(s.gep(tuple(src_args)))
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return UOp(Ops.WMMA, gep.dtype, tuple(tsrcs), wmma.arg)
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gep_pushing = PatternMatcher([
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# GEP/VECTORIZE, GEP/GEP, GEP/CONST, GEP/VCONST
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(UPat(Ops.GEP, src=(UPat(Ops.GEP, name='g2'),), name='g1'),
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lambda g1, g2: g2.src[0].gep(tuple(g2.arg[g1.arg[i]] for i in range(len(g1.arg))))),
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(UPat(Ops.GEP, src=(UPat(Ops.VECTORIZE, name="vec"),), name="gep"),
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lambda gep, vec: UOp(Ops.VECTORIZE, gep.dtype, tuple(vec.src[i] for i in gep.arg)) if len(gep.arg) > 1 else vec.src[gep.arg[0]]),
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(UPat(Ops.GEP, src=(UPat.cvar("c", vec=False),), name="gep"), lambda gep, c: gep.const_like(c.arg)),
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(UPat(Ops.GEP, src=(UPat(Ops.VCONST, name="c"),), name="gep"), lambda gep, c: gep.const_like(tuple(c.arg[x] for x in gep.arg))),
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# GEP on void is skipped
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(UPat(Ops.GEP, src=(UPat(dtype=dtypes.void, name="x"),)), lambda x: x),
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# GEP in order is removed
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(UPat(Ops.GEP, name="g"), lambda g: g.src[0] if not isinstance(g.dtype, PtrDType) and g.arg == tuple(range(g.src[0].dtype.count)) else None),
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# push all GEPs through ALUs (fix arange stuff)
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(UPat(Ops.GEP, src=(UPat((*GroupOp.ALU, Ops.CAST, Ops.BITCAST), name='alu'),), name='gep'),
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lambda gep,alu: UOp(alu.op, alu.dtype.scalar().vec(gep.dtype.count), tuple(x.gep(gep.arg) for x in alu.src), alu.arg) \
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if not isinstance(gep.dtype, PtrDType) else None),
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# CAT can't be rendered. it's a VECTORIZE on vectors, we expand to a single VECTORIZEs with GEPs (TODO: move this later)
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(UPat(Ops.CAT, name="x"), lambda x: UOp(Ops.VECTORIZE, x.dtype, tuple(y.gep(i) for y in x.src for i in range(y.dtype.count))) \
|
|
if not isinstance(x.dtype, PtrDType) else None),
|
|
# VECTORIZE on same GEP
|
|
(UPat(Ops.VECTORIZE, name="v", src=UPat(Ops.GEP, src=(UPat.var("x"),))), lambda v,x: x.gep(tuple(get_single_element(i.arg) for i in v.src))),
|
|
# push some GEPs through WMMAs
|
|
(UPat(Ops.GEP, src=(UPat(Ops.WMMA, name="wmma"),), name="gep"), gep_through_wmma),
|
|
])
|
|
|
|
commutative = PatternMatcher([
|
|
# ** COMMUTATIVE flipping (only for ints) **
|
|
# NOTE: this can break merging vector math by only flipping some of them
|
|
(UPat(GroupOp.Commutative, dtype=dtypes.int, name='x'), lambda x: x.replace(src=x.src[::-1]) if x.src[1].tuplize < x.src[0].tuplize else None),
|
|
])
|
|
|
|
symbolic = symbolic_simple+commutative+PatternMatcher([
|
|
# ** boolean algebra **
|
|
(UPat.var("x") | (UPat.var("x") & UPat.var()), lambda x: x), # x|(x&y) -> x
|
|
# ** combine terms **
|
|
(UPat.var("x") * UPat.cvar("c0") + UPat.var("x") * UPat.cvar("c1"), lambda x,c0,c1: x*(c0+c1)), # (x*c0)+(x*c1) -> x*(c0+c1)
|
|
((UPat.var("y") + UPat.var("x") * UPat.cvar("c0")) + UPat.var("x") * UPat.cvar("c1"), lambda x,y,c0,c1: y+x*(c0+c1)),
|
|
(UPat.var("x") + UPat.var("x") * UPat.cvar("c"), lambda x,c: x*(c+1)), # (x+x*c)-> x*(c+1)
|
|
((UPat.var("y") + UPat.var("x")) + UPat.var("x") * UPat.cvar("c"), lambda x,y,c: y+x*(c+1)),
|
|
(UPat.var("x") + UPat.var("x"), lambda x: x*2), # (x+x)-> x*2
|
|
((UPat.var("y") + UPat.var("x")) + UPat.var("x"), lambda y,x: y+x*2),
|
|
((UPat.var("x") / UPat.var("x2")) / UPat.var("x3"), lambda x,x2,x3: x/(x2*x3) if x2 is not x3 else None), # (x/x2)/x3 -> x/(x2*x3)
|
|
(-1 * (UPat.var("x") + UPat.cvar("c")), lambda x,c: (-x)+(-c)), # -(x+c) -> -x + -c
|
|
# a conditional with the same results either way is a noop, also fold const conditionals
|
|
(UPat.var().where(UPat.var("val"), UPat.var("val")), lambda val: val),
|
|
(UPat.cvar("gate", vec=False).where(UPat.var("c0"), UPat.var("c1")), lambda gate, c0, c1: c0 if gate.arg else c1),
|
|
(UPat.var("cond", dtype=dtypes.bool).logical_not().where(UPat.var("t"), UPat.var("f")), lambda cond, t, f: cond.where(f,t)),
|
|
# alu of two where with same conds can combine, only do if true branch or false branch is const
|
|
(UPat(GroupOp.Binary, name="alu", src=(UPat.var("c").where(UPat.var("t"), UPat.var("f")), UPat.var("c").where(UPat.var("tt"), UPat.var("ff")))), \
|
|
lambda alu,c,t,tt,f,ff: c.where(t.alu(alu.op, tt), f.alu(alu.op, ff)) if t.op == tt.op == Ops.CONST or f.op == ff.op == Ops.CONST else None),
|
|
# ALU/variable min==max -> CONST (slow!)
|
|
(UPat(GroupOp.ALU|{Ops.DEFINE_VAR, Ops.SPECIAL, Ops.RANGE}, name="x"), lambda x: x.const_like(x.vmin) if x.vmin == x.vmax else None),
|
|
# max folding
|
|
(UPat.maximum(UPat.var("x"), UPat.var("y")), lambda x,y: x if x.vmin >= y.vmax else y if x.vmax <= y.vmin else None),
|
|
# TODO: why does this rule break beautiful_mnist?
|
|
#((UPat.var("x")+UPat.var("z")).maximum(UPat.var("y")+UPat.var("z")), lambda x,y,z: x.maximum(y) + z),
|
|
#((UPat.var("x")*UPat.cvar("c1")).maximum(UPat.var("x")*UPat.cvar("c2")), max_var_const),
|
|
# ** two stage ALU folding **
|
|
*((UPat.var("x").alu(op, UPat.cvar("c1")).alu(op, UPat.cvar("c2")).named("f"),
|
|
lambda f,x,c1,c2: x.alu(f.op,c1.alu(f.op,c2))) for op in GroupOp.Associative),
|
|
((UPat.cvar("c0") + UPat.var("x")) < UPat.cvar("c1"), lambda x,c0,c1: x<(c1-c0)), # c0 + x < c1 -> x < c1 - c0
|
|
((UPat.var("x") // UPat.cvar("c1")) // UPat.cvar("c2"), lambda x,c1,c2: x//(c1*c2)), # (x//c1)//c2 -> x//(c1*c2)
|
|
# ** lt **
|
|
# c0*x<c1 for positive int c0,c1
|
|
((UPat.cvar("c0", vec=False)*UPat.var("x", dtype=dtypes.ints))<UPat.cvar("c1", vec=False),
|
|
lambda x,c0,c1: x<math.ceil(c1.arg/c0.arg) if c0.arg > 0 and c1.arg > 0 else None),
|
|
# c0*x<c1 for negative int c0 and non-positive c1
|
|
((UPat.cvar("c0", vec=False)*UPat.var("x", dtype=dtypes.ints))<UPat.cvar("c1", vec=False),
|
|
lambda x,c0,c1: (-x)<(-(math.floor(-c1.arg/-c0.arg))) if c0.arg < 0 and c0.arg != -1 and c1.arg <= 0 else None),
|
|
# x//d<c
|
|
((UPat.var("x", dtype=dtypes.ints)//UPat.cvar("d", vec=False))<UPat.cvar("c", vec=False),
|
|
lambda x,d,c: (x<(c.arg*d.arg) if c.arg > 0 else x<(c.arg*d.arg-(d.arg-1))) if d.arg > 0 else None),
|
|
# ** move add/mul consts to end (NOTE: this is still happening before constant folding) **
|
|
((UPat.var("x") + UPat.cvar("c1")) + UPat.var("y"), lambda x,c1,y: (x+y)+c1),
|
|
((UPat.var("x") * UPat.cvar("c1")) * UPat.var("y"), lambda x,c1,y: (x*y)*c1),
|
|
# *** rules from symbolic ***
|
|
# unrolled arange div folding
|
|
((UPat() + UPat()//UPat.cvar("d", vec=False)).named("divs"), lambda divs,d: fold_unrolled_divs(divs, d.arg)),
|
|
((UPat() + (UPat()//UPat.cvar("d", vec=False))*UPat.cvar("c")).named("divs"), lambda divs,d,c: fold_unrolled_divs(divs, d.arg, c.arg)),
|
|
# generic lt folding
|
|
(UPat.var("x", dtypes.sints)<UPat.cvar("c", vec=False), lambda x,c: lt_folding(x, c.arg) if 0 < c.arg else None),
|
|
(UPat.var("x", dtypes.sints)*-1 < UPat.var("y", dtypes.sints)*-1, lambda x,y: y<x),
|
|
# canonicalize a simplex with positive coefficients > 0
|
|
# not x < 1 -> X > 0
|
|
((UPat.var("x", dtypes.ints)<1).ne(True), lambda x: (newx<1).ne(True) if (newx:=canonicalize_simplex(x)) is not None else None),
|
|
# ** div **
|
|
# div folding
|
|
((UPat.var("x")//UPat.cvar("c") + UPat.cvar("a"))//UPat.cvar("d"), lambda x,c,a,d: (x+a*c)//(c*d)
|
|
if c.vmin>0 and d.vmin>0 and ((x.vmin>=0 and a.vmin>=0) or (x.vmax<=0 and a.vmax<=0)) else None), # (x//c+a)//d -> (x+a*c)//(c*d)
|
|
(UPat((Ops.IDIV, Ops.MOD), dtypes.sints, name="d", src=(UPat.var("x"), UPat.var("y"))), cancel_divmod),
|
|
(UPat((Ops.IDIV, Ops.MOD), dtypes.sints, name="d", src=(UPat.var("x"), UPat.cvar("y", vec=False))), fold_binary_numerator),
|
|
(UPat((Ops.IDIV, Ops.MOD), dtypes.sints, name="d", src=(UPat.var("x"), UPat.cvar("y", vec=False))), fold_divmod_congruence),
|
|
(UPat((Ops.IDIV, Ops.MOD), dtypes.sints, name="d", src=(UPat.var("x"), UPat.cvar("y", vec=False))), divide_by_gcd),
|
|
(UPat(Ops.MOD, dtypes.sints, name="m", src=(UPat.var("x"), UPat.cvar("y", vec=False))), remove_nested_mod),
|
|
(UPat((Ops.IDIV), dtypes.sints, name="d", src=(UPat.var("x"), UPat.cvar("y", vec=False))), nest_div_by_smallest_factor),
|
|
(UPat((Ops.IDIV, Ops.MOD), dtypes.sints, name="d", src=(UPat.var("x"), UPat.cvar("y", vec=False))), simplify_remainder),
|
|
(UPat.var("x") // UPat.var("d"), lambda x,d: -(x//(-d)) if d.vmax < 0 else None),
|
|
(UPat.var("x") // UPat.var("d"), lambda x,d: -((-x)//d) if x.vmax <=0 else None),
|
|
((UPat.var("x", dtypes.sints)+UPat.cvar("c", vec=False)).named("n")//UPat.cvar("d", vec=False),
|
|
lambda x,c,n,d: (-(-(c.arg%d.arg + x - (d.arg-1))//d) + c.arg//d.arg) if x.vmax<=0 and n.vmin>=0 and d.arg>0 else None),
|
|
# ** mod **
|
|
# mod folding
|
|
(UPat.var("x") % UPat.var("d"), lambda x,d: -((-x)%d) if x.vmax <= 0 else None),
|
|
(UPat.var("x") % UPat.var("d"), lambda x,d: (x%(-d)) if d.vmax < 0 else None),
|
|
])+gep_pushing
|
|
|
|
symbolic_flat = symbolic+PatternMatcher([
|
|
# ** combine terms (opinionated) **
|
|
(-1 * (UPat.var("x") + UPat.var("y")), lambda x,y: (-x)+(-y)), # -(x+y) -> -x + -y
|
|
# (x+y)*c -> x*c+y*c. only for int, float has inf*0=nan issue
|
|
((UPat.var("x", dtypes.ints) + UPat.var("y")) * UPat.cvar("c"), lambda x,y,c: x*c+y*c),
|
|
])
|
|
|
|
# ******** we take a small aside to "simplify_valid" to rewrite valids ********
|
|
|
|
def parse_valid(valid:UOp) -> tuple[UOp, bool, int]:
|
|
# if it's X <= c, returns X, True, c
|
|
# if it's X >= c, returns X, False, c
|
|
|
|
# (X < c).ne(True) -> X >= c
|
|
if valid.op is Ops.CMPNE and valid.src[1].op is Ops.CONST and valid.src[1].arg == 1 and \
|
|
(s0:=valid.src[0]).op is Ops.CMPLT and s0.src[1].op is Ops.CONST: return s0.src[0], False, s0.src[1].arg
|
|
# X < c -> X <= c-1
|
|
if valid.op is Ops.CMPLT and valid.src[1].op is Ops.CONST and dtypes.is_int(valid.src[0].dtype): return valid.src[0], True, valid.src[1].arg-1
|
|
raise ValueError(f"not able to parse {valid=}")
|
|
|
|
def uop_given_valid(valid:UOp, uop:UOp) -> UOp|None:
|
|
# return None if valid is always False, otherwise the simplified uop (might be the same as input)
|
|
|
|
# first, parse valid into {expr: (lower_bound, upper_bound)}
|
|
bounds:defaultdict[UOp, list[ConstType|None]] = defaultdict(lambda: [None, None])
|
|
for stmt in split_uop(valid, Ops.AND):
|
|
try: expr, is_upper, c = parse_valid(stmt)
|
|
except ValueError: return uop # give up if we cannot parse the valid
|
|
bounds[expr][int(is_upper)] = c
|
|
|
|
# don't simplify any other gates, can lead to OOB, we substitute them back later
|
|
uop = uop.substitute((load_subs:={u: UOp(Ops.NOOP, arg=u) for u in uop.toposort() if u.op is Ops.INDEX}))
|
|
|
|
# simplify uop given that valid is True
|
|
for expr,v in bounds.items():
|
|
v0, v1 = (expr.vmin if v[0] is None else v[0], expr.vmax if v[1] is None else v[1])
|
|
# some expr has lower bound > upper bound -> valid is an empty set and we return None
|
|
if v0 > v1: return None
|
|
# whole node became a const
|
|
if v0 == v1:
|
|
uop = uop.substitute({expr:expr.const_like(v0)}).simplify()
|
|
continue
|
|
# every candidate is a set of constrained UOp based on valid, and if every item in a set simplifies the uop into a same output, we rewrite uop
|
|
candidates = []
|
|
if expr.op is Ops.ADD and v0 == 1 and all(u.op in GroupOp.Irreducible for u in split_uop(expr, Ops.ADD)):
|
|
# if the constraint is a simplex: X0 + X1 + ... > 0, we can check if all Xi > 0 simplify into the same output
|
|
candidates.append([(Xi, UOp.variable("fake", 1, Xi.vmax, Xi.dtype)) for Xi in split_uop(expr, Ops.ADD)])
|
|
# try checking the whole clause
|
|
if expr in uop.toposort(): candidates.append([(expr, UOp.variable("fake", v0, v1, expr.dtype))])
|
|
|
|
for candidate in candidates:
|
|
# if every branch in candidate gives the same simplified uop, we can rewrite the uop
|
|
newuops = [uop.substitute({X:newX}).simplify().substitute({newX:X}).simplify() for X,newX in candidate]
|
|
if uop.op is Ops.VECTORIZE and len(uop.src) == 2:
|
|
if all_same([uops.src[0] for uops in newuops]): uop = uop.replace(src=(newuops[0].src[0], uop.src[1]))
|
|
if all_same([uops.src[1] for uops in newuops]): uop = uop.replace(src=(uop.src[0], newuops[0].src[1]))
|
|
elif all_same(newuops): uop = newuops[0]
|
|
|
|
# put the loads back in
|
|
uop = uop.substitute({v:k for k,v in load_subs.items()})
|
|
return uop
|
|
|
|
def _valid_priority(v: UOp, valids:list[UOp]):
|
|
# we want valid that's in other valids' parents to be first, so it's more likely the other valids get simplified
|
|
try: return sum(-1 if parse_valid(v)[0] in other.toposort() else 0 for other in valids)
|
|
except ValueError: return 0
|
|
|
|
def simplify_valid(valid:UOp) -> UOp|None:
|
|
ret:list[UOp] = []
|
|
something_changed = False
|
|
valids = list(split_uop(valid, Ops.AND))
|
|
for stmt in sorted(valids, key=lambda v: _valid_priority(v, valids)):
|
|
# TODO: root cause this and test_simplify_valid_from_div
|
|
if stmt.op is Ops.CAST: return None
|
|
ret.append(newstmt if ret and (newstmt:=uop_given_valid(functools.reduce(operator.and_, ret), stmt)) is not None else stmt)
|
|
if ret[-1] is not stmt: something_changed = True
|
|
return functools.reduce(operator.and_, ret) if something_changed else None
|
|
|
|
# ******** phase 3 is the complete symbolic, and deals with very complex things like loop rewriting and threefry transform ********
|
|
|
|
def reduce_mul_chain(r:UOp):
|
|
if r.arg not in {Ops.ADD, Ops.MAX}: return None
|
|
if r.dtype != r.src[0].dtype: return None
|
|
inside, outside = [], []
|
|
for m in split_uop(r.src[0], Ops.MUL):
|
|
m_parents = m.toposort()
|
|
if all(r not in m_parents for r in r.src[1:]) and (r.arg != Ops.MAX or m.vmin >= 0): outside.append(m)
|
|
else: inside.append(m)
|
|
if len(outside) == 0: return None
|
|
return r.replace(src=(prod(inside) if len(inside) else r.src[0].const_like(1),)+r.src[1:])*prod(outside)
|
|
|
|
# this is symbolic 2.0
|
|
REMOVE_FROM_SINK = {Ops.SINK, Ops.UNROLL, Ops.PTRCAT, Ops.CAT, Ops.NOOP}
|
|
REMOVE_FROM_BARRIER = {Ops.VECTORIZE, Ops.SINK, Ops.CAT, Ops.PTRCAT, Ops.NOOP}
|
|
sym = symbolic_flat+PatternMatcher([
|
|
# LOAD/STORE -> NOOP
|
|
(UPat.var('x').store(UPat.var('x').load(), allow_any_len=True), lambda x: None if x.dtype.addrspace != AddrSpace.REG else x.src[0].src[0]),
|
|
(UPat(Ops.LOAD, src=(UPat.cvar('c'))), lambda c: c),
|
|
# VECTORIZE/CONST, VECTORIZE/GEP
|
|
(UPat(Ops.VECTORIZE, src=UPat(Ops.CONST), name="vec"), lambda vec: UOp.const(vec.dtype, tuple(x.arg for x in vec.src))),
|
|
(UPat(Ops.VECTORIZE, src=UPat(Ops.GEP, src=(UPat.var("x"),)), name="vec"), lambda vec,x: x.gep(tuple(y.arg[0] for y in vec.src))),
|
|
# reorder ALU/VECTORIZE
|
|
(UPat(GroupOp.ALU, src=(UPat(Ops.VECTORIZE, src=UPat(name='x')), UPat(Ops.VECTORIZE, src=UPat(name='y'))), name='alu'),
|
|
lambda x,y,alu: UOp(Ops.VECTORIZE, alu.dtype, (UOp(alu.op, alu.dtype.scalar(), (x,y)),)*alu.dtype.count)),
|
|
# VECTORIZE of a single element is just that element
|
|
(UPat(Ops.VECTORIZE, src=(UPat(name='x'),)), lambda x: x),
|
|
# VECTORIZE void is SINK
|
|
(UPat(Ops.VECTORIZE, dtype=dtypes.void, src=UPat(Ops.BARRIER, name='b')), lambda b: b),
|
|
(UPat(Ops.VECTORIZE, dtype=dtypes.void, name='x'), lambda x: UOp(Ops.SINK, dtypes.void, x.src)),
|
|
# tensor core with a 0 input is acc
|
|
(UPat(Ops.WMMA, src=(UPat.const(None, 0.0), UPat.var(), UPat.var("acc"))), lambda acc: acc),
|
|
(UPat(Ops.WMMA, src=(UPat.var(), UPat.const(None, 0.0), UPat.var("acc"))), lambda acc: acc),
|
|
# ** self folding **
|
|
# x!=0 -> (bool)x
|
|
(UPat.var("x")!=0, lambda x: x.cast(dtypes.bool.vec(x.dtype.count))),
|
|
# ** where **
|
|
# push cast to branches
|
|
(UPat.var("s").where(UPat.var("a"), UPat.var("b")).cast().named("cast"), lambda s,a,b,cast: s.where(a.cast(cast.dtype), b.cast(cast.dtype))),
|
|
# a.where(b.where(c, d), d) -> (a & b).where(c, d)
|
|
(UPat.var("a").where(UPat.var("b").where(UPat.var("c"), UPat.var("d")), UPat.var("d")), lambda a,b,c,d: (a&b).where(c,d)),
|
|
# ** pow **
|
|
((UPat(Ops.POW, name="p"), lambda p: xpow(*p.src))),
|
|
# index true is index without op
|
|
(UPat(Ops.INDEX, src=(UPat.var("b"), UPat.var("idx"), UPat.const(dtypes.bool, True))), lambda b, idx: b.index(idx)),
|
|
# ** load/store folding **
|
|
(UPat.store(UPat(Ops.INDEX, name="index"), UPat.load(UPat(Ops.INDEX, name="index"))), lambda index: UOp(Ops.NOOP)),
|
|
(UPat.store(UPat(Ops.INDEX, name="index"), UPat.var("gate").where(UPat.var("alt"),
|
|
UPat.load(UPat(Ops.INDEX, name="index"))), allow_any_len=True, name="store"),
|
|
lambda index, gate, alt, store: UOp.store(index.src[0].index(index.src[1], gate), alt, *store.src[2:])),
|
|
# fold gated LOAD/STORE
|
|
(UPat().index(UPat(), UPat.const(dtypes.bool, True)).named("idx"), lambda idx: idx.replace(src=idx.src[0:2])), # remove True
|
|
(UPat((Ops.LOAD, Ops.STORE), src=(UPat().index(UPat(), UPat.const(dtypes.bool, False)).or_casted(),), allow_any_len=True, name="x"),
|
|
lambda x: UOp(Ops.NOOP) if x.op is Ops.STORE else x.const_like(0)), # NULL pointer store does nothing. NULL pointer load produces 0
|
|
# remove VECTORIZE from SINK/BARRIER. TODO: SINK/BARRIER are really the same thing at GLOBAL/LOCAL levels
|
|
(UPat(Ops.BARRIER, name="root"),
|
|
lambda root: UOp(Ops.BARRIER, root.dtype, tuple(flatten(x.src if x.op in REMOVE_FROM_BARRIER else (x,) for x in root.src)), root.arg)
|
|
if any(x.op in REMOVE_FROM_BARRIER for x in root.src) else None),
|
|
(UPat(Ops.SINK, name="root"),
|
|
lambda root: UOp(Ops.SINK, root.dtype, tuple(flatten(x.src if x.op in REMOVE_FROM_SINK else (x,) for x in root.src)), root.arg)
|
|
if any(x.op in REMOVE_FROM_SINK for x in root.src) else None),
|
|
((UPat.var("x") * UPat.var("x")).reciprocal(), lambda x: x.reciprocal()*x.reciprocal()), # 1/(x^c) -> (1/x)^c
|
|
((UPat.var("x") * UPat.var("x") * UPat.var("x")).reciprocal(), lambda x: x.reciprocal()*x.reciprocal()*x.reciprocal()),
|
|
((UPat.var("x") * UPat.cvar("c")).reciprocal(), lambda x,c: x.reciprocal()*c.reciprocal()), # 1/(x*c) -> (1/c)*(1/x)
|
|
(UPat.var("x") * ((1+UPat.var("x")).reciprocal().named("d")), lambda x,d: 1-d), # x*/(1+x) -> 1-1/(1+x)
|
|
(UPat.var("x") * ((1+UPat.var("x")).reciprocal().named("d")*UPat.var("y")), lambda x,y,d: y*(1-d)),
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(UPat.var("x") * ((1+UPat.var("x")).reciprocal().named("d")+UPat.var("y")), lambda x,y,d: (1-d)+x*y),
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# move const multiply after REDUCE (NOTE: the mul chain can do this, but only if it's a same dtype reduce)
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((UPat.var("x")*UPat.cvar("c", vec=False)).reduce(arg=Ops.ADD, name="r", allow_any_len=True), lambda x,c,r: r.replace(src=(x,)+r.src[1:])*c.arg),
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# reduce mul chain, move muls after the reduce
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(UPat(Ops.MUL).reduce(name="r", allow_any_len=True), reduce_mul_chain),
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])
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