Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

[Arith] Simplify the result of non-divisible floordiv #15881

Merged
merged 1 commit into from
Oct 7, 2023
Merged

[Arith] Simplify the result of non-divisible floordiv #15881

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
9 changes: 9 additions & 0 deletions src/arith/iter_affine_map.cc
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1904,6 +1904,15 @@ PrimExpr IterMapRewriter::SplitFloorDivConst(IterSplitExpr lhs, PrimExpr base, P
/* lower_factor = */ padded->lower_factor * rhs,
/* extent = */ analyzer_->Simplify(floordiv(padded->extent, rhs)),
/* scale = */ padded->scale);
} else if (is_one(padded->lower_factor) &&
analyzer_->CanProveEqual(padded->extent, padded->source->extent)) {
// floordiv(floormod(floordiv(iter, lower_factor), ext), c)
// = floordiv(iter, c)
// when lower_factor = 1 and ext = iter.extent
new_split = IterSplitExpr(padded->source,
/* lower_factor = */ rhs,
/* extent = */ analyzer_->Simplify(ceildiv(padded->extent, rhs)),
/* scale = */ padded->scale);
} else {
new_split = IterSplitExpr(IterMark(padded, padded->extent),
/* lower_factor = */ rhs,
Expand Down
34 changes: 34 additions & 0 deletions tests/python/unittest/test_arith_iter_affine_map.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1227,11 +1227,29 @@ def test_iter_map_simplify_unit_loop_order():


def assert_normalize_to_iter_sum(index, input_iters, args, base):
"""Assert the result of arith.normalize_to_iter_sum is correct

Parameters
----------
index : tvm.tir.PrimExpr
The index to be normalized
input_iters : Mapping[Var, Range]
The input iterators
args : List[Union[tvm.arith.IterSplitExpr, Tuple[PrimExpr, PrimExpr]]]
The expected result. Ordered list of args of the expected IterSumExpr. Each arg can be
either IterSplitExpr or a tuple of (PrimExpr, PrimExpr) where the first element is the
iterator normalized to PrimExpr and the second element is the scale.
base : tvm.tir.PrimExpr
The expected base
"""
res = tvm.arith.normalize_to_iter_sum(index, input_iters)

assert isinstance(res, tvm.arith.IterSumExpr)
assert len(res.args) == len(args)
for split, item in zip(res.args, args):
if isinstance(item, tvm.arith.IterSplitExpr):
tvm.ir.assert_structural_equal(split, item)
continue
tvm.testing.assert_prim_expr_equal(split.scale, item[1])
tvm.testing.assert_prim_expr_equal(
tvm.arith.normalize_iter_map_to_expr(split), item[0] * item[1]
Expand All @@ -1245,6 +1263,7 @@ def test_normalize_to_iter_sum():
z = tvm.tir.Var("z", "int64")
a = tvm.tir.Var("a", "int64")
n = tvm.tir.Var("n", "int64")
flm = tvm.tir.floormod

assert_normalize_to_iter_sum(
z + ((y + x * 4 + 2) * n) + 3,
Expand Down Expand Up @@ -1285,6 +1304,21 @@ def test_normalize_to_iter_sum():
0,
)

# non-divisible
assert_normalize_to_iter_sum(
x // 5,
var_dom([(x, 4096)]),
[
tvm.arith.IterSplitExpr(
tvm.arith.IterMark(x, 4096),
lower_factor=tvm.tir.const(5, "int64"),
extent=tvm.tir.const(820, "int64"),
scale=tvm.tir.const(1, "int64"),
)
],
0,
)

# iter simplify
assert_normalize_to_iter_sum(
z * 2 + 2 * y * 3 + 4 * (x // 4) + (x % 4),
Expand Down