[XLA:GPU] Swap dot operands in certain cases. #19922
Open
+550
−0
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
![copybara-service[bot]](https://avatars.githubusercontent.com/in/44061?s=60&v=4){kind=small}
copybara-service
bot
force-pushed
the
test_699151018
branch
3 times, most recently
from
d970010
to
6334b08
Compare
On H100, the `wgmma` instruction supports lhs operand in registers but not rhs operand. That means that there is any prologue for one of the sides (e.g. conversion), it's better to put it into the lhs -- as elements will be in registers after computing the prologue. Additionally, minimal lhs non-contracting dimension size (M dimension) is 64, while for rhs smaller sizes are supported. Because of that, after the Triton fusion is known, swap lhs and rhs ops in the following cases: - If rhs has prologue, and lhs doesn't, and N-size (rhs non-contracting dim) is ≥64, swap. - If M<64 and N≥64, swap. PiperOrigin-RevId: 699151018
copybara-service
bot
force-pushed
the
test_699151018
branch
from
6334b08
to
046801c
Compare
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
[XLA:GPU] Swap dot operands in certain cases.
On H100, the
wgmmainstruction supports lhs operand in registers but not rhs operand. That means that there is any prologue for one of the sides (e.g. conversion), it's better to put it into the lhs -- as elements will be in registers after computing the prologue.Additionally, minimal lhs non-contracting dimension size (M dimension) is 64, while for rhs smaller sizes are supported.
Because of that, after the Triton fusion is known, swap lhs and rhs ops in the following cases: