Fix tl.rand range assertion: [0, 1) not [0, 1]#9966
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tl.rand returns values in the half-open interval [0, 1), not the closed interval [0, 1]. The test assertion used x <= 1, which would have accepted 1.0 as a valid output. Philox-based float generation masks the upper mantissa bits and sets the exponent to produce values strictly less than 1.0. A value of exactly 1.0 indicates a bug (e.g. broken seed delivery returning all-ones from the uint-to-float conversion).
Jokeren
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plognjen
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tl.rand returns values in the half-open interval [0, 1), not the closed interval [0, 1]. The test assertion used x <= 1, which would have accepted 1.0 as a valid output. Philox-based float generation masks the upper mantissa bits and sets the exponent to produce values strictly less than 1.0. A value of exactly 1.0 indicates a bug (e.g. broken seed delivery returning all-ones from the uint-to-float conversion). <!--- The core Triton is a small number of people, and we receive many PRs (thank you!). To help us review your code more quickly, **if you are a new contributor (less than 3 PRs merged) we ask that you complete the following tasks and include the filled-out checklist in your PR description.** Complete the following tasks before sending your PR, and replace `[ ]` with `[x]` to indicate you have done them. --> # New contributor declaration - [x] I am not making a trivial change, such as fixing a typo in a comment. - [x] I have written a PR description following these [rules](https://cbea.ms/git-commit/#why-not-how). - [x] I have run `pre-commit run --from-ref origin/main --to-ref HEAD`. - Select one of the following. - [ ] I have added tests. - `/test` for `lit` tests - `/unittest` for C++ tests - `/python/test` for end-to-end tests - [x] This PR does not need a test because it's fixing a test. - Select one of the following. - [x] I have not added any `lit` tests. - [ ] The `lit` tests I have added follow these [best practices](https://mlir.llvm.org/getting_started/TestingGuide/#filecheck-best-practices), including the "tests should be minimal" section. (Usually running Python code and using the instructions it generates is not minimal.) Co-authored-by: Wes Turner <westurner@users.noreply.github.com>
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tl.rand returns values in the half-open interval [0, 1), not the closed interval [0, 1]. The test assertion used x <= 1, which would have accepted 1.0 as a valid output.
Philox-based float generation masks the upper mantissa bits and sets the exponent to produce values strictly less than 1.0. A value of exactly 1.0 indicates a bug (e.g. broken seed delivery returning all-ones from the uint-to-float conversion).
New contributor declaration
I am not making a trivial change, such as fixing a typo in a comment.
I have written a PR description following these
rules.
I have run
pre-commit run --from-ref origin/main --to-ref HEAD.Select one of the following.
/testforlittests/unittestfor C++ tests/python/testfor end-to-end testsSelect one of the following.
littests.littests I have added follow these best practices,including the "tests should be minimal" section. (Usually running Python code
and using the instructions it generates is not minimal.)