Hzfengsy opened a new pull request, #18025: URL: https://github.com/apache/tvm/pull/18025
Fix a bug in canonical simplification of less-than expressions where the algorithm incorrectly assumed variables could have negative values when simplifying expressions of the form `ax + b < c`. The previous implementation checked if `-d < xn < d` before simplifying, but this was incorrect when variables are constrained to non-negative ranges. For example, with constraints `0 < x, y < 2` and expression `2x + y < 8`, the algorithm would incorrectly check if `-2 < y < 2` and then simplify to `x < 4`. However, when x=4 and y=-1, we get 2*4 + (-1) = 7 < 8, which satisfies the original constraint but violates the intended variable bounds. The fix changes the range check to `0 <= xn < d`, ensuring that simplification only occurs when variables are properly bounded from below at zero. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
