tqchen commented on code in PR #11646: URL: https://github.com/apache/tvm/pull/11646#discussion_r894708382
########## src/arith/const_int_bound.cc: ########## @@ -341,6 +343,18 @@ class ConstIntBoundAnalyzer::Impl } } + Entry VisitLeftShift(const CallNode* op) { + Entry a = VisitExpr(op->args[0]); + Entry b = VisitExpr(op->args[1]); + + // Until C++20, performing a left shift is only well-defined for + // positive arguments. If we have a negative argument, it just + // means we couldn't prove that the inputs were positive. + a.min_value = std::max(int64_t(0), a.min_value); + b.min_value = std::max(int64_t(0), b.min_value); + return BinaryOpBoundary(a, b, InfAwareLeftShift); Review Comment: Given simplification logic like this one are used everywhere, it does merit an extra care. Specialization might make sense to be on the safe side. -- 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: commits-unsubscr...@tvm.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org