forked from tinygrad/tinygrad
same as #7009 but for logsumexp and logcumsumexp. fwd+bwd kernel count 5 -> 3 for both. gradients unchanged (ties, -inf masks, torch-compared at grad_atol=1e-7).
Three groups of tests run in CI backend -- tests that run on each backend null -- tests that don't require any backend unit -- tests that only run on a single backend in CI