[llvm] [DAG] SDPatternMatch - Replace runtime data structures with lengths known at compile time (PR #172064)

[Simon Pilgrim via llvm-commits]

RKSimon wrote:

Both are intermittent failures on more "exotic" buildbots - the trick is to check if they go green again the following build without a relevant commit fix :) 

https://github.com/llvm/llvm-project/pull/172064