There are a few different performance issues with the Java bytecode verifier. Are you referring to this one? https://pdfs.semanticscholar.org/7dd2/b5359ab507fe

There are a few different performance issues with the Java bytecode verifier. Are you referring to this one? https://pdfs.semanticscholar.org/7dd2/b5359ab507fec1b1223db6edf5f58f9a28b6.pdf https://pdfs.semanticscholar.org/7dd2/b5359ab507fec1b1223db6... The cause of this is that the dataflow analysis performs nontrivial merging of dataflow facts, requiring a reanalysis. In the WebAssembly design there is no merging; any divergence of stack effects is an error. There are other deeper issues with the Java design: bytecode subroutines, the fact that the Java subtype relation doesn't form a semilattice, and way in which Java bytecode models object initialization.