if (shouldSpeculateInteger(node.child1()) && !isStrictInt32(node.child1())), the JSVALUE64 JIT will currently compare all 64bits in the register, but in these cases the DataFormat is always a JS boxed integer. In these cases we can just compare the low 32bits anyway - no need to check the tag. This allows the code to be unified with the JSVALUE32_64 JIT.
Created attachment 109354 [details] The patch
Fixed in r96436