BranchInliner is too aggressive for ternaries

[fehnomenal]

Running

function ao1(s)
    return s == "" and 1 or 2
end

function ao2(b)
    return b and 1 or 2
end

function ao3()
    return true and 1 or 2
end

function ao4()
    return false and 1 or 2
end

r1 = ao1("")
r2 = ao1("a")
r3 = ao2(true)
r4 = ao2(false)
r5 = ao3()
r6 = ao4()

results in the following

env.rawget("r1") = 1
env.rawget("r2") = false
env.rawget("r3") = 1
env.rawget("r4") = 2
env.rawget("r5") = 1
env.rawget("r6") = false

where I would expect (see also on https://www.lua.org/cgi-bin/demo)

env.rawget("r1") = 1
env.rawget("r2") = 2
env.rawget("r3") = 1
env.rawget("r4") = 2
env.rawget("r5") = 1
env.rawget("r6") = 2

This is exactly the result I get when I remove the call to the BranchInliner in the optimize method for IRFuncs.