Assertion "attempted to pop a value from an empty stack" compiling with dynamic 0-sized memories

[alexcrichton]

This module:

(module
  (func
    i32.const 0
    v128.load32_splat
    drop
  )
  (memory 0 0)
)

currently panics on main with:

$ cargo run compile testcase0.shrunken.wat --static-memory-maximum-size 0
    Finished dev [unoptimized + debuginfo] target(s) in 0.12s
     Running `target/debug/wasmtime compile testcase0.shrunken.wat --static-memory-maximum-size 0`
thread '<unnamed>' panicked at 'attempted to pop a value from an empty stack', cranelift/wasm/src/state.rs:309:14
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

Bisection points to #5386, so cc @fitzgen

[fitzgen]

Looking into this.