Document wasm-interp trace output

[jiayihu]

Is there any documentation on how to read the wasm-interp trace output? I can intuitively understand some of it, but most of the output is ambigous to me. For instance I was debugging an issue:

>>> running export "bench":
#0.    0: V:0  | alloca 4
#0.    8: V:4  | global.get $0
#0.   16: V:5  | i32.const 32
#0.   24: V:6  | i32.sub 16, 32
#0.   28: V:5  | local.set $5, 4294967280
#0.   36: V:4  | i32.const 0
#0.   44: V:5  | local.set $4, 0
#0.   52: V:4  | local.get $3
#0.   60: V:5  | i32.const 4
#0.   68: V:6  | i32.eq 0, 4
#0.   72: V:5  | br_unless @88, 0
#0.   88: V:4  | local.get $4
#0.   96: V:5  | i32.const 28
#0.  104: V:6  | i32.add 4294967280, 28
#0.  108: V:5  | local.get $4
#0.  116: V:6  | i32.add 12, 0
#0.  120: V:5  | i32.const 0
#0.  128: V:6  | i32.store $0:12+$0, 0
#0.  140: V:4  | local.get $3
#0.  148: V:5  | i32.const 4
#0.  156: V:6  | i32.add 0, 4
#0.  160: V:5  | local.set $4, 4
#0.  168: V:4  | br @52
#0.   52: V:4  | local.get $3
#0.   60: V:5  | i32.const 4
#0.   68: V:6  | i32.eq 4, 4
#0.   72: V:5  | br_unless @88, 1
#0.   80: V:4  | br @176
#0.  176: V:4  | i32.const 0
#0.  184: V:5  | local.set $4, 0
#0.  192: V:4  | local.get $4
#0.  200: V:5  | i32.load $0:4294967280+$28
bench() => error: out of bounds memory access: access at 4294967308+4 >= max value 65536

I don't know what the first value #0 is, or what the second column values (0, 8, 16...) are, what V:5 stays for and so on. I can imagine it is obvious for most of you who closely work on Wasm compilers/interpreters, but for a non-expert a little help would be valuable.

My guess would be that the first column is the call stack depth maybe? The column column is the value stack size, the V: x is the value at the top of the value stack depth, and then finally the instruction where the implicit operands taken from the top of the stack are made explicit.