Actually... perl5 creates an opcode tree directly from the perl source. You can peek at it by using such nifty tools as B::Concise. Bytecode is a serialization of an opcode tree but is not normally invoked by perl. The only time you deal with bytecode is when you want to save a compiled opcode tree out to disk.

Opcode trees are just a bunch of C structs hanging around in memory and pointing to each other. perl executes by following the links between each node and running routines along the way. I've accumulated some references to the opcode tree around and can post them if you're interested.

__SIG__
use B;
printf "You are here %08x\n", unpack "L!", unpack "P4", pack
  "L!", B::svref_2object(sub{})->OUTSIDE;
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