\brief Provide the caller with an emitter for building the p-code snippet Any p-code produced by the PcodeEmit, when triggered by the caller, becomes part of the \e snippet that will get emulated by \b this. The caller should free the PcodeEmit object immediately after use. \param inst is the \e opcode to \e behavior map the emitter will use \param uniqReserve is the starting offset within the \e
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