Function drutil_opnd_mem_size_in_bytes 

pub unsafe extern "C" fn drutil_opnd_mem_size_in_bytes(
    memref: opnd_t,
    inst: *mut instr_t,
) -> uint

Returns the size of the memory reference \p memref in bytes. To handle OP_enter, requires the containing instruction \p inst to be passed in. For single-instruction string loops, returns the size referenced by each iteration.

If the instruction is part of the xsave family of instructions, this returns an incomplete computation of the xsave instruction’s written xsave area’s size. Specifically, it

• Ignores the user state mask components set in edx:eax, because they are dynamic values. The real output size of xsave depends on the instruction’s user state mask AND the user state mask as supported by the CPU based on the XCR0 control register.
• Ignores supervisor state component PT (enabled/disabled by user state component mask bit 8).
• Ignores the user state component PKRU state (enabled/disabled by user state component mask bit 9).
• Ignores the xsaveopt flavor of xsave.
• Ignores the xsavec flavor of xsave (compacted format).

It computes the expected size for the standard format of the x87 user state component (enabled/disabled by user state component mask bit 0), the SSE user state component (bit 1), the AVX user state component (bit 2), the MPX user state components (bit 2 and 3) and the AVX-512 user state component (bit 7).