Pywebassembly

[lrettig]

Native python ewasm interpreter

child of #32

[lrettig]

@poemm's update from today's standup: All tests are passing except memgrow/memsize (which WABT doesn't support) and floating point (which he hasn't implemented yet). He's now going to start implementing the EEI for pywebassembly 👏

[lrettig]

@poemm update today: all (non-float) assert_return tests pass including memory.grow and memory.size. wrote PyEEI infrastructure, didn’t implement functions yet. next step is to read up on EVM design in py-evm/trinity.

[lrettig]

@poemm update from yesterday: all assert_trap tests pass (except those involving floating point numbers), pushed test infrastructure

[lrettig]

@poemm update from this morning:

• Overhauled PyWebAssembly byte/little-endian encoding for i32,i64,f32,f64; now supports floating point using Python float type
• passing floating point tests, except don’t know how to modify NaN’s significand like spec says, this is deprioritized for now, later will consider numpy.float32/64, decimal, or ctypes.c_float/c_double
• also deprioritizing malformed, valid, linking tests since the sentinel may do these