MemoryInstruction

Base class for all Instructions dealing with memory.

From

Instructions in this group are concerned with linear memory.

Memory is accessed with load and store instructions for the different value types. They all take a memory immediate MemArg that contains an address offset and the expected alignment (expressed as the exponent of a power of 2). Integer loads and stores can optionally specify a storage size that is smaller than the bit width of the respective value type. In the case of loads, a sign extension mode sx is then required to select appropriate behavior.

The static address offset is added to the dynamic address operand, yielding a 33 bit effective address that is the zero-based index at which the memory is accessed. All values are read and written in little endian byte order. A trap results if any of the accessed memory bytes lies outside the address range implied by the memory’s current size.

instr  ::= inn.load memarg
           fnn.load memarg
           inn.store memarg
           fnn.store memarg
           inn.load8_sx memarg
           inn.load16_sx memarg
           i64.load32_sx memarg
           inn.store8 memarg
           inn.store16 memarg
           i64.store32 memarg
           memory.size
           memory.grow