MSL does not support value semantics for arrays (sigh), so we need to
force constant references and deal with copies if we have a different
address space than what we end up guessing.
Add CompilerMSL::Options::texture_width_max.
Emit and use spvTexelBufferCoord() function to convert 1D
texel buffer coordinates to 2D Metal texture coordinates.
Certain patterns with OpVectorShuffle (and probably others) will cascade
to so large, that they can cause OOM. After we have observed
force_recompile, don't spend unnecessary memory emitting code which will
never be used.
