beam_type: Enhance coalescing of allocation instructions

An 'allocate' or 'allocate_zero' instruction should not be
shortly followed by a 'test_heap' instruction. For example,
we don't want this type of code:

    {allocate_zero,3,4}.
    {line,...}.
    {test_heap,7,4}.
    {bif,element,{f,0},...,...}.

While the code is safe because 'allocate_zero' has initialized the
stack frame, it is wasteful. Also note that the code would become
unsafe if the 'allocate_zero' instruction were to be replaced with
an 'allocate' instruction.

What we want to see is this:

    {allocate_heap_zero,3,7,4}.
    {line,...}.
    {bif,element,{f,0},...,...}.

0 files changed, 0 insertions, 0 deletions