- use array variables instead of pointers
- add const where possible
- use enums to assign values for high getopt options insteaf of
  possibly error-prone manual assignment.  Also documents the
  code better

- use array variables instead of pointers
- add const where possible
- use enums to assign values for high getopt options insteaf of
  possibly error-prone manual assignment.  Also documents the
  code better

jl_egal is an exported and recursively called function which puts
some constraints on the optimizer.  The way jl_egal is currently
structured it pretty much as all the code needed for the comparisons
inlined, including the more complex parts to compare tuples and
fields.  The code goes to great length to optimize special cases
which can be treated simpler but the generalization of the rest of
the code causes problems.

Specifically, the more complex parts of the comparison process require
more registers for the optimized code to use.  The results in the
function starting with a large prologue which saves all the callee-save
registers that are used, followed in the end by the respective epilogue.

This means that even though in some cases the function will almost
immediately return because of the special case handling, all the work
for of the prologue and epilogue still has to be done.

I ran limited profiling (mostly the arrayops test case) and the jl_egal
function shows up on position 3 with 5.48%.  With the simple change in
this patch this is reduced to 4.64%.

The patch is trivial, no real code changes.  To prevent the complex
prologue/epilogue from unconditionally bing created the complex code
blocks are moved into their own functions and then these functions are
called.  To prevent the optimizer from negating this work the functions
must be marked appropriately.  Fortunately I've found that this is
already done in some cases elsewhere in the code base so I'm sure the
change will not create any problem.

- introduce macros NOINLINE and NOINLINE_DECL
- adjust existing code in task.c
- rewrite change for jl_egal using NOINLINE
- add extensive comment explaining jl_egal change