[perl #22359] IMCC Optimizer fails with various types of hand-rolled loops

[Clinton A. Pierce]

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The IMCC optimizer run with these options:

        ..\..\imcc\imcc -Op1 -d60 err.imc

Bug #1:
Issues the error message (now a warning, but probably a problem nontheless):

        error:imcc:sort_loops: loop 1 contains first but notlast of outer loop 0

A sample to cause this problem is:

.sub _main
         .local int count
         set count, 2
KEYLOOP:le count, 0, BAIL
         eq count, 2, TWO
         eq count, 1, ONE
         end
TWO:    dec count
         branch KEYLOOP
ONE:    dec count
         branch KEYLOOP
BAIL:  print "Hello"
        end
.end

Bug #2
Run with the same options, and slightly simplified code, this error message 
is emitted:

        if_branch eq ... ONE
        error:imcc:iANY file err.imc line 12: op not found 'ne_i_ic' (ne<3>)

A sample to cause this problem is:

.sub _main
         .local int count
         set count, 1
KEYLOOP:le count, 0, BAIL
         eq count, 1, ONE
         end
ONE:    dec count
         branch KEYLOOP
BAIL:   print "Hello"
         end
.end

Running either sample without the optimizer produces the expected results.