Always false stack checks are not eliminated - fix on the way

[Jan Stolarek]

Hi guys,

I accidentally introduced a bug in one of my recent commits ( 
94125c97e49987e91fa54da6c86bc6d17417f5cf): stack checks of the form 

if (Sp < SpLim) goto cUP; else goto cUQ;

are not eliminated in the Cmm. I have a fix, but need to validate it and update the comments. It 
will be ready tomorrow.

Janek