* src/SDCCcse.c (algebraicOpts): fix bug converting op from value to type

* src/SDCCcse.c (algebraicOpts): fix bug converting op from value to type
* src/SDCCicode.c (operandOperation): rewritten some ops (*, ==, unary_minus) to fix possible overflows and to accord with ANSI
* src/SDCCsymt.c (computeType): literals are handled the same way as any other type
* src/SDCCval.c (cheapestVal): removed, it doesn't accord with ANSI (can be re-activated by defining REDUCE_LITERALS)
* src/SDCCval.c (constVal): fixed; hex and octal constants can be unsigned, but are signed by default
* src/SDCCval.c (constVal): rearranged
* src/SDCCval.c (valMod): preliminary fix
* src/SDCCval.c (valCastLiteral): use TYPE_* types
* support/regression/literalop.c: added, work in progress

git-svn-id: https://sdcc.svn.sourceforge.net/svnroot/sdcc/trunk/sdcc@2825 4a8a32a2-be11-0410-ad9d-d568d2c75423