Major changes to HuCC's comparison code-generation. #50
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…st to set the flags for branching, and the second to convert the flag into a boolean int that can be stored or used in math. This allows the second stage I_BOOLEAN i-code to be removed by the peephole if an integer value is not needed/used. At the moment this just saves one CLY instruction for most tests, but it could be more if the test results return the C flag instead of the Z flag as true or false.
…ments for the local name rather than the `;` style. Seperate the /* */ comment a bit further away from the compiler-generated name so that it is a bit easier to read.
correct the VPC initialization comments in vdc.asm
Uli's attempt to generate byte comparisons has been completely removed from the code-generation section of the compiler because the SmallC expression code does not propagate operand size information. Remove the last of the T_LIB usage of embedded comparison name strings, and use integer enums instead which make it easier to optimize comparison-ops. Teach the peephole optimizer how to convert the compare-with-integer operations into a new i-code that generates faster inline code. Further optimize unsigned char compare-with-integer operations when they can be detected.
…memory and compare-with-stack operations into new i-codes that generate faster inline code.
…ng A and the Z flag. This makes most of the common comparison operations a little quicker with the cost that the rare boolean conversion step is slower and larger when it isn't removed by the peephole optimizer. The most common boolean is "var = !var", and this can be optimized separately in the future.
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These save more time than space, but even then the improvement isn't going to be great.
OTOH, having more comparisons look like something that an asm programmer would write is a positive from my POV.