1. Optimize if statements (parity with OG compiler):
- discard empty 'alternative' blocks
- optimize to the consequent if the predicate is a nonzero integer
- optimize to the alternative, or an empty block if there is none, if the predicate is a zero integer.
2. In comparison mode, emit module functions in the same order as the OG compiler.
This is because the OG compiler can emit declarations for module functions that it doesn't actually call, and in a different order than calls to actual module functions.
Adds:
- ast/UserFunction AST node for user-defined functions.
- astbuilder/AvailableUserFunction: reference to a parse tree for a user function.
- The AST builder only generates ASTs for user functions that are actually referenced.
- astbuilder/UserFunctionVisitor: visits (builds an AST for) a parse tree for a user function.
- This happens after the .src or .inc file has been otherwise processed, so this class serves to hook up the correct SourceFileIdentifier to the AST.
Add astbuilder/BuilderWorkspace:
- Temporary workspace used while building the AST (which goes in the CompilerWorkspace)
Add astbuilder/CompilerWorkspaceBuilder:
- Builds a CompilerWorkspace for a script
Add model/CompilerWorkspace:
- Holds AST
- Holds some intermediate data used by semantic analyzer, optimizer, code generator
