Semantic Analysis: Difference between revisions
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This version has been improved to perform type checking in the C generator visitor. This visitor uses a second visitor to check types before deciding on which code to generate. The checks are related with the use of boolean expressions in tests (while, if, and if-else nodes) and with type consistency in operators (in this case, although we could have decided otherwise, operators such as + and - must have arguments of the same type and this type must be integer). In addition, the compiler now checks if a variable has the proper type in certain cases (for instance, in the tests mentioned above). | This version has been improved to perform type checking in the C generator visitor. This visitor uses a second visitor to check types before deciding on which code to generate. The checks are related with the use of boolean expressions in tests (while, if, and if-else nodes) and with type consistency in operators (in this case, although we could have decided otherwise, operators such as + and - must have arguments of the same type and this type must be integer). In addition, the compiler now checks if a variable has the proper type in certain cases (for instance, in the tests mentioned above). | ||
* [http://www.l2f.inesc-id.pt/~david/ist/docencia/compiladores/2007-2008/compact-with-simple-type-checking-200805111819.tar.bz2 Compact with simple type checking (200805111819)] | |||
== Simple Type Checking Example == | == Simple Type Checking Example == | ||
Revision as of 17:21, 11 May 2008
- Abstract syntax tree; nodes
- Symbols and types
- Symbol table
- Varible and function declarations
- Type checking
Type Checking Example: Compact
The package provided here contains the Compact compiler.
This version has been improved to perform type checking in the C generator visitor. This visitor uses a second visitor to check types before deciding on which code to generate. The checks are related with the use of boolean expressions in tests (while, if, and if-else nodes) and with type consistency in operators (in this case, although we could have decided otherwise, operators such as + and - must have arguments of the same type and this type must be integer). In addition, the compiler now checks if a variable has the proper type in certain cases (for instance, in the tests mentioned above).
Simple Type Checking Example
The following example considers a simple grammar and performs the whole of the semantic analysis process and, finally, generates the corresponding C code. The semantic analysis process must account for variables (they must be declared before they can be used) and for their types (all types must be used correctly).