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Diffstat (limited to 'lib/csc/ir2.csc')
| -rw-r--r-- | lib/csc/ir2.csc | 217 |
1 files changed, 217 insertions, 0 deletions
diff --git a/lib/csc/ir2.csc b/lib/csc/ir2.csc new file mode 100644 index 0000000..888437f --- /dev/null +++ b/lib/csc/ir2.csc @@ -0,0 +1,217 @@ +(define-library (csc ir2) + (export + %apply + %branch + %closure + %fix + %globals + %label + %primitive + %tail + %variable + *globals* + *tail* + apply-arguments + apply-procedure + apply? + branch-atom + branch-false + branch-true + branch? + call-closure-args + call-closure-closure + call-closure? + closure-arguments + closure-body + closure-name + closure-rest + closure? + fix-body + fix-functions + fix? + globals? + label-gensym + label? + make-apply + make-branch + make-call-closure + make-closure + make-fix + make-label + make-primitive + make-variable + primitive-arguments + primitive-continuation + primitive-operation + primitive-results + primitive? + tail? + variable-gensym + variable? + + ; Re-exports from IR1. + %constant + %library-ref + constant-expression + constant? + lexical-ref-gensym + lexical-ref-name + lexical-ref? + lexical-set-expression + lexical-set-ref + lexical-set? + library-ref-library + library-ref-name + library-ref? + make-constant + make-lexical-ref + make-lexical-set + make-library-ref) + (import (scheme base) + (only (csc ir1) + %constant + %library-ref + constant-expression + constant? + lexical-ref-gensym + lexical-ref-name + lexical-ref? + lexical-set-expression + lexical-set-ref + lexical-set? + library-ref-library + library-ref-name + library-ref? + make-constant + make-lexical-ref + make-lexical-set + make-library-ref) + (only (csc list) all) + (only (csc loop) + loop + return) + (only (csc match) + define-match-record-type + match)) + (begin + ; This library defines the intermediate representation IR2. + ; It's CPS time bitch. + + ; CPS atom: + ; An atom is a value that can be computed immediately without + ; any subexpressions. + ; Atoms consist of + ; - constant, + ; - lexical-ref, + ; - library-ref, + ; - or globals. + ; After closure conversion, there are no more lexical refs. + ; Each lexical ref will be converted to a <variable>. + + + ; A function argument or local variable. + (define-match-record-type <variable> + (make-variable gensym) + variable? + %variable + (gensym variable-gensym)) + + + ; The globals array. This will eventually be stored in register 0. + (define-match-record-type <globals> + (make-globals) + globals? + %globals) + + + ; A global instance of <globals>. + ; Considered equal to calling (make-globals). + (define *globals* (make-globals)) + + + ; A label, used for function names and will compile to a constant. + (define-match-record-type <label> + (make-label gensym) + label? + %label + (gensym label-gensym)) + + + ; CPS expressions: + ; CPS expressions are similar to IR1 expressions, + ; but constrained not to have any subexpressions except atoms. + ; And they take a continuation. + + + ; A primitive encodes one of a number of primitive operations. + ; Each operation takes a number of arguments, + ; and binds some number of result variables. + ; The known primitives are listed below, along with their arity. + ; - alloc: size -> result + ; - peek: pointer * offset -> result + ; - poke: word * pointer * offset -> () + ; - exit: code -> () + (define-match-record-type <primitive> + (make-primitive operation arguments results continuation) + primitive? + %primitive + (operation primitive-operation) + (arguments primitive-arguments) + (results primitive-results) + (continuation primitive-continuation)) + + + ; Branches depending on the given atom. + ; If it is true, continue with continuation true. + ; If false, continue with continuation false. + (define-match-record-type <branch> + (make-branch atom true false) + branch? + %branch + (atom branch-atom) + (true branch-true) + (false branch-false)) + + + ; Applies a procedure to a list of arguments. Apply does not take a + ; continuation. Instead the continuation will be passed as the first + ; argument to the function. + (define-match-record-type <apply> + (make-apply procedure arguments) + apply? + %apply + (procedure apply-procedure) + (arguments apply-arguments)) + + + ; The tail continuation. Used for the exit point of library init functions, + ; and the end of a program. + (define-match-record-type <tail> + (make-tail) + tail? + %tail) + + + (define *tail* (make-tail)) + + + ; A procedure. All closures are allocated in a fix expression. A closure + ; does not take a continuation. Instead, the procedure will accept the + ; continuation as an argument. + (define-match-record-type <closure> + (make-closure name arguments body) + closure? + %closure + (name closure-name) + (arguments closure-arguments) + (body closure-body)) + + + ; Defines a list of mutually recursive procedures. + ; Functions is a list of closures, and body is an expression. + (define-match-record-type <fix> + (make-fix functions body) + fix? + %fix + (functions fix-functions) + (body fix-body)))) |