(emit "~a:" exit-label)))
(define (data-tor env e)
- (and (list? e)
+ (if (not (list? e)) #f
(assoc (car e) (flat-map data-tors (env-data-layouts env)))))
+ ; returns the internal offset in bytes of a product within an ADT
+ ; given the constructor layout
+ ; constructor-layout: (foo (Int Bool))
+(define (data-product-offset data-layouts type sum index)
+ (let* ([products (cdr (assoc sum (cdr (assoc type data-layouts))))]
+ [to-traverse (list-head products index)])
+ (fold-left
+ (lambda (acc t) (+ acc (type-size data-layouts t)))
+ wordsize ; skip the tag in the first word
+ to-traverse)))
+
+(define (data-sum-tag data-layouts type sum)
+
+ (define (go acc sums)
+ (when (null? sums) (error #f "data-sum-tag no sum for type" sum type))
+ (if (eqv? sum (car sums))
+ acc
+ (go (+ 1 acc) (cdr sums))))
+ (let* ([type-sums (cdr (assoc type data-layouts))])
+ (go 0 (map car type-sums))))
+
(define (codegen-data-tor e si env)
(define (codegen-destructor tor)
- (when (not (eqv? 'stack (ast-type (cadr e))))
- (error #f "expected stack value"))
- (let* ([stack-expr (cadr e)]
- [stack-body (caddr stack-expr)]
- [stack-type (cadr stack-expr)])
-
- (codegen-expr stack-body si env)
- (let ([index (cadr tor)]
- [products 2]
- [to-traverse (list-head products index)]
- [offset (fold-left
- (lambda (acc t) (+ acc (type-size t)))
- wordsize ; skip tag in first word
- to-traverse)])
- 3
- )))
+ (let* ([res (codegen-expr (cadr e) si env)]
+ [info (cadr tor)]
+ [index (caddr info)]
+ [type (car info)]
+ [sum (cadr info)])
+ (when (not (stack-expr? res))
+ (error #f "codegened something that wasn't a stack expression"))
+ ;TODO handle stack types
+ (emit "movq ~a(%rbp), %rax"
+ (- si (data-product-offset (env-data-layouts env) type sum index)))))
+
+ (define (codegen-constructor tor)
+ (let* ([info (cadr tor)]
+ [type (car info)]
+ [sum (cadr info)]
+ [constructor (car e)]
+
+ [args (cdr e)]
+
+ [tag (data-sum-tag (env-data-layouts env)
+ type
+ sum)]
+
+ [insert-product
+ (lambda (expr i)
+ (let ([res (codegen-expr expr si env)]
+ [stack-offset (- si (data-product-offset (env-data-layouts env)
+ type sum
+ i))])
+ (if (stack-expr? res)
+ (error #f "todo: handle stack-exprs in stack exprs")
+ (emit "movq %rax, ~a(%rbp)" stack-offset))))])
+
+ ; emit the tag
+ (emit "movq $~a, ~a(%rbp)" tag si)
+
+ (for-each insert-product args (range 0 (length args)))
+ (type-size (env-data-layouts env) type)))
(let* ([tor (data-tor env e)]
- [constructor (eqv? 'constructor (cadr tor))])
+ [constructor (eqv? 'constructor (caddr (cadr tor)))])
(if constructor
(codegen-constructor tor)
(codegen-destructor tor))))
+(define stack-expr? number?)
+
+ ; returns a number if result was stored on stack
(define (codegen-expr e si env)
(emit "# ~a" e)
(case (ast-type e)
('static-string (emit "movq ~a@GOTPCREL(%rip), %rax"
(cadr e)))
- ('stack (error #f "stack value that needs explicit handling" e))
+ ('stack (codegen-expr (caddr e) si env))
(else (error #f "don't know how to codegen this"))))
(set! cur-lambda 0)
(let* ([data-layouts (program-data-layouts program)]
- [type-annotated (annotate-types program)]
+ [pattern-matched (expand-pattern-matches program)]
+ [type-annotated (annotate-types pattern-matched)]
[stack-annotated (annotate-stack-values data-layouts
type-annotated)]