X-Git-Url: https://git.lukelau.me/?a=blobdiff_plain;f=codegen.scm;h=b90e7cdcefff689f56ce3b9cb911de408949b872;hb=190fc656a7b4e12e6fcf640c56e6ff71b5a39e40;hp=2d5f4ac2731800dba6e4041162bc7693be62f90a;hpb=89ef32141732e6d0bbfc7484b465844b62d8d139;p=scheme.git

diff --git a/codegen.scm b/codegen.scm
index 2d5f4ac..b90e7cd 100644
--- a/codegen.scm
+++ b/codegen.scm
@@ -11,12 +11,12 @@
 
 (define wordsize 8)
 
-(define (type-size type env)
+(define (type-size data-layouts type)
 
   (define (adt-size adt)
     (let ([sizes
 	   (map (lambda (sum)
-		  (fold-left (lambda (acc x) (+ acc (type-size x)))
+		  (fold-left (lambda (acc x) (+ acc (type-size data-layouts x)))
 			     wordsize ; one word needed to store tag
 			     (cdr sum)))
 		(cdr adt))])
@@ -26,16 +26,21 @@
     ['Int wordsize]
     ['Bool wordsize]
     [else
-     (let ([adt (assoc type (env-adts env))])
+     (let ([adt (assoc type data-layouts)])
        (if adt
 	   (adt-size adt)
 	   (error #f "unknown size" type)))]))
 
+(define (on-stack? expr)
+  (case (ast-type expr)
+    ['stack (cadr expr)]
+    [else #f]))
+
 					; an environment consists of adt layouts in scope,
 					; and any bound variables.
 					; bound variables are an assoc list with their stack offset
 (define make-env list)
-(define env-adts car)
+(define env-data-layouts car)
 (define env-bindings cadr)
 
 (define (codegen-add xs si env)
@@ -160,7 +165,7 @@
 			      acc))
 		      (env-bindings env)
 		      comps)]
-		    [scc-env (make-env (env-adts env) scc-binding-offsets)])
+		    [scc-env (make-env (env-data-layouts env) scc-binding-offsets)])
 	       (for-each 
 		(lambda (name)
 		  (let ([expr (cadr (assoc name bindings))])
@@ -171,7 +176,7 @@
 			(codegen-expr expr
 				      inner-si
 				      (make-env
-				       (env-adts scc-env)
+				       (env-data-layouts scc-env)
 				       (cons (cons name 'self-captive)
 					     (env-bindings scc-env))))
 			(codegen-expr expr inner-si scc-env))
@@ -359,12 +364,18 @@
 
 (define (data-tor env e)
   (and (list? e)
-       (assoc (car e) (flat-map data-tors (env-adts env)))))
+       (assoc (car e) (flat-map data-tors (env-data-layouts env)))))
 
 (define (codegen-data-tor e si env)
 
   (define (codegen-destructor tor)
-    (codegen-expr (cadr e) si env)
+    (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)]
@@ -373,9 +384,9 @@
 		   wordsize ; skip tag in first word
 		   to-traverse)])
       3
-      ))
+      )))
   
-  (let ([tor (data-tor env e)]
+  (let* ([tor (data-tor env e)]
 	 [constructor (eqv? 'constructor (cadr tor))])
     (if constructor
 	(codegen-constructor tor)
@@ -400,7 +411,8 @@
 	    (codegen-call (car e) (cdr e) si env)))))
 
 					; this is a builtin being passed around as a variable
-    ('builtin (emit "movq $~a, %rax" (builtin-id e)))
+					; this should have been converted to a closure!
+    ('builtin (error #f "passing about a builtin!" e))
 
     ('let (codegen-let (let-bindings e)
 		       (let-body e)
@@ -417,9 +429,24 @@
     ('static-string (emit "movq ~a@GOTPCREL(%rip), %rax"
 			  (cadr e)))
 
-    (else (error #f "don't know how to codegen this"))))
+    ('stack (error #f "stack value that needs explicit handling" e))
 
+    (else (error #f "don't know how to codegen this"))))
 
+					; takes in a expr annotated with types and returns a type-less AST
+					; with stack values wrapped
+(define (annotate-stack-values data-layout ann-e)
+  (define (stack-type? type)
+    (assoc type data-layout))
+  (define (strip e)
+    (ast-traverse strip (ann-expr e)))
+  (let* ([e (ann-expr ann-e)]
+	 [type (ann-type ann-e)])
+    (if (stack-type? type)
+	`(stack ,type ,(ast-traverse strip e))
+	(ast-traverse (lambda (x)
+			(annotate-stack-values data-layout x))
+		      e))))
 
 (define (free-vars prog)
   (define bound '())
@@ -583,15 +610,17 @@
 (define (codegen program)
   (set! cur-label 0)
   (set! cur-lambda 0)
-  (let* ([body (program-body program)]
+  (let* ([data-layouts (program-data-layouts program)]
 
-	 [data-layouts (map data-layout (program-datas program))]
+	 [type-annotated (annotate-types program)]
+	 [stack-annotated (annotate-stack-values data-layouts
+						 type-annotated)]
 	 
-	 (extract-res-0 (extract-strings body))
-	 (strings (car extract-res-0))
-	 (extract-res-1 (extract-lambdas (cdr extract-res-0)))
-	 (lambdas (car extract-res-1))
-	 (xform-prog (cdr extract-res-1)))
+	 (strings-res (extract-strings stack-annotated))
+	 (strings (car strings-res))
+	 (lambdas-res (extract-lambdas (cdr strings-res)))
+	 (lambdas (car lambdas-res))
+	 (xform-prog (cdr lambdas-res)))
 
     (emit "\t.global _start")
     (emit "\t.text")
@@ -647,6 +676,6 @@
 ; %r8  = 5th arg
 ; %r9  = 6th arg
 
-; on darwin, the syscall is offset by 0x2000000
+; on darwin, unix/posix syscalls are offset by 0x2000000 (syscall classes)
 ; https://opensource.apple.com/source/xnu/xnu-2782.20.48/bsd/kern/syscalls.master
 ; documentation for most syscalls: /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/sys