From e51b9e423665428c41cddac0642d1e34b18ca1da Mon Sep 17 00:00:00 2001
From: Luke Lau <luke_lau@icloud.com>
Date: Mon, 22 Jul 2019 02:37:02 +0100
Subject: [PATCH] Fix some normalization issues, add codegen tests

---
 codegen.scm   |  6 ++++--
 tests.scm     | 26 ++++++++++++++++++++++++++
 typecheck.scm |  9 ++++++---
 3 files changed, 36 insertions(+), 5 deletions(-)

diff --git a/codegen.scm b/codegen.scm
index 04816ab..d30adc5 100644
--- a/codegen.scm
+++ b/codegen.scm
@@ -59,6 +59,8 @@
   (for-each (lambda (form) (codegen-expr form inner-si inner-env)) body)))
 
 (define (codegen-var name si env)
+  (when (not (assoc name env))
+    (error #f (format "Variable ~a is not bound" name)))
   (let ((offset (cdr (assoc name env))))
     (emit "movq ~a(%rsp), %rax" offset)))
 
@@ -259,10 +261,10 @@
     (amd64-abi
      (lambda () (codegen-expr xform-prog 0 '())))))
 
-(define (compile-to-binary program)
+(define (compile-to-binary program output)
   (when (not (eq? (typecheck program) 'int)) (error #f "not an int"))
   (let ([tmp-path "/tmp/a.s"])
     (when (file-exists? tmp-path) (delete-file tmp-path))
     (with-output-to-file tmp-path
       (lambda () (codegen program)))
-    (system "clang -fomit-frame-pointer /tmp/a.s rts.c")))
+    (system (format "clang -fomit-frame-pointer /tmp/a.s rts.c -o ~a" output))))
diff --git a/tests.scm b/tests.scm
index 39ca240..964b644 100644
--- a/tests.scm
+++ b/tests.scm
@@ -1,3 +1,4 @@
+(load "codegen.scm")
 (load "typecheck.scm")
 
 (define (test actual expected)
@@ -6,5 +7,30 @@
 	   (format "test failed:\nexpected: ~a\nactual:   ~a"
 		   expected actual))))
 
+(define (read-file file)
+  (call-with-input-file file
+    (lambda (p)
+      (let loop ((next (read-char p))
+                 (result ""))
+        (if (eof-object? next)
+            result
+            (loop (read-char p) (string-append result (string next))))))))
+
+(define (test-prog prog output)
+  (compile-to-binary prog "/tmp/test-prog")
+  (system "/tmp/test-prog > /tmp/test-output.txt")
+  (let ((str (read-file "/tmp/test-output.txt")))
+    (test (substring str 0 (- (string-length str) 1))
+	  output)))
+
 (test (typecheck '(lambda (x) (+ ((lambda (y) (x y 3)) 5) 2)))
       '(abs (abs int (abs int int)) int))
+
+(test-prog '(+ 1 2) "3")
+(test-prog '((lambda (x) ((lambda (y) (+ x y)) 42)) 100) "142")
+; todo: support recursive let
+(test-prog '(let ((x (+ 1 32))
+		  (y x))
+	      ((lambda (z) (+ 1 z)) (* y x)))
+	   "1090")
+
diff --git a/typecheck.scm b/typecheck.scm
index 21b874c..55c2fd8 100644
--- a/typecheck.scm
+++ b/typecheck.scm
@@ -57,11 +57,14 @@
 	(list 'lambda (lambda-args prog) (normalize (caddr prog)))))
    ((app? prog)
     (if (null? (cddr prog))
-	(cons (normalize (car prog)) (normalize (cdr prog))) ; (f a)
-	(list (list (normalize (car prog)) (normalize (cadr prog))) (normalize (caddr prog))))) ; (f a b)
+	`(,(normalize (car prog)) ,(normalize (cadr prog))) ; (f a)
+	`(,(list (normalize (car prog)) (normalize (cadr prog)))
+	  ,(normalize (caddr prog))))) ; (f a b)
+	;; (list (list (normalize (car prog))
+	;; 	    (normalize (cadr prog))) (normalize (caddr prog))))) ; (f a b)
    ((let? prog)
     (append (list 'let
-		  (map (lambda (x) (cons (car x) (normalize (cdr x))))
+		  (map (lambda (x) `(,(car x) ,(normalize (cadr x))))
 		       (let-bindings prog)))
 	    (map normalize (let-body prog))))
    (else prog)))
-- 
2.30.2