From ba682d8f6abdf80ed762ca2d8089039c7a524eb5 Mon Sep 17 00:00:00 2001
From: Felix Martin <mail@felixm.de>
Date: Thu, 15 Apr 2021 12:41:52 -0400
Subject: [PATCH] Start to work on 5.33

---
 ex-5_31-xx.scm        | 60 ++++++++++++++++++++++++++++++++++++++++---
 misc/ch5-compiler.scm |  2 +-
 2 files changed, 58 insertions(+), 4 deletions(-)

diff --git a/ex-5_31-xx.scm b/ex-5_31-xx.scm
index 80c7e4e..06160e4 100644
--- a/ex-5_31-xx.scm
+++ b/ex-5_31-xx.scm
@@ -1,4 +1,5 @@
 (load "util.scm")
+(load "misc/ch5-compiler.scm")
 
 (display "\nex-5.31 - save-and-restore-for-apply\n")
 
@@ -61,10 +62,63 @@ ev-appl-did-operator-no-restore
 ; before runtime
 (display "[answered]\n")
 
-(display "\nex-5.33\n")
 
-(display "CONTINUE at 5.5.3\n")
+(display "\nex-5.33 - compare-factorial-definitions\n")
+
+(define (compile-to-file code target linkage file-name)
+  (define (write-list-to-port xs port)
+    (if (null? xs)
+      '()
+      (begin
+        (display (car xs) port)
+        (display "\n" port)
+        (write-list-to-port (cdr xs) port))))
+  (let* ((compile-result (compile code target linkage))
+         (assembly-insts (statements compile-result))
+         (port (open-output-file file-name)))
+    (write-list-to-port assembly-insts port)
+    (display "[")
+    (display file-name)
+    (display "]\n")
+    (close-output-port port)))
+
+; Uncomment the following lines to write the assembly code for the to methods
+; into files.
+
+;(compile-to-file
+; '(define (factorial n)
+;    (if (= n 1)
+;        1
+;        (* (factorial (- n 1)) n)))
+; 'val 'next "factorial.sicp-asm")
+;
+;; reset label counter to the same labels for diff
+;(define label-counter 0)
+;
+;(compile-to-file
+;  '(define (factorial-alt n)
+;    (if (= n 1)
+;        1
+;        (* n (factorial-alt (- n 1)))))
+; 'val 'next "factorial-alt.sicp-asm")
+
+; $ diff factorial.sicp-asm factorial-alt.sicp-asm
+; 33,36c33,34
+; < (assign val (op lookup-variable-value) (const n) (reg env))
+; < (assign argl (op list) (reg val))
+; < (save argl)
+; ---
+; > (save env)
+; > (assign proc (op lookup-variable-value) (const factorial-alt) (reg env))
+; 63c61,63
+; < (restore argl)
+; ---
+; > (assign argl (op list) (reg val))
+; > (restore env)
+; > (assign val (op lookup-variable-value) (const n) (reg env))
+
 
 (display "\nex-5.34\n")
-;(display "\nex-5.35\n")
+
+(display "\nex-5.35\n")
 
diff --git a/misc/ch5-compiler.scm b/misc/ch5-compiler.scm
index c295770..c27c010 100644
--- a/misc/ch5-compiler.scm
+++ b/misc/ch5-compiler.scm
@@ -12,7 +12,7 @@
 ;;;;Then you can compile Scheme programs as shown in section 5.5.5
 
 ;;**implementation-dependent loading of syntax procedures
-(load "ch5-syntax.scm")			;section 4.1.2 syntax procedures
+(load "misc/ch5-syntax.scm")			;section 4.1.2 syntax procedures
 
 
 ;;;SECTION 5.5.1