From ee2cc40968524e6b5d40f1d85e6b50387c7d3e01 Mon Sep 17 00:00:00 2001
From: Felix Martin <mail@felixm.de>
Date: Mon, 26 Apr 2021 15:57:47 -0400
Subject: [PATCH] Make compile and go work and answer 5.45

---
 ex-5_45-xx.scm                       | 44 ++++++++++++++++++++++++++--
 shared/sicp-load-eceval-compiler.scm | 20 +++++++++++++
 shared/sicp-regsim.scm               |  4 +--
 3 files changed, 64 insertions(+), 4 deletions(-)
 create mode 100644 shared/sicp-load-eceval-compiler.scm

diff --git a/ex-5_45-xx.scm b/ex-5_45-xx.scm
index 1efc026..6ab39b5 100644
--- a/ex-5_45-xx.scm
+++ b/ex-5_45-xx.scm
@@ -1,3 +1,43 @@
-(load "shared/util.scm")
+(load "shared/util")
+(load "shared/sicp-load-eceval-compiler")
+(load "shared/sicp-compiler")
 
-(display "\nex-5.45\n")
+
+(display "\nex-5.45 - factorial-stack-usage-comparison\n")
+
+;(compile-and-go
+; '(begin
+;    (define (factorial n)
+;      (if (= n 1)
+;        1
+;        (* (factorial (- n 1)) n)))
+;    (factorial 10)))
+
+; a.
+
+; | (factorial 10) | pushes | depth  |
+; | -------------- | ------ | ------ |
+; | machine        |     18 |     18 |
+; | compiled       |     56 |     29 |
+; | evaluator      |    310 |     35 |
+
+; | (factorial 20) | pushes | depth  |
+; | -------------- | ------ | ------ |
+; | machine        |     38 |     38 |
+; | compiled       |    116 |     59 |
+; | evaluator      |    630 |     65 |
+
+; pushes(compiled/machine) = 3
+; depth(compiled/machine) = 1.5
+
+; pushes(evaluator/compiled) = 5.5
+; depth(evaluator/compiled) = 1.2
+
+; b. Use special handling for primitive procedures from exercise 5.38.
+
+(display "[answered]\n")
+
+(display "\nex-5.46 - fibo-stack-usage-comparison\n")
+
+
+(display "\nex-5.47\n")
diff --git a/shared/sicp-load-eceval-compiler.scm b/shared/sicp-load-eceval-compiler.scm
new file mode 100644
index 0000000..55ad39b
--- /dev/null
+++ b/shared/sicp-load-eceval-compiler.scm
@@ -0,0 +1,20 @@
+;;;; LOADS THE EXPLICIT-CONTROL EVALUATOR FROM SECTION 5.4 OF
+;;;; STRUCTURE AND INTERPRETATION OF COMPUTER PROGRAMS, WITH
+;;;; ALL THE SUPPORTING CODE IT NEEDS IN ORDER TO RUN.
+
+;;;;This is like load-eceval.scm except that it loads the version
+;;;; of eceval that interfaces with compiled code
+;;;;It doesn't load the compiler itself -- loading the compiler is up to you.
+
+;;;; **NB** The actual "load" calls are implementation dependent.
+
+(load "shared/sicp-regsim")			;reg machine simulator
+
+;; **NB** next file contains another "load"
+(load "shared/sicp-eceval-support")		;simulation of machine operations
+
+;;**NB** eceval-compiler *must* be loaded after eceval-support,
+;;  so that the version of user-print in eceval-compiler will override
+;;  the version in eceval-support
+(load "shared/sicp-eceval-compiler")		;eceval itself
+					;and interface to compiled code
diff --git a/shared/sicp-regsim.scm b/shared/sicp-regsim.scm
index f3322fc..0a75f9d 100644
--- a/shared/sicp-regsim.scm
+++ b/shared/sicp-regsim.scm
@@ -291,7 +291,7 @@
         ((eq? (car inst) 'restore)
          (make-restore inst machine stack pc))
         ((eq? (car inst) 'label)
-         (make-label pc))
+         (make-pseudo-label pc))
         ((eq? (car inst) 'perform)
          (make-perform inst machine labels ops pc))
         ((eq? (car inst) 'inc)
@@ -299,7 +299,7 @@
         (else (error "Unknown instruction type -- ASSEMBLE"
                      inst))))
 
-(define (make-label pc)
+(define (make-pseudo-label pc)
   (lambda () (advance-pc pc)))
 
 (define (make-assign inst machine labels operations pc)