Add notes on ownership

[scheme.git] / codegen.scm

diff --git a/codegen.scm b/codegen.scm
index 7c1c3a150727c969a991021fd2c3470e221f573e..52c494bb233fb728ff907fa5fed63db57fb05478 100644 (file)
--- a/codegen.scm
+++ b/codegen.scm
@@ -46,9 +46,9 @@
   (codegen-expr a si env)
   (emit "movq %rax, ~a(%rbp)" si)
   (codegen-expr b (- si wordsize) env)
-  (emit "subq ~a(%rbp), %rax" si)
-  (emit "not %rax")
-  (emit "andq $1, %rax"))
+  (emit "## ~a = ~b" a b)
+  (emit "cmpq ~a(%rbp), %rax" si)
+  (emit "sete %al"))
 
                                        ; 'write file handle addr-string num-bytes
 
@@ -249,11 +249,6 @@
     (emit "pop %rbp") ; restore caller's base pointer
     (emit "ret")))
 
-(define (codegen-string label)
-  (case target
-    ('darwin (emit "movq ~a@GOTPCREL(%rip), %rax" label))
-    ('linux  (emit "lea $~a, %rax" label))))
-
 (define cur-label 0)
 (define (fresh-label)
   (set! cur-label (+ 1 cur-label))
@@ -272,6 +267,7 @@
     (emit "~a:" exit-label)))
 
 (define (codegen-expr e si env)
+  (emit "# ~a" e)
   (case (ast-type e)
     ('closure (codegen-closure (cadr e) (caddr e) si env))
     ('app
@@ -300,7 +296,8 @@
     ('bool-literal (emit "movq $~a, %rax" (if e 1 0)))
     ('int-literal (emit "movq $~a, %rax" e))
     
-    ('static-string (codegen-string (cadr e)))
+    ('static-string (emit "movq ~a@GOTPCREL(%rip), %rax"
+                         (cadr e)))
 
     (else (error #f "don't know how to codegen this"))))
 
@@ -487,6 +484,8 @@
     (emit "movq %rax, (%rsi)")))
 
 (define (codegen program)
+  (set! cur-label 0)
+  (set! cur-lambda 0)
   (let* ((extract-res-0 (extract-strings program))
         (strings (car extract-res-0))
         (extract-res-1 (extract-lambdas (cdr extract-res-0)))